Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Groundwater and surface water management and drinking water issues in the Hatzic Valley Magwood, Simone Barbara 2004

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
831-ubc_2004-0267.pdf [ 16.79MB ]
Metadata
JSON: 831-1.0091590.json
JSON-LD: 831-1.0091590-ld.json
RDF/XML (Pretty): 831-1.0091590-rdf.xml
RDF/JSON: 831-1.0091590-rdf.json
Turtle: 831-1.0091590-turtle.txt
N-Triples: 831-1.0091590-rdf-ntriples.txt
Original Record: 831-1.0091590-source.json
Full Text
831-1.0091590-fulltext.txt
Citation
831-1.0091590.ris

Full Text

Groundwater and Surface Water Management and Drinking Water Issues in the Hatzic Valley by Simone Barbara Magwood B . S c , The University of Waterloo, 2000 A THESIS SUBMITTED IN PARTIAL FULFILMENT O F THE REQUIREMENTS FOR THE DEGREE OF Master of Science in THE F A C U L T Y OF G R A D U A T E STUDIES Institute of Resources, Environment and Sustainability Resource Management and Environmental Studies Program We accept this thesis as conforming to the required siandard T H E UNIVERSITY OF BRITISH COLUMBIA April 2004 © Simone Barbara Magwood 2004 Library Authorization In presenting this thesis in partial fulfillment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. 5\rnftr\e. rfVxaiPoodl April 1 ^ . ^ 0 0 ^ Name of Author (please print) Date (dd/mm/yyyy) Title of Thesis: GrouacluJaW g^d SuC-fac-e \Uakr 1Y\Afmaen\pr^ lOfiYiK-i 'WA VJaW I s s u e r m (ft* Degree: jY\g£ \e( S d g A C ^ Year: ^QoH J Department of Rgsaurcg Inanity mer\r *M <£n yiYan^n-hii Sjudf. The University of British Columbia Vancouver, BC Canada Abstract In rural areas, water is often supplied by private groundwater wells. Individual well owners have little control over the quality of their drinking water which can be impacted by adjacent land use. The objectives of this project were to determine the quality of drinking water in a rural watershed, investigate the links between groundwater, surface water and land use, and compare the results with the residents' perceptions. Field research was conducted in the Hatzic Valley in the Lower Fraser Valley of British Columbia, a rural watershed with mixed land use. With the help of local volunteers, 75 groundwater samples were collected and analysed in July 2002 and March 2003. Stream water samples were collected at 19 stations semi-monthly between May 2002 and May 2003 to determine linkages between 1) land use and surface water and 2) surface water and groundwater quality. A spatial database was created and the percentage of the four predominant land uses were calculated within several radii of the wells sampled. The perceptions and opinions of local residents were collected using a questionnaire and the results compared with the water quality data. Analysis showed that water quality throughout the valley is good; however, two wells exceeded the health standard for nitrate-N and 10 more wells had nitrate-N levels above 3 mg/L (considered indicative of land use impacts). All the wells with elevated N0 3-N were shallow (less than 12 m deep). Percent forest cover surrounding the wells was negatively correlated with nitrate level, while percent urbanised land was positively related to nitrate. The cause of high nitrate in the urban areas is thought to be from septic systems. Surface water quality was also high but showed overall degradation from headwaters to the mouth as agriculture increased in the watershed. The majority of residents perceived their water quality to be good or excellent. The residents base their perceptions on tangible indicators rather than chemically determined ones as those who have negative perceptions of their water tended to have high levels of iron and manganese rather than nitrate. The latter is detectable without chemical analysis while the former is not. Very few filter, treat or test their water quality on a regular basis. Table of contents A B S T R A C T II T A B L E O F C O N T E N T S I l l T A B L E O F T A B L E S ..VI T A B L E O F FIGURES VII A C K N O W L E D G E M E N T S IX A B B R E V I A T I O N S X 1.0 I N T R O D U C T I O N AND C O N T E X T 1 1.1 RESEARCH QUESTIONS: 2 1.2 DRINKING WATER VULNERABILITY IN CANADA AND BRITISH COLUMBIA 2 1.3 MULTIPLE BARRIER APPROACH 3 1.3.1 Drinking Water Sources 4 1.3.1a Surface Water ....4 1.3.1b Groundwater 5 1.3.1c Land Use and Source Protection 6 1.3.2 Water Treatment 7 1.3.3 Distribution System 8 1.3.4 Monitoring 9 1.3.5 Response 10 1.4 NITRATE AND PATHOGENS - CONTAMINANTS OF CONCERN 11 1.4.1 Nitrate U 1.4.2 Coliforms 12 1.4.3 Nitrate: A useful indicator for coliform contamination? 13 1.5 OTHER WATER QUALITY PARAMETERS 14 1.5.1 Iron and Manganese 14 1.5.2 Electrical Conductivity 15 1.5.3 Orthophosphate (P043') 15 1.6 GROUNDWATER IN THE LOWER FRASER VALLEY 16 2.0 R E S E A R C H L O C A T I O N 17 2.1 INTRODUCTION TO HATZIC VALLEY 17 2.2 LAND USE IN THE WATERSHED 18 2.3 DRINKING WATER SOURCES 20 2.4 AQUIFER CLASSIFICATION 20 2.4.1 Nicomen Slough Aquifer 22 2.4.2 Hatzic Prairie Aquifer 24 2.4.3 Miracle Valley Aquifer 26 3.0 M E T H O D O L O G Y 34 3.1 GROUNDWATER SURVEY AND QUESTIONNAIRE 34 3.1.1 Participant Selection 34 3.1.2 Groundwater Survey - Data Collection 35 3.1.3 Chemical Analysis 36 3.1.4 Coliform Analysis 36 iii 3.1.5 Opinion Survey 37 3 . 2 S T R E A M S A M P L I N G 3 7 3 . 3 G I S D A T A B A S E 3 8 3 . 4 S T A T I S T I C A L A N A L Y S I S 4 0 3.4.1 Correlation 41 3.4.2Mann-Whitney UTest 41 3.4.3 Kruskal-Wallis Test 42 3.4.4 Boxplots 42 3.4.5 Cluster Analysis 43 4 . 0 R E S U L T S A N D D I S C U S S I O N 4 4 4 .1 G R O U N D W A T E R Q U A L I T Y 4 4 4.1.1 Parameters exceeding the Guidelines for Canadian Drinking Water Quality 46 4 . 1 . 1 a p H 4 6 4 . 1 . 1 b M e t a l s 4 6 4.1.2 Conductivity 48 4.1.5 Orthophosphate: POA 49 4.1.2 Nitrate-N (N03-N) 51 4.1.4 Coliforms 52 4 . 2 P A R A M E T E R I N T E R A C T I O N S 5 3 4.2.1 Seasonal Variation 53 4.2.2 Parameter Correlation 54 4.2.3 Depth 55 4 . 3 P A R A M E T E R S I N F L U E N C E D B Y G E O L O G Y 5 6 4.4.1 Cluster Analysis 58 4 . 4 G R O U N D W A T E R A N D L A N D U S E I N T E R A C T I O N S 6 1 4 . 6 S U R F A C E W A T E R Q U A L I T Y 6 6 4.6.1 Temperature 68 4.6.2 Nitrate 68 4.6.3 Conductivity...: 69 4 . 7 G R O U N D W A T E R A N D S U R F A C E W A T E R I N T E R A C T I O N S 7 3 4.7.1 Surface Water Impacts on Groundwater Quality 7 7 4 . 8 S U R V E Y R E S U L T S A N D D I S C U S S I O N 7 8 4.8.1 General Responses 78 4 . 8 . l a W a t e r Q u a l i t y P e r c e p t i o n 7 8 4 . 8 . 1 b W a t e r S o u r c e s 7 9 4 . 8 . 1 c T r e a t m e n t 81 4 . 8 . I d M o n i t o r i n g 8 2 4.8.2 Regional Variation in Survey Response 82 4 . 8 . 2 a S e p t i c S y s t e m s 8 4 4.8.3 Other Correlations 85 4 . 8 . 2 a W a t e r Q u a l i t y P e r c e p t i o n a n d C h e m i c a l P a r a m e t e r s 8 6 5 . 0 S U M M A R Y A N D C O N C L U S I O N S 88 5.1 S U M M A R Y 8 8 5.1.1 Differences between Aquifers 88 5.1.2 Nitrate and Depth 89 5.1.3 Nitrate and Land Use 89 5.1.4 Surface Water Conditions 89 5.1.5 Land use impacts on surface water quality 89 5.1.6 Groundwater and Surface Water Interactions 90 iv 5.1.7 Perceptions 90 5.2 R E C O M M E N D A T I O N S 9 1 5.2.1 Hatzic Island 91 5.2.2 Other Impacted Wells 92 5.2.3 Other Factors Influencing Water Quality 92 5.3 C O N C L U S I O N S 9 2 R E F E R E N C E S 94 A P P E N D I X E S 99 A P P E N D I X 1 - I N I T I A L C O N T A C T L E T T E R 9 9 A P P E N D I X 2 - N E W S R E L E A S E 1 0 0 A P P E N D I X 3 - I N S T R U C T I O N L E T T E R 101 A P P E N D I X 4 - R E P O R T B A C K L E T T E R 1 0 2 A P P E N D I X 5 S U R V E Y 1 0 3 A P P E N D I X 6 - R E S U L T S O F B L I N D D U P L I C A T E S 1 0 7 A P P E N D I X 7 . S O I L A N D S U R F I C I A L G E O L O G Y C O D E S 1 0 8 A P P E N D I X 8 - G R O U N D W A T E R S A M P L I N G D A T A 1 0 9 A P P E N D I X 10 . D E N D O G R A M U S E D T O D E T E R M I N E C L U S T E R S I N F I G U R E 2 5 1 2 2 v Table of Tables T a b l e 1. T h e M u l t i - B a r r i e r A p p r o a c h t o W a t e r T r e a t m e n t a n d D e l i v e r y 3 T a b l e 2 . N u m b e r o f w e l l e x c e e d i n g t h e G u i d e l i n e s f o r C a n a d i a n D r i n k i n g W a t e r Q u a l i t y , C a r m i c h e a l et a l . ( 1 9 9 5 ) 1 6 T a b l e 3 . H a t z i c V a l l e y L a n d U s e 18 T a b l e 4 . L a n d U s e A Q 1 2 4 T a b l e 5 . L a n d U s e A Q 2 2 6 T a b l e 6 . L a n d U s e A Q 3 2 9 T a b l e 7 . L a n d u s e C a t e g o r i e s C o d e d i n t o G I S 3 9 T a b l e 8. G r o u n d w a t e r S a m p l i n g R e s u l t s : S u m m a r y S t a t i s t i c s f o r E a c h P a r a m e t e r w i t h a t L e a s t O n e S a m p l e a b o v e t h e D e t e c t i o n L i m i t ( M D C ) b 4 5 T a b l e 9 . N u m b e r o f w e l l s e x c e e d i n g t h e G u i d e l i n e s f o r C a n a d i a n D r i n k i n g W a t e r Q u a l i t y , H a t z i c V a l l e y S a m p l i n g , 2 0 0 2 , 2 0 0 3 4 6 T a b l e 1 0 . C o m p a r i s o n o f m a x i m u m C u , Z n , C a a n d M g l e v e l s i n H a t z i c V a l l e y w i t h r e s u l t s o f M e r a n g e r et a l , 1 9 7 9 4 8 T a b l e 1 1 . H i g h c o n d u c t i v i t y w e l l s 4 8 T a b l e 1 2 . S a m p l e s w i t h N i t r a t e - N v a l u e s a b o v e 3 m g / L i n at l e a s t o n e s a m p l i n g 51 T a b l e 1 3 . N i t r a t e V a l u e s a n d C o l i f o r m 5 3 T a b l e 1 4 . R e s u l t s o f s e a s o n a l a n a l y s i s 5 4 T a b l e 1 5 . C o r r e l a t i o n s b e t w e e n s e l e c t e d p a r a m e t e r s ( S p e a r m a n ' s R a n k c o r r e l a t i o n c o e f f i c i e n t s ) . 5 5 T a b l e 1 6 . S i g n i f i c a n c e t e s t i n g b y a q u i f e r , K r u s k a l - W a l l i s a n d M a n n - W h i t n e y t es t s 5 8 T a b l e 1 7 . S p e a r m a n ' s R a n k C o r r e l a t i o n C o e f f i c i e n t s : L a n d U s e v s N i t r a t e 6 2 T a b l e 1 8 . S p e a r m a n ' s R a n k C o r r e l a t i o n C o e f f i c i e n t s S u r f a c e W a t e r v s . L a n d U s e 6 8 T a b l e 1 9 . R e s p o n s e s t o " W h a t i s y o u r p e r c e p t i o n o f t he w a t e r q u a l i t y f r o m y o u r w e l l ? " 7 8 T a b l e 2 0 . G r o u n d w a t e r I m p a c t o n L o c a l R i v e r s 81 T a b l e 2 1 . F r e q u e n c y o f C h e m i c a l a n d B i o l o g i c a l T e s t i n g 8 2 T a b l e 2 2 . C r o s s - t a b : L o c a t i o n v s . F i l t r a t i o n 8 3 T a b l e 2 3 . C r o s s - T a b : L o c a t i o n v s . d e p t h t o w a t e r t a b l e 8 3 T a b l e 2 4 . C r o s s - t a b : L o c a t i o n v s . a g g r e g a t e e x t r a c t i o n 8 4 T a b l e 2 5 . C r o s s - t a b s : L o c a t i o n v s . I m p o r t a n c e o f S e p t i c S y s t e m s 8 4 T a b l e 2 6 . C r o s s - t a b s : L o c a t i o n v s . S e w e r S y s t e m I n s t a l l a t i o n 8 5 T a b l e 2 7 . C r o s s - T a b : W a t e r Q u a l i t y P e r c e p t i o n v s . F i l t r a t i o n 8 6 T a b l e 2 8 . S p e a r m a n ' s C o r r l e a t i o n : D r i n k i n g W a t e r P e r c e p t i o n 8 7 vi Table of Figures F i g u r e 1. L o c a t i o n o f H a t z i c V a l l e y 17 F i g u r e 2 . L a n d U s e i n t h e H a t z i c V a l l e y '. 19 F i g u r e 3 . W a t e r s h e d a n d A q u i f e r B o u n d a r i e s a n d A r e a s , H a t z i c , B r i t i s h C o l u m b i a 2 1 F i g u r e 4 . A Q 1 - N i c o m e n S l o u g h A q u i f e r 2 3 F i g u r e 5 . A Q 2 - H a t z i c P r a i r i e A q u i f e r 2 5 F i g u r e 6 . A Q 3 - M i r a c l e V a l l e y A q u i f e r 2 7 F i g u r e 7 . L o c a t i o n s o f W e l l L o g P r o f i l e s 3 0 F i g u r e 8. W e l l P r o f i l e 1. S y l v e s t e r R o a d 3 1 F i g u r e 9 . W e l l L o g P r o f i l e 2 . H a r t l e y R o a d 3 2 F i g u r e 1 0 . W e l l L o g P r o f i l e 3 . S t a v e L a k e R o a d 3 3 F i g u r e 1 1 . L o c a t i o n o f W e l l s S a m p l e d 3 4 F i g u r e 1 2 . L o c a t i o n o f S t r e a m S a m p l i n g S t a t i o n s 3 8 F i g u r e 1 3 . L a n d u s e b u f f e r s s u r r o u n d i n g w e l l s i n A Q 1 4 0 F i g u r e 14 . W e l l s e x c e e d i n g t h e C G D W Q f o r F e a n d M n 4 7 F i g u r e 1 5 . B o x p l o t s o f c o n d u c t i v i t y s h o w i n g o u t l i e r s 4 9 F i g u r e 1 6 . B o x p l o t s o f C o n d u c t i v i t y , o u t l i e r s ( w e l l s 2 6 , 7 7 , 4 2 , 4 0 , 2 5 , 4 5 ) r e m o v e d 4 9 F i g u r e 1 7 . B o x p l o t o f P 0 4 g r o u p e d b y a q u i f e r ( a q u i f e r 1 s p l i t i n t o t w o g r o u p s , H a t z i c I s l a n d a n d a r e a e a s t o f H a t z i c i s l a n d ) 5 0 F i g u r e 1 8 . D e p t h B o x p l o t ( D i v i s i o n b y A q u i f e r ) 5 5 F i g u r e 1 9 . N i t r a t e v s . D e p t h ( w i n t e r d a t a ) 5 6 F i g u r e 2 0 . S e a s o n a l C h a n g e i n N i t r a t e v s . D e p t h 5 6 F i g u r e 2 1 . C o n d u c t i v i t y B o x p l o t 5 7 F i g u r e 2 2 . C a l c i u m B o x p l o t 5 7 F i g u r e 2 3 . S i l i c o n B o x p l o t 5 7 F i g u r e 2 4 . O r t h o p h o s p h a t e B o x p l o t 5 7 F i g u r e 2 5 . C l u s t e r s b a s e d o n S i l i c o n a n d C a l c i u m 5 9 F i g u r e 2 6 . S i l i c o n v s . C a l c i u m ( b y a q u i f e r ) 6 0 F i g u r e 2 7 . E C v s . P 0 4 ( b y A q u i f e r ) 6 0 F i g u r e 2 8 . M g v s . S r ( b y a q u i f e r ) 6 1 F i g u r e 2 9 . B o x p l o t - N i t r a t e v s . F o r e s t R a n k s ( w i n t e r a n d s u m m e r ) f o r a 1 0 0 m l a n d u s e b u f f e r . 6 3 F i g u r e 3 0 . B o x p l o t - N i t r a t e v s . U r b a n R a n k s ( w i n t e r a n d s u m m e r ) f o r a 1 0 0 m l a n d u s e b u f f e r . 6 4 F i g u r e 3 1 . H a t z i c V a l l e y M a i n s t e m a n d S e l e c t e d T r i b u t a r i e s 6 7 F i g u r e 3 2 . A v e r a g e D r y a n d W e t S e a s o n T e m p e r a t u r e s - M a i n s t e m 7 0 F i g u r e 3 3 . A v e r a g e D r y a n d W e t S e a s o n T e m p e r a t u r e s - T r i b u t a r y 1 7 0 F i g u r e 3 4 . A v e r a g e D r y a n d W e t S e a s o n T e m p e r a t u r e s - T r i b u t a r y 2 7 0 F i g u r e 3 5 . A v e r a g e D r y a n d W e t S e a s o n T e m p e r a t u r e s - T r i b u t a r y 3 7 0 F i g u r e 3 6 . A v e r a g e W e t a n d D r y S e a s o n N i t r a t e L e v e l s - M a i n s t e m 71 F i g u r e 3 7 . A v e r a g e W e t a n d D r y S e a s o n N i t r a t e L e v e l s - T r i b u t a r y 1 71 F i g u r e 3 8 . A v e r a g e W e t a n d D r y S e a s o n N i t r a t e L e v e l s - T r i b u t a r y 2 71 F i g u r e 3 9 . A v e r a g e W e t a n d D r y S e a s o n N i t r a t e L e v e l s - T r i b u t a r y 3 71 F i g u r e 4 0 . A v e r a g e D r y a n d W e t S e a s o n C o n d u c t i v i t y - M a i n s t e m 7 2 F i g u r e 4 1 . A v e r a g e D r y a n d W e t S e a s o n C o n d u c t i v i t y - T r i b u t a r y 1 7 2 F i g u r e 4 2 . A v e r a g e D r y a n d W e t S e a s o n C o n d u c t i v i t y - T r i b u t a r y 2 7 2 F i g u r e 4 3 . A v e r a g e D r y a n d W e t S e a s o n C o n d u c t i v i t y - T r i b u t a r y 3 7 2 F i g u r e 4 4 . A r e a o f s a m p l i n g n e t w o r k w h e r e s u r f a c e a n d g r o u n d w a t e r i n t e r a c t i o n s a r e m o s t l i k e l y 7 4 F i g u r e 4 5 . C l u s t e r s b a s e d o n s t r e a m t e m p e r a t u r e ( e n t i r e s a m p l i n g p e r i o d ) 7 6 F i g u r e 4 6 . T e m p e r a t u r e C l u s t e r B o x p l o t s 7 7 vii F i g u r e 4 7 . R e s p o n s e s t o t h e q u e s t i o n " H o w i m p o r t a n t a r e t h e f o l l o w i n g a s a g u i d e f o r i n d i c a t i n g t h e q u a l i t y o f y o u r w a t e r ? " 7 9 F i g u r e 4 8 . R e s p o n s e t o t h e q u e s t i o n " H o w i m p o r t a n t a r e t h e s e a c t i v i t i e s i n c a u s i n g w a t e r q u a l i t y p r o b l e m s ? " 8 0 F i g u r e 4 9 . R e s p o n s e s t o t h e q u e s t i o n s " H o w a p p r o p r i a t e d o y o u t h i n k t h e f o l l o w i n g s t r a t e g i e s a r e f o r m a n a g i n g g r o u n d w a t e r r e s o u r c e s " 81 viii Acknowledgements This project could not have been completed without the help of many people, some of whom are acknowledged below. Thank you to my supervisor Hans Schreier and committee, Ken Hall and Roger Beckie. I'd also like to thank Graham Daneluz of the FVRD for mailing lists, airphotos and other invaluable data and contacts. Leigh Lehmann for organizing volunteers and providing the local consultants reports. Bill Walsh for helping collect names and numbers of willing participants. Keren Fergus for not panicking in the face of 80 water samples. Jamie Ross for collecting much of the stream data, great company in the field and bravery in the face of 89 cats. And, Terre Satterfield and Milind Kandlikar for sharing their expertise. Thanks to the residents of the Hatzic Valley for their participation. Big thanks to Mom, Dad and Grandma for always emphasizing the value of education and for the generous "scholarships". And of course Nic, thanks for the encouragement, support and the odd laugh ;-) Finally, this research was inspired by and dedicated to the town of Walkerton and the people who live there. It was great place to grow up - those of us who lived there know it's so much more than just "Ecolf'. Those who fail to learn from the past are doomed to repeat it... let's hope we've all learned a little bit. ix Abbreviations A N O V A - Analysis of Variance AQ1 - Aquifer 1. Nicomen Slough Aquifer AQ2 - Aquifer 2. Hatzic Prairie Aquifer AQ3 - Aquifer 3. Miracle Valley Aquifer B C - British Columbia B C C D C - British Columbia Centre for Disease Control C A D - Computer Assisted Design C F U - Colony Forming Unit E C - Electrical Conductivity FVRD - Fraser Valley Regional District G C D W Q - Guidelines for Canadian Drinking Water Quality GIS - Geographical Information System L F V - Lower Fraser Valley M A C - Maximum Allowable Concentration MDC - Minimum Detection Concentration NPS - Non Point Source P H C L - Pacific Hydrology Consultants Ltd. UK - United Kingdom x 1.0 Introduction and Context "Millions have lived without love, No one has lived without water" T u r k i s h B u s i n e s s m a n ( D e V i l l i e r s , 1 9 9 9 ) "Unlike other important commodities such as oil, copper, or wheat, fresh water has no substitutes for most of its uses" ( P o s t e l et al, 1 9 9 6 ) . T h e i m p o r t a n c e o f w a t e r f o r h u m a n s u r v i v a l c a n n o t b e d i s p u t e d . A h u m a n b e i n g c a n l i v e f o r 4 0 d a y s w i t h o u t f o o d b u t o n l y f i v e d a y s w i t h o u t w a t e r . W e d e p e n d o n c l e a n w a t e r n o t o n l y f o r b a s i c s u r v i v a l b u t a l s o u s e i t i n v i r t u a l l y e v e r y h u m a n e n d e a v o u r . It i s u s e d f o r d r i n k i n g , w a s h i n g , c o o k i n g a n d c l e a n i n g , i n i n d u s t r i a l p r o c e s s e s , t o i r r i g a t e o u r f a r m s a n d t o g e n e r a t e e l e c t r i c i t y . A l t h o u g h w a t e r i s v i t a l f o r h u m a n s u r v i v a l i t i s o n e o f o u r m o s t a b u s e d r e s o u r c e s ( B r a n d l i n g -B e n n e t t , 1 9 9 8 ) . M a n y o f t h e a b o v e a c t i v i t i e s a r e n o t c o n s u m p t i v e , m e a n i n g t h a t s o m e o r a l l o f t h e w a t e r r e t u r n s to t h e e n v i r o n m e n t a f t e r i t i s u s e d ; h o w e v e r , i n m o s t c a s e s t h e w a t e r t ha t i s d i s c h a r g e d b e a r s l i t t l e r e s e m b l a n c e t o t h e w a t e r t ha t w a s i n i t i a l l y w i t h d r a w n . F o r e x a m p l e , h u m a n h a b i t a t i o n s d i s c h a r g e w a t e r t ha t i s c o n t a m i n a t e d w i t h h u m a n w a s t e . M a n y i n d u s t r i e s r e l e a s e w a t e r l a d e n w i t h c h e m i c a l s , a n d w h e n l e a v i n g a f a r m field, w a t e r t h a t h a s b e e n u s e d f o r i r r i g a t i o n o f t e n h a s a h i g h l e v e l o f n u t r i e n t s a n d p e s t i c i d e s . I n a l m o s t e v e r y c a s e w a t e r t ha t i s u s e d b y h u m a n s o r p a s s e s t h r o u g h a r e a s o f h u m a n i n f l u e n c e i s d e g r a d e d i n s o m e w a y . S i n c e w a t e r q u a l i t y i s b e i n g d e g r a d e d a l l o v e r t h e p l a n e t i t i s c h a l l e n g i n g t o f i n d w a t e r t ha t i s s a f e f o r d r i n k i n g . M a n y o f t h e i m p a c t s o n w a t e r q u a l i t y a r e c a u s e d b y n o n - p o i n t s o u r c e p o l l u t i o n a n d a r e c u m u l a t i v e i n n a t u r e ~ t h e u n c e r t a i n t y s u r r o u n d i n g t h e c a u s e s a n d s o u r c e s o f p o t e n t i a l w a t e r q u a l i t y d e g r a d a t i o n m a k e s t h e d e l i v e r y o f s a f e d r i n k i n g w a t e r a c o m p l e x p r o b l e m ( L i c h t e n b e r g a n d P e n n , 2 0 0 3 ) . D i f f e r e n t a r e a s f a c e d i f f e r e n t c h a l l e n g e s i n p r o v i d i n g s a f e d r i n k i n g w a t e r . T h i s p r o j e c t i s a n e x a m i n a t i o n o f t h e c h a l l e n g e s f a c i n g a g r o u p o f r u r a l C a n a d i a n s i n p r o v i d i n g t h e m s e l v e s w i t h s a f e d r i n k i n g w a t e r . T h e f o c u s o f t h e p r o j e c t i s o n t h e i n t e r a c t i o n s b e t w e e n r u r a l d r i n k i n g w a t e r q u a l i t y , l a n d u s e a n d i n d i v i d u a l p e r c e p t i o n s o f w a t e r q u a l i t y . F i e l d w o r k w a s d o n e i n a w a t e r s h e d i n B r i t i s h C o l u m b i a ' s L o w e r F r a s e r V a l l e y . U s i n g t h i s w a t e r s h e d as a f o c u s , t h e p r o j e c t w i l l a t t e m p t t o p r o v i d e a c o m p r e h e n s i v e d i s c u s s i o n o f t h e p r o b l e m s f a c i n g , a n d o p t i o n s a v a i l a b l e t o , r u r a l r e s i d e n t s w h o w i s h t o p r o t e c t t h e i r h e a l t h a n d p r o v i d e t h e m s e l v e s w i t h a s a f e s o u r c e o f w a t e r t o d r i n k . 1 1.1 Research Questions: T h e p u r p o s e o f t h i s p r o j e c t i s t o a n s w e r t h e f o l l o w i n g q u e s t i o n s : 1. W h a t i s t h e s u r f a c e a n d g r o u n d w a t e r q u a l i t y i n t he H a t z i c W a t e r s h e d ? 2 . C a n g e o l o g i c a l e f f e c t s o n w a t e r q u a l i t y b e s e p a r a t e d f r o m l a n d u s e e f f e c t s ? 3 . Is t h e r e a q u a n t i f i a b l e l i n k b e t w e e n g r o u n d w a t e r q u a l i t y a n d l a n d u s e ? 4 . Is t h e r e a q u a n t i f i a b l e l i n k b e t w e e n s u r f a c e w a t e r q u a l i t y a n d l a n d u s e ? 5 . W h e r e a r e t h e r e l i n k s b e t w e e n g r o u n d w a t e r q u a l i t y a n d s u r f a c e w a t e r q u a l i t y ? 1.2 Drinking Water Vulnerability in Canada and British Columbia D r i n k i n g w a t e r i n C a n a d a i s r e l a t i v e l y s a f e . I n m a n y c o u n t r i e s i t i s r o u t i n e f o r p e o p l e t o d i e f r o m d r i n k i n g c o n t a m i n a t e d w a t e r . I n C a n a d a , h o w e v e r , i t i s a n a t i o n a l t r a g e d y a n d p e o p l e a r e s h o c k e d a n d a p p a l l e d i f p e o p l e d i e f r o m d r i n k i n g w a t e r . O n e s u c h t r a g e d y o c c u r r e d i n O n t a r i o i n 2 0 0 0 . I n M a y o f t ha t y e a r , a w a t e r b o r n e o u t b r e a k of Escherichia coli 0 1 5 7 : H 7 a n d Campylobacter jejuni i n t h e t o w n o f W a l k e r t o n r e s u l t e d i n s e v e n d e a t h s a n d m a d e 2 3 0 0 c i t i z e n s i l l ( O ' C o n n o r , 2 0 0 2 a ) . T h e W a l k e r t o n t r a g e d y s e r v e d as a c a t a l y s t f o r j u r i s d i c t i o n s a c r o s s C a n a d a t o e x a m i n e h o w d r i n k i n g w a t e r i s r e g u l a t e d a n d d e l i v e r e d t o t h e c o m m u n i t i e s w h o c o n s u m e i t . T h i s o u t b r e a k r e c e i v e d a l o t o f a t t e n t i o n b e c a u s e p e o p l e d i e d , h o w e v e r , i t w a s n o t t h e f i r s t ( n o r t h e l a s t ) o u t b r e a k o f w a t e r b o r n e d i s e a s e t o t a k e p l a c e i n C a n a d a . B r i t i s h C o l u m b i a ( B C ) a l o n e h a s e x p e r i e n c e d 2 9 w a t e r b o r n e d i s e a s e o u t b r e a k s s i n c e 1 9 8 0 a n d c o n s i s t e n t l y h a s t h e h i g h e s t r a t e o f e n t e r i c d i s e a s e o f a n y p r o v i n c e i n C a n a d a ( P r o v i n c i a l H e a l t h O f f i c e r , 2 0 0 1 ) . A r e p o r t b y B C ' s a u d i t o r g e n e r a l e n t i t l e d " P r o t e c t i n g D r i n k i n g W a t e r S o u r c e s " p u b l i s h e d i n 1 9 9 9 r e c o g n i z e d t he p o t e n t i a l f o r r u r a l ( a n d u r b a n ) d r i n k i n g w a t e r q u a l i t y p r o b l e m s . T h e a u d i t o r f o u n d t ha t t h e r e i s i n a d e q u a t e p r o t e c t i o n o f d r i n k i n g w a t e r s o u r c e s i n B r i t i s h C o l u m b i a a n d t ha t s o u r c e s f o r i n d i v i d u a l a n d s m a l l w a t e r s y s t e m s a r e e s p e c i a l l y v u l n e r a b l e t o t h e e f f e c t s o f s u r r o u n d i n g l a n d u s e s . S o o n a f t e r , B . C . ' s P r o v i n c i a l H e a l t h O f f i c e r ( 2 0 0 1 ) i s s u e d a r e p o r t h i g h l i g h t i n g t h e p u b l i c h e a l t h p e r s p e c t i v e o n d r i n k i n g w a t e r q u a l i t y i n B . C . T h i s r e p o r t a l s o s p e c i f i e d c o n c e r n s a b o u t r u r a l d r i n k i n g w a t e r a n d h i g h l i g h t e d t h e m a n y k n o w l e d g e g a p s a b o u t r u r a l s y s t e m s . T h e f i n d i n g s o f b o t h r e p o r t s w e r e t h e n e c h o e d b y t h e P a n e l R e v i e w o n B r i t i s h C o l u m b i a ' s D r i n k i n g W a t e r P r o t e c t i o n A c t ( 2 0 0 2 ) w h i c h r e c o m m e n d e d t h a t a n e w D r i n k i n g W a t e r P r o t e c t i o n A c t " s t r e n g t h e n s o u r c e p r o t e c t i o n m e a s u r e s " as w e l l a s " p r o v i d e s u p p o r t t o s m a l l s y s t e m s " . T h e a b o v e r e p o r t s h a v e h i g h l i g h t e d t he n e e d f o r m o r e i n f o r m a t i o n t o b e g a t h e r e d a b o u t r u r a l w a t e r s y s t e m s i n B r i t i s h C o l u m b i a . A m o n g t h e e x a m p l e s o f " w h a t w e d o n ' t k n o w " l i s t e d i n t h e 2 P r o v i n c i a l H e a l t h O f f i c e r ' s r e p o r t w e r e q u e s t i o n s s u c h as " H o w m a n y w a t e r s y s t e m a r e t h e r e i n B . C . t o d a y . . . w h a t i s t h e w a t e r s o u r c e . . . a n d t h e p o p u l a t i o n s e r v e d b y e a c h s y s t e m . . . w h a t a r e t h e p o t e n t i a l s o u r c e s o f c o n t a m i n a t i o n . . . h o w i s t he s y s t e m m a i n t a i n e d . . . " ( P r o v i n c i a l H e a l t h O f f i c e r , 2001). T h e r e i s c u r r e n t l y n o c e n t r a l i z e d d a t a m a n a g e m e n t s y s t e m t o r e c o r d t h i s i n f o r m a t i o n . 1.3 Multiple Barrier Approach S i n c e t h e W a l k e r t o n E.coli c o n t a m i n a t i o n i n M a y 2000 m u c h a t t e n t i o n h a s b e e n p a i d t o t h e c o n c e p t o f u s i n g m u l t i p l e b a r r i e r s f o r p r o t e c t i o n o f d r i n k i n g w a t e r s u p p l i e s ( P r o v i n c i a l H e a l t h O f f i c e r , 2001; K i r m e y e r et al, 2001; O ' C o n n o r , 2002a, 2002b). B u i l t i n r e d u n d a n c y e n s u r e s t ha t i f o n e b a r r i e r f a i l s t h e r e i s a n o t h e r i n p l a c e t o p r e v e n t c o n t a m i n a t i o n . I n h i s r e p o r t t o t h e W a l k e r t o n I n q u i r y J u s t i c e O ' C o n n o r o u t l i n e s t h e m u l t i - b a r r i e r a p p r o a c h t o w a t e r t r e a t m e n t a n d d e l i v e r y a f r a m e w o r k t ha t r e c o g n i z e s tha t d e l i v e r y o f s a f e d r i n k i n g w a t e r m u s t b e a n i n t e g r a t e d e f f o r t . T h i s f r a m e w o r k , o u t l i n e d i n T a b l e 1, r e m i n d s u s t ha t t r e a t i n g w a t e r b e f o r e d e l i v e r y t o c o n s u m e r s m i g h t n o t b e e n o u g h t o e n s u r e t h e i r s a f e t y . A t t e n t i o n m u s t a l s o b e p a i d t o t h e s o u r c e o f t h e w a t e r , i n c l u d i n g a n y w a t e r s h e d p r o c e s s e s t ha t m i g h t l e a d t o d e g r a d i n g w a t e r q u a l i t y , a s w e l l a s t o w h a t h a p p e n s t o t h e w a t e r i n t h e d i s t r i b u t i o n s y s t e m a f t e r t r e a t m e n t . T h e f i n a l a s p e c t o f t h e m u l t i - b a r r i e r a p p r o a c h i s t h e r e c o g n i t i o n t ha t s o m e t h i n g c o u l d g o w r o n g a t a l l s t a g e s a n d t h e r e f o r e a d e q u a t e m o n i t o r i n g s h o u l d b e i n p l a c e t o d e t e c t p r o b l e m s , a s w e l l as a s y s t e m o f r e s p o n s e s h o u l d b e i n p l a c e i f a l l b a r r i e r s f a i l ( O ' C o n n o r , 2002a). The process of supplying drinking water raises serious public health concerns. A properly structured system for ensuring the safety of drinking water should have multiple barriers: if one protective measure fails, there must be another to back it up. The experts that testified at the inquiry repeatedly emphasized the need for multiple barriers - that is for a robust system with built-in safeguards (O'Connor, 2002a). Table 1. The Multi-Barrier Approach to Water Treatment and Delivery Source of the Water Protection of source water quality by limiting or prohibiting wastewater discharges and other sources of water pollution Water Treatment Adequate treatment such as disinfection and/or filtration Distribution System Safeguarding water quality during storage and distribution Monitoring of Water Quality Monitoring of the distribution system and enforcement of standards. Response to Adverse Test Results If all of the barriers fail, what steps will be taken to protect the public? D r i n k i n g w a t e r s y s t e m s e x i s t i n m a n y d i f f e r e n t f o r m s . I n C a n a d a , c i t i e s a n d t o w n s g e n e r a l l y h a v e c e n t r a l i z e d w a t e r d i s t r i b u t i o n s y s t e m s r u n b y t h e m u n i c i p a l i t y o r s o m e o t h e r f o r m o f p u b l i c o r p r i v a t e u t i l i t y c o m m i s s i o n . R u r a l r e s i d e n t s , o n t h e o t h e r h a n d , o f t e n h a v e p r i v a t e w e l l s o r 3 s u r f a c e w a t e r i n t a k e s s e r v i n g i n d i v i d u a l h o m e s a n d b e a r t h e s o l e r e s p o n s i b i l i t y f o r i n s t a l l a t i o n a n d u p k e e p o f t h e s e s y s t e m s . T h e i m p o r t a n c e o f u s i n g m u l t i p l e b a r r i e r s f o r p r o t e c t i o n o f d r i n k i n g w a t e r s u p p l i e s h a s b e e n s t r e s s e d i n t h e l i t e r a t u r e s i n c e t he W a l k e r t o n t r a g e d y ( O ' C o n n o r , 2 0 0 2 a , 2 0 0 2 b ) , a n d s i n c e M a y 2 0 0 0 l e g i s l a t o r s i n O n t a r i o h a v e b e e n w o r k i n g t o e x p l i c i t l y i n c l u d e t h e s e b a r r i e r s i n l e g i s l a t i o n ( G o v e r n m e n t o f O n t a r i o , 2 0 0 3 ) w h i l e d r i n k i n g w a t e r p r o t e c t i o n l e g i s l a t i o n i n o t h e r j u r i s d i c t i o n s o f t e n i n c l u d e s o n e o r m o r e o f t he b a r r i e r s . I n d i v i d u a l w a t e r s y s t e m s a r e e x e m p t f r o m m o s t d r i n k i n g w a t e r l e g i s l a t i o n m e a n i n g t ha t t h e r e i s n o l e g a l r e q u i r e m e n t f o r r u r a l h o m e o w n e r s t o a p p l y a n y p r o t e c t i v e b a r r i e r s t o t h e i r w a t e r s u p p l i e s . It i s d a n g e r o u s , h o w e v e r , t o t h i n k t ha t i n d i v i d u a l w e l l o w n e r s d o n o t n e e d t o t h i n k a b o u t t h e s e b a r r i e r s s i m p l y b e c a u s e t h e r e i s n o l e g i s l a t i o n r e q u i r i n g t h e m t o d o s o . T h e f o l l o w i n g s e c t i o n s g i v e a n i n d e p t h i n t r o d u c t i o n t o t h e d r i n k i n g w a t e r b a r r i e r s i n c l u d i n g a n o v e r v i e w o f h o w t h e b a r r i e r s f a i l e d i n W a l k e r t o n , h o w t h e y c a n b e a p p l i e d t o m u n i c i p a l s y s t e m s as w e l l a s p o s s i b i l i t i e s f o r a p p l i c a t i o n t o i n d i v i d u a l p r i v a t e w e l l s . 1.3.1 Drinking Water Sources T h e f u n d a m e n t a l c h a r a c t e r i s t i c s o f w a t e r a r e d e t e r m i n e d b y t h e i r s o u r c e . P a r a m e t e r s s u c h as h a r d n e s s a n d i n m a n y c a s e s o d o u r a n d c o l o u r a r e o f t e n d e t e r m i n e d b y t h e p a r e n t m a t e r i a l t h r o u g h o r o v e r w h i c h w a t e r f l o w s . L a n d u s e c a n a l s o a f f e c t w a t e r q u a l i t y t o a l a r g e d e g r e e ( Z e b a r t h et al., 1 9 9 8 ) . T h e t y p e s o f c o n t a m i n a t i o n a s p e c i f i c w a t e r s o u r c e m a y b e a t r i s k f r o m w i l l b e d i f f e r e n t i f t h e s o u r c e i s i n a n u r b a n o r a g r i c u l t u r a l a r e a . W a l k e r t o n ' s c o n t a m i n a t e d g r o u n d w a t e r w a s l i n k e d t o r u n o f f f r o m a n e a r b y f a r m , w h i c h e n t e r e d t h e t o w n ' s a q u i f e r a n d s u b s e q u e n t l y t h e i r w e l l a f t e r a p a r t i c u l a r l y i n t e n s e s t o r m e v e n t . 1.3.1a Surface Water W a t e r f o r h u m a n c o n s u m p t i o n c a n c o m e f r o m e i t h e r s u r f a c e w a t e r o r g r o u n d w a t e r . S u r f a c e w a t e r c a n b e e x t r a c t e d f r o m o n e l a r g e s o u r c e s u c h a s L a k e O n t a r i o , ( w h e r e T o r o n t o d r a w s t h e i r w a t e r ) o r f r o m a c o m b i n a t i o n o f s m a l l e r s o u r c e s s u c h a s t h e r e s e r v o i r s u s e d t o s u p p l y c i t i e s s u c h as S t . J o h n ' s , N e w f o u n d l a n d o r V a n c o u v e r , B C . I n r u r a l a r e a s s m a l l s t r e a m s m a y b e u s e d t o d i r e c t l y s u p p l y i n d i v i d u a l h o m e s w i t h t h e w a t e r t h e y n e e d . I n s o m e c a s e s a l l h u m a n a c t i v i t y i s p r o h i b i t e d w i t h i n t h e w a t e r s h e d s u s e d t o s u p p l y d r i n k i n g w a t e r (as i n t h e c a s e o f V a n c o u v e r ) b u t i n m a n y o t h e r c a s e s m u n i c i p a l i t i e s h a v e n o c o n t r o l o v e r w h a t h a p p e n s t o t h e r i v e r s a n d l a k e s f r o m w h i c h t h e y d r a w t h e i r d r i n k i n g w a t e r . I n d i v i d u a l s w i t h p r i v a t e w a t e r s y s t e m s h a v e e v e n l e s s c o n t r o l . S u r f a c e w a t e r h a s l o n g b e e n r e c o g n i z e d as b e i n g s u s c e p t i b l e t o c o n t a m i n a t i o n b y p a t h o g e n s a n d h a r m f u l c h e m i c a l s ( H a r m a n et al, 2 0 0 0 ) . 4 1.3.1b Groundwater I f a s u i t a b l e s o u r c e o f s u r f a c e w a t e r c a n n o t b e f o u n d , m u n i c i p a l i t i e s o r i n d i v i d u a l s m a y u s e g r o u n d w a t e r t o m e e t t h e i r w a t e r n e e d s . G r o u n d w a t e r i s u s e d b y 2 6 % o f C a n a d i a n s a s t h e i r d r i n k i n g w a t e r s o u r c e . A p p r o x i m a t e l y t w o t h i r d s , o r f i v e m i l l i o n , o f t h e s e u s e r s l i v e i n r u r a l a r e a s ( E n v i r o n m e n t C a n a d a , 2 0 0 3 ) . G r o u n d w a t e r i s a n a t t r a c t i v e o p t i o n f o r r u r a l h o m e o w n e r s b e c a u s e i f i s o f t e n o f h i g h q u a l i t y a n d m o r e b r o a d l y d i s t r i b u t e d t h a n s u r f a c e w a t e r s u p p l i e s ( S u m m e r s a n d F i t z G i b b o n , 2 0 0 3 ) . I n m o s t c a s e s g r o u n d w a t e r h a s t r a d i t i o n a l l y b e e n c o n s i d e r e d l e s s p r o n e t o c o n t a m i n a t i o n t h a n s u r f a c e w a t e r ( R u d o l p h , 1 9 9 8 ) ; h o w e v e r t h e e v e n t s i n W a l k e r t o n s h o w e d t ha t t h i s r e s o u r c e i s n o t f a i l s a f e . G r o u n d w a t e r i s f o u n d i n t h e s p a c e s b e t w e e n p a r t i c l e s o f r o c k a n d s o i l , o r i n c r e v i c e s a n d c r a c k s i n r o c k a n d s o m e t i m e s ( b u t v e r y r a r e l y ) i n c a v e r n s a n d u n d e r g r o u n d r i v e r s . It i s s t o r e d i n w a t e r -b e a r i n g f o r m a t i o n s c a l l e d a q u i f e r s o f w h i c h t h e r e a r e t w o t y p e s , c o n f i n e d a n d u n c o n f i n e d . C o n f i n e d a q u i f e r s a r e p r o t e c t e d f r o m c o n t a m i n a t i o n b y a n i m p e r v i o u s l a y e r o f m a t e r i a l ( s u c h a s c l a y ) b e t w e e n t h e a q u i f e r a n d s u r f a c e . T h i s i m p e r v i o u s l a y e r i s c a l l e d a n a q u i t a r d . T h e s e a q u i f e r s a r e m o r e s e c u r e t h a n u n c o n f i n e d a q u i f e r s ( a l s o s o m e t i m e s c a l l e d s h a l l o w a q u i f e r s ) , w h i c h l a c k a p r o t e c t i v e l a y e r a n d a r e t h e r e f o r e m o r e l i k e l y t o c o m e i n t o c o n t a c t w i t h w a t e r f r o m t h e s u r f a c e . C o n f i n e d a q u i f e r s a r e n o t a l w a y s c o m p l e t e l y p r o t e c t e d a n d m a y s t i l l b e a t r i s k d e p e n d i n g o n t h e g e o l o g y o f t h e a r e a . F o r e x a m p l e , a r e a s o f f r a c t u r e d r o c k ( k a r s t t o p o g r a p h y ) c a n p r o v i d e r a p i d c o n d u i t s f o r s u r f a c e c o n t a m i n a t i o n o f g r o u n d w a t e r . T h e s u b s t r a t e t h r o u g h w h i c h g r o u n d w a t e r m o v e s a c t s as a n a t u r a l f i l t e r f o r m a n y c o n t a m i n a n t s a n d p a t h o g e n i c m i c r o o r g a n i s m s . T h e c a p a c i t y o f t h e g r o u n d t o a c t a s a f i l t e r f o r w a t e r i s a f u n c t i o n o f s e v e r a l f a c t o r s i n c l u d i n g c h a r a c t e r i s t i c s o f t h e s o i l a n d u n d e r l y i n g b e d r o c k a n d t h e n a t u r e a n d c o n c e n t r a t i o n o f p o t e n t i a l p o l l u t a n t s e n t e r i n g t h e s y s t e m . U n f o r t u n a t e l y , t h e s e n a t u r a l p r o c e s s e s h a v e l i m i t s w h i c h c a n b e s t r e s s e d t o t h e p o i n t t ha t t h e y c e a s e t o f u n c t i o n l e a d i n g t o g r o u n d w a t e r c o n t a m i n a t i o n ( S u m m e r s a n d F i t z G i b b o n , 2 0 0 3 ; J a f f e a n d D i N o v o , 1 9 9 7 ) . I n B r i t i s h C o l u m b i a , t h e p e r c e n t a g e o f t h e p o p u l a t i o n w h i c h r e l i e s o n g r o u n d w a t e r i s b e l o w t h e n a t i o n a l a v e r a g e ; o n l y 4 0 % o f r u r a l w a t e r s u p p l i e s a r e p r o v i d e d b y w e l l s ( D a k i n , 1 9 9 4 ) ; h o w e v e r , t h e r e a r e r u r a l a r e a s o f t h e p r o v i n c e tha t r e l y h e a v i l y o n g r o u n d w a t e r t o s u p p l y t h e i r d r i n k i n g w a t e r . T h e L o w e r F r a s e r V a l l e y i s o n e o f t h e s e a r e a s a n d p r e v i o u s s t u d i e s h a v e s h o w n h i g h l e v e l s o f n i t r a t e i n s o m e a q u i f e r s i n t h e v a l l e y . I n a d e t a i l e d g r o u n d w a t e r s t u d y c o m p l e t e d o n t h e 5 H o p i n g t o n A q u i f e r ( n e a r L a n g l e y , B . C . ) , 3 0 - 4 0 % o f s a m p l e s t a k e n w e r e f o u n d t o b e i m p a c t e d b y p o l l u t i o n ( 3 - 1 3 % o f a l l s a m p l e s s h o w e d n i t r a t e v a l u e s a b o v e d r i n k i n g w a t e r h e a l t h s t a n d a r d s ) ( S c h r e i e r et al, 1 9 9 6 ) . I n t h e n e a r b y A b b o s t f o r d A q u i f e r , n e a r l y 6 0 % o f s a m p l e s w e r e f o u n d t o h a v e n i t r a t e - N c o n c e n t r a t i o n s t ha t e x c e e d e d h e a l t h s t a n d a r d s ( L i e b s c h e r et al., 1 9 9 2 ) . B r i t i s h C o l u m b i a i s t h e o n l y p r o v i n c e i n C a n a d a l a c k i n g g r o u n d w a t e r l e g i s l a t i o n . T h e r e a r e n o l i c e n s i n g r e q u i r e m e n t s f o r g r o u n d w a t e r e x t r a c t i o n n o r d o w e l l d r i l l e r s n e e d t o b e l i c e n s e d . T h i s m a k e s g a t h e r i n g o f i n f o r m a t i o n a b o u t g r o u n d w a t e r u s e d i f f i c u l t , as t h e o n l y s o u r c e o f i n f o r m a t i o n i s a v o l u n t a r y r e g i s t r y m a i n t a i n e d b y t h e m i n i s t r y o f w a t e r , l a n d a n d a i r p r o t e c t i o n . A s t h i s r e g i s t r y i s v o l u n t a r y t h e q u a l i t y a n d c o m p l e t e n e s s o f t h e i n f o r m a t i o n i t c o n t a i n s i s v a r i a b l e . 1.3.1c Land Use and Source Protection P r o t e c t i o n o f w a t e r s o u r c e s i s t h e f i r s t s t e p t o w a r d s m a i n t a i n i n g w a t e r t h a t i s s a f e t o d r i n k . I n m o s t a r e a s , l o c a l l a n d u s e a c t i v i t i e s c a n g r e a t l y i n f l u e n c e w a t e r q u a l i t y ( Y a n g g e n a n d B o r n , 1 9 9 0 ) . S u r f a c e a n d g r o u n d w a t e r u s e d f o r d r i n k i n g i s v u l n e r a b l e t o p o l l u t i o n f r o m b o t h p o i n t a n d n o n - p o i n t s o u r c e s . I n t h e r e c e n t p a s t , m u c h a t t e n t i o n h a s b e e n p a i d t o p o l l u t i o n f r o m l a r g e i d e n t i f i a b l e p o i n t s o u r c e s . M a n y a n t i - p o l l u t i o n c a m p a i g n s h a v e s u c c e s s f u l l y f o c u s e d o n o p e r a t i o n s s u c h a s m i n e s , p u l p m i l l s a n d s e w a g e t r e a t m e n t p l a n t s t o t h e e x t e n t t ha t t h e p o l l u t i o n f r o m s u c h i n d u s t r i e s i s h i g h l y m a n a g e d a n d r e g u l a t e d i n N o r t h A m e r i c a . " P o i n t s o u r c e s o f p o l l u t i o n [ i n t h e U n i t e d S t a t e s ] w e r e r e g u l a t e d t h r o u g h f e d e r a l l e g i s l a t i o n . . . i n 1 9 7 2 . A s a c o n s e q u e n c e , 6 0 - 8 0 % o f t h e p o l l u t i o n tha t n o w o c c u r s i n U n i t e d S t a t e s w a t e r s c o m e s f r o m n o n -p o i n t s o u r c e s " ( G i l l i a m et al., 1 9 9 7 ) . I n C a n a d a t h e m a j o r i t y o f c o n t a m i n a t i o n i n r u r a l a r e a s i s f r o m n o n - p o i n t s o u r c e s o f p o l l u t i o n ( B e r k a et al., 2 0 0 1 a n d W e m i c k et al, 1 9 9 8 ) . T h i s t y p e o f p o l l u t i o n i s d i f f i c u l t t o i d e n t i f y , t r a c e a n d t o m i t i g a t e b e c a u s e i t i s c a u s e d b y m u l t i p l e u s e s w i t h i n a s i n g l e w a t e r s h e d . O f t e n i n d i v i d u a l a c t i o n s o r p r o c e s s e s a r e n o t o f a l a r g e e n o u g h m a g n i t u d e t o d e g r a d e w a t e r q u a l i t y ; h o w e v e r , t h e c o m b i n a t i o n o f t h e s e a c t i o n s c a n l e a d t o w a t e r t ha t i s s e r i o u s l y c o n t a m i n a t e d a n d u n f i t f o r h u m a n c o n s u m p t i o n . C o n s i d e r m o d e r n a g r i c u l t u r e , w h i c h d e p e n d s o n a v a s t a r r a y o f c h e m i c a l i n p u t s t o m a i n t a i n t h e h i g h p r o d u c t i v i t y n e e d e d t o f e e d t h e g r o w i n g p o p u l a t i o n o f t h e w o r l d ; t h e c o n s e q u e n c e s o f t h e s e i n p u t s o f t e n r e s u l t i n c u m u l a t i v e d e g r a d a t i o n o f w a t e r q u a l i t y , w h i c h n e g a t i v e l y a f f e c t s w i l d l i f e a n d h u m a n s a l i k e . M o s t o f t h e i n p u t s t o a g r i c u l t u r a l f i e l d s ( e x c e p t p e s t i c i d e s ) a r e n o t i n h e r e n t l y t o x i c . T h e n u t r i e n t s f o u n d i n f e r t i l i z e r s s u c h as n i t r o g e n ( N ) a n d p h o s p h o r u s ( P ) a r e e s s e n t i a l f o r p l a n t g r o w t h a n d d e v e l o p m e n t a n d p l a n t s w o u l d d i e w i t h o u t 6 t h e m . H o w e v e r , w h e n t h e y a r e a p p l i e d i n e x c e s s o f p l a n t c a p a c i t y a n d d r a i n e d q u i c k l y f r o m f i e l d s , t h e y e n t e r w a t e r i n f o r m s t h a t a r e t o x i c t o h u m a n s ( N h r a t e - N ) o r d e t r i m e n t a l t o a q u a t i c l i f e ( s e d i m e n t b o u n d P ) . O t h e r l a n d u s e s t ha t c o n t r i b u t e t o n o n - p o i n t s o u r c e ( N P S ) p o l l u t i o n i n c l u d e f o r e s t r y a c t i v i t y ( i n c l u d i n g l o g g i n g , r o a d b u i l d i n g a n d c h e m i c a l a p p l i c a t i o n ) , u r b a n a n d s u b d i v i s i o n d e v e l o p m e n t , s e p t i c s y s t e m s , r o a d t r a n s p o r t a t i o n , r e c r e a t i o n ( i n c l u d i n g s w i m m i n g a n d m o t o r i z e d a c t i v i t i e s ) , w i l d l i f e a n d m i n i n g ( P a n e l R e v i e w , 2 0 0 2 ) . N o n - p o i n t s o u r c e p o l l u t i o n i s c h a l l e n g i n g t o r e g u l a t e b e c a u s e c o n v e n t i o n a l l e g a l t o o l s a r e o n l y d e s i g n e d t o a d d r e s s p o i n t s o u r c e s o f p o l l u t i o n . A d d i t i o n a l l y , r u r a l a r e a s o f t e n d o n o t h a v e t h e s a m e r e s o u r c e s a s t h e i r u r b a n c o u n t e r p a r t s f o r p r o t e c t i n g w a t e r s o u r c e s ( D e L o e et al., 2 0 0 2 ) . T h e r e f o r e , u n d e r s t a n d i n g h o w t h e c u m u l a t i v e e f f e c t s o f d i f f e r e n t l a n d u s e s c a n i m p a c t w a t e r q u a l i t y i s e s s e n t i a l f o r r e c o m m e n d i n g a c t i o n s t o p r o t e c t r u r a l w a t e r s o u r c e s . 1.3.2 Water Treatment M o s t r u r a l h o m e o w n e r s d o n o t t rea t t h e i r d r i n k i n g w a t e r a n d r e l y s o l e l y o n t h e q u a l i t y o f t h e i r d r i n k i n g w a t e r s o u r c e s t o p r o t e c t t h e m f r o m d i s e a s e ( J a q u e s a n d R h o d e 2 0 0 1 ; S u m m e r s a n d F i t z G i b b o n , 2 0 0 3 ; L e g a u l t , 2 0 0 0 ) . D r i n k i n g w a t e r t r e a t m e n t d e a l s w i t h t h r e e t y p e s o f c o n t a m i n a n t s , m i c r o b i a l , s u c h as b a c t e r i a , v i r u s e s a n d p r o t o z o a , c h e m i c a l c o n t a m i n a n t s s u c h a s m e t a l s a n d p e s t i c i d e s a n d c o n t a m i n a t e d s e d i m e n t s a n d r a d i o l o g i c a l c o n t a m i n a n t s ( J a f f e a n d D i N o v o , 1 9 8 7 ) . I n N o r t h A m e r i c a t h e m o s t c o m m o n f o r m o f w a t e r t r e a t m e n t i s d i s i n f e c t i o n u s i n g c h l o r i n e . C h l o r i n e i s t o x i c t o m o s t w a t e r b o r n e p a t h o g e n s a n d c a n i n a c t i v a t e h a r m f u l o r d i s e a s e c a u s i n g o r g a n i s m s ( O ' C o n n o r , 2 0 0 2 a ) . I n B r i t i s h C o l u m b i a d i s i n f e c t i o n i s m a n d a t e d f o r a l l s u r f a c e w a t e r s o u r c e s a n d ( a s o f M a y 2 0 0 3 ) " g r o u n d w a t e r t ha t , i n t h e o p i n i o n o f a d r i n k i n g w a t e r o f f i c e r , i s a t r i s k o f c o n t a i n i n g p a t h o g e n s " ( B . C . R E G 2 0 0 / 2 0 0 3 ) . B e y o n d d i s i n f e c t i o n t h e r e a r e a d d i t i o n a l t r e a t m e n t b a r r i e r s s u c h as c o a g u l a t i o n , s e d i m e n t a t i o n a n d f i l t r a t i o n t h a t a r e r e c o m m e n d e d f o r s u r f a c e w a t e r o r g r o u n d w a t e r u n d e r t h e i n f l u e n c e o f s u r f a c e w a t e r w h e n c h l o r i n e d i s i n f e c t i o n a l o n e d o e s n o t p r o v i d e f o r a d e q u a t e s a f e t y . R e c e n t l y m u c h e m p h a s i s h a s b e e n p l a c e d o n t h e i m p o r t a n c e o f f i l t r a t i o n as a n a d d i t i o n t o t h e t r e a t m e n t b a r r i e r . F a i l u r e o f t r e a t m e n t c a n l e a d t o w a t e r b o r n e d i s e a s e o u t b r e a k s . T r e a t m e n t f a i l s w h e n t r e a t m e n t s y s t e m s m a l f u n c t i o n o r a s u d d e n c h a n g e i n w a t e r q u a l i t y o v e r w h e l m s t h e a b i l i t y o f t h e c h l o r i n e t o d i s i n f e c t . I n W a l k e r t o n t h e o p e r a t o r s o f t he w a t e r s y s t e m ( i n r e s p o n s e t o p u b l i c p r e s s u r e a n d b a s e d o n t h e i r o w n c o n f i d e n c e i n t he q u a l i t y o f t he w a t e r ) r o u t i n e l y d i d n o t a d d a d e q u a t e l e v e l s o f c h l o r i n e t o t h e w a t e r t o e n s u r e t ha t p a t h o g e n s w e r e k i l l e d . A t t h e t i m e o f t h e o u t b r e a k o n e w e l l d i d n o t h a v e a c h l o r i n a t o r i n s t a l l e d at a l l a n d i t w a s l a t e r r e v e a l e d t h a t t h e o p e r a t o r s h a d r o u t i n e l y 7 l i e d w h e n r e c o r d i n g t h e a m o u n t o f c h l o r i n e t ha t w a s a d d e d t o t h e s y s t e m . P a s t o u t b r e a k s i n B r i t i s h C o l u m b i a h a v e b e e n a t t r i b u t e d to p r o b l e m s w i t h t r e a t m e n t s u c h a s c h l o r i n a t o r m a l f u n c t i o n s , c h l o r i n a t o r s b e i n g t u r n e d o f f a n d i n a d e q u a t e c h l o r i n a t i o n b e i n g p r o v i d e d t o r e s i d e n t s b y r e p l a c e m e n t w o r k e r s d u r i n g a s t r i k e ( H e a l t h C a n a d a . 1 9 7 8 - 1 9 9 5 , P r o v i n c i a l H e a l t h O f f i c e r , 2 0 0 1 , C h r i s t e n s e n a n d P a r f i t t , 2 0 0 3 ) A s m e n t i o n e d p r e v i o u s l y , m o s t r u r a l w e l l o w n e r s d o n o t t r ea t t h e i r w a t e r . T h i s i s t r u e e v e n i n c a s e s w h e n t h e w e l l s h a v e k n o w n w a t e r q u a l i t y p r o b l e m s . A s t u d y o f d e t e r i o r a t i o n o f w e l l w a t e r e n v i r o n m e n t s i n A l b e r t a f o u n d t ha t " a l t h o u g h a b o u t 7 4 % o f t h e a c t i v e w e l l s w e r e r e p o r t e d t o h a v e w a t e r q u a l i t y a n d / o r q u a n t i t y p r o b l e m s , o n l y 3 1 % o f t h e s e w e l l s w e r e i d e n t i f i e d as e v e r h a v i n g r e c e i v e d a t r e a t m e n t a n d s h o c k c h l o r i n a t i o n w a s t h e o n l y t r e a t m e n t m e t h o d u s e d i n t h e s t u d y a r e a " ( L e g u a l t , 2 0 0 0 ) . A s i m i l a r s t u d y i n S a s k a t c h e w a n f o u n d t h a t " a l t h o u g h 7 6 % [ o f w e l l s ] r e p o r t e d at l e a s t o n e w a t e r q u a l i t y p r o b l e m o n l y 3 8 % o f t h e w e l l s h a v e b e e n t r e a t e d at l e a s t o n c e i n t h e i r l i f e t i m e " ( J a q u e s a n d R o h d e , 2 0 0 1 ) . I n a d d i t i o n t o t h e f a c t t ha t t r e a t m e n t i s r a r e i n s m a l l o r i n d i v i d u a l w a t e r s y s t e m s a s t u d y i n E n g l a n d f o u n d t h a t w h e n s m a l l w a t e r s y s t e m s d o e m p l o y t r e a t m e n t , i t i s o f t e n i n e f f e c t i v e b e c a u s e o f a l a c k o f m a i n t e n a n c e a n d o p e r a t i o n a l k n o w l e d g e ( R u t t e r et al, 2 0 0 0 ) . 1.3.3 Distribution System T h e w a t e r d i s t r i b u t i o n s y s t e m i s t h e n e t w o r k o f p i p e s b e t w e e n t h e s o u r c e a n d t r e a t m e n t s y s t e m a n d t h e c o n s u m e r ' s p l u m b i n g s y s t e m , a n d i n c l u d e s s t o r a g e o f t r e a t e d w a t e r i n w a t e r t o w e r s a n d r e s e r v o i r s . C o n t a m i n a t i o n o f t h e d i s t r i b u t i o n s y s t e m c a n o c c u r a s a r e s u l t o f w a t e r m a i n b r e a k s , c o n s t r u c t i o n o f n e w m a i n s o r i n f i l t r a t i o n f r o m t h e s u r r o u n d i n g g r o u n d w a t e r i n t o t h e d i s t r i b u t i o n s y s t e m p i p e s . T h e l o n g e r w a t e r i s i n t h e d i s t r i b u t i o n s y s t e m t h e g r e a t e r t h e r i s k o f a d e c r e a s e i n q u a l i t y . A n A m e r i c a n i n v e s t i g a t i o n o f t h e i n c i d e n c e o f o u t b r e a k s i n p u b l i c w a t e r s y s t e m s c a u s e d b y c o n t a m i n a t e d w a t e r e n t e r i n g t h e d i s t r i b u t i o n s y s t e m f o u n d t ha t b e t w e e n 1 9 7 1 a n d 1 9 9 8 , 1 8 . 3 % o f t he o u t b r e a k s i n t h e U n i t e d S t a t e s w e r e c a u s e d b y c h e m i c a l a n d m i c r o b i a l c o n t a m i n a n t s e n t e r i n g t h e d i s t r i b u t i o n s y s t e m ( C r a u n a n d C a l d e r o n , 2 0 0 1 ) . T h e c a u s e s o f t h e s e o u t b r e a k s w e r e l a r g e l y c r o s s - c o n n e c t i o n s , b a c k s i p h o n a g e a n d c o n t a m i n a t i o n o f d i s t r i b u t i o n s t o r a g e . W h i l e r u r a l w a t e r s y s t e m s d o n o t h a v e e x t e n s i v e d i s t r i b u t i o n s y s t e m s as d e s c r i b e d a b o v e , t h i s b a r r i e r c a n n o t b e n e g l e c t e d i n d i s c u s s i o n s o f r u r a l w a t e r s u p p l i e s . I f w e c o n s i d e r t h e r u r a l d i s t r i b u t i o n s y s t e m t o e n c o m p a s s t h e w e l l ( o r i n t a k e p i p e i n t h e c a s e o f s u r f a c e w a t e r ) a n d a l l s u b s e q u e n t p i p i n g b e t w e e n t h e w e l l a n d t h e p o i n t o f u s e ( h o m e a n d / o r b a r n ( s ) ) t h e r e a r e m a n y p o t e n t i a l a v e n u e s f o r c o n t a m i n a t i o n to o c c u r i n t h e d i s t r i b u t i o n s y s t e m . I n a d d i t i o n t o t h e 8 p r o b l e m s m e n t i o n e d a b o v e , g r o u n d w a t e r w e l l s t h e m s e l v e s c a n b e a c o n d u i t f o r c o n t a m i n a t i o n t o e n t e r a q u i f e r s . T h i s i s b e c a u s e , i n a s e n s e , w a t e r w e l l s a r e " a p u n c t u r e t h r o u g h t h e p r o t e c t i v e filter o f t he e a r t h " ( J a f f e a n d D i N o v o , 1 9 8 7 a n d S u m m e r s a n d F i t z G i b b o n , 2 0 0 3 ) . It i s i m p o r t a n t t ha t w e l l s b e p r o p e r l y c o n s t r u c t e d i n c l u d i n g p r o p e r c a s i n g a n d s e a l i n g t o a v o i d t h i s " s h o r t -c u t t i n g " o f c o n t a m i n a n t s t o a q u i f e r s . A n A m e r i c a n s t u d y f o u n d a s i g n i f i c a n t r e l a t i o n s h i p b e t w e e n l e v e l s o f c o l i f o r m s i n w e l l w a t e r a n d t h e d e p t h o f w e l l c a s i n g , f u r t h e r h i g h l i g h t i n g t h e n e e d f o r p r o p e r l y c o n s t r u c t e d d r i n k i n g w a t e r w e l l s ( T u t h i l l et al, 1 9 9 8 ) . O t h e r e x p e r t s f e e l t ha t m o s t c a s e s o f c o n t a m i n a t i o n i n w e l l s a r e c a u s e d b y p o o r c o n s t r u c t i o n o f t h e w e l l s a n d n o t f r o m w i d e s p r e a d a q u i f e r c o n t a m i n a t i o n ( S u m m e r s a n d F i t z G i b b o n , 2 0 0 3 ) . S o m e n o n - p a t h o g e n i c m i c r o o r g a n i s m s c a n a l s o r e d u c e t h e v a l u e a n d l i f e o f w a t e r w e l l s . T h i s p r o c e s s , c a l l e d b i o -f o u l i n g , c a n r e s u l t i n r e d u c e d y i e l d q u a l i t y o f w a t e r f r o m t h e w e l l ( L e g a u l t , 2 0 0 0 a n d J a q u e s a n d R o h d e , 2 0 0 1 ) . 1.3.4 Monitoring M o n i t o r i n g i n v o l v e s t a k i n g m e a s u r e m e n t s a n d c o l l e c t i n g s a m p l e s t o e n s u r e t h e w a t e r s y s t e m i s w o r k i n g p r o p e r l y . F o r m u n i c i p a l s y s t e m s t h e f r e q u e n c y o f m o n i t o r i n g i s u s u a l l y l e g i s l a t e d b a s e d o n t h e s i z e o f w a t e r s y s t e m s , b u t a s f o r t r e a t m e n t , t h e r e a r e n o l e g a l r e q u i r e m e n t s ( i n B C ) f o r i n d i v i d u a l w e l l o w n e r s t o m o n i t o r t h e i r d r i n k i n g w a t e r . M a n y r u r a l r e s i d e n t s w i l l t es t t h e i r w a t e r a t t h e t i m e a n e w w e l l i s d r i l l e d t o e n s u r e p o t a b i l i t y b u t t h e n d o n o t tes t t h e w a t e r a g a i n . T h e r e q u i r e m e n t s f o r f r e q u e n t m o n i t o r i n g o f l a r g e r w a t e r s y s t e m s a c k n o w l e d g e s t h e f a c t t ha t w a t e r q u a l i t y c a n c h a n g e e i t h e r s e a s o n a l l y d u e to a f l u c t u a t i n g w a t e r t a b l e , i n r e s p o n s e to a s t o r m o r o t h e r w a t e r s h e d e v e n t ( s u c h a s a l a n d s l i d e ) o r o v e r s e v e r a l y e a r s d u e t o c h a n g i n g l a n d u s e s s u c h a s i n c r e a s e d i n t e n s i t y o f a g r i c u l t u r e o r d e n s i t y o f h o m e s . R u r a l w e l l o w n e r s m a y b e e s p e c i a l l y v u l n e r a b l e t o t h e s e c h a n g e s a s t h e i r w a t e r s o u r c e s a r e o f t e n c l o s e t o h o m e a n d t h e s e l a n d u s e c h a n g e s c a n b e h a p p e n i n g a l l a r o u n d i n d i v i d u a l w e l l s . M o n i t o r i n g b u d g e t s a r e o f t e n l i m i t e d a n d t h e r e i s a n e n d l e s s a r r a y o f p a t h o g e n s a n d c h e m i c a l s t ha t c a n b e d e t e c t e d i n w a t e r . T i m e a n d m o n e y a r e v e r y r e a l c o n s t r a i n t s t ha t c a u s e m o n i t o r i n g e f f o r t t o f o c u s o n a r e d u c e d n u m b e r o f " i n d i c a t o r " o r g a n i s m s a n d c h e m i c a l s t h a t a r e e a s y t o m e a s u r e a n d w h o s e p r e s e n c e o r a b s e n c e m a y i n d i c a t e c o n t a m i n a t i o n w i t h o t h e r , h a r d e r t o m e a s u r e , b u t p o t e n t i a l l y m o r e d a n g e r o u s c h e m i c a l s a n d p a t h o g e n s . T h e u s e o f i n d i c a t o r s i s i m p e r f e c t ( A l l a n et al., 2 0 0 0 , C r a u n et al., 1 9 9 7 ) b u t o f t e n t h e o n l y p r a c t i c a l m e t h o d o f a s s e s s i n g w a t e r q u a l i t y . F o r e x a m p l e , m o s t w a t e r b o r n e d i s e a s e s a r e c a u s e d b y m i c r o o r g a n i s m s f o u n d i n 9 f e c a l w a s t e s a n d t h e r e f o r e i f f e c a l c o l i f o r m s a r e f o u n d i n d r i n k i n g w a t e r t h i s c o n s t i t u t e s a n u n a c c e p t a b l e r i s k ( O ' C o n n o r , 2 0 0 2 a ) . M i c r o b i a l p a r a m e t e r s s h o u l d n o t b e t h e s o l e f o c u s o f m o n i t o r i n g . O t h e r p a r a m e t e r s t ha t c a n b e m o n i t o r e d i n c l u d e w a t e r s h e d e v e n t s ( tha t m i g h t b e l i k e l y t o c a u s e c o n t a m i n a t i o n s u c h a s l a r g e s t o r m s , l a n d s l i d e s o r e v e n c o n s t r u c t i o n n e a r w a t e r s o u r c e s ) , r a t e s o f d i s e a s e i n t h e c o m m u n i t y a n d o t h e r w a t e r q u a l i t y p a r a m e t e r s s u c h as t u r b i d i t y , t o t a l d i s s o l v e d s o l i d s , t e m p e r a t u r e , a l k a l i n i t y , h a r d n e s s , p H , h y d r a u l i c f l o w r a t e s , a n d c o n d u c t i v i t y ( A l l e n et al, 2 0 0 0 ) . I n o r d e r f o r m o n i t o r i n g to b e e f f e c t i v e i t n e e d s to b e c a r r i e d o u t i n r e l a t i o n to r a i n f a l l a n d r u n o f f e v e n t s a s w e l l a s f r e q u e n t l y e n o u g h t o d e t e c t c h a n g e s i n p a r a m e t e r s t ha t m i g h t s i g n i f y a r i s k t o t h e h e a l t h o f t he p e o p l e c o n s u m i n g t h e w a t e r . 1.3.5 Response T h i s f i n a l b a r r i e r i n v o l v e s t h e a p p r o p r i a t e r e s p o n s e s to f a i l i n g p r o c e s s m e a s u r e s o r a d v e r s e w a t e r q u a l i t y . T h i s b a r r i e r i s i m p o r t a n t b e c a u s e i t i s t h e f i n a l l i n e o f d e f e n s e i f a l l t h e o t h e r b a r r i e r s f a i l a n d w a t e r b e c o m e s c o n t a m i n a t e d . I f a n o u t b r e a k i s d e t e c t e d i n t h e c o m m u n i t y r a p i d r e s p o n s e c a n l i m i t o f t he s c o p e o f t h e o u t b r e a k . T h e m o s t c o m m o n r e s p o n s e t o h i g h e r t h a n a c c e p t a b l e l e v e l s o f b a c t e r i a i n w a t e r a n d c o m m u n i t y g a s t r o i n t e s t i n a l d i s e a s e o u t b r e a k s i s f o r t h e m e d i c a l o f f i c e r o f h e a l t h t o i s s u e a " b o i l w a t e r o r d e r " . T h i s a l e r t s t h e p u b l i c t o t h e f a c t t ha t t h e w a t e r i s c o n t a m i n a t e d w i t h b a c t e r i a o r o t h e r m i c r o b i a l p a r a m e t e r s a n d s h o u l d n o t b e c o n s u m e d u n l e s s b o i l e d f o r 5 m i n u t e s . I n g e n e r a l , i s s u i n g a b o i l w a t e r o r d e r i s a v e r y s e r i o u s d e c i s i o n as u n w a r r a n t e d b o i l w a t e r a d v i s o r i e s c a n h a v e d r a s t i c e c o n o m i c a n d s o c i a l c o n s e q u e n c e s as w e l l a s t h e p o t e n t i a l t o u n d e r m i n e t h e f u t u r e c r e d i b i l i t y o f t h e h e a l t h u n i t i s s u i n g t h e a d v i s o r y o n t h e a r e a f o r w h i c h i t i s o r d e r e d . T h e r e a r e s e v e r a l f a c t o r s t ha t m u s t b e t a k e n i n t o a c c o u n t w h e n r e s p o n d i n g to a d v e r s e m o n i t o r i n g r e s u l t s ; d o t h e m o n i t o r i n g r e s u l t s c o r r e s p o n d t o a n i n c r e a s e i n i l l n e s s i n t h e c o m m u n i t y ? C o n v e r s e l y , i f p e o p l e i n t h e c o m m u n i t y a r e i l l a n d t h e r e h a v e n ' t b e e n a d v e r s e w a t e r q u a l i t y r e p o r t s , c a n a l i n k b e m a d e f r o m t h e i l l n e s s to t h e c o m m u n i t y w a t e r s o u r c e ? T h e r e h a v e b e e n c a s e s w h e r e o u t b r e a k s h a v e b e e n d i s c o v e r e d t h r o u g h c l i n i c a l m o n i t o r i n g r a t h e r t h a n t h r o u g h r o u t i n e m o n i t o r i n g o f w a t e r q u a l i t y a n d c a s e s w h e r e t h e r o u t i n e m o n i t o r i n g w a s p o o r l y c a r r i e d o u t , w a t e r q u a l i t y w a s t h o u g h t t o b e c o m p r o m i s e d a n d b o i l w a t e r o r d e r s w e r e i s s u e d w i t h n o c o r r e s p o n d i n g e v i d e n c e o f i n c r e a s e s i n i l l n e s s i n t he c o m m u n i t y ( A l l e n et al, 2 0 0 0 ) . It m u s t a l s o b e k e p t i n m i n d t h a t a b o i l w a t e r a d v i s o r y i s o n l y i s s u e d i n c a s e s w h e r e t h e p r o b l e m w i t h t h e w a t e r i s b i o l o g i c a l . I f t h e w a t e r h a s 10 b e e n i m p a c t e d b y o t h e r c h e m i c a l s t h i s m a y b e a n i n a p p r o p r i a t e r e s p o n s e ( i n t h e c a s e o f h i g h n i t r a t e v a l u e s , b o i l i n g w a t e r w i l l c o n c e n t r a t e t h e c h e m i c a l r a t h e r t h a n d i s p e r s i n g i t ) . B e c a u s e p r i v a t e w e l l o w n e r s r a r e l y t r ea t t h e i r w a t e r a n d r a r e l y m o n i t o r i t , t h e r e i s n o t o f t e n a c h a n c e t o r e s p o n d t o a d v e r s e r e s u l t s . A d d i t i o n a l l y , e n d e m i c i l l n e s s i n r e s i d e n t s o n p r i v a t e w a t e r s u p p l i e s a r e o f t e n n o t l i n k e d t o w a t e r e v e n t h o u g h m a n y e x p e r t s f e e l t ha t w a t e r m a y b e t h e c a u s e o f m u c h g a s t r o i n t e s t i n a l i l l n e s s ( R u t t e r et al., 2 0 0 0 ) . 1.4 Nitrate and Pathogens - Contaminants of Concern W h e n e x a m i n i n g t h e i m p a c t s o f l a n d u s e o n r u r a l g r o u n d w a t e r w e l l s a n d a q u i f e r s i t q u i c k l y b e c o m e s a p p a r e n t t ha t n i t r a t e a n d p a t h o g e n s a re t h e m o s t f r e q u e n t l y d e t e c t e d c o n t a m i n a n t s tha t m a y i m p a c t h u m a n h e a l t h ( C o o t e a n d G r e g o r i c h , 2 0 0 0 ; G o s s et al, 1 9 9 8 ; R u d o l p h et al., 1 9 9 8 ; R e i d et al., 2 0 0 2 ) . N i t r a t e a n d p a t h o g e n s e n t e r g r o u n d w a t e r f r o m a v a r i e t y o f s o u r c e s , t h e m o s t c o m m o n b e i n g m a n u r e a n d f e r t i l i z e r a p p l i c a t i o n s t o a g r i c u l t u r a l l a n d s a n d f r o m s e p t i c s y s t e m s , e s p e c i a l l y i n u n - s e w e r e d r u r a l s u b d i v i s i o n s ( C o o t e a n d G r e g o r i c h , 2 0 0 0 ; D a k i n , 1 9 9 4 ; C a r m i c h a e l et al, 1 9 9 5 ; S c h r e i e r et al, 1 9 9 6 ; L i e b s c h e r et al, 1 9 9 2 ) . 1.4.1 Nitrate N i t r a t e ( N 0 3 " ) i s a h i g h l y s o l u b l e n i t r o g e n a n i o n t ha t i s n o t u s u a l l y a d s o r b e d t o s o i l p a r t i c l e s ( t h e t e r m i n o l o g y N i t r a t e - N i s u s e d to r e f e r t o o n l y t h e n i t r o g e n p a r t o f t h e n i t r a t e m o l e c u l e w h e n d i s c u s s i n g l e v e l s o f n i t r a t e i n g r o u n d w a t e r , h o w e v e r , t h r o u g h o u t t h i s r e p o r t n i t r a t e i s u s e d i n t e r c h a n g e a b l y w i t h n i t r a t e - N w h e n r e f e r r i n g t o s p e c i f i c m e a s u r e m e n t s o f t h i s n u t r i e n t . ) S u p p l y i n g c r o p s w i t h a d e q u a t e n i t r o g e n i s v i t a l t o e n s u r i n g f o o d s u p p l i e s b o t h n a t i o n a l l y a n d i n t e r n a t i o n a l l y ; h o w e v e r , a d d i t i o n o f n i t r o g e n f e r t i l i z e r o r m a n u r e t o f a r m f i e l d s i n e x c e s s o f t ha t r e q u i r e d f o r c r o p s w i l l r e s u l t i n l o s s o f n i t r a t e f r o m t h e r o o t z o n e b y l e a c h i n g ( F o l l e t t , 1 9 8 9 ) . N i t r a t e i s a h u m a n h e a l t h c o n c e r n b e c a u s e i t h a s b e e n a s s o c i a t e d w i t h m e t h e m o g l o b i n e m i a , a c o n d i t i o n i n w h i c h n i t r a t e i s c o n v e r t e d i n t h e g u t t o n i t r i t e , w h i c h t h e n c o m b i n e s w i t h h e m o g l o b i n t o f o r m m e t h e m o g l o b i n , t h u s d e c r e a s i n g t h e a b i l i t y o f t h e b l o o d t o c a r r y o x y g e n . I n f a n t s l e s s t h a n t h r e e m o n t h s o f a g e a r e m o s t s u s c e p t i b l e t o t h i s s o m e t i m e s - f a t a l c o n d i t i o n , w h i c h i s a l s o c a l l e d " B l u e B a b y S y n d r o m e " . N i t r a t e h a s a l s o b e e n a s s o c i a t e d w i t h c e r t a i n t y p e s o f c a n c e r a l t h o u g h t h e r e a r e n o c o n c l u s i v e l i n k s b e t w e e n i n g e s t i n g n i t r a t e a n d i n c i d e n c e o f c a n c e r ( F o l l e t t , 1 9 8 9 ; C o o t e a n d G r e g o r i c h , 2 0 0 0 ; N o l a n a n d S t o n e r ; 2 0 0 0 ) . 11 T h e m a x i m u m a l l o w a b l e c o n c e n t r a t i o n ( M A C ) f o r n i t r a t e i n t h e G u i d e l i n e s f o r C a n a d i a n D r i n k i n g W a t e r Q u a l i t y ( G C D W Q ) i s 1 0 m g / L n i t r a t e as n i t r o g e n . H o w e v e r , s i n c e b a c k g r o u n d l e v e l s o f n i t r a t e i n g r o u n d w a t e r a r e g e n e r a l l y l e s s t h a n 2 m g / L w e u s e 3 m g / L as a n i n d i c a t i o n tha t t h e g r o u n d w a t e r h a s b e e n i m p a c t e d o r i s u n d e r t he i n f l u e n c e o f s u r f a c e w a t e r ( C o o t e a n d G r e g o r i c h , 2 0 0 0 ; S c h r e i e r et al, 1 9 9 6 ; C a r m i c h a e l et ai, 1 9 9 5 ) . I f g r o u n d w a t e r h a s l e v e l s o f n i t r a t e a b o v e 3 m g / L i t i s a n i n d i c a t i o n t ha t t h e d r i n k i n g w a t e r m a y b e c o n t a m i n a t e d o t h e r s u b s t a n c e s o f c o n c e r n . 1.4.2 Conforms A s m e n t i o n e d i n s e c t i o n 1.3.4 ( m o n i t o r i n g ) , i t i s i m p o s s i b l e t o t es t d r i n k i n g w a t e r f o r e v e r y p a r a m e t e r t ha t m i g h t a d v e r s e l y i m p a c t h u m a n h e a l t h ; t h i s i s e s p e c i a l l y t r u e o f d i s e a s e c a u s i n g m i c r o o r g a n i s m s . F o r t h i s r e a s o n , i n d i c a t o r o r g a n i s m s a r e m e a s u r e d t o i n d i c a t e t h e p o t e n t i a l f o r c o n t a m i n a t i o n . T h e m o s t c o m m o n i n d i c a t o r i s t h e c o l i f o r m g r o u p o f b a c t e r i a . T o t a l c o l i f o r m s i n c l u d e s p e c i e s o f b a c t e r i a t ha t o f t e n i n h a b i t i n t e s t i n e s o f w a r m - b l o o d e d a n i m a l s as w e l l as s o m e b a c t e r i a tha t a l s o o c c u r n a t u r a l l y i n t h e e n v i r o n m e n t a n d a r e u s u a l l y n o t p a t h o g e n i c . I f t o t a l c o l i f o r m s a r e p r e s e n t i n t r e a t e d d r i n k i n g w a t e r t h i s m a y i n d i c a t e a t r e a t m e n t f a i l u r e o r c o n t a m i n a t i o n e v e n t , h o w e v e r , p r e s e n c e o f t o t a l c o l i f o r m s d o e s n o t n e c e s s a r i l y i n d i c a t e t ha t p a t h o g e n i c o r g a n i s m s a r e p r e s e n t . F e c a l c o l i f o r m s a r e a t h e r m o t o l e r a n t s u b - g r o u p o f t o t a l c o l i f o r m s . T h e s e b a c t e r i a c a n s u r v i v e a t h i g h e r t e m p e r a t u r e s a n d a r e o n l y a s s o c i a t e d w i t h t h e f e c a l m a t e r i a l o f w a r m - b l o o d e d a n i m a l s , t h u s t h e p r e s e n c e o f f e c a l c o l i f o r m s i n a w a t e r s a m p l e i n d i c a t e s t ha t t h e w a t e r h a s b e e n c o n t a m i n a t e d w i t h t h e f e c a l m a t t e r o f h u m a n s o r a n i m a l s . T h e p r e s e n c e o f f e c a l c o n t a m i n a t i o n i s a n i n d i c a t o r o f a h i g h e r d e g r e e o f p o t e n t i a l r i s k f o r i n d i v i d u a l s e x p o s e d t o t h i s w a t e r . R e s e a r c h h a s s h o w n ( R e y n o l d s , 2 0 0 3 ) t h a t > 9 0 % o f t h e p o p u l a t i o n o f t o t a l c o l i f o r m b a c t e r i a i n h u m a n a n d a n i m a l f e c e s i s Escherichia coli. T h e r e f o r e E. coli i s c o n s i d e r e d t h e m o s t a c c u r a t e i n d i c a t o r o f f e c a l c o n t a m i n a t i o n i n w a t e r . A g a i n i t m u s t b e k e p t i n m i n d t ha t t h e p r e s e n c e o f E. coli i n d r i n k i n g w a t e r d o e s n o t g u a r a n t e e t h a t w a t e r i s c o n t a m i n a t e d ( m a n y s u b - s p e c i e s o f E. coli a r e h a r m l e s s ) b u t s i m p l y i n d i c a t e s i n c r e a s e d r i s k . M o s t e x p e r t s r e c o m m e n d b o i l i n g w a t e r t ha t h a s t e s t e d p o s i t i v e f o r f e c a l c o l i f o r m s o r E.coli i n o r d e r t o m i n i m i z e t h e r i s k c o n t r a c t i n g g a s t r o i n t e s t i n a l i l l n e s s . T o t a l a n d f e c a l c o l i f o r m s a n d E. coli a r e n o t p e r f e c t i n d i c a t o r s . T h e y h a v e n o t p r o v e n e f f e c t i v e at p r e d i c t i n g t h e p r e s e n c e o f v i r a l o r p r o t o z o a n c o n t a m i n a t i o n . L a r g e o u t b r e a k s o f d i s e a s e c a u s e d b y p r o t o z o a n p a r a s i t e s s u c h a s Giradia a n d Cryptosporidium h a v e o c c u r r e d i n c o m m u n i t i e s w h e r e n o n e g a t i v e r e s u l t s f o r c o l i f o r m s w e r e d e t e c t e d . T h e m o s t n o t a b l e o f t h e s e w a s a n 12 o u t b r e a k o f c i y p t o s p o r i d i o s i s i n M i l w a u k e e , W i s c o n s i n i n 1 9 9 3 . D e s p i t e t h e s e l i m i t a t i o n s , m e a s u r e m e n t s o f t o t a l a n d f e c a l c o l i f o r m s r e m a i n o n e o f t h e m o s t i m p o r t a n t a n d w i d e l y u s e d m e a s u r e s o f p o t e n t i a l m i c r o b i a l c o n t a m i n a t i o n a n d h a v e b e e n e f f e c t i v e i n p r e v e n t i n g o u t b r e a k s o f c h o l e r a , t y p h o i d f e v e r a n d v a r i o u s g a s t r o i n t e s t i n a l d i s e a s e s . T h e r e a r e c u r r e n t l y n o g u i d e l i n e s f o r l e v e l s o f t h e p a r a s i t e s Giardia sp.or Cryptosporidium sp. n o r a r e t h e r e a n y g u i d e l i n e s f o r l e v e l s o f v i r u s e s d u e t o t h e d i f f i c u l t y , e x p e n s e a n d u n r e l i a b i l i t y o f c u r r e n t d e t e c t i o n m e t h o d s . T h e C a n a d i a n w a t e r q u a l i t y g u i d e l i n e s f o r b a c t e r i a a r e c u r r e n t l y u n d e r r e v i e w b u t s ta te t ha t z e r o f e c a l c o l i f o r m s s h o u l d b e d e t e c t e d i n 1 0 0 m l o f s a m p l e a n d n o m o r e t h a n 10 t o t a l c o l i f o r m s i n 1 0 0 m l ( o f w h i c h n o n e s h o u l d b e E.coli o r t h e r m o t o l e r a n t b a c t e r i a ) . T h e v u l n e r a b i l i t y o f s u r f a c e w a t e r t o p a t h o g e n c o n t a m i n a t i o n h a s l o n g b e e n r e c o g n i z e d , l e a d i n g t o t h e d i s i n f e c t i o n b y c h l o r i n e o f s u r f a c e w a t e r i n B e l g i u m s i n c e 1 9 0 2 . S i n c e t h e n , d i s i n f e c t i o n h a s b e c o m e a s t a n d a r d p u b l i c h e a l t h p r a c t i c e c r e d i t e d w i t h s a v i n g m i l l i o n s o f l i v e s a r o u n d t h e w o r l d ( B e n i d i c k s o n , 2 0 0 2 ; H i l l e l , 1 9 9 8 ) . G r o u n d w a t e r , o n t h e o t h e r h a n d , w a s l o n g t h o u g h t t o b e p r o t e c t e d f r o m t h e b a c t e r i a t ha t i n h a b i t s u r f a c e w a t e r w i t h p a p e r s p u b l i s h e d a s r e c e n t l y a s ( 1 9 9 9 ) c l a i m i n g t h a t " u n t r e a t e d g r o u n d w a t e r i s f r e e f r o m f e c a l c o n t a m i n a t i o n as a r e s u l t o f p a s s a g e t h r o u g h s o i l o v e r e x t e n d e d p e r i o d s o f t i m e " ( V a n D e r K o o i j et al, 1 9 9 9 ) . T h e W a l k e r t o n e x p e r i e n c e i s b u t o n e d r a m a t i c e x a m p l e t ha t s h o w s t ha t g r o u n d w a t e r c a n b e v u l n e r a b l e t o b a c t e r i a l c o n t a m i n a t i o n . M a n y o t h e r s t u d i e s h a v e l i n k e d d i s e a s e o u t b r e a k s , i l l n e s s a n d c o n t a m i n a t i o n e v e n t s w i t h g r o u n d w a t e r f r o m b o t h p u b l i c a n d p r i v a t e w e l l s . ( H a s s , 1 9 9 9 ; C r a u n a n d C a l d e r o n , 2 0 0 1 ; L i p p y a n d W a l t r i p , 1 9 8 4 ; B o r c h a r d t et al, 2 0 0 3 ) . C l e a r l y b a c t e r i a l c o n t a m i n a t i o n i s a c o n c e r n i n b o t h s u r f a c e a n d g r o u n d w a t e r . 1.4.3 Nitrate: A useful indicator for coliform contamination? S e v e r a l s t u d i e s i n O n t a r i o a n d t h e U . K . h a v e s h o w n tha t i n g e n e r a l , p r i v a t e w e l l s e x c e e d w a t e r q u a l i t y g u i d e l i n e s m o r e o f t e n f o r t o t a l a n d f e c a l c o l i f o r m s t h a n f o r n i t r a t e . A d d i t i o n a l l y t h e r e i s o f t e n l i t t l e c o r r e l a t i o n b e t w e e n t he w e l l s t ha t e x c e e d t h e l e v e l f o r b o t h . F o r e x a m p l e , a s t u d y o f p r i v a t e w e l l s i n O n t a r i o f o u n d t ha t o f 1 2 9 2 w e l l s s a m p l e s i n 1 9 9 1 a n d 1 9 9 2 3 4 % w e r e a b o v e t h e a c c e p t a b l e l i m i t f o r c o l i f o r m s a n d 1 4 % w e r e a b o v e 10 m g / L N 0 3 - N . O n l y 7 % e x c e e d e d t h e M A C f o r b o t h ( G o s s et al, 1 9 9 8 ) . A s i m i l a r O n t a r i o s t u d y u s i n g m u l t i - l e v e l m o n i t o r i n g w e l l s a t 1 4 4 f a r m s t h r o u g h o u t t h e p r o v i n c e f o u n d t ha t 2 3 % o f s i t e s h a d c o n c e n t r a t i o n s i n 5 0 % o r m o r e o f t h e m o n i t o r e d i n t e r v a l s tha t e x c e e d e d t h e M A C f o r N 0 3 - N i n b o t h s a m p l i n g p e r i o d s . I n t h e s a m e s t u d y t o t a l c o l i f o r m l e v e l s w e r e e x c e e d e d b y 6 6 % o f w e l l s i n w i n t e r a n d 3 6 % i n s u m m e r . T h i s s t u d y a l s o f o u n d a c l e a r t r e n d o f d e c r e a s i n g N 0 3 - N w i t h d e p t h b u t n o s i m i l a r t r e n d w i t h c o l i f o r m 13 c o n t a m i n a t i o n - w h i c h r e m a i n e d r e l a t i v e l y s i m i l a r r e g a r d l e s s o f d e p t h ( R u d o l p h , 1 9 9 8 ) . A U K s t u d y t ha t e x a m i n e d 1 7 5 0 w e l l s b e t w e e n 1 9 9 2 a n d 1 9 9 8 f o u n d t h e f a i l u r e r a t e f o r t o t a l c o l i f o r m s t o b e 4 1 % , 3 0 % f o r f e c a l c o l i f o r m s a n d 1 5 % f o r n i t r a t e . L e s s t h a n 5 0 o f t h e w e l l s s a m p l e d f a i l e d f o r b o t h n i t r a t e a n d c o l i f o r m s ( R e i d et al, 2 0 0 2 ) . T h e s t u d i e s m e n t i o n e d a b o v e w o u l d s e e m t o s u g g e s t t ha t n i t r a t e i s n o t a v i a b l e i n d i c a t o r o f c o l i f o r m c o n t a m i n a t i o n . I n e v e r y s t u d y t h e n u m b e r o f c o l i f o r m f a i l u r e s e x c e e d s t h e n u m b e r o f n i t r a t e f a i l u r e s a n d t h e r e a p p e a r s t o b e l i t t l e c o r r e l a t i o n b e t w e e n t h e w e l l s t ha t f a i l f o r n i t r a t e a n d t h o s e t ha t f a i l f o r c o l i f o r m s . It m u s t b e k e p t i n m i n d , h o w e v e r t ha t i n m o s t p l a c e s d e t e c t i o n o f f e c a l c o l i f o r m b a c t e r i a i s c o n s i d e r e d a f a i l u r e w h e r e a s t h e 10 m g / L f a i l u r e l e v e l f o r N 0 3 - N i s m u c h h i g h e r t h a n t h e d e t e c t i o n l i m i t a n d a l s o q u i t e a b i t h i g h e r t h a n t h e 3 m g / L l e v e l c o n s i d e r e d b y m o s t t o b e i n d i c a t i v e o f g r o u n d w a t e r t ha t i s u n d e r t he i n f l u e n c e o f s u r f a c e w a t e r . I n t e r m s o f e s t a b l i s h i n g a l i n k b e t w e e n n i t r a t e l e v e l s a n d c o l i f o r m c o n t a m i n a t i o n t h e a b o v e s t u d i e s w o u l d b e m o r e u s e f u l i f t h e y r e p o r t e d t h e p e r c e n t a g e o f n i t r a t e l e v e l s a b o v e 3 m g / L a s w e l l as n i t r a t e f a i l u r e s w h e n c o m p a r i n g t h e s e t o c o l i f o r m l e v e l s . T h e r e f o r e , a l t h o u g h t h e a b o v e s t u d i e s s e e m t o s u g g e s t t ha t n i t r a t e i s n o t a u s e f u l i n d i c a t o r f o r c o l i f o r m c o n t a m i n a t i o n , f u l l r e p o r t i n g o f n i t r a t e r e s u l t s w o u l d b e m o r e u s e f u l w h e n a t t e m p t i n g t o e s t a b l i s h w h e t h e r o r n o t a u s e f u l l i n k e x i s t s b e t w e e n t h e s e t w o p a r a m e t e r s . T h e f a c t r e m a i n s tha t i t i s e a s i e r a n d c h e a p e r t o m e a s u r e n i t r a t e l e v e l s t h a n c o l i f o r m l e v e l s i n d r i n k i n g w a t e r s u p p l i e s . 1.5 Other Water Quality Parameters 1.5.1 Iron and Manganese I r o n ( F e ) a n d m a n g a n e s e ( M n ) a r e n o n - h a z a r d o u s e l e m e n t s tha t c a n b e a n u i s a n c e i n w a t e r s u p p l i e s . T h e e l e m e n t s a r e c h e m i c a l l y s i m i l a r a n d c a u s e s i m i l a r p r o b l e m s i n d r i n k i n g w a t e r i n c l u d i n g o b j e c t i o n a b l e t as te a n d o d o u r as w e l l as s t a i n i n g o f f i x t u r e s , d i s h e s a n d l a u n d r y . W a t e r w i t h h i g h l e v e l s o f i r o n a n d m a n g a n e s e i s n o t c o n s i d e r e d h a z a r d o u s t o h u m a n h e a l t h a n d t h e s o u r c e s o f t h e s e e l e m e n t s a r e n o t g e n e r a l l y a n t h r o p o g e n i c i n n a t u r e . W a t e r ( e s p e c i a l l y w i t h l o w p H ) d i s s o l v e s F e a n d M n a s i t p e r c o l a t e s t h r o u g h s o i l a n d r o c k a n d h o l d s t h e d i s s o l v e d f o r m s o f t h e s e m e t a l s i n s o l u t i o n . W a t e r w i t h h i g h l e v e l s o f F e a n d M n i s t y p i c a l l y c l e a r a n d c o l o u r l e s s u n t i l e x p o s e d t o o x y g e n (O2). E x p o s u r e t o o x y g e n c a u s e s t h e m e t a l s t o b e o x i d i z e d a n d c h a n g e t o c o l o u r e d s o l i d f o r m s . T h e o x i d i z e d f o r m s o f F e a n d M n a re v i s i b l e a s p a r t i c u l a t e m a t t e r a n d c a u s e t he w a t e r q u a l i t y p r o b l e m s m e n t i o n e d a b o v e . A d d i t i o n a l l y , o x i d i z e d F e a n d / o r M n c a n b u i l d u p s o l i d d e p o s i t s i n p i p e s a n d o t h e r f i x t u r e s , e v e n t u a l l y r e d u c i n g w a t e r p r e s s u r e a n d i n c r e a s i n g p u m p i n g c o s t s . F i n a l l y , t h e r e a r e b a c t e r i a a s s o c i a t e d w i t h h i g h l e v e l s o f i r o n w h i c h 1 4 c a u s e s l i m e b u i l d u p i n p i p e s a n d f i x t u r e s . S h o c k c h l o r i n a t i o n i s r e q u i r e d t o c o n t r o l i r o n b a c t e r i a . T h e G C D W Q a r e 0 . 3 m g / L f o r i r o n a n d 0 . 0 5 m g / L f o r m a n g a n e s e . T h e s e a r e a e s t h e t i c o b j e c t i v e s o n l y , w a t e r e x c e e d i n g t h e s e p a r a m e t e r s a r e l i k e l y t o c a u s e t h e t a s t e , o d o u r a n d s t a i n i n g p r o b l e m s m e n t i o n e d a b o v e b u t a r e n o t l i k e l y t o a d v e r s e l y a f f e c t t h e h e a l t h o f t h o s e d r i n k i n g i t . 1.5.2 Electrical Conductivity T h e e l e c t r i c a l c o n d u c t i v i t y ( E C ) i s a m e a s u r e o f w a t e r ' s a b i l i t y t o c o n d u c t c u r r e n t a n d p r o v i d e s a n e s t i m a t e o f t h e a m o u n t o f t o t a l d i s s o l v e d s a l t s i n t h e w a t e r s a m p l e . T h e g r e a t e r t h e c o n t e n t o f i o n s i n t h e w a t e r , t h e m o r e c u r r e n t t h e w a t e r c a n c a r r y ; t h e r e f o r e , c o n d u c t i v i t y l e v e l s a r e o f t e n h i g h l y c o r r e l a t e d w i t h l e v e l s o f p a r a m e t e r s s u c h as c a l c i u m , m a g n e s i u m a n d / o r s i l i c o n . T h e m e a s u r e m e n t o f c o n d u c t i v i t y r e p r e s e n t s a n a g g r e g a t e m e a s u r e o f a l l d i s s o l v e d i o n s i n t h e s a m p l e a n d i s t h e r e f o r e i n f l u e n c e d b y m a n y e l e m e n t s a n d f a c t o r s , s o m e n a t u r a l a n d s o m e a n t h r o p o g e n i c . T h e g e o l o g y o f t h e s u r r o u n d i n g a r e a w i l l h a v e a l a r g e i m p a c t o n t h e c o n d u c t i v i t y o f a w a t e r s a m p l e . F o r e x a m p l e , g r o u n d w a t e r f l o w i n g t h r o u g h l i m e s t o n e w i l l h a v e h i g h e r c o n d u c t i v i t y t h a n w a t e r f l o w i n g o v e r g r a n i t e b e c a u s e l i m e s t o n e i s m u c h m o r e s o l u b l e t h a n t h e f o r m e r . A n t h r o p o g e n i c a c t i v i t i e s c a n i n c r e a s e c o n d u c t i v i t y b y t h e a d d i t i o n o f m o r e d i s s o l v e d s a l t s i n t o a w a t e r s y s t e m . T h e a c t i v i t i e s m e n t i o n e d a b o v e , s u c h a s u s e o f c o m m e r c i a l f e r t i l i z e r o r s p r e a d i n g o f m a n u r e , t ha t i n c r e a s e n i t r a t e l e v e l s c a n a l s o i n c r e a s e c o n d u c t i v i t y l e v e l s . T h e r e a r e n o w a t e r q u a l i t y g u i d e l i n e s f o r c o n d u c t i v i t y . 1.5.3 Orthophosphate (PO/'J T h e r e i s n o h e a l t h s t a n d a r d f o r p h o s p h o r u s i n d r i n k i n g w a t e r , h o w e v e r , e l e v a t e d P l e v e l s a r e a c o n c e r n i n s u r f a c e w a t e r , e s p e c i a l l y i n l a k e s w h e r e t o o m u c h P c a u s e s e n h a n c e d p r o d u c t i o n o f a l g a e w h i c h , a s i t d e c o m p o s e s , c o n s u m e s d i s s o l v e d o x y g e n l e a d i n g t o c o n d i t i o n s w h i c h a r e s t r e s s f u l o r l e t h a l t o c e r t a i n f i s h s p e c i e s . T h i s p r o c e s s o f n u t r i e n t e n r i c h m e n t i s c a l l e d e u t r o p h i c a t i o n . O r t h o p h o s p h a t e ( P 0 4 3 ) i s a f o r m o f p h o s p h o r u s t ha t i s r e a d i l y a v a i l a b l e t o t h e b i o l o g i c a l c o m m u n i t y a n d i s t y p i c a l l y f o u n d i n v e r y l o w c o n c e n t r a t i o n s i n u n p o l l u t e d w a t e r . P 0 4 c a n b e p r o d u c e d b y n a t u r a l p r o c e s s e s o r t h r o u g h m a n m a d e i n f l u e n c e . A n t h r o p o g e n i c s o u r c e s i n c l u d e p a r t i a l l y t r e a t e d a n d u n t r e a t e d s e w a g e , a g r i c u l t u r a l r u n - o f f a n d s o m e l a w n f e r t i l i z e r s ( W e t z e l , 2 0 0 1 ) . A l t h o u g h t h e r e a r e n o g u i d e l i n e s f o r P o r P 0 4 i n d r i n k i n g w a t e r t h e r e a r e g u i d e l i n e s f o r t h e p r e v e n t i o n o f e u t r o p h i c a t i o n . T o t a l p h o s p h o r u s l e v e l s a b o v e 0 . 0 1 m g / L i n l a k e s a r e c o n s i d e r e d p r o b l e m a t i c ; f o r s t r e a m s , a m o r e c o n s e r v a t i v e g u i d e l i n e o f 0 .1 m g / L i s o f t e n u s e d 15 ( S c h r e i e r et al, 1 9 9 6 ) . O r t h o p h o s p h a t e i s o f t e n t h e f o r m o f P m e a s u r e d i n w a t e r s a m p l e s b e c a u s e i t i s t h e m o s t a v a i l a b l e f o r m ( m a n y f o r m s o f P a r e h i g h l y i n s o l u b l e a n d t e n d t o b i n d t o s e d i m e n t s r a t h e r t h a n d i s s o l v e i n t h e w a t e r c o l u m n ) . P 0 4 i s a m e a s u r e m e n t o f p a r t o f t h e t o t a l p h o s p h o r u s w h i c h m e a n s t ha t i f P 0 4 l e v e l s a r e a b o v e t h e g u i d e l i n e t h e n t h e t o t a l p h o s p h o r u s i s e v e n h i g h e r t h a n tha t . B e c a u s e o f i t s i n s o l u b l e n a t u r e , P i s n o t g e n e r a l l y c o n s i d e r e d a p r o b l e m i n g r o u n d w a t e r . T h e a v e r a g e l e v e l o f t o t a l P i n u n p o l l u t e d g r o u n d w a t e r i s a b o u t 0 . 0 2 m g / L ( W e t z e l , 2 0 0 1 ) . T h i s l e v e l w i l l v a r y d e p e n d i n g o n t h e a m o u n t o f p h o s p h o r u s i n t h e s u b s t r a t e . 1.6 Groundwater in the Lower Fraser Valley A s m e n t i o n e d i n s e c t i o n 1 . 3 . 1 b , s e v e r a l g r o u n d w a t e r a q u i f e r s i n t h e L o w e r F r a s e r V a l l e y a r e k n o w n t o b e c o n t a m i n a t e d w i t h n i t r a t e - N . H i g h n i t r a t e l e v e l s ( u p t o 4 5 m g / L ) i n t h e H o p p i n g t o n a n d A b b o s t f o r d a q u i f e r s h a v e b e e n i d e n t i f i e d a n d s t u d i e d i n s e v e r a l r e p o r t s ( S c h r e i e r et al, 1 9 9 6 , L i e b s c h e r et al, 1 9 9 2 ; Z e b a r t h e / a / . , 1 9 9 8 ) . W h i l e m o s t r e s e a r c h o n g r o u n d w a t e r q u a l i t y i n t h e L o w e r F r a s e r V a l l e y h a s f o c u s e d o n t h e a q u i f e r s m e n t i o n e d a b o v e , o n e c o m p r e h e n s i v e s t u d y l o o k e d a t 1 9 2 c o m m u n i t y w e l l s a n d 7 5 p r i v a t e w e l l s t h r o u g h o u t t h e e n t i r e F r a s e r L o w l a n d a n d c o m p a r e d t h e q u a l i t y t h r o u g h o u t . T a b l e 2 s h o w s t he n u m b e r o f e x c e e d a n c e s o f s e l e c t e d p a r a m e t e r s m e a s u r e d i n t h i s s t u d y ( C a r m i c h a e l et al, 1 9 9 5 ) . T h i s s t u d y c o n c l u d e d t h a t e l e v a t e d l e v e l s o f n i t r a t e - N o c c u r m o s t l y i n h i g h l y v u l n e r a b l e , u n c o n f i n e d a q u i f e r s i n a r e a s o f i n t e n s e h u m a n a c t i v i t y a n d t ha t e l e v a t e d n i t r a t e l e v e l s a r e d u e t o h u m a n a c t i v i t i e s . I n a d d i t i o n t o t h e 2 7 w e l l s w h i c h h a d n i t r a t e a b o v e h e a l t h s t a n d a r d s 6 2 w e l l s ( 2 6 % ) h a d n i t r a t e a t l e v e l s a b o v e 3 m g / L i n d i c a t i n g d e g r a d a t i o n o f g r o u n d w a t e r f r o m h u m a n a c t i v i t i e s . H i g h l e v e l s o f F e a n d M n a r e a n o t h e r w e l l k n o w n w a t e r q u a l i t y p r o b l e m i n t h e L o w e r F r a s e r V a l l e y a n d t h e s e p a r a m e t e r s h a v e b e e n c a l l e d " t h e m o s t t r o u b l e s o m e w a t e r q u a l i t y p a r a m e t e r s i n t h e F r a s e r L o w l a n d " ( D a k i n , 1 9 9 4 ) . Table 2. Number of well exceeding the Guidelines for Canadian Drinking Water Quality, Carmichael et al. (1995) Parameter M A C (GCDWQ) Phase 1 (239 wells sampled) Phase 2 (240 wells sampled) Iron (Fe) 0.3 mg/L 38 (16%) 31 (13%) Copper (Cu) 1 mg/L 5 (2%) 2 (1%) Zinc (Zn) 5 mg/L - 1 (0.4%) Manganese (Mn) 0.05 mg/L 54 (23%) 59 (24%) Sodium (Na) 200 mg/L 1 (0.4%) 4 (2%) PH 6.5-8.5 pH units 30 (13%) 31 (13%) Nitrate-N (N0 3-N) 10 mg/L 23 (10%) 27(11%) GCDWQ = Guidelines for Canadian Drinking Water Quality MAC = Maximum Allowable Concentration 16 2.0 Research Location 2.1 Introduction to Hatzic Valley T h e f i e l d r e s e a r c h t o i n v e s t i g a t e t h e i s s u e s r a i s e d i n c h a p t e r 1 w a s c o n d u c t e d i n t h e H a t z i c w a t e r s h e d , l o c a t e d i n t he F r a s e r L o w l a n d a r e a o f B r i t i s h C o l u m b i a ( B C ) , C a n a d a . T h e a r e a w a s c h o s e n f o r s t u d y f o r t h e f o l l o w i n g r e a s o n s : p r e v i o u s l y , t h e r e h a d b e e n n o c o m p r e h e n s i v e s u r v e y o f g r o u n d w a t e r q u a l i t y t ha t i n c l u d e d a l l a r e a s o f t h e v a l l e y ; t h e v a l l e y e n c o m p a s s e s s e v e r a l d i f f e r e n t l a n d u s e s , a n u m b e r o f w h i c h h a v e t he p o t e n t i a l t o n e g a t i v e l y i m p a c t g r o u n d w a t e r q u a l i t y , a n d f i n a l l y , t h e r e g i o n a l d i s t r i c t a n d l o c a l c o m m u n i t y w e r e i n t e r e s t e d i n h a v i n g r e s e a r c h o f t h i s n a t u r e u n d e r t a k e n . T h e w a t e r s h e d i s l o c a t e d a b o u t 7 5 k m e a s t o f t h e c i t y o f V a n c o u v e r o n t h e n o r t h s i d e o f t he F r a s e r R i v e r . T h i s p r e d o m i n a n t l y r u r a l w a t e r s h e d i s 8 3 7 0 h a ( 8 3 . 7 k m 2 ) i n s i z e a n d i n c l u d e s s t r e a m s tha t d r a i n s o u t h t h r o u g h H a t z i c L a k e i n t o t h e F r a s e r R i v e r . T h e l o c a t i o n o f t h e w a t e r s h e d r e l a t i v e t o V a n c o u v e r a n d t h e F r a s e r R i v e r i s s h o w n i n f i g u r e 1. A s t he f o c u s o f t h i s p r o j e c t w a s o n g r o u n d w a t e r r e s o u r c e s w i t h i n t h e w a t e r s h e d , t he field r e s e a r c h f o r t h i s p r o j e c t w a s c o n f i n e d t o t h e c e n t r a l l o w l a n d a r e a o f t h e w a t e r s h e d k n o w n as t h e H a t z i c V a l l e y . T h e r e a r e t h r e e d i s t i n c t g r o u n d w a t e r a q u i f e r s w i t h i n t h e H a t z i c w a t e r s h e d l o c a t e d i n t h i s l o w l a n d a r e a . T h e e a s t e r n a n d w e s t e r n a q u i f e r b o u n d a r i e s c o r r e s p o n d t o t h e e d g e o f t h e v a l l e y w h e r e t h e m o u n t a i n s r i s e s t e e p l y f r o m t h e v a l l e y f l o o r . T h e a r e a o f t h e l o w l a n d tha t e n c o m p a s s e s t h e a q u i f e r s c o n s i d e r e d i n t h e s t u d y i s a p p r o x i m a t e l y 3 1 0 0 h a (31 k m 2 ) . F i g u r e 1. L o c a t i o n o f t h e H a t z i c W a t e r s h e d 17 T h e f o l l o w i n g s e c t i o n s w i l l g i v e a n o v e r v i e w o f t he l a n d u s e i n t h e v a l l e y , a s w e l l a s d e t a i l e d d e s c r i p t i o n s o f t he g e o l o g y a n d g e o g r a p h y o f t h e l a n d o v e r l y i n g e a c h a q u i f e r . T h e a q u i f e r d e s c r i p t i o n s w i l l a l s o i n c l u d e a n y p r e v i o u s l y c o l l e c t e d i n f o r m a t i o n a b o u t t h e w a t e r q u a l i t y i n t h e s e a r e a s . 2.2 Land Use in the Watershed T h e l a n d i n t he s t u d y a r e a c a n b e s p l i t i n t o t h r e e p r e d o m i n a n t c a t e g o r i e s : a g r i c u l t u r a l , r e s i d e n t i a l a n d f o r e s t e d . T h e l a n d u s e s a r e n o t e v e n l y d i s t r i b u t e d t h r o u g h o u t t h e v a l l e y . A g r i c u l t u r e d o m i n a t e s t h e c e n t r a l a n d s o u t h e a s t e r n p o r t i o n o f t h e v a l l e y , w h e r e a s t h e n o r t h i s l a r g e l y c o v e r e d w i t h f o r e s t . D e n s e r e s i d e n t i a l a r e a s a r e f o u n d i n t h r e e s m a l l s u b d i v i s i o n s o n H a t z i c P r a i r i e ( t h e c e n t r a l v a l l e y ) a n d i n s e v e r a l s u b d i v i s i o n s a n d t r a i l e r p a r k s o n H a t z i c I s l a n d . H a t z i c I s l a n d i s a p o p u l a r r e c r e a t i o n a l a r e a a n d t h e r e a r e n u m e r o u s c a m p s a n d t r a i l e r p a r k s t h a t i n c r e a s e t h e p o p u l a t i o n s e a s o n a l l y . T h e u p l a n d s t o t h e e a s t a n d w e s t a r e l a r g e l y f o r e s t c o v e r e d a n d u n i n h a b i t e d d u e t o t h e s t e e p n e s s o f t h e s l o p e s . T a b l e 3 o u t l i n e s t h e a r e a a n d p e r c e n t a g e o f e a c h l a n d u s e f o r t h e l o w l a n d a r e a ( n o t t h e e n t i r e w a t e r s h e d ) . F i g u r e 2 s h o w s t h e c o m p l e t e l a n d u s e m a p f o r t h e v a l l e y . Table 3. Hatzic Valley Land Use Land use Total (area Ha) % Agriculture 1111.003 38.81 Forest 1047.422 36.59 Urban 20.552 0.72 Rural Residential 363.124 12.68 Other3 286.937 10.02 Total 2862.897 100.00 a = Other includes (water, road, wetland/non-forested riparian, greenhouse) 1 8 Figure 2 . Land Use in the Hatzic Valley 19 2.3 Drinking Water Sources R e s i d e n t s o f t h e H a t z i c V a l l e y u s e b o t h g r o u n d w a t e r a n d s u r f a c e w a t e r s o u r c e s f o r d o m e s t i c c o n s u m p t i o n . A s t h e f o c u s o f t h i s p r o j e c t i s o n t h e g r o u n d w a t e r s o u r c e s , t h e s e w i l l b e d e s c r i b e d i n d e t a i l i n s u b s e q u e n t a n a l y s i s . T h e s u r f a c e w a t e r s o u r c e s u s e d f o r d r i n k i n g a r e m a i n l y s m a l l s t r e a m s t ha t r u n o f f t h e m o u n t a i n s . A l t h o u g h m o s t r e s i d e n t s r e l y o n p r i v a t e , i n d i v i d u a l , w a t e r s u p p l i e s t o m e e t t h e i r d o m e s t i c n e e d s t h e r e a r e a f e w s m a l l c o m m u n i t y w a t e r s y s t e m s ( w h i c h s e r v e m o r e t h a n 2 h o u s e h o l d s ) w i t h i n t h e s t u d y a r e a . T h e t h r e e s u b d i v i s i o n s i n t h e c e n t r a l v a l l e y ( H a t z i c P r a i r i e ) a r e s u p p l i e d s u r f a c e w a t e r b y c o m m u n i t y w a t e r s y s t e m s . A t l e a s t o n e o f t h e s e c o m m u n i t i e s ( a l o n g S w a r d R o a d j u s t n o r t h o f H a t z i c L a k e ) i s o n a p e r m a n e n t b o i l w a t e r o r d e r a c c o r d i n g t o a l a r g e s i g n at t h e e n t r a n c e t o t h e a r e a . I n f o r m a t i o n a b o u t t h e s e w a t e r s y s t e m s w a s n o t e a s y t o o b t a i n ( C h a p m a n , p e r s c o m . 2 0 0 2 ) a n d t a p w a t e r f r o m t h e s e r e s i d e n t s w a s n o t c o l l e c t e d a s p a r t o f t h i s p r o j e c t . It i s n o t k n o w n i f t h i s b o i l w a t e r o r d e r w a s i s s u e d a s a r e s u l t o f a s p e c i f i c c o n t a m i n a t i o n e v e n t o r a s a p r e c a u t i o n a r y m e a s u r e b e c a u s e t h e w a t e r i s n o t t r e a t e d . T h e l a t t e r i s t h e l i k e l y s c e n a r i o ; H a t z i c i s n o t i n c l u d e d i n t h e l i s t o f 2 8 w a t e r b o r n e d i s e a s e o u t b r e a k s t ha t h a v e o c c u r r e d i n B C s i n c e 1 9 8 0 ( C h r i s t e n s e n a n d P a r f i t t , 2 0 0 3 ) . T h e r e i s o n e c o m m u n i t y w a t e r s h e d i n t h e v a l l e y . T h e K e n w o r t h y C r e e k C o m m u n i t y w a t e r s h e d i s u s e d b y t h e H a t z i c P r a i r i e W a t e r U s e r ' s C o m m u n i t y ( W U C ) f o r d o m e s t i c c o n s u m p t i o n . T h i s W U C h o l d s 1 0 d o m e s t i c w a t e r l i c e n s e s t ha t u s e K e n w o r t h y C r e e k a s a s o u r c e ( C a m e r o n , 1 9 9 8 ) . It i s n o t k n o w n i f a n y o f t h e s e l i c e n c e s s u p p l y t h e s u b d i v i s i o n s m e n t i o n e d a b o v e h o w e v e r t h e p r o x i m i t y o f K e n w o r t h y c r e e k t o t h e s u b d i v i s i o n a l o n g S w a r d r o a d s u g g e s t s t h i s m a y b e l i k e l y . 2.4 Aquifer Classification M a n y g r o u n d w a t e r a q u i f e r s i n B r i t i s h C o l u m b i a h a v e n o t b e e n e x t e n s i v e l y s t u d i e d . O n e o f t h e m o s t u s e f u l s o u r c e s o f i n f o r m a t i o n a b o u t a q u i f e r s i n t h e F r a s e r L o w l a n d i s a r e p o r t p u b l i s h e d b y t h e B C m i n i s t r y o f E n v i r o n m e n t , L a n d s a n d P a r k s ( n o w W a t e r , L a n d a n d A i r P r o t e c t i o n ) i n 1 9 9 4 e n t i t l e d , " A P r o p o s e d C l a s s i f i c a t i o n S y s t e m f o r G r o u n d w a t e r M a n a g e m e n t i n B r i t i s h C o l u m b i a " ( K r e y e a n d W e i , 1 9 9 4 ) . T h e a q u i f e r c l a s s i f i c a t i o n s y s t e m w a s c r e a t e d t o h e l p w i t h p r i o r i t i z i n g m a p p i n g , a s s e s s m e n t , a n d m o n i t o r i n g o f a q u i f e r s , t o p r o v i d e m o r e s y s t e m a t i c c o m p a r i s o n o f d i f f e r e n t a q u i f e r s , a n d as a n i n f o r m a t i o n t o o l t o i n c r e a s e a w a r e n e s s o f g r o u n d w a t e r r e s o u r c e s . T h e c l a s s i f i c a t i o n s y s t e m c o n s i s t s o f t w o p a r t s . T h e f i r s t i s t h e c l a s s i f i c a t i o n c o m p o n e n t w h i c h c a t e g o r i z e s a q u i f e r s b a s e d o n t h e i r c u r r e n t l e v e l o f d e v e l o p m e n t a n d v u l n e r a b i l i t y t o c o n t a m i n a t i o n , a n d t h e s e c o n d i s a r a n k i n g c o m p o n e n t t o i n d i c a t e t h e r e l a t i v e o v e r a l l p r i o r i t y f o r m a p p i n g a n d m a n a g e m e n t o f t h e a q u i f e r b a s e d o n a n u m b e r o f p h y s i c a l a n d w a t e r u s e c r i t e r i a . T h e c l a s s i f i c a t i o n c o m p o n e n t i s f u r t h e r d i v i d e d i n t o 2 s u b - s e c t i o n s , t h e first b e i n g a d e v e l o p m e n t 20 s u b - c l a s s a n d t h e s e c o n d a v u l n e r a b i l i t y s u b - c l a s s . T h e d e v e l o p m e n t s u b - c l a s s i s b a s e d o n t h e l e v e l o f g r o u n d w a t e r u s e i n r e l a t i o n t o t h e a q u i f e r y i e l d o r p r o d u c t i v i t y . T h e c l a s s e s f o r d e v e l o p m e n t a r e a s f o l l o w s ; h e a v y ( I ) , m o d e r a t e ( I I ) o r l i g h t ( I I I ) . T h e v u l n e r a b i l i t y s u b - c l a s s a s s e s s e s t h e v u l n e r a b i l i t y o f e a c h a q u i f e r t o c o n t a m i n a t i o n from s u r f a c e s o u r c e s , a n d i s b a s e d o n t h e t y p e , t h i c k n e s s , a n d e x t e n t o f t h e g e o l o g i c a l m a t e r i a l o v e r l y i n g t h e a q u i f e r , t h e d e p t h t o w a t e r ( o r t o p o f c o n f i n i n g l a y e r ) , a n d t h e p o r o s i t y o f t h e a q u i f e r m a t e r i a l s . T h e v u l n e r a b i l i t y r a n k i n g s a r e h i g h ( A ) , m o d e r a t e ( B ) o r l o w ( C ) . T h e c o m b i n a t i o n o f d e v e l o p m e n t r a n k i n g a n d v u l n e r a b i l i t y r a n k i n g r e s u l t s i n a q u i f e r c l a s s ( o f w h i c h t h e r e a r e n i n e p o s s i b l e c o m b i n a t i o n s ) . T h e r a n k i n g f o r e a c h a q u i f e r i s a n u m e r i c a l m e a s u r e m e n t o f t h e p r i o r i t y f o r m a p p i n g a n d a s s e s s m e n t . T h e p o s s i b l e r a n k s r a n g e from 5 t o 2 1 , w h e r e h i g h e r - r a n k i n g v a l u e s a r e a n i n d i c a t i o n o f h i g h e r r e l a t i v e p r i o r i t y . T h e r a n k i n g s a r e b a s e d o n t h e f o l l o w i n g c r i t e r i a : p r o d u c t i v i t y , v u l n e r a b i l i t y , s i z e , d e m a n d , t y p e o f u s e , q u a l i t y c o n c e r n s , a n d q u a n t i t y c o n c e r n s . S e e K r e y e a n d W e i ( 1 9 9 4 ) f o r a m o r e c o m p l e t e d e s c r i p t i o n o f t h e m e t h o d o f c l a s s i f y i n g a n d r a n k i n g t h e a q u i f e r s . Figure 3. Watershed and Aquifer Boundaries and Areas, Hatzic, British Columbia T h e i d e n t i f i c a t i o n o f t h e t h r e e d i s t i n c t a q u i f e r s w i t h i n t h e H a t z i c W a t e r s h e d c o m e s from t h e i n i t i a l r e p o r t o n A q u i f e r C l a s s i f i c a t i o n i n B C , w h i c h u s e d t h e F r a s e r L o w l a n d a s t h e p i l o t s t u d y a r e a . T h e p u r p o s e o f t h e a q u i f e r d e l i n e a t i o n w a s o n l y t o r a n k , c l a s s i f y , a n d i n v e n t o r y t h e a q u i f e r s . D e t a i l e d a n a l y s i s o f f l o w s y s t e m s a n d v a r i a t i o n s i n w a t e r q u a l i t y w e r e b e y o n d t h e s c o p e 2 1 o f t ha t p r o j e c t . T h e a q u i f e r s w e r e d e l i n e a t e d b a s e d o n p r e v i o u s l y e x i s t i n g i n f o r m a t i o n o n s u r f i c i a l g e o l o g y f o r s h a l l o w a q u i f e r s a n d H a l s t e a d ' s h y d r o - s t a t i g r a p h i c u n i t s ( H a l s t e a d , 1 9 8 6 ) f o r d e e p e r c o n f i n e d a q u i f e r s . I n f o r m a t i o n f r o m a v a i l a b l e c o n s u l t a n t s r e p o r t s , o t h e r p u b l i s h e d a n d u n p u b l i s h e d r e p o r t s , a n d w e l l r e c o r d s w e r e a l s o u s e d . A s p r e v i o u s l y m e n t i o n e d , t h r e e s e p a r a t e a q u i f e r s w i t h i n t h e H a t z i c W a t e r s h e d h a v e b e e n d e l i n e a t e d ( s e e f i g u r e 3 ) . T w o o f t h e s e a q u i f e r s a r e r a n k e d a s I I I A w i t h r a n k i n g s o f 1 2 a n d 1 0 , t ha t i s , t h e y a r e n o t h i g h l y d e v e l o p e d b u t a r e h i g h l y v u l n e r a b l e t o c o n t a m i n a t i o n . T h e t h i r d a q u i f e r i s r a n k e d as I I I C m e a n i n g i t i s n o t h i g h l y d e v e l o p e d o r v u l n e r a b l e t o c o n t a m i n a t i o n . T h e s e a q u i f e r s w i l l b e d e s c r i b e d i n d e t a i l i n t he f o l l o w i n g t h r e e s e c t i o n s . 2.4.1 Nicomen Slough Aquifer T h e s o u t h e r n m o s t a q u i f e r w i t h i n t h e H a t z i c W a t e r s h e d i s t h e N i c o m e n S l o u g h a q u i f e r ( h e r e a f t e r k n o w n a s A Q 1 ) . T h i s a q u i f e r h a s a n a r e a o f a p p r o x i m a t e l y 6 0 k m 2 a n d e x t e n d s t o t h e eas t s e v e r a l k i l o m e t e r s o u t s i d e t h e s t u d y a r e a . O n l y t h e a r e a w i t h i n t h e H a t z i c W a t e r s h e d ( l e s s t h a n 1 0 k m 2 ) , w h i c h i n c l u d e s H a t z i c I s l a n d a n d t he l a n d d i r e c t l y eas t o f i t ( w h i c h i s b o u n d e d b y S y l v e s t e r R o a d o n t h e e a s t a n d L o u g h e e d H i g h w a y t o t h e s o u t h ) , w e r e m o n i t o r e d as p a r t o f t h i s s t u d y ( s e e F i g u r e 3 a n d F i g u r e 4 ) . A Q 1 i s a s h a l l o w , u n c o n f i n e d , s a n d a q u i f e r ; t h e d e p t h t o t h e t o p o f t h e a q u i f e r i s e s t i m a t e d t o b e l e s s t h a n 1 0 m ( i n s o m e c a s e s a s l i t t l e as 3 m ) ( C a r m i c h a e l et al., 1 9 9 5 ; K r e y e a n d W e i , 1 9 9 4 ) . T h i s a q u i f e r w a s g i v e n a c l a s s i f i c a t i o n o f I I I A m e a n i n g i t i s h i g h l y v u l n e r a b l e t o c o n t a m i n a t i o n b u t n o t h e a v i l y u s e d . A l o c a l e x c e p t i o n i s o n H a t z i c I s l a n d w h e r e g r o u n d w a t e r u s e i s h i g h ( C a r m i c h a e l et al, 1 9 9 5 ) . T h i s m e a n s t ha t t h e a q u i f e r c l a s s i f i c a t i o n f o r t h e e n t i r e N i c o m e n S l o u g h a q u i f e r i s n o t a c c u r a t e o n H a t z i c I s l a n d a n d t ha t t he v u l n e r a b i l i t y t o c o n t a m i n a t i o n i n t h i s a r e a i s h i g h . T h e r a n k i n g o f t he a q u i f e r i s 12 o n a s c a l e o f 5 t o 2 1 , m e a n i n g i t w o u l d h a v e i n t e r m e d i a t e p r i o r i t y f o r m a p p i n g a n d a s s e s s m e n t f r o m t h e p r o v i n c i a l g o v e r n m e n t . T h e o n l y w a t e r q u a l i t y c o n c e r n f o r t h i s a q u i f e r i d e n t i f i e d b y K r e y e a n d W e i ( 1 9 9 4 ) w a s l o c a l l y h i g h i r o n l e v e l s ( a n o n - h e a l t h r e l a t e d p r o b l e m ) . T h e r e a r e s e v e r a l w e l l l o g s a v a i l a b l e f o r w e l l s i n t h i s a r e a ; h o w e v e r , n o n e o f t h e w e l l l o g s h a v e s t r a t i g r a p h i c i n f o r m a t i o n s o p r o f i l e s c o u l d n o t b e c r e a t e d . 2 2 Figure 4. AQ1 - Nicomen Slough Aquifer Hatzic Island and the region directly east of it have the same surficial geology; the entire area is classified as Fraser River Sediments. In this area these are channelled deposits (expressed at the surface by ridges and swales) up to 10m thick, consisting of sandy loam and loamy sand that overlie estuarine fine sand to clayey silt (Armstrong, 1980). Soils on the island are moderately well to well drained, and generally medium to moderately coarse in texture. The soils just east of the island are not as uniform as on the island and in this area, in addition to soils similar to those found on the island, there are areas where the drainage is imperfect due to a fluctuating groundwater table. The soils in these areas tend to be medium to moderately fine textured (Luttmerding, 1980a). AQ1 is one of the only regions in the study area where any previously collected water quality information is available. Eight community wells on Hatzic Island were sampled in 1992-1993 as part of the Fraser Valley Groundwater Monitoring Program (Carmichael et al, 1995). Nitrate values for the wells sampled as part of this report were not above health standards and ranged from 0.06 mg/L to 5.79 mg/L. These wells had depths ranging from 24.38 to 6.1 m. The water table, however, was reported to be as little as 3 m from the surface for two of these wells including the 24.38 m deep well. Water quality information was collected for Hatzic Lake in the 23 1 9 7 0 ' s ( D r i n n a n , 1 9 7 5 ) . A t tha t t i m e , w a t e r q u a l i t y i n t h e l a k e w a s r e p o r t e d t o b e b e l o w s t a n d a r d s f o r m o s t p a r a m e t e r s , b u t e u t r o p h i c a t i o n w a s a c o n c e r n . A t t h e t i m e , r e c o m m e n d a t i o n s w e r e m a d e t ha t " i n v e s t i g a t i o n s s h o u l d i n c l u d e r e v i e w s o n t h e i m p r o v e m e n t o f f a u l t y s e p t i c t a n k s , f e a s i b i l i t y o f w a s t e c o l l e c t i o n a n d t r e a t m e n t . . . d u e to p o o r s o i l d r a i n a g e a n d t h e p o s s i b i l i t y o f p o t e n t i a l h e a l t h p r o b l e m s , t h e a r e a m a y r e q u i r e a s e w e r s y s t e m i f t h e r e i s a n i n c r e a s e i n p o p u l a t i o n , " ( D r i n n a n , 1 9 7 5 ) ( n o t e t ha t L u t t m e r d i n g ' s s o i l m a p s ( 1 9 8 0 a ) r e p o r t e d t h e s o i l s o n t h e i s l a n d as w e l l t o m o d e r a t e l y w e l l d r a i n e d w h e r e a s t h i s r e p o r t ( w r i t t e n b e f o r e 1 9 8 0 ) s a y s t h e s o i l i s p o o r l y d r a i n e d ) . H a t z i c L a k e i s t h e m o s t d i s t i n c t i v e g e o g r a p h i c a l f e a t u r e i n t h e a r e a . T h i s h o r s e s h o e s h a p e d l a k e ( l i k e l y a f o r m e r m e a n d e r o f t h e F r a s e r R i v e r ) i s q u i t e s h a l l o w , w i t h a m e a n d e p t h o f o n l y 2 m a n d a n a r e a o f a b o u t 3 0 0 h a . T h e w a t e r l e v e l f l u c t u a t e s g r e a t l y w i t h t h e s e a s o n . I n f a c t m u c h o f t h e e a s t e r n p o r t i o n o f t h e l a k e r o u t i n e l y d r i e s u p i n t h e s u m m e r e x p o s i n g v a s t m u d f l a t s t h r o u g h w h i c h o n l y a n a r r o w c h a n n e l c o n t i n u e s t o r u n . H a t z i c I s l a n d , a p e n i n s u l a r u n n i n g u p t h e c e n t e r o f t he l a k e ( s e e f i g 4 ) , i s t h e m o s t d e n s e l y p o p u l a t e d a r e a o f t h e v a l l e y . T h e r e i s n o s u r f a c e w a t e r o n t h e i s l a n d a n d , t h e r e f o r e , t h e r e s i d e n t s a r e e n t i r e l y d e p e n d e n t o n g r o u n d w a t e r f o r t h e i r d o m e s t i c n e e d s . T h e l a k e a n d t h e i s l a n d a r e a p o p u l a r r e c r e a t i o n a l a r e a w i t h a m i x t u r e o f s e a s o n a l a n d p e r m a n e n t d w e l l i n g s i n t r a i l e r p a r k s , s u b d i v i s i o n s , a n d o n l a r g e r r u r a l l o t s . S o m e a g r i c u l t u r e i s a l s o p r e s e n t o n t h e i s l a n d , b u t i t i s n o t a d o m i n a n t l a n d u s e , as i t i s o n t h e a r e a j u s t eas t o f t h e i s l a n d . T a b l e 4 o u t l i n e s t h e l a n d u s e f o r A Q 1 i n h a a n d a s p e r c e n t a g e s o f t h e t o t a l a r e a c o n s i d e r e d i n t h e s t u d y . Table 4. Land Use AQ1 Land use AQ1 (area ha) % Agriculture 410.673 59.39 Forest 42.225 6.11 Urban 30.307 4.38 Rural Residential 75.545 10.92 Other" 133.774 19.34 Total 691.524 100.00 a = Other includes (water, road, wetland/non-forested riparian, greenhouse) 2A.2 Hatzic Prairie Aquifer T h e s e c o n d a q u i f e r w i t h i n t h e s t u d y a r e a i s t h e H a t z i c P r a i r i e A q u i f e r ( h e r e a f t e r k n o w n as A Q 2 ) . T h i s a q u i f e r i s o v e r l a i n b y t h e H a t z i c P r a i r i e , a f l a t a r e a t ha t e x t e n d s n o r t h f r o m H a t z i c l a k e a n d i s b o u n d e d o n t h e e a s t a n d w e s t b y t h e h i l l s w h i c h r i s e s t e e p l y f r o m t h e v a l l e y f l o o r . T h e e a s t e r n b o u n d a r y i s a l s o d e f i n e d b y S y l v e s t e r R o a d . T h e n o r t h e r n b o u n d a r y f o r t h i s a r e a i s j u s t p a s t 2 4 D u r i e u R o a d , w h e r e t h e t o p o g r a p h y b e g i n s t o r i s e . T h e r e a re m a n y s t r e a m s t ha t c r o s s t h i s p a r t o f t h e w a t e r s h e d , i n c l u d i n g H a t z i c S l o u g h , L e g a c e a n d P a t t i s o n c r e e k s , a l l o f w h i c h e v e n t u a l l y d r a i n i n t o H a t z i c L a k e . T h e l a n d i s v e r y f l a t a n d t he d o m i n a n t l a n d u s e i s a g r i c u l t u r e ( 6 9 % ) ( s e e t a b l e 5 f o r c o m p l e t e l a n d u s e i n h a a n d as p e r c e n t a g e s o f t he t o t a l ) . T h e t h r e e r u r a l s u b d i v i s i o n s m e n t i o n e d p r e v i o u s l y tha t u s e s u r f a c e w a t e r f o r t h e i r d o m e s t i c n e e d s a r e l o c a t e d o n t h e p r a i r i e . A s i d e f r o m t h e s e s u b d i v i s i o n s , H a t z i c P r a i r i e i s n o t d e n s e l y p o p u l a t e d . T h e h i g h w a t e r t a b l e a n d f r e q u e n c y o f f l o o d i n g m a y b e c o n t r i b u t i n g f a c t o r s . Ihouse.shp O Wel ls S a m p l e d I I A Q 2 • R o a d s A / \ / S t reams « C o n t o u r (North) A / 1 0 0 M - C O N T O U R S 2 0 M - C O N T O U R S C o n t o u r (South) /\y 1 0 0 M - C O N T O U R S 2 0 M - C O N T O U R S L a k e 500 1000 Meters Figure 5. AQ2 - Hatzic Prair ie Aqui fer A Q 2 w a s a l s o g i v e n a c l a s s i f i c a t i o n I I I A , m e a n i n g t ha t i t i s h i g h l y v u l n e r a b l e t o c o n t a m i n a t i o n b u t i s n o t h e a v i l y u s e d ; a g a i n t he o n l y w a t e r q u a l i t y c o n c e r n i d e n t i f i e d b y K r e y e a n d W e i ( 1 9 9 4 ) w a s n o n - h e a l t h r e l a t e d l o c a l i z e d i r o n p r o b l e m s . T h i s a q u i f e r i s a l s o s h a l l o w a n d u n c o n f i n e d w i t h t h e p r e d o m i n a n t m a t e r i a l o f t he a q u i f e r b e i n g s a n d a n d g r a v e l . T h e d e p t h t o t he t o p o f t h e a q u i f e r i s e s t i m a t e d t o b e l e s s t h a n 10 m . B e c a u s e o f h i g h l e v e l s o f i r o n a n d t h e p r o x i m i t y t o s t r e a m s e m e r g i n g f r o m t h e h e a d w a t e r s m a n y r e s i d e n t s o p t t o u s e s u r f a c e w a t e r f o r d r i n k i n g i n t h i s p a r t o f t h e v a l l e y . T h e w e l l s s a m p l e d f o r t h i s p r o j e c t w e r e c o n c e n t r a t e d t o w a r d s t h e n o r t h o f t h e a q u i f e r . T h e s u r f i c i a l g e o l o g y o n t h e H a t z i c P r a i r i e i s t h e m o s t v a r i e d o f t he t h r e e a q u i f e r s w i t h i n t h e s t u d y a r e a . T h e e n t i r e a r e a i s u n d e r l a i n b y F r a s e r R i v e r s e d i m e n t s o f t h e t y p e f o u n d o v e r a l l o f 25 A Q 1 . I n s o m e a r e a s t h e s e s e d i m e n t s a r e a t t h e s u r f a c e , b u t o v e r a m a j o r i t y o f t h e p r a i r i e t h e d o m i n a n t m a t e r i a l at t h e s u r f a c e a r e S a l i s h S e d i m e n t s . S o m e o f t h e s e i n c l u d e p e a t , o r g a n i c s i l t l o a m a n d s i l t y c l a y l o a m ( 0 . 3 t o 10 m t h i c k ) b u t t h e m a j o r i t y a r e s t r e a m d e p o s i t s c l a s s i f i e d a s l o w l a n d s t r e a m c h a n n e l f i l l a n d o v e r b a n k s a n d y l o a m a n d c l a y l o a m , w h i c h i n p l a c e s c o n t a i n s d i s s e m i n a t e d o r g a n i c m a t e r i a l u p to 8 m t h i c k . T h e r e t w o a r e a s , o n e t o w a r d s t h e n o r t h o f t h e a q u i f e r a n d t h e o t h e r o n t h e c e n t r a l w e s t e r n s i d e o f t h e v a l l e y , w h e r e t h e r e a r e s l o p e d e p o s i t s c o n s i s t i n g o f f a n a n d l a n d s l i d e g r a v e l , as w e l l as s a n d a n d r u b b l e , u p to 1 5 + m t h i c k . T h e s e d e p o s i t s a l s o o v e r l i e F r a s e r R i v e r S e d i m e n t s . T h e r e a r e a v a r i e t y o f d i f f e r e n t s o i l t y p e s o n t h e H a t z i c P r a i r i e , w h i c h r a n g e i n t e x t u r e f r o m f i n e t o m e d i u m t e x t u r e d t o p a r t i a l l y d e c o m p o s e d o r g a n i c m a t t e r . M o s t o f t h e s o i l s a r e p o o r l y d r a i n e d d u e to a h i g h g r o u n d w a t e r t a b l e . T h e r e a r e s o m e l o c a l i z e d a r e a s o f c o a r s e a l l u v i a l f a n d e p o s i t s t ha t a r e w e l l t o r a p i d l y d r a i n e d ( L u t t m e r d i n g , 1 9 8 0 a ) . T h i s s o i l i s f o u n d i n t w o l o c a t i o n s a n d i s a s s o c i a t e d w i t h t h e s l o p e d e p o s i t s m e n t i o n e d i n t h e s u r f i c i a l g e o l o g y d e s c r i p t i o n . Table 5. Land Use AQ2 Land use AQ2 (area ha) % Agriculture 617.271 62.79 Forest 126.032 12.82 Urban 21.931 2.23 Rural Residential 103.275 10.50 Other" 114.641 11.66 Total 983.15 100.00 a = Other includes (water, road, wetland/non-forested riparian, greenhouse) 2.4.3 Miracle Valley Aquifer T h e t h i r d a q u i f e r w i t h i n t h e s t u d y a r e a i d e n t i f i e d , b y K r e y e a n d W e i ( 1 9 9 4 ) i s t h e M i r a c l e V a l l e y a q u i f e r ( h e r e a f t e r k n o w n as A Q 3 ) . T h i s a q u i f e r i s a l a r g e l y s a n d a n d g r a v e l a q u i f e r c l a s s i f i e d as I I I C , m e a n i n g t ha t i t i s n e i t h e r h e a v i l y u s e d n o r h i g h l y v u l n e r a b l e t o c o n t a m i n a t i o n . I n c o n t r a s t t o t h e f i r s t t w o a q u i f e r s , A Q 3 i s a c o n f i n e d a q u i f e r w i t h n o i d e n t i f i e d w a t e r q u a l i t y p r o b l e m s . T h e t o p o f t h i s d e e p e r a q u i f e r i s e s t i m a t e d at 3 5 t o 5 0 m d e e p . T h i s a q u i f e r i s l o c a t e d a t t h e n o r t h e n d o f t h e H a t z i c V a l l e y w h e r e the . t o p o g r a p h y r i s e s u p t o t h e a r e a k n o w n a s t h e M i r a c l e V a l l e y . T h e h u m a n p o p u l a t i o n i s d e n s e r i n t h i s a r e a t h a n o n H a t z i c p r a i r i e , b u t n o t a s d e n s e as o n H a t z i c I s l a n d . T h e r e a r e n o s u b d i v i s i o n s i n t h i s a r e a . M o s t o f t h e l a n d i s c o v e r e d i n f o r e s t a n d t h e m a j o r i t y o f p e o p l e l i v e o n l a r g e t r e e d l o t s ( s e e t a b l e 6 f o r c o m p l e t e a r e a o f e a c h l a n d u s e o n t h i s a q u i f e r ) . D r i n k i n g w a t e r i s m a i n l y f r o m g r o u n d w a t e r s o u r c e s b u t s o m e s u r f a c e w a t e r i s u s e d f o r d o m e s t i c p u r p o s e s as w e l l . S o m e o f t h e w e l l s s a m p l e d i n t h e M i r a c l e V a l l e y a r e n o t l o c a t e d i n 2 6 t h e H a t z i c w a t e r s h e d b u t a r e p a r t o f t he C a s c a d e C r e e k s y s t e m , w h i c h d r a i n s n o r t h i n t o S t a v e L a k e , r a t h e r t h a n s o u t h i n t o H a t z i c L a k e . T h e s u r f i c i a l g e o l o g y o f t h e M i r a c l e V a l l e y i s m i x e d a n d c o n s i s t s o f m o r e t h a n o n e s t r a t i g r a p h i c u n i t . T h e p r i m a r y u n i t i s t h e F o r t L a n g l e y F o r m a t i o n , a g l a c i o m a r i n e s t o n y s i l t t o l o a m y c l a y tha t c a n b e 8 t o 1 0 0 m t h i c k . O v e r l y i n g m u c h o f t he F o r t L a n g l e y f o r m a t i o n i s a l a y e r o f s a n d y t i l l a n d s u b - s t r a t i f i e d d r i f t 0 . 5 - 2 m t h i c k ( A r m s t r o n g , 1 9 8 0 ) . T h e r e a r e s e v e r a l d i f f e r e n t s o i l s i n t h e M i r a c l e V a l l e y . T h e p r e d o m i n a n t s o i l i s a m o d e r a t e l y w e l l d r a i n e d m e d i u m t o m o d e r a t e l y f i n e t e x t u r e d g l a c i o m a r i n e d e p o s i t . T h e r e a r e l o c a l a r e a s w h e r e 4 0 t o 1 6 0 c m o f w e l l - d e c o m p o s e d o r g a n i c m a t e r i a l i s u n d e r l a i n b y m o d e r a t e l y fine t e x t u r e d g l a c o m a r i n e d e p o s i t s w i t h v e r y p o o r d r a i n a g e d u e t o a p e r c h e d w a t e r t a b l e . I n o t h e r a r e a s t he s o i l s a r e w e l l d r a i n e d g r a v e l y o u t w a s h d e p o s i t s . F i n a l l y t h e r e a r e a l s o a r e a s a l o n g t h e eas t o f t h e v a l l e y w h e r e t h e r e a r e c o a r s e - t e x t u r e d a l l u v i a l f a n d e p o s i t s w i t h w e l l t o r a p i d d r a i n a g e ( L u t t r n e r d i n g , 1 9 8 0 a & b ) . MacNab Creek j J y y y • Houses HPLY • Wells Sampled ratt Road mm . r r*> / \ / Streams Contour / \ / 100M-CONTOURS 20M-CON TOURS 1000 Meters F i g u r e 6 . A Q 3 - M i r a c l e V a l l e y A q u i f e r 27 T h e m o s t d e t a i l e d g r o u n d w a t e r i n v e s t i g a t i o n s i n t h e s t u d y a r e a h a v e t a k e n p l a c e i n t h e M i r a c l e V a l l e y a r e a . L o c a l r e s i d e n t s h a v e b e e n c o n c e r n e d a b o u t p o s s i b l e i m p a c t s o n t h e i r g r o u n d w a t e r q u a l i t y a n d q u a n t i t y f r o m b l a s t i n g at a r o c k q u a r r y i n t he n o r t h e a s t o f t h e a r e a ( n e a r t h e c o r n e r o f S t a v e L a k e R o a d a n d H a r t l e y R o a d ) . R e p o r t s w r i t t e n b y i n d e p e n d e n t c o n s u l t a n t s h a v e b e e n c o m m i s s i o n e d , b o t h b y t h e q u a r r y o w n e r s , as w e l l as b y a g r o u p o f c o n c e r n e d l o c a l r e s i d e n t s , t o e v a l u a t e t h e p o s s i b l e i m p a c t o n g r o u n d w a t e r r e s o u r c e s o f t h i s q u a r r y . T h e s e r e p o r t s h a v e c o n t r i b u t e d t o t h e k n o w l e d g e o f t h e l o c a l g r o u n d w a t e r r e g i m e b y c o n s o l i d a t i n g k n o w n i n f o r m a t i o n a b o u t w e l l s i n t he a r e a . R e s i d e n t s , c o o r d i n a t e d b y m e m b e r s o f t h e l o c a l r a t e p a y e r s a s s o c i a t i o n , h a v e g o n e d o o r - t o - d o o r c o l l e c t i n g i n f o r m a t i o n a b o u t w e l l d e p t h s a n d l o c a t i o n s a n d , w h e r e p o s s i b l e , t h e w e l l l o g s f o r e a c h w e l l w i t h i n a 1.5 k m r a d i u s o f t h e q u a r r y . T h e s e r e p o r t s c o n t a i n i n f o r m a t i o n a b o u t t h e g r o u n d w a t e r i n t h e M i r a c l e V a l l e y at a f i n e r s c a l e t h a n t h a t u s e d b y K r e y e a n d W e i i n 1 9 9 4 . T h e c o n s u l t a n t s ' r e p o r t s , w r i t t e n i n r e s p o n s e t o t h e q u a r r y h a v e i d e n t i f i e d l o c a l i z e d " s u b " a q u i f e r r e g i m e s a n d m a d e e d u c a t e d g u e s s e s a b o u t f l o w d i r e c t i o n a n d r e c h a r g e a r e a s . T h e r e p o r t s m e n t i o n e d h e r e i n c l u d e o n e r e p o r t w r i t t e n b y A l a n D a k i n o f P i t e a u A s s o c i a t e s o f i n 1 9 9 4 f o r J o h n C o n r o y a n d N e i g h b o u r s , t h e c o n c e r n e d c i t i z e n s g r o u p . T h i s r e p o r t w a s w r i t t e n a t t he t i m e o f t he o r i g i n a l q u a r r y a p p l i c a t i o n . T h e o t h e r w a s w r i t t e n b y P a c i f i c H y d r o l o g y C o n s u l t a n t s L t d . i n 2 0 0 3 a s a n u p d a t e t o a r e p o r t b y t h e s a m e c o m p a n y i n 1 9 9 4 o f p o t e n t i a l i m p a c t s b y t h e q u a r r y o p e r a t i o n o n g r o u n d w a t e r q u a l i t y a n d q u a n t i t y . T h e f o r m e r r e p o r t w i l l b e r e f e r r e d t o a s " t h e D a k i n R e p o r t " a n d t h e l a t t e r as " P H C L 2 0 0 3 " . T h e s e r e p o r t s c o n f i r m e d t ha t t h e p r e d o m i n a n t s o u r c e o f g r o u n d w a t e r i n t h e a r e a i s t h e d e e p c o n f i n e d r e g i o n a l a q u i f e r ( A Q 3 ) b u t t ha t i n a d d i t i o n t o t h i s s o u r c e t h e r e a r e s e v e r a l s h a l l o w p e r c h e d a q u i f e r s i n t he a r e a ( t h i s i s c o n s i s t e n t w i t h L u t t m e r d i n g , ( 1 9 8 0 a ) ) . T h e s e p e r c h e d a q u i f e r s a r e e v i d e n t b y t he a b u n d a n t p o n d s o n t h e w e s t e r n e d g e o f t h e v a l l e y a n d " c o n s i s t o f s a n d y l e n s e s i n t h e c l a y u n i t t ha t c a n l i k e l y o n l y s u s t a i n a f e w l o w y i e l d i n g w e l l s " ( P i t e a u A s s o c i a t e s , 1 9 9 4 ) . M a n y l o w y i e l d i n g b e d r o c k u n i t s s c a t t e r e d a r o u n d t h e m a r g i n s o f t h e v a l l e y w e r e a l s o i d e n t i f i e d a s t h e p o s s i b l e s o u r c e o f s o m e g r o u n d w a t e r i n t h e r e g i o n . P H C L 2 0 0 3 c o m m e n t e d o n t h e p o s s i b l e f l o w d i r e c t i o n s f o r g r o u n d w a t e r i n t h e a r e a a n d c o n c l u d e d t ha t , a l t h o u g h m u c h o f t h e g r o u n d w a t e r f l o w s s o u t h t o w a r d s H a t z i c L a k e , t h e r e i s a g r o u n d w a t e r d i v i d e i n t h e v a l l e y a n d s o m e o f t h e g r o u n d w a t e r i n t h e a r e a f l o w s n o r t h t o w a r d s S t a v e L a k e . It i s n o t k n o w n i f t h i s d i v i d e c l o s e l y m i r r o r s t h e w a t e r s h e d d i v i d e tha t i s p r e s e n t t o w a r d s t h e n o r t h o f t h e M i r a c l e V a l l e y . T h e l o c a t i o n o f g r o u n d w a t e r r e c h a r g e a r e a s h a s b e e n a c o n c e r n o f l o c a l r e s i d e n t s w o r r i e d a b o u t l a n d u s e i m p a c t s o n t h e i r w a t e r q u a l i t y . S e v e r a l t h e o r i e s a b o u t t h e l o c a t i o n o f r e c h a r g e a r e a s 2 8 w e r e g i v e n i n t h e c o n s u l t a n t s ' r e p o r t s . I t w a s h y p o t h e s i z e d i n t h e D a k i n R e p o r t t ha t t h e a q u i f e r w a s p a r t l y r e c h a r g e d f r o m S t a v e L a k e a n d l i k e l y a l s o r e c h a r g e d f r o m s i d e c r e e k s . P H C L 2 0 0 3 t h o u g h t i t m o s t l i k e l y t ha t r e c h a r g e w a s l a r g e l y f r o m t h e s t r e a m s e n t e r i n g t h e v a l l e y o n t h e eas t s i d e . W i t h o u t m o r e d e t a i l e d s u b s u r f a c e i n v e s t i g a t i o n i t i s h a r d t o k n o w e x a c t l y w h e r e t h e r e c h a r g e i s f r o m . T h e D a k i n r e p o r t a l s o i d e n t i f i e d a r e a s o f g r o u n d w a t e r d i s c h a r g e . T h e s e w i l l b e d i s c u s s e d i n a l a t e r s e c t i o n a b o u t t h e i n t e r a c t i o n s b e t w e e n t h e g r o u n d w a t e r a n d s u r f a c e w a t e r . Table 6. Land Use AQ3 Land use AQ3 (area ha) % Agriculture 83.059 6.99 Forest 879.165 73.99 Urban - -Rural Residential 184.304 15.51 Other" 38.522 3.24 Total 1188.223 100.00 a = Other includes (water, road, wetland/non-forested riparian, greenhouse) M i r a c l e V a l l e y w a s t h e o n l y a r e a o f t h e s t u d y w h e r e t h e r e w e r e e n o u g h w e l l l o g s a v a i l a b l e i n t h e B C w e l l d a t a b a s e t o a l l o w f o r t h e c r e a t i o n o f p r o f i l e s . T h r e e c r o s s - s e c t i o n s ( p r o f i l e s ) w e r e c r e a t e d u s i n g w e l l l o g s f r o m t h e B C g o v e r n m e n t " f i n d a w e l l " w e b s i t e . T h i s l a b o u r i n t e n s i v e p r o c e s s i n v o l v e d s e a r c h i n g t h i s d a t a b a s e f o r a l l p o s s i b l e w e l l l o g s i n t h e s t u d y a r e a . M a n y w e l l l o g s c o n t a i n e d i n c o m p l e t e i n f o r m a t i o n . F o r e v e r y w e l l l o g tha t w a s d e t e r m i n e d t o b e i n t h e H a t z i c V a l l e y t h e e x a c t l o c a t i o n h a d t o b e f o u n d a n d m a p p e d . M a n y l o g s w e r e n o t u s e a b l e b e c a u s e t h e l o g d i d n o t h a v e a d e q u a t e s t ree t o r l o t i n f o r m a t i o n t o a l l o w t h e l o c a t i o n t o b e m a p p e d . O t h e r l o g s d i d n o t c o n t a i n a n y p r o f i l e i n f o r m a t i o n . T h e l o g s t ha t d i d h a v e p r o f i l e i n f o r m a t i o n a n d c o u l d b e g i v e n a s p e c i f i c l o c a t i o n w i t h i n t he a q u i f e r v a r i e d g r e a t l y i n d e t a i l . P r o f i l e s h a v e a l s o b e e n c r e a t e d i n t h e v i c i n i t y o f t h e q u a r r y b y P H C L a n d D a k i n a n d c a n b e f o u n d i n t h e i r r e s p e c t i v e r e p o r t s . 2 9 Figure 7. Locat ions of Wel l Log Prof i les 30 North 200 400 600 800 Distance (m) 1000 1200 1400 1600 1800 2000 0.0 5.0 10.0 o Q 15.0 Gravel - Till BTopsoil Gravel with Grey Clay Gravel, Sand Boulders Clay, till and boulders Clay with of Sand Sand and Gravel Wet sandy| o clay A Silty sand C l a y -Till - Bou lde r " Clay with traces of Sand and gravel Till Clay 0) 5 Bandy gravel pSanG| with traces of clay _ Clay with sand and gravel Gravel A Sand and Gravell 20.0 25.0 Xilay with G rave l ' ' GraveJ^ome clay Gravel and sand '••-Gravel Gravel | 30.0 1 — Figure 8. Well Profile 1. Sylvester Road 31 t North 0 500 1000 Distance (m) 1500 2000 2500 3000 0.0 10.0 20.0 ^ 30.0 JZ Q. 40.0 Q "53 50.0 60.0 70.0 80.0 90.0 * \ 1 Ground Sur face 1 q J Al lan Lake \ \ A - — • A - — — — — — — — — — A Tilly Clay C l a y V Cla7 N Clay 9 s s s < •Clay Clay Clay Stoney Clay ? Sand and Gravel Clay and Rocks ? • TillT" —— • Gravfil Clay ' ^Gravel and Till Sand and Gravel ^=-^=XSandstone ^Sand 7 ? IcTavel Gravel and Boulders * Gravel • ? Clay and sandstone ? ^ Sand • Elevat ion est imated within 20m using 2 0 m contour l ines from Trim GIS layer Figure 9. Well Log Profile 2. Hartley Road 32 North o 500 1000 Distance (m) 1500 2000 2500 3000 10.0 20.0 _ 30.0 E Q. 40.0 Q 50.0 60.0 70.0 80.0 Till Brown Clay Brown Cla Blue Clay - trace Gravel Blue Clay> Blue Clay. Fine Sand Fine grey sand 1 San Tilll Brown Sandy Clay Ground Surface Clay Grey Clay Blue Clay - trace of gravel ~^nr i -aacLGravel Gravel with binder Blue Clay / B r own Gravel Clay and Gravel Sand and Gravel Sand and Gravel Gravel Figure 1 0 . Well Log Profile 3 . Stave Lake Road 33 3.0 Methodology T h r e e s o u r c e s o f d a t a w e r e u s e d f o r t h e m a j o r i t y o f t h e a n a l y s i s o f t h i s p r o j e c t . T h e f i r s t w a s w a t e r q u a l i t y d a t a o b t a i n e d f r o m t h e a n a l y s i s o f s u r f a c e a n d g r o u n d w a t e r s a m p l e s , t he s e c o n d w a s s u r v e y r e s u l t s f r o m a s u r v e y g i v e n t o a l l r e s i d e n t s w h o s u p p l i e d g r o u n d w a t e r s a m p l e s a n d t h e t h i r d w a s l a n d u s e i n f o r m a t i o n c r e a t e d u s i n g a G e o g r a p h i c a l I n f o r m a t i o n S y s t e m ( G I S ) . L a n d u s e t h r o u g h o u t t h e v a l l e y w a s m a p p e d a n d t h e n d e t a i l e d d e s c r i p t i o n s o f t h e l a n d u s e s u r r o u n d i n g e a c h w e l l w a s c a l c u l a t e d u s i n g t h e f e a t u r e s o f t h e G I S p r o g r a m . F i n a l l y , n o n - p a r a m e t r i c s t a t i s t i c a l t e c h n i q u e s w e r e u s e d t o q u a n t i f y t h e r e l a t i o n s h i p s b e t w e e n t h e t h r e e t y p e s o f d a t a . T h e f o l l o w i n g s e c t i o n s d e s c r i b e i n d e t a i l t he m e t h o d s u s e d f o r d a t a c o l l e c t i o n a n d a n a l y s i s . 3.1 Groundwater Survey and Questionnaire 3.1.1 Participant Selection T h e m e t h o d f o r t he c o l l e c t i o n o f g r o u n d w a t e r s a m p l e s w a s b a s e d o n a p r e v i o u s g r o u n d w a t e r i n v e s t i g a t i o n i n t h e L o w e r F r a s e r V a l l e y ( L F V ) ( S c h r e i e r et al., 1 9 9 6 ) . T w o h u n d r e d r e s i d e n t s f r o m w i t h i n t h e s t u d y a r e a w e r e i n v i t e d b y l e t t e r t o p a r t i c i p a t e i n t he g r o u n d w a t e r s u r v e y . I n r e t u r n f o r p r o v i d i n g g r o u n d w a t e r s a m p l e s a t t w o d i f f e r e n t t i m e s o f y e a r t h e p a r t i c i p a n t s r e c e i v e d f r e e n i t r a t e a n a l y s i s o f t h e i r w e l l w a t e r . P o t e n t i a l p a r t i c i p a n t s w e r e c h o s e n f r o m a d a t a b a s e Figure 11. Locat ion of Wel ls Sampled 3 4 p r o v i d e d b y t h e F r a s e r V a l l e y R e g i o n a l D i s t r i c t ( F V R D ) . T h e d a t a b a s e i n i t i a l l y h a d 9 6 0 e n t r i e s r e p r e s e n t i n g e a c h p r o p e r t y i n t h e v a l l e y . B a s e d o n t he o w n e r a d d r e s s field, n o n - p e r m a n e n t r e s i d e n t s w e r e r e m o v e d f r o m t h e l i s t . M a n y r e s i d e n t s o w n m o r e t h a n o n e p r o p e r t y i n t h e v a l l e y a n d t h e l i s t w a s m o d i f i e d s o t h a t e a c h p e r m a n e n t r e s i d e n t o n l y a p p e a r e d i n t h e l i s t o n c e . F r o m t h i s m o d i f i e d l i s t 2 0 0 p r o p e r t y o w n e r s w e r e s e l e c t e d to r e c e i v e a n i n v i t a t i o n t o p a r t i c i p a t e i n t h e s t u d y . T h e 2 0 0 n a m e s w e r e r a n d o m l y c h o s e n f r o m a l l a r e a s i n t h e v a l l e y i n o r d e r t o m a x i m i z e t h e s p a t i a l v a r i a t i o n o f t h e s a m p l e s . I n a d d i t i o n t o t h e l e t t e r s s e n t t o t h e s e 2 0 0 p a r t i c i p a n t s a p r e s s r e l e a s e a b o u t t h e s t u d y w a s p u b l i s h e d i n a l o c a l n e w s p a p e r i n v i t i n g t h e g e n e r a l p u b l i c o f t h e a r e a t o p a r t i c i p a t e as w e l l ( s e e A p p e n d i x 1 f o r c o p y o f t h e l e t t e r o f i n v i t a t i o n a n d A p p e n d i x 2 f o r a c o p y o f t h e P r e s s R e l e a s e ) . B i l l W a l s h , t h e N o r t h F r a s e r V a l l e y W a t e r s h e d S t e w a r d s h i p C o o r d i n a t o r v o l u n t e e r e d t o b e t h e l o c a l c o n t a c t f o r t h e p r o j e c t a n d c o l l e c t e d t h e n a m e s o f w i l l i n g p a r t i c i p a n t s . A p p r o x i m a t e l y 7 5 h o u s e h o l d s v o l u n t e e r e d t o p a r t i c i p a t e i n t h e s t u d y ( s e e f i g u r e 11 f o r l o c a t i o n o f w e l l s s a m p l e d . ) P r i v a t e w e l l s w e r e s a m p l e d b e c a u s e t h i s i s t he m o s t p r a c t i c a l w a y t o s a m p l e m a n y d i f f e r e n t s i t e s a n d g e t a n o v e r v i e w o f t h e w a t e r q u a l i t y i n t h e r e g i o n w i t h o u t c r e a t i n g n e w i n f r a s t r u c t u r e ( b o r e h o l e s , m o n i t o r i n g w e l l s , e t c . ) . It i s r e c o g n i z e d t ha t t h e t e s t i n g o f p r i v a t e w e l l s m a y h i g h l i g h t l o c a l i z e d w a t e r q u a l i t y p r o b l e m s r a t h e r t h a n r e g i o n a l p r o b l e m s t h e r e b y g i v i n g a f a l s e i m p r e s s i o n o f t h e o v e r a l l q u a l i t y o f w a t e r i n t h e a q u i f e r ( B a k e r , 1 9 9 0 ) . H o w e v e r , t h e r e c o g n i t i o n o f l o c a l p r o b l e m s i s c r u c i a l f o r t h e i n d i v i d u a l s u s i n g t h e w e l l s a n d , a s t h e p u r p o s e o f t h i s s t u d y w a s to i n v e s t i g a t e t h e q u a l i t y o f d r i n k i n g w a t e r , s a m p l i n g t a p w a t e r w a s c o n s i d e r e d t o b e t h e b e s t w a y t o d e t e r m i n e t h e q u a l i t y o f t h e g r o u n d w a t e r at t h e p o i n t o f u s e . M a n y o t h e r s t u d i e s h a v e f o u n d t h e t e s t i n g o f p r i v a t e w e l l s t o b e a p r a c t i c a l m e t h o d o f g a t h e r i n g r e g i o n a l p o i n t o f u s e g r o u n d w a t e r q u a l i t y d a t a ( G o s s et al, 1 9 9 8 ; L e g a u l t , 2 0 0 0 ; J a q u e s a n d R o h d e , 2 0 0 1 ; R u t t e r et al, 2 0 0 0 ; M u r p h y , 1 9 9 2 ; B o r c h a r d t et al, 2 0 0 3 ; T u t h i l l et al, 1 9 9 8 ; R e i d et al, 2 0 0 3 ; B a k e r 1 9 9 0 ; S c h r e i e r et al, 1 9 9 6 ; S c h r e i e r et al, 2 0 0 3 ) . 3.1.2 Groundwater Survey - Data Collection G r o u n d w a t e r s a m p l e s w e r e c o l l e c t e d t w i c e , o n J u l y 2 8 t h , 2 0 0 2 a n d o n M a r c h 1 0 t h , 2 0 0 3 . T h e s a m p l i n g w a s d o n e t w i c e i n o r d e r t o o b s e r v e s e a s o n a l v a r i a t i o n i n t h e p a r a m e t e r s m e a s u r e d a n d t o s a m p l e w h e n t h e w a t e r t a b l e w a s a t d i f f e r e n t h e i g h t s . T h r e e t e a m s o f v o l u n t e e r s o r g a n i z e d b y L e i g h L e h m a n n , s e c r e t a r y o f t h e M c C o n n e l l C r e e k / H a t z i c P r a i r i e r a t e - p a y e r s a s s o c i a t i o n , h e l p e d t o d i s t r i b u t e t h e b o t t l e s a n d to c o l l e c t t h e s a m p l e s f r o m a r o u n d t h e v a l l e y . V o l u n t e e r s d i s t r i b u t e d s a m p l e b o t t l e s a w e e k b e f o r e s a m p l i n g . E a c h p a r t i c i p a n t w a s g i v e n a s t e r i l e ( a c i d w a s h e d ) s a m p l e b o t t l e a l o n g w i t h a s h o r t s u r v e y a n d i n s t r u c t i o n s f o r h o w t o t a k e t h e w a t e r s a m p l e ( s e e a p p e n d i x 3 a n d 5 ) . O n t h e s a m p l i n g d a t e , p a r t i c i p a n t s f i l l e d t h e s a m p l e b o t t l e w i t h t a p w a t e r ( w a t e r f r o m t h e i r w e l l ) b e t w e e n 7 a n d 9 a m . T h e y w e r e a s k e d t o r u n t h e i r t a p s f o r 5 m i n u t e s b e f o r e filling t h e b o t t l e s i n o r d e r t o m i n i m i z e t h e i n f l u e n c e o f t h e i r w a t e r p i p e s o n t h e q u a l i t y o f t h e w a t e r . I n t h e s u m m e r , c a r e w a s t a k e n t o e n s u r e t ha t t h e b o t t l e s w e r e n o t l e f t i n d i r e c t s u n l i g h t s o as to 35 n o t d e g r a d e t h e n i t r a t e i n t h e s a m p l e s . R e s i d e n t s w e r e n o t i f i e d o f t h e r e s u l t s o f t h e i r a n a l y s i s w i t h i n t w o w e e k s o f s a m p l e c o l l e c t i o n ( s e e a p p e n d i x 4 f o r s a m p l e o f t he g r o u n d w a t e r r e s u l t s l e t t e r . ) 3.1.3 Chemical Analysis T h e c o l l e c t e d w a t e r s a m p l e s w e r e p u t o n i c e a n d b r o u g h t t o t h e U B C p e d o l o g y l a b o r a t o r y w h e r e t h e y w e r e a n a l y z e d f o r s e v e r a l c h e m i c a l p a r a m e t e r s . p H w a s m e a s u r e d u s i n g a n O r i o n 4 2 0 A p H m e t e r w i t h a u t o - c a l i b r a t i o n u s i n g t w o b u f f e r s . C o n d u c t i v i t y w a s m e a s u r e d u s i n g a B a c h - S i m p s o n l i m i t e d C o n d u c t i v i t y M e t e r t y p e C D M 2 e , N o . 1 2 1 3 2 3 w i t h a n e l e c t r o d e f r o m r a d i o m e t e r a n a l y t i c a l : p a r t 9 4 5 -0 0 0 . T h e p H m e t e r a n d t h e c o n d u c t i v i t y m e t e r w e r e c a l i b r a t e d t o k n o w n s t a n d a r d s p r i o r t o e a c h u s e . A s u i t e o f 2 1 e l e m e n t s i n c l u d i n g a l u m i n i u m , a r s e n i c , b o r o n , b a r i u m , c a l c i u m , c a d m i u m , c o b a l t , c h r o m i u m , c o p p e r , i r o n , p o t a s s i u m , m a g n e s i u m , m a n g a n e s e , m o l y b d e n u m , s o d i u m , n i c k e l , p h o s p h o r u s , s e l e n i u m , s i l i c o n , s t r o n t i u m a n d z i n c w e r e m e a s u r e d u s i n g a V a r i a n V i s t a P r o R a d i a l C C D S i m u l t a n e o u s I C P - O E S . N i t r a t e - N , A m m o n i a - N a n d O r t h o p h o s p h a t e - P w e r e a n a l y z e d u s i n g a Q u i k C h e m F I A + 8 0 0 0 S e r i e s m o d e l f r o m L a c h a t I n s t r u m e n t s . T h e n i t r a t e w a s a n a l y s e d b y Q u i k C h e m m e t h o d 1 2 - 1 0 7 - 0 4 - 1 - B . I n t h i s m e t h o d n i t r a t e i s q u a n t i t a t i v e l y r e d u c e d t o n i t r i t e b y p a s s a g e o f t h e s a m p l e t h r o u g h a c o p p e r i z e d c a d m i u m c o l u m n . T h e n i t r i t e ( r e d u c e d n i t r a t e p l u s o r i g i n a l n i t r i t e ) i s t h e n d e t e r m i n e d b y d i a z o t i s i n g w i t h s u l f a n a l a m i d e f o l l o w e d b y c o u p l i n g w i t h N - ( 1 - n a p h t h y l ) e t h y l e n e d i a m i n e d i h y d r o c h l o r i d e . T h e r e s u l t i n g w a t e r - s o l u b l e d y e h a s a m a g e n t a c o l o u r w h i c h i s r e a d a t 5 2 0 n m ( Q u i k C h e m m e t h o d 1 2 - 1 0 7 - 0 4 -1 - B ) . T h e o r t h o p h o s p h a t e w a s a n a l y z e d b y Q u i k C h e m m e t h o d 1 0 - 1 1 5 - 0 1 - 1 - A . I n t h i s m e t h o d t h e o r t h o p h o s p h a t e i o n r e a c t s w i t h a m m o n i u m m o l y b d a t e a n d a n t i m o n y p o t a s s i u m t a r t r a te u n d e r a c i d i c c o n d i t i o n s t o f o r m a c o m p l e x . T h i s c o m p l e x i s r e d u c e d w i t h a s c o r b i c a c i d t o f o r m a b l u e c o m p l e x t ha t a b s o r b s l i g h t at 8 8 0 n m . T h e a b s o r b a n c e i s p r o p o r t i o n a l t o t h e c o n c e n t r a t i o n o f o r t h o p h o s p h a t e i n t h e s a m p l e ( D i a m o n d , 1 9 9 5 ) . A m m o n i a i s a n a l y s e d b y Q u i k C h e m m e t h o d 1 0 - 1 0 7 - 0 6 - 2 - A t h e p r i n c i p l e o f w h i c h i s as f o l l o w s , w h e n a m m o n i a i s h e a t e d w i t h s a l i c y l a t e a n d h y p o c h l o r i t e i n a n a l k a l i n e p h o s p h a t e b u f f e r a n e m e r a l d g r e e n c o l o u r i s p r o d u c e d w h i c h i s p r o p o r t i o n a l t o t h e a m m o n i a c o n c e n t r a t i o n . T h e c o l o u r i s i n t e n s i f i e d b y t h e a d d i t i o n o f s o d i u m n i t r o p r u s s i d e ( P r o k o p y , 1 9 9 2 ) . Q u a l i t y w a s a s s u r e d b y u s i n g b o t t l e s t ha t w e r e a c i d w a s h e d p r i o r t o u s e a n d b y t h e r e q u i r e m e n t t o r u n t h e t a p f o r 5 m i n u t e s p r i o r t o f i l l i n g t h e s a m p l i n g b o t t l e . T h e l a b o r a t o r y t e c h n i c i a n s u s e s t a n d a r d s e v e r y 1 0 s a m p l e s t o e n s u r e p r o p e r c a l i b r a t i o n o f t h e e q u i p m e n t . T w o b l i n d d u p l i c a t e s w e r e u s e d i n t h e w i n t e r s a m p l i n g . T h e r e s u l t s o f t h e d u p l i c a t e s a re f o u n d i n a p p e n d i x 6 . 3.1.4 Coliform Analysis S e l e c t e d s a m p l e s t ha t h a d n i t r a t e - N l e v e l s a b o v e 4 m g / L w e r e a n a l y z e d f o r t o t a l a n d f e c a l c o l i f o r m s b y t h e B r i t i s h C o l u m b i a C e n t r e f o r D i s e a s e C o n t r o l ( B C C D C ) . T h e f o l l o w i n g m e t h o d w a s u s e d f o r c o l i f o r m e n u m e r a t i o n . A l l s a m p l e s a r e f i l t e r e d a s f o l l o w s : p u t a 0 . 4 5 u m f i l t e r o n t h e b a s e o f t h e f u n n e l t h e n p u t 36 t h e f u n n e l o n . P o u r i n a b o u t 2 0 m l o f b u f f e r a n d p i p e t t e a n a l i q u o t o f w a t e r ( f o r t h e w a t e r s h e d a n d s u r f a c e w a t e r , 1 a n d 0 . 1 m l w a s c h o s e n f o r m o s t o f t h e s a m p l e s ) i n t o t h e b u f f e r . T u r n o n t h e f u n n e l t a p a n d d r a i n t h e s a m p l e a n d b u f f e r , t h e n r i n s e t h e s a m p l e 2 x s w i t h a b o u t 3 0 m l o f b u f f e r . F o r t o t a l c o l i f o r m , t a k e t h e f i l t e r o u t a n d p u t o n t o L e s E n d o A g a r p l a t e . I n c u b a t e t h e p l a t e f o r 2 2 - 2 4 h o u r s at 3 5 + 0 . 5 ° C . F o r f e c a l c o l i f o r m , t a k e t h e f i l t e r o u t a n d p u t o n t o m - F C A g a r p l a t e a n d i n c u b a t e t h e p l a t e f o r 2 4 + 2 h o u r s at 4 4 . 5 ± 0 . 2 ° C . A f t e r i n c u b a t i o n , a l l p l a t e s a r e r e a d u s i n g s t e r e o m i c r o s c o p e : 1) f o r t o t a l c o l i f o r m , t y p i c a l c o l o n i e s ( a re t h o s e f o r m g r e e n m e t a l l i c s h e e n o n e ) a n d a t y p i c a l c o l o n i e s ( a r e d a r k r e d w i t h o r w i t h o u t s h e e n ) w i l l b e c o u n t e d a n d v e r i f i e d . T r a n s l u c e n t o r p a l e p i n k c o l o n i e s a r e n o n - c o l i f o r m s a n d w o n ' t b e v e r i f i e d . T y p i c a l a n d a t y p i c a l c o l o n i e s w i l l b e t r a n s f e r r e d t o l a u r y l t r y p t o s e b r o t h a n d B r i l l i a n t G r e e n b i l e s a l t b r o t h a n d i n c u b a t e d at 3 5 + 0 . 5 ° C f o r c o n f i r m a t i o n . G a s f o r m e d i n b r i l l i a n t g r e e n b i l e s a l t b r o t h w i l l b e c o n s i d e r e d p o s i t i v e t o t a l c o l i f o r m . 2 ) F o r f e c a l c o l i f o r m , t y p i c a l c o l o n i e s ( b l u e c o l o n i e s ) a n d a t y p i c a l c o l o n i e s ( g r e y i s h b l u e , g r e e n i s h b l u e ) w i l l b e v e r i f i e d b y t r a n s f e r r i n g t o l a u r y l t r y p t o s e b r o t h a n d i n c u b a t e d at 3 5 + 0 . 5 ° C f o r 4 8 h o u r s . I f l a u r y l t r y p t o s e b r o t h i s p o s i t i v e ( g a s f o r m a t i o n ) , a l o o p f u l w i l l b e t r a n s f e r r e d to E C b r o t h f o r c o n f i r m a t i o n a n d i n c u b a t e d a t 4 4 . 5 ° C f o r 2 4 h o u r s . P o s i t i v e ( g a s f o r m a t i o n ) E C w i l l b e c o n s i d e r e d as F e c a l p o s i t i v e . A f t e r a l l c o n f i r m a t i o n i s d o n e , c o u n t w i l l b e c a l c u l a t e d a c c o r d i n g t o t h e c o n f i r m a t i o n r e s u l t s ( W o n g , 2 0 0 4 ) . 3.1.5 Opinion Survey A s h o r t s u r v e y , b a s e d o n a p r e v i o u s s u r v e y d i s t r i b u t e d b y S c h r e i e r et al., ( 1 9 9 6 ) , w a s i n c l u d e d w i t h t h e s a m p l i n g b o t t l e s t o g e t m o r e i n f o r m a t i o n a b o u t t h e w e l l s s a m p l e d s u c h a s t h e a g e a n d d e p t h o f t h e w e l l s a s w e l l as i n f o r m a t i o n a b o u t t h e h a b i t s a n d p e r c e p t i o n s o f t h e o w n e r s o f t h e s a m p l e d w e l l s . Q u e s t i o n s w e r e a s k e d a b o u t w a t e r t r e a t m e n t , l a n d u s e n e a r t h e w e l l s , s e p t i c s y s t e m s a n d p e r c e p t i o n s o f t h e i m p o r t a n c e o f v a r i o u s a c t i v i t i e s i n d e g r a d i n g w a t e r q u a l i t y . A c o p y o f t h e s u r v e y i s i n c l u d e d i n a p p e n d i x 5 . 3.2 Stream Sampling S t r e a m s a m p l e s w e r e t a k e n f r o m 19 l o c a t i o n s t h r o u g h o u t t he s t u d y a r e a b e t w e e n M a y 2 0 0 2 a n d M a y 2 0 0 3 . p H , C o n d u c t i v i t y a n d t e m p e r a t u r e w e r e m e a s u r e d i n s t r e a m u s i n g a n d O a k t o n W a t e r p r o o f p H / c o n d u c t i v i t y d e l u x e m e t e r k i t : m o d e l n o . W D - 3 5 6 3 1 - 6 0 . S i n c e t e m p e r a t u r e a n d d i s t a n c e a f f e c t t h e c o n d u c t i v i t y l e v e l s t h e p r o b e i s c o n s t r u c t e d w i t h e l e c t r o d e s a s t a n d a r d d i s t a n c e a p a r t ( 1 c m ) a n d t h e a b i l i t y t o c o r r e c t t h e t e m p e r a t u r e to 2 5 ° C . C o n d u c t i v i t y m e a s u r e m e n t s t ha t a r e c o r r e c t e d f o r t e m p e r a t u r e a r e c a l l e d s p e c i f i c c o n d u c t i v i t y m e a s u r e m e n t s . N i t r a t e - N , A m m o n i a - N a n d O r t h o p h o s p h a t e - P w e r e a n a l y z e d i n t h e l a b u s i n g t h e s a m e e q u i p m e n t a n d m e t h o d s a s f o r t h e g r o u n d w a t e r s a m p l e s ( s e e s e c t i o n 3 . 1 . 3 ) . 37 F i g u r e 12 s h o w s t h e l o c a t i o n o f t h e s t r e a m s a m p l i n g s t a t i o n s . S a m p l e s w e r e t a k e n i n s t e r i l e ( a c i d w a s h e d ) b o t t l e s tha t w e r e r i n s e d t w i c e w i t h w a t e r f r o m t h e s a m p l i n g l o c a t i o n p r i o r t o c o l l e c t i o n . Figure 12. Locat ion of Stream Sampl ing Stat ions 3.3 GIS Database. A s p a t i a l d a t a b a s e w a s c r e a t e d i n t he A r c V i e w 3 . 2 G e o g r a p h i c a l I n f o r m a t i o n S y s t e m . L o c a t i o n s o f t h e w e l l s s a m p l e d w e r e p l o t t e d u s i n g a c o m b i n a t i o n o f o r t h o p h o t o s a n d C A D ( C o m p u t e r A s s i s t e d D e s i g n ) d r a w i n g s s u p p l i e d b y t h e F V R D . T h e e x a c t l o c a t i o n s o f t he w e l l s w e r e n o t p l o t t e d b u t r a t h e r t h e l o c a t i o n o f t h e h o u s e o n t h e p r o p e r t y w h e r e t h e w e l l s w e r e l o c a t e d . It w a s a s s u m e d tha t t h e w e l l s w e r e r e l a t i v e l y c l o s e t o t h e h o m e s t h e y w e r e s e r v i n g . A m a p r e p r e s e n t i n g t h e l a n d u s e i n t h e v a l l e y w a s c r e a t e d u s i n g t h e o r t h o p h o t o s p r o v i d e d b y t h e F V R D . S e e t a b l e 7 f o r a s u m m a r y o f t h e l a n d u s e c a t e g o r i e s c r e a t e d a n d f i g u r e 2 f o r t h e e n t i r e l a n d u s e m a p . F r o m t h e s e 11 c a t e g o r i e s , 4 w e r e u s e d i n t he a n a l y s i s ; f o r e s t ( 5 ) , a g r i c u l t u r e ( 9 ) , r u r a l r e s i d e n t i a l ( c l e a r i n g ) ( 7 ) a n d u r b a n ( t r a i l e r p a r k a n d s u b d i v i s i o n c o m b i n e d ) ( 4 , 6 ) . T h e r u r a l r e s i d e n t i a l c a t e g o r y 38 e n c o m p a s s e d a l l o f t h e n o n - a g r i c u l t u r a l c l e a r i n g s a n d w a s i n t e n d e d t o c a p t u r e l a n d t h a t w a s n o n - f o r e s t e d b u t w a s n o t b e i n g u s e d t o p r o d u c e c r o p s . It w a s a s s u m e d tha t t h i s l a n d w o u l d h a v e d i f f e r e n t i n p u t s t h a n t h e a g r i c u l t u r a l f i e l d s . M o s t p o l y g o n s c a t e g o r i z e d as r u r a l r e s i d e n t i a l i n c l u d e d h o u s e s a n d s o m e i n c l u d e d b a r n s a n d b a r n y a r d s a s w e l l . F o r e s t c o v e r , a g r i c u l t u r e , r u r a l r e s i d e n t i a l a n d u r b a n w e r e c h o s e n a s t h e f i n a l f o u r l a n d u s e c a t e g o r i e s b e c a u s e t h e y c o v e r e d t h e l a r g e s t a m o u n t o f t h e a r e a a r o u n d t h e w e l l s a n d t h e r e f o r e t h e y c o u l d b e c o n s i d e r e d to b e t h e d o m i n a n t l a n d u s e s i n t h e v a l l e y . T h e s e f o u r c a t e g o r i e s a l s o r e p r e s e n t d i f f e r e n t p o t e n t i a l s t r e s s e s t o t he g r o u n d w a t e r s y s t e m . F o r e x a m p l e i t w o u l d b e e x p e c t e d t ha t f o r e s t e d l a n d w o u l d n o t b e r e c e i v i n g l a r g e i n p u t s o f n u t r i e n t s , t h e a g r i c u l t u r a l l a n d w o u l d h a v e l a r g e n u t r i e n t i n p u t s d u e t o a p p l i c a t i o n s o f m a n u r e a n d c o m m e r c i a l f e r t i l i z e r a n d t h e u r b a n a r e a s w o u l d r e c e i v e n u t r i e n t i n p u t s f r o m s e p t i c s y s t e m s . E a c h w e l l w a s a l s o g i v e n a l o c a t i o n c o d e t h a t c o r r e s p o n d e d t o t h e a q u i f e r i t w a s i n . T h e l o c a t i o n s w e r e d e t e r m i n e d f r o m t h e G I S m a p s o f t h e a q u i f e r s f r o m t h e B r i t i s h C o l u m b i a M i n i s t r y o f W a t e r L a n d a n d A i r P r o t e c t i o n ( W L A P ) a n d o n l y t a k e i n t o a c c o u n t d i f f e r e n c e i n l o c a t i o n a n d n o t i n d e p t h w h e n g r o u p i n g t h e s a m p l e s . Table 7. Land use Categories Coded into GIS 1 B i g S t r e a m s 2 G r e e n h o u s e s 3 L a k e 4 T r a i l e r P a r k 5 F o r e s t 6 S u b d i v i s i o n ( D e n s e R e s i d e n t i a l ) 7 C l e a r i n g ( E x t e n s i v e r u r a l R e s i d e n t i a l , i n c l u d i n g h o b b y f a r m s ) 8 R o a d 9 A g r i c u l t u r a l 1 0 W e t l a n d / n o n f o r e s t / n o n a g r i c u l t u r a l r i p a r i a n 11 H y d r o C u t U s i n g t h e b u f f e r f u n c t i o n o f t h e G I S s o f t w a r e , c i r c l e s ( c a l l e d b u f f e r s ) w i t h r a d i i o f 5 0 , 1 0 0 a n d 2 0 0 m w e r e c r e a t e d s u r r o u n d i n g e a c h w e l l . T h e s e b u f f e r s w e r e t h e n u s e d t o c l i p a c o r r e s p o n d i n g c i r c l e f r o m t h e l a n d u s e m a p a r o u n d e a c h w e l l ( s e e f i g u r e 13 . ) . T h e a r e a o f e a c h l a n d u s e t y p e w i t h i n e a c h b u f f e r w a s c a l c u l a t e d a n d t h e n u s e d t o c a l c u l a t e p e r c e n t a g e s o f l a n d u s e t y p e w i t h i n e a c h b u f f e r . A s i m i l a r p r o c e s s w a s u s e d t o c a l c u l a t e t h e p e r c e n t a g e o f l a n d u s e a s s o c i a t e d w i t h t h e s t r e a m s . I n t h i s c a s e 5 0 a n d 1 0 0 m b u f f e r s w e r e c r e a t e d a r o u n d l i n e d a t a ( s t r e a m s ) r a t h e r t h a n p o i n t d a t a ( w e l l s ) . I n t h e c a s e o f t h e s t r e a m s t a t i o n s , t h e p e r c e n t a g e o f l a n d u s e w a s c a l c u l a t e d f o r t he e n t i r e s t r e a m n e t w o r k u p s t r e a m o f t ha t p o i n t m e a n i n g t h a t t h e l a n d u s e p e r c e n t a g e s a r e c u m u l a t i v e . F i g u r e 13 s h o w s w h a t t h e 1 0 0 m b u f f e r s a r o u n d t h e w e l l s o n A Q 1 l o o k l i k e . 39 1 0 1 Kilometers Figure 13. Land use buffers surrounding wells in AQ1 I n f o r m a t i o n o n t h e s o i l i n t h e a r e a w a s t a k e n f r o m Soils of the Langley-Vancouver Map Area V o l u m e s 1 a n d 2 ( L u t t e r m i d i n g 1 9 8 0 a a n d 1 9 8 0 b ) T h e s o i l t y p e f o r e a c h w e l l w a s d e t e r m i n e d v i s u a l l y a n d t h e n c o d e d i n t o t h e d a t a b a s e . T h e i n f o r m a t i o n t a k e n from t h e s o i l s m a p i s l i s t e d i n a p p e n d i x 7 S u r f i c i a l G e o l o g y w a s a d d e d t o t h e G I S i n t h e s a m e m a n n e r a s s o i l s i n f o r m a t i o n . T h e s u r f i c i a l g e o l o g y w a s t a k e n from A r m s t r o n g ( 1 9 8 0 ) Surficial Geology Mission, British Columbia. A p p e n d i x 7 a l s o s h o w s t h e t e x t u r e c l a s s i f i c a t i o n c r e a t e d f r o m t h e s u r f i c i a l g e o l o g y m a p . T h e c a t e g o r i e s w e r e c o d e d s o t ha t l o w e r n u m b e r s r e p r e s e n t e d t h e l e a s t p e r m e a b l e o p t i o n a n d t h e h i g h e r n u m b e r s r e p r e s e n t e d m o r e p e r m e a b l e c o n d i t i o n s . 3.4 Statistical Analysis D a t a a n a l y s i s w a s p e r f o r m e d u s i n g n o n - p a r a m e t r i c s t a t i s t i c a l t e c h n i q u e s . T h e s e m e t h o d s , a l t h o u g h l e s s p o w e r f u l t h a n t r a d i t i o n a l t e c h n i q u e s , a r e u s e f u l w h e n t h e a s s u m p t i o n s o f p a r a m e t r i c p r o c e d u r e s a r e n o t m e t . N o n - p a r a m e t r i c t e c h n i q u e s a r e u s e d w h e n d a t a i s n o t n o r m a l l y d i s t r i b u t e d a n d w h e n s o m e o f t h e 40 d a t a t o b e a n a l y z e d i s o r d i n a l i n n a t u r e r a t h e r t h a n c o n t i n u o u s ( S i e g e l , 1 9 5 6 ) . T h e s e p r o c e d u r e s c o m p a r e p o p u l a t i o n m e d i a n s r a t h e r t h a n p o p u l a t i o n m e a n s . I n o r d e r t o d e t e r m i n e i f t h e u s e o f n o n - p a r a m e t r i c m e t h o d s w a s a p p r o p r i a t e e a c h p a r a m e t e r w a s t e s t e d f o r n o r m a l c y u s i n g t h e o n e s a m p l e K o l m o g o r o v -S m i r n o v tes t . T h i s tes t c o m p a r e s a n o b s e r v e d c u m u l a t i v e d i s t r i b u t i o n f u n c t i o n t o a t h e o r e t i c a l c u m u l a t i v e d i s t r i b u t i o n . L a r g e s i g n i f i c a n c e v a l u e s ( > 0 . 0 5 ) i n d i c a t e d t ha t t h e o b s e r v e d d i s t r i b u t i o n c o r r e s p o n d s t o t h e t h e o r e t i c a l d i s t r i b u t i o n . E a c h c h e m i c a l p a r a m e t e r f o r w i n t e r a n d s u m m e r w a s t e s t e d a g a i n s t a n o r m a l d i s t r i b u t i o n t e s t i n g t h e f o l l o w i n g h y p o t h e s i s . H0 = the data conforms to a normal distribution Hj = the data does not conform to a normal distribution T h e n u l l h y p o t h e s i s w a s r e j e c t e d f o r a l l b u t o n e p a r a m e t e r . O n l y s i l i c o n w a s f o u n d t o f o l l o w t h e n o r m a l d i s t r i b u t i o n , t ha t i s h a v i n g a s i g n i f i c a n c e v a l u e g r e a t e r t h a n 0 . 0 5 . T h e s a m e r e s u l t s w e r e o b t a i n e d b y l o o k i n g a t t h e s k e w n e s s o f t h e v a r i a b l e s . O n l y s i l i c o n ( s u m m e r a n d w i n t e r ) d i d n o t h a v e a s k e w n e s s v a l u e g r e a t e r t h a n o n e , a g a i n i n d i c a t i n g t ha t t h i s w a s t h e o n l y v a r i a b l e t h a t f o l l o w s a n o r m a l d i s t r i b u t i o n . T h e u s e o f n o n - p a r a m e t r i c m e t h o d s i s f u r t h e r j u s t i f i e d b e c a u s e s o m e o f t h e d a t a i s o r d i n a l i n n a t u r e . A l l s t a t i s t i c a l a n a l y s i s w a s c a r r i e d o u t u s i n g t h e s t a t i s t i c a l s o f t w a r e p a c k a g e S P S S ( v e r s i o n 1 1 . 5 ) a n d as s u c h i s s u b j e c t t o t h e l i m i t a t i o n s o f t h i s p r o g r a m . T h e f o l l o w i n g s e c t i o n s w i l l d e s c r i b e t h e a n a l y t i c a l t e c h n i q u e s as w e l l as t h e h y p o t h e s e s t e s t e d . 3.4.1 Correlation S p e a r m a n ' s R a n k C o r r e l a t i o n c o e f f i c i e n t s ( r ) w e r e c a l c u l a t e d i n o r d e r t o s u m m a r i z e t h e s t r e n g t h a n d d i r e c t i o n ( n e g a t i v e o r p o s i t i v e ) o f t h e r e l a t i o n s h i p b e t w e e n t w o v a r i a b l e s . T h e c o e f f i c i e n t s a r e a l w a y s b e t w e e n n e g a t i v e o n e a n d p o s i t i v e o n e . A n e g a t i v e c o e f f i c i e n t m e a n s t h e r e i s a n i n v e r s e r e l a t i o n s h i p b e t w e e n t h e t w o v a r i a b l e s b e i n g c o m p a r e d . A s o n e v a r i a b l e i n c r e a s e s , t h e o t h e r d e c r e a s e s . C o n v e r s e l y , a p o s i t i v e c o e f f i c i e n t m e a n s t h e r e i s a p o s i t i v e r e l a t i o n s h i p , a s o n e p a r a m e t e r i n c r e a s e s s o d o e s t h e o t h e r . S i g n i f i c a n c e o f c o r r e l a t i o n s c a n b e t e s t e d u s i n g t h e f o l l o w i n g h y p o t h e s i s : H 0 : There is no relationship between the two sets of data H i : There is a relationship between the two sets of data 3.4.2 Mann-Whitney U Test T h e M a n n - W h i t n e y U tes t , t h e n o n - p a r a m e t r i c a l t e r n a t i v e t o t h e u n p a i r e d t - tes t , w a s u s e d i n s i t u a t i o n s w h e r e p a r a m e t e r s h a d b e e n s p l i t i n t o t w o g r o u p s ( f o r e x a m p l e s u m m e r a n d w i n t e r ) a n d i t w a s n e c e s s a r y t o tes t i f t he g r o u p s w e r e s i g n i f i c a n t l y d i f f e r e n t f r o m e a c h o t h e r . T h i s t e c h n i q u e t e s t e d t h e f o l l o w i n g h y p o t h e s i s : H 0 : There is no difference between the medians of the populations that the samples come from. . , H p There is a significant difference between the medians of the populations that the samples come from. 4 1 3.4.3 Kruskal-Wallis Test T h e K r u s k a l - W a l l i s ( K - W ) tes t i s t h e n o n - p a r a m e t r i c e q u i v a l e n t t o t h e a n a l y s i s o f v a r i a n c e ( A N O V A ) . T h i s tes t i s u s e d t o tes t f o r s i g n i f i c a n t d i f f e r e n c e s b e t w e e n t h r e e o r m o r e g r o u p s u s i n g t h e f o l l o w i n g h y p o t h e s i s . H 0 : T h e p o p u l a t i o n s a l l h a v e the s ame m e d i a n . H i : A t least one o f the p o p u l a t i o n s has a s i g n i f i c a n t l y d i f fe ren t m e d i a n . T h e r e s u l t s o f t h e K r u s k a l - W a l l i s tes t d o n o t s h o w w h i c h g r o u p s a r e d i f f e r e n t f r o m t h e o t h e r s ; a r e j e c t i o n o f t h e n u l l h y p o t h e s i s o n l y t e l l s u s t ha t a s l e a s t o n e o f t h e g r o u p s i s s i g n i f i c a n t l y d i f f e r e n t t h a n o n e o f t h e o t h e r s . W h e n u s i n g p a r a m e t r i c m e t h o d s , p r o c e d u r e s s u c h as B o n f e r r o n i , T u k e y a n d S h e f f e a r e a v a i l a b l e t o tes t w h i c h g r o u p s a r e d i f f e r e n t f r o m e a c h o t h e r a f t e r r u n n i n g a o n e - w a y A N O V A . T h e s e t e c h n i q u e s h a v e b e e n d e v e l o p e d t o d e t e r m i n e w h i c h g r o u p s a r e d i f f e r e n t b e c a u s e t h e n u m b e r o f c o m p a r i s o n s m a d e w i l l i n f l u e n c e t h e p r o b a b i l i t y o f m a k i n g a t y p e I e r r o r ( s a y i n g t ha t t h e r e i s a d i f f e r e n c e w h e n t h e t w o g r o u p s a r e r e a l l y f r o m t h e s a m e p o p u l a t i o n ) . F o r e x a m p l e , i f o n e m a d e s i x c o m p a r i s o n s i n t h i s m a n n e r t h e o v e r a l l p r o b a b i l i t y o f m a k i n g a t y p e I e r r o r w o u l d b e 0 . 2 6 r a t h e r t h a n 0 . 0 5 ( Z a r , 1 9 8 4 ) . M a n y d e s c r i p t i o n s o f t h e K r u s k a l - W a l l i s tes t d o n o t g i v e a n y i n s t r u c t i o n s o n h o w t o d e t e r m i n e w h i c h g r o u p s a r e d i f f e r e n t f o l l o w i n g t h i s t es t ( S i e g e l , 1 9 5 6 ; S t a t s o f t , 2 0 0 2 ) . T h e m o s t c o m m o n l y q u o t e d s o u r c e o f m e t h o d s f o r s i m i l a r n o n - p a r a m e t r i c p r o c e d u r e s i s Z a r ( 1 9 8 4 ) b u t t h e s e a r e n o t i n c l u d e d i n t h e a n a l y t i c a l c a p a b i l i t i e s o f t h e S P S S s o f t w a r e . I n o r d e r t o c o n t i n u e t o u s e S P S S f o r s t a t i s t i c a l a n a l y s i s b u t t o a t t e m p t t o l e s s e n t h e i n c r e a s e i n t y p e I e r r o r t ha t r e s u l t s f r o m m a k i n g m u l t i p l e c o m p a r i s o n s u s i n g t h e M a n n -W h i t n e y tes t , t h e f o l l o w i n g m e t h o d w i l l b e u s e d t o d e t e r m i n e w h i c h g r o u p s a r e d i f f e r e n t f r o m e a c h o t h e r a f t e r r u n n i n g a K r u s k a l - W a l l i s tes t . I f t h r e e o r m o r e g r o u p s a r e t o b e c o m p a r e d a K - W tes t w i l l b e u s e d . I f t h e n u l l h y p o t h e s i s i s r e j e c t e d , m e a n i n g t ha t at l e a s t o n e o f t h e g r o u p s i s d i f f e r e n t , b o x p l o t s w i l l b e c r e a t e d t o g i v e a v i s u a l r e p r e s e n t a t i o n o f w h a t i s b e i n g t e s t e d . I n t h i s c a s e t h e b o x p l o t s w i l l b e u s e d to v i s u a l l y d e t e r m i n e w h i c h m e d i a n s a r e c l o s e s t t o g e t h e r . T h e M a n n - W h i t n e y U tes t w i l l b e u s e d t o d e t e r m i n e i f t h e s e m e d i a n s a r e s i g n i f i c a n t l y d i f f e r e n t f r o m e a c h o t h e r . I f t h e y a r e , n o f u r t h e r M a n n -W h i t n e y t es t s n e e d t o b e u s e d a s i t f o l l o w s tha t i f t h e c l o s e s t m e d i a n s a r e s i g n i f i c a n t l y d i f f e r e n t f r o m e a c h o t h e r t h e o t h e r m e d i a n s w i l l b e t o o a n d i t w i l l n o t b e n e c e s s a r y t o t es t t h e o t h e r v a r i a b l e s . I f t h e f i r s t m e d i a n s t e s t e d a r e n o t s i g n i f i c a n t l y d i f f e r e n t f r o m e a c h o t h e r s u b s e q u e n t M a n n - W h i t n e y t es t s w i l l b e u s e d . 3.4.4 Boxplots B o x p l o t s a r e a m e t h o d o f g r a p h i c a l l y d i s p l a y i n g d a t a tha t s h o w s t h e d i s p e r s i o n o f t h e d a t a . I n S P S S t h e b o x c o n s i s t s o f t h e m e d i a n a n d t he i n t e r q u a r t i l e r a n g e . T h e i n t e r q u a r t i l e r a n g e i n c l u d e s 5 0 % o f t h e d i s t r i b u t i o n . T h e w h i s k e r s o n t h e p l o t c a n n o t e x t e n d m o r e t h a n 1.5 t i m e s t h e l e n g t h o f t h e b o x ( t he i n t e r q u a r t i l e r a n g e ) . I f t h e r e a r e v a l u e s g r e a t e r t h a n 1.5 t i m e s t h e i n t e r q u a r t i l e r a n g e t h e y a r e c o n s i d e r e d o u t l i e r s . V a l u e s g r e a t e r t h a n 3 t i m e s t h e i n t e r q u a r t i l e r a n g e a r e c o n s i d e r e d e x t r e m e v a l u e s . O u t l i e r s a r e r e p r e s e n t e d b y a c i r c l e "o" o n t h e b o x p l o t s a n d e x t r e m e v a l u e s a r e r e p r e s e n t e d b y a n a s t e r i s k " * " . 42 3.4.5 Cluster Analysis T h e p u r p o s e o f c l u s t e r a n a l y s i s " i s t o j o i n t o g e t h e r o b j e c t s i n t o s u c c e s s i v e l y l a r g e r c l u s t e r s , u s i n g s o m e m e a s u r e o f s i m i l a r i t y o r d i s t a n c e " ( S t a t s o f t , 2002). C l u s t e r a n a l y s i s i s n o t a s t a t i s t i c a l t e c h n i q u e w h i c h h a s s i g n i f i c a n c e a s s o c i a t e d w i t h i t . It i s a d e s c r i p t i v e t e c h n i q u e t ha t i s u s e d t o l o o k f o r p a t t e r n s i n d a t a as a n e x p l o r a t o r y s t e p i n d a t a a n a l y s i s . U s u a l l y t h i s p r o c e d u r e i s u s e d i n o r d e r t o f i n d u n k n o w n p a t t e r n s i n d a t a . I n h i e r a r c h i c a l c l u s t e r a n a l y s i s ( t he t y p e u s e d f o r t h i s a n a l y s i s ) e a c h o b j e c t b e g i n s i n a s e p a r a t e c l u s t e r a n d t h e y a r e g r a d u a l l y l i n k e d t o g e t h e r i n t o o n e l a r g e c l u s t e r . T h e r e a r e t w o m e a s u r e s t ha t m u s t b e c h o s e n w h e n p e r f o r m i n g a c l u s t e r a n a l y s i s . T h e f i r s t i s t h e d i s t a n c e m e a s u r e . T h e d i s t a n c e m e a s u r e d e t e r m i n e s h o w f a r a p a r t e a c h i n d i v i d u a l c a s e i s f r o m a l l o t h e r c a s e s . T h e E u c l i d i a n d i s t a n c e w a s u s e d i n t h i s a n a l y s i s b e c a u s e i t i s a g o o d m e a s u r e t o u s e o n d a t a t ha t h a s n o t b e e n s t a n d a r d i z e d . T h e s e c o n d m e a s u r e m e n t i s c a l l e d t h e a m a l g a m a t i o n o r l i n k a g e r u l e . T h e s e r u l e s d e t e r m i n e h o w t h e d i s t a n c e b e t w e e n g r o u p s i s m e a s u r e d . T h e m e t h o d c h o s e n f o r t h i s a n a l y s i s i s c a l l e d ' c o m p l e t e l i n k a g e ' o r ' f u r t h e s t n e i g h b o u r ' . T h i s m e t h o d m e a s u r e s t h e f u r t h e s t d i s t a n c e b e t w e e n m e m b e r s o f d i f f e r e n t c l u s t e r s to d e t e r m i n e w h i c h c l u s t e r t o l i n k n e x t . T h i s m e t h o d w a s c h o s e n t h r o u g h a c o m b i n a t i o n o f t r i a l a n e r r o r a n d b e c a u s e i t w a s r e c o m m e n d e d f o r g r o u p s tha t f o r m n a t u r a l l y d i s t i n c t c l u m p s . T h e o u t p u t f r o m t h e a n a l y s i s i s t y p i c a l l y a d e n d o g r a m a n d i t i s l e f t t o t h e d i s c r e t i o n o f t h e r e s e a r c h e r t o d e t e r m i n e h o w m a n y c l u s t e r s a r e a p p r o p r i a t e . 4 3 4.0 Results and Discussion T h e r e s u l t s o f t h e a n a l y s i s o f t h e t h r e e t y p e s o f d a t a m e n t i o n e d i n s e c t i o n 3 ( w a t e r q u a l i t y d a t a , G I S d a t a a n d s u r v e y d a t a ) a r e p r e s e n t e d i n t h i s s e c t i o n . F i r s t , t h e o v e r a l l g r o u n d w a t e r q u a l i t y i s d i s c u s s e d w i t h a f o c u s o n t h o s e p a r a m e t e r s t h a t e x c e e d e d t h e G u i d e l i n e s f o r C a n a d i a n D r i n k i n g W a t e r Q u a l i t y ( G C D W Q ) . T h e n a n e x a m i n a t i o n o f t h e r e l a t i o n s h i p s b e t w e e n p a r a m e t e r s i s m a d e i n c l u d i n g s e a s o n a l v a r i a t i o n , v a r i a t i o n w i t h d e p t h a n d c o r r e l a t i o n s b e t w e e n t h e w a t e r q u a l i t y p a r a m e t e r s . B e c a u s e g r o u n d w a t e r s a m p l e s w e r e t a k e n f r o m t h r e e s e p a r a t e a q u i f e r s , a n a l y s i s w a s d o n e t o d e t e r m i n e i f t h e w a t e r f r o m t h e d i f f e r e n t a q u i f e r s h a d d i s t i n c t c h e m i c a l s i g n a t u r e s . U s i n g t h e G I S d a t a b a s e a n d t h e w a t e r q u a l i t y d a t a b a s e a n e x a m i n a t i o n o f t h e i n t e r a c t i o n s b e t w e e n g r o u n d w a t e r q u a l i t y a n d l a n d u s e w a s m a d e . T h e n e x t s e c t i o n o f a n a l y s i s f o c u s e s o n t h e s u r f a c e w a t e r q u a l i t y a n d t h e i n t e r a c t i o n s b e t w e e n t h e s e p a r a m e t e r s a n d l a n d u s e . T h e f o l l o w i n g s e c t i o n i s a d i s c u s s i o n a b o u t i n t e r a c t i o n s b e t w e e n g r o u n d w a t e r a n d s u r f a c e w a t e r . T h e f i n a l s e c t i o n o f a n a l y s i s l o o k s at t h e r e s u l t s o f t h e o p i n i o n s u r v e y a n d t h e r e l a t i o n s h i p s b e t w e e n p e r c e p t i o n s o f w a t e r q u a l i t y a n d t h e p h y s i c a l p a r a m e t e r s tha t w e r e m e a s u r e d a s w e l l a s r e g i o n a l d i f f e r e n c e i n t h e s u r v e y r e s p o n s e s . 4.1 Groundwater Quality T w e n t y - s i x w a t e r q u a l i t y p a r a m e t e r s w e r e m e a s u r e d f o r e a c h s a m p l e o f g r o u n d w a t e r t a k e n . O f t h e s e , 2 1 w e r e e l e m e n t s m e a s u r e d u s i n g t h e I C P ( s e e s e c t i o n 3 . 1 . 3 f o r t h e c o m p l e t e l i s t o f e l e m e n t s m e a s u r e d ) . O n l y 13 o f t h e s e e l e m e n t s w e r e f o u n d a b o v e t h e m e t h o d d e t e c t i o n c o n c e n t r a t i o n ( M D C ) i n a n y o f t h e s a m p l e s . D u e t o c h a n g e s i n a n a l y t i c a l p r o c e d u r e t h e d e t e c t i o n l i m i t s v a r i e d b e t w e e n w i n t e r a n d s u m m e r s a m p l i n g f o r a n u m b e r o f e l e m e n t s . I n s o m e c a s e s t h i s d r a s t i c a l l y c h a n g e d t h e n u m b e r o f s a m p l e s a b o v e t h e d e t e c t i o n l i m i t . T a b l e 8 o u t l i n e s t h e s u m m a r y s t a t i s t i c s f o r a l l p a r a m e t e r s t ha t h a d at l e a s t o n e s a m p l e i n w i n t e r o r s u m m e r a b o v e t h e M D C . T h e m e a n , m e d i a n , s t a n d a r d d e v i a t i o n , m a x i m u m a n d m i n i m u m r e c o r d e d v a l u e as w e l l as t h e d e t e c t i o n l i m i t a n d t h e n u m b e r a n d p e r c e n t a g e o f s a m p l e s t ha t w e r e a b o v e t h e d e t e c t i o n l i m i t a r e l i s t e d . D u e t o a n e q u i p m e n t p r o b l e m w i t h t h e L a c h a t t h e w i n t e r s a m p l e s f o r o r t h o p h o s p h a t e w e r e i n v a l i d , t h e r e f o r e o n l y t h e J u l y P 0 4 d a t a w i l l b e u s e d . A l u m i n i u m , b a r i u m a n d b o r o n c o n c e n t r a t i o n s w e r e p r e d o m i n a n t l y b e l o w t h e d e t e c t i o n l i m i t a n d a r e t h e r e f o r e e x c l u d e d f r o m t h e a n a l y s i s . 44 Table 8. Groundwater Sampling Results: Summary Statistics for Each Variable with at Least One Sample above the Detection Limit (MDC)b MDC b # Above % Above Standard Element (mg/L) detection detection Mean Median Max Min Deviation E C _ S a c N/A 76 100% 217 115 3200 30 503.0 EC_W N/A 75 100% 219 123 3290 17 515.2 pH_Sa N/A 76 100% 6.68 6.40 8.35 5.82 0.693 pH_W N/A 75 100% 6.69 6.37 9.03 5.73 0.79 P04_S 0.050 56 74% 0.167 0.084 0.542 0.050 0.142 P04 W Orthophosphate results in winter were inaccurate due to analytical problems. N03_S 0.050 61 80% 0.938 0.362 10.129 0.050 1.60 N03_W 0.050 60 80% 1.242 0.498 11.962 0.050 1.973 NH3_S 0.050 8 10% 0.076 0.050 0.988 0.050 0.132 NH3_W 0.050 26 35% 0.068 0.050 0.826 0.050 0.091 A1_S 0.1000 0 0% - - - - -A1_W 0.050 2 2.7% 0.050 0.050 0.076 0.050 0.003 B_S 0.100 5 6.6% 0.183 0.100 3.704 0.467 B W 0.010 7 9.3% 0.106 0.014 3.366 0.010 0.439 Ba_S 0.5000 0 0.0% - - - - -Ba_W 0.010 20 27% 0.013 0.010 0.052 0.010 0.0086 Ca_S 0.50 75 99% 15.40 12.28 183.76 0.50 21.923 Ca_W 0.10 75 100% 14.04 11.65 200.20 0.13 23.378 Cu_S 0.025 36 47% 0.076 0.025 0.708 0.025 0.117 Cu_W 0.050 20 27% 0.096 0.050 1.388 0.050 0.176 Fe_S 0.200 10 13% 0.251 0.200 1.155 0.200 0.170 Fe_W 0.050 20 27% 0.150 0.050 2.175 0.050 0.3229 K_S 0.10 73 96% 1.33 0.49 18.72 0.10 2.801 K_W 0.50 34 45% 1.36 0.50 - 16.89 0.50 2.55 Mg_S 0.025 75 99% 4.845 2.761 31.377 0.025 5.960 Mg_W 0.010 75 100% 4.445 2.740 28.581 0.091 5.248 Mn_S 0.050 10 13% 0.070 0.050 0.718 0.050 0.086 Mn_W 0.005 31 41% 0.029 0.005 0.352 0.005 0.06 Na_S 1.000 75 99% 23.778 4.018 588.915 1.000 88.633 Na_W 0.250 68 91% 21.003 2.665 573.931 0.250 82.48 Si_S 0.500 76 100% 8.650 7.714 19.125 2.517 3.900 Si_W 0.150 75 100% 8.034 7.072 19.676 1.813 3.978 Sr_S 0.002 58 76% 0.074 0.047 0.850 0.020 0.104 Sr_W 0.002 73 97% 0.060 0.038 0.802 0.002 0.099 Zn_S 0.200 5 6.6% 0.336 0.200 6.677 0.200 0.803 Zn W 0.010 33 44% 0.153 0.010 3.338 0.010 0.551 a = all parameters are measured in mg/L with the exception of Conductivity which was measured in uS/cm and pH which was measured in pH units b = Method Detection Concentration (detection limit) c = _S = results for samples taken in summer (July 28, 2002) (n= 76) _W = results for samples taken in winter (March 10, 2003) (n=75) 45 4.1.1 Parameters exceeding the Guidelines for Canadian Drinking Water Quality S o m e w e l l s e x c e e d e d t h e G u i d e l i n e s f o r C a n a d i a n D r i n k i n g W a t e r Q u a l i t y ( G C D W Q ) f o r o n e o r m o r e p a r a m e t e r . T a b l e 9 o u t l i n e s t h e m a x i m u m a l l o w a b l e c o n c e n t r a t i o n ( M A C ) f o r t h e s e p a r a m e t e r s a n d t h e n u m b e r o f w e l l s i n e a c h s a m p l i n g p e r i o d t ha t e x c e e d e d t h e g u i d e l i n e s . F o r t h e p u r p o s e o f c o m p a r i s o n , t a b l e 2 i n c h a p t e r 1 o u t l i n e s t h e n u m b e r o f e x c e e d a n c e s o f t he s a m e e l e m e n t s f r o m a p r e v i o u s s t u d y t ha t l o o k e d at w a t e r q u a l i t y o f c o m m u n i t y w e l l s t h r o u g h o u t t h e L o w e r F r a s e r V a l l e y ( C a r m i c h a e l et al., 1 9 9 5 ) . Table 9. Number of wells exceeding the Guidelines for Canadian Drinking Water Quality, Hatzic Valley Sampling, 2002, 2003 Parameter MAC (GCDWQ) # Winter n=75 # Summer n=7 6 Iron (Fe) 0.3 mg/L 8 (10%) 8 (10%) Copper (Cu) 1 mg/L 1 (1.3%) -Zinc (Zn) 5 mg/L - 1 (1.3%) Manganese (Mn) 0.05 mg/L 10 (13.5%) 10 (13.5%) Sodium (Na) 200 mg/L 2 (2.7%) 2 (2.7%) PH 6.5-8.5 pH units 47 (63%) . 45(60%) Nitrate-N (N03-N) 10 mg/L 1 (1.3%) 1 (1.3%) GCDWQ = Guidelines for Canadian Drinking Water Quality MAC = Maximum Allowable Concentration 4.1.1a pH T h e m o s t c o m m o n e x c e e d a n c e i n t he s t u d y a r e a w a s p H ; a p p r o x i m a t e l y 6 0 % ( 4 7 w e l l s i n w i n t e r a n d 4 5 w e l l s i n s u m m e r ) o f t h e w e l l s s a m p l e d h a d p H b e l o w 6 . 5 . L o w g r o u n d w a t e r p H i n t h e L F V h a d b e e n n o t e d i n p r e v i o u s r e p o r t s ( D a k i n , 1 9 9 4 a n d C a r m i c h a e l et al., 1 9 9 5 ) . T h e l o w p H i s l i k e l y d u e t o t he g r a n i t i c b e d r o c k t h a t m a k e s u p a l a r g e p a r t o f t h e H a t z i c w a t e r s h e d . G r a n i t e s u b s t r a t e s a r e a c o m m o n c a u s e o f a c i d i c w a t e r s . L o w p H i n i t s e l f i s n o t a h e a l t h c o n c e r n b u t w a t e r w i t h l o w p H c a n c a u s e e n h a n c e d c o r r o s i o n o f m e t a l i n p i p e s ( e s p . c o p p e r ) o r i n t h e s u b s t r a t e ( i r o n a n d m a n g a n e s e ) , w h i c h c a n t h e n l e a d t o e l e v a t e d l e v e l s o f m e t a l i n w a t e r ( L e i t c h , 2 0 0 0 ) . 4.1.1b Metals E i g h t e x c e e d a n c e s o f i r o n a n d 10 o f m a n g a n e s e w e r e r e c o r d e d f o r w e l l s s p r e a d t h r o u g h o u t t h e w a t e r s h e d ( s e e f i g . 1 4 ) . C o n v e r s a t i o n s w i t h w e l l o w n e r s s u g g e s t e d t ha t h i g h i r o n i s a k n o w n p r o b l e m f o r p e o p l e w h o h a v e d r i l l e d w e l l s i n t o A Q 2 a c c o u n t i n g f o r t h e h i g h u s e o f s u r f a c e w a t e r f o r d o m e s t i c c o n s u m p t i o n i n t h i s a r e a . B a s e d o n t h e s a m p l i n g r e s u l t s , h o w e v e r , a l l a r e a s s e e m e d e q u a l l y p r o n e t o h i g h i r o n a n d m a n g a n e s e l e v e l s w i t h n o i m m e d i a t e l y e v i d e n t s p a t i a l t r e n d s ( e x c e p t t ha t t h e r e w e r e n o e x c e e d a n c e s o n H a t z i c I s l a n d ) . T h e a q u i f e r c l a s s i f i c a t i o n r e p o r t ( K r e y e a n d W e i , 1 9 9 4 ) d i d n o t m e n t i o n h i g h i r o n a s b e i n g a p r o b l e m i n A Q 3 ; h o w e v e r , I f o u n d tha t 4 o f 8 i r o n e x c e e d a n c e s a n d 3 o f 1 0 m a n g a n e s e e x c e e d a n c e s w e r e i n w e l l s o n t h i s a q u i f e r , s u g g e s t i n g t ha t t h e r e i s t h e s a m e p o t e n t i a l f o r h i g h i r o n t o o c c u r h e r e as i n t h e o t h e r t w o a q u i f e r s . A s m e n t i o n e d i n t h e i n t r o d u c t i o n , i r o n a n d m a n g a n e s e l e v e l s a r e 46 g e n e r a l l y r e l a t e d t o t h e s u b s t r a t e t h r o u g h w h i c h w a t e r f l o w s b e f o r e r e a c h i n g t h e w e l l a n d n o t f r o m a n t h r o p o g e n i c i n f l u e n c e . I n a d d i t i o n t o t h e e x c e e d a n c e s o f i r o n a n d m a n g a n e s e , o n e w e l l h a d c o p p e r a b o v e t h e C G D W Q a n d o n e h a d z i n c a b o v e t h e l i m i t . C o r r o d i n g p i p e s h a v e b e e n i d e n t i f i e d a s t h e m o s t p r o b a b l e s o u r c e o f e l e v a t e d l e v e l s o f C u a n d Z n i n g r o u n d w a t e r i n t h e L o w e r F r a s e r V a l l e y ( C a r m i c h a e l et al, 1 9 9 5 ) . It i s n o t s u r p r i s i n g t ha t a f e w h o m e s i n t h e v a l l e y h a v e h i g h c o p p e r a n d z i n c b a s e d o n t h e l o w p H o f t h e w a t e r i n t h e a r e a . Iron (mg/L) • 0.05-0.3 O 0.3-3 Manganese (mg/L) . 0.005 - 0.05, -fc 0.05-0.4 IHM! Lake • Roads A 1 9 7 9 s t u d y e n t i t l e d " a N a t i o n a l S u r v e y f o r C d , C r , C u , P b , Z n , C a a n d M g i n C a n a d i a n D r i n k i n g W a t e r S u p p l i e s " s a m p l e d t h e p r e v i o u s l y m e n t i o n e d e l e m e n t s i n s u r f a c e a n d w e l l w a t e r a c r o s s C a n a d a ( M e r a n g e r et al., 1 9 7 9 ) . I n t h i s s t u d y C u a n d Z n l e v e l s w e r e c o n s i s t e n t l y h i g h e r i n d i s t r i b u t e d w a t e r t h a n i n r a w w a t e r ( d u e t o c o r r o s i o n o f p i p e s ) . W e c a n c o m p a r e t h e m a x i m u m v a l u e s f o r u n t r e a t e d w a t e r i n t h e 1 9 7 9 s t u d y f o r C u , Z n , C a a n d M g t o t h e m a x i m u m c o n c e n t r a t i o n s o f t h e s a m e e l e m e n t s m e a s u r e d i n t h e H a t z i c w a t e r s h e d s t u d y ( o f t h e m e t a l s m e a s u r e d i n t h e 1 9 7 9 s t u d y t h e s e w e r e t h e o n l y o n e s i n t h e p r e s e n t s t u d y a b o v e t h e d e t e c t i o n l i m i t ) . S o m e s a m p l e s f r o m t h e H a t z i c V a l l e y h a d v a l u e s f o r C u , Z n a n d C a t ha t g r e a t l y e x c e e d e d t h e h i g h e s t l e v e l r e c o r d e d i n t h e 1 9 7 9 s t u d y ( s e e t a b l e 1 0 ) . T h i s i s l i k e l y b e c a u s e t h e s t u d y s a m p l e d c o m m u n i t y d r i n k i n g w a t e r s u p p l i e s r a t h e r t h a n p r i v a t e w e l l s . C o m m u n i t i e s o f t e n h a v e m o r e c h o i c e a b o u t w h i c h w a t e r s u p p l i e s t o d e v e l o p t h a n p r i v a t e w e l l o w n e r s ; a m u n i c i p a l i t y m a y b e a b l e t o r e j e c t w a t e r s u p p l i e s w i t h h i g h m e t a l s i n f a v o u r o f a n o t h e r s i t e , o r d r i l l a d e e p e r w e l l t o a c c e s s a n a q u i f e r w i t h b e t t e r w a t e r q u a l i t y w h e r e a s a p r i v a t e w e l l o w n e r i s l i m i t e d t o t h e w a t e r t ha t i s a v a i l a b l e o n t h e i r o w n p r o p e r t y a n d m a y n o t b e a b l e t o a f f o r d t o d r i l l a d e e p e r w e l l . 1 6 4 Kilometers Figure 14. Wells exceeding the CGDWQ for Fe and Mn V 47 Table 10. Comparison of maximum Cu, Zn, Ca and Mg levels in Hatzic Valley with results of Meranger et al, 1979 Element" Max DW (1979 study) Max RW (1979 study) Max Hatzic Valley Summer Max Hatzic Valley Winter Number of Hatzic Samples above 1979 maximum Cu 0.260 0.11 1.388 0.7079 3 Zn 0.130 0.02 3.33 6.67 9 Ca 70.1 67.6 200 183.1 1 Mg 54.7 81.7 28.5 31.3 0 a = all values are given in mg/L DW= Distributed Well Water RW = Raw Well Water 4.1.2 Conductivity C o n d u c t i v i t y h a d t h e g r e a t e s t r a n g e o f a l l p a r a m e t e r s m e a s u r e d . V a l u e s c o v e r e d t h r e e o r d e r s o f m a g n i t u d e f r o m 17 u S / c m t o 3 2 9 0 u S / c m . T h e v a l u e s w e r e n o t e v e n l y d i s t r i b u t e d i n t h i s r a n g e a n d o n l y s i x s a m p l e s ( 8 % ) h a d v a l u e s a b o v e 3 0 0 u S / c m ( s e e t a b l e 1 1 ) . F i g u r e 15 c l e a r l y s h o w s h o w m u c h h i g h e r t h e s e v a l u e s a r e t h a n t h e m a j o r i t y o f c o n d u c t i v i t y v a l u e a n d f i g u r e 16 s h o w s t h e c o n d u c t i v i t y p l o t s w i t h t h e s i x o u t l i e r s r e m o v e d . Table 11. High conductivity wells Conductivity pS/cm Sodium mg/L Well Number Aquifer Winter Summer Winter Summer Depth of Well 26 AQ2 3290 3200 422.13 497.25 91.44 (artesian) 77 AQ2 3100 3100 573.93 588.91 Unknown (artesian) 42 AQ2 1030 1000 121.008 137.61 60.96 40 AQ2 • 610 550 80.75 99.55 60.96 (artesian) 25 AQl 390 410 27.42 31.80 7.62 45 AQ3 340 330 6.52 8.55 19.20 I n t h e L o w e r F r a s e r V a l l e y t h e r e a r e d e e p r e g i o n a l s a l i n e a q u i f e r s u n d e r l y i n g m a n y o f t h e i d e n t i f i e d a q u i f e r s ( C a r m i c h a e l et al., 1 9 9 5 ) . T h e w a t e r f r o m w e l l s 2 6 , 7 7 , 4 0 a n d 4 2 ( w h i c h a r e a l l l o c a t e d o n A Q 2 ) a r e l i k e l y f r o m t h i s d e e p r e g i o n a l a q u i f e r ( s e e t h e s o d i u m l e v e l s a n d d e p t h s p r e s e n t e d i n t a b l e 9 ) . T h r e e o u t o f f o u r o f t h e s e w e l l s a r e k n o w n t o b e f l o w i n g a r t e s i a n w e l l s a n d a r e a m o n g t h e d e e p e s t w e l l s s a m p l e d . T h e r e a r e t w o w e l l s s a m p l e d w h i c h a r e d e e p e r t h a n w e l l 2 6 t h a t d o n o t h a v e a b n o r m a l l y h i g h c o n d u c t i v i t y o r s o d i u m l e v e l s , h o w e v e r t h e s e w e l l s a re l o c a t e d at s e v e r a l h u n d r e d m e t r e s h i g h e r e l e v a t i o n t h a n w e l l 2 6 a n d i f t h e d e p t h s w e r e c o r r e c t e d f o r e l e v a t i o n i t i s l i k e l y t ha t w e l l s 2 6 , 7 7 , 4 0 a n d 4 2 w o u l d b e d e e p e r o n a n a b s o l u t e s c a l e . W e l l s 2 5 a n d 4 5 d o n o t f i t t h e s a m e p a t t e r n a s t h e o t h e r f o u r h i g h c o n d u c t i v i t y w e l l s , t h e y a r e n o t e x t r a d e e p n o r t o t h e y h a v e e x t r a o r d i n a r i l y h i g h s o d i u m l e v e l s . T h e h i g h c o n d u c t i v i t y l e v e l s o f t h e s e w e l l s a r e t h e r e f o r e d u e t o d i f f e r e n t f a c t o r s . 48 Figure 16 also shows that in general, once these six outliers are removed, the wells on aquifer one have higher conductivity values than those in AQ2 and AQ3 (the conductivity values of AQl are significantly (a = 0.05) different than those of AQ3, the difference between AQl and AQ2 and AQ2 and AQ3 were not significantly different from each other). E u CO >» 4000 3000 2000 1000 u 3 T3 C o o $9 m |—[Winter g S u m m e r *42 «42 0*0 ^to = 22 22 20 20 30 30 AQ1 AQ2 AQ3 Figure 15. Boxplots of conductivity showing outliers 300 200 E o ^100 I 0 o 3 •o C o O N | | Winter I—| S u m m e r rJ8 CJ5 X 21 21 AQ1 16 16 AQ2 C£3 29 29 AQ3 Figure 16. Boxplots of Conductivity, outliers (wells 26, 77, 42, 40, 25, 45) removed 4.1.5 Orthophosphate: P04 The orthophosphate results were surprising because they showed very strong regional variation. The highest levels of P0 4 were found in wells on Hatzic Island. These were significantly higher (a = 0.05) than the wells from the area just east of the island and higher again that those found on AQ2 and AQ3 (the P0 4 levels in AQ2 and AQ3 were not significantly different from each other). The results are worth mention because P0 4 is generally considered to be a parameter, like nitrate, for which the levels are determined by land use. The pattern seen in Hatzic suggests that the levels of P0 4 are influenced by different process than the nitrate levels. Several theories can be suggested to explain the observed pattern. Hatzic Island has the densest concentration of homes in the study area and each of these homes is on a septic system. Some studies have suggested that septic systems can release significant quantities of P0 4 into the subsurface. While the source of P0 4 may be from septic systems it must be kept in mind that all of the wells sampled on Hatzic Island had higher levels of P0 4 than the other areas of the valley but not all the wells sampled (even on Hatzic Island) were located in densely populated areas. The elevated P0 4 levels are seen consistently across the region. 49 0.101 I • I Hatzic East of AQ2 Island Hatzic Island AQ3 Figure 17. Boxplot of P0 4 grouped by aquifer (aquifer 1 split into two groups, Hatzic Island and area east of Hatzic island) The water table on Hatzic Island is quite high and interaction between groundwater and water from Hatzic Lake would seem to be inevitable. No water quality data for Hatzic Lake was collected during this study but previous research from as far back as 1973 suggests that eutrophication has been a concern in this body of water for some time (Drinnan, 1975). All of the values of P04 measured in wells on Hatzic Island are above the levels considered to be of concern for eutrophication of streams or lakes (0.01 mg/L P level is often used as a standard for the prevention of lake eutrophication (Schreier et al, 1996)). Since the flow and interaction between Hatzic Lake water and groundwater is not known it is difficult to determine if eutrophic lake water may be influencing the groundwater P04 or if the interaction is in reverse with the groundwater impacting the lake. Likely the relationship is both ways, when the water table is high, the septic systems on the island may not be able to function correctly, releasing P04 to the subsurface and to the lake; however, if the lake water is already mesotrophic or eutrophic, phosphorus rich water could be impacting the groundwater. The relationship with phosphorus is further complicated but the fact that large portions of the lake bottom are exposed during parts of the year. Decomposition of organic matter during periods of low water could cause releases of phosphorus to the lake when the lake floods again. It is known that large powerboats are continually stirring up sediments in the lake bottom, which could lead to continual re-suspension of phosphorus rich sediments. The highest levels of P04 on AQ2 are from the three deepest wells, 75, 77 and 40, (the same wells with very high conductivity) suggesting that in this case geological processes are determining levels of this nutrient (Eyre and Pepperell, 1999). Further research would have to be done on Hatzic Island to 50 d e t e r m i n e t h e i n t e r a c t i o n s b e t w e e n H a t z i c L a k e w a t e r a n d t h e g r o u n d w a t e r o n t h e i s l a n d a n d h o w t h e s e t w o s y s t e m s i n f l u e n c e t h e l e v e l s o f P 0 4 , w h i c h , i f t h e g r o u n d w a t e r f r o m t h e i s l a n d i s d i s c h a r g i n g i n t o t h e l a k e a r e h i g h e n o u g h t o c a u s e s e r i o u s c o n c e r n a b o u t e u t r o p h i c a t i o n . 4.1.2 Nitrate-N (N03-N) T h e G u i d e l i n e f o r C a n a d i a n D r i n k i n g W a t e r Q u a l i t y f o r n i t r a t e - N i s 1 0 m g / 1 ( t h e l e v e l i s 4 5 m g / L i f r e p o r t e d as n i t r a t e ( N 0 3 - ) ) , h o w e v e r , l e v e l s a b o v e 3 m g / L a r e c o n s i d e r e d t o b e i n d i c a t i v e o f g r o u n d w a t e r t ha t i s u n d e r t h e i n f l u e n c e o f s u r f a c e w a t e r ( C a r m i c h a e l et al., 1 9 9 5 ; S c h r e i e r et al., 1996,) . T a b l e 12 s h o w s t h e w e l l s w i t h n i t r a t e - N v a l u e s a b o v e 3 m g / L d u r i n g a t l e a s t o n e o f t h e s a m p l i n g p e r i o d s . W e l l s w i t h n i t r a t e - N a b o v e 4 m g / L w e r e r e - s a m p l e d ( w i t h i n 2 w e e k s i n t h e s u m m e r a n d w i t h i n a m o n t h i n t he w i n t e r ) a n d t h e s e v a l u e s a r e p r e s e n t e d i n b r a c k e t s b e s i d e t h e o r i g i n a l . S i x w e l l s h a d h i g h e r n i t r a t e v a l u e s i n w i n t e r t h a n i n s u m m e r a n d f i v e w e l l s s h o w e d t h e r e v e r s e t r e n d . T h e w e l l w i t h t h e g r e a t e s t c h a n g e i n n i t r a t e - N v a l u e w a s w e l l 1 1 , w h i c h s h o w e d a 7 . 4 m g / L i n c r e a s e b e t w e e n s u m m e r a n d w i n t e r . Table 12. Samples with Nitrate-N values above 3 mg/L in at least one sampling. Well Number N03-N-Wintera N03-N-Summer Change Depth (m) 1 3.008 1.003 2.005 9.45 5 3.075 4.828 (4.624) -1.753 7.01 6 4.933 (3.793) 5.286 (5.325) -0.353 6.10 11 11.962* (12.131) 4.538 (2.093) 7.424 N.A. 12 3.369 4.705 (7.06) -1.336 7.62 15 2.168 3.284 -1.116 N.A. 16 5.307 (6.813) 0.579 4.728 9.14 19 7.499 (6.251) 10.129* (9.240) -2.63 4.27 43 3.447 3.141 0.306 5.49 58 4.061 (4.296) 2.784 1.277 7.62 79 6.111 (2.973) 0.901 5.209 0.91 81 3.141 N/A N/A N/A a - all nitrate-N values, including "change" are in mg/L * Bold values are above the GCDWQ. ( ) re-sampled nitrate level N/A = data not available B o t h t h e w e l l s w i t h n i t r a t e l e v e l s a b o v e 1 0 m g / 1 w e r e l o c a t e d o n t h e N i c o m e n s l o u g h a q u i f e r as w e r e t h e v a s t m a j o r i t y o f t h e s a m p l e s t ha t m e a s u r e d a b o v e t h r e e . P r e v i o u s r e s e a r c h o n g r o u n d w a t e r q u a l i t y i n t h e L o w e r F r a s e r V a l l e y f o u n d n o n i t r a t e v a l u e s a b o v e 10 m g / L i n w e l l s l o c a t e d o n t h e N i c o m e n s l o u g h a q u i f e r . T h i s s t u d y o n l y e x a m i n e d c o m m u n i t y w e l l s a n d a c k n o w l e d g e d t ha t p r i v a t e w e l l s a r e m o r e l i k e l y t o b e c o n t a m i n a t e d t h a n c o m m u n i t y w e l l s ( C a r m i c h a e l et al., 1 9 9 5 ) . T h e t h r e e w e l l s t ha t w e r e n o t o n t h e N i c o m e n s l o u g h tha t h a d n i t r a t e a b o v e t h r e e w e r e a l s o v e r y s h a l l o w ( 5 . 4 9 m , 7 . 6 2 m , a n d 0 . 9 1 m ) . I n t h e s u m m e r , w e l l 19 ( l o c a t e d o n t h e eas t o f H a t z i c I s l a n d ) w a s t h e o n l y w e l l t h a t e x c e e d e d t h e g u i d e l i n e f o r n i t r a t e ( 1 0 . 1 3 m g / L ) . I n o r d e r t o t r y a n d d e t e r m i n e t h e e x t e n t o f t h e n i t r a t e p r o b l e m a r o u n d 51 well 19, three additional wells were sampled as part of the March sampling. In March the nitrate level in well 19 had dropped to 7.5 mg/L, below the health standards but still well above background levels. Of the additional wells sampled well 81, had a nitrate level of 3.14 mg/L while the other two wells, which were slightly farther away had levels below 3 mg/L (1.8 mg/L and 0.9 mg/L). This suggests that the nitrate contamination seen in well 19 may be also impacting well 81 but that the problem is not widespread as the levels of nitrate dropped quickly as one moved away from this well. The highest nitrate value was seen in the winter in well 11 (11.96 mg/L) This well (which is located in a small rural subdivision on Hatzic Island) did not exceed drinking water quality guidelines in the summer, however both well 11 and well 12 (located next door) had nitrate levels above 3 mg/L in both winter and summer suggesting there may be a more widespread nitrate pollution problem in this area. Seasonal variations in nitrate level do not appear to follow a consistent pattern. There were more wells in the winter that had nitrate values above 3 mg/L, however the well with the highest nitrate in the summer decreased substantially in the winter. In the summer there were more wells on Hatzic Island with nitrate levels above 3. The nitrate values in some of these wells decreased in the winter while others remained fairly constant. In the winter high nitrate values were found throughout a wider area in the valley. This is consistent with previous research that has found that nitrate levels tend to vary with the season but that there is no discernable trend in that variation that can be related to a specific season (Carmichael et al, 1995; Liebscher et al, 1992). 4.1.4 Coliforms Groundwater samples that measured above 4 mg/L nitrate were re-sampled to confirm the N O 3 - N value as well as being sent to the British Columbia Centre for Disease Control (BCCDC) for bacterial testing (total and fecal coliforms). The results of the coliform analysis can be found in table 13. None of the samples from Hatzic Island, which had the highest nitrate values, had any detectable coliforms in the water. Total coliforms were detected in the winter in one well on AQ2 and one on AQ3. Both of these wells were very shallow and were located in areas with livestock close by. Well 58 appears, based on the airphotos, to be located in a forest and have no agricultural or urban land use nearby which makes the high nitrate and coliform values seem to be anomalous, however upon visiting the property it was observed that there was livestock such as sheep and chickens freely wandering the property which could be a source for nitrate and coliforms. The highest levels of total coliforms were found in the summer in well 76, which did not have a nitrate problem (the nitrate levels were below the detection limit in this well). However the owner informed us that this well had significant structural problems that likely led to the coliform contamination. This well was also quite shallow (2.74 m) suggesting that that depth may also be a significant factor in determining coliform contamination. 52 Table 13. Nitrate Values and Coliform Well Number Winter Summer Total coliforms count/100 ml Fecal coliforms count/100 ml Nitrate Total coliforms count/100 ml Fecal coliforms count/100 ml Nitrate 5 - - - L I L I 4.83 6 L I L I 4.9 L I L I 5.28 10 - - - L I L I 4.54 11 L I L I 11.96 L I L I 4.71 16 L I L I 5.30 - - -19 L I L I 7.5 L I L I 10.13 58 12 1 4.06 - - -79 4 1 6.11 * • - -76 1 L I O.05 EST 200 L I <0.05 L = l e s s t h a n EST = h i g h c o l o n y d e n s i t y o n m e m b r a n e p r e v e n t i n g a c c u r a t e c o l i f o r m c o u n t i n g - = w e l l n o t t e s t e d f o r c o l i f o r m s 4.2 Parameter Interactions T h e p r e c e d i n g s e c t i o n h a s d i s c u s s e d g r o u n d w a t e r q u a l i t y i n t h e H a t z i c V a l l e y i n t e r m s o f t h e l e v e l s o f i n d i v i d u a l w a t e r q u a l i t y p a r a m e t e r s . T h e f o l l o w i n g s e c t i o n s w i l l l o o k a t r e l a t i o n s h i p s b e t w e e n w a t e r q u a l i t y p a r a m e t e r s a n d b e t w e e n t h e s e p a r a m e t e r s a n d o t h e r i n f l u e n c i n g f a c t o r s . T h e g o a l o f t h i s p r o j e c t i s t o g a i n a b e t t e r u n d e r s t a n d i n g o f l a n d - u s e i m p a c t s o n w a t e r q u a l i t y a n d i n o r d e r t o d o t h i s i t m u s t b e d e t e r m i n e d i f t h e d i f f e r e n c e i n l e v e l s o f t h e w a t e r q u a l i t y v a r i a b l e s a r e p r i m a r i l y d u e t o g e o l o g y o r d u e t o a n t h r o p o g e n i c f a c t o r s . B y e x a m i n i n g t h e w a y t h e v a r i a b l e s c h a n g e w i t h s e a s o n , d e p t h a n d t h e c o r r e l a t i o n s b e t w e e n t h e m , a b e t t e r u n d e r s t a n d i n g o f t h e d o m i n a n t i n f l u e n c e o n e a c h s h o u l d b e g a i n e d a l l o w i n g t h e m t o b e c a t e g o r i z e d a s b e i n g e i t h e r l a r g e l y i n f l u e n c e d b y g e o l o g y o r i n f l u e n c e d b y l a n d u s e . 4.2.1 Seasonal Variation G r o u n d w a t e r s a m p l e s w e r e t a k e n i n w i n t e r a n d i n s u m m e r ( M a r c h a n d J u l y r e s p e c t i v e l y ) t o a s s e s s s e a s o n a l d i f f e r e n c e s i n g r o u n d w a t e r q u a l i t y . W e w o u l d o n l y e x p e c t t o s e e s i g n i f i c a n t d i f f e r e n c e s i n w a t e r q u a l i t y i f t h e g r o u n d w a t e r w a s u n d e r t h e i n f l u e n c e o f s u r f a c e w a t e r . P a r a m e t e r l e v e l s f o r a l l w e l l s t ha t w e r e s a m p l e d t w i c e w e r e c o m p a r e d ( t h e r e w e r e 7 w e l l s t ha t w e r e n o t s a m p l e d t w i c e l e a v i n g 72 w e l l s f o r c o m p a r i s o n ) . S p e a r m a n ' s r a n k c o r r e l a t i o n c o e f f i c i e n t s s h o w e d a s i g n i f i c a n t c o r r e l a t i o n b e t w e e n t h e w i n t e r a n d s u m m e r v a l u e s o f e a c h p a r a m e t e r . T h e s e c o r r e l a t i o n s a r e l i s t e d i n t a b l e 14. T o f u r t h e r tes t i f t h e r e w e r e a n y s e a s o n a l d i f f e r e n c e s i n g r o u n d w a t e r q u a l i t y t h e M a n n - W h i t n e y U t es t w a s r u n t o c o m p a r e r e s u l t s f o r e a c h s e a s o n . 53 The results of the analysis, also outlined in table 14 show that most seasonal differences can be explained by inconsistencies in the analysis. The detection limit for many of the parameters changed between the summer and winter sampling as the laboratory staff became more familiar with equipment that was new when the summer samples were taken. The changes in detection limit led to a situation in which the number of samples above the detection limit changed quite dramatically between winter and summer for some parameters. The detection limits can be found in table 8 in section 4.1. The second column of table 14, "change in MDC" shows the difference in percentage of samples that were above the detection limit. For example, potassium (K) had 96% of samples above the detection limit in the summer but because the detection limit changed from 0.1 to 0.5 only 46% of samples registered above the detection limit in the winter. This gives a difference of 51%. When the Mann-Whitney test was re-run on the data with all samples below the highest detection limit removed there were far fewer parameters that showed a significant difference in value between summer and winter. Table 14. Results of seasonal analysis Parameter % Change i n # o f samples above detection l imi t Cor re la t ion coeff ic ient* (Win ter vs. Summer) Aquifer 1 Aquifer 2 Aquifer 3 A i l aquifers A l l d a t a B e l o w M D C r e m o v e d All d a t a B e l o w M D C r e m o v e d All d a t a B e l o w M D C r e m o v e d All d a t a B e l o w M D C r e m o v e d EC 0% 0.935 PH 0% 0.893 N H 3 25% 0.471 *• ** ** ** N 0 3 - N 0% 0.924 Ca 1% 0.954 Cu 20% 0.620 ** ** ** Fe 14% 0.704 ** ** ** ** K 51% 0.804 ** ** M g 1% 0.989 M n 28% 0.613 ** ** ** Na 8% 0.950 ** ** ** ** Si 0% 0.982 Sr 21% 0.965 ** ** Zn 37% 0.478 #* ** ** ** ** = There is a significant difference between the medians based on the Mann-Whitney U test a = A l l correlations (r) were significant at 0.01 level (2-tailed) 4.2.2 Parameter Correlation The preceding sections have outlined patterns seen in water quality when individual characteristics were examined. Section 4.2.1 showed that there is little significant seasonal variation in water quality. This section examines the interactions between parameters. There were significant correlations between many of the parameters that are displayed in table 14. Those that are significantly correlated with each other are shown in table 15. The high correlations were mainly seen in parameters that had most values above the detection limit. The correlations between parameters indicate those that are influenced by similar 54 p r o c e s s e s . N i t r a t e - N l e v e l s w e r e n o t s i g n i f i c a n t l y c o r r e l a t e d w i t h a n y o f t h e v a r i a b l e s i n t a b l e 15 s u g g e s t i n g t h a t d i f f e r e n t p r o c e s s e s d e t e r m i n e w h a t t h e l e v e l s o f N O 3 - N w i l l b e . Table 15. Correlations between selected parameters (Spearman's Rank correlation coefficients (r)). Ca EC PO4 Sr Si Na Mg Ca 1 EC 0 . 8 1 6 1 P 0 4 0 . 6 7 1 0 . 7 6 8 1 Sr 0 . 8 5 1 0 . 7 7 5 0 . 7 2 2 1 Si 0 . 7 0 1 0 . 8 2 3 0 . 9 2 7 0 . 7 0 3 1 Na 0 . 6 2 4 0 . 8 6 9 0 . 6 1 8 0 . 5 9 7 0 . 6 8 3 1 Mg 0 . 8 9 5 0 . 8 1 4 0 . 7 8 2 0 . 8 7 8 0 . 8 0 2 0 . 6 1 5 1 A l l c o r r e l a t i o n s a r e s i g n i f i c a n t at 0 . 01 4.2.3 Depth S h a l l o w w e l l s i n u n c o n f i n e d a q u i f e r s h a v e l o n g b e e n k n o w n t o b e m o r e s u s c e p t i b l e t o c o n t a m i n a t i o n t h a n d e e p e r w e l l s . T h e r e f o r e , t h e d e p t h o f w e l l i s a n i m p o r t a n t d e t e r m i n a n t o f t h e v u l n e r a b i l i t y o f a p a r t i c u l a r w e l l t o c o n t a m i n a t i o n . I n t h e H a t z i c V a l l e y t h e r e a r e s i g n i f i c a n t d i f f e r e n c e s b e t w e e n t h e d e p t h s o f w e l l s i n A Q l a n d A Q 3 ( a = 0 . 0 5 ) ( F i g u r e 18 s h o w s t h e r e l a t i o n s h i p b e t w e e n d e p t h s i n t h e t h r e e a q u i f e r s ) . T h e w e l l s i n A Q l a r e s i g n i f i c a n t l y s h a l l o w e r t h a n t h o s e i n A Q 3 . T h e d i f f e r e n c e s i n d e p t h b e t w e e n A Q l & A Q 2 a n d A Q 2 & A Q 3 a r e n o t s i g n i f i c a n t . A Q 2 h a s t h e g r e a t e s t r a n g e o f d e p t h s b e c a u s e o f t h e d e e p w e l l s t ha t t a p i n t o a d e e p r e g i o n a l a q u i f e r ( s e e s e c t i o n 4 . 1 . 2 f o r f u r t h e r d i s c u s s i o n o f t h e s e w e l l s ) . AQ1 AQ2 A Q 3 Figure 18. Depth Boxplot (Division by Aquifer) S o m e s t u d i e s m e n t i o n a s t r o n g r e l a t i o n s h i p b e t w e e n n i t r a t e a n d d e p t h ( S c h r e i e r et al, 1 9 9 6 ; H u d a k , 1 9 9 9 ; B u r k a r t a n d S t o n e r , 2 0 0 2 ; M u h a m m e t o g l u et al, 2 0 0 2 ; R e i d et al, 2 0 0 2 ) . T h e r e s u l t s o f t h i s s t u d y s h o w tha t a l t h o u g h t h e r e a r e m a n y s h a l l o w w e l l s w i t h l o w n i t r a t e v a l u e s t h e r e a r e n o d e e p w e l l s w i t h n i t r a t e a b o v e 3 m g / 1 ( s e e f i g u r e 1 9 ) . A p r e v i o u s s t u d y i n t h e L F V f o u n d t ha t , " n i t r a t e - N w h e r e p r e s e n t i n w e l l s 55 g e n e r a l l y l e s s t h a n 6 0 m d e e p . T h i s t r e n d o f n i t r a t e - N w i t h d e p t h i n d i c a t e d t h a t t h e s o u r c e o f n i t r a t e - N i s r e l a t e d t o a c t i v i t i e s a t t h e l a n d s u r f a c e " ( C a r m i c h a e l et al, 1 9 9 5 ) . I n t h e p r e s e n t s t u d y a n e v e n m o r e Nitrate (mg/L) 5 10 15 Change in Nitrate-N (mg/L) -5.0 0.0 5.0 10.0 0 20 ? 40 s: Q. <D 60 O 80 100 - 1 # * ^ ® 1 -+-»+-o — t — ©AQ1 • AQ2 A AQ3 Figure 19. Nitrate vs. Depth (winter data) Figure 20. Seasonal Change in Nitrate vs. Depth c o n s e r v a t i v e d e p t h w a s f o u n d . T h e r e a r e n o w e l l s d e e p e r t h a n 12 m w i t h n i t r a t e l e v e l s a b o v e 3 m g / 1 . A l t h o u g h t h e r e w e r e h i g h c o r r e l a t i o n s b e t w e e n t he w i n t e r a n d s u m m e r s a m p l i n g f o r m o s t p a r a m e t e r s ( i n c l u d i n g N i t r a t e ) ( s e c t i o n 4 . 2 . 1 ) f i g u r e 2 0 s h o w s t h e i m p o r t a n c e o f d e p t h i n i n f l u e n c i n g t h e n i t r a t e v a l u e s i n t h e v a l l e y . N o w e l l s d e e p e r t h a n 12 m h a d s i g n i f i c a n t f l u c t u a t i o n s ( g r e a t e r t h a n 1 m g / L ) i n n i t r a t e v a l u e s b e t w e e n w i n t e r a n d s u m m e r h o w e v e r , s e v e r a l w e l l s t ha t w e r e s h a l l o w e r t h a n 12 m d i d . T h i s s u g g e s t s t ha t t h e s e s h a l l o w e r w e l l s a r e u n d e r t h e i n f l u e n c e o f s u r f a c e w a t e r a n d t h e r e f o r e l a n d u s e , w h e r e a s t h e d e e p e r w e l l s a r e n o t . T h e p a r a m e t e r s i n t a b l e 15 t ha t w e r e h i g h l y c o r r e l a t e d w i t h e a c h o t h e r d i d n o t s h o w t h e s a m e r e l a t i o n s h i p w i t h d e p t h as n i t r a t e d i d . R a t h e r t h a n b e i n g i n f l u e n c e d b y d e p t h i t i s l i k e l y s a f e t o a s s u m e t ha t t h e l e v e l s o f t h e s e p a r a m e t e r a r e d e p e n d e n t o n t h e g e o l o g y o f t h e s u b s t r a t e t h r o u g h w h i c h t h e y f l o w r a t h e r t h a n b y a n t h r o p o g e n i c i n f l u e n c e s . 4.3 Parameters Influenced by Geology I n t h i s s t u d y g r o u n d w a t e r s a m p l e s w e r e t a k e n f r o m t h r e e d i s t i n c t a q u i f e r s ; i t w a s t h e f i r s t s t u d y t o l o o k at t h e s e t h r e e a q u i f e r s as a s y s t e m . I n o r d e r t o f u r t h e r u n d e r s t a n d t h e p r o c e s s e s t h a t a f f e c t w a t e r q u a l i t y i n t h e v a l l e y w e n e e d t o c h a r a c t e r i z e t h e w a t e r q u a l i t y i n e a c h a q u i f e r b y d e t e r m i n i n g i f e a c h a q u i f e r h a s a d i s t i n c t c h e m i c a l s i g n a t u r e . T o e x a m i n e t h e d i f f e r e n c e s b e t w e e n t h e a q u i f e r s , t h e w e l l s s a m p l e d w e r e g r o u p e d a c c o r d i n g t o l o c a t i o n . B a s e d o n t h e f i n d i n g s i n s u b s e c t i o n s 4 . 2 . 1 - 4 . 2 . 3 , t h e f o l l o w i n g p a r a m e t e r s w e r e d e t e r m i n e d t o b e i n f l u e n c e d l a r g e l y b y g e o l o g y : c a l c i u m , s i l i c o n , o r t h o p h o s p h a t e , c o n d u c t i v i t y , m a g n e s i u m , s o d i u m a n d s t r o n t i u m . T h e s e p a r a m e t e r s w e r e c h o s e n b e c a u s e t h e y a r e h i g h l y c o r r e l a t e d w i t h e a c h o t h e r b u t n o t w i t h n i t r a t e a n d b e c a u s e n o n e o f t h e s e p a r a m e t e r s s h o w s a r e l a t i o n s h i p w i t h d e p t h . 56 300 200 100 E o 3 . o UJ ° 1 1 o19 ° 1 5 o38 ° 7 5 X 7f a W i n t e r n S u m m e r AQ1 AQ2 AQ3 Figure 21. Conductivity Boxplot 30 20 10 E 0 CO 11 °i2~r •Winter n S u m m e r 26 26 75 p75 =45 ° 4 5 X AQ1 A Q 2 A Q 3 Figure 23. Silicon Boxplot 40 30 15 1 = 1 Winter • Summer 75 ° 7 5 AQ1 AQ2 AQ3 Figure 22. Calcium Boxplot 0.5-0.4-0.3-i "5)0.2T E o ' 0 . 1 -Q. 1 75 55 * 53 AQ1 AQ2 AQ3 Figure 24. Orthophosphate Boxplot F o r t h i s a q u i f e r s p e c i f i c a n a l y s i s , w e l l s 3 6 - 3 9 w e r e r e m o v e d f r o m t h e d a t a b a s e , as t h e y a r e l o c a t e d w e s t o f A Q 2 o n t h e u p l a n d s j u s t e a s t o f M i s s i o n . A d d i t i o n a l l y t h e f o u r w e l l s w i t h t h e h i g h e s t c o n d u c t i v i t y w e r e r e m o v e d b e c a u s e , as p r e v i o u s l y d i s c u s s e d ( s e c t i o n 4 . 1 . 2 ) t h e y h a v e u n i q u e c h e m i s t r y a n d l i k e l y d r a w f r o m a d i f f e r e n t , d e e p e r , a q u i f e r t h a n t h e s h a l l o w e r w e l l s o n A Q 2 . F i g u r e s 2 1 - 2 4 s h o w b o x p l o t s f o r s o m e o f t h e g e o l o g i c a l l y i n f l u e n c e d p a r a m e t e r s g r o u p e d b y a q u i f e r . T h e s e p l o t s s h o w t h a t A Q l h a s h i g h e r v a l u e s f o r t h e s e p a r a m e t e r s t h a n t h e o t h e r t w o a q u i f e r s . K r u s k a l - W a l l i s t es t s f o l l o w e d b y M a n n -W h i t n e y t es t s w e r e r u n t o d e t e r m i n e w h i c h p a r a m e t e r w e r e s i g n i f i c a n t l y d i f f e r e n t f r o m e a c h o t h e r w h e n g r o u p e d a c c o r d i n g t o a q u i f e r . T h e K - W tes t s h o w e d t ha t t h e r e w e r e s i g n i f i c a n t d i f f e r e n c e s b e t w e e n at l e a s t 2 o f t h e t h r e e a q u i f e r s f o r a l l p a r a m e t e r s t e s t e d . T h e r e s u l t s o f t h e M a n n - W h i t n e y t es t s s h o w e d t ha t A Q 1 a n d A Q 3 h a v e v e r y d i s t i n c t c h e m i c a l s i g n a t u r e s , t h e m e d i a n w a s s i g n i f i c a n t l y d i f f e r e n t f o r e a c h p a r a m e t e r . A s u r p r i s i n g r e s u l t w a s t ha t d e s p i t e t h e p h y s i c a l s i m i l a r i t i e s b e t w e e n A Q l a n d A Q 2 ( b o t h a r e s h a l l o w a n d u n c o n f i n e d ) t h e w a t e r i n A Q 2 i s m u c h m o r e c h e m i c a l l y s i m i l a r t o t ha t o f A Q 3 ( the d e e p e r c o n f i n e d a q u i f e r ) t ha t t o t ha t o f A Q l . T h e r e w e r e s i g n i f i c a n t d i f f e r e n c e s b e t w e e n t h e w a t e r q u a l i t y o f A Q 1 a n d A Q 2 f o r a l l p a r a m e t e r s e x c e p t s o d i u m b u t b e t w e e n A Q 2 a n d A Q 3 o n l y s o d i u m a n d m a g n e s i u m ( i n s u m m e r ) h a d s i g n i f i c a n t l y d i f f e r e n t l e v e l s . S e v e r a l e x p l a n a t i o n s c a n b e g i v e n f o r t h e s e r e s u l t s . T h e s u b s t r a t e o f A Q 2 m a y b e g e o l o g i c a l l y s i m i l a r t o t ha t o f A Q 3 r e s u l t i n g i n w a t e r w h a t i s c h e m i c a l l y s i m i l a r . It i s a l s o p o s s i b l e t ha t t h e r e i s c o n t i n u o u s f l o w b e t w e e n A Q 2 a n d A Q 3 a n d t h a t t h e w a t e r i n A Q 2 57 o r i g i n a t e d i n A Q 3 a n d h a s s i m p l e f l o w e d s o u t h . M o r e d e t a i l e d t e c h n i c a l a n a l y s i s w o u l d n e e d to b e c o n d u c t e d t o c o n f i r m e i t h e r o f t h e s e t h e o r i e s . Table 16. Significance testing by aquifer, Kruskal-Wallis and Mann-Whitney tests K r u s k a l -W a l l i s M a n n - W h i t n e y U A Q 1 - A Q 2 | A Q 1 - A Q 3 A Q 2 - A Q 3 W W w E C M g C a N a S i S r P04 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** N . A . ** ** ** ** ** ** ** ** ** ** ** ** ** N . A . N . A . ( * * ) = s i g n i f i c a n t d i f f e r e n c e 4.4.1 Cluster Analysis I n a d d i t i o n t o t e s t i n g f o r s i g n i f i c a n t d i f f e r e n c e s b e t w e e n a q u i f e r s , c l u s t e r a n a l y s i s w a s u s e d t o d e t e r m i n e i f t h e c h e m i c a l p r o p e r t i e s o f t h e w a t e r l e d t o n a t u r a l g r o u p i n g s . A s f o r t h e p r e v i o u s s i g n i f i c a n c e t e s t i n g , w e l l s 3 6 - 3 9 a n d t h e h i g h c o n d u c t i v i t y w e l l s w e r e r e m o v e d b e f o r e s t a r t i n g t h i s a n a l y s i s s o t ha t o n l y w e l l s f r o m t h e 3 a q u i f e r s w e r e b e i n g c o m p a r e d . U s u a l l y t h i s p r o c e d u r e i s u s e d i n o r d e r t o f i n d u n k n o w n p a t t e r n s i n d a t a . I n t h i s c a s e i t w a s u s e d t o s e e i f a p r e d e t e r m i n e d p a t t e r n c o u l d b e j u s t i f i e d . T h e p u r p o s e w a s t o d i s c o v e r h o w t h e w e l l s w o u l d c l u s t e r b a s e d o n c h e m i s t r y a l o n e a n d n o t o n o u r p r e d e t e r m i n e d a q u i f e r s e p a r a t i o n . B e c a u s e c l u s t e r a n a l y s i s i s a s u b j e c t i v e o p e r a t i o n m a n y d i f f e r e n t c o m b i n a t i o n s o f c a l c i u m , c o n d u c t i v i t y , o r t h o p h o s p h a t e a n d s i l i c o n w e r e r u n . N o m a t t e r w h i c h c o m b i n a t i o n s w e r e u s e d , a f a i r l y c o n s i s t e n t p a t t e r n e m e r g e d ( s e e f i g 2 5 a n d a p p e n d i x 10 f o r t h e d e n d o g r a m o n w h i c h t h e d i a g r a m w a s b a s e d f o r a t y p i c a l e x a m p l e ) . T h e c l u s t e r i n g s h o w n i n f i g u r e 2 5 i s b a s e d o n l y o n t h e w i n t e r r e s u l t s f o r C a l c i u m a n d S i l i c o n w h i c h w e r e c h o s e n b e c a u s e t h e y b o t h h a d 1 0 0 % o f s a m p l e s a b o v e t h e d e t e c t i o n l i m i t a n d b e c a u s e t h e s e p a r a m e t e r s a r e k n o w n to b e i n f l u e n c e d m o s t l y b y g e o l o g y . T h e r e s u l t s s h o w a p a t t e r n t ha t s e e m s t o c o n f i r m t ha t t h e r e a r e a t l e a s t t w o s e p a r a t e g r o u n d w a t e r r e g i m e s i n t h e v a l l e y . O n e c l u s t e r w a s f o u n d i n t h e n o r t h e a s t o f t h e v a l l e y a n d c o v e r s m u c h o f A Q 3 ( c l u s t e r 1,0). A n o t h e r c l u s t e r w a s f o u n d w h i c h c o v e r e d m a i n l y t h e s o u t h o f t h e v a l l e y i n c l u d i n g H a t z i c I s l a n d ( c l u s t e r 3 O ) . T h e r e w a s v e r y l i t t l e o v e r l a p b e t w e e n c l u s t e r s t w o a n d t h r e e . F i n a l l y , c l u s t e r 2 ( * ) e n c o m p a s s e d t h e w e s t s i d e o f A Q 3 a n d t h e n o r t h o f A Q 2 . T h i s c l u s t e r w a s l e s s c o n s i s t e n t t h a n t he o t h e r c l u s t e r s a s i t c o v e r e d p a r t s o f A Q 2 a n d A Q 3 . 58 W h e n a K r u s k a l - W a l l i s tes t w a s r u n u s i n g t h e c l u s t e r s a s g r o u p i n g f a c t o r s i t w a s f o u n d tha t t h e r e w a s a s i g n i f i c a n t d i f f e r e n c e b e t w e e n t h e g r o u p s f o r b o t h c a l c i u m a n d s i l i c o n s u g g e s t i n g tha t o n e p a r a m e t e r w a s n o t d o m i n a t i n g t h e o t h e r i n d e t e r m i n i n g t h e c l u s t e r s . F i g u r e 2 6 s h o w s C a v s . S i g r o u p e d b y a q u i f e r . T h i s g r a p h c l e a r l y s h o w s t h e d i s t i n c t c h e m i s t r y o f A Q 1 w h i l e at t h e s a m e t i m e h i g h l i g h t i n g t h e s i m i l a r i t i e s b e t w e e n A Q 2 a n d A Q 3 . T h i s f i g u r e s u p p o r t s t he a r g u m e n t t h a t t h e w a t e r i n A Q 1 i s c h e m i c a l l y d i s t i n c t a n d t ha t A Q 2 a n d A Q 3 a r e d i f f i c u l t t o s e p a r a t e i n t o 59 d i s t i n c t c h e m i c a l g r o u p s . F i g u r e 2 7 s h o w s t h e s a m e t h i n g u s i n g d i f f e r e n t p a r a m e t e r s ; a g a i n A Q l i s d i s t i n c t f r o m A Q 2 a n d A Q 3 . 60 50 40 E 30 TO O 20 10 o o 6 b -O-o, 'o OAQ1 • AQ2 A A Q 3 0.0 5.0 10.0 15.0 Si (mg/L) 20.0 25.0 Figure 26. Silicon vs. Calcium (by aquifer) 300 250 „ 200 ~ 150 •a c o ° 100 50 0 • o —o A* • • - A - l A /Si i - o & ° ° ° ° OO o o -oo-o-o OAQ1 • AQ2 A A Q 3 0.00 0.10 0.20 0.30 0.40 0.50 0.60 P O 4 (mg/L) Figure 27. EC vs. P 0 4 (by Aquifer) F i n a l l y , f i g u r e 2 8 a g a i n s h o w s A Q l as h a v i n g d i f f e r e n t w a t e r q u a l i t y t h a n A Q 2 a n d A Q 3 , i n t h i s c a s e t h e r e l a t i o n s h i p i s m o r e l i n e a r ; h o w e v e r , t h e g r a p h s h o w s t h e s a m e t r e n d , t h a t A Q l h a s w a t e r q u a l i t y t ha t i s q u i t e d i s t i n c t f r o m A Q 2 a n d A Q 3 . 6 0 14.1 1 2 J _ 1 0 J o) 8 J E 6.i 4 J 2.i OJ o o • <p O O A O Q o Q D O A Q 1 • A Q 2 A A Q 3 0 . 0 0 0 . 0 5 0 . 1 0 0 . 1 5 Sr (mg/L) 0 . 2 0 Figure 2 8 . Mg vs. Sr (by aquifer) 4.4 Groundwater and Land use Interactions I n o r d e r t o b e t t e r p r o t e c t t h e q u a l i t y o f d r i n k i n g w a t e r s o u r c e s w e n e e d t o u n d e r s t a n d h o w l a n d u s e i n f l u e n c e s w a t e r q u a l i t y . T h e p r e v i o u s s e c t i o n s h a v e s h o w n t ha t , b e c a u s e i t i s n o t c o r r e l a t e d w i t h a n y o t h e r p a r a m e t e r a n d b e c a u s e o f i t s r e l a t i o n s h i p w i t h d e p t h , n i t r a t e i s t h e p a r a m e t e r m o s t i n f l u e n c e d b y l a n d u s e i n t h e H a t z i c V a l l e y . T h i s s e c t i o n w i l l e x p l o r e h o w l a n d u s e i n f l u e n c e s n i t r a t e l e v e l s . A s m e n t i o n e d i n t h e m e t h o d o l o g y , G I S w a s u s e d t o c a l c u l a t e t h e p e r c e n t a g e o f v a r i o u s l a n d u s e t y p e s a r o u n d e a c h w e l l w i t h i n t h r e e f i x e d r a d i i . T h e p e r c e n t a g e o f f o r e s t e d l a n d , a g r i c u l t u r a l l a n d , i n t e n s i v e l y u r b a n i s e d l a n d as w e l l as r u r a l r e s i d e n t i a l l a n d ( n o n - f o r e s t e d l a n d a r o u n d h o u s e s n o t i n s u b d i v i s i o n s b u t n o t u s e d f o r a g r i c u l t u r e ) w a s c a l c u l a t e d f o r 5 0 , 1 0 0 a n d 2 0 0 m r a d i i a r o u n d e a c h w e l l . T h e f i r s t p a r t o f t h e a n a l y s i s i n v o l v e d l o o k i n g a t c o r r e l a t i o n s b e t w e e n n i t r a t e - N l e v e l s a n d t h e p e r c e n t a g e o f t h e f o u r m a j o r l a n d u s e c a t e g o r i e s m e n t i o n e d a b o v e . A l l t h e w e l l s s a m p l e d w e r e u s e d f o r t h e i n i t i a l a n a l y s i s r e g a r d l e s s o f d e p t h o r l o c a t i o n . T h e c o r r e l a t i o n c o e f f i c i e n t s a r e s h o w n i n t a b l e 1 7 . T h e r e w e r e n o s i g n i f i c a n t c o r r e l a t i o n s b e t w e e n n i t r a t e a n d t h e p e r c e n t a g e o f a g r i c u l t u r e o r t h e p e r c e n t a g e o f r u r a l r e s i d e n t i a l l a n d s u r r o u n d i n g t h e w e l l s . T h e r e w a s , h o w e v e r , a s i g n i f i c a n t n e g a t i v e c o r r e l a t i o n b e t w e e n t h e p e r c e n t a g e o f f o r e s t e d l a n d a n d n i t r a t e l e v e l s , m e a n i n g t ha t as n i t r a t e l e v e l s i n t h e w e l l s i n c r e a s e d , t h e p e r c e n t a g e o f l a n d s u r r o u n d i n g t h e w e l l s t ha t w a s f o r e s t e d t e n d e d t o d e c r e a s e . A p o s i t i v e c o r r e l a t i o n b e t w e e n t h e p e r c e n t a g e o f u r b a n l a n d s u r r o u n d i n g t h e w e l l s a n d n i t r a t e l e v e l s w a s a l s o s e e n , m e a n i n g t ha t n i t r a t e l e v e l s t e n d e d to b e h i g h e r i n w e l l s t ha t w e r e s u r r o u n d e d b y m o r e h e a v i l y u r b a n i s e d l a n d . 61 I n p r e v i o u s s e c t i o n s i t w a s s h o w n t ha t t h e r e a r e n o w e l l s w i t h n i t r a t e l e v e l s a b o v e 3 m g / L t ha t a r e d e e p e r t h a n 12 m . T h i s c o n f i r m s t h a t l a n d u s e i s l i k e l y t o i m p a c t w e l l s t ha t a r e s h a l l o w a n d d u g i n t o u n c o n f i n e d a q u i f e r s . B a s e d o n t h e d e p t h s as w e l l as t h e g e o l o g i c a l p r o f i l e s p r e s e n t e d i n s e c t i o n 2 . 4 . 3 i t i s e v i d e n t t ha t m a n y o f t h e w e l l s i n A Q 3 a r e p r o t e c t e d b y a n a q u i t a r d . A d d i t i o n a l l y , a s m e n t i o n e d i n s e c t i o n 2 . 4 t h e l a n d u s e m i r r o r s t h e a q u i f e r b o u n d a r i e s t o a l a r g e e x t e n t . T h i s m e a n s t ha t t h e d e e p e r w e l l s i n A Q 3 a r e a l s o m o r e l i k e l y t o b e s u r r o u n d e d b y f o r e s t t h a n m a n y o f t he s h a l l o w e r w e l l s i n A Q 1 a n d A Q 2 . T h i s m a k e i t d i f f i c u l t t o k n o w i f t h e r e a s o n t ha t w e l l s w i t h a g r e a t e r p e r c e n t a g e o f f o r e s t s u r r o u n d i n g t h e m h a v e l o w e r n i t r a t e i s d u e to t h e f o r e s t o r t h e d e p t h a n d p r o t e c t e d n a t u r e o f t h e w e l l s . Table 17. Spearman's Rank Correlation Coefficients (r): Land Use vs. Nitrate W e l l s C o r r e l a t e d Ag 50 Ag 100 Ag 200 For 50 For 100 For 200 Al l W i n t e r 0.192 0.201 0.207 -0.349** -0.344** -0.346** Wells S u m m e r 0.153 0.154 0.153 -0.318** -0.282* -0.277** <15 m W i n t e r 0.064 0.072 0.049 -0.425** -0.449** -0.440** Deep S u m m e r 0.05 0.063 0.042 -0.469** -0.448** -0.464** Urb 50 Urb 100 Urb 200 Rur 50 Rur100 Rur 200 All W i n t e r 0.220 0.204 0.327** 0.062 0.028 -0.125 Wells S u m m e r 0.255* 0.240* 0.298** 0.062 0.041 -0.047 <15 m W i n t e r 0.315* 0.364* 0.449** 0.185 0.356* 0.216 Deep S u m m e r 0.471* 0.514* 0.521** 0.120 0.255 0.207 * * C o r r e l a t i o n i s s i g n i f i c a n t a t t h e 0 .01 l e v e l ( 2 - t a i l e d ) * C o r r e l a t i o n i s s i g n i f i c a n t a t t h e 0 . 0 5 l e v e l ( 2 - t a i l e d ) I n o r d e r t o a t t e m p t t o r e m o v e t h e b i a s w h e r e d e e p e r w e l l s , w h i c h a r e l a r g e l y s u r r o u n d e d b y f o r e s t m a y a p p e a r t o h a v e l o w l e v e l s o f n i t r a t e s o l e l y b e c a u s e o f t he a m o u n t o f f o r e s t s u r r o u n d i n g t h e m t h e c o r r e l a t i o n s w e r e r e - c a l c u l a t e d u s i n g o n l y t h o s e w e l l s t ha t w e r e 15 m d e e p o r l e s s . T h i s l e f t 5 7 % o f t he w e l l s s a m p l e d o r a b o u t 4 4 w e l l s . T h e s a m e r e l a t i o n s h i p s w i t h f o r e s t a n d u r b a n l a n d w e r e f o u n d ( s e e t a b l e 1 7 ) . W h e n l o o k i n g o n l y a t t h e s h a l l o w w e l l s t h e c o r r e l a t i o n s b e t w e e n t h e p e r c e n t a g e o f u r b a n l a n d a n d n i t r a t e w e r e e v e n s t r o n g e r . T h e c o r r e l a t i o n c o e f f i c i e n t f o r t h e 2 0 0 m b u f f e r i n s u m m e r w a s 0 . 5 2 1 ( t he s t r o n g e s t c o r r e l a t i o n i n t a b l e 1 7 ) . I n o r d e r t o f u r t h e r u n d e r s t a n d t h e s e r e l a t i o n s h i p s t he w e l l s w e r e s e p a r a t e d i n t o t h r e e g r o u p s b a s e d o n t h e l a n d u s e p e r c e n t a g e s f o r e a c h w e l l . U s i n g a g r i c u l t u r e a s a n e x a m p l e , t h e g r o u p s w e r e c r e a t e d a s f o l l o w s . G r o u p o n e c o n t a i n e d t h o s e w e l l s w i t h b e t w e e n 0 a n d 5 % a g r i c u l t u r a l l a n d w i t h i n t h e b u f f e r ( t he 1 0 0 m b u f f e r s w e r e u s e d f o r t h i s a n a l y s i s ) . G r o u p t w o c o n t a i n e d t h o s e w e l l s w i t h 5 - 5 0 % a g r i c u l t u r e a n d f i n a l l y g r o u p t h r e e e n c o m p a s s e s t h e r e m a i n i n g w e l l s , t h o s e w i t h 5 0 - 1 0 0 % a g r i c u l t u r a l l a n d w i t h i n t h e 1 0 0 m b u f f e r . T h e w e l l s w e r e g r o u p e d i n t h i s m a n n e r f o r e a c h o f t h e f o u r m a j o r l a n d u s e s . T h e n i t r a t e l e v e l s w e r e t e s t e d b a s e d o n t h e s e t h r e e g r o u p s t o d e t e r m i n e i f t h e y w e r e s i g n i f i c a n t l y d i f f e r e n t . A s w i t h t h e c o r r e l a t i o n c o e f f i c i e n t s t h e r e s u l t s o f t h e K r u s k a l - W a l l i s tes t s h o w e d t ha t t h e o n l y s i g n i f i c a n t d i f f e r e n c e s i n n i t r a t e l e v e l s w h e n g r o u p e d b y l a n d u s e r a n k s w e r e s e e n w h e n c o m p a r i n g t h e f o r e s t e d r a n k s a n d t h e u r b a n r a n k s . T h e r e w e r e n o s i g n i f i c a n t d i f f e r e n c e s i n n i t r a t e l e v e l s i f t h e y w e r e b a s e d o n a g r i c u l t u r e o r 62 r u r a l r e s i d e n t i a l l a n d p e r c e n t a g e s . F i g u r e s 2 9 a n d 3 0 s h o w t h e b o x p l o t o f t h e d i f f e r e n c e s i n n i t r a t e w h e n d i v i d e d b y f o r e s t a n d u r b a n l a n d u s e r a n k s . F i g u r e 2 9 s h o w s t ha t t h e n i t r a t e l e v e l s a r e h i g h e r w h e r e t h e r e i s t h e l e a s t f o r e s t e d l a n d . T h e r e w e r e s i g n i f i c a n t d i f f e r e n c e s b e t w e e n g r o u p 1 & 2 a n d g r o u p s 1 & 3 b u t n o t b e t w e e n g r o u p s 2 & 3 . T h e s a m e r e s u l t s w e r e o b t a i n e d r e g a r d l e s s o f w h e t h e r o r n o t a l l t h e w e l l s o r o n l y t h e s h a l l o w e s t w e l l s w e r e t e s t e d . T h e s e r a n k s w e r e a p p l i e d t o a n d t e s t e d o n t he 1 0 0 m a n d 2 0 0 m b u f f e r s . F i g u r e s 2 9 a n d 3 0 a r e b o x p l o t s o f t h e 1 0 0 m b u f f e r . 14 12 10 81 6 I* E 2 2 CO k. z 0 on Q19 • Winter r~~J Summer *10 *58 *53 -x58 *53 N = 7 7 5-50% 13 13 50-100% 24 24 0-5% % Forest Ranks Figure 29. Boxplot - Nitrate vs. Forest Ranks (winter and summer) for a 100 m land use buffer 63 14 12 10 8 TO 6 g 0) 4 re 4-* z 2 0 *19 *79 0 1 6 C68 *19 -*1§ 36 36 0-5% *11 5 5 5-50% •Winter •Summer 3 3 50-100% % Urbanized Land - Ranked Figure 30. Boxplot - Nitrate vs. Urban Ranks (winter and summer) for a 100 m land use buffer F i g u r e 3 0 d i s p l a y s t h e r e l a t i o n s h i p b e t w e e n n i t r a t e l e v e l a n d t h e p e r c e n t a g e o f u r b a n l a n d s u r r o u n d i n g t h e w e l l s . T h e l e v e l o f n i t r a t e i n c r e a s e s a s t h e a m o u n t o f u r b a n l a n d i n c r e a s e s . I n t h i s c a s e t h e r e a r e s l i g h t s e a s o n a l d i f f e r e n c e s e v i d e n t w i t h t h e m o s t u r b a n i s e d w e l l s b e i n g m o s t h i g h l y i m p a c t e d i n t h e s u m m e r . T h i s t r e n d i s a l s o e v i d e n t i n t h e c o r r e l a t i o n c o e f f i c i e n t w h e r e t h e c o e f f i c i e n t i s h i g h e r f o r t h e s u m m e r f o r t h e u r b a n i s e d l a n d . T h e r e s u l t s c a n b e e x p l a i n e d as f o l l o w s . L a n d tha t i s f o r e s t e d p r o t e c t s g r o u n d w a t e r b e c a u s e t h e s e a r e a s d o n o t h a v e a s m a n y i n p u t s a s t he l a n d tha t i s n o t f o r e s t e d . A s d i s c u s s e d i n s e c t i o n 4 . 1 . 5 , i n o n e c a s e ( w e l l 5 8 ) h i g h l e v e l s o f n i t r a t e w e r e e v i d e n t i n a w e l l , w h i c h , b a s e d o n a i r p h o t o s a p p e a r s t o b e c o m p l e t e l y s u r r o u n d e d b y f o r e s t . A v i s i t t o t h i s p r o p e r t y r e v e a l e d n u m e r o u s l i v e s t o c k r o a m i n g f r e e l y t h r o u g h o u t t h e y a r d , w h i c h i s a v e r y p r o b a b l e s o u r c e f o r n i t r a t e . T h i s w e l l w a s a l s o q u i t e s h a l l o w ( 7 . 6 2 m ) i n c r e a s i n g i t s v u l n e r a b i l i t y . F o r e s t e d l a n d d o e s n o t c a u s e l o w n i t r a t e b u t g e n e r a l l y a c t i v i t i e s t ha t a r e l i k e l y t o c o n t r i b u t e n i t r o g e n t o g r o u n d w a t e r a r e n o t f o u n d i n f o r e s t s ( t h e a b o v e e x a m p l e i s o n e o f m a n y p o s s i b l e e x c e p t i o n s ) . It w a s s u r p r i s i n g t o f i n d n o c o r r e l a t i o n s b e t w e e n n i t r a t e l e v e l s a n d a g r i c u l t u r e . O t h e r s t u d i e s i n t h e L o w e r F r a s e r V a l l e y ( S c h r e i e r et al, 2 0 0 3 ; S c h r e i e r et al, 1 9 9 6 ; L e i b s h e r et al, 1 9 9 2 ; Z e b a r t h et al, 1 9 9 8 ) a n d e l s e w h e r e ( N o l a n a n d S t o n e r , 2 0 0 0 ; B u r k a r t a n d S t o n e r , 2 0 0 2 ) h a v e i m p l i c a t e d a g r i c u l t u r a l a c t i v i t y a s t h e m a j o r c a u s e o f n i t r a t e p o l l u t i o n i n v a r i o u s a q u i f e r s t h r o u g h o u t N o r t h A m e r i c a a n d t h e w o r l d . M a n y a g r i c u l t u r a l a c t i v i t i e s , e s p e c i a l l y u s e o f c o m m e r c i a l f e r t i l i z e r a n d s p r e a d i n g o f m a n u r e o f t e n l e a d t o 64 s i t u a t i o n s w h e r e t h e a m o u n t o f n i t r o g e n a p p l i e d t o t h e l a n d i s i n e x c e s s o f t h e r e q u i r e m e n t s o f c r o p s o r l a n d c o v e r . S i n c e n i t r a t e i s s o l u b l e , t h e s u r p l u s e n d s u p i n g r o u n d w a t e r . T h e l a c k o f s t a t i s t i c a l c o r r e l a t i o n b e t w e e n g r o u n d w a t e r n i t r a t e a n d t h e p e r c e n t a g e o f a g r i c u l t u r e s u r r o u n d i n g w e l l s i n t h e H a t z i c V a l l e y i s l i k e l y d u e t o o n e o r m o r e o f t h e f o l l o w i n g f a c t o r s . T h e t y p e o f a g r i c u l t u r e p r a c t i c e d i n t h e H a t z i c V a l l e y i s n o t as i n t e n s i v e a s t ha t p r a c t i c e d e l s e w h e r e i n t h e L o w e r F r a s e r V a l l e y . T h e r e a r e n o l a r g e c h i c k e n o r p i g f a r m s n o r a r e t h e r e l a r g e a r e a s o f i n t e n s i v e h o r t i c u l t u r e w i t h i n 2 0 0 m o f a n y o f t h e w e l l s s a m p l e d . A d d i t i o n a l l y , H a t z i c P r a i r i e i s t h e a r e a o f t h e v a l l e y w i t h t h e m o s t a g r i c u l t u r e b u t i t a l s o t h e a r e a w h e r e t h e l e a s t g r o u n d w a t e r s a m p l e s w e r e t a k e n . T h e s a m p l e s t ha t w e r e t a k e n w e r e l a r g e l y c l u s t e r e d t o w a r d s t h e n o r t h o f t h e a r e a w h e r e t h e l a n d u s e i s m o r e m i x e d . T h i s u n - e v e n s a m p l i n g c a n l a r g e l y b e a t t r i b u t e d to c h a n c e , i n v i t a t i o n s t o p a r t i c i p a t e w e r e s e n t t o h o u s e h o l d t h r o u g h o u t t h e w a t e r s h e d b u t t h e r e w a s l i m i t e d c o n t r o l o v e r t h e s p a t i a l d i s t r i b u t i o n o f t h o s e w h o a g r e e d t o p a r t i c i p a t e . A d d i t i o n a l l y , r e s i d e n t s r e p o r t e d t ha t s u r f a c e w a t e r w a s a p o p u l a r a l t e r n a t i v e to g r o u n d w a t e r f o r d o m e s t i c u s e i n t h e A Q 2 a r e a d u e t o h i g h i r o n l e v e l s f o u n d i n t h e g r o u n d w a t e r . T h e r e w e r e s e v e r a l w e l l s w i t h h i g h n i t r a t e l e v e l s t ha t w e r e l o c a t e d i n p r i m a r i l y a g r i c u l t u r a l a r e a s . T h e s e w e l l s , w e r e , h o w e v e r t h e e x c e p t i o n r a t h e r t h a n t h e r u l e . A l l w e l l s i n p r i m a r i l y a g r i c u l t u r a l a r e a s w i t h h i g h n i t r a t e l e v e l s w e r e l e s s t h a n 1 2 m d e e p . T h e m a j o r i t y o f w e l l s w i t h h i g h n i t r a t e w e r e f o u n d i n t h e s m a l l s u b d i v i s i o n s o n H a t z i c I s l a n d . S i g n i f i c a n t c o r r e l a t i o n s w e r e f o u n d b e t w e e n t h e p e r c e n t a g e o f u r b a n i s e d l a n d a n d t h e l e v e l o f n i t r a t e . T h e s e a r e a s a r e q u i t e d e n s e l y p o p u l a t e d b u t l a c k t h e s e r v i c e s f o u n d i n m o s t u r b a n a r e a s , t ha t i s , e a c h h o u s e h o l d h a s a n i n d i v i d u a l w e l l a n d i n d i v i d u a l s e p t i c s y s t e m . T h e s o u r c e o f n i t r a t e i n t h e s e a r e a s i s l i k e l y f r o m t h e s e p t i c s y s t e m s , w h i c h a r e t o o d e n s e to f u n c t i o n p r o p e r l y . T h e s e p t i c d e n s i t y i s v e r y h i g h a n d t h e w a t e r t a b l e i s n e a r t h e s u r f a c e at d i f f e r e n t t i m e s o f t h e y e a r . T h i s c r e a t e s c h a l l e n g i n g c o n d i t i o n s f o r s e p t i c s y s t e m s to f u n c t i o n p r o p e r l y a l l y e a r r o u n d . 65 4.6 Surface Water Quality S u r f a c e w a t e r s a m p l e s f r o m 1 9 s t a t i o n s t h r o u g h o u t t he v a l l e y w e r e t a k e n b e t w e e n M a y 2 0 0 2 a n d M a r c h 2 0 0 3 ( s e e f i g u r e 12 f o r l o c a t i o n o f s t a t i o n s ) . S e v e n t e e n o f t h e s e s t a t i o n s w i l l b e a n a l y z e d h e r e . S t a t i o n 7 i s o m i t t e d b e c a u s e i t w a s d r y f o r m o s t o f t h e s u m m e r a n d t h e r e f o r e c a n n o t b e i n c l u d e d i n s e a s o n a l c o m p a r i s o n s a n d s t a t i o n 2 0 i s o m i t t e d b e c a u s e i t w a s n o t l o c a t e d i n t h e s t u d y a r e a . T h e f o l l o w i n g p a r a m e t e r s w e r e i n v e s t i g a t e d : n i t r a t e , t e m p e r a t u r e a n d c o n d u c t i v i t y . T h e r e s u l t s w e r e d i v i d e d i n t o t w o g r o u p s r e p r e s e n t i n g t h e " d r y s e a s o n " ( M a y t o O c t . ) a n d t h e " w e t s e a s o n " ( N o v . t o M a r c h ) . T h e a v e r a g e o f e a c h p a r a m e t e r w a s c a l c u l a t e d f o r t h e s e s e a s o n s s o t h a t e a c h s t a t i o n h a s a d r y ( s u m m e r ) a n d a w e t ( w i n t e r ) v a l u e . I n c o n t r a s t w i t h t he g r o u n d w a t e r s a m p l e s t h e r e w e r e s i g n i f i c a n t d i f f e r e n c e s b e t w e e n s e a s o n s f o r a l l p a r a m e t e r s m e a s u r e d w h e n t h e M a n n - W h i t n e y U tes t s w e r e r u n o n t h e s t r e a m d a t a . I n o r d e r t o u n d e r s t a n d h o w the w a t e r q u a l i t y c h a n g e s a s t h e s t r e a m s r u n t h e i r c o u r s e , e a c h s t r e a m h a s b e e n d i v i d e d u p i n t o a m a i n s t e m a n d t r i b u t a r i e s a n d c h a n g e s i n p a r a m e t e r l e v e l s e x a m i n e d f r o m u p s t r e a m t o d o w n s t r e a m . F i g u r e 31 s h o w s t h e s t a t i o n s o n t h e m a i n s t e m a n d t h e l o c a t i o n o f s t a t i o n s o n t h r e e o f t h e t r i b u t a r i e s . E a c h s t r e a m w a s b u f f e r e d b y 1 0 0 m u s i n g t h e G I S s o f t w a r e . T h e a r e a a n d p e r c e n t a g e o f e a c h l a n d u s e t y p e u p s t r e a m o f t h e s t a t i o n s w a s c a l c u l a t e d . T h e l a n d u s e w a s c a l c u l a t e d c u m u l a t i v e l y a n d t h e r e f o r e d o w n s t r e a m s t a t i o n s i n c l u d e a l l t h e l a n d a r e a u p s t r e a m o f t ha t s t a t i o n . 66 Figure 31. Hatzic Val ley Mainstem and Selected Tributaries 67 4.6.1 Temperature F i g u r e s 3 2 - 3 5 s h o w t h e a v e r a g e w e t a n d d r y s e a s o n t e m p e r a t u r e a t e a c h s t a t i o n o n t h e m a i n s t e m a n d f o r t h r e e t r i b u t a r i e s ( N o t e tha t s t a t i o n 14 r e p r e s e n t s t he c o n f l u e n c e o f t h e m a i n s t e m a n d 3 t r i b u t a r i e s ; t h e r e f o r e , e a c h g r a p h i s t h e s a m e b e y o n d s t a t i o n 14 . T h i s i s d e n o t e d b y a d a s h e d l i n e r u n n i n g t h r o u g h s t a t i o n 14 o n f i g u r e s 3 2 - 4 3 ) . A s o n e w o u l d e x p e c t t h e t e m p e r a t u r e i s h i g h e r i n t h e d r y s e a s o n ( s u m m e r ) t h a n i n t h e w e t s e a s o n ( w i n t e r ) . T h e s t r e a m s i n t h e H a t z i c W a t e r s h e d f l o w t h r o u g h t w o m a i n l a n d u s e s , f o r e s t e d a n d a g r i c u l t u r a l . I n g e n e r a l t h e a m o u n t o f a g r i c u l t u r a l l a n d u p s t r e a m f r o m a n y s t a t i o n i n c r e a s e s a s o n e m o v e d d o w n s t r e a m . S i g n i f i c a n t c o r r e l a t i o n s w e r e f o u n d b e t w e e n t h e t e m p e r a t u r e a n d t h e p e r c e n t a g e o f f o r e s t e d l a n d a n d t h e p e r c e n t a g e o f a g r i c u l t u r e . T e m p e r a t u r e t e n d e d t o i n c r e a s e a s t h e p e r c e n t a g e o f a g r i c u l t u r e u p s t r e a m i n c r e a s e d a n d d e c r e a s e a t t h o s e s t a t i o n s w h e r e t h e p e r c e n t a g e o f f o r e s t e d l a n d u p s t r e a m w a s g r e a t e r ( S e e t a b l e 18 f o r t h e c o r r e l a t i o n c o e f f i c i e n t s ) . I n w i n t e r t h e t e m p e r a t u r e i s q u i t e c o n s t a n t f o r a l l t h e t r i b u t a r i e s . I n t h e s u m m e r t h e t e m p e r a t u r e i n c r e a s e s f r o m u p s t r e a m t o d o w n s t r e a m . T h i s f i t s w i t h t h e c o r r e l a t i o n s m e n t i o n e d e a r l i e r . S t a t i o n s 8 a n d 10 h a v e l o w e r t e m p e r a t u r e s i n t h e s u m m e r t h a n m o s t o f t h e o t h e r s t a t i o n s . T h i s i s l i k e l y d u e t o t h e i n f l u e n c e o f g r o u n d w a t e r o n t h e f l o w o f t h e s t r e a m s i n t h e s e l o c a t i o n s . G r o u n d w a t e r a n d s t r e a m w a t e r i n t e r a c t i o n s w i l l b e d i s c u s s e d i n m o r e d e t a i l i n a s u b s e q u e n t s e c t i o n . Table 18. Spearman's Rank Correlation Coefficients (r) Surface Water vs. Land Use %Forested % Agriculture Temperature (Dry) Temperature (Wet) Conductivity (Dry) Conductivity (Wet) -0.696 (**) -0.662 (**) -0.581 (*) -0.569 (*) 0.732 (**) 0.656 (**) 0.631 (") 0.592 (*) (**) significant at 0.01 (*) significant at 0.05 4.6.2 Nitrate F i g u r e s 3 6 - 3 9 s h o w t h e d r y a n d w e t s e a s o n v a l u e s f o r n i t r a t e f r o m u p s t r e a m t o d o w n s t r e a m . T h e g r a p h o f t h e m a i n s t e m s h o w s a s p i k e a t s t a t i o n 14 . B y e x a m i n i n g t h e t r i b u t a r i e s i t i s e v i d e n t t ha t t h e e l e v a t e d n i t r a t e i s c o m i n g f r o m t r i b u t a r y 2 i n t he v i c i n i t y o f s t a t i o n 1 3 . T h e s o u r c e o f t h i s n i t r a t e i s l i k e l y a g r i c u l t u r a l a s t h e r e a r e f a r m s n e a r b y . It s h o u l d b e n o t e d t ha t t h e s e n i t r a t e v a l u e s a r e a l l q u i t e l o w , b e l o w t h e 3 m g / L t h a t w e c o n s i d e r e d i n d i c a t i v e o f p o l l u t e d w a t e r w h e n l o o k i n g a t t h e g r o u n d w a t e r s a m p l e s . H o w e v e r , t h e m a x i m u m v a l u e m e a s u r e a t s t a t i o n 13 ( 2 . 5 1 m g / L ) i s h i g h e r t h a n t h e b a c k g r o u n d a n d t h e r e f o r e , i n d i c a t e s a n t h r o p o g e n i c i n f l u e n c e . T h e n i t r a t e l e v e l s i n t h e s t r e a m s t h r o u g h o u t t h e v a l l e y a r e h i g h e r i n w i n t e r t h a n i n s u m m e r f o r s e v e r a l r e a s o n s . T h e m a i n s o u r c e o f n i t r a t e i n s t r e a m s i s f r o m r u n - o f f f r o m a g r i c u l t u r a l f i e l d s . I n t h e s u m m e r t h e r e i s l e s s r u n - o f f b e c a u s e i t r a i n s l e s s ; t h e r e f o r e , a n y n i t r a t e t ha t i s o n t h e f i e l d s o r r u n s o f f i s b e i n g t a k e n u p b y t h e p l a n t s a n d a q u a t i c b i o t a t h a t a r e g r o w i n g d u r i n g t h i s t i m e . I n w i n t e r , t he o p p o s i t e o c c u r s , r u n - o f f i n c r e a s e s as t h e w e a t h e r g e t s w e t t e r a n d u p t a k e 68 d e c r e a s e s b e c a u s e t h e p l a n t s a r e n o t g r o w i n g . I f t h e s u m m e r n i t r a t e l e v e l s w e r e h i g h i t w o u l d l i k e l y b e d u e to g r o u n d w a t e r c o n t a m i n a t i o n . T h e l o w s u m m e r n i t r a t e v a l u e s i n d i c a t e t ha t t h i s i s n o t t h e c a s e . 4.6.3 Conductivity T h e f i n a l p a r a m e t e r m e a s u r e d i s c o n d u c t i v i t y ( f i g u r e s 4 0 - 4 3 ) . T h e c o n d u c t i v i t y v a l u e s a r e h i g h e r i n t h e s u m m e r t h a n i n t h e w i n t e r d u e t o t h e f a c t t ha t t h e r e i s l e s s w a t e r i n t h e s t r e a m s i n s u m m e r t h a n i n w i n t e r w h i c h t h e r e f o r e l e a d s t o a c o n c e n t r a t i n g e f f e c t . T h e r e i s a b i g j u m p i n c o n d u c t i v i t y b e t w e e n s t a t i o n 6 a n d 11 o n t h e m a i n s t e m . T h i s i s n o t d u e t o a g r i c u l t u r a l a c t i v i t y b u t l i k e l y d u e t o s o m e i n s t r e a m w o r k a n d o t h e r u r b a n a c t i v i t y t ha t o c c u r s n e a r t h i s s t a t i o n . A h i g h c o n d u c t i v i t y ( o v e r 2 0 0 0 u S / c m ) r i v u l e t w a s f o u n d d r a i n i n g i n t o t h e m a i n s t e m at s t a t i o n 1 1 . It w a s n o t p o s s i b l e t o f o l l o w t h i s t o t h e s o u r c e as i t c a m e f r o m u n d e r a f e n c e o n p r i v a t e p r o p e r t y . T h e c o n d u c t i v i t y a t s t a t i o n 8 i s a l s o q u i t e h i g h , l i k e l y f r o m t h e i n f l u e n c e o f g r o u n d w a t e r r e c h a r g e at t h i s s t a t i o n . I n t h e w i n t e r w h e n t h e r e i s m o r e w a t e r i n t h e s t r e a m s t h e c o n d u c t i v i t y i s l o w e r d u e t o d i l u t i o n . S t a t i o n s 3 a n d 4 s a m p l e s t r e a m s t h a t c o m e o f f t h e m o u n t a i n s a f t e r f l o w i n g o v e r a f a i r l y i n e r t s u b s t r a t e . S i n c e t h e s e s t r e a m s a r e n o t i n f l u e n c e d b y l a n d u s e , t h e y h a v e s i m i l a r c o n d u c t i v i t y t h r o u g h o u t t h e y e a r . T h e r e w e r e s i g n i f i c a n t c o r r e l a t i o n s b e t w e e n t h e l a n d u s e a n d t h e c o n d u c t i v i t y s e e n i n t he s t r e a m s . S t r e a m s t e n d t o h a v e l o w e r c o n d u c t i v i t y at s t a t i o n s t ha t r u n t h r o u g h f o r e s t s t h a n t h o s e t ha t r u n t h r o u g h a g r i c u l t u r a l l a n d ( s e e t a b l e 1 8 ) . N o n e o f t h e s t r e a m s r u n p a s t t h e u r b a n a r e a s o n H a t z i c I s l a n d ( t h e r e i s n o s u r f a c e w a t e r o n t h e i s l a n d ) s o n o c o m p a r i s o n s c a n b e m a d e . T h e s e r e s u l t s s h o w tha t l a n d u s e i n t h e H a t z i c V a l l e y i n f l u e n c e s t h e w a t e r q u a l i t y i n t h e s t r e a m s t h a t r u n t h r o u g h t h e v a l l e y . L o c a l l y , a g r i c u l t u r a l a c t i v i t y c a n r a i s e n i t r a t e l e v e l s a l t h o u g h t h i s t r e n d i s n o t s e e n c o n s i s t e n t l y t h r o u g h o u t t h e v a l l e y . T h e r e i s a c o n s i s t e n t s i g n i f i c a n t ( a = 0 . 0 5 ) c o r r e l a t i o n b e t w e e n t e m p e r a t u r e a n d c o n d u c t i v i t y a n d a m o u n t o f a g r i c u l t u r a l o r f o r e s t e d l a n d t h r o u g h o u t t h e w a t e r s h e d . T h e n e x t s e c t i o n w i l l d i s c u s s h o w s u r f a c e w a t e r a n d g r o u n d w a t e r i n t e r a c t i n t h e v a l l e y . 6 9 20 5 -| 1 , 1 , 1 , 1 , h --e-Dry 6 11 14 17 19 —•—Wet Stations - Upstream to Downstream—^-Figure 32. Average Dry and Wet Season Temperatures - Mainstem O o 20 15 | 10 — o 9 8 10 14 17 19 -O- Dry Stations - Upstream to -s—W e t Downstream — • Figure 33. Average Dry and Wet Season Temperatures - Tributary 1 13 15 14 17 19 Stations - Upstream to -m— Wet Downstream ^ - G - D r y Figure 34. Average Dry and Wet Season Temperatures - Tributary 2 4 5 16 14 17 19 -©— Dry Stations - Upstream to -o—Wet Downstream • Figure 35. Average Dry and Wet Season Temperatures - Tributary 3 70 -e-Dry -a-Wet 0.0 -©—Dry -•—Wet 11 14 17 Stations - Upstream to Downstream 19 Figure 36. Average Wet and Dry Season Nitrate Levels - Mainstem 2.0 8 10 14 17 Stations - Upstream to Downstream 19 -e-Dry - • - W e t 13 15 14 17 19 Stations - Upstream to Downstream Figure 37. Average Wet and Dry Season Nitrate Figure 38. Average Wet and Dry Season Nitrate Levels - Tributary 1. Levels - Tributary 2. -e-Dry -a-Wet 5 16 14 17 Stations - Upstream to Downstream Figure 39. Average Wet and Dry Season Nitrate Levels - Tributary 3. 71 160 -j 140 'cm) 120 CO 100 ivity 80 ucti 60 "D C o 40 o 20 0 -©--Dry • Wet 11 14 17 Stations - Upstream to Downstream-19 Figure 40. Average Dry and Wet Season Conductivity - Mainstem ~ 160 E o CO •a c o CJ 120 80 40 0 -©—Dry -m—- Wet 9 8 10 14 17 19 Stations - Upstream to Downstream—fc--Dry Wet ^ ~ - ~ e 0 0 i I g 1 13 15 14 17 19 Stations - Upstream to Downstream Figure 41. Average Dry and Wet Season Conductivity - Tributary 1. Figure 42. Average Dry and Wet Season Conductivity - Tributary 2. 4 5 16 14 17 19 Dry Stations - Upstream to -Wet Downstream—p-Figure 43. Average Dry and Wet Season Conductivity - Tributary 3. 72 4.7 Groundwater and Surface Water Interactions I n t e r a c t i o n s b e t w e e n g r o u n d w a t e r a n d s u r f a c e w a t e r c a n h a v e a c o n t r o l l i n g i n f l u e n c e o n s t r e a m c h e m i s t r y as w e l l as i n f l u e n c e t h e b i o l o g i c a l c o n d i t i o n s i n a n d n e a r s t r e a m s ( O x t o b e e a n d N o v a k o w s k i , 2 0 0 2 ) . P r e v i o u s r e s e a r c h h a s s h o w n t ha t d e t e r i o r a t i o n o f s u r f a c e w a t e r q u a l i t y i n a r e a s o f i n t e n s i v e a g r i c u l t u r e c a n r e s u l t f r o m c o n t a m i n a t e d s h a l l o w g r o u n d w a t e r d i s c h a r g i n g i n t o s t r e a m s ( C e y et al., 1998; B e r k a et ai, 2 0 0 1 ) . It i s , t h e r e f o r e , i m p o r t a n t t o u n d e r s t a n d t h e i n t e r a c t i o n b e t w e e n g r o u n d w a t e r a n d s u r f a c e w a t e r i n o r d e r t o d e t e r m i n e t h e m i g r a t i o n p a t h w a y s f o r c o n t a m i n a n t s . T h e s e i n t e r a c t i o n s b e c o m e e v e n m o r e i m p o r t a n t i n w a t e r s h e d s w h e r e g r o u n d w a t e r m a k e s u p m o s t o r a l l o f t h e f l o w d u r i n g d r y p e r i o d s . T h i s s e c t i o n w i l l l o o k a t t h e r e s u l t s o f t he g r o u n d w a t e r a n d s t r e a m w a t e r s a m p l i n g i n t h e H a t z i c V a l l e y a n d a t t e m p t t o d e t e r m i n e i f t h e r e a r e s e c t i o n s o f t h e s t r e a m s a m p l i n g n e t w o r k w h e r e g r o u n d w a t e r i n f l u e n c e c a n b e s e e n o r a r e a s w h e r e s u r f a c e w a t e r i n f l u e n c e o n t h e g r o u n d w a t e r q u a l i t y c a n b e e n s e e n . A s t h e m a j o r i t y o f t h e s t r e a m s a m p l i n g s t a t i o n s a r e l o c a t e d o n H a t z i c P r a i r i e ( A Q 2 ) , w h i c h c o r r e s p o n d s to t h e a r e a w h e r e t h e l e a s t g r o u n d w a t e r s a m p l e s w e r e t a k e n , t h e r e i s o n l y a s m a l l p a r t o f t h e s a m p l i n g n e t w o r k w h e r e t h e r e i s s u f f i c i e n t o v e r l a p b e t w e e n t h e s t r e a m s a m p l i n g n e t w o r k a n d g r o u n d w a t e r s a m p l i n g n e t w o r k t o a t t e m p t t o o b s e r v e g r o u n d w a t e r a n d s t r e a m w a t e r i n t e r a c t i o n s b a s e d o n d i r e c t c o m p a r i s o n s . T h i s a r e a i s i l l u s t r a t e d i n f i g u r e 4 4 a n d i s l o c a t e d i n t h e m i d d l e o f t he v a l l e y w h e r e A Q 3 a n d A Q 2 m e e t . T h e a r e a i n c l u d e s t h e s a m p l i n g s t a t i o n s o n O r u , D u r i e u a n d B e l c h a r t o n c r e e k ( s t a t i o n s 8-10 ) a l o n g D u r i e u R o a d a n d t h e n e a r b y g r o u n d w a t e r s a m p l i n g s t a t i o n s . T h e d i s c u s s i o n o f g r o u n d w a t e r i n f l u e n c e o n s t r e a m w a t e r q u a l i t y w i l l d r a w f r o m s e v e r a l s o u r c e s a n d i n c l u d e a g e n e r a l c o m p a r i s o n o f s u r f a c e w a t e r q u a l i t y a n d g r o u n d w a t e r q u a l i t y a n d h o w t h e s e m a y b e r e l a t e d , a s p e c i f i c l o o k at t h e w a t e r q u a l i t y i n t h e a r e a m e n t i o n e d a b o v e a n d r e f e r e n c e t o a p r e v i o u s s t u d y t h a t s p e c u l a t e d o n t h e s a m e p r o b l e m . T w o p a r a m e t e r s t ha t w e r e m e a s u r e d b o t h i n t h e s t r e a m s a n d g r o u n d w a t e r ( n i t r a t e a n d c o n d u c t i v i t y ) as w e l l as t e m p e r a t u r e ( w h i c h w a s o n l y m e a s u r e d i n t h e s u r f a c e w a t e r ) w i l l b e d i s c u s s e d a n d c o m p a r e d . 73 Figure 44. Area of sampling network where surface and groundwater interactions are most likely It i s w e l l k n o w n t ha t i n t he F r a s e r V a l l e y , m a n y s t r e a m s r e l y a l m o s t e n t i r e l y o n g r o u n d w a t e r f l o w t o m a i n t a i n t h e i r b a s e f l o w i n t h e s u m m e r ( W e r n i c k et al, 1 9 9 8 ) . I n H a t z i c i t w a s o b s e r v e d tha t at l e a s t o n e s t r e a m ( M a c N a b C r e e k ) a n d a s m a l l l a k e ( A l l a n L a k e ) w e r e s e a s o n a l i n n a t u r e ( s e e fig 6 i n s e c t i o n 2 . 4 . 2 f o r t h e l o c a t i o n o f t h e s e w a t e r b o d i e s ) . T h e s e b o d i e s o f w a t e r w e r e c o m p l e t e l y d r y f o r m u c h o f t he s a m p l i n g p e r i o d ( l a t e J u l y u n t i l O c t o b e r ) . A l l o t h e r s t r e a m s s a m p l e d c o n t i n u e d t o f l o w t h r o u g h o u t t h e s u m m e r s u g g e s t i n g tha t g r o u n d w a t e r w a s p r o v i d i n g s o m e r e c h a r g e t o t h e s e s t r e a m s at s o m e p o i n t i n t h e i r f l o w . It i s a s s u m e d tha t t h e i m p a c t s o f g r o u n d w a t e r r e c h a r g e o n s t r e a m c h e m i s t r y w i l l d e c l i n e as t he s t r e a m r u n s f u r t h e r f r o m t h e g r o u n d w a t e r s o u r c e . I n h i s 1 9 9 4 r e p o r t f o r J o h n C o n r o y a n d N e i g h b o u r s , D a k i n ( P i t e a u A s s o c i a t e s , 1 9 9 4 ) n o t e d tha t t h e r e i s a " p r o l i f i c s e r i e s o f s p r i n g s l o c a t e d . . . i n t he b a n k s o f t he u p p e r r e a c h e s o f D u r i e u C r e e k " . H e a l s o c o m m e n t e d " w e s u s p e c t t ha t p o r t i o n s o f B e l c h a r t o n c r e e k a n d t h e o t h e r s o u t h w a r d d r a i n i n g c r e e k s s u c h as D u r i e u C r e e k a r e f e d a l m o s t e x c l u s i v e l y b y d i s c h a r g e f r o m t h e d e e p c o n f i n e d a q u i f e r " . T h e a q u i f e r h e ' s r e f e r r i n g t o i s A Q 3 . M u c h o f t h i s a q u i f e r f l o w s s o u t h w a r d s ( P i t e a u A s s o c i a t e s , 1 9 9 4 , P H C L , 2 0 0 3 ) a n d b a s e d o n t h e p r o f i l e p r e s e n t e d i n c h a p t e r 3 ( f i g u r e 10 ) i t i s e a s y to i m a g i n e tha t t h e e d g e o f t h i s a q u i f e r c o u l d b e e x p o s e d i n t h e v i c i n i t y o f D u r i e u a n d t h e o t h e r c r e e k s w i t h t h e i r h e a d w a t e r s o n t h i s h i l l s i d e . T h e s o u t h e r n m o s t w e l l l o g i n p r o f i l e 3 ( o n t h e f a r r i g h t o f t h e d i a g r a m ) h a s a m u c h s h a l l o w e r l a y e r o f c l a y ( 2 0 m ) t h a n d o t he w e l l s l o g g e d f u r t h e r n o r t h ( o n t h e l e f t o f t h e d i a g r a m ) w h i c h h a v e c l a y l a y e r s 4 0 - 5 5 m t h i c k . F i g u r e 4 4 s h o w s t h e l o c a t i o n o f t h e s o u t h e r n m o s t l o g i n t h i s p r o f i l e o n t he t o p l e f t 74 c o m e r o f t h e m a p . T h i s l o c a t i o n i s o v e r 6 0 m h i g h e r t h a n t h e s u r f a c e o f t h e p r a i r i e . It f o l l o w s t ha t as t h e g r o u n d c o n t i n u e s t o s l o p e d o w n w a r d , t h e c l a y l a y e r w o u l d b e c o m e e v e r t h i n n e r u n t i l i t e v e n t u a l l y e x p o s e s t h e g r a v e l a n d s a n d o f t h e a q u i f e r i n t h e s i d e o f t h e h i l l . T h i s i s w h a t w a s o b s e r v e d b y D a k i n ( 1 9 9 4 ) w h o , w h e n v i s i t i n g t h e s p r i n g s n e a r t h e s o u r c e o f D u r i e u c r e e k r e m a r k e d t h a t " t h e s e s p r i n g s i s s u e f r o m a c o a r s e s a n d a n d g r a v e l u n i t w h i c h i s e x p o s e d i n t h e v a l l e y w a l l s a n d . . . i s d i s c h a r g i n g f r o m t h e d e e p c o n f i n e d a q u i f e r " . W e c a n , t h e r e f o r e , s p e c u l a t e t ha t t h e m o s t d i r e c t g r o u n d w a t e r i n f l u e n c e o n s u r f a c e w a t e r w i l l b e o c c u r r i n g i n t h o s e s t r e a m s tha t a re f e d b y d i s c h a r g e f r o m A Q 3 . T h e n e x t p r o b l e m i s t o d e t e r m i n e h o w t h i s g r o u n d w a t e r i s i n f l u e n c i n g t h e s t r e a m w a t e r q u a l i t y . I n s o m e c a s e s t h e i n f l u e n c e o f g r o u n d w a t e r o n s u r f a c e w a t e r i s o b v i o u s a n d i s m a n i f e s t e d a s a d e c l i n e i n s u r f a c e w a t e r q u a l i t y . T h i s i s t h e i l l u s t r a t e d o n t h e S u m a s P r a i r i e ( a n o t h e r a r e a i n t h e F r a s e r V a l l e y ) w h e r e o f a s h a r p i n c r e a s e i n s t r e a m n i t r a t e i n M a r s h a l l C r e e k i n d i c a t e d i s c h a r g e o f c o n t a m i n a t e d g r o u n d w a t e r f r o m t h e A b b o t s f o r d a q u i f e r ( B e r k a et ai, 2 0 0 1 , S m i t h ( p e r s c o m m . ) , 2 0 0 3 ) . I n t h e H a t z i c V a l l e y i t i s r e a s o n a b l e t o s p e c u l a t e tha t t h e o p p o s i t e i s t r u e . W e h a v e e s t a b l i s h e d i n p r e v i o u s s e c t i o n s t ha t t h e w a t e r q u a l i t y i n A Q 3 i s q u i t e g o o d a n d t h a t t h e r e a r e n o s i g n i f i c a n t s e a s o n a l f l u c t u a t i o n s o f m o s t p a r a m e t e r s m e a s u r e d i n c l u d i n g n i t r a t e a n d c o n d u c t i v i t y ( f o r w h i c h w e a l s o h a v e s t r e a m d a t a ) . T h e r e a r e , h o w e v e r , s i g n i f i c a n t d i f f e r e n c e s i n n i t r a t e l e v e l s as w e l l as c o n d u c t i v i t y l e v e l s i n t h e s a m p l e s o f s t r e a m w a t e r t a k e n t h r o u g h o u t t h e y e a r . T h e n i t r a t e l e v e l s i n t h e s t r e a m w e r e m u c h l o w e r i n t h e s u m m e r t h a n i n t h e w i n t e r ; i t f o l l o w s , t h e r e f o r e , t ha t i n t h e s u m m e r , t h e s t r e a m s a r e r e c e i v i n g l o w n i t r a t e g r o u n d w a t e r d i s c h a r g e f r o m t h e d e e p c o n f i n e d a q u i f e r . T h e s t r e a m n i t r a t e l e v e l s r i s e i n t h e w i n t e r w h i l e t h e g r o u n d w a t e r n i t r a t e l e v e l s r e m a i n m o r e c o n s t a n t ( e s p e c i a l l y i n t h e d e e p e r w e l l s i n A Q 3 ) . I n t h e w i n t e r t h e s u r f a c e w a t e r i s r e c e i v i n g m u c h m o r e i n p u t f r o m r a i n a n d s u r f a c e r u n - o f f w h i c h l i k e l y r a i s e s t h e l e v e l s o f n i t r a t e i n t h e s t r e a m s d i r e c t l y ( r a t h e r t h a n t h r o u g h g r o u n d w a t e r r e c h a r g e . ) A s i m i l a r p a t t e r n c a n b e s e e n w h e n c o m p a r i n g c o n d u c t i v i t y v a l u e s b e t w e e n g r o u n d w a t e r s a m p l e s a n d s u r f a c e w a t e r s a m p l e s . A g a i n , t h e c o n d u c t i v i t y v a l u e s o f t he g r o u n d w a t e r s a m p l e s d i d n ' t c h a n g e d r a m a t i c a l l y b e t w e e n w i n t e r a n d s u m m e r . H o w e v e r , t h e r e w e r e s i g n i f i c a n t d i f f e r e n c e s i n c o n d u c t i v i t y i n t h e s t r e a m s b e t w e e n t h e s e a s o n s . I n t h e s u r f a c e w a t e r c o n d u c t i v i t y w a s h i g h e s t i n s u m m e r . T h i s c a n b e a t t r i b u t e d i n l a r g e p a r t t o t h e f a c t t ha t t h e r e i s l e s s w a t e r i n m o s t s t r e a m s i n t h e s u m m e r a n d t h e r e f o r e d i s s o l v e d i o n s w i l l b e m o r e c o n c e n t r a t e d , g i v i n g h i g h e r r e a d i n g s . C o n d u c t i v i t y o f t h e g r o u n d w a t e r s a m p l e s w a s c o n s i s t e n t l y h i g h e r t h a n t ha t o f t he s u r f a c e w a t e r s a m p l e s b e c a u s e a s g r o u n d w a t e r t r a v e l s t h r o u g h t h e s u b s u r f a c e i t t e n d s t o p i c k u p d i s s o l v e d i o n s . It w o u l d , t h e r e f o r e , b e e x p e c t e d t ha t i f a m a j o r i t y o f t h e s t r e a m f l o w w e r e b e i n g p r o v i d e d b y g r o u n d w a t e r r e c h a r g e , t h i s s t r e a m w a t e r w o u l d h a v e h i g h e r c o n d u c t i v i t y . T h i s i s c o n s i s t e n t w i t h t h e o b s e r v a t i o n s , t h e s t r e a m w a t e r h a d h i g h e r c o n d u c t i v i t y l e v e l s i n t h e s u m m e r w h e n m o r e o f t h e f l o w w a s b e i n g p r o v i d e d b y d i r e c t g r o u n d w a t e r r e c h a r g e a n d 75 l o w e r v a l u e s i n t h e w i n t e r w h e n l o w e r c o n d u c t i v i t y r a i n w a t e r w a s d i l u t i n g t h e f l o w a n d p r o v i d i n g m o r e o f i t s v o l u m e . Figure 45. Clusters based on stream temperature (entire sampling period) A f i n a l p a r a m e t e r t ha t c a n i n d i c a t e t h e p r e s e n c e o f g r o u n d w a t e r d i s c h a r g e i s t e m p e r a t u r e . S t r e a m s t h a t a r e s t r o n g l y i n f l u e n c e d b y g r o u n d w a t e r t e n d t o h a v e m o r e s t a b l e t e m p e r a t u r e s a n d i n p a r t i c u l a r m a y h a v e c o o l e r w a t e r i n t h e s u m m e r t h a n t h e s u r r o u n d i n g a r e a s a n d w a r m e r w a t e r i n t h e w i n t e r ( W e r n i c k et al, 1 9 9 8 ) . A c l u s t e r a n a l y s i s w a s p e r f o r m e d u s i n g a l l t h e t e m p e r a t u r e d a t a i n o r d e r t o s e e i f t h e c l u s t e r i n g o f t h e t e m p e r a t u r e s u g g e s t s a n y g r o u n d w a t e r i n f l u e n c e . T h e r e s u l t s ( s h o w n o n f i g u r e 4 5 ) s h o w t h r e e c l u s t e r s . C l u s t e r o n e i n c l u d e s s t a t i o n 8 , 9 a n d 1 0 , c l u s t e r 2 s t a t i o n s 2 , 4 , 5 , 6 , 1 l , 1 2 , a n d 1 3 , a n d t h e final c l u s t e r i n c l u d e s t h e r e m a i n i n g s t a t i o n s . 76 emp Dry Season Avg. ZfTemp Wet Season Avg. i i T h e e x i s t e n c e o f c l u s t e r o n e f u r t h e r c o n f i r m s t h e h y p o t h e s i s t ha t g r o u n d w a t e r i s i n f l u e n c i n g s t a t i o n s 8 , 9 a n d 1 0 , a t l e a s t f o r p a r t o f t h e y e a r . I n o r d e r t o tes t s t r e n g t h o f t h e c l u s t e r s a K r u s k a l - W a l l i s -t es t w a s r u n o n a l l t h e t e m p e r a t u r e d a t a u s i n g t h e c l u s t e r s as g r o u p s . T h e r e s u l t s s h o w e d t ha t t h e r e w e r e s i g n i f i c a n t d i f f e r e n c e s b e t w e e n t h e t e m p e r a t u r e s o f a t l e a s t o n e o f t h e c l u s t e r s f o r m o s t o f t h e s u m m e r m o n t h s ( w i t h t h e e x c e p t i o n o f d a t a f r o m J u l y 2 4 , w h e n m o s t s t a t i o n s h a d h i g h e r t h a n n o r m a l t e m p e r a t u r e s ) . W h e n t h e M a n n -W h i t n e y U t es t w a s u s e d t o d e t e r m i n e w h i c h o f t h e s a m p l e s w e r e d i f f e r e n t f r o m e a c h o t h e r i t w a s f o u n d tha t c l u s t e r 1 w a s s i g n i f i c a n t l y d i f f e r e n t t h a n c l u s t e r 2 o n l y i n J u l y , A u g u s t , S e p t e m b e r a n d O c t o b e r , t h e t i m e o f y e a r w e e x p e c t t h e s e s t r e a m s t o b e m o s t d e p e n d e n t o n g r o u n d w a t e r f o r r e c h a r g e . T h e o t h e r c l u s t e r s w e r e d i f f e r e n t f r o m e a c h o t h e r at a l m o s t a l l t i m e s o f t h e y e a r . T h e d i f f e r e n c e s b e t w e e n c l u s t e r 2 a n d 3 a r e l i k e l y r e l a t e d t o d i f f e r e n c e s i n l a n d c o v e r , as a r e t h e d i f f e r e n c e s b e t w e e n c l u s t e r s 1 a n d 3 . _ 22 O <D Q. 16 E l — 14 12 10 8 6 Cluster 1 Cluster 2 Cluster 3 Figure 46. Temperature Cluster Boxplots 4.7.1 Surface Water Impacts on Groundwater Quality T h e i n f l u e n c e o f s u r f a c e w a t e r o n g r o u n d w a t e r i n t h e H a t z i c V a l l e y i s d i f f i c u l t t o d e t e r m i n e b e c a u s e o f t h e s p o r a d i c n a t u r e o f h i g h n i t r a t e w e l l s . It c a n b e a s s u m e d t ha t t h e w e l l s w i t h h i g h n i t r a t e t ha t a r e n o t o n H a t z i c I s l a n d ( i . e . a r e n o t i m p a c t e d b y s e p t i c s y s t e m s - w h i c h i s l a r g e l y s u b s u r f a c e i m p a c t ) m a y b e u n d e r l o c a l i n f l u e n c e o f s u r f a c e w a t e r . I f a n y o f t h e s e w e l l s a r e n o t c o n s t r u c t e d p r o p e r l y i t i s l i k e l y t ha t c o n t a m i n a t e d r u n - o f f m a y b e e n t e r i n g t h e s e w e l l s . I n g e n e r a l , h o w e v e r , t h e s t r e a m d a t a s e e m t o s u g g e s t t ha t t h e s u r f a c e w a t e r d o e s n o t i m p a c t t he g r o u n d w a t e r q u a l i t y . T h e n i t r a t e v a l u e s m e a s u r e d i n t h e s t r e a m s w e r e g e n e r a l l y q u i t e l o w , m e a n i n g t ha t t h e y w o u l d n o t b e a s o u r c e o f n i t r a t e t o t h e s t r e a m s . I n o r d e r t o c o m e t o m o r e d e f i n i t i v e c o n c l u s i o n s a b o u t t he g r o u n d w a t e r a n d s t r e a m w a t e r i n t e r a c t i o n s m o r e d e t a i l e d h y d r o l o g i c a l i n v e s t i g a t i o n s w o u l d h a v e t o b e c a r r i e d o u t . T h i s m o n i t o r i n g c o u l d i n c l u d e p r o c e d u r e s s u c h as i n s t a l l a t i o n o f s e e p a g e m e t e r s ( L e e a n d C h e r r y , 1 9 7 8 ) , u s e o f i s o t o p e s , m o r e d e t a i l e d t e m p e r a t u r e a n d c o n d u c t i v i t y p r o f i l i n g a l o n g t h e e n t i r e l e n g t h o f t h e s t r e a m ( O x t o b e e a n d N o v a k o w s k i , 2 0 0 2 ; H i n t o n et al., 1 9 9 3 ) o r t a k i n g I C P m e a s u r e m e n t s f o r t h e s t r e a m s a m p l e s ( B e c k i e , p e r s c o m m . , 2 0 0 3 ) . H o w e v e r w i t h t h e i n f o r m a t i o n at h a n d w e c a n m a k e e d u c a t e d s p e c u l a t i o n t h a t t h e g r o u n d w a t e r h a s a s u b s t a n t i a l i n f l u e n c e o n t h e f l o w o f B e l c h a r t o n , D u r i e u , O r u C r e e k a n d S e u x B r o o k d u r i n g t h e d r y 77 season (especially between July and October) and that this influence is less evident during the wet season (November to March). 4.8 Survey Results and Discussion Most of the households who supplied groundwater samples also completed a questionnaire (see appendix 5 for survey questions). Ninety-seven percent of those given a survey returned it. Not all surveys handed back were complete; therefore, "n" is variable for each question. The survey results will be presented as follows. First, the responses to specific questions are given, this is followed by a discussion of the relationships between the questions and the water quality parameters, regional variation in responses to specific questions are also examined, and the final section is a discussion the perceptions vs. the analytical reality. 4.8.1 General Responses 4.8.1a Water Quality Perception The majority of residents in the Hatzic Valley (79%) perceive their water quality as being excellent or good. Table 19 outlines the residents' water quality perceptions. Table 19. Responses to "What is your perception of the water quality from your well?" Excellent Good Moderate Fair Poor Percentage 43% 36% 9% 7% 4% Number 32 27 7 5 3 It is known that members of the public often base their perceptions of risk or of water quality on different metrics than 'experts' (Scherer, 1990). Figure 47 shows measures of "intuitive toxicology" (Kraus et al., 1992) that people might use to discern if water quality is "good" or not. The figure shows the importance of these measures for residents of the Hatzic Valley. 78 Illness in community Quality of nearby water Particulate Matter in Glass Depth of Water Table Abnormalities Colour Cloudiness Smell/Taste 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% • Most Important • Important • Important • Less important m Less Important • Not Important • Least Important Figure 47. Responses to the quest ion "How important are the fo l lowing as a guide for indicating the quality of your water?" P e o p l e a r e m u c h m o r e l i k e l y t o r e l y o n t a n g i b l e i n d i c a t o r s o f w a t e r q u a l i t y t o f o r m t h e i r p e r c e p t i o n s o f q u a l i t y , t ha t i s t h o s e p a r a m e t e r s t h e y c a n e a s i l y t a s t e , s m e l l o r s e e . A s f i g u r e 4 7 s h o w s , s m e l l a n d tas te w a s a n i m p o r t a n t i n d i c a t o r o f w a t e r q u a l i t y t o j u s t o v e r 6 0 % o f r e s p o n d e n t s f o l l o w e d c l o s e l y b y v i s i b l e a b n o r m a l i t i e s i n t h e w a t e r . M a n y r e s i d e n t s s a w q u a l i t y o f n e a r b y w a t e r a n d d e p t h t o t h e w a t e r t a b l e as l e s s i m p o r t a n t . 4.8.1b Water Sources R e s i d e n t s w e r e a s k e d s e v e r a l s u r v e y q u e s t i o n s tha t p e r t a i n e d t o t h e i r s p e c i f i c s o u r c e s o f w a t e r a s w e l l a s m o r e g e n e r a l q u e s t i o n s a b o u t w h i c h l a n d u s e a c t i v i t i e s c o u l d a d v e r s e l y a f f e c t t h e i r w a t e r s o u r c e s a n d h o w w a t e r s o u r c e s s h o u l d b e s t b e m a n a g e d . W h e n a s k e d , " d o y o u t h i n k a n i n c r e a s e i n g r o u n d w a t e r a q u i f e r u s e i s a p p r o p r i a t e ? " S e v e n t y o n e p e r c e n t o f r e s p o n d e n t s f e l t t h e y n e e d e d m o r e i n f o r m a t i o n . T h i s r e s p o n s e h i g h l i g h t s t h e l a c k o f k n o w l e d g e a b o u t t h e g r o u n d w a t e r r e s o u r c e i n t h e H a t z i c V a l l e y a n d t h e n e e d f o r t e c h n i c a l i n v e s t i g a t i o n s t o d e t e r m i n e t h e e x t e n t o f t h e r e s o u r c e . A q u e s t i o n r e g a r d i n g l a n d u s e a s k e d , " H o w i m p o r t a n t i s e a c h o f t h e f o l l o w i n g a c t i v i t i e s i n c a u s i n g w a t e r q u a l i t y p r o b l e m s ? " T h e r e s p o n s e s a r e p r e s e n t e d i n f i g u r e 4 8 . I n g e n e r a l , o v e r 5 0 % o f r e s p o n d e n t s f e l t t ha t c h e m i c a l s f r o m f a r m i n g , m a n u r e f r o m f a r m i n g , i n d u s t r i a l a c t i v i t y a n d f e r t i l i z e r f r o m f a r m i n g w e r e v e r y i m p o r t a n t i n c a u s i n g w a t e r q u a l i t y p r o b l e m s . A g g r e g a t e e x t r a c t i o n w a s c o n s i d e r e d v e r y i m p o r t a n t 7 9 b y 4 7 % o f r e s p o n d e n t s a n d s e p t i c s y s t e m s b y o n l y 4 5 % o f r e s p o n d e n t s . Aggregate Extract ion Industrial activity Sept ic s y s t e m s Golf c o u r s e management L a w n ferti l ization Hobby fa rms Farming (chemicals) Farming (manure) Farming (fertilizer) 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Percentage of respondants I Very Important • Important I Moderately important • L e s s Important • Moderate ly important • Not Important Figure 48. Response to the quest ion "How important are these activit ies in caus ing water quality p rob lems?" F o l l o w i n g t h e q u e s t i o n s a b o u t t he i m p o r t a n c e o f c e r t a i n a c t i v i t i e s i n c a u s i n g w a t e r q u a l i t y p r o b l e m s p a r t i c i p a n t s w e r e a s k e d f o r o p i n i o n s a b o u t t he a p p r o p r i a t e n e s s o f v a r i o u s m a n a g e m e n t t e c h n i q u e s f o r m a n a g i n g g r o u n d w a t e r r e s o u r c e s ( s h o w n i n f i g u r e 4 9 ) . P e o p l e f e l t t h e m o s t i m p o r t a n t s t r a t e g y w o u l d b e to l i m i t i n d u s t r i a l d e v e l o p m e n t , 5 8 % f e l t t h i s w a s v e r y i m p o r t a n t . R e s t r i c t i o n s o n m a n u r e a l l o c a t i o n s a n d f e r t i l i z e r a p p l i c a t i o n s w e r e s e e n as b e i n g v e r y a p p r o p r i a t e s t r a t e g i e s b y 4 7 % a n d 5 0 % o f r e s p o n d e n t s r e s p e c t i v e l y . I n a d d i t i o n t o q u e s t i o n s a b o u t s p e c i f i c s t r a t e g i e s f o r m a n a g i n g g r o u n d w a t e r , p a r t i c i p a n t s w e r e a s k e d i f t h e y f a v o u r e d v o l u n t a r y , r e g u l a t o r y o r a c o m b i n a t i o n o f b o t h s t r a t e g i e s f o r m a n a g i n g g r o u n d w a t e r r e s o u r c e s . S i x t y - f o u r p e r c e n t o f r e s p o n d e n t s f a v o u r e d a m i x t u r e o f r e g u l a t o r y a n d v o l u n t a r y i n i t i a t i v e s . 80 Restrict urban development Restrict industrial development Regulate land use Introduction of a municipal sewer system Control road runoff Septic system regulations Restrict lawn & garden use of chemicals Restrictions on manure applications Restriction on fertilizer use in agriculture 0% 20% 40% 60% Percentage of respondants. 80% 100% • Extremely Appropriate • Extremely Appropriate • Moderate • Moderate • Not appropriate • Not Appropriate Figure 49. Responses to the quest ions "How appropriate do you think the fo l lowing strategies are for managing groundwater resources" A final q u e s t i o n t ha t r e l a t e d d i r e c t l y t o k n o w l e d g e o r o p i n i o n o f g r o u n d w a t e r s o u r c e s w a s i n t e n d e d to g a u g e k n o w l e d g e a b o u t i n t e r a c t i o n s b e t w e e n g r o u n d w a t e r a n d s t r e a m w a t e r . P a r t i c i p a n t s w e r e a s k e d , " T o w h a t e x t e n t d o y o u t h i n k u s e o f t h e g r o u n d w a t e r a q u i f e r a f f e c t s t h e l o c a l r i v e r s ? " T h e b r e a k d o w n o f r e s p o n s e s i s f o u n d i n t a b l e 2 0 . I n g e n e r a l m o s t r e s p o n d e n t s w e r e a w a r e tha t g r o u n d w a t e r a n d s t r e a m w a t e r i n t e r a c t w i t h e a c h o t h e r . Table 20. Groundwater Impact on Local Rivers Signif icant Impact Some mpact No Impact River F low n=17 27.4% n=29 46.7% n=16 25.8% Water Quali ty n=24 38.7% n=22 35.5% n=16 25.8% 4.8.1c Treatment S e v e r a l q u e s t i o n s w e r e a s k e d a b o u t t h e t r e a t m e n t p r a c t i c e s o f w e l l o w n e r s i n t h e H a t z i c w a t e r s h e d . U n t i l r e c e n t l y t h e r e w e r e n o r e q u i r e m e n t s f o r g r o u n d w a t e r t r e a t m e n t a n y w h e r e i n 8 1 British Columbia. However, the recently amended Drinking Water Protection Regulation requires that, ".. . drinking water from a water supply system must be disinfected if the water originates from (a) surface water, or (b) ground water that, in the opinion of a drinking water officer, is at risk of containing pathogens"(emphasis mine) (B.C. REG200/2003). This section of the regulation does not apply to the individual wells that supply water to most residents of the Hatzic Valley. According to the survey results very few residents of the Hatzic Valley treat their water. We asked questions about filtration and other treatment practices and found that although 86% of those surveyed drink the water from their wells most people in the valley do not filter their water or treat it in any other way. Thirty-two percent of respondents filter their water and only 7% percent treat their water in any other way. Additionally 15% of respondents always or often drink bottled water at home as opposed to 65% who never do. A remaining 20% sometimes drink bottled water at home. 4.8. Id Monitoring When asked about monitoring, only 12 % of respondents were found to have tested their well once a year or more than once a year. Fourteen percent tested their water every 2 to 3 years. Forty percent said "other", which is assumed to mean less frequently than every three years. Six percent said they had tested their well once when drilled and 28% never tested their well. It is assumed, therefore, that 74% of participants test their wells very infrequently. Most community water systems are required to test their water much more frequently than once per year and of the respondents who sample their water more than once a year, one sells bottled water from their spring and the others are community water systems that serve multiple households and are likely regulated to do use. Table 21. Frequency of Chemical and Biological Testing Frequency Number Percent More than once a year 4 6% Once a year 4 6% Every 2 years 3 4% Every 3 years 7 10% Other 28 40% Tested when drilled 4 6% Never Tested 20 28% 4.8.2 Regional Variation in Survey Response There was no correlation between perceptions of water quality and location; people living on A Q l were just as likely as people living on AQ3 to feel their water quality was excellent or good. Despite similar perceptions of water quality there was a significant correlation (r = 0.344 at a 0.01) between location and 82 whether the residents filtered their water or not; those living on A Q l are more likely to filter their water than those living on the other aquifers (see table 22 for details). Table 22. Cross-tab: Location vs. Filtration. Do you filter your well water? Total Yes No Location AQl 13 (54%) 11 24 AQ2 6(31%) 12 19 AQ3 5 (16%) 26 31 Total 24 50 74 When looking at the measures of intuitive toxicology there was a significant correlation between location and the importance of smell and taste as a water quality indicator (r = -0.371 at a 0.01). These factors were less important to people surveyed from A Q l (47% rated it as most important) than from AQ2 (64%) or AQ3 (83%). Other factors such as visible abnormalities in the water, colour and cloudiness and the presence of particulate matter in the glass were also seen as being quite important indicators throughout the watershed but of these; cloudiness (r = -0.249), colour (r = -0.285), visible particulate matter in the glass (-0.277) and incidence of gastrointestinal illness in the community (r = -0.247) were also significantly correlated with location (all at a 0.05). In all cases the indicators were more important to people who lived on AQ3 than to those living on A Q l . The importance of the depth to the water table as an indicator of water quality also had regional variation in the responses (r = -0.326, a 0.01). Table 23 shows that depth to the water table is a more important indicator of water quality for residents of AQ3 that for those who live on A Q l . This is interesting because the residents of A Q l have significantly shallower wells than the residents of AQ3. Perhaps residents of A Q l place less importance on water table depth as an indicator of water quality because they have no choice but to have shallower wells. Table 23. Cross-Tab: Location vs. depth to water table How important is depth of water table as a guide for indicating the quality of your water? Total Very Important Somewhat Important Not Important Aquifer AQl 8 (40%) 11 1 20 AQ2 9 (60%) 3 3 15 AQ3 21 (72%) 6 2 29 Total 38 20 5 64 People from different parts of the aquifer placed different levels of importance on different land use activities. There was a significant positive correlation between aggregate extraction and location (r = 0.0419 at a 0.01). This activity was seen as more important by residents in the north of the valley where, as mentioned in chapter 3, there is local controversy over the development of a quarry. Table 24 shows the breakdown of the responses to this question based on aquifer. Likely related to this is that industrial 83 activity was also seen as a bigger problem by people from AQ3 than from AQ1 or AQ2 (correlation coefficient 0.308 at a 0.05). Table 24. Cross-tab: Location vs. aggregate extraction How important is aggregate extraction in causing water quality problems? Total Not important Moderately Important Extremely Important Location AQ1 4 9 8 (38%) 21 AQ2 3 4 7 (50%) 14 AQ3 0 5 22 (81%) 27 Total 7 18 37 62 4.8.2a Septic Systems In rural areas one of the potential point sources of groundwater contamination is septic systems (Jaffe and DiNovo, 1987) and as discussed previously septic systems are the likely source of nitrate contamination on Hatzic Island. When working properly septic systems are effective at treating waste generated by individual homes, however service and proper siting are essential to maintain well functioning septic systems. Everyone surveyed had a private septic system with which to treat his or her household waste. However, opinions about how important septic systems are in causing water quality problems and the appropriateness of potential solutions show the greatest regional variation of all issues. The first regional difference was seen in the responses to the questions about how important septic systems were in causing water quality problems. The responses to this question were significantly correlated with location (r = -0.304 a 0.05). Residents of AQ1 thought that septic systems were a much more important factor in causing water quality problems than did the residents of the other two aquifers. Table 25. Cross-tabs: Location vs. Importance of Septic Systems How important are septic systems in causing water quality problems? Total Not Important Moderately Important Extremely Important Location AQ1 1 2. 19(86%) 22 AQ2 6 4 8 (57%) 14 AQ3 3 8 15(57%) 26 Total 6 14 24 62 When asked about which strategies were most appropriate for managing groundwater resources opinion on strategies that related to septic systems also differed between aquifers. There was a significant negative correlation between location and response to the question "how appropriate do you think the introduction of septic system monitoring and servicing regulations is for managing groundwater resources" (r = -0.273 at a 0.05). Slightly more residents from the south of the valley found this appropriate than those from the north. The question with the largest split in opinion was, "How 84 appropriate do you think the introduction of a municipal sewer system is for managing groundwater resources." Sixty-eight percent of respondents from A Q l felt this was a very appropriate strategy whereas 45% of respondents from AQ3 felt it was very inappropriate. The responses are presented in table 26. The responses for this question were significantly correlated with location (r = -0.322 at a 0.05). Table 26. Cross-tabs: Location vs. Sewer System Installation Is the introduction of a municipal sewer system an appropriate strategy for managing groundwater resources? Total Not Appropriate Moderately Appropriate Extremely Appropriate Location A Q l 6 1 15 (68%) 22 AQ2 3 5 4 (33%) 12 AQ3 11 (45%) 8 5 (20%) 24 Total 20 14 24 58 Some of the reasons for these discrepancies in response can perhaps be explained by the breakdown of the responses to the question "How close is your septic system to your well?" As with the previous questions related to septic systems there is a significant correlation between the responses to this question and location (correlation coefficient 0.291, a 0.05). Sixty-one percent of those living on A Q l reported their septic systems as being between 0 and 30 metres from their well as opposed to only 17% of residents of AQ2 and 25% of those living on AQ3. In contrast, 44% of people from AQ3 reported their septic system as being farther than 50 m from their well. Finally, residents were asked questions about how frequently they serviced their septic systems. Very few residents serviced their systems more frequently than every five years. The residents of A Q l serviced their systems much more frequently than people living on the other aquifers (r = 0.251 a 0.05). Eighty percent of those living on A Q l service their septic systems between 1-5 years as opposed to only 37% of AQ2 residents and 55% of AQ3 residents who do the same. These results suggest that although the residents of A Q l are more concerned about their septic systems being a possible cause of groundwater contamination because of the proximity to their wells to their septic systems than residents of the other aquifers they are also trying to minimize the risks of contamination from their septic systems by servicing them slightly more frequently. In AQ3, where septic systems are farther away from homes and wells there is less potential for contamination from these sources and therefore they cause less concern. 4.8.3 Other Correlations As mentioned above, most of the residents of the Hatzic Valley perceive their water quality as being good or excellent. There is a positive correlation between people's perception of their water quality and whether or not they drink their water (r = 0.528, a 0.01). Those with good perception of their drinking water are also less likely to drink bottled water at home (r = 0.397 at a 0.01), of the 8 people who rated their water quality as fair to poor, five (63%) always drink bottled water at home whereas 45 of the 59 8 5 people (76%) who perceive the quality of their water as excellent never drink bottled water at home. There is a small but significant positive correlation between water quality perception and those who have had chemical or bacterial exceedances in their well water (r = 0.258, a 0.05); people are more likely to have a negative impression of their water quality if they have previously exceeded the water quality guidelines. There was no correlation between frequency of monitoring and perception of water quality nor was there any correlation between the perception of quality and whether people filter their water. Twenty people who felt they had excellent water quality filtered their water while 39 did not (as mentioned above incidence of filtration did relate to aquifer location - which is also not related to water quality perception). See table 27 for the numbers of people who filtered their water and those who do not compared with water quality perceptions. Table 27. Cross-Tab: Water Quality Perception vs. Filtration Do you Filter your well Water? Total Yes No What is your perception of Excellent-Good 20 39 59 your water quality? Moderate 1 6 7 (grouped into 3 ranks) Fair-Poor 3 5 8 Total 24 50 74 4.8.2a Water Quality Perception and Chemical Parameters As mentioned previously, the majority of residents of the Hatzic Valley, regardless of the aquifer they live on, perceive their water quality as being excellent or good. The water quality analysis done for this study confirms these perceptions. Interestingly correlations between water quality perception and the chemical parameters measured showed that those who perceived their water quality as poor were more likely to have higher levels of iron (r = 0.417 at a 0.01) or manganese (r = 0.252 at a 0.05) in their water (see table 28). There was no correlation between nitrate levels and water quality perception. Of the people with nitrate levels above 3 mg/L only one participant ranked their groundwater quality less than good. Both of the well owners who had nitrate above the health standards perceived their water quality as excellent and remarked that they always drank their well water. 86 Table 28. Spearman's Correlation (r): Drinking Water Perception NO3-N Cu Fe Mn Do you Drink you well water? Do you filter your well water? Do you treat your well water another way Perception of water quality NO3-N 1 Cu .216 1 Spearman's rank correlation coefficient (**) = Significant at a 0.01 Fe -.022 .111 1 (*) = Significant at a 0.05 Mn -.210 -.033 .553(**) 1 Do you drink your well water? -.049 -.124 .145 .206 1 Do you filter your well water? -.063 .080 -.088 -.031 .026 1 Do you treat your well water another way? .274(*) -.010 -.070 .020 -.133 .368(**) 1 Perception of water quality -.161 -.032 .417(**) .252(*) .512(**) -.044 -.314(**) 1 Based on the results of chemical testing and the survey responses it is evident that the residents are basing their water quality perceptions largely on tangible (intuitive) indicators of water quality rather than on the results of chemical analysis. Nitrate, a parameter with negative health implications, is tasteless and odourless. Iron and manganese, on the other hand, are visible nuisance parameters in tap water when present at high enough concentrations, that is, their presence can be discerned without sending water samples to a laboratory for analysis. The basing of perceptions on tangible indicators of groundwater quality is not surprising as the survey revealed that most residents test their groundwater infrequently. Many water quality problems such as elevated levels of coliforms and other pathogens can also only be detected through laboratory analysis. By not testing well water more frequently and basing perception of water quality only on tangible indicators residents may be exposing themselves to potential health hazards. 87 5.0 Summary and Conclusions The objectives of this project were to determine the quality of drinking water in the Hatzic Valley (with a focus on groundwater quality), investigate the links between groundwater, surface water and land use, to find out how local residents perceive their water quality and to compare the scientific results with those perceived by the residents. Field research was conducted in the Hatzic watershed in British Columbia's Lower Fraser Valley. Groundwater samples were taken from drinking water wells with the help of local residents. The water quality was determined for 75 wells that were sampled in July 2002 and again in March 2003. Surface water samples were collected at 19 stations on a semi-monthly basis between May 2002 and May 2003. A land use database was created using a GIS and the percentages of the four predominant land uses (forest, agriculture, rural residential and urban) were calculated within 50, 100 and 200 m radii of the wells sampled and within 100 m of the streams sampled. The perceptions and opinions of local residents were collected through a survey questionnaire that was collected at the same time as the water samples. Non-parametric statistical techniques were used to link the three types of data. 5.1 Summary The results show that the groundwater quality is relatively good based on the parameters measured in this study. Of the 75 groundwater wells tested, only 2 (2.6%) had nitrate levels above the GCDWQ standard of 10 mg/L nitrate-N and 12 (16% - including the 2 mentioned above) had nitrate-N values above 3 mg/L (the level which is generally considered to be an indicator of land use impacts). Several other wells were above the G C D W Q for aesthetic objectives such as iron and manganese. These compounds are a nuisance in water, but they do not represent a direct threat to human health. 5.1.1 Differences between Aquifers It was discovered early in the research that the study area encompassed three distinct aquifers. The results of significance testing showed that the chemistry of AQ1 (the southernmost aquifer) is significantly different based on Si, Ca, Mg, Sr, PO4 and Na than that of AQ2 and AQ3. The difference in water quality between AQ2 and AQ3 is not as pronounced and it may be that these aquifers have similar substrates or that the water from AQ3 flows south towards AQ2 and that these two aquifers are part of a continuous flow system. In addition to the three main aquifers it was determined that four wells in the region tap into a deep regional aquifer system with highly saline water. These wells had abnormally high conductivity (up to two orders of magnitude higher than the majority of wells sampled) as well as high levels of many other parameters. Although these wells are located on AQ2 they have chemistry unique from the other shallower wells sampled on this aquifer. Another local anomaly, shallow wells on AQ3, likely tap into small perched aquifers that are dispersed among the thick clay/till aquitard that confines the main aquifer in this area. 88 5.1.2 Nitrate and Depth There was a strong relationship between nitrate level and depth. The wells that had nitrate levels higher than 3 mg/L were all shallow wells, less than 12 m deep. The only wells with a change in nitrate level more than 1 mg/L between winter and summer were also less than 12 m deep. These two relationships highlight how important the depth of the wells is in determining nitrate levels. Shallower wells appear to be more prone to contamination from surface sources than deeper wells. No other parameters showed similar relationships with depth suggesting that the nitrate levels are related to human activity whereas the levels of other parameters are not. 5.1.3 Nitrate and Land Use. Significant negative correlations were found between nitrate levels and the percentage of forest surrounding the wells and significant positive correlations were found between nitrate levels and the percentage of urban land surrounding the wells. A significant relationship between nitrate in groundwater and agriculture was not seen despite the fact that this relationship has been observed elsewhere in the Lower Fraser Valley. The likely source of nitrate in the urban areas is septic systems. On Hatzic Island, especially, the water table is high at some points in the year, which may impede the proper functioning of septic systems causing nitrate to leach into the groundwater. The results show that the wells at most risk of nitrate contamination are shallow wells (<12 m) in urban areas. 5.1.4 Surface Water Conditions. The water quality in the streams appears good based on the parameters measured. Nitrate levels at all stations were below 3 mg/L throughout the sampling period. However, it should be kept in mind that the stream sampling was limited to a few nutrients and did not include metals or sediment sampling. For the parameters that were measured, the following trends were seen. As expected, temperature and conductivity were higher in summer than in winter. Both of these parameters tended to increase throughout the length of the watershed. Locally high levels of conductivity were seen in the upstream areas of some of the tributaries and diluted further downstream were also seen. Nitrate, on the other hand, increased in the winter (especially in November) and decreased in the summer. The highest stream nitrate levels were recorded at station 13; the levels decreased further downstream due to dilution from other tributaries. 5.1.5 Land use impacts on surface water quality Significant relationships were seen between land use and 1) conductivity and 2) temperature. Stream temperature was lower when a greater percentage of the stream reach was forested and higher in the stream reaches with greater percentages of agricultural land. This relationship was repeated for conductivity. Because the headwaters of the streams are in granitic rocks and the lower reaches of the 89 stream flow through areas where parent material is predominantly sand and gravel, the higher conductivity that was seen in the downstream reaches is likely due to the change from forested land to agricultural activity rather than geological factors. These results show that the land use in the Hatzic Valley influences the water quality in the streams that run through the valley. The impact of agriculture on nitrate levels was only seen locally whereas significant correlations between temperature and conductivity and amount of agricultural or forested land were seen throughout the watershed, suggesting that there are cumulative impacts from the changing land use, which is increasingly agricultural as one moves downstream. 5.1.6 Groundwater and Surface Water Interactions Based on the information available about the stream water and groundwater it seems likely that the streams in the vicinity of Durieu Road (stations 8-10) are directly recharged by groundwater in the summer. The water at these stations is cooler in summer and has higher conductivity than that measured at surrounding stations, suggesting that groundwater accounts for a significant portion of base flow in these areas. Since the nitrate in the streams was lower in summer than in winter this suggests that groundwater does not contaminate streams in the Hatzic Valley as it does in other areas of the Lower Fraser Valley. Throughout the valley, direct relationships between surface water and groundwater cannot be seen; however, since a strong relationship exists between levels of nitrate in groundwater and depths of wells it is assumed that land based sources of nitrate are impacting these shallow wells. Flooding is a problem in the Hatzic Valley and could cause negative impacts on groundwater if surface water is able to back-flow into wells during times of high water. In the area of Hatzic Island the water table is very high. It is likely that there is continuous interaction between lake water and groundwater in this area. 5.1.7 Perceptions The majority of the residents of the Hatzic valley perceive their water quality to be good to excellent. Water quality testing revealed that in general, water quality through the valley could be classified as good to excellent meaning that most residents were not wrong in their perceptions. These perceptions were significantly correlated with levels of iron and manganese measured in the water. Those with poor opinion of their water quality were more likely to have high levels of these two elements. Iron and manganese are nuisance chemicals in water that produce unpleasant taste as well as staining of fixtures and laundry. Nitrate, which was not correlated with water quality perception, is tasteless and odourless. Since most residents test their drinking water infrequently it is, perhaps, not surprising that water quality 90 perceptions were partly based on a tangible parameter such as iron rather than on an invisible one like nitrate. Regional differences were seen in many of the survey answers with residents from AQ3 placing greater emphasis on the importance on the various measures of "intuitive toxicology" than those who lived on A Q l . The residents of A Q l (which includes Hatzic Island) were also far more concerned about the effects of septic systems on water quality than those who lived elsewhere. As water quality testing showed clear correlations between nitrate levels and percentage of urbanisation surrounding wells it seems that the concerns of those living on A Q l are not unfounded. However the opinions of those living on AQ3 are also valid given that those living on A Q l are more likely to have their septic systems located within 30 m of their wells than those who lived in other parts of the valley. Sixty-eight percent of those living in the south of the valley felt that the introduction of a municipal sewer system would be a very appropriate measure to safeguard water quality while 45% of those living on AQ3 felt this strategy was extremely inappropriate. Again, the differences in housing density in these two areas probably explain the differences in the responses making neither opinion invalid. 5.2 Recommendations 5.2.1 Hatzic Island The majority of wells with high levels of nitrate were located in urban areas on Hatzic Island. Further testing of wells for nitrate and pathogens on the island is recommended to determine the extent of groundwater contamination in this area. If further sampling reveals widespread areas of nitrate contamination steps will need to be taken to try and alleviate the problem. Local solutions should be attempted before in implementation of large new infrastructure in the area. Homeowners should ensure they are servicing their septic systems on a regular basis as well as ensuring that individual wells are properly constructed and sealed. If these preventive measures are not sufficient to improve groundwater quality the FVRD may have to consider alternate sources of drinking water or sewage treatment for the island. Some of the options that should be considered to improve the quality of drinking water on Hatzic Island include the following, development of centralized sewage collection, piping in treated drinking water from a nearby municipality, providing local residents with bottled water for domestic consumption, or installation of point of use treatment for residents with contaminated water. Many of these options will be much more expensive than the status quo and it is beyond the scope of this project to complete a full cost benefit analysis and offer a conclusive recommendation. In considering options to improve drinking water quality on Hatzic Island the following factors must be considered: 1. Will the quality of water improve? 2. Will there be impacts on the ecosystem (i.e. Hatzic Lake) from the action? 3. What is the initial and long term cost of the action? 91 It should be remembered that while the quality of water from several of the wells on Hatzic Island is of concern, it is relatively good compared to the water found in other aquifers in the Lower Fraser Valley where nitrate levels as high as 45 mg/1 have been recorded (Carmichael et al., 1995) 5.2.2 Other Impacted Wells All of the wells with high nitrate levels were shallower than 12 m. Although many of the high nitrate wells were concentrated in the urban areas in Hatzic Island others, (including the well with the highest nitrate value in summer) are located throughout the valley in areas with different land uses. Studies in other parts of the L F V have linked elevated nitrate with agricultural activities. Although agriculture does not appear to have a widespread impact on the groundwater quality in the Hatzic valley it is recommended that homeowners with shallow wells monitor their wells more frequently for nitrate and pathogens (total and fecal coliforms) regardless of the land-use surrounding their well. If agricultural activity in the valley intensifies in the future more widespread nitrate contamination may be seen. Special attention should be paid to shallow wells on AQ1 in the area just east of Hatzic Island, as this is where the second greatest concentration of wells with nitrate levels above 3 mg/L was seen. It may be appropriate to include this area in any long term plans for alternate drinking water delivery that are developed for Hatzic Island. 5.2.3 Other Factors Influencing Water Quality Although not discussed in this project, it is known that the Hatzic Valley is prone to flooding and slope instability. These issues have been discussed at length in many government and consultant reports (these are summarized by Hogan (2001)). The instability and flooding will have implications for any future groundwater management options. Flooding is of special concern for groundwater quality as wells can become contaminated during periods of high water by direct surface water influence on the wells (flooding of the town's water supply was directly linked to the contamination in Walkerton). Any future actions to improve drinking water quality in the area will have to consider the impacts that flooding or landslides would have on the water quality. 5.3 Conclusions The residents of the Hatzic Valley are lucky; their groundwater has not been highly impacted by human activity (land use) like some of the other aquifers in the Lower Fraser Valley. There are, however, localized areas that should be monitored to ensure they do not deteriorate further. Hatzic Island is the main area of concern. The density of septic systems and proximity of wells to septic systems in the subdivisions on the island are a cause for concern. Elevated nitrate levels were found in these areas and further monitoring is recommended to determine how widespread these problems are. Considering the high seasonal increase in population on Hatzic Island during the summer, steps should be taken to 92 consider a new source of drinking water for this area especially for those living in the subdivisions. All incidences of elevated nitrate are confined to wells less than 12 m deep; therefore these wells should be monitored closely at locations throughout the valley. This project has provided the first set of water quality information that spans all three aquifers located in the Hatzic Watershed. It provides valuable base-line data that can help both residents and the regional district to better understand processes in the watershed that might negatively affect groundwater quality. Establishing this sort of information is particularly important for developing appropriate public policy with regards to future land use planning in the Hatzic Watershed. 93 References QuikChem Method No. 12-107-04-1-B Nitrate + Nitrite. Milwaukee, Lachet Instruments. Final Report: Panel Review of British Columbia's Drinking Water Protection Act (2002). Government of British Columbia. Drinking Water Protection Regulation (2003). B.C. Reg 200/2003. O.C. 508/2003. Water (2003). Government of Ontario: Queen's Printer for Ontario Accessed: November 20. Updated: November 13, 2003: www.ene.gov.on.ca/water.htm Allen, M., J . Clancy and E. Rice (2000). "The Plain, Hard Truth about Pathogen Monitoring." Journal of the American Waterworks Association 92 (9): 63-76 Armstrong, J .E . (1980). Surticial Geology Mission, British Columbia; NTS Map Sheet 92/1;, Geological Survey of Canada. Auditor General of British Columbia (1999). Protecting Drinking-Water Sources: 1998/1999: Report 5: Office of the Auditor General of British Columbia. Victoria, British Columbia: Office of the Auditor General. A W W A Organisms in Water Committee (1987). "Committee Report: Microbiological Considerations for Drinking Water Regulation Revisions." Journal of the American Waterworks Association 79 (5): 81-84 Baker, D. (1990). "Groundwater quality assessment through cooperative private well testing: An Ohio example." Journal of Soil and Water Conservation 45: 230-235 Benidickson, J . (2002). "Water Supply and Sewage Infrastructure in Ontario, 1880-1990s: Legal and Institutional Aspects of Public Health and Environmental History." Walkerton Inquiry Commissioned Paper 1 Berka, C , H. Schreier and K. Hall (2001). "Linking Water Quality with Agricultural Intensification in a Rural Watershed." Water, Air and Soil Pollution 127: 389-401 Borchardt, M., P. Bertz, S. Spencer and D. Battigelli (2003). "Incidence of Enteric Viruses in Groundwater from Household Wells in Wisconsin." Applied and Environmental Microbiology 69 (2): 1172-1180 Brandling-Bennett, A .D. (1998). The Water Challenge, in: Providing Safe Drinking Water in Small Systems; Technology, Operations and Economics.(ed.) J Cortruvo, G Craun and N Hearne. Washington, D.C., Lewis Publishers. Burkart, M.R. and J.D. Stoner (2002). "Nitrate in aquifers beneath agricultural systems." Water Science & Technology 45 (9) Cameron, K. (1998). Kenworthy Creek Community Watershed: Coastal Watershed Assessment Level 1. Mission, BC , (Forest Technician, District of Mission). Carmichael, V., M. Wei and L. Ringham (1995). Fraser Valley Groundwater Monitoring Program: Final Report, Ministry of Environment Lands and Parks and Agriculture, Fish and Food. Cey, E., D. Rudolph, G. Parkin and R. Aravena (1998). "Quantifying groundwater discharge to a small perennial stream in southern Ontario, Canada." Journal of Hydrology 210: 21-37 Christensen, R. and B. Parfitt (2003). Watered Down: A Report on Waterborne Disease in British Columbia, Sierra Legal Defence Fund. 94 Coote, D.R. and L.J.G. (eds.) (2000). The health of our water: toward sustainable agriculture in Canada. Publication; 2020/E. Ottawa, Research Branch Agriculture and Agri-Food Canada. Craun, G. , P. Bergerand R. Calderon (1997). "Coliform Bacteria and Waterborne Disease Outbreaks." Journal of the American Waterworks Association 89 (3): 96-105 Craun, G. and R. Calderon (2001). "Waterborne Disease Outbreaks Caused by Distribution System Deficiencies." Journal of the American Waterworks Association 93 (9): 64-75 Dakin, A. (1994). Groundwater Resources of the Basins, Lowlands and Plains, in: Groundwater Resources of British Columbia.(ed.) AW Atwater, B.C Environment and Environment Canada. DeLoe, R.C., S .E . DiGiantomasso and R.D. Kreutzwiser (2002). "Local Capacity for Groundwater Protection in Ontario." Environmental Management 29 (2): 217-233 deVilliers, M. (1999). Water. Toronto, Stoddart Publishing. Diamond, D. (1995). QuikChem Method 10-115-01-1-A Orthophosphate in Waters. Milwaukee, Lachat Instruments. Drinnan, W. (1975). A Brief Review of the Water Quality of Hatzic Lake with Respect to Future Land-Use Planning. Victoria, BC , Province of British Columbia: Environmental Water Investigation Branch. Environment Canada (2003a). Quickfacts Environment Canada Accessed: Sept 10. Updated: 2003-04-03: http://www.ec.gc.ca/water/en/e_quickfacts.htm Environment Canada (2003b). Almost nine million Canadians depend on groundwater Environment Canada Accessed: September 10. Updated: 2001-03-29: www.ec.gc.ca/water/en/nature/grdwtr/e_sixmil.htm Eyre, B.D. and P. Pepperell (1999). "A spatially intensive approach to water quality monitoring in the Rous River catchment, NSW, Australia." Journal of Environmental Management 56 (2): 97-118 Federal-Provincial Subcommittee on Drinking Water (2003). Summary of Guidelines for Canadian Drinking Water Quality Accessed: February 3rd, 2004. Updated: http://www.hc-sc.gc.ca/hecs-sesc/water/pdf/summary.pdf Follet, R.F., (ed). (1989). Nitrogen Management and Ground Water Protection. The Netherlands, Elsevier. Gilliam, J.W., D.L. Osmond and R.O. Evans (1997). Selected Agricultural Best Management Practices to Control Nitrogen in the Neuse River Basin: North Carolina Agricultural Research Service Technical Bulletin 311 North Carolina State University Accessed: Updated: http://www.soil.ncsu.edu/lockers/Gilliam_J/BMPs/ Goss, M.J., D.A.J. Barry and D.L. Rudolph (1998). "Contamination in Ontario Farmstead Domestic Wells and its Association with Agriculture: 1. Results from drinking water wells." Journal of Contaminant Hydrology 32: 267-293 Haas, C. (1999). "Benefits of Using a Disinfectant Residual." Journal of the American Waterworks Association 91 (1): 65-69 Halstead, E.C. (1986). Ground water supply - Fraser Lowland, British Columbia, NHRI Paper NO. 26. Harman, J . , J .E . McLellan, D.L. Rudolph, D.J. Heagle, C. Pi l lerand S .E . Denhoed (2000). A Proposed Framework for Managing the Impact of Agriculture on Groundwater: A report prepared for the Sierra-ALERT Coalition for Submission to Part 2 of the Walkerton Inquiry, Sierra- A L E R T . 95 Health Canada - Health Protection Branch (1978-1995). Foodborne and Waterborne Disease in Canada.--. Food-borne and water-borne disease in Canada 1974-1979. Ottawa, Health Protection Branch, Health and Welfare Canada. Hillel, S. (1998). Stabilized Formulation of Hydrogen Peroxide with Silver: a Secondary Disinfectant, in: Providing Safe Drinking Water in Small Systems: Technology, Operations and Economics.(ed.) J Cortruvo, G Craun and N Hearne. Washington, D.C., Lewis Publishers. Hinton, M., S. Schiff and M. English (1993). "Physical properties governing groundwater flow in a glacial till catchment." Journal of Hydrology 142: 229-249 Hogan, M. (2001). Literature Review: Hatzic Prairie Watershed. Prepared for F V R D by Mike Hogan; U C F V Practicum Student. Hudak, P. (1999). "Chloride and Nitrate Distributions in the Hickory Aquifer, Central Texas, USA." Environmental International 25 (4): 393-401 Jaffe, M. and F. DiNovo (1987). Local Groundwater Protection. Washington, American Planning Association. Jaques, D. and H. Rohde (2001). Rural Municipality of Mount Hope # 279: Water Well Inventory and Microbiological Activity Assessment. Regina, Saskatchewan, Prairie Farm Rehabilitation Administrator: Earth Sciences Unit. Kirmeyer, G .J . , M. Friedman, K. Martel, P. Noran and D. Smith (2001). "Practical Guidelines for Maintaining Distribution System Water Quality." Journal of the American Waterworks Association 93 (7): 62 Kraus, N., T. Malfors and P. Slovic (1992). "Intuitive Toxicology: Expert and Lay Judgements of Chemical Risks." Risk Analysis 12 (2): 215-232 Kreye, R. and M. Wei (1994). A Proposed Aquifer Classification System for Groundwater Management in British Columbia, Province of British Columbia, Ministry of Environment Lands and Parks, Water Management Division, Groundwater Section, Hydrology Branch. Lee, D. and J . Cherry (1978). "A Field Exercise on Groundwater Flow Using Seepage Meters and Mini-piezometers." Journal of Geological Education 27: 6-10 Legault, T. (2000). Microbiological Activity and the Deterioration of Water Well Environments on the Canadian Prairies Prairie Farm Rehabilitation Administration, Earth Sciences Unit. Accessed: August 20, 2003. Updated: www.agr.gc.ca/pfra/water/swwi/ian2000t.pdf Leitch, R. (2000). "Balancing Act: Small Community Water Supplier Mulls Affordable Corrosion Control with Pleasing Aesthetics." Water Engineering and Management 147 (9) Lichtenberg, E. and T. M.Penn (2003). "Prevention versus Treatment Under Precautionary Regulation: A Case Study of Groundwater Contamination Under Uncertainty." American Journal of Agricultural Economics 85 (1): 44-58 Liebscher, H., B. Hii and D. McNaughton (1992). Nitrates and Pesticides in the Abbotsford Aquifer: Southwestern British Columbia, Environment Canada. Lippy, E. and S. Waltrip (1984). "Waterborne Disease Outbreaks - 1946-1980: A Thirty-Five-Year Perspective." Journal of the American Waterworks Association: 60-67 Luttmerding, H.A. (1980a). So/'/s of the Langley-Vancouver Map Area: report No. 15 British Columbia Soil Survey: Volume 1 Soil Map Mosaics and Legend, Lower Fraser Valley (Scale 1:25 000). Kelowna, Province of British Columbia, Ministry of Environment, Assessment and Planning Division. 96 Luttmerding, H.A. (1980b). Soils of the Langley-Vancouver Map Area: report No. 15 British Columbia Soil Survey: Volume 2 Soil Maps and Legend, Southern Sunshine Coast and Southern Coast Mountains (Scale 1:50 000). Kelowna, Province of British Columbia, Ministry of Environment, Assessment and Planning Division. McGarrigle, M., J . Bowman, K. Clabby, J . Lucey, P. Cunningham, M. MacCarthaigh, M. Keegan, B. Cantrell, M. Lehane, C. Clenaghan and P. Toner (2002). Chapter 5: The Water Quality of Groundwaters, in: Water Quality in Ireland (1998-2000), Environmental Protection Agency (of Ireland). Meranger, J .C . , K.S. Subramanian and C. Chalifoux (1979). "A National Survey for Cadmium, Chromium, Copper, Lead, Zinc, Calcium, and Magnesium in Canadian Drinking Water Supplies." Environmental Science and Technology 13 (6): 707-711 Muhammetoglu, H., A. MuhammetogJu and S. Soyupak (2002). "Vulnerability of Groundwater to Pollution from Agricultural Diffuse Sources: a case study." Water Science and Technology 45 (9) Murphy, E. (1992). "Nitrate in drinking water wells in Burlington and Mercer Counties, New Jersey." Journal of Soil and Water Conservation 47 (2): 183-187 Nolan, B.T. and J.D. Stoner (2000). "Nutrients in Groundwaters of the Conterminous United States, 1992-1995." Environmental Science and Technology 34 (7): 1156-1165 O'Connor, D. (2002a). Report of the Walkerton Inquiry, Pan: 1: The Events of May 2000 and Related Issues. Toronto, Ministry of the Attorney General of Ontario; Queen's Printer. O'Connor, D. (2002b). Report of the Walkerton Inquiry, Part 2: A Strategy for Safe Drinking Water. Toronto, Ministry of the Attorney General of Ontario; Queen's Printer for Ontario. Oxtobee, J . and K. Novakowski (2002). "A Field Investigation of Groundwater/Surface Water Interaction in a Fractured Bedrock Environment." Journal of Hydrology 269: 169-193 Pacific Hydrology Consultants Ltd. (2003). Hydrogeological Impact Evaluation Concerning the Relocation of the Quarry at 13361 Stave Lake Road In Mission, B.C. - an update of PHCL report of June 21, 1994. Piteau Associates (1994). Review Comments Relating to Groundwater Supplies and Hydrogeological Impacts: Prepared for John Conroy and Residents of Upper Hatzic/McConnel Creek Area: Mission British Columbia. Postel, S. , G .C . Daily and P.R. Erlich (1996). "Human Appropriation of Renewable Fresh Water." Science 271: 785-787 Prokopy, W. (1992). QuikChem Method 10-107-06-2-A. Ammonia in surface water, drinking water and wastewater. Milwaukee, Lachat Instruments. Provincial Health Officer. British Columbia. (2001). A report on the health of British Columbians; Provincial Health Officer's Annual Report 2000: Drinking Water Quality in British Columbia: the Public Health Perspective. Victoria, B.C., Ministry of Health Planning. Reid, D., A. Edwards, D. Cooper, E. Wilson and B. Megrew (2002). "The Quality of Drinking Water from Private Water Supplies in Aberdeenshire, UK." Water Research 37: 245-254 Reynolds, K. (2003). "Coliform Bacteria: A Failed Indicator of Water Quality?" Water Conditioning and Purification Magazine 45 (9). online access (January 6, 2004) at hrtp://www.wcp.net/column.cfm?T=T&ID=2349 97 Rudolph, D.L., D.A.J. Barry and M.J. Goss (1998). "Contamination in Ontario farmstead domestic wells and its association with agriculture: 2. Results from multilevel monitoring well installations." Journal of Contaminant Hydrology 32 (3-4): 295-311 Rutter, M., G . Nichols, A. Swan and J . DeLouvois (2000). "A Survey of the Microbiological Quality of Private Water Supplies in England." Epidemiology and Infection 124: 417-425 Scherer, C. (1990). "Communicating Water Quality Risk." Journal of Soil and Water Conservation 45 (2): 189-200 Schreiber, J.D., R.A. Rebich and C M . Cooper (2001). "Dynamics of Diffuse Pollution for US Southern Watersheds." Water Research 35 (10): 2534-2542 Schreier, H., K. Hall, L. Elliott, J . Addah and K. Li (2003). Groundwater and Surface Water Issues in Agassiz, BC, By: Institute for Resources, Environment and Sustainability for the District of Kent & Agassiz, B C : Multimedia Report. Schreier, H., P. Scales, K. Hall, B. Wernick, W. Tamagi, A. Kenney, W. Thompson, S. Brown and L.M. Lavkulich (1996). A Groundwater Quality Assessment in the Hopington Aquifer, The Corporation of the Township of Langley (Engineering Division) and Fraser River Action Plan: Environment Canada and Department of Fisheries and Oceans. Siegel, S. (1956). Nonparametric Statistics for the Behavioral Sciences. New York, McGraw-Hill Book Company. StatSoft (2002). Electronic Statistics Textbook StatSoft Accessed: Jul y 11th. Updated: http://www.statsoft.com/textbook/stathome.html Summers, R. and J . FitzGibbon (2003). Groundwater Protection Through Water Well Regulation, A Review of Provincial Regulations Across Canada. Canadian Water Resources Association 56th Annual Conference: Water Stewardship: How Are W e Managing?, Vancouver, British Columbia. Tuthill, A., D.B. Meikle and M. Alavanja (1998). "Coliform Bacteria and Nitrate Contamination of Wells in Major Soils in Frederick, Maryland." Journal of Environmental Health 60 (8) VanDerKooij, D., J .H.M. VanLieverloo, J . Schellart and P. Hiemstra (1999). "Maintaining Quality Without A Disinfectant Residual." Journal of the American Waterworks Association 91 (1): 55-64 Wernick, B.G., K.E. Cook and H. Schreier (1998). "Land Use and Streamwater Nitrate-N Dynamics in an Urban-Rural Fringe Watershed." Journal of the American Water Resources Association 34 (3): 639-650 Wetzel, R. (2001). Limnology; Lake and River Ecosystems (3rd Ed.), Academic Press. Wong, B. (2004) Procedure for testing watershed/surface water Unpublished, British Columbia Centre for Disease Control. Vancouver, B.C. Yanggen, D. and S. Born (1990). "Protecting groundwater quality by managing local land use." Journal of Soil and Water Conservation 45 (2): 207-210 Zar, J . (1984). Biostatistical Analysis (2nd Ed.). Englewood Cliffs, N.J., Prentice-Hall. Zebarth, B., B. Hii, H. Liebscher, K. Chipperfield, J . Paul, G. Grove and S. Szeto (1998). "Agricultural Land Use Practices and Nitrate Contamination in the Abbotsford Aquifer, British Columbia, Canada." Agriculture, Ecosystems and Environment 69: 99-112 98 Appendix 2 - News Release NEWS RELEASE FOR IMMEDIATE RELEASE 0 4 J U L Y 2 0 0 2 Participants Required for U B C - F V R D Groundwater Study B C is rapidly waking up to the fact that water is a precious resource that must be protected. One of the leaders in innovative water research, the Institute for Resources and Environment at UBC, is sponsoring a groundwater study in the Hatzic watershed, in collaboration with the Fraser Valley Regional District. The study goals are to determine the quality of the groundwater, and the linkages between land use, groundwater and stream-water. The plan is to select some 100 wells within the Hatzic watershed for water quality analysis. Testing will commence in late July. Participation in the study is on a voluntary and confidential basis. All participants who are selected will receive free testing of their water in the UBC labs, and will receive a final report. The project will examine the chemical composition of the water, identify potential sources of contamination, study the direction of groundwater movement and propose options to maintain or improve the water quality conditions. The project will be carried out with the help of volunteers and students. As the aim of the study is to sample wells that represent different areas, depths, age and capacity of the wells, it is recommended that you sign up early to ensure your well gets tested. To participate contact Bill Walsh of North Fraser Community Futures at 604-826-6252, ext. 120. Leave your name, contact number, mailing address, well depth and approximate age of your well. For more information on the study itself, contact Simone Magwood at magwood@interchange.ubc.ca. 100 Appendix 3 - Instruction Letter Hatzic Watershed Groundwater Survey July 24, 2002 Thank you for participating in the groundwater survey. The sampling of your well is scheduled for Monday, July 29, 2002. On Monday morning July 29, 2002 between 7 and 9 am we would like you to let your tap run for 5 minutes and then fill the bottle. Put your name and address on the bottle and a volunteer will pick up the bottle between 9 and 11 a.m. If you are not at home during that time period please leave the bottle on your front step (or inform us of an alternate location). Make sure the water stays cool (do not put it into the sun). Enclosed with the bottle is a questionnaire, which we would like you to fill out and attach to the bottle or mail to the U B C address below. You will be informed by mail of the result of the analysis in August. We will examine the nitrate, ammonia, phosphate, and salt content in the first set of samples and will do a follow up survey on selective wells for microbial contamination. We plan to conduct a second survey in February and hope you are willing to continue to collaborate with us at that time. If you have any questions do not hesitate to contact us. We would like to thank you for your collaboration. Simone Magwood MSc. Candidate Institute for Resources and Environment University of British Columbia Vancouver, B.C. V6T 1Z3 Tel: 604-822-9245 Email: magwood@interchange.ubc.ca Bill Walsh Watershed Stewardship Coordinator North Fraser Valley Area Community Futures Development Corporation 32286 Fletcher Ave. Mission, B.C. V2V 5T1 (604) 826-622 ex 210 101 Appendix 4 - Report Back Letter «Owner» «Number» «Owner_Address» «City» «Postal_Code» April 13, 2004 R e s u l t s o f the J u l y 2002 W e l l W a t e r S u r v e y Dear Participant Thank you for participating in the well water survey. We appreciate your time and effort. The following results were obtained for the recent well water analysis: «Ni t rate_ppm_N» mg/L of Nitrate-N «Conduct iv i ty_micro_MHO»umhos/cm Conduct iv i ty (salt content) Nitrate-N: Values greater than 10 mg/L are considered a health concern. 10 mg/L is the National Health Standard. Water with Nitrate-N levels between 7 and 9.9 mg/L is of concern and is likely impacted by different land use activities (fertilizers, manure, or septic system effluent). Levels below 3 mg/L are of little concern and considered unpolluted water. Conductivity: Water with less than 100 umhos/cm is considered to be "soft" water with low salt content. Water with greater than 500 umhos/cm is considered to be "hard" water with relatively high salt content. These measurements are not a health concern but they give us an idea about the source of water, the geological formation and the land use influence. Additional tests will be done on selective metals but the data will not be available until the February survey is completed. We hope to do a follow-up analysis in February when the groundwater table is low, and we hope you will once again participate. We will contact you closer to the time. Sincerely yours, Simone Magwood Bill Walsh IPvE-UBC Stewardship Coordinator 604.822.9245 Community Futures Development Corporation of North Fraser 604.826.6252 102 Appendix 5 Survey Institute for Resources and Environment The University of British Columbia Vancouver, B.C. G R O U N D W A T E R SURVEY UBC and the Fraser Valley Regional District are collaborating on a comprehensive groundwater study and we would appreciate your collaboration in filling in this questionnaire. The completion of this questionnaire is voluntary and your response will remain confidential, but your input would significantly improve our understanding of water quality in the area. Please answer by placing an X in the appropriate box or by filling in the space. 1. How many years have you been using your well? la. How many people does your well serve? Years People 2. How deep is your well? f Feet Metres 3. Do you drink your well-water? YES I I NO SOMETIMES 4. Do you filter your well-water? YES I I NO If YES, what kind of filter do you use?_ 5. Do you treat your water in any other way? YES I I I NO If YES, how do you treat your water?_ 6. Do you drink bottled water at home? ALWAYS I I I OFTEN I 1 I SOMETIMES I I NEVER 7. Does your well provide sufficient water throughout the year? YES I I I NO \ 8. Are you engaged in: (Please place an X in the boxes that best represent the amount of activity) Occupation Full-time Part-time Never Farming / Agriculture Other professional service EXCELLENT GOOD MODERATE FAIR POOR 10. Do you think an increase in groundwater aquifer use is appropriate? YES LIMITED USE ONLY NEED MORE INFO NO 103 11. H o w i m p o r t a n t i s e a c h o f t he f o l l o w i n g activities i n c a u s i n g w a t e r q u a l i t y p r o b l e m s ? ( P l e a s e c i r c l e the n u m b e r that best r e p r e s e n t s the i m p o r t a n c e o f e a c h a c t i v i t y ) S T R A T E G Y E x t r e m e l y i m p o r t a n t M o d e r a t e l y i m p o r t a n t N o t at a l l i m p o r t a n t 1 1 a F a r m i n g ( f e r t i l i z e r use ) 5 4 3 2 1 0 l i b F a r m i n g ( m a n u r e use ) 5 4 3 2 1 0 11c F a r m i n g ( c h e m i c a l s ) 5 4 3 2 1 0 l i d H o b b y f a r m s 5 4 3 2 1 0 l i e L a w n f e r t i l i z a t i o n 5 4 3 2 1 0 1 I f G o l f c o u r s e m a n a g e m e n t 5 4 3 2 1 0 H g S e p t i c s y s t e m s 5 4 3 ' 2 1 0 l l h I n d u s t r i a l a c t i v i t y 5 4 3 2 1 0 in A g g r e g a t e E x t r a c t i o n 5 4 3 2 1 0 11.1 O t h e r 5 4 3 2 1 0 12. T o w h a t ex ten t d o y o u t h i n k use o f the R i v e r f l o w S i g n i f i c a n t i m p a c t W a t e r q u a l i t y S i g n i f i c a n t i m p a c t g r o u n d w a t e r a q u i f e r a f f e c t s the local rivers? S o m e i m p a c t S o m e i m p a c t N o i m p a c t N o i m p a c t 13. W h a t t y p e o f management a p p r o a c h d o y o u f a v o u r ? V o l u n t a r y | | | R e g u l a t i o n A C o m b i n a t i o n 14. H o w a p p r o p r i a t e d o y o u t h i n k the f o l l o w i n g strategies a re f o r m a n a g i n g g r o u n d w a t e r r e s o u r c e s ? S T R A T E G Y E x t r e m e l y a p p r o p r i a t e M o d e r a t e N o t a p p r o p r i a t e 14a R e s t r i c t i o n o n f e r t i l i z e r use i n a g r i c u l t u r e 5 4 3 2 1 0 1 4 b R e s t r i c t i o n s o n m a n u r e a p p l i c a t i o n s 5 4 3 2 1 0 14c R e s t r i c t l a w n & g a r d e n u s e o f c h e m i c a l s 5 4 3 2 1 0 1 4 d I n t r o d u c e s e p t i c s y s t e m m o n i t o r i n g & s e r v i c i n g r e g u l a t i o n s 5 4 3 2 1 0 14e C o n t r o l r o a d r u n o f f 5 4 3 2 1 0 1 4 f I n t r o d u c t i o n o f a m u n i c i p a l s e w e r s y s t e m 5 4 3 2 1 0 1 4 g R e g u l a t e l a n d use 5 4 3 2 1 0 1 4 h R e s t r i c t i n d u s t r i a l d e v e l o p m e n t 5 4 3 2 1 0 1 4 i R e s t r i c t u r b a n d e v e l o p m e n t 5 4 3 2 1 0 O t h e r 5 4 3 2 1 0 15. W h a t t y p e o f land use a c t i v i t y o c c u r s w i t h i n 100 m o f y o u r w e l l ? 16. H a v e y o u h a d a n y problems w i t h y o u r w e l l ? 17. H o w o f t e n d o y o u test y o u r w e l l ? ( P l e a s e C h e c k the A p p r o p r i a t e B o x ) O n c e a Y e a r E v e r y 2 Y e a r s E v e r y 3 Y e a r s O t h e r B a c t e r i a C h e m i c a l 18. H a v e y o u h a d a n y c h e m i c a l a n d b a c t e r i a l exceedances i n y o u r w e l l w a t e r . I f Y E S , e x p l a i n 1 I I I I I 19. D o y o u h a v e a s e p t i c s y s t e m ? I f Y E S , H o w c l o s e i f y o u r s e p t i c s y s t e m to y o u r w e l l ( i n m e t r e s ) 20. W h e n w a s y o u r septic system i n s t a l l e d ? 104 21. H o w o f t e n d o y o u service y o u r s y s t e m ? ( P l e a s e c i r c l e the c o r r e c t r e s p o n s e ) O n c e / Y e a r O n c e / 2 y e a r s O n c e / 3 Y e a r s O n c e / 5 Y e a r s O n c e / 1 0 y e a r s N e v e r 22. H o w likely i s i t that y o u o r s o m e o n e i n y o u r f a m i l y w i l l s u f f e r t he e f f ec t s o f : H i g h l y l i k e l y L i k e l y V e r y U n l i k e l y 2 2 a N a t u r a l D i s a s t e r s s u c h as flooding o r e a r t h q u a k e s 5 4 3 2 1 0 2 2 b A i r Q u a l i t y i n t he R e g i o n 5 4 3 2 1 0 2 2 c P e s t i c i d e R e s i d u e i n l o c a l a i r , w a t e r o r s o i l 5 4 3 2 1 0 2 2 d D o w n s t r e a m E f f e c t s o f I n d u s t r i a l P o l l u t i o n 5 4 3 2 1 0 2 2 e F e c a l C o l i f o r m i n D r i n k i n g W a t e r 5 4 3 2 1 0 . H o w m u c h control d o y o u see y o u r s e l f as h a v i n g o v e r a n y r i s k s p o s e d b y the f o l l o w i n g : N o C o n t r o l S o m e C o n t r o l M u c h C o n t r o l 2 3 a N a t u r a l D i s a s t e r s s u c h as flooding o r e a r t h q u a k e s 5 4 3 2 1 0 2 3 b A i r Q u a l i t y i n t he R e g i o n 5 4 3 2 1 0 2 3 c P e s t i c i d e R e s i d u e i n l o c a l a i r , w a t e r o r s o i l 5 4 3 2 1 0 2 3 d D o w n s t r e a m E f f e c t s o f I n d u s t r i a l P o l l u t i o n 5 4 3 2 1 0 2 3 e F e c a l C o l i f o r m i n D r i n k i n g W a t e r 5 4 3 2 1 0 24. H o w i m p o r t a n t are the f o l l o w i n g as a g u i d e f o r i n d i c a t i n g the q u a l i t y o f y o u r w a t e r ? : Not at all Important Very Important 2 4 a S m e l l / T a s t e 7 6 5 4 3 2 1 2 4 b C l o u d i n e s s 7 6 5 4 3 2 1 2 4 c C o l o u r 7 6 5 4 3 2 1 2 4 d V i s i b l e A b n o r m a l i t i e s ( e . g . , c h a n g e i n c o l o u r ) 7 6 5 4 3 2 1 2 4 e D e p t h o f W a t e r T a b l e 7 6 5 4 3 2 1 2 4 f A m o u n t o f v i s i b l e p a r t i c u l a t e ma t t e r i n a g l a s s o f w a t e r 7 6 5 4 3 2 1 2 4 g L o c a l N e w s p a p e r r e p o r t s o n the q u a l i t y o f n e a r b y b o d i e s o f w a t e r 7 6 5 4 3 2 1 2 4 h M u l t i p l e i n c i d e n t s o f g a s t r o i n t e s t i n a l i l l n e s s i n t he c o m m u n i t y 7 6 5 4 3 2 1. Circle the answer that you feel is most correct: 25. I f y o u are e x p o s e d to e v e n the s m a l l e s t a m o u n t o f a w a t e r - b o r n e p a t h o g e n s u c h as E-coli o r Giardia, y o u are l i k e l y to s u f f e r a d v e r s e h e a l t h e f f e c t s . S t r o n g l y A g r e e | A g r e e | D i s a g r e e | S t r o n g l y D i s a g r e e 26. Y o u r h e a l t h w i l l n o t b e n e g a t i v e l y a f f e c t e d b y pesticides u n l e s s y o u are e x p o s e d to a lo t o f the c h e m i c a l o v e r a l o n g p e r i o d o f t i m e . A g r e e D i s a g r e e 27. M o s t w a t e r q u a l i t y r i s k s c a n b e e l i m i n a t e d b y a c o m m o n h o u s e h o l d filter. A g r e e D i s a g r e e 28. P e o p l e a re u n n e c e s s a r i l y f r i g h t e n e d a b o u t v e r y s m a l l a m o u n t s o f c o n t a m i n a n t s f o u n d i n g r o u n d w a t e r A g r e e D i s a g r e e 105 29. O n the w h o l e , the r i s k s to h u m a n h e a l t h p o s e d b y w a t e r q u a l i t y p r o b l e m s a re fa r g r e a t e r t h a n the r i s k s p o s e d to the l o c a l fish, f l o r a a n d f a u n a . A g r e e | D i s a g r e e | 30.. I n o r d e r to a r r i v e at a s u s t a i n a b l e u s e o f the g r o u n d w a t e r r e s o u r c e s ... A . W h a t d o y o u t h i n k y o u c o u l d d o as a n i n d i v i d u a l ? B . W h a t s h o u l d the m u n i c i p a l i t y d o to i m p r o v e the s i t u a t i o n ? C . W h a t a c t i o n s a re n e e d e d b y the p r o v i n c i a l a n d f e d e r a l g o v e r n m e n t s ? T h a n k y o u f o r y o u r c o o p e r a t i o n , W e w i l l t a b u l a t e the resu l t s a n d p r o v i d e y o u w i t h a s u m m a r y b e f o r e t he n e x t w a t e r q u a l i t y s u r v e y . S i n c e r e l y , S i m o n e M a g w o o d M S c . C a n d i d a t e Ins t i t u te f o r R e s o u r c e s a n d E n v i r o n m e n t U n i v e r s i t y o f B r i t i s h C o l u m b i a # 4 8 E - 2 2 0 6 E a s t M a l l V a n c o u v e r , B . C . V 6 T 1 Z 3 magwood@interchange.ubc.ca 106 Appendix 6 - Results of Blind Duplicates Sample # Conductivity uS/cm PH ppm P 0 4 ppm NH3-N ppm N0 3 -N Boron Calcium Well 47 109 7.44 0.115 0.025 0.138 0.014389 12.7265 101 7.42 0.403 0.051 0.141 0.013002 12.8138 Well 41 180 8.40 0.445 0.039 0.005 0.076946 15.2703 258 8.26 0.512 0.052 0.005 0.088161 15.0911 Potassium Magnesium Manganese Sodium Silicon Strontium Zinc Well 47 0.846126 2.64969 2.28885 6.96607 0.030732 0.877814 2.66057 2.03754 6.9664 0.030511 Well 41 1.82421 3.86545 0.030937 9.45733 7.46018 0.043704 0.50827 1.85232 3.84832 0.030718 9.57943 7.4068 0.043773 0.487846 107 Appendix 7. Soil and Surficial Geology Codes Soil Texture Codes Used in the GIS (from Luttmerding, 1980) Texture Drainage 1 Fine 1 Poor to very poor 2 Moderately fine to medium 2 Poor / Imperfect 3 Medium 3 Moderately Well 4 Medium to moderately course 4 Moderately Well to Well 5 Coarse 5 Well to Rapid Parent Material Categories 1 Glaciomarine Deposits 2 Well decomposed organic material over floodplain deposits 3 Medium textured eolian deposits over moderately coarse textured glacial till 4 Laterally accreted floodplain deposits over 5 Laterally accreted floodplain deposits over sand. 6 Local stream deposits 7 Eolian deposits over gravely glacial outwash Surficial Geology Codes Used in GIS (from Armstrong, 1980) 0 Peat 1 Sandy loam and clay loam 2 Stony silt to Loamy Clay Sandy Till 3 Sandy Loam and Loamy Sand 4 Sand and Rubble Gravel and Rubble 4 Gravel and Sand Gravel, sand and rubble 5 Bedrock 108 Appendix 8 - Groundwater Sampling Data Extra Wells Sampled (Winter Sampling) near Well 19 Well Number Depth (m) Conductivity (LiS/cm) pH Ammonia (mg/L) Nitrate-N (mg/L) Aluminium (mg/L) Boron(mg/L) Barium (mg/L) Calcium (mg/L) 81 Not known 130 6.22 0.059 3.141 0.050 0.0199 0.0100 12.330 82 Not-known 140 6.56 0.050 1.860 0.050 0.0100 0.0100 12.785 83 Not-known 159 6.59 0.060 0.969 0.050 0.0122 0.0146 14.791 Well NumberCopper (mg/L)Iron (mg/L) Potassium (mg/L)Magnesium (mg/L)Manganese (mg/L)Sodium (mg/L)Silicon (mg/L) Strontium (mg/L)Zinc (mg/L) 81 0.0500 0.0500 0.5000 6.4116 0.0050 1.4163 8.9860 0.0589 0.0100 82 0.0500 0.0500 0.5000 6.4188 0.0050 1.9239 11.3192 0.0651 0.0975 83 0.0828 0.0500 0.5000 7.6378 0.0117 3.8325 11.6850 0.0771 0.0100 Well Number %For50 %Rur50 %Ag50 %Urb50 %For100 %Rur100 %Ag100 %Urb100 81 0.0 77.4 7.8 0.0 0.0 42.0 25.2 0.0 82 0.0 70.5 20.6 0.0 0.0 36.3 35.7 0.0 83 0.0 55.7 43.8 0.0 0.0 23.8 71.8 0.0 Well Number %For200 %Rur200 %Ag200 %Urb200 Drainage Code Texture code Geology Code Surficial Texture Parent Material 81 5.1 20.7 31.8 0.0 1 2 1 3 • 4 82 2.7 17.8 43.6 0.0 4 3 1 3 4 83 0.0 8.0 89.4 0.0 1 2 1 3 4 109 Well Aquifer Conductivity (uS/cm) pH Orthophosphate (mg/L] Ammonia (mg/L) Nitrate-N (mg/L) Number Number Depth (m) Winter Summer Winter Summer Summer Winter Summer Winter Summer 1 1 9.4488 .... 219 160 6.16 6 19 0.429 0.05 0 05 3 008 1.003 2 1 • 14 92_ 100 5.90 5.82 _ ° . : 3 8 1 . _0.05 _ 0 05 0.05 0 115 3 24 38 not-tested 240 not-tested 7.01 l l i l i l l i i l 0.466 not-tested 0 321 not-tested 0.05 4 1 6 71 129 •oo 63' 6.33 0.405 0 05 0.05 1.064 0 679 5 I H t l 7.01 129 130 6 44 6.38 j f j l i j j j 0.341 0.05 0 05 3.075 4.828 G 1 6.10 185 180 6 28 6.30 0.397 0.05 0 05 4 933 5.286 7 umiiii 18.29 92 100 6.15 6.18 0.367 0.05 0.05 0 274 0.274 8 1 8.53 93 120 6.48 6 29 f j j j j j l 0.385 0 05 0.05 )56 _ 0.674 9 I B B 0.00 169 170 6 22 6 15 0.458 Slllllilt 0.05 0 05 0 287 0 235 10 1 7.62 154 160 6.13 6.14 0.366 0.05 0.05 . 581 1 983 11 l l i i iH 0.00 275 200 6 11 6.16 0 521 0 05 0 05 11 962 4.538 12 1 7 62 162 180 6.30 6.30 0.542 0.05 0 05 3 369 4 705 14 IlllJili 6 10 67 110 6.66 6 40 0 239 0 053 0 05 0 498 0 357 15 0.00 199 230 6.53 6^,58 0.267 0.05 0.05 2.I68 3 284 16 i l l l l l i 9 14 173 130 6-39 JX'' 6.40 iBliiiiil 0 258 • H H P • B i l l 0 05 0 05 5 307 0 579 17 1 6.10 157 170 6.32 6.49 0.331 0.05 0 05 0 05 0.05 18 i i i i i i i i 5 18 ISSKiHil 150 6.59 6.58 0.298 KlHlll 0.05 0.05 0.647 0.586 19 1 4.27 235 250 6.3 6 28 0.276 0.061 0.05 7.499 10.129 20 IEEI1I 9.14 150 6 40 6.39 j j l j j l l 0.283 0.05 0 05 2 462 2 443 21 1 0.00 168 150 62- 6.28 0.307 l l a i S l 0.05 0.05 0.787 0^ 559 22 9 14 not-tested 160 not-tested 6.17 • j j j j j j 0 300 not-tested 0 05 not-tested 2.517 23 1 9 14 130 130 6.18 6 14 0.270 0 05 0.05 0.422_ 0 240 24 lllfSl 6.10 153 150 6 43 6 36 0 284 0.05 0 05 1 674 1.236 25 1 7 62 _390 410 6 8- 6 95 0.162 0.188 0 05 0.05 0. 26 91.44 3290 3200 7.92 7.92 Hill 0.186 JI1I11 0 05 0.663 0 05 "'• 0.05 27 28 _ 2 ^ 0 00 10 06 77 84 100 130 6 51 6 49 6.46 6 38 0.05 0 053 0.05 0.05 0.05 0 05 0 4-0 513 0 949 1 029 29 2 3.66 70 70 6.34 7.21 0 052 0.05 _0.05 0 812 0 339 30 2 22.86 not-tested 140 not-tested 7 04 0.116 not-tested 0 05 not-tested 0 398 31 2 9-:-" 103 100 6.03 6 18 0.05 0.067 0.05 1.557 0.!-32 BB1III1 5 49 55 50 6.05 6 06 0 052 0 05 0 05 0 372 0.077 33 2 3 66 51 50 6.43 6. 0.055 0.05 0 05 0.586 o.: 34 Bllllll 0.00 llSEilllH 60 6 27 6.20 0 057 IBB 0 05 0 05 1.012 0.324 35 2 12 19 120 90 6.3 6.35 0.05 0.063 0 05 0.587 o.: 36 IIIIIIII 76.20 130 130 7.78 7.66 0.087 0.056 0.05 0.073 0 071 37„. 2 19.51 155 130 7 0! 7.08 0.107 _ ° - 0 5 0.05 1.015 0.425 38 137 16 194 270 9.03 6 63 0 109 tiiiiiiiii:! 0.05 0.05 0.05 0.05 39 2 5.18 68 70 5.80 5.89 0.057 0.05 0.05 1.004 0.794 110 Well Number Aquifer Number Depth (m) Conductivity (nS/cm) Winter Summer PH Winter Summer Orthophosphate (mg/L) Summer Ammonia (mg/L) Winter Summer Nitrate-N (mg/L) Winter Summer 40 2 60 96 610 550 8 40 8.35 0.249 0 099 0.061 0 05 0 05 41 2 79.25 I 8 0 . , 170 8.40 8.10 0.123 0.05 0 05 0.05 0 C 5 42 Bll i i l 60 96 1030 1000 8 21 8 07 0 126 0 076 0.062 0 05 0 05 43 44 3 i B i l B 5 49 56 39 104 59 2lT: 90 6 42 5.88 6 41 0.05 0 053 0.05 0 05 0.05 0 05 3.447 0.283 3.141 • • i i i p H i ^ i n n 0 274 45 3 19.20 ;40 330 7 91 7.85 0.190 0.105 0.085 0.05 0.05 46 • B i l l 52.12 7 21 7 21 T" " " ' 0.069 0 05 0 05 0.284 0 284 47 3 0.00 109 110 7 44 7.44 0.082 0.051 0.05 0.141 0.134 48 l l l f l l l l 0 00 6 67 6.95 J " : . .7 " 0.05 0 05 0 05 0 452 0 368 49 3 7.62 not-tested 110 not-tested 6.60 .070 not-tested _ a o 5 ^ not-tested 0 462 50 lllliiB 41.76 116 " ' IBlSIfillB 8 14 7 92 0.075 0.05 0 05 0 05 0 05 51 3 56.39 106 100 ' 18 7 49 0.078 0 05 _ O J 0 5 360 0.051 52 llllIIH 5.49 BIISIIIII 7.27 7.38 0.05 0 05 0.05 0 2 1 6 0.184 53 3 5.49 161 180 6 66 7.05 0.118 0.05 0.05 2.609 1.863 54 3 30 48 170 160 8 32 8.20 0.124 0.055 0.05 0 05 0.05 55 3 36.58 141 160 8 23 8 22 0.133 0.05 0.05 0.05 0.05 56 3 56.39 201 60 7.32 6 27 0.065 0.053 0.05 0.309 0.581 57 3 67.06 53 50 6 16 6.22 0.05 0.05 0.05 0.567 0 625 58 3 7.62 130 6 35 6.63 0,066 0.05 0.05 4.061 2.784 59 2 13.72 54 60 6.59 6 56 0.05 0.053 0.05 0 391 0.5( 60 3 54.86 illBlilBB IHIii l l l 6 12 6 11 :. '05 0.05 0 05 0.728 ' 61 3 28.96 47 60 6 23 6 5 3 i.05 0.054 9-S5....... o 3 : . 62 l i l l i l l l 0.00 IHIH1SB 6 22 6 41 0 05 0.05 0 05 0 179 0.126 63 3 43. • 57 60 6 03 6 22 C.05 0.05 0 05 0711 0.591 64 BBBil 24 38 5.85 6 07 0 05 0 052 0.05 0.544 0 638 65 3 18 29 34 40 5 99 6.10 0.05 0.059 0.05 0 427 0.303 66 Bllllll 24 38 BllKiifllfl 6.07 6.00 0.05 0.05 0 05 0 243 0 239 67 3 36.58 44 50 6.00 J6.00 _ C 05 0.05 0.05 '14 0.574 68 JHIiill 32 6 27 6.17 0.05 0 083 0 05 0 352 0 570 69 3 30.48 33 40 6 21 6 32 0 05 0.052 0.05 H 8 0 343 70 1IIB1B 12 80 6.07 6 02 0.05 0 086 0 05 0.496 0 369 71 3 128.63 134 150 8.41 8.24 0 063 0.061 0 05 0 05 0 05 73 19 81 6 18 6.31 0.051 0 05 0 05 0 237 0 184 74 3 6 10 44 50 5.73 5 .83_ 0.05 0,05 J 3 J 0 5 _ 0.814 07 75 IIIIIBI 11 58 240 7.81 7 65 0 296 0 826 0 988 0.05 0 05 76 77 3 l i l l i l l l 2 74 0 00 33 3100 50 3100 6 26 8 05 6.49 8.07 0 074 0.292 0.075 0 154 0.059^ 0.124 0.05 0.249 ••• 0 2 36 79 2 0.91 141 100 6.05 6.68 0 0 6 7 0.054 0.05 6.111 0.901 111 Well Aluminium (mg/L) Boron(mg/L) Barium (mg/L) Calcium (mg/L) Copper (mg/L) Iron (mg/L) Potassium (mg/L) Number Winter Winter Summer Winter Winter Summer Winter Summer Winter Summer Winter Summer 1 0 0166 0 1 0 0162 19.093 17.1042 0.05 0.0346 0.05 02 0.5833 0.5558 2 0.05 0 01 0.1 0.01 9.291 11 9723 0.1454 ._0.1i63.„ Jl-95 0.2 0 8393 0.9205 3 not-tested not-tested 0.1 not-tested not-tested 36.3294 not-tested 0.025 not-tested 0 2498 not-tested 1.8484 4 0.0E 0.0287 0.1 0.0136 11.908 11.0115 0.05 0-025_ 0.05 0.2 0.6785 0.6882 5 0.05 0.0110 0.1 0.01 11.706 14.6530 0 05 0.1783 0 05 0.2 0.5 0.2523 6 0.05 0.0454 0.1 0.0144 16.131 16.1514 0.05 0.0460 0.05 0.2 0.5 0.4593 7 0.05 0.01 IllIIIllIII 0.01 10.089 10.8840 0.05 0.025 0.05 0.2 0 6950 0 7292 8 0.05 0.0116 0.1 0.01 10.246 13.5828 0J)8j57__ 0.025 ^  0 05 0.2 0.5 0 8107 9 0.05 0 01 0.1 0.01 16.956 18.1892 1.3882 0.5348 0.05 0.2 0.5 0.2657 10 0.05 0.0352 0.1 0 01 14.902 15.7194 O 0 5 _ _ C£25_ ^_0.05 0.2 0.6754 11 0 05 0 0676 0 1 0 0234 15.603 13.4970 0.05 0.025 0.05 0.2 0.8394 0 6773 12 0 05 0,0399 _ 0.1 0.0146 11.651 14.7344 0.05 0.0664 0 0641 0 0447 02 0 5 _ _ J0.4611 14 0.05 0.01 • 0 1 0 01 5 685 10.3113 0 0542 02 0.5 0 4872 15 0.05 0.0163 0.1 0.0332 23.838 29.9904 0.05 0 025 0 0894 02 5.1350 7 1459 16 0.05 0 01':-, 0 0315 15.614 12 7727 0 0914 0 0833 0 05 0.2 1.7337 1 6744 17 0.05 CU)195 0 1 0.01 0.128 0 5 0 05 0 025 0.05 0.2 0 5 ,0_.1389_ 18 0 05 0.0147 0 01 13 858 ;1 fe .09^ 0 05 0.025 0.0518 02 0 5 0.3784 19 0 05 0.0119 0 1 0 0162 19.106 22.7780 0.05 0.0724 _J3J35._ 0.2 0.5_^ 0.3403^ 20 0 05 0.0116 1BIBII11 0.01 11 686 13 4597 0 1841 0.1698 0.05 02 0 5 0.2917 21 0 05 0 0175_ 0 1 ).01 17.148 17.0423 O0534 0.0376 J2J748 0.5840 0.5 ^0.3010_ 22 not-tested not-tested 0 1 not-tested not-tested 15.9074 not-tested 0 0546 not-tested 0.2 not-tested 0 2568 23 0.05 0.0103 0 1 0.0116 11.957 12.5883 0.05 _ 0.0635 _ 0 05 0.2 0.5 0.2939 24 0.05 0 0171 0.1 0 0131 15.549 15.4982 0 0982 0 1254 0 05 0.2 0.5884 0.6212 25 0.05 0 01 0.1 0 0167 20.370 21.2070 0.05 0.025 0.3204 0.2 0.6150 0.6186 26 0.05 0.4436 0.465058 0.0393 200.195 183.7600 0.1724 0.0565 0 8440 0 4150 16.8919 18 7202 27 0.05 0 0223 0.1 0 01 7.913 11.2363 0.05 0.025 0.05 0.2 0.5 0.5484 28 0.05 0 0173 0 1 0 01 9 395 15 3154 0 05 0.025 0.1104 0.2 0.5223 0.6506 29 0 05 0 0473 0 1 101 8 138 7.8171 0.2475 0.025^ not-tested 0.02£r* 0.0868 0.2 0.5 0.4159 30 not-tested not-tested llolllll not-tested not-tested 7.9970 not-tested 0.2 not-tested 1 4119 31 0 05 0.0672 0 1 I.01 10.083 9.3580 ^  0.0603 0.1195 0.0904 0.2 0.7336 _ 0.7010_ 32 0 05 0 0358 lillilll 0 01 4.992 4 3738 0.1045 0 1429 0 05 02 0 5 0 1953 33 0 05 0.01 0 1 0.01 6 39b 5.9797 0.05 0.025 0.05 0.2 0 5 0 2182 34 0 05 0 0212 MIMlill 0 01 4 724 6 3959 0:1457" 0 1879 0 05 02 0 5 0.1 35 0.05 0.1746 0 1 0.01 6.121 4.8655 0.05 0.025 0.1461 0.2423 0 5030 0.4120 36 0 05 0 1562 lillilll 0 01 17.389 17.3370 0.05 0 025 0 05 02 0.6812 0 7050 37 0.05 0.0200 0.1 J3.01 17.313 15 7640 0.05 0.0779 0.05 0.2 1.1136 1 ;0907_ 38 0.05 3 3658 3 70366 0 01 1 585 1 9144 0 05 0 025 0 05 02 0 8857 0 2569 39 0.05 0.0160 0.1 0.01 6.512 6.2763 0.05 0.025 0.05 0.2 1.8521 1.9902 112 Wel l A l u m i n i u m (mg/L) B o r o n ( m g / L ) B a r i u m (mg/L) C a l c i u m (mg/L) C o p p e r (mg/L) Iron (mg/L) P o t a s s i u m (mg/L) N u m b e r Winter Winter S u m m e r Winter Winter S u m m e r Winter S u m m e r Winter S u m m e r Winter S u m m e r 40 0.05 0.1598 U .138485 0 01 15 245 14.1860 0 05 0.025 0 05 0.2 3.9491 3.9920 41 0.05 0.0769 0 1 0 01 15.270 15.9458 0 05 0 025 0 05 0.2 1 8242 1.9746 42 III 0 05 0 0814 0.1 0 0334 47 475 54.3970 0.05 0.025 0.05 0.2 4 6105 5 0650 43 0 05 0.01 0 1 0.0520 6 f - . ^ 7.5518^ ^ 0 . 0 5 ^ 0 1073 0 05 0 . 2 _ 0 2 0.5 4.5708 44 0.05 0.01 0 1 0 01 5 201 6 3886 0 05 0.2044 0 2932 0.5 0 3199 45 0.05 0.0141 0.1 0.0106 43 811 51.0559 0.05-. 0.025 0.8278 0.5911 2.8193 3.0026 46 0.05 0.0122 0 1 0.01 10 330 11.6396 0.05 0 0322 0.05 0.2 0.6394 0.6626 47 0 05 0 0130 0 1 0.01 12 814 14.7258 _ O L 0 5 _ ° - 0 2 5 _ 0 05 0.2 0.8778 0.9047 48 0 05 0 01 0 1 0.01 1.925 4 1960 0.05 0 025 0.05 0 2 0 5 0 1 49 not-tested not-tested 0.1 not-tested not-tested 14.5965 not-tested 0.1973 not-tested 0.2 not-tested 0.6164 SO 0 05 0 0127 0.1 0 01 14.154 16 1469 0 05 0.025 0.05 0 2 0 9619 1.0117 51 0 05 0.0141 0.1 0.01 11.800 13.3432 0 05 0.025 0 05 0 2 0.9692 1 0393 52 W 0 05 0 01 0 1 0 01 4.206 4.9109 0 05 0 025 0.05 0.2 0 5 0 2929 53 0.05 ° : 0 1 0.1 0 01 19014 24.3708 0.1347 0.7079 0.05 0.2 1 0845 1 6042 54 0.05 0 0216 0.1 0.01 14 082 15.9518 0.05 0 025 0 05 0 2 1.7859 1 8461 55 0 05 0.0164 0.1 0.01 14.008 15.6697 0.05 0.025 0.05 0.2 1.5841 1.7226 56 0.05 0.0679 0.1 0.01 7.660 7.8715 0.05 0.025 0 1089 0 6064 2 1359 0 3399 57 0.05 0.01 0.1 0.01 5.414 6.0102 0.05_ 0.0295 0 05 0 2 0.5 0.2661 58 i l l 0 05 0.01 0.1 0.0142 14 017 21 2033 0.3918 0.2528 0 05 0 2 0.5 0 4579 59 0.05 0 0147 0 1 0 01 »70.„. 7 3684_ 0 0658 0 0512 0 05 0.2 0.5 0.3602 60 0.05 0.01 0.1 0.01 4 638 6 1033 0.05 0.025 0.05 0 2 0 5 0 3480 61 0.05 0 01 0.1 0 01 •' • > 2 J B „ „ . J L 1 4 6 8 0.05 _ 0.025 0.4268 0.4548 0 5 0.3679 I 6 2 0.05651 0 01 0 1 0 01 1.050 1 4244 0.05 0 0400 0 05 0 2 0 5 0 5 63 0.05 0.01 0.1 1 0 01 6.561 6 7867 0.05 jO.0267 0.4773 ° ; 5 3 6 0 . 0 5 0.2395 64 0 05 0 01 0.1 0.01 4.934 5.6863 0.05 0 0615 0 2921 0 2 0 5 0 3514 65 0.05 0.0113 0.1 _ 0.01 3.663 3.7710 0.05 0.025 0.05 2 0 5 0.1948 66 0.05 0.1 0.01 ^48 5 5673 0 0590 0 0571 0.05 0 2 0 5 0 1844 67 0 05 0.01 0 1 0.01 4 5- 5 1587 0.05 0.0366 0.05 0.2 0.5 0 2462 68 0 05 0 01 0.1 0.01 3 926 5 8868 0.05 0 025 0 05 0.2 0 5 0.2237 69 OOO 0 01 0.1 0.01 3.610 3 9162 0 1672 0 1505 0 05 0 2 0.5 0 1769 70 0.05 0 0175 0 1 0.01 3.324 3 3131 0 7072 0 5064 0 0927 0 2 0 5 0 1668 71 0.05 0.5152 0.549991 0.01 12.103 13 7597 0 05 0.025 0 05 0.2 . 0.5274 0.5471 73 111 0.05 0.0101 0.1 0.01 7.144 8.8236 0.05 0.0704 0 1237 0.2 0.5 0.2817 „ „ „ . 7 4 0.05 0.0132 0.01 4.385 5 2274 0.05 ^ 0 . 0 2 5 ^ ^0.4570^ 1.0668 0.5 2.3357 _ 0 . 2 8 8 2 75 0.05 V 6l0499 ' 0 1 0.01 22 330 26 3532 0 05 0 025 1.4696 1.1547 2 4835 76 0.05 0 01 0.01 2.858 6.4499 0 05 0 025 0.05 0.2 0.5 0.1711 77 • 0.05 1 7775 1 97975 0 0145 36 230 40.0727 0 05 0 025 0 05 0 2 12 9222 14 0015 79 0.076069 0.0178 0.1 0.0511 12.649 9.9243 0.05 0.0300 0.05 0.2 7.1830 0.9917 113 Well I Number Magnesium (mg/L) Winter Summer Manganese (mg/L) Winter Summer Sodium Winter (mg/L) Summer Silicon Winter (mg/L) Summer Strontium (mg/L) Winter Summer Zinc Winter (mg/L) Summer 1 2 3 4 5 6 7 _8 9 10 11 12 14 15__ 16 17 18 19 P, 22 23 25 26 27 28 29 31 32 33 34 35 36 37 38 39 10,7010 3J0022 not-tested 4.6554 4 8511 6.6671 3.3624 4.6079 8.6335 6.3147 10 5726 7.4932 3.1341 7.4441 7.8017 0.0910 7 6611 13.8021 6.9795 _8.8362_ not-tested 5.8112 6 0212 18.6850 28 5807 1.3035 1.5141 0.8762 not-tested 1.2514 1 0000 0.8790 0.7870 1.1101 3 0979 5.7891^  0 2098 1.2366 9.5274 ^7805 9 9937 4.2937 5 9489 6.4983 3 6368 5.098J 9 2778 6.5464_ 9 1716 9.3259 5.7854 7.9949 6.7297 0.025 6 5972 15.6578 8.0090 8^ 9418 6 7979 6.0044 5.9087 24.6269 31.3770 1.8777 2 4744 _1.2605_ 1.5523 1.1822 1.0350 0.8175 0 9819 0.8702 3.5436 5.2520 0.3196 1.1954 0.005 _ 0.005 not-tested 0.005 0 005 0 005 0 005 0.005 0.005 0.0134 0 00: _ 0.005 0 005 0 0449 0.0522 0 005 0 0176 0.0051 0 005 0.0264 not-tested 0 0933 0 005 0.2105 0 2655 0.005 0 005 0 005 not-tested 0 0123 0.005 0.005 0.005 0 0365 0.005 0 005_ 0 005 0.005 0J3J? _O05 0.7179 0.05 _ 0 05 0 05 0 05 0.05 0 05 0 05 0.05 0.05 0 05 0 05 0 0545 0.05 _ 0 05 0.05 0.05 O05_ 0 05 0.1127 0 05 0.2613 0 2749 0.05 3 05 0.05 3 05 0.05 0.05 0.05 0.05 0 05 O05 0 05 0.05 3.2136 2.2906 not-tested 5.5479_ 4 2340 9 4758 2 3773 3.3689_ 2 8850 5.4131 _ 23 0823 ,_87j606 1 2475 1.9625 4 1874 36.4937 2 9554 3.5097 2 5901 _2.8297_ not-tested 4.4420 6 2245 27.4218 42^1250 2 6648 2 7968 2 0867 not-tested 5.2623 2.2402 _0.7347_ I. 1806 II. 8864 3.6480 j4.3612_ 43 3531 1.6666 3.5743 3.0866__ 10.0029 6.2771 5 3603 11 6345 3 1194 4.0414 3 7459 6.3213 14.5522 10.1263 19 0647 6.2361 3 9950 I. 6167 2.4524 II. 5021 4.9214 5.4344 56 0303 14.5075 12.0199 not-tested 12.7045 9.6225 12.1082 11 3969 14.3982 12J2801 14 4809 13.2196 10 5351 12.6103 12 1650 11.0038_ 13.4697 10.3088 19 6757 16.9395 8 9493 11 2178 10.3294 -13.0828_ 12.5846 10.3213 11.2936 13.0239 not-tested 10.8850 10.5604 19.2160 11.4689 5.4694 £ 7783 4.7456 not-tested 5.4052 4.5173 6.2175 _ 4.8868 5.5238 7 4330 10.4274 11.9996^ 13.9891 11.3983 17.3494 16.8722^  10.4187 11.3980 11.0145 13.6272 13.0347 11.0675 11.8662 13.9295 12 4058 11.5183 11.2428 19.1252 2.4756 11 2124 6.2636 13 1705 6.3378 6 6933 5.7635 72114 5 6134 6 3421 6.5074 6 2654 5.3241 8.4885 11.1911 12 6575 6.2501 0.0887 0.0542 not-tested 0.0723_ 0.0662 0.094 0 0469 0.0534 0 0777 0.081 0 0723 0 0518 _ 0 0204 0.1090 0.0966 ^ 0.0020_ 0.0603 0.1018 0 0600 0.0843 not-tested 0 0697 0.0968 0 0659^  0 8019 0.0211 0 0271 0.0202 0.081033 0.07386 0.133993 0.072058 0.089826 0.101241 , 0.055687 0.077149 0 087911 0.090212 0 064566 0.069122^ 0.044713 0 14253 0.084221 _ 0.025 _ 0.075895 0120852 0.07534 0.089032 0.094541 0.079431 0103425 0 076082 0 849843 0.036334 0 05216 0.026602 not-tested 0.0273 0 0249 0.0071 0 033408 0 029076 0.028353 0.025 . 0 0148 0.0181 0.0226 0.0497 0 0040 0.0933 , 0.022959 0.025 0.027923 0.049549 0 025. 0.101195 00101 0.0215 not-tested 0 0141 0.0872 0.01_ 0 0194 J0.01_ 0 0158 0.01 0 0330 0.0150 0.2196 0 0346 0 01 0.01 0.4905 0.2156 0.01 0.0134 not-tested 0.0143 0 0264 0.4444 0 0495 0.01 0 0204 0.1097 not-tested 0.0196 0 0336 . ._9:.°J. 0.01 1.9534__ 0 01 0.01 0 01 0.01 02 ; , 0.2 0-2 0 2 0.2 0.2_ 02 02___ 02 0.2 0 2 0.2_ 0.2 0.2 0.2 0.2 "0.338275 02 0.2 02 0.2 02 0 398781 02 0.2 02 02 02 0.2 0.2 0.2 0.2 1.11205 02 02 0.2 114 Well Magnesium (mg/L) Manganese (mg/L) Sodium (mg/L) Silicon (mg/L) Strontium (mg/L) Zinc (mg/L) Number Winter Summer Winter Summer Winter Summer Winter Summer Winter Summer Winter Summer 40 ,9,5657 8 9196 0 0341 0 05 87.7515 99 5555 7.5473 . 8 0344 0 0E85 0 086167 0 01 0.2 41 3 8655 4 0369 0 0309 0 05 9 4573 11 6736 7.4602 81492 ^ 0 04 - 0.05571 0 5083 0.2 42 14.0783 16.7296 0.0864 0.0981 121.0770 137.6110 7.1866 8 0998 0 2020 0 252677 0.01 0.2 43 • - 375 2.0945^ 0 005 0.05 2.3528 3 5802 4 2002 •'• ' 3 8 6 0.05- 0.077935 0 01 0.2 44 0.7631 0.9452 0.0403 0 05 1.1834 2.3506 5.2632 6.1738 0.0245 0 036387 3 3377 2 83896 45 11 7912 13 8644 0 3 5 2 1 „ . 0 05 6 5273 8 5551 13.6343 14.8776 0.1578 0.192252 0 01 0.2 46 1.9490 2.2836 0.005 0.05 2-2000. 3 6628 6.8745 7 6417 0.0243 0.03401.6 0.01 02 47 2.6606 3.1561_ 0.005 0.05 2 0375 3.4918 6.9664 £ 7 8 5 5 0.0305 0 0031 0.041484,_ 0.01 0.2 48 0 2784 0 5542 0.005 0 05 0.2500 1.3856 2 3448 3 6827 0 025 0 01 0.2 49 not-tested . 5127 not-tested 0.05 not-tested 4.0541 not-tested 7.3990 not-tested 0 083678 not-tested 0.2 50 2 7400 3 2137 0.0770 C0865 1.7853 3.1990 6.6774 7.3438 0.0287 0.039374 0.0155 , 02 51 ^ 2.6140 3.0476 0.005 0 05 2.2367 3 7751^ 6.5313 7.1413 0.0254 0 035176 0.01 . 52 0 5486 0 6375 0.005 0.05 0 2500 1 4083 3.6356 4 0209 0.0072 0 025 0 01 02 53 4.4700 6.6693 0 005 0.05 4.1536 6.3076 9.7111 11.5429 0 1050 0.122516 0.0564 0.2 54 3.7018 4 3504 0.0261 0 05 11 5674 14 2297 7.0370 . 7.8952 , 0 0428 0.055521 0 01 02 55 2 9806 M97 0.0104 0.05 8 0421 10.5919 7.1566 7.9401 0.0409 0.054282 0.01 0 2 56 1.8638 1 1475 0 005 0 05 27 4045 2 8069 8.2714 6 5--"."- 0 0300 0.030115 0 01 02 57 0.7477 0.8316 0.005 0.05_ _ 0.8704 1.9826 4.9096 5.2875 0 0170 0.025 0.2 58 1.7734 2 1907 0.0052 0 05 2.9163 4.9317 4 8443 6.9851 0 0675 0.093318 0 0530 0.2 59 0.8898 " I555_ 0 005 0 05 0.8845 2 1478 4.2477 4.8319 0.0149 0.02587 0 01 0.2 60 0.5610 0 7397 0 005 0 05 0.5347 {s§58 4.5127 4.9533 0 0138 0.025 0.0106 02 61 0.4115 0.4867 0.0374 0 0590_ 0.5196 1 6380 3.4325 ,3.6169 ^_ 0.0103 0 025 2 8968 6.67657 62 0.1999 0 2596 0.005 0.05 0 2500 1.2005 1 8131 2 5166 0 0020 0.008875 0 01 0.2 63 0.8594 1.0766 0.0236 0 05 ^ 0.8763 1.9866 5 0962 5.3070 0.0214 0.027396 0 01 0.2 64 0 7178 0.8216 0 0070 0.05 1.1379 2 4220 4 3923 4 9558 0.0242 0 033062 0 01 0.2 65 04131 04215 0 005 0 05 0.2500 1 1970 J.TJ906 3 0968 0.0102 0 0 2 5 0.0326 0.2 66 0.3264 05111 0 005 0 05 0 2500 1.4030 3 1906 4 0141 0 0084 0 025 0.01 0 2 67 0.5693 0.6450 0.0056 0.05 0.4806 1 7171 4.1248 4.6310 0.01.. 0 025 0.01 02 68 0.5032 0.7376 0.0242 0 05 0.3031 1.7519 3.9093 4.6537 0.0096 0.020338 001 ,., 0.2 69 0.4797 0.5205 0.005 0.05 0 2500 1 2997 3.8163 3 9238 0.0C74 0.025 0 0140__ 0 2 70 0 3230 0 3268 0 0167 0 05 0 2500 0 05 2 7531 2 7981 0 0078 0 025 0 01 02 71 0.5986 0 6922 0.005 0.05 11 2957 14.9502 4.8639 5.2806 0.0226 0.031754 0.01 0 2 73 1.0760 1.3199 0 1230 0 1565 1.1135 2.4491 4 5683 5.0036 0 0217 0.034213 0.01 0.2 74 0 3646 0 4763 0 0091 0 05 0.4! 2.0862 3 4708 3.9991 0.0133 0.025 0.01 0.2 75 6 7611 7.8843 0 1863 02135 12.1038 16 0526 11.0286 12 0970 0.0739 0.095122 0 01 0.2 76 0 3106 04279 0 3106 0 05 0.5793 2.4530 4 4C45 6.2247 0 0149 0.030519 0.1472 0.2 77 21.8342 25 7771 0 0692 0.05 573.9310 588 9150 7.0721 8.2643 0 2805 0.338554 0.01 0.2 79 2.7572 1.6204 0.005 0.05 2.0155 5.1068 5.8601 6.3053 0.0376 0.036044 0.01 0.2 115 Well 50 m Buffer 100 m Buffer 200 m Buffer Drainage Texture Geology Surficial Parent Number % For % Rur %Ag % Urb % For % Rur % Ag % Urb % For % Rur % Ag % Urb Code code Code Texture Material 1 0.0 80.3 4.5 00 0.0 55.1 12.2 00 00 315 14 3 00 4 3 4 2 26.2 0.0 73.8 0.0 43.0 0.0 40.0 0.0 32.7 0.0 30.3 0.0 4 3 1 3 : 3 00 0.0 00 59 5 2.1 0.0 00 46 0 1.5 0.0 0.0 43 3 •LL 4 3 i J HlillSI 4 4 0.0 48.4 39.9_ _0.0_ 0.0 ^ 27.7 43 1 0.0 0.0 17 2 37 6 3.9 4 3 1 3 4 5 0.0 1 9 17.0 151 5 0.0 6.2 17.2 75.6 0.0 20.2 23.2 34 8 IHHHI HElllB HiniM 4 6 0.0 52 0.0 94 8 _0.0 13.7 . .IP/4. 69.7 00 16.7 17.9 35.9 4 3 1 3 4 7 0.0 58 2 0.0 22 8 0.0 174 0.0 49 0 1 5 80 38 45.3 IHIH H i l l 8 00 00 26 1 67.3 0.0 44.7 44.2^  78 21 5 34 3 32.8 4 3 1 3 4 9 73 4 0.0 10.6 0.0 47.4 00 199 0.0 20.9 9.0 28.8 0.0 S H I Bllllf i 3 4 10 00 1 9 17.0 96 J6.1 11 0 21.7 50.8 13.0 12 8 36 1 36.1 4 3 1 3 4 11 00 7.5 0 0 49 0 00 ililll 00 34.0 4.7 13.9 2.5 28 5 H S 1 BlIHI 4 12 0.0 5.4 0.0 69.7 2.2 21 8 0.0 38 2 8.2 13 4 7.4 26.7 5 5 1 3 4 14 0.0 51.8 37.4 0.0 0.0 21.0 71.4 00 00 6.6 88.9 0.0 4. 3 ..LA. . 4 15 _ o..o_ 59.2 0.0 00 0.0 20.7 32 0 0.0 JD.O JLJL 4 7 ?. OC .1 1 1 3 5 0.0 60 3 39 7 00 00 31.4 63 7 00 00 0.0 83.4 12.1 IS4 llllllll 4 17 0.0 58 1 31.7 00 0.0 22.6 45.7 o.q_ 4.5 8.8 41.8 00 4 3 ^ 1 3 4 18 0.0 00 94 0 00 00 0.0 95.2 0.0 00 9.5 85 5 O C 1IHB IBIB 19 0.0 J9_3.7 4.0 00 0.0 49.3 28.0 0.0 0.0 0.0 0 0 4 3 1 3 4 20 0.0 67.0 33.0 0.0 00 19.7 74.9 00 1 7 14.2 65.7 09 llllill 4 21 0.0 60.9 . P-9_ 0.0 24.1 74 5 0.0 0.0 12 7 74 6 5.1 1 2 1 3 4 22 00 00 14 5 76 4 32 00 34 6 56 3 68 9 5 48 2 15.1 4 23 0.0 95.9 0.0 0.0 0.0 51.0 25.2 00 00 19.8 60.9 O.C 4 1 3 24 00 45.5 54 5 00 0.0 21.4 78.6 00 0.0 12.5 Z. 69.9 0.0 HfiBIIIl IMliil 3 4 25 0.0 71.7 0.0 00 0.0 33.8 14 1 00 0.0 21.2 41.4 0.0 1 2 1 3 4 26 00 f W " ' — — ™ " 29.7 45.0 0.0 00 20.6 65 3 0.0 0.0 22 4 68 7 0.0 BfiBiltf H H H 6 27 0.0 45.0 42.4 00 0.2 47 5 43.5 0.0 13.2 25 7 56 6 0.0 2 2 1 6 28 0.0 68.3 21 2 00 1 4 47.5 30 5 00 164 19 8 49 0 O C llBlllllf B i l l l 6 29 65 7 0.0 1.4 00 63.4 0.0 7 6 0.0 51.2 0 1 26.5 ... P5~ 5 5 5 4 5 30 0.0 86.0 2.0 00 00 74 3 170 0.0 1 3 63 9 30 4 0.0 IIIIHII 111B1I HIHil .""4 5 31 JO.O J99J3 0.0 0.0 0.4 76.1 14.7 00 72 50.9 30.0 1.8 5 5 4 • 32 100 0 00 00 00 76 1 48 12 6 00 58 0 12 4 25 7 00 BBS!!! IBilli 11BII1I 1 33 100.0 0.0 00 00 100 0 0.0 0.0 00 91.5 0.0 3.4 00 5 5 3 5 • 34 5.0 82.7 123 00 24.5 64 1 11.4 0.0 33 6 46.6 16 3 00 IBIllli l l l i i i l 6 35 0.0 0.0 100.0 0.0 1.1 8.0 86.7 0.0 _ 18.8 20 9 53.4 00 5 5 5 4 36 57.0 43.0 0.0 00 41 3 58 7 00 0.0 53.1 45 8 0.0 00 niiBif BUllI n m 7 37 1.6 98 4 0.0 00 32 8 67.2 00 00 65 4 33.8 0.0 5 4 4 38 56.2 40 6 00 00 42 5 51 8 0.0 0.0 42 9 52.9 0.0 0.0 llpllll .L&4 3 39 0.1 99.9 0.0 0.0 37.7 62.3 0.0 0.0 46.2 52.0 0.0 0.0 4 3 4 4 3 1 1 6 Well 50 m Buffer 100 m Buffer 200 m Buffer Drainage Texture Geology Surficial Parent Number % For % Rur % Ag % Urb % For % Rur %Ag %Urb % For % Rur %Ag % Urb Code code Code Texture Material 40 19.8 31.1 37.5 0.0 51.2 11 3 25.6 5.4 50.4 .J4.-9 37.8 166 1 2 5 1 2 41 5.1 94 6 0 0 0.0 28.9 52 7 10.8 0.0 48.8 28.5 16.9 00 1 2 5 4 2 42 0.0 0.0 0.0 100 0 04 12 1 0 3 81.9 22.7 24 5 75 46 4 HiMll m m IIIIBIIE 2 43 0.0 78.6 20 1 0.0 7 9 56.9 14.1 15.6 ...23.? J29.4 18.8 24.6 2 5 1 2 44 58.4 41 6 0.0 00 61 8 33 5 3 0 0.0 84.8 124 00 0.0 IHlilll H U H H1HI 1 45 50.9 43.4 0 0 00 34.5 59.2 00 00 49.1 47.6 00 00 3 _2_ 2 2 1 46 82.6 17.4 0.0 0.0 88.9 11.1 00 0 0 83.3 14.1 00 0.0 lUiiilt HiBlll IBI^I Il l l iH 1 47 59.8 40 2 0 0 0.0 66.3 31.0 DO 0 0 76.9 13.9 0.0 00 3 2 2 2 1 48 jjjj 90 8 9.2 0.0 00 76.5 23 5 0.0 0.0 72.0 28.0 00 0.0 1 49 _ 3 9 . - l . 60 4 0.0 00 51.9 42 4 3.0 0.0 50.4 38.8 0.0 00 3 2 2 2 1 50 H 25.0 62 3 0 0 0.0 39.1 53.8 0.0 0 0 49 2 47 1 00 00 IBI1I1I BIBB!! 1 51 94.6_ 54 00 0.0 61.5 33.4 0 0 0.0 55.6 _55.5 00 0.0 3 2 ^ 2 2 1 52 100.0 0.0 0.0 0.0 94.8 52 0.0 0.0 67.8 26 0 00 0.0 6 53 100.0 0.0 0.0 0.0 810 19.0 0 0 0.0 82.1 17.2 0.0 31 2 0.0 3 2 2 • 54 7.6 0 0 92 4 00 45 2 00 54 5 0 0 58.2 1.4 0.0 1B1II11 1 55 44 7 43 1 9.5 0.0 38.9 20.3 26.2 0.0 47.8 84 33 5 0.0 5 3 4 4 • 56 mi 08 91 6 0.0 00 194 73.0 0 0 0.0 44.0 78 6 00 00 BMIIil 1M11I11 1 57 71 9 0 0 28.1 J3.0 63.3 8.1 28.5 0.0 58.8 8.4 32.8 00 3 2 • 58 97.6 0.0 0 0 00 87 0 7 8 0.0 0.0 81 1 15.9 00 0.0 1HMIH lillllll HllilH; llll^^B 1 59 74.3 0.0 0 0 12 1 54.3 0.0 0 0 24.1 47.0 5.3 13.5 21.0 2 5 4 . 60 34.3 65 7 0.0 00 73 6 23 1 00 00 85.0 124 00 00 liBRl! Bl l l l l 1 C1 86.2 0.0 0.0 0.0 71.1 00 0 0 0 0 57.6 5.0 0.0 00 5 5 5 4 5 62 00 100 0 0 0 00 96 7 2 1 00 00 90.7 84 00 00 lillllll llilllH N/A N/A 5 63 88 1 2 1 00 a o 82.7 9.8_ 0.0 0.0 87.3 65 2 7 0.0 2 N/A N A 1 64 65.6 34 4 0.0 0.0 59.2 35 9 0.0 0.0 61.0 36 0 00 00 HllilHII H i l l l N/A N/A • - 1 G5 93.2 0 0 0 0 0.0 JJL0_ 0.0 _0.0 0.0 64.8 19.3 00 0.0 5 5 N A N/A 5 66 mi 4.9 95 1 0 0 0.0 29.8 67 6 0.0 " 0.0 57.3 32 0 0.0 00 IIBK N/A N/A 5 67 0.0 100.0 0.0 _0.0 9.9 90.1 0.0 0.0 29.2 69.3 _0.0 00 3 2 N/A N A 1 68 HI 8.7 S4 9 0.0 00 48.8 47 0 0.0 0.0 61 7 36 1 00 0.0 EEiiB N/A N/A 1 69 48.8 51.2 0.0 0.0 75.3 21.9 0.0 0.0 73.6 22.5 00 0.0 5 5 N/A N/A 5 70 0.0 100 0 0.0 00 100.0 00 0 0 0.0 93.1 25 00 0.0 5 IBIHII N/A N/A 5 71 43.7 56 3 0 0 00 61.5 34 9 0 0 0 0 71 8 ^ 23.5 0.0 0.0 2 3 N A N.A 6 73 00 100 0 0 0 00 28.1 71.9 0 0 0.0 58 4 39 3 00 0.0 BHl l l N/A N/A 5 74 75.2 24 8 0 0 00 90.9 9.1 0 0 0 0 81 6 _J2.3 0.0 0.0 5 5 N/A N/A 5 75 29 3 46 1 7 4 00 43 2 20 9 28.4 0 0 53 5 13 1 30 1 00 llllBlllll 11B1I! 5 76 100.0 0 0 0 0 _ a o _ 96.0 0.0_ 0.0 0 0 88.4 8.4 00 00 3 2 2 2 • 77 13.9 74.3 0.0 00 35 2 55.6 2.5 0.0 53.5 34.5 87 0.0 131I1M BnniB' JlBllllI! 5 79 0.0 38.3 54.0 0.0 4.7 23.6 63.6 0.0 15.7 23.7 56.4 0.0 2 2 5 1 6 117 Append ix 9 - R a w S t ream Data Size and Location %For %Ag %Wet/Rip %Clear100%Other100 Forest Ag Area Clearing Wet/Rip Other Area Total Area Station X-COR Y-COR 100 m 100 m 100 m m m Area (Ha) (Ha) Area (Ha) Area (Ha) (Ha) (Ha) Length (km) 1 556867.59 5446584.15 52.90 31.00 6.10 8.70 1.30 88.97 62.75 20.85 10.82 3.37 186.75 8.92 2 556001.87 5448433.14 98.00 0.00 0.00 2.00 0.00 52.29 0.00 1.19 0.00 0.27 53.76 2.551 4 556127.07 5449966.08 97.80 0.00 0.00 1.40 0.70 38.91 0.00 0.56 0.00 0.29 39.76 1.911 5 555977.05 5451000.45 94.50 1.70 0.00 3.60 0.20 221.13 3.90 8.45 0.00 0.50 233.98 10.479 6 556456.87 5452709.80 98.80 0.00 0.00 0.60 0.50 41.94 0.00 0.26 0.00 0.29 42.43 2.132 7 557017.22 5455038.22 98.20 0.00 0.00 0.90 0.90 31.39 0.00 0.28 0.00 0.30 31.96 1.471 8 555032.33 5452230.37 79.20 16.90 0.00 2.60 1.20 19.87 4.25 0.66 0.00 0.30 25.07 1.108 9 555359.08 5452233.43 77.60 8.70 0.00 9.90 3.70 30.30 3.40 3.89 0.00 0.28 39.04 1.833 10 554820.10 5452228.85 88.79 3.30 0.00 5.90 2.00 51.67 1.92 3.43 0.00 1.17 58.19 2.789 11 554806.36 5451802.86 79.58 4.70 0.00 6.07 9.60 157.22 9.31 11.99 1.00 13.18 187.70 9.855 12 554314.72 5451769.27 96.20 3.10 0.00 0.20 0.40 37.71 1.22 0.09 0.00 0.18 39.27 1.827 13 553476.49 5449758.43 61.40 20.00 0.00 11.00 6.70 67.50 5.53 4.45 0.00 0.57 78.05 3.925 14 554557.49 5449772.17 69.33 18.85 1.29 7.67 2.86 382.43 103.99 42.31 7.11 15.76 551.60 40.738 15 554504.05 5449805.76 62.10 26.70 1.30 8.50 1.20 115.45 49.68 15.89 2.51 2.40 185.89 9.929 16 554814.00 5450051.58 76.30 18.70 0.80 3.30 0.80 288.40 70.72 12.74 3.05 3.05 377.96 19.093 17 554823.16 5448779.73 68.90 21.10 1.80 6.10 2.09 725.87 222.73 64.29 18.98 22.01 1053.88 56.24 18 554830.79 5448285.04 2.10 78.20 4.20 8.60 6.60 0.21 7.46 0.83 0.40 0.64 9.52 0.337 19 555646.12 5448172.05 69.21 20.60 1.99 5.90 2.30 784.19 232.97 67.28 22.55 26.09 1133.07 60.446 118 Temperature (Degrees Ce lc ius ) J u l y 2, J u l y 24, Sep t 20, Oct 16, Nov 19, D e c 19, Stat ion M a y 16, 2002 2002 2002 A u g 22, 2002 2002 2002 2002 2002 J a n 30, 2003 Mar 12, 2003 A v g - Dry A v g - Wet 1 15.00 17.00 25.80 20.20 15.30 12.70 9.80 6.60 8.00 6.90 17.67 7.83 2 8.00 12.00 17.50 14.20 13.10 11.30 9.90 8.20 7.80 6.00 12.68 7.98 4 8.00 11.30 Skipped 15.70 Skipped 11.40 10.20 7.80 7.50 6.40 11.60 7.98 5 10.50 12.40 27.00 16.80 15.80 9.00 9.90 8.00 ' 8.10 6.40 15.25 8.10 6 8.70 13.00 23.40 16.20 12.20 9.80 9.90 6.50 7.10 5.90 13.88 7.35 7 7.00 10.70 Dry Dry Dry Dry 11.00 7.60 6.70 5.70 8.85 7.75 8 9.80 10.80 12.60 10.30 11.40 8.40 10.50 7.00 7.70 6.40 10.55 7.90 9 9.60 10.50 31.00 10.40 11.50 8.60 10.50 7.10 8.10 6.70 13.60 8.10 10 9.30 10.80 13.50 10.50 10.40 8.70 10.50 7.20 7.90 6.40 10.53 8.00 11 7.40 14.00 18.50 13.10 12.20 9.60 9.90 6.60 7.70 6.30 12.47 7.63 12 9.70 13.30 20.50 18.30 14.50 12.00 11.00 6.20 6.90 6.00 14.72 7.53 13 11.50 12.70 19.40 17.50 13.00 11.20 10.00 7.10 7.90 6.50 14.22 7.88 14 13.00 15.80 19.90 19.00 16.10 10.70 10.90 6.40 7.50 6.30 15.75 7.78 15 14.00 16.80 26.40 21.10 13.10 12.00 9.50 6.00 7.20 6.40 17.23 7.28 16 13.50 19.80 23.60 24.00 12.00 11.30 10.90 6.60 8.30 6.40 17.37 8.05 17 13.40 14.70 27.20 20.40 15.30 11.90 10.00 6.60 7.80 6.40 17.15 7.70 18 19.00 23.40 28.70 22.40 16.30 14.30 10.60 5.70 7.10 6.20 20.68 7.40 19 12.00 16.90 26.70 20.40 14.80 11.60 10.70 6.40 7.80 6.40 17.07 7.83 119 Nitrate (mg/L) M a y 16, A u g 22, Nov, 19, Stat ion 2002 J u l y 2, 2002 2002 O c t 16, 2002 2002 D e c 19, 2002 J a n 30, 2003 Mar 12, 2003 M a y 5, 2003 A v g - Dry A v g - Wet 1 0.06 0.02 0.02 0.00 0.94 0.48 0.40 0.34 0.03 0.05 0.44 2 0.17 0.25 0.28 0.48 0.41 0.37 0.21 0.20 0.20 0.30 0.28 4 0.17 0.23 0.27 0.43 1.25 0.60 0.38 0.39 0.23 0.27 0.57 5 0.32 0.28 0.20 0.27 1.45 0.78 0.60 0.52 0.37 0.27 0.74 6 0.19 0.15 0.16 0.27 0.38 0.36 0.25 0.25 0.17 0.19 0.28 7 0.18 0.12 DRY DRY 0.17 0.30 0.02 0.14 0.09 0.15 0.14 8 0.22 0.20 0.16 0.20 1.02 0.56 0.52 0.56 0.43 0.19 0.62 9 0.43 0.42 0.20 0.50 0.97 0.39 0.37 0.47 0.21 0.39 0.48 10 0.29 0.26 0.47 0.26 1.43 0.68 0.59 0.64 0.28 0.32 0.72 11 0.26 0.25 0.23 0.35 0.77 0.54 0.35 0.32 0.32 0.28 0.46 12 0.18 0.20 0.35 0.30 0.94 0.47 0.39 0.41 0.21 0.26 0.48 13 0.56 0.51 0.41 0.47 2.51 1.89 1.52 1.43 0.92 0.49 1.65 14 0.29 0.23 0.19 0.36 1.29 1.11 0.87 0.91 0.37 0.27 0.91 15 0.31 0.17 0.04 0.09 1.22 1.21 0.91 1.05 0.45 0.16 0.97 16 0.31 0.13 0.09 0.18 1.76 0.88 0.50 0.45 0.26 0.17 0.77 17 0.29 0.04 0.28 0.34 0.95 0.78 0.56 0.50 0.33 0.24 0.62 18 0.10 0.02 0.02 0.12 0.82 0.66 0.38 0.39 0.06 0.06 0.46 19 0.00 0.24 0.27 0.34 0.96 0.82 0.61 0.56 0.33 0.21 0.65 120 Conductivity (nS/cm) May 02, May 16, July 24, Aug 22, Sept 20 Nov 19, Station 2002 2003 July 2, 2002 2002 2003 2002 Oct 16, 2002 2002 Dec 19, 2002 Jan 30, 2003 Mar 12, 2003 Avg - Dry Avg - Wet 1 71.00 80.00 105.00 95.60 100.70 82.80 84.00 49.40 47.40 46.60 34.60 88.44 44.50 2 67.00 29.00 32.50 36.00 41.20 43.90 49.10 23.00 31.40 . 25.70 23.10 42.67 25.80 4 26.00 27.70 28.50 skipped 37.20 skipped 38.10 31.00 31.10 28.00 25.90 31.50 29.00 5 36.00 33.00 40.60 42.70 22.10 51.50 54.60 34.00 34.90 32.00 28.30 40.07 32.30 6 28.00 31.00 35.00 41.60 45.40 45.90 50.10 27.00 34.40 31.70 29.60 39.57 30.68 7 10.00 15.50 20.60 Dry Dry Dry Dry 13.70 26.10 17.36 17.91 15.37 18.77 8 137.00 147.00 143.50 146.50 151.00 149.00 163.00 42.00 123.60 65.40 51.30 148.14 70.58 9 83.00 89.00 86.50 87.70 89.30 86.60 93.20 31.00 71.00 112.80 89.10 87.90 75.98 10 87.00 89.00 90.90 100.10 103.30 100.00 108.00 37.00 61.20 55.70 43.30 96.90 49.30 11 32.00 44.00 51.70 150.00 66.50 75.40 271.00 61.00 44.20 36.30 32.10 98.66 43.40 12 Skipped 14.30 15.20 21.10 23.70 22.20 23.30 17.00 14.50 13.91 13.00 19.97 14.60 13 43.00 12.00 45.80 55.20 56.90 59.60 66.50 35.00 35.60 32.30 27.10 48.43 32.50 14 61.00 73.20 85.30 88.70 125.40 151.40 106.70 59.00 49.70 52.90 36.00 98.81 49.40 15 81.00 84.50 92.80 78.20 160.60 115.90 235.00 58.00 49.60 54.30 35.10 121.14 49.25 16 72.00 81.00 83.70 100.00 120.50 108.10 109.20 70.90 76.30 69.70 49.00 96.36 66.48 17 62.00 71.50 79.80 91.40 102.40 94.80 104.90 37.00 57.80 52.50 42.50 86.69 47.45 18 136.00 159.00 149.00 168.00 196.70 235.00 244.00 57.00 90.00 90.10 60.30 183.96 74.35 19 67.00 73.00 81.90 95.10 107.00 98.50 106.10 40.00 61.10 56.50 47.90 89.80 51.38 121 Appendix 10. Dendogram Used to Determine Clusters in Figure 25 32 64 60 34 44 57 59 68 69 52 74 67 61 66 65 70 76 48 62 17 54 55 50 41 79 51 47 58 71 14 56 28 31 46 35 63 33 43 73 27 29 15 75 19 53 1 11 12 9 21 6 16 24 10 18 83 5 81 T X L 3-_zr T l 20 23 _L 82 —I 4 122 

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.831.1-0091590/manifest

Comment

Related Items