Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

An examination of factors affecting vegetation establishment at the Kitsault minesite Price, William Andrew 1989

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

Item Metadata

Download

Media
831-UBC_1989_A1 P74.pdf [ 33.07MB ]
Metadata
JSON: 831-1.0098277.json
JSON-LD: 831-1.0098277-ld.json
RDF/XML (Pretty): 831-1.0098277-rdf.xml
RDF/JSON: 831-1.0098277-rdf.json
Turtle: 831-1.0098277-turtle.txt
N-Triples: 831-1.0098277-rdf-ntriples.txt
Original Record: 831-1.0098277-source.json
Full Text
831-1.0098277-fulltext.txt
Citation
831-1.0098277.ris

Full Text

AN EXAMINATION OF FACTORS AFFECTING VEGETATION ESTABLISHMENT AT THE KITSAULT MINESITE By WILLIAM ANDREW PRICE B.Sc, McGill University, 1980 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES (Department of Soil Science) We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA October 1989 © William Andrew Price, 1989 In presenting this thesis in partial fulfilment 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. Department of The University of British Columbia Vancouver, Canada Date DE-6 (2/88) ABSTRACT The end l a n d use o b j e c t i v e f o r most mines i n B r i t i s h Co lumbia i s a v e g e t a t i o n c o v e r o f e q u a l p r o d u c t i v i t y t o t h a t which e x i s t e d p r i o r t o m i n i n g . The s u b j e c t o f t h i s s tudy was the K i t s a u l t m i n e s i t e i n n o r t h c o a s t a l B . C . . The p r o j e c t had two components. The o b j e c t i v e o f t h e f i r s t was t o i d e n t i f y p l a n t and s o i l f a c t o r s impeding f o r e s t deve lopment . V i g o r o u s p l a n t growth i n d i c a t e d t h a t a number o f m a t e r i a l s and methods can be used t o a c h i e v e a s u s t a i n e d v e g e t a t i v e c o v e r on the was terock dumps. S t u d i e s o f s i m i l a r n a t u r a l s u b s t r a t e s ( r e c e n t l y exposed moraines i n S . E . A l a s k a ) showed t h a t l i t t e r and N a d d i t i o n s were the main , d r i v i n g f o r c e s f o r p l a n t and s o i l deve lopment . The two p l a n t s p e c i e s p r o d u c i n g the h i g h e s t amounts o f l i t t e r and N on t h e was terock dumps were S i t k a a l d e r and b i r d s f o o t t r e f o i l . W h i l e good p l a n t growth was a c h i e v e d on t h e dump benches , on the dump s l o p e s i t was impeded by t h e absence o f s o i l - s i z e d p a r t i c l e s . The b e s t source o f such p a r t i c l e s was t h e incompetent w a s t e r o c k . The o b j e c t i v e o f the second p a r t o f t h e s t u d y was t o e v a l u a t e the l o n g term performance o f the incompetent w a s t e r o c k , used as a source o f f i n e s , on s l o p e s a t the a n g l e o f r e p o s e . The h i g h e r p r o p o r t i o n o f f i n e p a r t i c l e s i n the incompetent was terock appeared t o r e s u l t from t h e r e l a t i v e l y l a r g e p r o p o r t i o n o f s e r i c i t e and c a l c i t e , most o f which i i i ended up i n the < 2mm f r a c t i o n . The modal c o m p o s i t i o n o f t h e incompetent was terock c o a r s e fragments was 90% q u a r t z and K f e l d s p a r . The r e s i l i e n c e o f these m i n e r a l s t o w e a t h e r i n g sugges t s t h a t f u r t h e r f r a g m e n t a t i o n , beyond t h a t o b s e r v e d i n t h e f i r s t few y e a r s , w i l l be l i m i t e d , and t h u s t h e v e n e e r o f incompetent was terock s h o u l d m a i n t a i n the a n g l e o f repose and m a i n t a i n good d r a i n a g e . W i t h r e g a r d s t o n u t r i e n t a v a i l a b i l i t y , the incompetent was terock appeared t o be a b e t t e r s o u r c e o f C a , K, Mg, and P t h a n any o f the o t h e r w a s t e r o c k t y p e s o r the m i n e r a l l a y e r s i n a d j a c e n t n a t u r a l s o i l s . Of the t r a c e e lements a n a l y s e d , l e v e l s i n t h e incompetent was terock were no h i g h e r t h a n i n t h e o t h e r w a s t e r o c k t y p e s . iv TABLE OP CONTENTS Page Abstract : i i Table of Contents * v L i s t of Tables ' .' L i s t of Figures x v i Acknowledgements x v i i I. INTRODUCTION 1 1. Glossary . .' 1 2. Overview of the Project 3 3. Description of Study S i t e 6 3 .1 Location 6 3.2 Geology 7 3.3 Climate 8 3.4 Topography and Drainage 8 3.5 Vegetation 8 3.6 S u r f i c i a l Materials and S o i l s 10 3.7 Mine History and Mining Method 11 3.8 Previous Reclamation and the Present Reclamation Objective 12 I I . PLANT AND SOIL FACTORS THAT COULD LIMIT THE RATE OF RECLAMATION 14 1. Objective 14 2. Li t e r a t u r e Review 15 2.1 Properties of Wasterock 15 2.2 S u i t a b i l i t y of Wasterock for Use as a S o i l 18 2.3 Mine Reclamation Regulations 20 V 2.4 R e c l a m a t i o n R e s e a r c h 21 2 .5 R e c l a m a t i o n Research a t K i t s a u l t 30 2.6 S o i l Development on Mine Wastes 31 2.7 N a t u r a l P l a n t S u c c e s s i o n . . . 36 2.8 The E a r l y Stages o f N a t u r a l S o i l Development 41 2 .9 W e l l Deve loped S o i l s 45 3 .0 Summary 48 3. M a t e r i a l s and Methods 51 3 .1 D e s c r i p t i o n o f Study S i t e s 51 3 . 1 . 1 S o i l Resources 51 3 . 1 . 2 P l a n t Growth 56 3.2 F o l i a g e and S o i l Sampl ing 56 3.3 L a b o r a t o r y A n a l y s e s 64 3 . 3 . 1 S o i l Samples 64 3 . 3 . 2 P l a n t Samples 65 3.4 Data A n a l y s i s 65 4. R e s u l t s and D i s c u s s i o n 67 4 .1 S o i l Resources 67 4 . 1 . 1 U n t r e a t e d Dumps 67 4 . 1 . 1 . 1 P h y s i c a l P r o p e r t i e s . . . . 67 4 . 1 . 1 . 2 C h e m i c a l P r o p e r t i e s . . . . 77 4 . 1 . 2 F i e l d T r i a l s 90 4 . 1 . 1 . 1 S u r f a c e C o n d i t i o n s 90 4 . 1 . 1 . 2 P h y s i c a l P r o p e r t i e s . . . . 92 4 . 1 . 1 . 3 C h e m i c a l P r o p e r t i e s . . . . 100 v i 4.2 P l a n t Growth 109 4 . 2 . 1 G r a s s and Legume Growth i n the Bench T r i a l s 113 4 . 2 . 1 . 1 T r i a l 7 0 . 1 : S p e c i e s / /Amendment 113 4 . 2 . 1 . 2 T r i a l 8 2 . 1 : S p e c i e s / Amendment 128 4 . 2 . 2 Woody P l a n t Growth i n the Bench T r i a l s 135 4 . 2 . 2 . 1 T r i a l 7 0 . 3 : C o n i f e r S p e c i e s 135 4 . 2 . 2 . 2 T r i a l 7 7 . 1 : S i t k a A l d e r 137 4 . 2 . 2 . 3 T r i a l 8 2 . 1 : P i n e and A l d e r 139 4 . 2 . 3 N a t u r a l P l a n t I n v a s i o n 144 4 . 2 . 3 . 1 N a t u r a l P l a n t I n v a s i o n o f U n t r e a t e d S u r f a c e s . . 144 4 . 2 . 3 . 2 N a t u r a l P l a n t I n v a s i o n o f T r i a l 70 .1 146 4 . 2 . 4 E v a l u a t i n g the Long Term Performance o f M a t e r i a l s and Methods T e s t e d i n the F i e l d T r i a l s 152 4 . 2 . 5 S l o p e T r i a l s 157 4 . 2 . 5 . 1 T r i a l 7 5 . 1 : W a s t e r o c k . . 158 4 . 2 . 5 . 2 T r i a l 8 1 . 1 : Overburden . 159 4 . 2 . 5 . 3 T r i a l 8 2 . 1 : Incompetent Wasterock 164 5. Summary. 167 6. L i t e r a t u r e C i t e d 175 v i i III EVALUATING THE LONG TERM PERFORMANCE OF THE INCOMPETENT WASTEROCK, USED AS A SOURCE OF FINES, ON SLOPES AT THE ANGLE OF REPOSE 183 1. Introduction 183 1.1 Objective 183 1.2 Lit e r a t u r e Review 186 1.2.1 Properties of Podzolic S o i l s .... 186 1.2.2 Methods of Simulating Weathering 196 2. C h a r a c t e r i s t i c s of Rock Types found i n the Waste 199 2.1 Objective 199 2.2 Materials and Methods 199 2.2.1 Sample Selection 199 2.2.2 Sample Analysis 199 2.2.3 Data Analysis 203 2.3 Results and Discussion 2 04 2.3.1 Grain Size 204 2.3.2 Total Mineralogy 204 2.3.3 Major Elements 213 2.3.4 < 2 urn Mineralogy 215 2.3.5 Trace Elements 217 2.4 Summary 221 3. C h a r a c t e r i s t i c s of Weathered Wasterock 223 3.1 Objective 22 3 3.2 Materials and Methods 223 3.2.1 Sample S e l e c t i o n . . 223 3.2.2 Sample Analysis 223 3.2.3 Data Analysis 224 v i i i 3.3 R e s u l t s and D i s c u s s i o n 225 3 . 4 . 1 pH and O r g a n i c Carbon 225 3 . 4 . 2 M i n e r a l o g y and M a j o r Elements Content o f < 2mm F r a c t i o n 225 3 . 4 . 3 < 2 um M i n e r a l o g y 231 3 . 4 . 4 P a r t i c l e S i z e 231 3 . 4 . 5 T r a c e Elements c o n t e n t o f < 2mm F r a c t i o n 234 3 . 4 . 6 E x t r a c t a b l e Elements 23 6 3 .5 Summary 242 4. P r o p e r t i e s o f N a t u r a l S o i l s A d j a c e n t t o t h e M i n e s i t e 244 4 .1 O b j e c t i v e s 244 4.2 M a t e r i a l s and Methods 244 4 . 2 . 1 Sample S e l e c t i o n 244 4 . 2 . 2 S i t e D e s c r i p t i o n 245 4 . 2 . 3 Sample A n a l y s i s 245 4.3 R e s u l t s and D i s c u s s i o n 249 4 . 3 . 1 S i t e and P r o f i l e D e s c r i p t i o n s . . . 249 4 . 3 . 2 E x t r a c t a b l e Elements 254 4 . 3 . 3 Coarse Fragment and < 2 mm M i n e r a l o g y 259 4 . 3 . 4 Heavy M i n e r a l s 266 4 . 3 . 5 P a r t i c l e S i z e 268 4 . 3 . 6 M a j o r Element C o m p o s i t i o n 272 4 . 3 . 7 M i n o r Element C o m p o s i t i o n 276 4 . 3 . 8 2-20 um and < 2 um M i n e r a l o g y . . . 281 4.4 Summary * 284 i x 5. S i m u l a t e d Weather ing . 288 5.1 I n t r o d u c t i o n 288 5.2 O b j e c t i v e . 288 5.3 M a t e r i a l s and Methods 289 5 . 3 . 1 Samples 289 5 .3 .2 S o x h l e t Methods and Sample A n a l y s i s 289 5.4 R e s u l t s and D i s c u s s i o n 291 5 . 4 . 1 Weight Loss and C a l c i t e D i s s o l u t i o n 291 5 . 4 . 2 P a r t i c l e S i z e 294 5 . 4 . 3 2-20 um and < 2 um M i n e r a l o g y . . . 296 5 . 4 . 4 M a j o r Element C o m p o s i t i o n 298 5 . 4 . 5 T r a c e Element C o m p o s i t i o n 306 5 .5 Summary. 309 6. L i t e r a t u r e C i t e d 311 IV CONCLUSIONS 317 V APPENDICES 329 LIST OF TABLES PART II Page 1.1 Surfaces sampled and number of samples analysed f o r untreated wasterock 53 1.2 Descriptions of the wasterock dumps and the overburden sampled i n t h i s study 54 1.3 Treatments sampled and number of samples analysed f o r the f i e l d t r i a l s 57' 1.4 A l i s t of the t r i a l s t e s t i n g plant growth. .. 58 1.5 The L a t i n names of agronomic species tested at K i t s a u l t 59 1.6 Seed mixes applied on the bench t r i a l s 60 1.7 Seed mixes applied on the slope t r i a l s 61 1.8 The rate at which f e r t i l i z e r was applied i n the agronomic f i e l d t r i a l s 62 1.9 Surface conditions i n 1980 on areas of untreated wasterock and overburden abandoned i n 1972 68 1.10 S o i l p hysical properties of the untreated wasterock dumps 69 1.11 The p r o b a b i l i t y that differences e x i s t between the physical properties of the 0-5 and the 5-10 cm depths of the untreated wasterock dumps 69 1.12 Cor r e l a t i o n c o e f f i c i e n t s f o r s o i l p h y sical properties of the untreated wasterock dumps 71 1.13 S o i l texture information f o r d i f f e r e n t s i t e s on the untreated wasterock dumps 76 1.14 S o i l chemical properties of the untreated wasterock dumps 78 x i ; 1.15 C o r r e l a t i o n c o e f f i c i e n t s among s o i l c h e m i c a l and o t h e r p r o p e r t i e s o f t h e u n t r e a t e d w a s t e r o c k dumps 80 1.16 The p r o b a b i l i t y t h a t d i f f e r e n c e s e x i s t between 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 0-5 and 5-10 cm depths o f t h e u n t r e a t e d w a s t e r o c k dumps 82 1.17 The pH and t h e c a l c i t e and o r g a n i c m a t t e r c o n t e n t s o f s e l e c t e d w a s t e r o c k samples 84 1.18 The s u r f a c e c o v e r on sampled a r e a s o f t h e f i e l d t r i a l s 91 1.19 S o i l p h y s i c a l p r o p e r t i e s o f t h e f i e l d t r i a l s 93 1.20 C o r r e l a t i o n c o e f f i c i e n t s f o r s o i l p h y s i c a l p r o p e r t i e s o f t h e f i e l d t r i a l s 96 1.21 The p r o b a b i l i t y t h a t d i f f e r e n c e s e x i s t between t h e s o i l p h y s i c a l p r o p e r t i e s o f t h e 0-5 and 5-10 d e p t h s o f t h e f i e l d t r i a l s 96 1.22 S o i l t e x t u r e i n f o r m a t i o n f o r d i f f e r e n t t r e a t m e n t s i n t h e f i e l d t r i a l s 99 1.23 S o i l c h e m i c a l p r o p e r t i e s o f t h e f i e l d t r i a l s 101 1.24 The p r o b a b i l i t y t h a t d i f f e r e n c e s e x i s t between t h e p h y s i c a l p r o p e r t i e s o f t h e 0-5 and 5-10 cm d e p t h s on t h e t r e a t e d dumps 102 1.25 C o r r e l a t i o n c o e f f i c i e n t s f o r s o i l c h e m i c a l p r o p e r t i e s o f t h e f i e l d t r i a l s 104 1.26 Av e r a g e d a t a f o r s o i l c h e m i c a l p r o p e r t i e s on s e c t i o n s o f 70F and 70P sown w i t h d i f f e r e n t seed mixes 107 1.27 S o i l p r o p e r t i e s o f t h e o v e r b u r d e n . 110 1.28 Average p e r c e n t c o v e r on d i f f e r e n t t r e a t m e n t s i n T r i a l 70.1 114 1.29 Average p e r c e n t c o v e r f o r i n d i v i d u a l agronomic s p e c i e s g r o w i n g on T r i a l 70.1 115 x i i 1.30 C o e f f i c i e n t s o f v a r i a n c e f o r d i f f e r e n t c o v e r t y p e s i n T r i a l 70.1 120 1.31 C o e f f i c i e n t o f v a r i a n c e f o r d i f f e r e n t g r a s s and legume s p e c i e s g r o w i n g on T r i a l 70.1 121 1.32 Above ground biomass and f o l i a r c h e m i s t r y d a t a from T r i a l 70.1 i n 1980 123 1.33 Above ground biomass o f s p e c i e s sampled i n T r i a l 70.1 i n September, 1981 125 1.34 Above ground biomass o f agronomic s p e c i e s i n f i e l d t r i a l s i n September, 1984. . . 125 1.35 Average p e r c e n t c o v e r o f agronomic s p e c i e s g r o w i n g i n T r i a l 82.1 133 1.36 Average h e i g h t s and a n n u a l g r o w t h o f c o n i f e r s p l a n t e d i n T r i a l 70.3 136 1.37 A l d e r g r o w t h s t a t i s t i c s from T r i a l 77.1. ... 138 1.38 A v e r a g e s u r v i v a l o f a l d e r and p i n e o v e r t h e f i r s t t h r e e y e a r s o f growth i n T r i a l 82.1 140 1.39 Average h e i g h t , and growth o f s e e d l i n g s on d i f f e r e n t t r e a t m e n t s i n T r i a l s 82.1 140 1.40 The number and h e i g h t o f woody s p e c i e s i n 1984 on u n t r e a t e d s u r f a c e s aboandoned i n 1972 145 1.41 The number o f s e e d l i n g s c o l o n i z i n g d i f f e r e n t t r e a t m e n t s i n T r i a l 70.1 i n 1982 148 1.42 The number, h e i g h t , and growth o f i n v a d i n g s e e d l i n g s t a l l e r t h a n 49 cm on d i f f e r e n t t r e a t m e n t s i n T r i a l 70.1 150 1.43 Cover o f agronomic s p e c i e s on f i n e s -c o n t a i n i n g p o r t i o n s o f T r i a l 81.1 161 1.44 P r o p o r t i o n o f < 2 mm p a r t i c l e s i n upper 10 cm o f s l o p e , t h r e e y e a r s a f t e r i t was c o v e r e d w i t h i n c o m p e t e n t w a s t e r o c k 165 x i i i PART I I I - Section 2 2.1 A n a l y s e s c a r r i e d o u t on d i f f e r e n t f r a c t i o n s o f t h e r o c k and w a s t e r o c k 200 2.2 The g r a i n s i z e d i s t r i b u t i o n i n d i f f e r e n t r o c k t y p e s 205 2.3 P r o p o r t i o n and s i z e o f d i f f e r e n t m i n e r a l s i n p o t a s s i c and in c o m p e t e n t r o c k t h i n s e c t i o n s 206 2.4 M i n e r a l o g y o f h o r n f e l s , p o t a s s i c and in c o m p e t e n t r o c k and w a s t e r o c k 207 2.5 M a j o r element c o n c e n t r a t i o n s i n t h e r o c k samples and t h e < 2 mm f r a c t i o n s o f t h e w a s t e r o c k 214 2.6 M i n e r a l o g y o f t h e < 2 um f r a c t i o n i n t h e w a s t e r o c k and t h e c r u s h e d r o c k . 216 2.7 T r a c e element c o n c e n t r a t i o n s i n t h e r o c k and t h e < 2 mm f r a c t i o n o f t h e w a s t e r o c k . ... 218 PART III - Section 3 2.8 The pH, c a r b o n a t e - C , and o r g a n i c - C l e v e l s o f t h e weathered and unweathered w a s t e r o c k 226 2.9 M i n e r a l o g y o f t h e < 2 mm f r a c t i o n s o f t h e unweathered and weathered w a s t e r o c k 227 2.10 M a j o r element c o n c e n t r a t i o n s i n t h e < 2 mm f r a c t i o n s o f t h e unweathered and wea t h e r e d w a s t e r o c k 228 2.11 M i n e r a l o g y o f t h e < 2 um f r a c t i o n s o f t h e unweathered and weathered w a s t r o c k 232 2.12 P a r t i c l e s i z e d i s t r i b u t i o n o f t h e unweathered and weathered w a s t e r o c k 233 2.13 T r a c e element c o n c e n t r a t i o n s i n t h e < 2 mm f r a c t i o n s o f t h e unweathered and weath e r e d w a s t e r o c k 235 xiv-2.14 Spearman c o r r e l a t i o n c o e f f i c i e n t s f o r s i g n i f i c a n t c o r r e l a t i o n s between l e v e l s o f e x t r a c t a b l e e l e m e n t s i n we a t h e r e d and unweathered w a t e r o c k 237 2.15 E x t r a c t a b l e element c o n c e n t r a t i o n s i n t h e < 2 mm f r a c t i o n s o f t h e w a s t e r o c k and t h e c r u s h e d (< 2 mm) r o c k samples 238 2.16 Spearman c o r r e l a t i o n c o e f f i c i e n t s f o r s i g n i f i c a n t c o r r e l a t i o n s between e x t r a c t a b l e element c o n c e n t r a t i o n s and o t h e r p r o p e r t i e s o f t h e w a s t e r o c k 239 PART I I I - Section 4 2.17 A n a l y s e s c a r r i e d o u t on samples from t h e n a t u r a l s o i l s 246 2.18 P r o f i l e d e s c r i p t i o n s f o r t h e n a t u r a l s o i l s . . 251 2.19 E x t r a c t a b l e element c o n c e n t r a t i o n s i n t h e n a t u r a l s o i l s 255 2.20 AAO e x t r a c t a b l e element c o n c e n t r a t i o n s i n t h e q u a r t z d i o r i t e s o i l ( d i f f e r e n c e i n t o t a l c o m p o s i t i o n b e f o r e and a f t e r AAO e x t r a c t i o n ) 255 2.21 E s t i m a t e d m i n e r a l o g y o f t h e c o a r s e f r a g m e n t s and < 2 mm f r a c t i o n s o f t h e n a t u r a l s o i l s 260 2.22 E s t i m a t e d m i n e r a l o g y o f t h e sand and c o a r s e s i l t f r a c t i o n s o f t h e Ae, B h f l , B f , and BC3 h o r i z o n s o f t h e q u a r t z d i o r i t e s o i l 265 2.23 Heavy m i n e r a l c o n t e n t i n s e l e c t e d h o r i z o n s o f t h e q u a r t z d i o r i t e s o i l 267 2.24 P r o p o r t i o n o f i n d i v i d u a l heavy m i n e r a l s i n t h e 3.31 g/cm3, 100 t o 50 um f r a c t i o n o f s e l e c t e d h o r i z o n s o f t h e q u a r t z d i o r i t e s o i l 269 2.25 P a r t i c l e s i z e d i s t r i b u t i o n s i n t h e < 2 mm f r a c t i o n s o f t h e n a t u r a l s o i l s 270 XV 2.26 M a j o r element c o m p o s i t i o n o f t h e c o a r s e f r a g m e n t s and < 2 mm f r a c t i o n s o f t h e n a t u r a l s o i l s 273 2.27 M i n o r element c o n c e n t r a t i o n s i n t h e c o a r s e f r a g m e n t s and < 2 mm f r a c t i o n s o f t h e n a t u r a l s o i l s 277 2.28 E s t i m a t e d m i n e r a l o g y o f t h e < 2 um and 2-20 um f r a c t i o n s o f t h e n a t u r a l s o i l s 283 PART II I - Section 5 2.29 Average w e i g h t l o s s and o t h e r p r o p e r t i e s o f t h e S o x h l e t r e s i d u e and l e a c h a t e 292' 2.30 Average p a r t i c l e s i z e d i s t r i b u t i o n a f t e r S o x h l e t l e a c h i n g . 295 2.31 E s t i m a t e d m i n e r a l o g y o f t h e < 2 and 2-20 um f r a c t i o n s o f t h e F I and GM samples b e f o r e and a f t e r 8 weeks o f S o x h l e t l e a c h i n g 297 2.32 Average major element c o m p o s i t i o n o f t h e S o x h l e t r e s i d u e s 299 2.33 Average c u m u l a t i v e and p r o p o r t i o n o f i n i t i a l m a j o r element w e i g h t r e c o v e r e d i n t h e l e a c h a t e 300 2.34 A c o m p a r i s o n o f w e i g h t l o s s e s from t h e r e s i d u e s and w e i g h t g a i n s i n t h e l e a c h a t e . .. 301 2.35 Average t r a c e element c o m p o s i t i o n o f t h e S o x h l e t r e s i d u e s 307 2.36 Average c u m u l a t i v e and p r o p o r t i o n o f i n i t i a l t r a c e element w e i g h t r e c o v e r e d i n t h e l e a c h a t e . 308 x v i LIST OF FIGURES PART I I Page 1.1 A s c h e m a t i c d iagram o f t h e K i t s a u l t mine showing the l o c a t i o n o f s i t e s examined i n t h i s s tudy 52 1.2 pH v s N / m 3 f o r the 0-5 cm depth on the u n t r e a t e d dumps (r=-0.79) 85 1.3 pH vs N / m 3 f o r the 5-10 cm depth on t h e u n t r e a t e d dumps (r=-0.83) 85 1.4 pH vs a v a i l a b l e P f o r the 0-5 cm depth on the u n t r e a t e d dumps (r=-0.79) 89 1.5 pH v s a v a i l a b l e P f o r the 5-10 cm depth on the u n t r e a t e d dumps (r=^0.90) 89 1.6 pH vs %C f o r the f i e l d t r i a l t r e a t m e n t x depth averages 102 1.7 Average agronomic c o v e r f o r the y e a r x seed mix c o m b i n a t i o n s i n T r i a l 82 .1 130 1.8 Average agronomic c o v e r f o r the s o i l t y p e x seed mix c o m b i n a t i o n s i n T r i a l 82 .1 130 1.9 Average agronomic c o v e r f o r the b l o c k x s o i l t y p e c o m b i n a t i o n s i n T r i a l 82 .1 131 x v i i ACKNOWLEDGEMENTS In c o m p l e t i n g t h i s p r o j e c t I r e c e i v e d a s s i s t a n c e from many p e o p l e . N o t a b l e among them was D r . L . M . L a v k u l i c h , whose p o s i t i v e , c o n s i d e r a t e approach i s something I s h a l l t r y t o emula te . I am a l s o i n d e b t e d t o D r . A . A . Bomke f o r h i s a d v i c e and encouragement, t o D r . J . V . T h i r g o o d who go t me i n v o l v e d on t h i s p r o j e c t , and t o D r . H . S . S c h r e i e r f o r g e t t i n g me s t a r t e d on m i c r o c o m p u t e r s . Thanks i s a l s o e x p r e s s e d t o the v a r i o u s p e r s o n n e l o f AMAX o f Canada L t d . who p r o v i d e d t e c h n i c a l h e l p , and t o the company i t s e l f f o r the use o f i t s f a c i l i t i e s and f o r i t s f i n a n c i a l h e l p . F i n a n c i a l a i d from the N a t i o n a l R e s e a r c h C o u n c i l o f Canada and the B . C . S c i e n c e C o u n c i l i s g r a t e f u l l y acknowledged. I would a l s o l i k e t o thank E v e l i n e W o l t e r s o n f o r h e r s u b t a n t i a l h e l p i n t h e l a b o r a t o r y and w i t h t h e computer , and t o a l l t h e o t h e r members o f the department who h e l p e d me over t h e y e a r s . L a s t and perhaps most i m p o r t a n t l y , I would l i k e t o thank my f r i e n d s Chuck Bulmer , J i m and Susan J a r d i n e , C h r i s t i n a M a c n e i l , T r e v o r M u r r i e , and J u l i e R o b i n s o n f o r t h e i r c o n s i d e r a b l e c o n t r i b u t i o n s and encouragement. 1 1 . INTRODUCTION 1. G l o s s a r y O r e : Rock t h a t c o n t a i n s s u f f i c i e n t amounts o f t h e e c o n o m i c a l l y v a l u a b l e e lements t o w a r r a n t i t s e x t r a c t i o n . Wasterock: Rock t h a t does not c o n t a i n s u f f i c i e n t amounts o f t h e e c o n o m i c a l l y v a l u a b l e e lements t o w a r r a n t i t s e x t r a c t i o n , but which has t o be removed t o a l l o w a c c e s s t o t h e o r e . The was terock i s b l a s t e d i n t o s m a l l e r p a r t i c l e s t o a l l o w i t s removal by t r u c k and s h o v e l . T a i l i n g s : M a t e r i a l r e m a i n i n g a f t e r the e c o n o m i c a l l y v a l u a b l e e lements a r e removed from t h e o r e . To remove the v a l u a b l e e l ements , i n t h i s case Mo, the b l a s t e d r o c k goes t h r o u g h s e v e r a l s t e p s o f c r u s h i n g and Mo e x t r a c t i o n . The r e s u l t i n g r e s i d u e o r t a i l i n g s u s u a l l y c o n s i s t s o f a s l u r r y o f sand a n d / o r s i l t - s i z e d p a r t i c l e s i n water . O v e r b u r d e n : A t c o a l mines , overburden i n c l u d e s b o t h bedrock and n a t u r a l l y u n c o n s o l i d a t e d s u r f i c i a l m a t e r i a l s on top o f t h e c o a l seams. A t meta l mines , the t erm overburden u s u a l l y o n l y r e f e r s t o n a t u r a l l y u n c o n s o l i d a t e d s u r f i c i a l m a t e r i a l s . The meta l mine d e f i n i t i o n was used i n t h i s t h e s i s . 2 S o i l : The r o o t i n g medium, p r e s e n t o r p o t e n t i a l . Man-made media on the s u r f a c e c o n t a i n i n g s o i l - s i z e d p a r t i c l e s and which can support p l a n t growth are o f t e n c a l l e d p r o t o - s o i l s . In t h i s study the term s o i l was used f o r both n a t u r a l and man-made r o o t i n g media. S o i l - s i z e d : P a r t i c l e s l e s s than 2 mm i n diameter. Incompetent Rock: A r e l a t i v e l y r a r e i n t r u s i v e r o c k type, i d e n t i f i e d by i t s l a c k o f co h e s i o n . Found i n t h e c e n t e r o f t h e p i t . P o t a s s i c Rock: The most common rock type found i n t h e waste a t K i t s a u l t , i t i s a c o h e s i v e i n t r u s i v e r ock, predominantly composed of qua r t z and K f e l d s p a r p h e n o c r y s t s . 3 2. O v e r v i ew o f t h e P r o j e c t The s u b j e c t o f t h i s s t u d y was t h e l a n d r e c l a m a t i o n o f mine w a s t e s a t t h e K i t s a u l t m i n e s i t e . The p r o j e c t had two components. The o b j e c t i v e i n t h e f i r s t , " P l a n t and S o i l F a c t o r s L i m i t i n g t h e Rate o f R e c l a m a t i o n " , was t o i d e n t i f y t h e f a c t o r s i m p e d i n g p l a n t growth. To meet t h i s o b j e c t i v e , p l a n t g r o w t h and s o i l p r o p e r t i e s i n f i e l d t r i a l s e s t a b l i s h e d between 1970 and 1982 were s t u d i e d , n a t u r a l p l a n t i n v a s i o n and t h e a s s o c i a t e d changes i n s o i l p r o p e r t i e s were measured, and e v a l u a t e d t e c h n i q u e s f o r e s t a b l i s h i n g p l a n t g r o w t h on t h e c o a r s e dump s l o p e s were e v a l u a t e d . C o n c l u s i o n s were r e a c h e d as t o t h e ma j o r l i m i t a t i o n s o f t h e s o i l and p l a n t r e s o u r c e s w i t h r e g a r d s t o f o r e s t development. T r a n s f o r m a t i o n s o c c u r r i n g on t h e w a s t e r o c k dumps were compared w i t h t h e changes o b s e r v e d i n p r i m a r y s u c c e s s i o n on r e c e n t l y d e g l a c i a t e d s i t e s i n S.E. A l a s k a , an a r e a w i t h s i m i l a r e n v i r o n m e n t a l c o n d i t i o n s , and s u g g e s t i o n s were made as t o t h e b e s t manner f o r a c c e l e r a t i n g t h e n a t u r a l p r o c e s s e s . The most i n h o s p i t a b l e e n v i r o n m e n t f o r p l a n t g r o w t h o c c u r r e d on t h e b o u l d e r c o v e r e d dump s l o p e s . Methods f o r a m e l i o r a t i n g t h e s l o p e s were t e s t e d i n f i e l d t r i a l s . The second p a r t o f t h e s t u d y , an o u t g r o w t h o f t h e s l o p e t r i a l s , examined whether a v e n e e r o f i n c o m p e t e n t w a s t e r o c k c o u l d be us e d on t h e a n g l e o f r e p o s e s l o p e s . The e x p o s u r e o f b l a s t e d r o c k p a r t i c l e s t o ambient l e v e l s o f p r e s s u r e and t e m p e r a t u r e , a i r and w a t e r , and o r g a n i c i n p u t s a s s o c i a t e d w i t h p l a n t growth i s l i k e l y t o r e s u l t i n s i g n i f i c a n t changes 4 i n t h e i r make-up. W i t h f u r t h e r s o i l development and p l a n t g r o w t h , f a c t o r s p r o m o t i n g w e a t h e r i n g w i l l be i n t e n s i f i e d . The o b j e c t i v e o f t h e second p a r t o f t h e s t u d y was t o p r e d i c t what e f f e c t s t h e s e changes w i l l have on t h e p r o p e r t i e s o f t h e i n c o m p e t e n t w a s t e r o c k , i n o r d e r t o d e t e r m i n e how c o m p a t i b l e i t w i l l be w i t h t h e g o a l s o f r e c l a m a t i o n : t h e development o f a w i l d e r n e s s f o r e s t w i t h p r o t e c t e d w a t e r s h e d v a l u e s . The f i r s t s t e p t o u n d e r s t a n d i n g how t h e i n c o m p e t e n t .• w a s t e r o c k w i l l p e r f o r m was t o d e t e r m i n e i t s c o m p o s i t i o n . A n a l y s e s were c a r r i e d o u t t o c h a r a c t e r i z e t h e i n c o m p e t e n t w a s t e r o c k and show how i t d i f f e r e d from t h e more common r o c k t y p e s f o u n d i n t h e waste. I n f o r m a t i o n on p e d o g e n e s i s and w e a t h e r i n g a t t h e m i n e s i t e was g a t h e r e d from two s o u r c e s : w a s t e r o c k on t h e abandoned dumps and two n a t u r a l s o i l p r o f i l e s w i t h i n t h e p r o p o s e d p i t l i m i t s . The changes i n t h e w a s t e r o c k on t h e abandoned dumps p r o v i d e d i n f o r m a t i o n about t h e t y p e o f changes t h a t w i l l o c c u r w i t h i n t e n y e a r s . The n a t u r a l s o i l p r o f i l e s showed t h e e f f e c t s o f much l o n g e r p e r i o d s o f p e d o g e n e s i s , and t h e c o n d i t i o n s under w h i c h p e d o g e n i c changes o c c u r r e d . I t was i m p o s s i b l e t o examine s o i l p r o f i l e s d e v e l o p e d from i n c o m p e t e n t r o c k , s i n c e a r e a s where t h e i n c o m p e t e n t r o c k may have been exposed had a l r e a d y been mined. A l t h o u g h t h e p a r e n t m a t e r i a l s o f t h e n a t u r a l s o i l s and much o f t h e weathered w a s t e r o c k were n o t composed o f i n c o m p e t e n t r o c k , t h e y had a g r e a t number o f p r o p e r t i e s i n common w i t h i t . Thus i n f o r m a t i o n about how t h e y a l t e r e d c o u l d be used t o p r e d i c t c e r t a i n a s p e c t s o f in c o m p e t e n t w a s t e r o c k a l t e r a t i o n . I n o r d e r t o more a c c u r a t e l y a s s e s s t h e e f f e c t s o f w e a t h e r i n g on p r o p e r t i e s such as p a r t i c l e s i z e , w e a t h e r i n g o f t h e i n c o m p e t e n t w a s t e r o c k was s i m u l a t e d i n t h e l a b o r a t o r y . The t e c h n i q u e u s e d was a s o x h l e t d i s t i l l a t i o n w i t h a c e t i c a c i d . W h i l e t h e d a t a c o l l e c t e d and t h e e n v i r o n m e n t a l e f f e c t s c o n s i d e r e d a r e t h o s e o f t h e K i t s a u l t m i n e s i t e , t h e w a s t e r o c k s o i l p r o p e r t i e s , g e o l o g y , and dump c o n s t r u c t i o n a r e s i m i l a r t o t h o s e o f many h a r d r o c k mines i n B.C. and e l s e w h e r e i n t h e w o r l d . Many mines l a c k s u f f i c i e n t r e s e r v e s o f u n c o n s o l i d a t e d s o i l - l i k e m a t e r i a l s t o use as s u r f a c e g r o w t h media, e i t h e r because much o f t h e mine had been d e v e l o p e d b e f o r e t h e n e c e s s i t y o f s o i l c o n s e r v a t i o n was r e a l i z e d o r because t h e q u a l i t y and q u a n t i t y o f t h e u n c o n s o l i d a t e d s o i l -l i k e m a t e r i a l i s low i n s t e e p , g l a c i a t e d m o u n t a i n l a n d s c a p e s . Thus, a l t h o u g h t h e c o n c l u s i o n s r e a c h e d v i s a v i s i d e n t i f y i n g and u s i n g d i f f e r e n t w a s t e r o c k t y p e s s p e c i f i c a l l y r e f e r t o K i t s a u l t , t h e methodology i s g e n e r a l l y a p p l i c a b l e and t h e p o t e n t i a l b e n e f i t s o f o p t i m a l l y p l a c i n g d i f f e r e n t r o c k t y p e s have w i d e r s i g n i f i c a n c e . 6 3. D e s c r i p t i o n o f t h e Study S i t e 3.1 L o c a t i o n The K i t s a u l t molybdenum mine i s l o c a t e d a t l a t i t u d e 55° 25' n o r t h and l o n g i t u d e 129° 25» west, a p p r o x i m a t e l y 150 km n o r t h e a s t o f P r i n c e R u p e r t , B r i t i s h C o l u m b i a . The p r o p e r t y has two components, t h e t o w n s i t e and t h e m i l l - m i n e complex. The t o w n s i t e was b u i l t a t s e a - l e v e l , n e a r t h e head o f A l i c e Arm. The m i l l - m i n e complex i s s i t u a t e d 6 km s o u t h o f t h e - • t o w n s i t e , a t an e l e v a t i o n o f 600 t o 900 m. 3.2 Geology The K i t s a u l t o r e body i s a p o r p h y r y Cu-Mo t y p e o f d e p o s i t ( E c k s t r a n d , 1984). Ore d e p o s i t s o f t h i s t y p e a c c o u n t f o r 60% o f t h e w o r l d ' s c o p p e r r e s e r v e s and 99% o f t h e w o r l d ' s molybdenum r e s e r v e s , and a l a r g e number o f companies a r e m i n i n g t h e s e d e p o s i t s b o t h i n Canada and ab r o a d . I n B.C. su c h mines i n c l u d e Endako, L o r n e x , Bethlehem, Brenda, G r a n i s l e , I s l a n d Copper, S i m i l k a m e e n , and A f t o n ( E c k s t r a n d , 1984). The g e o l o g y o f Cu-Mo p o r p h y r y d e p o s i t s has r e c e i v e d much a t t e n t i o n (Beane, 1982; C a r t e r , 1974; S o r e g a r o l i & S u t h e r l a n d Brown, 1976; Rose & B u r t , 1979). Most o f t h e p o r p h y r y Cu-Mo d e p o s i t s found i n w e s t - c e n t r a l B.C. a r e a s s o c i a t e d w i t h s m a l l s t o c k s , w h i c h i n t r u d e v o l c a n i c and s e d i m e n t a r y r o c k s ( C a r t e r , 1974). These i n t r u s i v e s t o c k s g e n e r a l l y do n o t exceed a k i l o m e t r e i n d i a m e t e r , a r e 7 commonly m u l t i p l e , and range i n c o m p o s i t i o n from q u a r t z d i o r i t e t o g r a n i t e . A c c o r d i n g t o G r i f f i t h s and Godwin (19 8 3 ) , Cu and Mo a r e d e r i v e d from t h e p r i m a r y g r a n i t o i d m e l t and t h e Cu:Mo r a t i o r e f l e c t s t h e c o m p o s i t i o n o f t h a t m e l t . O t h e r t r a c e e l e m e n t s , Pb, Zn, Au, and Ag, o c c u r i n v e i n s p e r i p h e r a l t o t h e p o r p h y r y i n t r u s i o n s , and t h e m e t a l c o n t e n t o f t h e s e v e i n s i s c o n t r o l l e d by t h e l i t h o l o g y o f t h e w a l l r o c k s . Of t h e p o r p h y r y Cu-Mo d e p o s i t s l o c a t e d i n west-c e n t r a l B.C., K i t s a u l t had t h e most g r a n i t i c m i n e r a l o g y ( C a r t e r , 1974; S o r e g a r o l i & S u t h e r l a n d Brown, 1976). Of t h e o t h e r o p e r a t i n g mines, t h e l i t h o l o g y o f t h e r o c k a t Endako was t h e most s i m i l a r t o K i t s a u l t . Molybdenum o r e a t K i t s a u l t i s a s s o c i a t e d w i t h t h e s e r i e s o f i g n e o u s s t o c k s w h i c h make up t h e Lime Creek I n t r u s i v e Complex. The h o s t r o c k s t h r o u g h w h i c h t h e i g n e o u s r o c k i n t r u d e d a r e i n t e r b e d d e d a r g i l l i t e s and graywackes o f t h e Bowser Lake Group. These were t h e r m a l l y metamorphosed i n t o h o r n f e l s . The i n t r u s i v e s s t o c k s v a r y i n c o m p o s i t i o n from q u a r t z d i o r i t e t o q u a r t z m o n z o n i t e p o r p h y r y , w i t h t h e l a t t e r making up most o f what has been mined t o d a t e . Much o f t h e i g n e o u s r o c k w i t h i n t h e p i t was h y d r o t h e r m a l l y a l t e r e d . S i l i c i c , p o t a s s i c , p h y l l i c , a r g i l l i c , and p r o p y l i t i c a l t e r a t i o n t y p e s have a l l been i d e n t i f i e d , however most o f t h e ig n e o u s o r e and w a s t e r o c k i s t h e p o t a s s i c a l t e r a t i o n t y p e . I n t h e p o t a s s i c r o c k t h e pre d o m i n a n t form o f h y d r o t h e r m a l a l t e r a t i o n was t h e s e l e c t i v e r e p l a c e m e n t o f p l a g i o c l a s e by K f e l d s p a r 8 ( S t e i n i n g e r , 1985) . In the f i e l d , the p o t a s s i c r o c k was i d e n t i f i e d by the predominance o f c o a r s e g r a i n s o f K f e l d s p a r and q u a r t z . A n o t h e r l e s s common, b u t d i s t i n c t igneous r o c k t y p e was i d e n t i f i e d by i t s incompetent n a t u r e . 3.3 C l i m a t e The m i n e s i t e has a c o o l , humid m a r i t i m e c l i m a t e , a l t h o u g h i t i s not u n u s u a l t o have 3 o r 4 weeks w i t h o u t p r e c i p i t a t i o n i n t h e summer. D u r i n g w i n t e r t h e m i c r o c l i m a t e a t t h e s o i l s u r f a c e i s moderated by the deep snow c o v e r . Under a s i m i l a r deep snow c o v e r , i n a s l i g h t l y h a r s h e r s u b a l p i n e environment i n S.W. B r i t i s h C o l u m b i a , Brooke e t a l (1970) found t h a t the s u r f a c e s o i l t e m p e r a t u r e r a r e l y dropped below 0 ° C . 3.4 Topography and Dra inage The m i n e s i t e i s l o c a t e d i n rugged , mountainous t e r r a i n . W i t h i n a 10 km a r e a , the e l e v a t i o n v a r i e s from sea l e v e l t o 1800 m. The m i n e s i t e i s d r a i n e d by t h e d e e p l y i n c i s e d c h a n n e l s o f the P a t s y and Lime C r e e k s . As a l l t h e s o i l s are c o a r s e t e x t u r e d , the r a t e o f d r a i n a g e l a r g e l y depends on the t o p o g r a p h y . 3 .5 V e g e t a t i o n Changes i n s p e c i e s c o m p o s i t i o n o f the v e g e t a t i v e c o v e r i n t h e K i t s a u l t a r e a r e s u l t from changes i n e l e v a t i o n , and from the t r a n s i t i o n from a m a r i t i m e t o a more c o n t i n e n t a l 9 c l i m a t e . A c c o r d i n g t o H a e u s s l e r e t a l . (1974), the m i n e s i t e i s l o c a t e d a t t h e t r a n s i t i o n between t h e h i g h e l e v a t i o n v a r i a n t o f t h e N o r t h e r n D r i e r M a r i t i m e Subzone o f t h e C o a s t a l Western Hemlock Zone and t h e S u b a l p i n e Mounta in Hemlock Zone, and c l o s e t o the t r a n s i t i o n from S u b a l p i n e M o u n t a i n Hemlock t o the Englemann Spruce - S u b a l p i n e F i r zones . The d i s t r i b u t i o n o f v e g e t a t i o n and s o i l t y p e s i s c l o s e l y l i n k e d t o the t e r r a i n ( G i l l , 1978) . Where the topography i s r e l a t i v e l y f l a t and the d r a i n a g e i s p o o r , a sedge (Carex s p e c i e s ) - m o u n t a i n hemlock (Tsuga m e r t e n s i a n a (Bong.) C a r r ) p a r k l a n d ecosystem forms. On w e l l d r a i n e d s l o p e s t h e r e i s an overmature mixed wes tern (Tsuga  h e t e r o p h v l l a ( R a f . ) S a r g . ) and mountain hemlock f o r e s t , w i t h a m a b a l i s f i r (Abies amaba l i s (Dougl . ) Forbes) common i n the u n d e r s t o r y . On w e l l d r a i n e d a r e a s , t h e most common shrubs a r e v a r i o u s V a c c i n i u m s p e c i e s and f a l s e a z a l e a ( M e n z i e s i a  f e r r u g i n e a Smith) ( G i l l , 1978) . A d j a c e n t t o the mine , a dense c o v e r o f S i t k a a l d e r (Alnus s i n u a t a (Reg.) R y d b . ) , w i t h a s c a t t e r e d component o f b l a c k cottonwood (Populus t r i c h o c a r p a T o r r . and Gray) and w i l l o w s p e c i e s ( S a l i x s p p . ) a r e growing on ground d i s t u r b e d by mine e x p l o r a t i o n and on r e c e n t l y a c t i v e c o l l u v i u m . Where a l i t t e r l a y e r has deve loped beneath the a l d e r , S i t k a spruce ( P i c e a s i t c h e n s i s (Bong.) C a r r . and hemlock (Tsuga s p p . ) s e e d l i n g s a r e growing v i g o r o u s l y . A t the e l e v a t i o n o f the m i n e s i t e , w i l l o w i s the most p r o l i f i c s p e c i e s on a c t i v e 10 a l l u v i u m , w h i l e a t lower e l e v a t i o n s (approx . 300-400 m), 50 km n o r t h e a s t i n the Nass V a l l e y , l a r g e s t a n d s o f a p p r o x i m a t e l y 20 y e a r o l d l o d g e p o l e p i n e (P inus c o n t o r t a D o u g l . ) grow on r e c e n t l y burned a r e a s . Red a l d e r (Almas r u b r a B o n g . ) , a v e r y v i g o r o u s c o l o n i z e r o f d i s t u r b e d areas a t sea l e v e l ( e . g . , the t o w n s i t e ) , i s not found above about 200 metres e l e v a t i o n . 3 .6 S u r f i c i a l M a t e r i a l s and S o i l s A c c o r d i n g t o t h e B . C . t e r r a i n c l a s s i f i c a t i o n ( E . L . U . C . , 1976) , t h e s u r f a c e c o v e r a d j a c e n t t o the mine i s l a r g e l y c o l l u v i u m w i t h l e s s e r amounts o f bedrock and o r g a n i c m a t e r i a l s , and a few areas o f m o r a i n a l and f l u v i a l m a t e r i a l . In most cases t h e u n c o n s o l i d a t e d m a t e r i a l s were mapped as v e n e e r s (10 cm t o 1 m deep) o r b l a n k e t s ( t h i c k e r t h a n 1 m, b u t not t h i c k enough t o mask u n d e r l y i n g minor t o p o g r a p h i c i r r e g u l a r i t i e s i n the b e d r o c k ) . Due t o t h e c o o l , humid c l i m a t e , p l a n t d e b r i s decomposes v e r y s l o w l y , and a l l b u t t h e most p r e c i p i t o u s s l o p e s a r e c o v e r e d by a t l e a s t 10 cm o f p l a n t l i t t e r . C o n s i d e r a b l y deeper o r g a n i c d e p o s i t s have accumula ted i n w a t e r l o g g e d h o l l o w s and on g e n t l e s l o p e s . No t h o r o u g h s o i l s u r v e y s have been c a r r i e d out i n the immediate v i c i n i t y o f the m i n e s i t e . In a b i o p h y s i c a l s tudy a d j a c e n t t o t h e mine , G i l l (1978) found O r t h i c H u m o - F e r r i c P o d z o l s and F o l i s o l s on the w e l l d r a i n e d s l o p e s . On areas w i t h impeded d r a i n a g e he found G l e y s o l s and f i b r i c o r mes ic o r g a n i c s o i l s . R e g o s o l s and B r u n i s o l s o c c u r r e d on more 11 r e c e n t l y d i s t u r b e d s i t e s . M i n e r a l s o i l s g e n e r a l l y had a h i g h c o a r s e fragment c o n t e n t , w i t h t e x t u r e s r a n g i n g from loam t o s a n d . 3 .7 Mine H i s t o r y and M i n i n g Method The mine was i n i t i a l l y d e v e l o p e d by B r i t i s h Columbia Molybdenum L i m i t e d who o p e r a t e d i t from 1967 t o 1972. In 1972, f a l l i n g molybdenum p r i c e s caused t h e mine t o c l o s e . S u b s e q u e n t l y i t was bought by Amax o f Canada L t d . , and was reopened i n 1980. In 1982, f a l l i n g molybdenum p r i c e s a g a i n l e d t o t h e c l o s u r e o f the mine , and a l t h o u g h i t has no t been abandoned, no m i n i n g has o c c u r r e d s i n c e t h a t d a t e . The f u t u r e v i a b i l i t y o f the mine w i l l depend upon t h e molybdenum m a r k e t . The mine was an open p i t t r u c k and s h o v e l o p e r a t i o n . The l a r g e s t t e r r e s t r i a l d i s t u r b a n c e s a r e t h e open p i t and t h e was terock dumps. I n i t i a l l y roads and b u i l d i n g s formed a s i g n i f i c a n t p r o p o r t i o n o f the d i s t u r b e d a r e a s , b u t as m i n i n g p r o c e e d e d , t h e i r s i z e r e l a t i v e t o t h e was terock dumps d e c r e a s e d . F o r use i n r e c l a m a t i o n , AMAX s t r i p p e d s o i l - l i k e o v e r b u r d e n p r i o r t o mine e x p a n s i o n . S o i l m a t e r i a l was no t c o n s e r v e d by t h e p r e d e c e s s o r company, BC Molybdenum. Due t o t h e s t eepness o f the t e r r a i n , w a s t e r o c k was s t o r e d i n t e r r a c e d dumps. The t e c h n i q u e used t o b u i l d a t e r r a c e was f o r a b u l l d o z e r t o push p i l e s o f b l a s t e d r o c k up t o and o v e r the a d v a n c i n g t e r r a c e f a c e . T h i s r e s u l t e d i n a g r a v i m e t r i c s e p a r a t i o n o f the r o c k , w i t h s tones and b o u l d e r s 12 b o u n c i n g down the s l o p e , w h i l e f i n e s were r e t a i n e d i n c r e v i c e s a t o r near the t o p . A t p r e s e n t , except f o r t h e bench a t t h e t o p , most o f the dump c o n t a i n s l i t t l e o r no f i n e s . A f o u n d a t i o n o f b o u l d e r s i s i m p o r t a n t f o r dump s t a b i l i t y as t h e l a r g e p o r e s between b o u l d e r s can conduct l a r g e volumes o f water , t h u s p r e v e n t i n g t h e b u i l d up o f h y d r a u l i c p r e s s u r e s t h a t c o u l d cause mass w a s t i n g . 3 .8 P r e v i o u s R e c l a m a t i o n and the P r e s e n t R e c l a m a t i o n O b j e c t i v e When r e q u e s t i n g an e x t e n s i o n o f i t s m i n i n g p e r m i t i n 1970, B . C . Molybdenum proposed t o t u r n t h e p i t i n t o a l a k e and a l l o w t h e waste r o c k dumps t o r e v e g e t a t e n a t u r a l l y ( P r i c e , 1982) . The company's a s s u r a n c e t h a t n a t u r a l r e v e g e t a t i o n would o c c u r was based on: (1) t h e humid c l i m a t e and l u s h v i g o r o u s n a t u r a l v e g e t a t i o n , and (2) the e v i d e n c e o f n a t u r a l r e f o r e s t a t i o n t h a t had a l r e a d y o c c u r r e d a t t h e o l d Anyox mine s i t e . Anyox, a l a r g e s m e l t e r and underground mine abandoned i n t h e 1920's , i s l o c a t e d a t the mouth o f A l i c e Arm. In case n a t u r a l p l a n t i n v a s i o n f a i l e d , B . C . Molybdenum agreed t o s e t up f i e l d t r i a l s t o d e v e l o p a r t i f i c i a l r e c l a m a t i o n methods. S e v e r a l t r i a l s were e s t a b l i s h e d . The f i e l d t r i a l s were v i s u a l l y m o n i t o r e d each y e a r from 1970 t o 1978 ( P r i c e , 1982) . When t h e mine r e - o p e n e d i n 1980 more r i g o r o u s r u l e s f o r r e c l a m a t i o n were i n p l a c e . In o r d e r t o ge t a M i n i n g P e r m i t AMAX had t o submit an a c c e p t a b l e r e c l a m a t i o n p l a n t o the 13 p r o v i n c i a l government. A m i n i n g p e r m i t was g i v e n f o r the r e - o p e n i n g o f the mine on the b a s i s t h a t a f t e r m i n i n g , an e r o s i o n - p r e v e n t i n g f o r e s t c o v e r would be grown on a l l the d i s t u r b e d a r e a s , except the open p i t . I t i s t o be t u r n e d i n t o a l a k e . The e r o s i o n - p r e v e n t i n g end l a n d use was j u s t i f i e d on t h e b a s i s t h a t t h e p r e - m i n i n g env ironment was an overmature f o r e s t , w i t h no p r o d u c t i v e s o i l s , no t i m p o r t a n t w i l d l i f e h a b i t a t , and no a c c e s s f o r r e c r e a t i o n (AMAX, 1980) . A t p r e s e n t t h e r e i s no t ime l i m i t f o r r e c l a m a t i o n . 14 I I . PLANT AND SOIL FACTORS THAT COULD LIMIT THE RATE OF RECLAMATION 1. OBJECTIVE The o b j e c t i v e o f t h e f i r s t p a r t o f t h e t h e s i s was t o i d e n t i f y t h e p l a n t and s o i l f a c t o r s l i m i t i n g t h e r a t e o f r e c l a m a t i o n on t h e t e r r a c e d w a s t e r o c k dumps. T h i s s t u d y f o c u s e d oh t h e t e r r a c e d w a s t e r o c k dumps f o r two r e a s o n s . F i r s t , a c c o r d i n g t o t h e r e c l a m a t i o n p l a n , when t h e mine i s c o m p l e t e d , dumps o f t h i s t y p e w i l l a c c o u n t f o r most o f t h e a r e a d i s t u r b e d . The second r e a s o n i s t h a t o b s e r v a t i o n s o f n a t u r a l p l a n t i n v a s i o n b o t h a t t h i s and o t h e r mines ( L a v k u l i c h e t a l . , 1976) s u g g e s t t h a t t h e l a r g e dumps w i l l be t h e most d i f f i c u l t a r e a s t o r e v e g e t a t e . O t h e r f a c t o r s , s u c h as c l i m a t e , t o p o g r a p h y , t i m e and f i n a n c i a l c o n s i d e r a t i o n s , a r e p o t e n t i a l l y l i m i t i n g . However a t K i t s a u l t , t h e s e f a c t o r s a r e e i t h e r n o t l i k e l y t o pose p r o b l e m s o r t h e y w i l l be t a k e n i n t o a c c o u n t i n t h e s e l e c t i o n o f s o i l and p l a n t m a t e r i a l s and methods. F o r example, w i t h s u c h a heavy snow f a l l , a v a l a n c h i n g c o u l d be a p r o b l e m on l o n g , s t e e p s l o p e s . However, t h e mine p l a n s t o make t h e dump s l o p e s q u i t e s h o r t (AMAX, 1980). 15 2. LITERATURE REVIEW 2 .1 P r o p e r t i e s o f Wasterock P o r p h y r y Cu-Mo mines a r e commonly r e f e r r e d t o as h a r d r o c k mines , because the r o c k mined i s g e n e r a l l y i n d u r a t e and competent . As a r e s u l t the was terock from p o r p h y r y Cu-Mo mines c o n t a i n a much s m a l l e r p r o p o r t i o n o f f i n e s t h a n was terock d e r i v e d from c o a l o v e r b u r d e n . On average o n l y 16 t o 25% o f p a r t i c l e s i n was terock on t e r r a c e d dump benches a t p o r p h y r y Cu-Mo mines i n B . C . were < 2 mm (Murray , 1977) , w h i l e t h e a s s o c i a t e d s l o p e s were a lmost d e v o i d o f f i n e s ( L a v k u l i c h e t a l . , 1976) . Most o f t h e s o i l - s i z e d p a r t i c l e s (60 t o 71%) were s a n d - s i z e d , and thus the w a s t e r o c k s had a low a v a i l a b l e water r e t e n t i o n (6 t o 11%) and a low CEC (7 t o 15 m e q / l O O g ) . The h i g h b u l k d e n s i t y (1 .6 t o 1.8 g/cm3) o f w a s t e r o c k was a t t r i b u t e d t o the h i g h c o a r s e fragment c o n t e n t . The K i t s a u l t r o c k and was terock c o n t a i n e d more C a , K, and S t h a n the was terock from o t h e r p o r p h y r y Cu-Mo mines ( S t e i n i n g e r , 1985; AMAX, 1980) . H i g h e r Ca v a l u e s may be a t t r i b u t e d t o the p r e s e n c e o f e i t h e r p l a g i o c l a s e o r c a l c i t e . H i g h e r t o t a l K v a l u e s r e s u l t e d i n h i g h e r a v a i l a b l e K l e v e l s (AMAX, 1980) . H i g h e r S v a l u e s i n the K i t s a u l t was terock sample sugges t t h a t a c i d g e n e r a t i o n may o c c u r . However s t u d i e s o f p o t e n t i a l a c i d p r o d u c t i o n on a wide range o f d i f f e r e n t r o c k t y p e s from K i t s a u l t c o n c l u d e d t h a t t h e h i g h 16 a c i d - c o n s u m i n g a b i l i t y w i l l p r e v e n t t h e was terock from becoming a c i d i c ( B . C . R e s e a r c h , 1981). By d e f i n i t i o n the t r a c e element c o m p o s i t i o n o f an ore body i s anomalous. A t K i t s a u l t , A s , C d , C u , Mo, Pb , and Zn l e v e l s i n t h e r o c k were a l l s i g n i f i c a n t l y h i g h e r t h a n the t y p i c a l c o m p o s i t i o n o f a g r a n i t e r o c k (AMAX, 1980) . A l l t r a c e e lements except Cu were h i g h e r t h a n t h e upper l i m i t s a l l o w e d i n A l b e r t a a g r i c u l t u r a l s o i l s ( B a l l a r d , 1980) . In t h e unweathered w a s t e r o c k , a v a i l a b l e l e v e l s o f t r a c e e lements a r e not l i k e l y t o be h i g h , but w i l l i n c r e a s e as w e a t h e r i n g p r o c e e d s . The a v a i l a b i l i t y o f d i f f e r e n t e lements depends on t h e o r i g i n a l c o m p o s i t i o n o f the r o c k and i t s s u s c e p t i b i l i t y t o w e a t h e r i n g . A l l t h e was terock t y p e s c o l l e c t e d from p o r p h y r y Cu-Mo mines by Murray (1977) were unweathered, and t h u s had h i g h pH v a l u e s r a n g i n g from 7.1 t o 8 . 3 . The range f o r pH w i t h C a C l 2 was 6.6 t o 7 . 5 , 0.7 t o 1.0 u n i t l ower t h a n t h a t i n w a t e r . L e v e l s o f ammonium a c e t a t e e x t r a c t a b l e Ca were h i g h (0 .1 t o 1.0 %), i n d i c a t i n g t h a t t h e was terock c o n t a i n e d c a l c i t e . C a l c i t e w i l l a l s o c o n t r i b u t e t o t h e h i g h p H . The low a v a i l a b l e P l e v e l s (0 t o 8 ppm) r e s u l t e d from a l a c k o f adsorbed P i n unweathered m a t e r i a l s . A v a i l a b l e P l e v e l s s h o u l d i n c r e a s e as w e a t h e r i n g proceeds ( B r a y , 1974) . R e s e a r c h e r s sampled f o l i a g e a t the bloom s t a g e from p l a n t s growing on mine wastes and on a d j a c e n t n a t u r a l s o i l s a t mines i n B . C . ( L a v k u l i c h e t a l . , 1976) . T r a c e e lements c o n c e n t r a t i o n s i n the f o l i a g e o f r e d f e scue grown on Endako 17 mine wastes were s i m i l a r t o the amounts found i n r e d f e scue grown on a d j a c e n t n a t u r a l s o i l s ( L a v k u l i c h e t a l . , 1976) . The c o n c e n t r a t i o n s o f Mo (42 t o 52 ppm) i n b o t h the mine wastes and a d j a c e n t n a t u r a l s o i l s were much h i g h e r t h a n the normal range o f 0.2 t o 3.0 ppm found i n s o i l s ( A r c h e r & Hodgson, 1987) . The Cu:Mo r a t i o o f 0.3 t o 0.4 was a l s o very-low. A c c o r d i n g t o A g r i c u l t u r e Canada d i e t a r y g u i d e l i n e s (1981), r a t i o s o f l e s s t h a n 3:1 Cu:Mo i n f o r a g e a r e hazardous f o r bee f c a t t l e . Other r e s e a r c h e r s have proposed t h a t Cu:Mo r a t i o s l e s s t h a n 2:1 i n d i c a t e p o t e n t i a l l y t o x i c f e e d ( M i l t i m o r e & Mason, 1971) . A l t h o u g h Mo was o n l y d e t e r m i n e d f o r f o l i a g e grown on t a i l i n g s , s i m i l a r r e s u l t s may be expec ted on w a s t e r o c k . I n greenhouse t r i a l s , o r c h a r d g r a s s grown on Endako w a s t e r o c k showed a d r a m a t i c response t o N and P f e r t i l i z e r , b u t no response t o any o t h e r n u t r i e n t s ( L a v k u l i c h e t a l . , 1976) . A l t h o u g h t i m o t h y (Phleum p r a t e n s e L . ) and r e d f e scue grown on n a t u r a l s o i l s c o n t a i n e d s u b s t a n t i a l l y more K t h a n i n d i v i d u a l s grown on mine wastes , a p p l y i n g K f e r t i l i z e r d i d no t i n c r e a s e e i t h e r f o l i a r K o r the y i e l d s . A p p l y i n g m i c r o n u t r i e n t s (B, C u , F e , Mn, Mo, and Zn) and t h e p r e s e n c e o f heavy m e t a l s a l s o d i d not appear t o a f f e c t p l a n t growth . 18 2.2 S u i t a b i l i t y o f Wasterock f o r Use as a S o i l P o o r p l a n t growth on w a s t e r o c k may be due t o a c o m b i n a t i o n o f f a c t o r s . V a r i o u s a u t h o r s (Bradshaw & Chadwick, 1980; Michaud, 1981; L y l e , 1986; W i l l i a m s & Schuman, 1987) have l i s t e d t h e w a s t e r o c k c h a r a c t e r i s t i c s t h a t l i m i t p l a n t growth and s u g g e s t e d d i f f e r e n t methods f o r i d e n t i f y i n g them. Sometimes d e l e t e r i o u s p r o p e r t i e s can be p r e d i c t e d from t h e c h a r a c t e r i s t i c s o f t h e p r e - w a s t e b e d r o c k . F o r example a c o a r s e g r a i n e d b e d r o c k i n d i c a t e s t h a t t h e w a ste w i l l have a c o a r s e t e x t u r e ( C a r r o l , 1970). However, d i f f e r e n c e s i n g e o l o g y , t h e g r e a t d i v e r s i t y i n e n v i r o n m e n t a l c o n d i t i o n s , and t h e l a c k o f r e s e a r c h a t o t h e r mines make p r e d i c t i o n s o f t h i s s o r t v e r y d i f f i c u l t . S e v e r a l a u t h o r s have d e v i s e d c r i t e r i a f o r e v a l u a t i n g t h e s u i t a b i l i t y o f d i s t u r b e d s o i l m a t e r i a l s as a r o o t i n g medium ( e . g . , S c h a f e r , 1979; U.S.D.A., 1979; A l b e r t a S o i l s A d v i s o r y Committee, 1981). A l l a r e from j u r i s d i c t i o n s where t h e p r e - m i n i n g s o i l c o v e r must be r e a p p l i e d and t h u s t h e c r i t e r i a a r e b ased on p r o p e r t i e s o f t h e p r e v i o u s s o i l c o v e r . The r a t i n g scheme most a p p l i c a b l e t o B.C. i s t h e one c r e a t e d f o r c o a l mines i n t h e E a s t e r n S l o p e s R e g i o n o f A l b e r t a (A.S.A.C., 1981). The E a s t e r n S l o p e s R e g i o n i s f o r e s t e d and m o untainous, s i m i l i a r t o most o f B.C., and as t h e aim o f mine r e c l a m a t i o n i n B.C. i s u s u a l l y t o r e t u r n t h e r o o t i n g medium t o i t s p r e v i o u s p r o d u c t i v i t y , i t i s a p p r o p r i a t e t o e v a l u a t e mine wast e s w i t h c r i t e r i a used t o e v a l u a t e t h e p r e v i o u s s o i l c o v e r . A c c o r d i n g t o t h e A.S.A.C. (1981) 19 c r i t e r i a , t h e l o w e s t r a t i n g f o r a p r o p e r t y d e t e r m i n e s t h e o v e r a l l r a t i n g o f a s o i l . Based on most o f t h e i r p r o p e r t i e s , t h e p o r p h y r y Cu-Mo w a s t e r o c k t y p e s (Murray, 1977) would be r a t e d as e i t h e r good o r f a i r . A few m a t e r i a l s w i t h loamy sand t e x t u r e s would be r a t e d as p o o r . However a l l t h e w a s t e r o c k t y p e s would e a r n t h e r a t i n g o f u n s u i t a b l e o r p o o r on t h e b a s i s o f t h e i r h i g h c o a r s e f ragment c o n t e n t s . The n e g a t i v e a t t r i b u t e s o f r o c k f r a g m e n t s i n c l u d e a .. r e d u c t i o n i n r o o t i n g volume, a d e c l i n e i n t o t a l w a t e r -h o l d i n g c a p a c i t y , a r e d u c t i o n i n t o t a l s o i l n u t r i e n t s , and e l e v a t e d s u r f a c e t e m p e r a t u r e s (Munn e t a l . , 1987). The e l e v a t e d s u r f a c e t e m p e r a t u r e r e s u l t s from an i n c r e a s e i n t h e s u r f a c e r o c k c o v e r a g e . I n f o r e s t r y , s i t e q u a l i t y i s o f t e n s t r o n g l y c o r r e l a t e d w i t h a v a i l a b l e s o i l m o i s t u r e and e f f e c t i v e r o o t i n g volume. S t o n i n e s s may a l s o r e q u i r e t h e use o f d i f f e r e n t s i t e p r e p a r a t i o n equipment, i f s t o n e s damage equipment used t o p r e p a r e t h e s u r f a c e , and may p r e c l u d e o t h e r w i s e s u i t a b l e c u l t u r a l t e c h n i q u e s . T r e e p l a n t i n g i s a l s o more d i f f i c u l t i n r o c k y s u b s t r a t e s . " P o s i t i v e a t t r i b u t e s o f r o c k f r a g m e n t s i n s o i l s i n c l u d e r e d u c e d s u s c e p t i b i l i t y t o e r o s i o n and c o m p a c t i o n (Munn e t a l . , 1 9 87)." McCormack e t a l . (1984) s u g g e s t e d t h a t t h e s e l f - m u l c h i n g p r o p e r t i e s o f r o c k f r a g m e n t s on t h e s u r f a c e may c o n t r i b u t e t o v e g e t a t i v e e s t a b l i s h m e n t on s i t e s s u b j e c t t o e r o s i o n . E v a p o r a t i o n may a l s o be r e d u c e d because i n a r o c k y s o i l a g i v e n q u a n t i t y o f w a t e r w i l l p e n e t r a t e t o a 20 g r e a t e r d e p t h , due t o a r e d u c e d w a t e r s t o r a g e c a p a c i t y p e r u n i t volume n e a r t h e s u r f a c e ( B i r k e l a n d , 1984). D e s p i t e t h e s e p o s i t i v e a t t r i b u t e s , t h e r o c k fragment s u i t a b i l i t y c r i t e r i a r e q u i r e d by U.S. a u t h o r i t i e s were even s t r i c t e r t h a n t h e s e f o r t h e E a s t e r n S l o p e s R e g i o n o f A l b e r t a . A l e s s a r b i t r a r y scheme f o r e v a l u a t i n g mine w a s t e s i s t o c h e c k whether t h e y meet t h e m i n i m a l p h y s i c a l and c h e m i c a l c h a r a c t e r i s t i c s a s s o c i a t e d w i t h t h e growth o f t h e d e s i r e d . -v e g e t a t i o n c o v e r i n t h e s u r r o u n d i n g u n d i s t u r b e d e n v i r o n m e n t . T h i s a p p r o a c h has been used i n r e c o n s t r u c t i n g s o i l s on a r e a s d i s t u r b e d by t h e O i l Sands P r o j e c t i n A l b e r t a (Monenco C o n s u l t a n t s L t d . , 1983). One problem w i t h t h i s t e c h n i q u e i s t h a t i m p o r t a n t dynamic p r o c e s s e s and s u b t l e d i f f e r e n c e s a t t h e m i c r o s i t e l e v e l may be d i f f i c u l t t o measure. A n o t h e r p r o b l e m i s t h a t t h e m i n i m a l s o i l c h a r a c t e r i s t i c s a r e o f t e n p o o r l y d e f i n e d and t h i s t y p e o f i n f o r m a t i o n may be t i m e -consuming and c o s t l y t o c o l l e c t . 2.3 Mine R e c l a m a t i o n R e g u l a t i o n s I n B.C., mine r e c l a m a t i o n i s e n f o r c e d by p r o v i n c i a l l a w s r e g u l a t i n g t h e a l l o c a t i o n o f p e r m i t s and l i c e n s e s , w i t h o u t w h i c h m i n i n g i s i l l e g a l . To o b t a i n a M i n i n g P e r m i t , a mine must meet r e c l a m a t i o n r e q u i r e m e n t s s t i p u l a t e d i n s e c t i o n s 7, 8 and 9 o f t h e Mines A c t . However, t h e A c t does n o t e n f o r c e how t h e s t a n d a r d s must be met. The p h i l o s o p h y i s f o r " i n d u s t r y t o a c c o m p l i s h i t i n t h e way most s u i t e d t o them ( E r r i n g t o n , 1985)". A l i s t o f g u i d e l i n e s have been drawn up o u t l i n i n g c r i t e r i a f o r a c c e p t a b l e r e c l a m a t i o n i n a c c o r d a n c e w i t h t h e Mines A c t (Rogers, 1984). F o r p r o d u c t i v i t y , t h e g u i d e l i n e s s t a t e t h a t , "The l e v e l o f l a n d p r o d u c t i v i t y t o be a c h i e v e d on r e c l a i m e d l a n d s h a l l n o t be l e s s t h a n e x i s t e d p r i o r t o m i n i n g on an a v e r a g e p r o p e r t y b a s i s u n l e s s t h e p r o p o n e n t can produce adequate d o c u m e n t a t i o n t o s u p p o r t t h e i m p r a c t i c a l i t y o f t h i s l e v e l . Land s h a l l be v e g e t a t e d t o a s e l f s u s t a i n i n g s t a t e u s i n g a p p r o p r i a t e p l a n t s p e c i e s . " F o r s o i l s t h e g u i d e l i n e s s a y "A g r o w t h medium w h i c h w i l l s a t i s f y l a n d use and p r o d u c t i v i t y o b j e c t i v e s s h a l l be p l a c e d on t h e s u r f a c e . Where n e c e s s a r y , s u f f i c i e n t t o p s o i l o r o t h e r s u i t a b l e growth medium s h a l l be s a v e d f o r use i n r e c l a m a t i o n programs (Rogers, 1984)". 2.4 R e c l a m a t i o n R e s e a r c h A g r e a t v a r i e t y o f d i f f e r e n t forms o f l a n d d i s t u r b a n c e r e q u i r e r e c l a m a t i o n . I n t h e P a c i f i c N.W., most o f t h e r e s e a r c h has been c a r r i e d o u t on l a n d d i s t u r b e d by l o g g i n g ( e . g . , D r y n e s s , 1973), some o f w h i c h i s a p p l i c a b l e t o mine l a n d r e c l a m a t i o n . F o r example, agronomic seed mixes c r e a t e d f o r u se i n f o r e s t r y ( e . g . , C a r r , 1980) p r o v i d e a good s t a r t i n g p l a c e when l o o k i n g f o r t h e a p p r o p r i a t e agronomic s p e c i e s t o use i n mine l a n d r e c l a m a t i o n . However u n l i k e mine w a s t e s , w h i c h i n i t i a l l y a r e s t e r i l e , l a n d d i s t u r b e d by l o g g i n g and highway c o n s t r u c t i o n o f t e n a l r e a d y c o n t a i n s abundant p r o p a g u l e s and i s b i o l o g i c a l l y a c t i v e . 22 O t h e r d i f f e r e n c e s between l a n d d i s t u r b e d by l o g g i n g and mine w a s t e r o c k were i l l u s t r a t e d by E r r i n g t o n ' s (1975) s t u d y o f n a t u r a l p l a n t i n v a s i o n on abandoned l o g g i n g r o a d s and c o a l s p o i l s n e a r s e a l e v e l on t h e e a s t s i d e o f Vancouver I s l a n d . On l o g g i n g r o a d s , a l l i n v a d i n g p l a n t s p e c i e s i n c r e a s e d t h e i r c o v e r and f r e q u e n c y f o r t h e f i r s t 15 t o 20 y e a r s . A t t h i s s t a g e r e d a l d e r , a r e l a t i v e l y l a t e a r r i v a l , became dominant and i t s c l o s e d canopy shaded t h e o t h e r s p e c i e s . I n t h e e a r l y s t a g e s o f p l a n t i n v a s i o n t h e r e was.a good c o r r e l a t i o n between t h e i n v a d i n g p l a n t s p e c i e s and t h e s p e c i e s a l r e a d y g r o w i n g b e s i d e t h e r o a d . A s i m i l a r r e l a t i o n s h i p was o b s e r v e d a l o n g t h e edge o f c o a l s p o i l s . Compared w i t h t h e l o g g i n g r o a d s , p l a n t c o l o n i z a t i o n o f t h e c o a l s p o i l s was much s l o w e r . One f a c t o r t h a t c o n t r i b u t e d t o t h i s was t h e r e l a t i v e l y l a r g e s i z e o f t h e c o a l dump, w h i c h l i m i t e d t h e e f f e c t o f s u r r o u n d i n g v e g e t a t i o n b o t h as a s o u r c e o f p r o p a g u l e s and as a s o u r c e o f shade. L a c k of, shade, a l o n g w i t h t h e s o u t h - f a c i n g a s p e c t , a f f e c t e d t h e s u r f a c e t e m p e r a t u r e and e v a p o t r a n s p i r a t i o n , i m p o r t a n t c o n s i d e r a t i o n s i n an a r e a w i t h a l a r g e summer w a t e r d e f i c i t . E r r i n g t o n ' s (1975) c o n c l u s i o n t h a t n a t u r a l p l a n t i n v a s i o n o f w a s t e r o c k was v e r y s l o w i n t h i s e n v i r o n m e n t was s u p p o r t e d by L a v k u l i c h e t a l . (1976) who found v e r y l i t t l e p l a n t c o l o n i z a t i o n on w a s t e r o c k dumps a t t h e ne a r b y Texada m e t a l mine. The growth o f v o l u n t e e r v e g e t a t i o n was much s t r o n g e r where n a t u r a l u n c o n s o l i d a t e d m a t e r i a l s were 23 p r e s e n t . The f a s t e r p l a n t c o l o n i z a t i o n on n a t u r a l o v e r b u r d e n was a t t r i b u t e d t o a f i n e r t e x t u r e . I n Canada, t h e j u r i s d i c t i o n w i t h t h e most r i g o r o u s mine r e c l a m a t i o n r e q u i r e m e n t s i s A l b e r t a . The A l b e r t a government has c a r r i e d o u t a t h o r o u g h r e s e a r c h program t o show why and how t h e i r r e q u i r e m e n t s must be met ( e . g . , Z i e m k i e w i c z , 1985). U n f o r t u n a t e l y d i f f e r e n c e s i n t h e e n v i r o n m e n t , i n t h e t y p e o f mines, and i n t h e end l a n d use o b j e c t i v e s p r e v e n t one from u s i n g most o f t h i s t e c h n o l o g y on t h e humid, west c o a s t o f B.C.. I n B.C. t h e government has p l a y e d a l e s s a c t i v e r o l e i n r e c l a m a t i o n r e s e a r c h . Most o f t h e work i n B.C. has been done by i n d i v i d u a l companies o r by t h e i r c o n s u l t a n t s . As a r e s u l t , r e s e a r c h r e s u l t s g e n e r a l l y a r e p u b l i s h e d o n l y when t h e y can be used f o r p u b l i c r e l a t i o n s o r i n d e a l i n g w i t h r e g u l a t o r y a g e n c i e s . Thus t h e knowledge o b t a i n e d o f t e n i s n o t r e a d i l y a c c e s s i b l e . I n B.C., most o f t h e e f f o r t i n mine r e c l a m a t i o n has been d i r e c t e d a t p r o d u c i n g s u r f a c e c o v e r s o f agronomic g r a s s e s and legumes. A l a r g e number o f mines have succeeded i n t h i s r e g a r d . Agronomic s p e c i e s a r e a t t r a c t i v e f o r r e c l a m a t i o n f o r a number o f r e a s o n s : - cheap seed s o u r c e s o f known q u a l i t y a r e a v a i l a b l e , - t h e y a r e c o m p a t i b l e w i t h amendments s u c h as f e r t i l i z e r and l i m e s t o n e , - ease o f a p p l i c a t i o n and seed s t o r a g e , - t h e y grow i n a wide range o f c o n d i t i o n s , - t h e y grow r a p i d l y , p r o d u c i n g an a e s t h e t i c a l l y 24 p l e a s i n g e r o s i o n - c o n t r o l l i n g c o v e r . The a d a p t i o n t o a wide range o f c o n d i t i o n s i s i n p a r t due t o t h e g r e a t number o f s p e c i e s a v a i l a b l e . A d apted s p e c i e s can be found f o r a l l b u t t h e h a r s h e s t c o n d i t i o n s (Watson e t a l . , 1 980). I n some c a s e s i n d i v i d u a l s p e c i e s a r e t o l e r a n t o f a wide range o f c o n d i t i o n s . F o r example, r e d f e s c u e has p e r f o r m e d w e l l on t h e west c o a s t o f Vancouver I s l a n d ( H i l l i s & Home, 1984), a t a v a r i e t y o f e l e v a t i o n s i n s o u t h e a s t e r n B.C. ( F r a s e r , 1984), on a number o f s u b s t r a t e s a t P i n c h i Lake n e a r F o r t S t . James ( W r i g h t & G a r d i n e r , 1980), and t h r o u g h o u t t h e Yukon (Y o u n k i n & M a r t e n s , 1985). Two d i f f e r e n t approaches f o r u s i n g agronomics a r e i l l u s t r a t e d by t h e work a t Westar and F o r d i n g C o a l M i n e s , mines i n s i m i l a r e n v i r o n m e n t s i n the. Crows N e s t Pass a r e a o f s o u t h e a s t B.C. A t Westar C o a l L t d . , t h e i n i t i a l p u r p o s e o f r e c l a m a t i o n was t o r e d u c e s u r f a c e e r o s i o n , p r o v i d e o r g a n i c m a t t e r f o r n u t r i e n t c y c l i n g and f a u n a l a c t i v i t y , and p r o v i d e f o r a g e f o r w i l d l i f e (Westar, 1983). To a c c o m p l i s h t h i s , s t a n d s p r e d o m i n a n t l y c o m p r i s e d Of g r a s s s p e c i e s were e s t a b l i s h e d and t h e n r e f e r t i l i z e d a n n u a l l y w i t h 200 kg/ha o f 13-16-10. To d e t e r m i n e when a n n u a l r e - f e r t i l i z a t i o n c o u l d be s t o p p e d , s t u d i e s were c a r r i e d o u t t o see how l o n g i t t o o k t o d e v e l o p adequate n u t r i e n t c y c l i n g ( e . g . , F y l e s , 1984). F y l e ' s (1984) s t u d y o f N dynamics showed t h a t once f e r t i l i z a t i o n c e a s e d , r o o t N: s h o o t N r a t i o s i n c r e a s e d t o l e v e l s s i m i l a r t o n a t i v e g r a s s l a n d s . The dependence o f t h e g r a s s e s on new f e r t i l i z e r N d e c l i n e d s i g n i f i c a n t l y 2 t o 5 25 y e a r s a f t e r e s t a b l i s h m e n t . Based on t h e s e r e s u l t s , m aintenance f e r t i l i z a t i o n i s c o n t i n u e d f o r 5 t o 8 y e a r s a f t e r t h e g r a s s c o v e r has been e s t a b l i s h e d ( F r a s e r 1984). F r a s e r (1984) r e p o r t e d t h a t w i t h i n g r a s s s t a n d s t h e p r o p o r t i o n o f d i f f e r e n t s p e c i e s f l u c t u a t e d m a r k e d l y from y e a r t o y e a r . On exposed d r y e r s i t e s t h e dominant g r a s s s p e c i e s was r e d f e s c u e . A t l o w e r e l e v a t i o n and on m o i s t e r s i t e s t h e r e was a l a r g e r component o f t a l l g r a s s e s s u c h as bromegrass (Bromus i n e r m i s Leys) and o r c h a r d g r a s s ( D a c t v j . i s  a l o m e r a t a L.) Y i e l d s a v e r a g e d 800-1500 kg/ha above ground w e i g h t on t h e d r i e r s i t e s and 1000-3000 kg/ha on t h e m o i s t e r a r e a s . I n c o n t r a s t t o Westar, a t F o r d i n g C o a l t h e s h o r t t e r m r e c l a m a t i o n o b j e c t i v e i s t o e s t a b l i s h legumes. Based on a number o f greenhouse and f i e l d t r i a l s , F o r d i n g d e v e l o p e d t h e f o l l o w i n g r e c i p e f o r r e c l a m a t i o n ( F o r d i n g C o a l , 1983). S e p a r a t e seed mixes a r e used a t low and h i g h e l e v a t i o n s . A t h i g h e l e v a t i o n t h e main s p e c i e s used i s s a i n f o i n ( O n o b r v c h i s  v i c i i f o l i a S c o p . ) , w h i l e a t low e l e v a t i o n i t i s a l f a l f a (Medicago s a t i v a L . ) . The seed mixes a l s o i n c l u d e some g r a s s s p e c i e s , b u t t h e s e e d i n g r a t e f o r g r a s s e s i s k e p t down t o 56 kg/ha t o e n s u r e t h a t t h e legumes have room t o d e v e l o p . The f e r t i l i z e r r a t e i s 225 kg/ha o f 11-55-0. F i e l d t r i a l s have shown t h a t t h e h i g h P and low N f e r t i l i z e r f a v o u r s t h e growth o f legumes v e r s u s t h e g r a s s e s . K i s n o t r e q u i r e d , p r e s u m a b l y because t h e r o c k (mica i n s h a l e ) i s an adequate K s o u r c e . A t F o r d i n g , f e r t i l i z e r o n l y needs t o be a p p l i e d a t t h e t i m e o f s e e d i n g because legumes can use a t m o s p h e r i c N. A l t h o u g h agronomic p l a n t c o v e r s a t b o t h mines have s u s t a i n e d v i g o r o u s growth, i t i s u n c l e a r whether t h i s w i l l c o n t i n u e i n d e f i n i t e l y . There has been no p r e v i o u s r e s e a r c h w i t h t h e s e s p e c i e s i n t h i s e n vironment. I t i s hoped t h a t n a t i v e s p e c i e s w i l l g r a d u a l l y r e p l a c e t h e a g r o n o m i c s , b u t t o d a t e t h a t has n o t o c c u r r e d ( F r a s e r , 1984). As a r e s u l t b o t h mines a r e now i n v e s t i g a t i n g how t h e y may i n c o r p o r a t e n a t i v e h e r b a c e o u s s p e c i e s i n t o t h e ground c o v e r t o e n s u r e i t s l o n g t e r m s t a b i l i t y . F o r d i n g and Westar have a l s o c a r r i e d o u t t r i a l s w i t h woody s p e c i e s . A t b o t h mines, l o d g e p o l e p i n e ( P i n u s  c o n t o r t a v a r . l a t i f o l i a . Engelm). has grown f a s t e r t h a n e i t h e r D o uglas f i r (Pseudotsuga m e n z i e s i i C a r r . ) o r Engelmann s p r u c e ( P i c e a e n g e l m a n n i i P e r r y ) ( F o r d i n g , 1983; W e s t a r , 1983). S a l i x and P o p u l u s s p e c i e s have a l s o grown w e l l , however a l l s p e c i e s have grown p o o r l y when p l a n t e d i n dense h e r b a c e o u s c o v e r s . Browse has a l s o been a p r o b l e m , e s p e c i a l l y f o r t h e d e c i d u o u s s p e c i e s ( F o r d i n g , 1983). Of t h e h a r d r o c k mines i n B.C. one o f t h e most t h o r o u g h r e c l a m a t i o n programs was c a r r i e d o u t by Cominco a t P i n c h i L ake. P i n c h i Lake was an open p i t and u nderground Hg mine, a p p r o x i m a t e l y 50 km n o r t h w e s t o f F o r t S t . James. The mine c e a s e d o p e r a t i o n , i n 1975, and s i n c e t h e n t r i a l s have been r u n on a v a r i e t y o f m a t e r i a l s t o t e s t d i f f e r e n t g r a s s and legume s p e c i e s , f e r t i l i z e r r a t e s , t h e e l i m i n a t i o n o f 27 maintenance f e r t i l i z e r , s e e d i n g r a t e s , and f a l l v e r s u s s p r i n g s e e d i n g . The s h o r t t e rm r e c l a m a t i o n o b j e c t i v e a t P i n c h i Lake was t o e s t a b l i s h an agronomic c o v e r t h a t would: - improve i n f i l t r a t i o n and p r e v e n t e r o s i o n , - r e t a i n and r e c y c l e n u t r i e n t s added as f e r t i l i z e r and we a t h e r e d from r o c k , - p r o v i d e c o v e r a g e and p r o t e c t i o n f o r w i l d l i f e , - improve t h e s i t e ' s appearance. As a r e s u l t o f r e s e a r c h work, G a r d i n e r & S t a t h e r s (1978) c o n c l u d e d t h a t a s e l f - s u s t a i n e d a l f a l f a - d o m i n a t e d s t a n d c o u l d be e s t a b l i s h e d . The r e c l a m a t i o n p r e s c r i p t i o n p r o d u c e d a 93% v e g e t a t i o n c o v e r , a 79% legume c o v e r and 6200 kg/ha o f biomass. When t h e a n n u a l maintenance f e r t i l i z a t i o n was s t o p p e d t h e most p e r s i s t e n t s p e c i e s were a l f a l f a and c r e e p i n g r e d f e s u e . S p r i n g sowing r e s u l t e d i n a g r e a t e r legume c o v e r t h a n i f t h e seed mix was sown i n t h e f a l l ( W r i g h t & G a r d i n e r , 1980). S u r v e y s c a r r i e d o u t a t P i n c h i Lake i n t h e 1983 showed t h a t a t h i c k humus l a y e r had d e v e l o p e d b e n e a t h v e g e t a t i o n , w h i c h had s u s t a i n e d growth w i t h o u t maintenance f e r t i l i z e r s i n c e 1975. From 1980 t o 1983 t h e g r a s s g r o w t h and c o v e r d e t e r i o r a t e d , w h i l e t h e c o v e r o f a l f a l f a and a l s i k e c l o v e r ( T r i f o l i u m h y bridum L.) i n c r e a s e d . T h i s was a t t r i b u t e d t o a s o i l N d e f i c i e n c y . On many dumps i n c r e a s i n g numbers o f p o p l a r ( P o p u l u s spp.) and w i l l o w were a p p e a r i n g above t h e t a l l a l f a l f a . A l d e r and s p r u c e were a l s o n o t e d on a number o f dumps ( P i n c h i Lake, 1983). 28 One r e a s o n f o r t h e s t r o n g e r n a t u r a l i n v a s i o n on t h e w a s t e r o c k dumps a t P i n c h i Lake, r e l a t i v e t o Westar and F o r d i n g , was t h e w e t t e r c l i m a t e . V o g e l (1980), r e v i e w i n g r e s e a r c h i n t h e e a s t e r n U.S., c o n c l u d e d t h a t t r e e s grown i n c o m b i n a t i o n w i t h agronomic s p e c i e s seemed t o be most a f f e c t e d by c o m p e t i t i o n f o r m o i s t u r e , and t h a t t r e e s u r v i v a l was g r e a t e s t where adequate w a t e r was a v a i l a b l e . V o g e l (1980) a l s o n o t e d t h a t w h i l e dense s t a n d s o f legumes may i n i t i a l l y r e d u c e t r e e s u r v i v a l , t h e growth o f s u r v i v i n g t r e e s i n c r e a s e d . A n o t h e r common cause o f s e e d l i n g m o r t a l i t y i s c l i p p i n g by r o d e n t s . T h i s i s more pronounced when t r e e s a r e grown i n c o n j u n c t i o n w i t h a h e r b a c e o u s c o v e r , as g r a s s e s and legumes h i d e t h e r o d e n t s from p r e d a t o r s ( W isch, 1985). The c l o s e s t l a r g e mines t o K i t s a u l t a r e t h e S c o t t y G o l d and t h e Granduc mines. However b o t h mines a r e l o c a t e d above t h e t r e e l i n e and t h e i r r e c l a m a t i o n does n o t i n c l u d e v e g e t a t i o n ( e . g . , W a l k e r , 1985). The Tasu mine on t h e Queen C h a r l o t t e I s l a n d s i s a t a s i m i l a r l a t i t u d e t o K i t s a u l t . A g ronomics were t e s t e d a t Tasu, b u t n a t u r a l i n v a s i o n by r e d a l d e r was so q u i c k t h a t i t was d e c i d e d t h a t no a r t i f i c i a l p l a n t e s t a b l i s h m e n t was r e q u i r e d ( W e s t f r o b , 1981). The m a j o r d i f f e r e n c e between t h e Tasu and K i t s a u l t m i n e s i t e s i s e l e v a t i o n , as t h e Tasu m i n e s i t e i s a t sea l e v e l . R a p i d r e d a l d e r c o l o n i z a t i o n o c c u r s a t sea l e v e l on d i s t u r b e d s u r f a c e s o f t h e K i t s a u l t T o w n s i t e . L i k e Tasu and t h e K i t s a u l t T o w n s i t e , t h e I s l a n d Copper Mine on t h e west c o a s t o f Vancouver I s l a n d i s a l s o a t sea l e v e l . A t I s l a n d Copper, r e c l a m a t i o n r e s e a r c h s t a r t e d i n 1971 and a t p r e s e n t some dumps a r e i n t h e p r o c e s s o f b e i n g r e c l a i m e d t o a f o r e s t e d s t a t e . A c c o r d i n g t o H i l l i s and H ome (1984) t h e r e c i p e f o r w a s t e r o c k dump r e c l a m a t i o n a t I s l a n d Copper i s as f o l l o w s . S u r f a c e s a r e r e c o n t o u r e d t o c r e a t e g e n t l e s l o p e s and t h e n capped w i t h 30 cm o f t i l l . N e x t 110''kg/ha o f seed and 450 kg/ha o f f e r t i l i z e r a r e a p p l i e d . The seed mix i n c l u d e s 40% r e d f e s c u e , 25% r y e g r a s s e s ( L o l i u m s p e c i e s ) and 25% o f t h e legumes, a l f a l f a and w h i t e c l o v e r ( T r i f o l i u m repens L . ) . The f e r t i l i z e r a n a l y s i s i s 27-18-9 f o r s p r i n g p l a n t i n g and 13-16-10 f o r f a l l p l a n t i n g . L a t e r , a t some u n s p e c i f i e d t i m e , r e d a l d e r s e e d l i n g s a r e t r a n s p l a n t e d o n t o t h e s i t e . L o d g e p o l e p i n e . ' • v. ' • • ' ' ^ s e e d l i n g s were t e s t e d b u t t h e i r growth was much s l o w e r t h a n t h e a i d e r . I s l a n d Copper's a n n u a l r e c l a m a t i o n r e p o r t s do h o t s a y w h e t her agronomics were r e q u i r e d t o p r e v e n t e r o s i o n o r i f t h e y a c c e l e r a t e d t r e e g rowth. Nor was any d a t a p r e s e n t e d t o show why r e d a l d e r needed t o be a r t i f i c i a l l y e s t a b l i s h e d . P r o b a b l y t h e most e x t e n s i v e mine r e c l a m a t i o n program i n t h e P a c i f i c N o r t h w e s t i s t h a t c a r r i e d o u t a t t h e c o a l mine n e a r C e n t r a l i a , Washington (Wisch, 1985). P r e s e n t r e g u l a t i o n s f o r c e t h e mine t o r e a p p l y t h e o r i g i n a l t o p s o i l . However t h e r e a r e a l a r g e number o f a r e a s t h a t were d i s t u r b e d p r i o r t o t h e p r e s e n t r e g u l a t i o n s . These a r e a s , 30 w h i c h c o n s i s t o f s u b s o i l , were found t o be d e f i c i e n t i n N and i n s o i l b i o l o g i c a l a c t i v i t y . To r e c t i f y t h i s , s u b s o i l a r e a s were i n i t i a l l y v e g e t a t e d w i t h s e l e c t e d g r a s s e s , and p r o c e e d e d t h r o u g h a m u l t i - y e a r sequence o f t i l l a g e , sewage s l u d g e i n j e c t i o n , and c r o p p i n g u n t i l n u t r i e n t l e v e l s r e a c h e d t a r g e t l e v e l s o f 1,100-1,146 kg/ha o f t o t a l N. T h i s t o o k 3 t o 6 y e a r s t o a c c o m p l i s h . Douglas f i r , i n o c u l a t e d w i t h e s s e n t i a l m y c o r r h i z a e , were t h e n p l a n t e d . " E a r l y e f f o r t s t o p l a n t t r e e s i n d i s c e d g r a s s r e s i d u e s r e s u l t e d i n h i g h m o r t a l i t y from b u r g e o n i n g p o p u l a t i o n s o f v o l e s , M i c r o t u s  t o w n s e n d i i Bachman, (Wisch, 1985)". D u r i n g p e r i o d s o f d r o u g h t , c o m p e t i t i o n f o r m o i s t u r e was a l s o f e l t t o be a p r o b l e m . On some a r e a s , S i t k a a l d e r has been i n t e r p l a n t e d w i t h t h e Douglas f i r . The p l a n i s t h a t w i t h i n 10-15 y e a r s D o uglas F i r w i l l shade o u t t h e a l d e r . I n t h e meantime, t h e S i t k a a l d e r i s e x p e c t e d t o add 5-8 kg/ha o f N a n n u a l l y . S i t k a a l d e r was a l s o used t o b l o c k t h e encroachment o f non-d e s i r a b l e s p e c i e s and improve t h e i n t e r n a l s o i l s t r u c t u r e and s u r f a c e s t a b i l i t y . I n c o m p a r i s o n w i t h K i t s a u l t , C e n t r a l i a has a more b e n i g n c l i m a t e ( e . g . , Douglas f i r ) and g e n t l e r l a n d s c a p e , and t h e s u r f a c e t o be v e g e t a t e d c o n t a i n s more f i n e s t h a n w a s t e r o c k (Wisch, 1985). 2.5 R e c l a m a t i o n R e s e a r c h a t K i t s a u l t R e c l a m a t i o n r e s e a r c h was s t a r t e d a t t h e K i t s a u l t m i n e s i t e i n 1970. D e s c r i p t i o n s o f t h e t r i a l s b u i l t and t h e 31 m o n i t o r i n g r e s u l t s were s u b m i t t e d t o t h e M i n i s t r y o f Energy Mines and P e t r o l e u m R e s o u r c e s i n t h e a n n u a l r e c l a m a t i o n r e p o r t . T h i s i n f o r m a t i o n i s summarised i n P r i c e (1982). 2.6 S o i l Development on Mine Wastes L i k e t h e s o i l development on r e c e n t l y exposed m o r a i n e s ( U g o l i n i , 1967), t h e f i r s t change i n t h e morphology o f mine waste s i s u s u a l l y t h e development o f a d a r k c o l o u r e d A h o r i z o n . F o r example, on a m i x t u r e o f s a n d s t o n e and s i l t s t o n e w a s t e r o c k i n S.W. V i r g i n i a , f o u r y e a r s o f v i g o r o u s g r a s s g r o w t h c r e a t e d a 4 cm deep Ah h o r i z o n ( R o b e r t s e t a l . , 1988b). Under t h e same c o n d i t i o n s p r e t r e a t m e n t s w i t h sawdust and s l u d g e deepened t h e Ah t o 7 and 14 cm r e s p e c t i v e l y . I n P e n n s y l v a n i a m i n e s o i l s ( C i o l k o s z e t a l . , 1985), i t t o o k 3 t o 13 y e a r s t o form an Ah h o r i z o n , 6 t o 20 y e a r s t o form an Ah, AC sequence, and 12 t o 28 y e a r s t o form an Ah, Bm sequence. S o i l h o r i z o n s were i d e n t i f i e d by t h e i r c o l o u r , as even t h e Ah h o r i z o n showed weak s t r u c t u r a l d evelopment. R o b e r t s e t a l . (1988b) found some s o i l d evelopment, i n c l u d i n g s t r u c t u r e , b e n e a t h t h e A h o r i z o n , b u t i t l a c k e d t h e c o n t i n u i t y o r s t r e n g t h t o c r e a t e a cambic B h o r i z o n . A c c o r d i n g t o S m i t h e t a l . (1971), t h e b u l k d e n s i t y , p o r o s i t y , and c o a r s e fragment c o n t e n t o f i r o n o r e s l a g i n W. V i r g i n i a had n o t changed 70 t o 130 y e a r s a f t e r b e i n g abandoned. The o n l y p h y s i c a l change a t t h e s e s i t e s was a l o s s o f c l a y from t h e upper 5 cm. I n P e n n s y l v a n i a 32 m i n e s o i l s , i t t o o k 15 t o 20 y e a r s f o r e l u v i a t i o n t o c r e a t e c l a y s k i n s and about 100 y e a r s f o r a s i g n i f i c a n t p o r t i o n o f t h e c l a y t o move i n an Iowa s p o i l c o m p r i s e d o f l o e s s ( H a l l b e r g e t a l . 1978). I n c o n t r a s t , a f t e r e i g h t y e a r s , t h e 0 t o 5 cm l a y e r i n a r e c l a i m e d c o l l i e r y s p o i l i n N.E. E n g l a n d had a l o w e r b u l k d e n s i t y and s t o n e c o n t e n t t h a n t h e m a t e r i a l below (Rimmer, 1982). I n 0 t o 178 y e a r o l d c o l l i e r y waste i n S.W. E n g l a n d , p a r t i c l e breakdown was r e s t r i c t e d t o t h e upper 20 cm (Down, 1975). Most o f t h e d i s i n t e g r a t i o n o c c u r r e d q u i t e q u i c k l y . The > 9.5 mm f r a c t i o n d e c l i n e d from 39 t o 1% w i t h i n 21 y e a r s . The q u a n t i t y o f t h e 9.5-4.0 mm f r a c t i o n a l s o d e c r e a s e d , w i t h a c o n c u r r e n t i n c r e a s e i n t h e 4-2 mm and 2-1 mm f r a c t i o n s . No s i g n i f i c a n t d i f f e r e n c e s were found i n t h e < 500 um f r a c t i o n a f t e r 21 t o 55 y e a r s . A f t e r r e c r e a t i n g r o c k d i s i n t e g r a t i o n i n t h e l a b o r a t o r y w i t h a l t e r n a t i n g w e t / d r y and f r e e z e / t h a w c y c l e s , Down (1975) a t t r i b u t e d t h e f i e l d changes t o p h y s i c a l w e a t h e r i n g . S c h a f e r e t a l . (1980) n o t e d t h a t i n a c o a l s p o i l i n S.E. Montana, t h e p r o p o r t i o n o f s o f t f r a g m e n t s d e c r e a s e d n e a r t h e s u r f a c e , w h i l e " r e s i s t a n t " c o a r s e fragments had a c o n s t a n t volume w i t h d e p t h . S c h a f e r e t a l . (198 0) were n o t c l e a r as t o t h e i d e n t i t y o f t h e s o f t f r a g m e n t s , o t h e r t h a n t o say t h a t t h e y d i s i n t e g r a t e d i n wa t e r . R o b e r t s e t a l . (1988a) i n S.W. V i r g i n i a , a l s o o b s e r v e d a r a p i d d e c l i n e i n t h e c o a r s e fragment c o n t e n t a t 0-5 cm i n b o t h s a n d s t o n e and s i l t s t o n e w a s t e r o c k . Changes i n f i n e r 33 f r a c t i o n s were l i m i t e d t o t h e s i l t s t o n e , whose sand f r a c t i o n d e c r e a s e d from 59 t o 48% and s i l t f r a c t i o n i n c r e a s e d from 30 t o 40%. D i f f e r e n c e s o c c u r r e d a t b o t h 0-5 cm and 25-30 cm, t h e two depths sampled, and were a t t r i b u t e d t o t h e d i s s o l u t i o n o f c a r b o n a t e cements. As a r e s u l t o f i t s f i n e r t e x t u r e , t h e < 2 mm w a t e r h o l d i n g c a p a c i t y was h i g h e s t i n t h e s i l t s t o n e . On a t o t a l w e i g h t b a s i s , t h e w a t e r h o l d i n g c a p a c i t y was h i g h e s t i n t h e s a n d s t o n e , w h i c h c o n t a i n e d l e s s c o a r s e f r a g m e n t s (65% v s 7 7 % ) . V i g o r o u s p l a n t growth and o r g a n i c p r e t r e a t m e n t s , l i k e sewage s l u d g e , can d r a m a t i c a l l y i n c r e a s e t h e s u r f a c e o r g a n i c c o n t e n t o f a mine waste. On san d s t o n e and s i l t s t o n e w a s t e r o c k i n S.E. Montana, S c h a f e r e t a l . (1980) o b s e r v e d t h a t 0-10 cm o r g a n i c - C l e v e l s r e a c h e d c o n t e n t s found i n n a t u r a l s o i l s ( e.g. 5%) a f t e r 30 y e a r s o f g r a s s growth, b u t a t 20-50 cm would n o t r e a c h n a t u r a l l e v e l s f o r 400 y e a r s . I n t h e s t u d y c a r r i e d o u t by R o b e r t s e t a l . (1988b), t h e o r g a n i c c o n t e n t a t 0-5 cm a t t h e end o f t h e t h i r d g r o w i n g season was 2% i n t h e w a s t e r o c k c o n t r o l , 8.5% f o r t h e sawdust t r e a t m e n t , and from 4 t o 7% f o r v a r i o u s amounts o f sewage s l u d g e . I n 8 y e a r o l d c o l l i e r y wastes i n N.E. E n g l a n d , t h e 0-5 cm o r g a n i c c o n t e n t was 7% on s i t e s s u p p o r t i n g v i g o r o u s agronomic growth (Rimmer, 1982). O r g a n i c a d d i t i o n s were a l s o s i g n i f i c a n t on o l d e r n a t u r a l l y i n v a d e d mine wastes (Down, 1975; Anderson, 1977). On 70 t o 130 y e a r o l d i r o n o r e s l a g i n W. V i r g i n i a , t h e r a t e s o f N a d d i t i o n and t h e N c o n t e n t n e a r t h e s u r f a c e were 34 comparable t o n a t u r a l s o i l s (Smith e t a l . , 1971). Data f o r N i n t h e mine wastes s t u d i e d i n S.W. V i r g i n i a i l l u s t r a t e d how a h i g h c o a r s e fragment c o n t e n t may c o n c e n t r a t e i n p u t s i n t h e < 2 mm f r a c t i o n . D e s p i t e s i m i l a r l e v e l s o f N on a v o l u m e t r i c b a s i s , t h e c o a r s e r s i l t s t o n e w a s t e r o c k c o n t a i n e d h i g h e r < 2 mm N c o n c e n t r a t i o n s t h a n t h e s a n d s t o n e w a s t e r o c k ( R o b e r t s e t a l . , 1988a). I n t h i s s t u d y , a t 0-5 cm N l e v e l s were 1.5 t o 2 t i m e s h i g h e r t h a n a t 25-30 cm, and i n c r e a s e d each y e a r . B i c a r b o n a t e e x t r a c t a b l e P l e v e l s were a l s o s i g n i f i c a n t l y h i g h e r a t 0-5 cm t h a n a t 25-30 cm, and i n c r e a s e d w i t h t h e o r g a n i c s u r f a c e t r e a t m e n t s , sewage s l u d g e and sawdust. D i f f e r e n c e s p r o b a b l y r e s u l t e d from t h e P added i n t h e f e r t i l i z e r and o r g a n i c amendments. O r g a n i c amendments might a l s o have r e d u c e d t h e f i x a t i o n o f P by a v a i l a b l e Fe. The l e v e l s o f a v a i l a b l e Fe i n c r e a s e d d r a m a t i c a l l y from t h e end o f t h e f i r s t t o t h e end o f t h e second g r o w i n g season, and t h e n d e c r e a s e d s l i g h t l y by t h e end o f t h e t h i r d g r o w i n g season. W i t h t h e advent o f w e a t h e r i n g , one o f t h e major c h e m i c a l changes o b s e r v e d i n mine wastes i s t h e d i s s o l u t i o n o f s o l u b l e s a l t s and c a r b o n a t e s . I n a r i d c l i m a t e s , r e s e a r c h on mine wast e s has shown t h a t s o l u b l e s a l t s were l o s t from t h e upper 50 cm i n t e n s o f y e a r s , w h i l e c a r b o n a t e s w i l l t a k e t h o u s a n d s o f y e a r s t o remove (Anderson, 1977; S c h a f e r e t a l . , 1980). I n humid e n v i r o n m e n t s , t h e removal o f s a l t s and c a r b o n a t e s s h o u l d be q u i c k e r . F o r example, i n t h e s t u d y 35 c a r r i e d o ut by R o b e r t s e t a l . (1988a and b ) , t h e l o s s o f c a r b o n a t e s caused t h e l e v e l s o f exchangeable Ca and Mg t o d e c r e a s e s i g n i f i c a n t l y i n t h e f i r s t few y e a r s . Even w i t h g r e a t e r l e a c h i n g , m i n e s o i l s i n t h e e a s t e r n U.S.A. g e n e r a l l y c o n t a i n e d h i g h e r l e v e l s o f a v a i l a b l e c a t i o n s t h a n n a t u r a l s o i l s ( S m i t h e t a l . , 1971; C i o l k o s z e t a l . , 1985). T h i s i s a t t r i b u t e d t o t h e i r y o u t h and, i n some c a s e s , l a r g e r amounts o f r a p i d l y w e a t h e r i n g m i n e r a l s i n t h e minewastes. A n o t h e r change o b s e r v e d i n mine wastes was a d e c l i n e i n pH. I n t h e s t u d y c a r r i e d o ut by R o b e r t s e t a l . (1988a), s m a l l changes i n pH were a t t r i b u t e d t o t h e l e a c h i n g o f c a r b o n a t e s and base c a t i o n s , and t o n i t r i f i c a t i o n o f f e r t i l i z e r N. The m a t e r i a l s i n t h i s s t u d y c o n t a i n e d l i t t l e o r no s u l p h i d e m i n e r a l s . I n t h e P e n n s y l v a n i a mine s o i l s s t u d y ( C i o l k o s z e t a l . , 1985), seven o f t h e t w e n t y f o u r m i n e s o i l s had two o r more h o r i z o n s a t pH 4.0 o r l e s s , a f a c t o r a t t r i b u t e d t o s u l p h i d e o x i d a t i o n . N a t u r a l s o i l s i n t h e a r e a seldom have pH v a l u e s < 4.0. I n t h e c o l l i e r y waste s t u d i e d i n S.W. E n g l a n d , t h e pH dropped t o 3.0 i n f i v e y e a r s and r o s e back up t o 6.7 by 178 y e a r s (Down, 1975). Changes a s s o c i a t e d w i t h a d e c r e a s e d pH i n c l u d e t h e r e l e a s e o f K from mica f o r m i n g v e r m i c u l i t e ( S m i t h e t a l . , 1971) and t h e r e d i s t r i b u t i o n o f t r a c e m e t a l s (Chase and W a i n w r i g h t , 1983). I n a 100 y e a r o l d Cu s m e l t e r waste i n Wales, t h e drop i n pH from 4.3 t o 4.0 a t 10 cm p a r a l l e l e d a s i m i l a r d r o p i n EDTA and a c e t i c a c i d e x t r a c t a b l e Cu, Zn, and e x t r a c t a b l e Pb. Deeper i n t h e p r o f i l e , t h e r e was no change 36 i n t h e c o n c e n t r a t i o n o f a v a i l a b l e Pb. However, t h e r e were l a r g e peaks o f e x t r a c t a b l e Cu a t 40 cm (pH 4.5) and 1.54 m (pH 6.0), and Zn a t 80 cm (pH 5.6). Long term c o n t i n u o u s l e a c h i n g s t u d i e s r u n i n t h e l a b o r a t o r y i n d i c a t e d t h a t pH g r a d i e n t s l a r g e l y d e t e r m i n e d t h e d i s t r i b u t i o n o f m e t a l s (Chase and W a i n w r i g h t , 1983). S o i l f l o r a and fauna can produce b e n e f i c i a l changes i n t h e p r o p e r t i e s o f mine waste ( E t t e r s h a n k e t a l . , 1978). P r i o r t o e x p o s u r e , mine wastes do n o t c o n t a i n t h e f l o r a and fauna found i n n a t u r a l s o i l s . B i o l o g i c a l a c t i v i t y o f t h i s k i n d may be enhanced by c a p p i n g t h e waste w i t h n a t u r a l t o p s o i l o r by u s i n g n a t i v e p l a n t s p e c i e s ( B i o n d i n i e t a l . , 1985). A l t e r n a t i v e l y a n i m a l s p e c i e s , l i k e g r a s s h o p p e r s o r r o d e n t s , can a c t as v e c t o r s (Pender, 1980). 2.7 N a t u r a l P l a n t S u c c e s s i o n . P r i m a r y p l a n t s u c c e s s i o n and s o i l development can produce a f e r t i l e s o i l and a p r o d u c t i v e f l o r a from b a r r e n i n f e r t i l e l a n d c r e a t e d by n a t u r a l p r o c e s s e s such as r e c e d i n g g l a c i e r s ( U g o l i n i , 1967), mudflows ( D i c k i n s o n & C r o c k e r , 1953) and l a v a f l o w s (Mueller-Dombois & E l l e r i b e r g , 1974). I f c o n d i t i o n s a r e s i m i l a r t o t h o s e on w a s t e r o c k dumps, s t u d i e s o f n a t u r a l p l a n t s u c c e s s i o n may p r o v i d e u s e f u l i n f o r m a t i o n f o r r e c l a m a t i o n . F o r i n s t a n c e , s t u d i e s o f n a t u r a l s u c c e s s i o n c o u l d be used t o show w h i c h n a t i v e s p e c i e s a r e c a p a b l e o f g r o w i n g on t h e w a s t e r o c k dumps, how d i f f e r e n t s p e c i e s and amendments w i l l c o n t r i b u t e t o p l a n t 37 and s o i l development, and how p l a n t and s o i l development w i l l p r o c e e d . I n o r d e r f o r d a t a from n a t u r a l s u c c e s s i o n s t u d i e s t o be a p p l i c a b l e , e n v i r o n m e n t a l f a c t o r s s uch as c l i m a t e , f l o r a , f a una and r o o t i n g media s h o u l d be s i m i l a r . Most o f t h e r e s e a r c h on n a t u r a l p l a n t i n v a s i o n - s o i l development r e l e v a n t t o t h e w a s t e r o c k dumps.at K i t s a u l t has been done on r e c e n t l y d e g l a c i a t e d s i t e s i n B.C. and A l a s k a . D e s p i t e d i f f e r e n c e s i n l i t h o l o g y , p a r t i c l e s i z e and t h e t i m e o f e x p o s u r e , b o t h t h e g l a c i a l m oraines and mine waste r o c k a r e c o a r s e t e x t u r e d , r o c k y , b a r r e n r o o t i n g media. Of t h e a r e a s s t u d i e d , t h o s e most s i m i l a r t o K i t s a u l t a r e G l a c i e r Bay ( C r o c k e r & M a j o r , 1955; Lawrence e t a l . , 1967; U g o l i n i , 1967) and t h e H e r b e r t and M e n d e n h a l l G l a c i e r s ( C r o c k e r & D i c k s o n , 1957) i n s o u t h e a s t e r n A l a s k a . B o t h a r e a s , l i k e K i t s a u l t , have a P a c i f i c c o a s t a l c l i m a t e and d i f f e r e n c e s i n e l e v a t i o n ( t h e K i t s a u l t m i n e s i t e i s h i g h e r ) a r e compensated f o r by d i f f e r e n c e s i n l a t i t u d e . A t G l a c i e r Bay, p l a n t p r o p a g u l e s s t a r t e d t o a r r i v e soon a f t e r t h e g l a c i e r s r e c e d e d . The sequence o f p l a n t c o l o n i z a t i o n on t h e G l a c i e r Bay moraines has been t h e f o l l o w i n g ( U g o l i n i , 1967). S t a g e I 0-5 y r s E a r l y p i o n e e r , l a r g e l y d r y a s (Dryas  drummondii ( R i c h ) ) and w i l l o w spp. w i t h 38 Ecruisetum ( m o i s t s i t e s ) and E p i l o b i u m spp. (sandy s i t e s ) . S t a g e I I Dryas mats up t o 4 m o r more i n 5-15 y r s d i a m e t e r . S t a g e I I I Dryas mats form a u n i f o r m c a r p e t w i t h 15-20 y r s s c a t t e r e d S i t k a a l d e r and b l a c k cottonwood. S t a g e IV Clumps o f a l d e r 2 m o r more h i g h form 20-25 y r s open t h i c k e t s . S t a g e V Clumps o f a l d e r c o a l e s c e . 25-30 y r s S t a g e V I S c a t t e r e d p o p l a r t r e e s emerge above a l d e r . 30-35 y r s S t a g e V I I S i t k a s p r u c e becomes dominant. 40-70 t o A l d e r d i e s o u t . 95 y r s S t a g e V I I I Spruce-hemlock (mountain and w e s t e r n hemlock) f o r e s t , c a r p e t e d w i t h t h i c k moss. The sequence o f p l a n t c o l o n i z a t i o n a t t h e M e n d e n h a l l and H e r b e r t g l a c i e r s was s i m i l a r , e x c e p t t h a t i t l a c k e d t h e 39 g r o w t h o f Dryas ( C r o c k e r & D i c k s o n , 1957). Dryas s p e c i e s have o n l y been r e p o r t e d g r o w i n g on c a l c a r e o u s m a t e r i a l s (Watson e t a l . , 1980; T i s d a l e e t a l . , 1966; V i e r e c k , 1966; G i v e n and Sopar, 1975) and t h u s presumably were u n a b l e t o grow on t h e M e n d e n h a l l and H e r b e r t g l a c i a l m o r a i n e s . Lawrence e t a l . (1967) s u g g e s t e d t h a t D r y a s , w h i c h has a low d e n s e l y m a t t e d c a r p e t - l i k e growth form, c o n t r i b u t e d t o p r i m a r y s u c c e s s i o n o f G l a c i e r Bay by: 1. r a p i d l y s t a b i l i z i n g t h e s o i l s u r f a c e a g a i n s t e r o s i o n , 2. i n c r e a s i n g t h e amount o f s o i l n i t r o g e n t h r o u g h i t s a b i l i t y t o c a r r y o u t N 2 f i x a t i o n , 3. b e g i n n i n g t o d e v e l o p a humus l a y e r , and 4. a i d i n g t h e s u r v i v a l and growth o f woody p l a n t s . V i e r e c k (1966) found Dryas c o n t r i b u t i n g i n t h e same manner t o t h e p l a n t s u c c e s s i o n on g r a v e l outwash t e r r a c e s o f t h e M u l d r o n G l a c i e r , n e a r Mt. M c K i n l e y , A l a s k a . I n a d d i t i o n V i e r e c k (1966) n o t e d t h a t w i n d blown s i l t and sand a c c u m u l a t e d w i t h i n t h e d r y a s clumps. Of D r y a s ' s v a r i o u s c o n t r i b u t i o n s , Lawrence e t a l . (1967) c o n s i d e r e d a i d i n g t h e s u r v i v a l and g r o w t h o f woody p l a n t s t o be t h e most i m p o r t a n t " s i n c e a l d e r i s so much more e f f i c i e n t i n p r o v i d i n g a ground c o v e r and e n r i c h i n g and b u i l d i n g up t h e s u r f a c e o r g a n i c l a y e r . " C o a l e s c e d Dryas mats c r e a t e a more f a v o u r a b l e m i c r o c l i m a t e and i n c r e a s e n u t r i e n t l e v e l s t h r o u g h N 2 f i x a t i o n and l i t t e r d e c o m p o s i t i o n . The i n c r e a s e d N l e v e l i s e s p e c i a l l y i m p o r t a n t f o r . non-N 2 f i x i n g W i l l o w spp. and cottonwood. Lawrence e t a l . (1967) t h o u g h t t h a t d r y a s , by s p e e d i n g up t h e e s t a b l i s h m e n t o f a l d e r , w h i c h i n t u r n prompted t h e g r o w t h o f s p r u c e , speeded up p l a n t s u c c e s s i o n . They s u g g e s t e d t h a t on t h e M e n d e n h a l l g l a c i a l m o r a i n e s i t t o o k an a d d i t i o n a l 20 t o 30 y e a r s f o r a l d e r t h i c k e t s t o c r e a t e an e r o s i o n - r e s i s t a n t b l a n k e t e q u i v a l e n t t o t h a t c r e a t e d by d r y a s a t G l a c i e r Bay. I n c o n t r a s t , C r o c k e r and D i c k s o n (1957), comparing t h e i r r e s u l t s w i t h t h o s e r e p o r t e d by C r o c k e r and M a j o r (1955) a t G l a c i e r Bay, found t h a t a l t h o u g h t h e y were o f t h e same o r d e r o f magnitude, t h e a b s o l u t e amount o f N t h a t a c c u m u l a t e d o v e r e q u i v a l e n t u n i t s o f t i m e was h i g h e r i n t h e M e n d e n h a l l - H e r b e r t sequences. T h i s t h e y a t t r i b u t e d t o M e n d e n h a l l - H e r b e r t * s s u p e r i o r c l i m a t e f o r p l a n t g r o w t h , and t h e much l a r g e r , a r e a d e g l a c i a t e d a t G l a c i e r Bay, r e s u l t i n g i n a s l o w e r , more e r r a t i c p l a n t c o l o n i z a t i o n . Why d i d t h i s complex s u c c e s s i o n t a k e p l a c e ? W i t h i n 5 t o 10 y e a r s o f d e g l a c i a t i o n , young s p r u c e and hemlock were g r o w i n g on t h e m o r a i n e s ( C r o c k e r & D i c k s o n , 1957). So why d i d a s p r u c e f o r e s t n o t d e v e l o p d i r e c t l y ? C r o c k e r and D i c k s o n (1957) s u g g e s t e d t h i s was p a r t i a l l y due t o i n t e r -s p e c i e s c o m p e t i t i o n and t o t h e d i f f e r e n t g r o w t h r a t e s o f t h e p l a n t s p e c i e s . A more i m p o r t a n t r e a s o n was t h e i n a b i l i t y o f s p r u c e , w h i c h c o u l d n o t f i x N, t o u t i l i z e t h e e a r l y s u c c e s s i o n a l e n vironment as f u l l y as t h e more p r o d u c t i v e , ,/ e a r l y s e r a i s p e c i e s . The f a i l u r e o f e a r l y s e r a i s p e c i e s t o 41 s u s t a i n t h e i r dominance r e s u l t e d from t h e i r i n a b i l i t y t o grow i n t h e shade o f t h e i r c o m p e t i t o r s ( C r o c k e r & D i c k s o n , 1957; C r o c k e r & M a j o r , 1955). However, on t h e Muldrow G l a c i e r t e r r a c e s , V i e r e c k (1966) s u g g e s t e d t h a t e i t h e r t h e a c c u m u l a t i o n o f f i n e m a t e r i a l s w i t h i n t h e clumps o r t h e p r e s e n c e o f mosses k i l l e d d r y a s . 2.8 The E a r l y S t a g e s o f N a t u r a l S o i l Development The f i r s t v i s i b l e s i g n o f s o i l f o r m a t i o n a t G l a c i e r Bay was t h e appearance o f a g r a y brown Ah h o r i z o n b e n e a t h a p a t c h y mix o f d r y a s and a c r u s t o f moss, on a r e a s d e g l a c i a t e d f o r a p p r o x i m a t e l y 10 y e a r s . The Ah h o r i z o n r e a c h e d a maximum d e p t h o f 10 cm 41 y e a r s a f t e r d e g l a c i a t i o n . Then, as s p r u c e became dominant and t h e a l d e r d i e d o u t , t h e Ah h o r i z o n was g r a d u a l l y r e p l a c e d by a B h o r i z o n w h i c h grew upwards, c o m p l e t e l y r e p l a c i n g t h e Ah h o r i z o n 85 t o 150 y e a r s a f t e r d e g l a c i a t i o n ( U g o l i n i 1967). An Ae h o r i z o n was f i r s t o b s e r v e d a t G l a c i e r Bay i n a r e a s d e g l a c i a t e d f o r about 150 y e a r s , w h i l e i n t h e M e n d e n h a l l and H e r b e r t sequences t h e Ae d e v e l o p e d a f t e r about 75 y e a r s . Two hundred and f i f t y y e a r s a f t e r d e g l a c i a t i o n none o f t h e Ae h o r i z o n s had i n c r e a s e d i n s i z e and t h e B h o r i z o n s r e m a i n e d s h a l l o w (< 15cm). A t b o t h G l a c i e r Bay and t h e M e n d e n h a l l / H e r b e r t sequences t h e most d r a m a t i c changes i n p r o p e r t i e s o f t h e r o o t i n g media were a s s o c i a t e d w i t h t h e development and d e e p e n i n g o f t h e s u r f a c e o r g a n i c l a y e r . An L l a y e r was 42 f i r s t n o t e d on s i t e s d e g l a c i a t e d f o r 11 y e a r s a t G l a c i e r Bay, and on s i t e s d e g l a c i a t e d f o r 20 and 34 y e a r s r e s p e c t i v e l y a t t h e M e n d e n h a l l and H e r b e r t G l a c i e r s . A t G l a c i e r Bay t h e l i t t e r l a y e r r e a c h e d a maximum t h i c k n e s s o f 20 cm on 150 y e a r o l d s i t e s on w h i c h a l d e r and o t h e r u n d e r s t o r y p l a n t s were s t i l l c o n t r i b u t i n g l i t t e r . A t t h e M e n d e n h a l l and H e r b e r t s i t e s , even a f t e r a l d e r and o t h e r s h r u b s had d i e d o u t , t h e l i t t e r l a y e r c o n t i n u e d t o a c c u m u l a t e , a l t h o u g h a t a r e d u c e d r a t e . A t b o t h G l a c i e r Bay and t h e M e n d e n h a l l / H e r b e r t s i t e s , t h e development o f a h u m i f i e d (FH) l a y e r f o l l o w e d t h e c r e a t i o n o f a l i t t e r l a y e r by about 20 y e a r s . A t G l a c i e r Bay t h e FH l a y e r a c c o u n t e d f o r a p p r o x i m a t e l y h a l f o f t h e d e p t h o f t h e l i t t e r 250 y e a r s a f t e r d e g l a c i a t i o n . L i t t l e o r no m i x i n g o f l i t t e r and m i n e r a l s o i l o c c u r r e d a t any o f t h e s t u d y s i t e s , a l t h o u g h C r o c k e r and D i c k s o n (1957) n o t i c e d some e v i d e n c e o f o r g a n i c m a t t e r i l l u v i a t i o n i n v e r y sandy m o r a i n e s a t t h e H e r b e r t G l a c i e r . C o n c u r r e n t w i t h changes i n p l a n t c o v e r and t h e development o f s o i l h o r i z o n s , t h e r e were marked changes i n s o i l p r o p e r t i e s . Changes were g r e a t e s t i n p r o p e r t i e s a f f e c t e d by t h e a d d i t i o n and d e c o m p o s i t i o n o f o r g a n i c m a t t e r , and t h u s were most pronounced n e a r t h e s u r f a c e . P h y s i c a l changes i n c l u d e d d e c r e a s e s i n b u l k d e n s i t y and an i n c r e a s e i n t h e s o i l m o i s t u r e r e t e n t i o n ( C r o c k e r & D i c k s o n , 1957). A t G l a c i e r Bay, U g o l i n i (1967) found no changes i n t h e sandy loam t e x t u r e and no s i g n o f c l a y movement. Bo t h 43 t h e G l a c i e r Bay and t h e M e n d e n h a l l / H e r b e r t g l a c i a l m o r a i n e s were v e r y s t o n e y . The f i n e e a r t h f r a c t i o n (< 2 mm) o f a r e a s sampled a t t h e M e n d e n h a l l / H e r b e r t v a r i e d from 45% t o 94%, d e s p i t e e f f o r t s t o s e l e c t s i t e s w i t h as few p o s s i b l e s t o n e s . A t G l a c i e r Bay t h e l o c a t i o n s sampled by U g o l i n i (1967) c o n t a i n e d a p p r o x i m a t e l y 50% f i n e s . V a r i a t i o n s i n t h e p e r c e n t s t o n e s w i l l have c o n t r i b u t e d t o t h e v a r i a b i l i t y o b s e r v e d i n b o t h p h y s i c a l and c h e m i c a l p r o p e r t i e s . Summarising t h e changes o b s e r v e d i n c h e m i c a l p r o p e r t i e s w i t h age: t h e pH d e c r e a s e d ; t h e CEC i n c r e a s e d ; s o i l o r g a n i c C i n c r e a s e d ; s o i l N l e v e l s i n c r e a s e d and t h e n l e v e l l e d o f f ; and t h e C/N r a t i o i n c r e a s e d . The r o l e o f o r g a n i c m a t t e r as a s o u r c e o f a c i d i t y was e v i d e n t from t h e low pH o f t h e l i t t e r l a y e r r e l a t i v e t o t h e m i n e r a l s o i l . A t t h e M e n d e n h a l l / H e r b e r t s i t e s t h e l o w e r pH o f t h e FH l a y e r , compared t o t h e undecomposed l i t t e r , was e v i d e n c e t h a t o r g a n i c a c i d s were b e i n g p r o d u c e d as t h e l i t t e r decomposed. I n b o t h s t u d i e s t h e l i t t e r pH d e c l i n e d w i t h t i m e . T h i s may be a t t r i b u t e d t o d e c o m p o s i t i o n and t o changes i n t h e t y p e o f l i t t e r w i t h t h e development o f a c o n i f e r o u s f o r e s t . I n t h e m i n e r a l s o i l , t h e d e c l i n e i n pH was most pronounced a t t h e s u r f a c e . Changes a t l o w e r d e p t h s l a g g e d b e h i n d . Two hundred f i f t y y e a r s a f t e r d e g l a c i a t i o n , on t h e H e r b e r t and G l a c i e r Bay m o r a i n e s t h e pH v a l u e s o f t h e L, FH, B, and C h o r i z o n s were a p p r o x i m a t e l y 4.3, 3.7, 4.7, and 5.8 r e s p e c t i v e l y . D i f f e r e n c e s i n s o i l pH between G l a c i e r Bay and t h e M e n d e n h a l l / H e r b e r t s i t e s r e s u l t e d from t h e p r e s e n c e o f c a r b o n a t e s a t G l a c i e r Bay. Data from G l a c i e r Bay shows t h a t t h e d e c l i n e i n p e r c e n t c a r b o n a t e i n t h e < 2 mm f r a c t i o n was c o r r e l a t e d w i t h t h e pH d e c l i n e , w i t h t h e l o s s o f c a l c i t e o c c u r r i n g f a s t e r t h a n t h a t o f d o l o m i t e . I n t h e Ah h o r i z o n most o f t h e c a r b o n a t e was l o s t between 5 and 24 y e a r s a f t e r d e g l a c i a t i o n . A t 15-25cm, i n t h e C h o r i z o n , most o f t h e c a r b o n a t e was l o s t between 55 and 150 y e a r s a f t e r d e g l a c i a t i o n . Based on changes i n s o i l C, N and C/N, t h e sequence o f s o i l development can be s p l i t i n t o 2 p a r t s ; changes a t t r i b u t e d t o a l d e r and t h o s e o c c u r r i n g under a s p r u c e f o r e s t . I m m e d i a t e l y a f t e r d e g l a c i a t i o n t h e m o r a i n e s a r e wind-swept s u r f a c e s d e v o i d o f n i t r o g e n . T h i s l a c k o f N g i v e s N 2 f i x i n g s p e c i e s a c o m p e t i t i v e advantage. W i t h o u t any c o m p e t i t i o n , N 2 f i x i n g S i t k a a l d e r grew p r o l i f i c a l l y , i t s somewhat p r o s t r a t e , shrubby growth, p r o t e c t i n g t h e s u r f a c e from t h e w i n d and r a p i d l y b u i l d i n g up a f o r e s t f l o o r . As a r e s u l t o f t h e s t r o n g a l d e r growth a l a r g e amount o f N was added t o t h e e cosystem, and o r g a n i c r e s i d u e s i n b o t h t h e f o r e s t f l o o r and t h e m i n e r a l s o i l had a low C/N r a t i o . D u r i n g t h e p e r i o d o f a l d e r growth most o f t h e s o i l o r g a n i c m a t t e r was i n t h e s u r f a c e l i t t e r l a y e r . F o r t y - o n e y e a r s a f t e r d e g l a c i a t i o n a t G l a c i e r Bay, t h e l i t t e r l a y e r was 7 cm t h i c k , c o n t a i n e d 0.11 kg N/m2 and t h e FH l a y e r had a C:N r a t i o o f 21. 45 S p r u c e c a n n o t f i x a t m o s p h e r i c N 2 , so a f t e r s p r u c e r e p l a c e d a l d e r , t h e r a t e o f N a d d i t i o n s t o t h e ecos y s t e m was r e d u c e d . C o n s e q u e n t l y a t G l a c i e r Bay, N l e v e l s i n t h e l i t t e r d e c r e a s e d t o 0.08 kg N/m2 and t h e l i t t e r C:N r a t i o r o s e from 15 t o 30 up t o 45 t o 60. I n c o n t r a s t t o t h e l i t t e r , t h e m i n e r a l s o i l C and N c o n t e n t s under s p r u c e c o n t i n u e d t o r i s e a t much t h e same r a t e as under a l d e r c o v e r . As a r e s u l t o f o r g a n i c m a t t e r a d d i t i o n s , m i n e r a l s o i l CEC l e v e l s i n c r e a s e d from 7.3 t o 14.7 meq/lOOg and t h e a c c u m u l a t i o n o f o r g a n i c m a t t e r and i r o n i n t h e m i n e r a l s o i l c r e a t e d a p o d z o l i c B h o r i z o n . 2.9 W e l l Developed S o i l s S o i l development beyond 250 y e a r s i n t h e G l a c i e r Bay r e g i o n was o b s e r v e d on a s e r i e s o f sand and g r a v e l c o v e r e d (2 t o 4 m e t r e s t h i c k ) , m a r i n e t e r r a c e s ( U g o l i n i & Mann, 1979). The t e r r a c e s were 400, 2-3 x 1 0 3 , and 6-8 x l O 3 y e a r s o l d . The younger two t e r r a c e s were c o v e r e d by a c o n i f e r o u s f o r e s t , dominated by S i t k a s p r u c e and w e s t e r n hemlock. From t h e y o u n g e s t t e r r a c e t o t h e back o f t h e second t e r r a c e , t h e d e p t h o f s u r f a c e l i t t e r i n c r e a s e d from 20 t o 35 cm. On t h e 400 y e a r o l d t e r r a c e , t h e main h o r i z o n was a w e a k l y d e v e l o p e d B, c o n t a i n i n g 0.6% o r g a n i c a l l y complexed Fe. On t h e 2-3 x 1 0 3 t e r r a c e , s o i l s c o n t a i n e d w e l l d e v e l o p e d Ae, Bhf , and B f h o r i z o n s . A t t h e back o f t h e second t e r r a c e t h e Bf had d e v e l o p e d i n t o an i m p e r v i o u s p l a c i c - B h o r i z o n , w h i c h impeded d r a i n a g e . 46 On t h e o l d e s t t e r r a c e , impeded d r a i n a g e had r e s u l t e d i n t h e a c c u m u l a t i o n o f a 1 t o 2 metres deep s u r f a c e p e a t l a y e r , c a p a b l e o f r e t a i n i n g w a t e r t h e whole y e a r r o u n d . Even a f t e r r e d u c i n g c o n d i t i o n s removed t h e p l a c i c h o r i z o n , a n a e r o b i c c o n d i t i o n s were m a i n t a i n e d by t h e deep p e a t . As a r e s u l t o f w a t e r l o g g i n g , t h e v e g e t a t i v e c o v e r on t h e o l d e s t t e r r a c e r a n g e d from. A l a s k a y e l l o w c e d a r (Chamaecyparis n o b t k a t e r i s i s D. Don Spach.) and mountain hemlock t o sphagnum, sedge, and e r i c a c e o u s s h r u b s . The c l o s e s t r e g i o n t o k i t s a u l t f o r w h i c h a s o i l s u r v e y was c a r r i e d o u t was t h e H a z e l t o n a r e a ( W i t t n e b e n , 1984). The s u r v e y e d a r e a c o n t a i n s a number o f p h y s i o g r a p h i c r e g i o n s , i n c l u d i n g t h e Skeena mountains, w h i c h a r e a d j a c e n t t o K i t s a u l t and have s i m i l a r t o p o g r a p h y , e l e v a t i o n , and v e g e t a t i o n t o t h e m i n e s i t e . On f l a t and g e n t l y s l o p e d * v a l l e y f l o o r s and d e p r e s s i o n s i n t h e Skeena m o u n t a i n s , t e r r a i n w h i c h r e s e m b l e s t h a t s t u d i e d a t G l a c i e r Bay, t h e s o i l s were c l a s s i f i e d as M e s i s o l s and p e a t y Rego Humic G l e y s o l s . On more s t e e p l y s l o p e d a r e a s , each p a r e n t m a t e r i a l - v e g e t a t i o n zone c o m b i n a t i o n had a d i f f e r e n t s o i l a s s o c i a t i o n . The K i s p i o x and J a n z e Lake s o i l a s s o c i a t i o n s , formed on t h e c o l l u v i u m i n t h e w e s t e r n and m o u n t a i n hemlock zones r e s p e c t i v e l y , were d e v e l o p e d under c o n d i t i o n s most s i m i l a r 'to K i t s a u l t w a s t e r o c k dumps. C o l l u v i u m had a h i g h c o a r s e fragment c o n t e n t , was g e n e r a l l y s t e e p , w e l l t o r a p i d l y d r a i n e d , and t h u s a n a l a g o u s t o a dump s l o p e . The c o a r s e fragment c o n t e n t o f t e n exceeded 50%, e s p e c i a l l y a t 4 7 h i g h e r e l e v a t i o n . The 50% i s presumably on a p e r volume b a s i s . The p r o p o r t i o n would be even h i g h e r i f r e p o r t e d on a p e r w e i g h t b a s i s . Compared t o a w a s t e r o c k dump t h e main d i f f e r e n c e i n t h e c o l l u v i u m was t h e d e p t h , w h i c h was u s u a l l y l e s s t h a n 2 m e t r e s . K i s p i o x s o i l s a r e g r a v e l l y sandy loams, w i t h a 5 t o 10 cm deep mor l i t t e r l a y e r , c o v e r i n g up t o 10 cm o f Ae, and a B f . S t r o n g l y a c i d solum was u s u a l l y l e s s t h a n 50 cm t h i c k , and r e l a t i v e l y unweathered p a r e n t m a t e r i a l o c c u r r e d w i t h i n 75 cm o f t h e s u r f a c e . Most o f t h e s o i l s were c l a s s i f i e d as O r t h i c H u m o - F e r r i c P o d z o l s . L u v i s o l i c H u m o - F e r r i c P o d z o l s o r P o d z o l i c Gray L u v i s o l s were found on f i n e r t e x t u r e d m a t e r i a l s . G l e y e d Humo-Ferric P o d z o l s o c c u r r e d i n seepage zones. A t h i g h e r e l e v a t i o n i n t h e M o u n t a i n H e m l o c k - S u b a l p i n e F i r Zone ( J a n z e Lake a s s o c i a t i o n ) , t h e main d i f f e r e n c e was t h e g r e a t e r a c c u m u l a t i o n o f i l l u v i a l o r g a n i c m a t t e r c r e a t i n g s u f f i c i e n t l y deep Bhf h o r i z o n s t o change t h e c l a s s i f i c a t i o n t o F e r r o - H u m i c P o d z o l s . I n b o t h v e g e t a t i o n zones, m o r a i n a l m a t e r i a l s had a g r a v e l l y loam o r g r a v e l l y c l a y loam t e x t u r e , were g e n e r a l l y f i n e r t h a n t h e c o l l u v i u m , m o d e r a t e l y p e r v i o u s , and u s u a l l y c l a s s i f i e d as l u v i s o l i c h u m o - f e r r i c o r f e r r o - h u m i c p o d z o l s , d e p ending on t h e e l e v a t i o n . A s u r v e y o f p o d z o l i c s o i l s formed i n S.E. A l a s k a found t h a t r o o t i n g was l a r g e l y c o n f i n e d t o t h e s u r f a c e o r g a n i c l a y e r s and t h e t o p few c e n t i m e t r e s o f t h e m i n e r a l s o i l ( H ellman & Gass 1974). I n t h e s e same s o i l s t h e i n f l u e n c e o f 4 8 p a r e n t m a t e r i a l l i t h o l o g y on s o i l c h e m i c a l p r o p e r t i e s was o n l y e v i d e n t i n t h e l o w e s t h o r i z o n s . T y p i c a l l y t h e s o i l pH was between 3.5 and 4.5 f o r t h e l i t t e r l a y e r s and t h e Ae h o r i z o n s and between 4.5 and 5.5 f o r t h e B h o r i z o n (Hellman and Gass 1974, Stephens 1969). Stephens (1969) i n h i s s t u d y o f S.E. A l a s k a n p o d z o l m i n e r a l h o r i z o n s c o n c l u d e d t h a t o r g a n i c m a t t e r and s e s q u i o x i d e s were p r i m a r i l y r e s p o n s i b l e f o r t h e CEC and w a t e r r e t e n t i o n . A l u m i n o s i l i c a t e c l a y s e i t h e r had n o t formed o r had been l e a c h e d o u t o f t h e p r o f i l e s . 3.0 Summary Wa s t e r o c k from o t h e r Cu-Mo p o r p h y r y mines c o n t a i n e d 75 t o 85% c o a r s e f r a g m e n t s , had h i g h t r a c e element c o n c e n t r a t i o n s , and l a c k e d N and a v a i l a b l e P. A c c o r d i n g t o schemes f o r r a t i n g t h e q u a l i t y o f r o o t i n g media, t h e h i g h c o a r s e fragment c o n t e n t makes w a s t e r o c k an u n s u i t a b l e o r p o o r s u b s t r a t e . However t h e c o a r s e fragment c o n t e n t o f w a s t e r o c k was comparable t o t h a t o f c o l l u v i a l s o i l s i n t h e K i t s a u l t r e g i o n . As most o f t h e m i n e s i t e was o r i g i n a l l y c o v e r e d i n c o l l u v i u m , a h i g h c o a r s e fragment c o n t e n t w i l l t h e r e f o r e n o t compromise t h e p r o v i n c i a l r e c l a m a t i o n g u i d e l i n e s t h a t m i n e s i t e s s h o u l d be r e s t o r e d t o t h e i r p r e -m i n i n g p r o d u c t i v i t y . R e s e a r c h on d i f f e r e n t d i s t u r b e d s u b s t r a t e s on Vancouver I s l a n d , showed t h a t t h e l a r g e r t h e a r e a d i s t u r b e d t h e s l o w e r was n a t u r a l p l a n t i n v a s i o n , and t h a t t h e c o m p o s i t i o n o f 4 9 s p e c i e s a r r i v i n g r e f l e c t e d t h e c o m p o s i t i o n o f t h e a d j a c e n t v e g e t a t i o n . Most o f t h e r e s e a r c h done i n B.C. has been i n e s t a b l i s h i n g agronomic c o v e r s . N a t u r a l p l a n t i n v a s i o n o f t h e g r a s s \ l e g u m e c o v e r s was g r e a t e s t i n a r e a s w i t h h i g h p r e c i p i t a t i o n . R e s e a r c h e r s have n o t e d changes i n mine w a s t e s w i t h t i m e and as a r e s u l t o f p l a n t growth. P h y s i c a l changes i n c l u d e d d e c r e a s e s i n b u l k d e n s i t y and c o a r s e fragment c o n t e n t , and c l a y movement. Changes i n s o i l c h e m i c a l p r o p e r t i e s i n c l u d e d i n c r e a s e d o r g a n i c m a t t e r , N, and a v a i l a b l e P, and d e c r e a s e s i n pH and c a r b o n a t e m i n e r a l s . D e c r e a s e s i n pH were a s s o c i a t e d w i t h t h e r e l e a s e o f K and t r a c e e l e m e n t s . The most r e l e v a n t s t u d i e s o f n a t u r a l p l a n t and s o i l development t o K i t s a u l t were t h o s e c a r r i e d o u t on r e c e n t l y e xposed m o r a i n e s i n S.E. A l a s k a . The sequence o f p l a n t s u c c e s s i o n on n o n - c a l c a r e o u s m o r a i n e s was S i t k a a l d e r , S i t k a s p r u c e , and w e s t e r n hemlock. I f t h e m o r a i n e s were c a l c a r e o u s , t h e f i r s t s p e c i e s t o i n v a d e was d r y a s , w h i c h i n t u r n a c c e l e r a t e d t h e i n v a s i o n o f a l d e r . The i n i t i a l s o i l changes ( e . g . , d e c r e a s e d b u l k d e n s i t y , pH, and c a l c i t e ) were s i m i l a r t o t h o s e o b s e r v e d on mine w a s t e s . The main f a c t o r s c o n t r o l l i n g p l a n t and s o i l development on t h e m o r a i n e s were t h e a d d i t i o n s o f l i t t e r and N, most o f w h i c h were added by a l d e r . A f t e r 400 y e a r s , t h e s o i l s on t h e m o r a i n e s d e v e l o p e d p o d z o l i c B f h o r i z o n s . S t u d i e s o f mature s o i l s , i n a r e a s w i t h s i m i l a r s o i l f o r m i n g f a c t o r s t o K i t s a u l t , f o u n d t h a t p o d z o l s d e v e l o p e d on a l l w e l l d r a i n e d p a r e n t m a t e r i a l s . I n 5 0 t h e s e s o i l s , r o o t i n g was c o n c e n t r a t e d i n t h e t h i c k , a c i d l i t t e r l a y e r . 51 3. MATERIALS AND METHODS 3.1 D e s c r i p t i o n o f Study s i t e s 3.1.1 S o i l R e s o u r c e s Most o f t h e s o i l samples came from t h e t e r r a c e d w a s t e r o c k dumps. The l o c a t i o n o f t h e s i t e s sampled i s shown i n F i g u r e 1.1. Sample s i t e s were chosen t o show t h e e f f e c t s o f a number o f f a c t o r s i n c l u d i n g r o c k t y p e , s l o p e s v s benches, t i m e s i n c e dump c o n s t r u c t i o n , and n a t u r a l p l a n t i n v a s i o n ( T a b l e s 1.1). A g e n e r a l d e s c r i p t i o n o f each o f t h e dumps sampled i s g i v e n i n T a b l e 1.2. Much o f t h e s a m p l i n g was c a r r i e d o u t i n 1980 d u r i n g t h e p e r i o d o f mine development p r i o r t o t h e mine r e - o p e n i n g . The s i t e s s e l e c t e d had n o t been d i s t u r b e d s i n c e t h e mine c l o s e d i n 1972. The c h o i c e o f s i t e s was l i m i t e d t o two t e r r a c e d dumps, t h e Sou t h E a s t Lower (SEL) and t h e Low Grade Ore (LG) dumps, because much o f t h e w a s t e r o c k mined from 1965 t o 1972 was s p r e a d t h i n l y o v e r n a t u r a l s l o p e s o r had been u s e d as r o a d f i l l . Most o f t h e s a m p l i n g was c a r r i e d o u t on t h e LG dump because more e x t e n s i v e n a t u r a l p l a n t i n v a s i o n had o c c u r r e d t h e r e and i t was t h e l o c a t i o n o f s e v e r a l f i e l d t r i a l s . The LG c o n t a i n e d more m o l y b d e n i t e b u t o t h e r w i s e was s i m i l a r t o a " t y p i c a l " w a s t e r o c k dump. R e c e n t l y exposed w a s t e r o c k on t h e P a t s y (WR) and C l a r y (AR) dumps were sampled i n 1982 ( T a b l e 1.2), on s u r f a c e s u s e d f o r t h e 82.1 and 82.4 t r i a l . S a m p l i n g was c a r r i e d o u t soon a f t e r t h e dumps were b u i l t and i m m e d i a t e l y p r i o r t o LEGEND F i g u r e 1.1 A s c h e m a t i c d i a g r a m o f t l i e K i t s a u l t m i n e s h o w i n g t h e l o c a t i o n o f s i t e s e x a m i n e d i n t h i s s t u d y . Table 1.1 Surfaces sampled and number of samples analysed for untreated wasterock. Number of Samples Analysed Abbreviation Used in Text Dump Lithology Topography Cover Date Constructed Date Sampled For % < 2 mm For other physical analyses For Chemical Analyses SEL.HN South East Lower hornfels bench none pre-1973 1980 4 4 3 SELPO.U potassic bench none pre-1973 1980 3 3 . 3 SEL.PO.V annual species pre-1973 1*980 5 5 5 LG.U.B Low Grade Ore potassic bench none or annual species pre-1973 1980 6 6 6 LG.U.S slope none pre-1973 1980 9 9 9 LG.V bench perennial species pre-1973 1980 7 7 7 WR.82 Patsy potassic bench none 1982 1982 28 4 4 WR.84 1984 8 - -AR.82 Clary incompetent bench' none 1982 1982 8 - 4 4 AR.84 1984 25 _ 54 T a b l e 1.2 D e s c r i p t i o n s o f t h e w a s t e r o c k dumps and t h e o v e r b u r d e n sampled i n t h i s s t u d y . WASTEROCK DUMPS SEL: s o u t h e a s t l o w e r dump; w a s t e r o c k f i l l s b ottom o f v a l l e y , i n t e r s e c t i n g P a t s y Creek on west s i d e ; b u i l t p r i o r t o 1972; b u r i e d i n 1981, LG: low gr a d e o r e dump; l a r g e p l a t e a u n o r t h o f p i t ; b u i l t p r i o r t o 1972; s i t e o f f i e l d t r i a l s 70.1, 70.3, 75.1 and 77.1; u n t r e a t e d a r e a s p r e s e n t l y used t o s t o r e m a c h i n e r y and t o o l s , . WR: P a t s y dump; s e r i e s o f t e r r a c e s s o u t h e a s t o f p i t ; b u i l t from 1981 t o 1982; s i t e o f f i e l d t r i a l s 81.1, 81.2, 81.3, 82.1 and 82.2, AR: C l a r y dump: a s e r i e s o f t e r r a c e s n o r t h o f p i t ; a t p o i n t sampled, a s i n g l e , l a r g e t e r r a c e , t h e bench o f w h i c h s e r v e s as a r o a d t o t h e C l a r y dump complex; b u i l t i n 1982; s i t e o f f i e l d t r i a l 82.4. OVERBURDEN OB.59 594 Bench: o v e r b u r d e n t e s t e d i n T r i a l 82.1; use d and sampled i m m e d i a t e l y a f t e r i t was s t r i p p e d ; a w e l l d r a i n e d , m i x t u r e o f c o l l u v i u m , t i l l , and f r a c t u r e d b e d r o c k . OB.SH Spy H i l l : o v e r b u r d e n t e s t e d i n T r i a l 82.1; m a t e r i a l from t h e Spy H i l l s t o c k p i l e ; s t r i p p e d from a w a t e r l o g g e d d e p r e s s i o n i n 1981. 55 a p p l y i n g t r i a l amendments. The P a t s y Dump was c o m p r i s e d o f " p o t a s s i c " r o c k , t h e most p e r v a s i v e t y p e o f w a s t e r o c k . When i t was re s a m p l e d i n 1984, samples were t a k e n from rows between t h e p l o t s . As i n 1982, s a m p l i n g was r e s t r i c t e d t o t h e t e r r a c e bench. The s l o p e s o f t h e P a t s y Dump were a l m o s t t o t a l l y d e v o i d o f f i n e s . The 82.4 t r i a l on t h e C l a r y Dump was l o c a t e d on a v e n e e r o f " i n c o m p e t e n t " w a s t e r o c k . T h i s m a t e r i a l had been pushed o n t o t h e s l o p e i n 1982, j u s t p r i o r t o s a m p l i n g . I n . 1982, u n s t a b l e f o o t i n g l i m i t e d s a m p l i n g t o t h e upper 10% o f t h e s l o p e . I n 1984, e x t e n s i v e s a m p l i n g was c a r r i e d o u t a l o n g 5 t r a n s e c t s from c r e s t t o t o e . Samples were c o l l e c t e d e v e r y 20 m e t r e s . The 10% o f t h e s l o p e l a c k i n g < 2 mm m a t e r i a l was n o t sampled. The t r e a t m e n t s sampled and t h e number o f samples a n a l y s e d f o r t h e f i e l d t r i a l s a r e shown i n T a b l e 1.3. A l l t h e s a m p l i n g was c a r r i e d o u t i n 1980. L i k e t h e u n t r e a t e d s l o p e b e s i d e i t (LG.US), s a m p l i n g on t h e s l o p e t r i a l 75.1 was l i m i t e d t o t h e upper 8 m e t r e s , t h e o n l y p o r t i o n o f t h e s l o p e c o n t a i n i n g < 2 mm p a r t i c l e s . W i t h i n d e s i g n a t e d a r e a s on t h e f i e l d t r i a l s and t h e u n t r e a t e d dumps, t h e s e l e c t i o n o f sample s i t e s was made randomly. E x c e p t i o n s t o t h i s were t h e v e g e t a t e d s i t e s on t h e SEL dump (SEL.PO.V), w h i c h were so few t h a t t h e y were a l l sampled. The o t h e r e x c e p t i o n was when p l o t s had t o be s h i f t e d t o a v o i d l a r g e r o c k s . T h i s happened about 20% o f t h e t i m e . 56 Overburden samples were t a k e n from t h e two m a t e r i a l s t e s t e d i n t h e P a t s y Dump t r i a l 82.1. D e s c r i p t i o n s o f each a r e g i v e n i n T a b l e 1.2. 3.1.2 V e g e t a t i o n A summary o f t h e s i t e s where p l a n t g r o w t h was s t u d i e d i s g i v e n i n T a b l e 1.4. I n f o r m a t i o n on n a t u r a l p l a n t i n v a s i o n was c o l l e c t e d from T r i a l 70.1 and from u n t r e a t e d s u r f a c e s around t h e mine. Most o f t h e v e g e t a t i o n d a t a was c o l l e c t e d from f i e l d t r i a l s . T r i a l s were named a c c o r d i n g t o t h e y e a r i n w h i c h t h e y were e s t a b l i s h e d . T r i a l s e s t a b l i s h e d p r i o r t o 1980 were b u i l t by Dr. J.V. T h i r g o o d ( P r i c e , 1982). D e t a i l e d d e s c r i p t i o n s o f each t r i a l , i n c l u d i n g o b j e c t i v e s , e x p e r i m e n t a l d e s i g n , m a t e r i a l s , p l o t p r e p a r a t i o n , and m o n i t o r i n g a r e g i v e n i n Appendix A. The l o c a t i o n o f each t r i a l i s shown i n F i g u r e 1. L a t i n names o f agronomic s p e c i e s t e s t e d a t K i t s a u l t a r e g i v e n i n T a b l e 1.5. The components o f seed mixes a p p l i e d on t h e bench and s l o p e t r i a l s and t h e r a t e s a t w h i c h f e r t i l i z e r was a p p l i e d i n f i e l d t r i a l s a r e c o m p i l e d i n T a b l e s 1.6,1.7, and 1.8. The r e a d e r may want t o r e f e r t o i n f o r m a t i o n i n T a b l e s 1.4 t o 1.8 when r e a d i n g t h e r e s u l t s and t h u s s h o u l d n o t e t h e i r l o c a t i o n . 3.2 F o l i a g e and S o i l S a m p l i n g A 900 cm 2 q u a d r a n t (30 cm x 30 cm) was used t o d e l i n e a t e t h e b o u n d a r i e s o f each f o l i a g e sample. B e f o r e 57 Table 1.3 Treatments sampled and number of samples analysed for the field trials. , Number of Samples Abbreviation Trial Topography Surface * * Vegetation Seed Mix * * * Soil Foliar Used in Text Treatment Analyses Chemistry 70R 70PF 70P1 70P5 70P6 70F1 70F5 70F6 70AI 75.1 77.1 70.1 bench 75.1 slope 77.1 bench none peat peat (+ fertilizer) fertil izer fertilizer fertilizer none grass and 1,5 & 6 legume grass and 1,5 & 6 legume mainly 1 grass mainly 5 legume mainly 6 grass mainly 1 grass mainly 5 legume mainly 6 grass annual grass grass and A,B,C & D legume Sitka alder 12 3 17 4* 12 * : for % < 2 mm only * " : fertilizer rate listed in Table 8 * * * : seed mixes described in Tables 6 (mixes 1,5,6) and 7 (mixes A,B,C,D) * * * * : Although the original trial plan stated that 70PF was fertilized while 70P was not, the high P and strong plant growth indicate that it was the 70P section which was fertilized. 58 Table 1.4 A list of the trials testing plant growth. Topography Plant Species Trio/ Treatments Tested Bench Agronomic 70. T 7 seed mixes on 4 surface covers 82.1 4 seed mixes and 5 surface covers Bench Woody 70.3 conifer species with treatments applied in Trial 70.1 77.1 Sitka alder 82.1 . Sitka alder and lodgepole pine on 82.1 treatments Bench Natural Plant Invasion none 70.1 treatments applied in Trial 70.1 Slope Agronomic 75.1 4 seed mixes 81.1 1 seed mix on 4 overburden depths 82.4 incompetent wasterock * * Treatments described in detail in Appendix A, for seed mix composition and fertilizer rate refer to Tables 6, 7 and 8 59 T a b l e 1.5 The L a t i n names o f agronomic s p e c i e s t e s t e d a t K i t s a u l t . L a t i n Name Common Name G r a s s e s Agrostis alba L. Alopecurus arundinaceus P o i r . Dactyl is glomerata L. Deschampsia caespitosa (L.) Beauv. Festuca ovina L. Festuca rubra v a r . cdmmunata L. Festuca rubra v a r . r u b r a L. Lolium multifolium L. Lolium perenne L. Phalaris arundinacea L. Phleum pratense L. Poa compressa L. Poa pratensis L. r e d t o p c r e e p i n g f o x t a i l o r c h a r d g r a s s t u f t e d h a i r g r a s s h a r d f e s c u e chewings f e s c u e r e d f e s c u e a n n u a l r y e g r a s s p e r e n n i a l r y e g r a s s r e e d c a n a r y g r a s s t i m o t h y Canada b l u e g r a s s K e n t u c k y b l u e g r a s s Legumes Astragalus cicer L. L o t u s corniculatus L. Medicago sativa L. Onobrychis viciaefolia S c o p o l i Trifolium hybridum L. Trifolium pratense L. Trifolium repens L. m i l k v e t c h b i r d s f o o t t r e f o i l a l f a l f a common s a i n f o i n a l s i k e c l o v e r r e d c l o v e r w h i t e c l o v e r 60 T a b l e 1.6 Seed mixes a p p l i e d on t h e bench t r i a l s , 70.1 - #1 70.1 - #5 91.5 p e r e n n i a l r y e g r a s s 61.0 s a i n f o i n 61.0 r e d f e s c u e 61.0 b i r d s f o o t t r e f o i l 61.0 chewings f e s c u e 122.0 kg/ha 61.0 K e n t u c k y b l u e g r a s s 15.3 , r e d t o p 15.3 w h i t e c l o v e r 305.0 kg/ha 70.1 - #6 81.1 bench 65.4 t i m o t h y 5.0 p e r e n n i a l r y e g r a s s 43.8 p e r e n n i a l r y e g r a s s 20.0 r e d f e s c u e 65.4 h a r d f e s c u e 10.0 w h i t e c l o v e r 21.8 r e d t o p 25.0 b i r d s f o o t t r e f o i l 21.8 a l s i k e c l o v e r 5.0 r e d t o p 218.0 kg/ha 65.0 kg/ha 82.1 - AG 82.1 - L 50.0 a n n u a l r y e g r a s s 35.8 b i r d s f o o t t r e f o i l 35.8 a l s i k e c l o v e r 35.8 w h i t e c l o v e r 107.6 kg/ha 82.1 - GL 82.1 - EC 5.0 p e r e n n i a l r y e g r a s s 20.0 p e r e n n i a l r y e g r a s s 5.0 o r c h a r d g r a s s 30.0 r e d f e s c u e 5.0 r e d t o p 20.0 r e d t o p 5.0 c r e e p i n g f o x t a i l 20.0 o r c h a r d g r a s s 35.8 b i r d s f o o t t r e f o i l 20.0 t u f t e d h a i r g r a s s 35.8 w h i t e c l o v e r 100.0 kg/ha 91.6 kg/ha 61 T a b l e 1.7 Seed mixes a p p l i e d on t h e s l o p e t r i a l s . 75.1 - A 75.1 - B 9. 3 r e d t o p 16. 8 a l f a l f a 9. 3 r e d f e s c u e 16. 8 b i r d s f o o t t r e f o i l 9. 3 t i m o t h y 16. 8 s a i n f o i n 9. 3 Canada b l u e g r a s s 16. 8 w h i t e c l o v e r 9. 3 o r c h a r d g r a s s 16. 8 a l s i k e c l o v e r 9. 3 p e r e n n i a l r y e g r a s s 84 kg/ha 56 kg/ha 75.1 - C 75.1 - D 12. 6 t i m o t h y 12. 6 p e r e n n i a l r y e g r a s s 12. 6 Canada b l u e g r a s s 12. 6 o r c h a r d g r a s s 8. 4 r e d t o p 16. 8 a l f a l f a 16. 8 b i r d s f o o t t r e f o i l 16. 8 w h i t e c l o v e r 21. 0 s a i n f o i n 16. 8 m i l k v e t c h 12. 6 a l s i k e c l o v e r 84 kg/ha 84 kg/ha 81.1 10.0 p e r e n n i a l r y e g r a s s 40.0 r e d f e s c u e 20.0 w h i t e c l o v e r 50.0 b i r d s f o o t t r e f o i l 10.0 r e d t o p 130 kg/ha 62 Table 1.8 The rate at which fertilizer was applied in the field trials Trial Surface Rate Analysis N P K (kg/ha) (kg/ha) Bench -70.1 WR & O B 610 13-16-10 79 43 51 -82.1 . WR 417 12-39-12 50 71 42 -82.1 OB '1 208 12-39-12 25 36 21 jpe -75.1 WR 373 12-6-10 45 10 31 -81.1 WR 625 12-39-12 75 107 63 -81.1 OB '2 313 12-39-12 38 53 31 OB : overburden WR : wasterock * 1 : also applied 69 kg/ha of lime *2 : also applied 103 kg/ha of lime 63 s a m p l i n g t h e p e r c e n t a g e c o v e r o f p l a n t s p e c i e s , moss, l i t t e r , f i n e s , and r o c k were v i s u a l l y e s t i m a t e d . The p i n i n t e r c e p t i o n t e c h n i q u e was used t o check t h e a c c u r a c y o f t h e v i s u a l c o v e r e s t i m a t e s . V i s u a l e s t i m a t e s were w i t h i n 10% o f t h e p i n d a t a . Where t h e f o l i a g e was sampled, a l l above ground m a t e r i a l w i t h i n t h e 900 cm 2 q u a d r a n t was c l i p p e d . A 225 cm 2 (15 cm x 15 cm) q u a d r a n t p l a c e d i n t h e c e n t e r o f each sample s i t e was used as an a r e a l g u i d e f o r d i g g i n g s o i l s a mples. To measure t h e volume o f m a t e r i a l removed, t h e s pace c r e a t e d was l i n e d w i t h a p l a s t i c bag. The h o l e was t h e n f i l l e d w i t h m a r b l e s (1.5 cm d i a m e t e r ) and t h e volume o f m a r b l e s d e t e r m i n e d i n a v o l u m e t r i c c y l i n d e r . M a r b l e s were used i n s t e a d o f w a t e r o r sand because i f , as o f t e n happened, t h e p l a s t i c was p u n c t u r e d by t h e s h a r p r o c k s , t h e m a t e r i a l below was n o t i r r e v o c a b l y c o n t a m i n a t e d . The dump s u r f a c e was v e r y rough and t h u s t h e uneven s u r f a c e o f t h e m a r b l e s d i d n o t compromise t h e a c c u r a c y o f t h e v o l u m e t r i c measurement. On s u r f a c e s abandoned p r i o r t o 1973 (sampled i n 1980), s e p a r a t e samples from t h e 0-5 and 5-10 cm d e p t h s were e x t r a c t e d . F o r s u r f a c e s dumped i n 1982 (sampled i n 1982 and 1984), one 0-10 cm sample was c o l l e c t e d . I n b o t h c a s e s l i t t e r , p e a t , and r o o t s were sampled a l o n g w i t h t h e m i n e r a l m a t e r i a l . The d e p t h o f t h e s u r f a c e o r g a n i c l a y e r was measured a f t e r sample e x t r a c t i o n . 64 3.3 L a b o r a t o r y A n a l y s e si 3.3.1 S o i l Samples S o i l samples were o v e n - d r i e d a t 80°C f o r 24 h o u r s and t h e n r e w e i g h e d t o d e t e r m i n e t o t a l d r y w e i g h t , w h i c h was used t o c a l c u l a t e t h e b u l k d e n s i t y . Next t h e sample was s e p a r a t e d i n t o > 12.7 mm, 12.7 t o 2 mm and < 2 mm f r a c t i o n s by s i e v i n g f o r 3 m i n u t e s on a r o t o - t a p m e c h a n i c a l s i e v e r . Where p r i m a r y p a r t i c l e s adhered t o one a n o t h e r , clumps were b r o k e n up u s i n g a r o l l i n g p i n . The samples were t h e n r e s i e v e d by hand. T h i s was alw a y s n e c e s s a r y when samples c o n t a i n e d p e a t . A f t e r s i e v i n g , each f r a c t i o n was weighed and t h e < 2 mm f r a c t i o n s were s t o r e d i n p l a s t i c c a r t o n s . pH and a v a i l a b l e P a s s a y s were done on t h e < 2 mm m a t e r i a l . F o r t o t a l C and N a n a l y s i s , a p o r t i o n o f each sample was ground t o < 50 um u s i n g a m o r t a r and p e s t l e . P r i o r t o p a r t i c l e s i z e a n a l y s i s , o r g a n i c m a t t e r was removed w i t h NaOCl, c a r b o n a t e s and s o l u b l e s a l t s were removed w i t h Na a c e t a t e , and s e s g u i o x i d e s were removed w i t h c i t r a t e d i t h i o n a t e b i c a r b o n a t e , a c c o r d i n g t o t h e methods o f L a v k u l i c h and Wiens (1970), and Kunze (1965). P a r t i c l e s i z e was t h e n d e t e r m i n e d by t h e hydrometer method (Day, 1965). pH was measured u s i n g a 1:2 mix o f s o i l and 0.01 M C a C l 2 (Peech, 1965). T o t a l C was measured on a Leco d r y c o m b u s t i o n a n a l y s e r . T o t a l N was e x t r a c t e d by wet ( b l o c k ) d i g e s t i o n (Bremner, 1965). A v a i l a b l e phosphorus was e x t r a c t e d u s i n g t h e Br a y P I method ( O l s e n & Dean, 1965). N 65 and P e x t r a c t s were a n a l y z e d c o l o r i m e t r i c a l l y w i t h a T e c h n i c o n A u t o - A n a l y s e r I I . 3.3.2 P l a n t Samples I m m e d i a t e l y a f t e r s a m p l i n g , f o l i a g e samples were oven d r i e d a t 80°C f o r 24 h o u r s , and t h e n r e w e i g h e d t o d e t e r m i n e t h e d r y w e i g h t . T o t a l C was measured on a Leco d r y c o m b u s t i o n a n a l y s e r . T o t a l N, P, K, Ca, and Mg were d e t e r m i n e d u s i n g P a r k i n s o n and A l l e n ' s (1975) wet o x i d a t i o n method. E x t r a c t K, Ca, and Mg were measured by f l a m e a t o m i c a b s o r p t i o n s p e c t r o s c o p y . N and P were measured c o l o r i m e t r i c a l l y w i t h a T e c h n i c o n A u t o - A n a l y s e r I I . 3.4 D a t a A n a l y s i s 3.4.1 S o i l R e s o u r c e s D e s c r i p t i v e s t a t i s t i c s (mean, s t a n d a r d d e v i a t i o n , c o e f f i c i e n t o f v a r i a n c e , minimum and maximum) were c a l c u l a t e d f o r each group, sample s i t e x d e p t h c o m b i n a t i o n . The Mann Whitney U t e s t was used t o d e t e r m i n e whether d i f f e r e n c e s among groups were s i g n i f i c a n t . The W i l c o x o n m a t c h e d - p a i r s s i g n e d - r a n k s t e s t was used t o d e t e r m i n e whether d i f f e r e n c e s between d e p t h s were s i g n i f i c a n t . B oth t h e Mann Whitney and t h e W i l c o x o n t e s t s a r e n o n - p a r a m e t r i c t e c h n i q u e s . These t e s t s were used because t h e d a t a d i d n o t meet some o f t h e r e q u i r e m e n t s ( e . g . , homogeneous v a r i a n c e , normal d i s t r i b u t i o n ) r e q u i r e d f o r p a r a m e t r i c t e c h n i q u e s ( e . g . , T. t e s t ) . C o r r e l a t i o n s between v a r i a b l e s were r u n : 66 s e p a r a t e l y on t h e samples from t h e f i e l d t r i a l s and on t h e samples from t h e u n t r e a t e d dumps. I n some c a s e s , groups w h i c h were 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 were lumped t o g e t h e r p r i o r t o i n t e r p r e t a t i o n . F o r example, u n v e g e t a t e d s i t e s , s i t e s c o l o n i z e d by a n n u a l s p e c i e s , and s i t e s i n h a b i t e d by p e r e n n i a l s p e c i e s were sampled on t h e LG dump. Subsequent s o i l a n a l y s i s showed no d i f f e r e n c e i n t h e p h y s i c a l a n d " c h e m i c a l p r o p e r t i e s between t h e u n v e g e t a t e d p l o t s and p l o t s c o l o n i z e d by a n n u a l p l a n t . -s p e c i e s , so t h e s e two groups were combined i n t o one, LG.U.B. The two o t h e r c a s e s i n w h i c h groups were combined were on t h e f i e l d t r i a l s . I n T r i a l s 70.1 and 75.1, t h e r e were no s i g n i f i c a n t d i f f e r e n c e s i n t h e s o i l p r o p e r t i e s i n a r e a s sown w i t h d i f f e r e n t s eed m i x e s . So w i t h i n each s u r f a c e < t r e a t m e n t , p l o t s from a r e a s sown w i t h d i f f e r e n t seed mixes were combined i n t o one group. 67 4. RESULTS AND DISCUSSION 4.1 S o i l R e s o u r c e s 4.1.1 U n t r e a t e d Wasterock 4.1.1.1 P h y s i c a l P r o p e r t i e s S u r f a c e c o n d i t i o n s f o r t h e samples c o l l e c t e d on t h e abandoned w a s t e r o c k dumps a r e shown i n A p p e n d i x A. A r e a x. de p t h means and s t a n d a r d d e v i a t i o n s a r e shown i n T a b l e 1.9. The t h i n d e p t h o f l i t t e r i n d i c a t e s t h a t t h e p l a n t g r o w t h has n o t been v e r y v i g o r o u s . Of t h e d i f f e r e n t measurements o f s u r f a c e c o v e r , moss was t h e most s t r o n g l y c o r r e l a t e d w i t h t h e d e p t h o f l i t t e r (r=0.76). A d d i n g e i t h e r t h e v a s c u l a r p l a n t o r t h e l i t t e r c o v e r t o t h e moss c o v e r r e d u c e d 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 . I t was n o t c l e a r whether moss growth was s t i m u l a t e d by p r e v i o u s o r g a n i c a d d i t i o n s from v a s c u l a r p l a n t s o r i f t h e moss i t s e l f was t h e p r i m a r y s o u r c e o f t h e s u r f a c e o r g a n i c l a y e r . P r o b a b l y b o t h s c e n e r i o s o c c u r r e d . S o i l p h y s i c a l d a t a f o r i n d i v i d u a l samples f o r each g r o u p o f samples c o l l e c t e d from t h e u n t r e a t e d dumps a r e t a b u l a t e d i n App e n d i x B. Area' x d e p t h means and s t a n d a r d d e v i a t i o n s f o r % < 2 mm, wt. < 2 mm/m3 and b u l k d e n s i t y a r e l i s t e d i n T a b l e 1.10. The u n t r e a t e d a r e a s showed c o n s i d e r a b l e v a r i a t i o n i n t h e i r a v e r a g e % < 2mm, wt. < 2 mm/m3, and b u l k d e n s i t i e s . Many d f t h e d i f f e r e n c e s among 68 Table 1.9 Surface conditions in 1980 on areas of untreated wasterock and overburden abandoned in 1972. Site % Moss % Vascular Plant % Moss + Litter SELHN SELPO.U LG.U.S LG.U.B SEL.PO.V LG.V 0 (0) a 0 (0) a 5 (6) b 5(2) b 23 (41) be 35 (30) c 0 (0) a 0 (0) a 0 (0) a 3 (3) b 9 (4) c 26 (28) c 1 (1) ab 0 (0) a 6 (6) be 8 (5) c 31 (56) bed 40 (34) d 70.OB 83 (13) d % Moss + Vascular Plant 47 (14) d Litter (cm) 116 (9) e SEL.HN SELPO.U. LG.U.S LG.U.B SELPO.V LG.V 0 (0) a 0 (0) a 5 (6) b 8 (3) be 32 (44) c 61 (34) d 0.0 (0.0) a 0.0 (0.0) a 0.2 (0.3) ab 0.2 (0.4) ab 0.7 (0.7) ab 0.8 (0.8) b 70.OB 130 (23) e 6.6 (4.5) c % : % cover 0 (0) : mean (std dev) cm : depth means followed by the same letter were not significantly different at p = 0.5 69 Table 1.10 Soil physical propertii %<2mm Site Depth SEL.HN 0-5cm 11 (4) a SELHN 5-10cm 12 (4) a LG.U.B 5-10cm 19 (5) b WR.84 0-10cm 19 (5) b LG.U.B 0-5cm 21 (6) be LG.U.S 0-5cm 23 (8) bed WR.82 0-10cm 24 (9) cde SELPO 0-5cm 25 (7) cde SELPO 5-10cm 25 (10) cde LG.U.S 5-10cm 26 (6) cde AR.84 0-10cm 32 03) ef AR.82 0-10cm 35 (10) f LG.V 5-10cm 36 (9) f LG.V 0-5cm 37 (11) f 0 (0) : mean (standard deviation) means followed by the same letter were of the untreated wasterock clumps. <2mm/m3 Bulk Density (kg/m3) (1000 kg/m-3) 198 (83) ab 1.87 (.23) be 266 (63) be 2.21 (.23) a 327 (58) cd 1.76 (.29) ecd 379 (124) def 1.81 (.24) bed 415 (149) defg 1.80 (.17) bed 452 (194) efg 2.08 (.44) ab 423 (112) efg 1.76 (.32) ecd 483 (173) fgh 1.95 (.28) a be 456 (102) efg 1.75 (.31) cd 644 (191) h 1.82 (.12) be 533 (153) gh 1.55 (.48) ed 541 (133) gh 1.52 (.30) ed not significantly different at p = 0.5 Table 1.11 The probability that differences exist between the physical properties the 0-5 and the 5-10 cm depths of the untreated wasterock dumps. Site % <2mm <2mm/m3 Bulk Density SEL.HN 0.23 0.07 0.07 SELPO 0.47 0.20 0.03 LG.U.S 0.34 0.30 0.38 LG.U.B 0.22 0.07 0.26 LG.V 0.43 0.43 0.20 * : significant at the 0.05 level of probability 70 a r e a s were s t a t i s t i c a l l y s i g n i f i c a n t . L i k e o t h e r Cu-Mo p o r p h y r y mines i n B.C., i n c o m p a r i s o n w i t h a g r i c u l t u r a l s o i l s , t h e % < 2 mm o f t h e w a s t e r o c k was v e r y low and t h e b u l k d e n s i t y was v e r y h i g h . The range i n % < 2 mm and b u l k d e n s i t y f o r t h e p o t a s s i c w a s t e r o c k was s i m i l a r t o w a s t e r o c k o f s i m i l a r l i t h o l o g y a t t h e Endako, L o r n e x and Bethlehem mines, w h i l e t h e p r o p o r t i o n o f s o i l s i z e d p a r t i c l e s i n t h e f i n e r g r a i n e d h o r n f e l s w a s t e r o c k p a r a l l e l e d s i m i l a r low v a l u e s f o r f i n e g r a i n e d v o l c a n i c r o c k a t t h e S i m i l k a m e e n mine (Murray 1977). A c c o r d i n g t o t h e W i l c o x o n T e s 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 between t h e 0-5 cm and t h e 5-10 cm s o i l p h y s i c a l d a t a was f o r SEL.PO b u l k . d e n s i t y ( T a b l e 1.11). However, i t c a n n o t be i n f e r r e d t h a t sample s i t e s were p h y s i c a l l y homogeneous. The h i g h e s t c o r r e l a t i o n c o e f f i c i e n t between p h y s i c a l p r o p e r t i e s a t d i f f e r e n t d e p t h s was o n l y 0.58 ( T a b l e 1.12). T h i s was f o r t h e % < 2mm. Each i n d i v i d u a l s i t e was a h e t e r o g e n e o u s mix o f c o a r s e and f i n e f r a g m e n t s , t h e , p h y s i c a l p r o p e r t i e s o f w h i c h depended i n p a r t on whether l a r g e s t o n e s were i n t e r c e p t e d . Comparing t h e a v e r a g e d a t a f o r t h e u n t r e a t e d a r e a s , t h e f o l l o w i n g r e l a t i o n s h i p between % < 2 mm and r o c k t y p e was a p p a r e n t . h o r n f e l s < p o t a s s i c < i n c o m p e t e n t 10-13% 19-26% 31-36% W i t h o n l y a few e x c e p t i o n s , d i f f e r e n c e s between a r e a s c o m p r i s e d o f d i f f e r e n t r o c k t y p e s were s i g n i f i c a n t . The 71 Table 1.12 Correlation coefficients for soil physical properties of the untreated wasterock dumps. Bulk % Density <2mm for all depths Bulk Density X %<2mm -.47 <2mm/m3 -.07 0-5 cm vs 0-5 cm Bulk Density %<2mm <2mm/m3 X -.57* .18 - among 0-5, 5-10 and 0-10 cm X samples from unweathered .89* and abandoned sites X .88* - among 0-5 cm samples from abandoned sites 5-10 cm vs 5-10 cm  Bulk Density X %<2mm -.61* X <2mm/m3 -.15 .86* 0-5 cm vs 5-10 cm among 5-10 cm samples from abandoned sites Bulk Density .36 -.34 -.15 - between 0-5 cm and 5-1 %<2mm -.44 .58" .43 sampi es from abandoned <2mm/m3 -.31 .53* .51* sites Bulk Density %<2 mm <2mm/m3 0-5 5-1Q 0-5 5-10 0-5 5-10 % Moss -.57* -.19 .51* .24 .21 .10 % Vascular Plant -.15 -.02 .16 .19 .14 .18 * : % Moss + Litter -.53* -.13 .46 .25 .21 .15 % Moss+Vas.Pl. -.51* -.15 .46 - .28 .22 .16 Litter (cm) - .59' -.43 .52* .45 .22 .21 : > 0.5 72 c o n c l u s i o n t h a t f i n e g r a i n e d h o r n f e l s r o c k (SEL.HN) pr o d u c e s t h e s m a l l e s t % < 2 mm was s u p p o r t e d by t h e d a t a from t h e Spy H i l l o v e r b u r d e n (OB.SH), w h i c h was formed from h o r n f e l s r o c k , and w h i c h a l s o had a v e r y low % < 2 mm. Incompetent (AR) and p o t a s s i c (WR) w a s t e r o c k s u r f a c e s c r e a t e d i n 1982 were sampled t o compare t h e c h a r a c t e r i s t i c s o f t h e s e two r o c k t y p e s . I n b o t h 1982 and 1984, samples o f t h e i n c o m p e t e n t w a s t e r o c k c o n t a i n e d t h e h i g h e s t p r o p o r t i o n o f f i n e s . From 1982 t o 1984, t h e % < 2 mm o f b o t h t h e ...... i n c o m p e t e n t and p o t a s s i c w a s t e r o c k d e c l i n e d . A l o s s o f f i n e r p a r t i c l e s from t h e s u r f a c e can r e s u l t from s u r f a c e movement as a dump s e t t l e s . P o t a s s i c r o c k was t h e most common r o c k t y p e i n t h e waste and most o f t h e a r e a s sampled were c o m p r i s e d o f p o t a s s i c r o c k . D i f f e r e n c e s i n t h e p h y s i c a l c h a r a c t e r i s t i c s o f p o t a s s i c s u r f a c e s (Sel.PO and LG.U) may be a t t r i b u t e d t o l o c a l v a r i a t i o n s i n m a t e r i a l h a n d l i n g and t o l i t h o l o g i c a l d i f f e r e n c e s . The t e r m p o t a s s i c d e s c r i b e s r o c k p r e d o m i n a n t l y c o m p r i s e d o f c o a r s e g r a i n s o f K f e l d s p a r and q u a r t z . W i t h i n t h i s g e n e r a l d e f i n i t i o n , t h e r e can be c o n s i d e r a b l e v a r i a t i o n i n m i n e r a l o g y and g r a i n s i z e . These c h a r a c t e r i s t i c s i n f l u e n c e r o c k competency, w h i c h i n t u r n c a n a f f e c t t h e p h y s i c a l p r o p e r t i e s o f t h e w a s t e r o c k . Bench s i t e s on t h e LG dump s u p p o r t i n g s t r o n g p e r e n n i a l p l a n t g r o w t h (LG.V) c o n t a i n e d t h e h i g h e s t % < 2 mm. P o s s i b l e r e a s o n s f o r t h e h i g h e r % < 2 mm i n c l u d e some form o f s m a l l s c a l e p a r t i c l e s i z e s e g r e g a t i o n o r d e g r a d a t i o n 73 d u r i n g dump c o n s t r u c t i o n o r i n t e n s e w e a t h e r i n g r e s u l t i n g from p l a n t g r o w t h . A l t h o u g h b o t h d e p t h s o f LG.V had a low pH v a l u e s ( T a b l e 1.14), g i v e n t h e l i m i t e d t i m e p e r i o d s i n c e t h e m a t e r i a l was dumped, i t i s u n l i k e l y t h a t p l a n t growth ( e . g . , r o o t growth and o r g a n i c a c i d p r o d u c t i o n ) was t h e p r i m a r y c ause o f t h e d i f f e r e n c e i n p h y s i c a l p r o p e r t i e s . P erhaps t h e b e s t e x p l a n a t i o n f o r t h e h i g h % < 2 mm i n LG.V i s t h a t p e r e n n i a l p l a n t s i n v a d e d a r e a s o f t h e LG dump c o n t a i n i n g p o c k e t s o f in c o m p e t e n t r o c k . W h i l e t h e i n c o m p e t e n t r o c k i s p e r v a s i v e i n o n l y a s m a l l p o r t i o n o f t h e p i t , p o c k e t s o f i t were more w i d e l y d i s s e m i n a t e d . D u r i n g t h e l a s t phase o f m i n i n g (1980 t o 1983), p o c k e t s o f i n c o m p e t e n t m a t e r i a l were found i n o r e w i t h s i m i l a r Mo c o n c e n t r a t i o n t o t h e r o c k s t o r e d i n t h e LG dump. The p r e s e n c e o f in c o m p e t e n t m a t e r i a l would e x p l a i n why LG.V had s i m i l a r < 2 mm c o n t e n t s t o t h e in c o m p e t e n t dump s l o p e (AR.82 and AR.84). The range i n ave r a g e b u l k d e n s i t i e s was c o n s i d e r a b l y l e s s t h a n t h a t f o r % < 2 mm, and a c c o r d i n g t o t h e Mann Whitney U t e s t , t h e b u l k d e n s i t i e s o f 8 o f t h e 12 a r e a x d e p t h c o m b i n a t i o n s were 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 ( T a b l e 1.10). However, t h e s t r o n g e s t c o r r e l a t i o n s between s o i l p h y s i c a l p r o p e r t i e s and d i f f e r e n t c o v e r measurements were f o r t h e 0-5 cm b u l k d e n s i t y w i t h t h e moss c o v e r (r=-0.57) and t h e t h i c k n e s s o f t h e l i t t e r l a y e r ( r = - 0 . 5 9 ) ( T a b l e 1.12). The 0-5 cm % < 2 mm a l s o had i t s s t r o n g e s t c o r r e l a t i o n s w i t h t h e s e two s u r f a c e measures. 74 S o i l p r o p e r t i e s w i t h t h e g r e a t e s t e f f e c t s on b u l k d e n s i t y were o r g a n i c m a t t e r and % < 2 mm. F o r example, LG.V, w h i c h had t h e l a r g e s t % < 2 mm and % o r g a n i c m a t t e r , had t h e l o w e s t b u l k d e n s i t y . SEL.HN, w h i c h had t h e l o w e s t % < 2 mm and c o n t a i n e d v e r y l i t t l e o r g a n i c m a t t e r , had t h e h i g h e s t b u l k d e n s i t y . E x p a n s i o n by r o o t g r o w t h and t h e l o s s o f s o l u b l e components ( e . g . , c a l c i t e ) m i g h t a l s o have c o n t r i b u t e d t o t h e low b u l k d e n s i t y a t LG.V s i t e s , many o f w h i c h were i n h o l l o w s . As e x p e c t e d from i t s h i g h e r % < 2 mm, t h e i n c o m p e t e n t w a s t e r o c k (AR.82) had a l o w e r b u l k d e n s i t y t h a n t h e unweathered p o t a s s i c w a s t e r o c k (WR.82). As a dump s e t t l e s , t h e s u r f a c e b u l k d e n s i t y , s h o u l d i n c r e a s e . However, t h e two r e c e n t l y dumped m a t e r i a l s (WR and AR) had h i g h e r b u l k d e n s i t i e s t h a n m a t e r i a l s w i t h a much l o w e r p r o p o r t i o n o f f i n e s . ' T h i s c o u l d be a r e s u l t o f measurement e r r o r s . B u l k , d e n s i t y d e t e r m i n a t i o n r e q u i r e s measurement o f t h e volume o f m a t e r i a l e x t r a c t e d , and t h i s n e c e s s i t a t e s an e s t i m a t i o n o f t h e o r i g i n a l s u r f a c e h e i g h t . S t o n e y dumps have a v e r y uneven m i c r o t o p o g r a p h y making t h i s v e r y d i f f i c u l t . As t h e unweathered p o t a s s i c s i t e was r i p p e d p r i o r t o s a m p l i n g , i t s s u r f a c e was v e r y rough and i t s b u l k d e n s i t y had a r e l a t i v e l y h i g h s t a n d a r d d e v i a t i o n . Problems e n c o u n t e r e d i n m e a s u r i n g sample volume were compounded on t h e i n c o m p e t e n t s i t e by t h e s t e e p n e s s o f t h e s l o p e and t h e u n s t a b l e c o n d i t i o n s j u s t a f t e r dumping. 75 Perhaps t h e most n o t a b l e f e a t u r e w i t h r e g a r d s t o s o i l t e x t u r e was how s i m i l a r a l l t h e groups were ( T a b l e 1.13). A l l s i t e s c o n t a i n e d v e r y l i t t l e c l a y and a t l e a s t 50% sand, and were c l a s s i f i e d as sandy loams based on t h e i r a verage sand, s i l t and c l a y c o n t e n t s . A few i n d i v i d u a l samples were loamy sands. The o n l y d i s t i n c t t e x t u r a l d i f f e r e n c e among groups was t h a t t h e h o r n f e l s w a s t e r o c k (SEL.HN) c o n t a i n e d more s i l t and c l a y , and l e s s sand t h a n t h e o t h e r m a t e r i a l s . The f i n e r s o i l t e x t u r e o f t h e h o r n f e l s w a s t e r o c k can be a t t r i b u t e d t o t h e f i n e r g r a i n s i z e o f t h e r o c k . No t e x t u r a l d i f f e r e n c e s were e v i d e n t between t h e unweathered i n c o m p e t e n t (AR) and p o t a s s i c (WR) w a s t e r o c k s o r between o t h e r g r o u p s t h a t d i f f e r e d i n % < 2 mm. 76 Table 1.13 Soil texture information for different sites on the untreated wasterock dumps. 0-5 cm or 0-10 cm 5-10 cm # Sand Silt Clay Texture # Sand Silt Clay Te> Site % % % % % • % Average WR.82 4 66 29 5 si. AR.82 4 65 31 5 si. SELHN 3 57 37 6 si. 3 53 36 12 si. SELPO 6 68 23 9 si- 6 68 22 10 si. LGU.B 2 70 18 . 12 si. 2 65 27 9 si. LG.U.S 2 73 21 6 si. 2 73 18 9 si. LG.V 5 70 24 6 si. 5 67 24 9 si. Standard Deviation WR.82 AR.82 2 6 2 7 SELHN SELPO 4 3 5 4 2 3 1 6 6 5 5 4 LG.U.B LG.U.S LG:V 6 9 4 9 6 4 9 3 4 1 6 2 1 5 1 4 4 # : number of samples s.l. : sandy loam 77 4.1.1.2 C h e m i c a l P r o p e r t i e s R e s u l t s from t h e f o u r c h e m i c a l a n a l y s e s (pH, C, N and a v a i l a b l e P) c a r r i e d o u t on t h e < 2 mm f r a c t i o n o f w a s t e r o c k s o i l a r e r e p o r t e d on a w e i g h t p e r w e i g h t (%, ppm) and weight/volume b a s i s . Data f o r i n d i v i d u a l samples can be found i n A p p e n d i x B. The pH d a t a was n o t c o n v e r t e d i n t o H + i o n a c t i v i t y p r i o r t o c a l c u l a t i n g t h e d e s c r i p t i v e s t a t i s t i c s . Thus t h e pH a v e r a g e s r e p o r t e d a r e g e o m e t r i c means. A l l o t h e r means a r e a r i t h m e t i c . D e s p i t e t h e problems e n c o u n t e r e d i n m e a s u r i n g t h e volume o f each sample, t h e v a r i a b i l i t y was n o t i n c r e a s e d when t h e d a t a was t r a n s f o r m e d i n t o t h e p e r m 3 b a s i s . The advantage o f d a t a r e p o r t e d on a weight/volume b a s i s i s t h a t i t a c c o u n t s f o r t h e l a r g e p r o p o r t i o n o f s t o n e s . T h i s i s p a r t i c u l a r l y i m p o r t a n t f o r comparing s o i l i n p u t s s i n c e a l a r g e s t o n e volume may i n c r e a s e t h e c o n c e n t r a t i o n o f t h e added m a t e r i a l i n t h e < 2 mm f r a c t i o n . D i f f e r e n c e s i n y e a r s o f ex p o s u r e ( e . g . , WR.82 v s LG.PO.U), r o c k t y p e ( e . g . , AR.82 v s WR.82, SEL.PO.U v s SEL.HN, and SEL v s LG), v e g e t a t i o n ( e . g . , SEL.PO.U v s SEL.PO.V), and s a m p l i n g d e p t h (0-5 v s 5-10 cm) r e s u l t e d i n s i g n i f i c a n t d i f f e r e n c e s between g r o u p s , as w e l l as a wide range o f ave r a g e v a l u e s ( T a b l e 1.14). The range i n v a l u e s i s a p p r o x i m a t e l y l O x f o r %C, 25x f o r %N, 200x f o r ppm a v a i l a b l e P, and 4000x f o r H i o n a c t i v i t y . The range i n v a l u e s i s s i m i l a r when t h e d a t a i s r e p o r t e d on a w e i g h t / n r 7 8 Table 1.14 Soil chemical properties of the untreated wasterock dumps. Site Depth pH* %c C/m3 (0.1) fg (kg/m3) WR.82 0-1 Ocm 7.6 (0.1) a 1.1 6.2 (1.6) .9 AR.82 0-10cm 7.6 (0.2) a 1.4 (0.7) fg 7.8 (1.9) g SELPO.U 5-10cm 7.7 (0.2) a 0.5 (0.2) bed "2.4 (1.0) cde SEL.PO.U 0-5cm 7.5 (0.2) a 0.5 (0.2) cd 2.4 (1.1) cde SELHN 0-5cm 7.3 (0.0) b 0.8 (0.1) ef 1.3 (0.3) abc LG.U.B 5-10cm 7.1 (0.4) be 0.5 (0.2) cd 1.7 (0.7) cd SELHN 5-10cm 7.1 (0.2) bee 0.9 (0.1) ef 2.3 (0.3) cde SELPO.V 5-1 Ocm 7.0 (0.1) ed 0.4 (0.2) abc 2.2 (1.5) abed LG.U.B 0-5cm 6.5 (0.6) def 0.5 (0.4) cd 1.6 (0-6) cdf SELPO.V 0-5cm 6.4 (0.6) e 0.7 (0.6) def 2.7 (2.3) cde LG.U.S 5-10cm 6.4 (1.2) cdef 0.2 (0.1) a 0.9 (0.4) a LG.U.S 0-5cm 6.2 (1.2) cdef 0.2 (0.1) ab 1.0 (0.6) ab LG.V 5-10cm 4.1 (0.5) g 0.7 (0.2) cde 3.6 (0.7) ef LG.V 0-5cm 4.1 (0.3) g 1.2 (0.7) fg 6.5 (3.4) g Site Depth %N N/m3 availab e P (kg/m3) (ppm) abc WR.82 0-1 Ocm 0.4 (0.1) AR.82 0-1 Ocm 0.5 (0.4) abc SELPO.U 5-10cm 0.004 (0.003) a 0.02 (0.00) a 0.2 (0.0) a SELPO.U 0-5cm 0.008 (0.003) abc 0.03 (0.01 }ab 0.4 (0.0) b SELHN 0-5cm 0.013 (0.002) be 0.02 (0.01) a 1.0 (0.4) cd LG.U.B 5-1 Ocm 0.012 (0.006) be 0.04 (0.02) ab 3.0 (2.7) def SELHN 5-10cm 0.0 n (0.004) abc 0.03 (0.02) ab 1.1 (0.1) d SEL.PO.V 5-10cm 0.007 (0.003) ab 0.03 (0.01 Jab 1.5 (0.9) d LG.U.B 0-5cm 0.020 (0.007) de 0.07 (0.02) c 2.2 (2:0) bcde SEL.PO.V 0-5cm 0.022 (0.018) cdef 0.09 (0.07) cd 3.0 (1.7) efg LG.U.S 5-10cm 0.006 (0:004) ab 0.03 (0.03) ab 6.5 (7.9) dfghi LG.U.S 0-5cm 0.011 (0.008) abed 0.05 (0.04) be 6.2 (7.6) delgr LG.V 5-1 Ocm 0.023 (0.010)ef 0.11 (0.03) d 19.2 (8.1) i k LG.V 0-5cm 0.038 (0.012) f 0.20 (0.08) e 12.4 (6.2) hijk Site Depth available P/m3 C / N xC/xN N /available P g/m3) WR.82 0-1 Ocm 0.2 0.1) a AR.82 0-1 Ocm 0.2 0.1) ab SELPO.U 5-10cm 0.1 0.1) ab 144 72) a 115 206 (142) ab SELPO.U 0-5cm 0.2 0.0) a 76 35) abed 67 192 (77) ab SELHN 0-5cm 0.2 0.0) a 67 11) be 65 147 (50) abc LG.U.B 5-10cm 1.1 1.1) be 48 20) cdef 42 116 (161) a bee SELHN 5-10cm 0.3 0.1) abc 101 41) abd 83 103 (48) abed SELPO.V 5-1 Ocm 0.7 0.3) be 76 43) abcde 64 62 (35) abcde LG.U.B 0-5cm 1.0 1.0) abc 24 11) g 25 463 (949) a SEL.PO.V 0-5cm 1.2 0.8) c 37 16) defg 32 67 (20) bcde LG.U.S 5-10cm 3.5 4.5) cde 64 61) abedef 31 21 (14) LG.U.S 0-5cm 2.9 4.5) cd 29 18) fg 20 36 (22) el LG.V 5- 10cm 9.2 2.2) g 33 4) efg 29 13 (4) g LG.V 0-5cm 7.0 4.2) efg 31 9) efg 32 44 (30) def geometric mean xC/xN : mean %C / mean %N 0 (0) : mean (standard deviation) means followed by the same letter were not significantly different at p = 0.5 79 b a s i s . A l t h o u g h some o f t h e d i f f e r e n c e s were q u i t e l a r g e , i t i s i m p o r t a n t t o remember t h a t o n l y t h e t o p 0-10 cm was sampled. Even w i t h i n t h e t h i n l a y e r sampled, i n many c a s e s , marked changes o n l y o c c u r r e d i n t h e upper 5 cm. On newly exposed g l a c i a l m o r a i n e s i n t h i s e n v i r o n m e n t , U g o l i n i (1967) c o n c l u d e d t h a t most p e d o g e n i c changes r e s u l t e d from t h e a d d i t i o n o f p l a n t r e s i d u e s . P l a n t growth and t h e a d d i t i o n o f p l a n t r e s i d u e s a l s o a ppeared t o be t h e d r i v i n g f o r c e f o r many o f t h e changes o b s e r v e d on t h e newly exposed w a s t e r o c k dumps. There were a number o f s t r o n g c o r r e l a t i o n s between o r g a n i c c o v e r t y p e s and s o i l c h e m i c a l p r o p e r t i e s ( T a b l e 1.15), two o f t h e s t r o n g e s t o f w h i c h were f o r moss c o v e r w i t h t h e 0-5 cm %C (r=0.86) and %N (r=0.82) l e v e l s . T h i s can be e x p l a i n e d b o t h by t h e c o n t r i b u t i o n s o f moss t o t h e s o i l o r g a n i c m a t t e r and t h a t moss g r o w t h r e f l e c t e d t h e amount o f l i t t e r added i n t h e p a s t . Poor c o r r e l a t i o n s between t h e 0-5 cm C and N l e v e l s and t h e v a s c u l a r p l a n t c o v e r was p r o b a b l y because many o f t h e v a s c u l a r p l a n t s were a n n u a l s p e c i e s t h a t had n o t y e t c o n t r i b u t e d l i t t e r . C o r r e l a t i o n s between t h e d i f f e r e n t c o v e r t y p e s and t h e 5-10 cm C and N l e v e l s were g e n e r a l l y weaker t h a n t h o s e f o r t h e 0-5 cm C and N d a t a . The e x c e p t i o n t o t h i s was f o r t h e v a s c u l a r p l a n t c o v e r . C o r r e l a t i o n c o e f f i c i e n t s between t h e 5-10 cm %N and N/m3 and t h e v a s c u l a r p l a n t c o v e r were 0.63 and 0.64 r e s p e c t i v e l y , and were t h e s t r o n g e s t c o r r e l a t i o n s w i t h 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 i s d e p t h . 80 Table 1.15 Correlation coefficients among soil chemical and other properties of the untreated wasterock dumps. Bulk % <2mm Moss Vas.Pl. S.O.C. Moss+ Utter Density <2mm /rr.3 Vas.Pl. Depth (percent cover) pH ALL 0.38 -0.49 -0.29 0-5 0.41 -0.65 -0.53 -0.46 -0.47 -0.43 -0.58 -0.46 5-10 0.37 -0.59 -0.40 -0.48 -0.46 -0.42 -0.59 -0.45 %C ALL -0.29 0.18 -0.07 0-5 -0.61 0.45 0.08 0.86 0.23 0.81 0.75 0.69 5-10 0.09 -0.15 -0.18 0.25 0.42 0.22 0.39 0.05 C/m3 ALL -0.41 0.60 0.39 0-5 -0.62 0.75 0.45 0.82 0.24 0.78 0.73 0.70 5-10 -0.13 0.45 0.45 0.47 0.55 0.43 0.60 0.37 %N ALL -0.37 0.36 0.15 0-5 -0.51 0.53 0.29 0.82 0.31 0.85 0.77 0.63 5-10 -0.15 0.10 0.00 0.31 0.63 0.27 0.54 0.01 N/m3 ALL -0.39 0.61 0.46 0-5 -0.47 0.76 0.60 0.70 0.27 0.73 0.65 0.57 5-10 -0.26 0.47 0.39 0.44 0.64 0.41 0.63 0.21 avail. P ALL -0.32 0.42 0.28 0-5 -0.31 0.55 0.52 0.33 0.54 0.32 0.52 0.17 5-10 -0.35 0.43 0.24 0.54 0.41 0.43 0.61 0.48 avail.P ALL -0.26 0.55 0.47 /m3 0-5 -0.28 0.64 0.64 0.28 0.41 0.28 0.42 0.15 5-10 -0.27 0.53 0.42 0.42 0.43 0.37 0.53 0.35. C / N ALL 0.13 -0.07 -0.02 0-5 -0.04 -0.12 -0.20 -0.07 -0.13 -0.10 -0.12 -0.03 5-10 0.12 -0.04 0.04 -0.19 -0.23 -0.17 -0.25 -0.17 N/avail.P ALL 0.00 -0.13 -0.14 0-5 0.00 -0.11 -0.12 -0.08 -0.07 -0.06 -0.10 -0.14 5-10 0.09 -0.34 -0.33 -0.12 -0.21 -0.11 -0.19 -0.24 5-10 cm pH %C C/m3 %N N/m3 avail.P avail.P C / N N / 0-5 cm /m3 avail. P Bulk Density 0.50 -0.21 -0.30 -0.16 -0.27 -0.53 -0.43 0.05 0.04 %<2mm -0.66 -0.10 0.33 0.19 0.43 0.72 0.69 -0.09 -0.26 <2mm/m3 -0.47 -0.18 0.24 0.13 0.35 0.50 0.56 -0.06 -0.26 0-5 cm pH %C C/m3 %N N/m3 avail. P avail.P C / N N / 5-10 cm /m3 avail. P Bulk Density 0.39 0.20 -0.04 -0.03 -0.45 -0.17 -0.13 0.16 -0.09 %<2mm -0.61 0.10 0.39 0.30 0.45 0.40 0.38 -0.08 -0.13 <2mm/m3 -0.44 0.16 0.42 0.29 0.43 0.36 0.36 -0.02 -0.17 Al l : 0-5, 5-10, and 0-10 cm samples S.O.C. : moss + peat + litter 0-5 : 0-5 cm samples from sites abandoned in 1972 Vas.Pl. : Vascular Plants 5-10 : 5-10 cm samples from sites abandoned in 1972 81 P r i o r t o a t m o s p h e r i c i n p u t s , t h e o n l y N i n t h e w a s t e r o c k c o n s i s t e d o f t r a c e s o f ammonium n i t r a t e l e f t a f t e r b l a s t i n g . Most N a d d i t i o n s o c c u r r e d a t t h e s u r f a c e ( e . g . , p r e c i p i t a t i o n , moss and a l g a e growth, and l i t t e r a c c u m u l a t i o n ) . As a r e s u l t , f o r a l l t h e s i t e s , e x c e p t SEL.HN, t h e 0-5 cm N l e v e l s were s i g n i f i c a n t l y g r e a t e r t h a n t h e l e v e l s a t 5-10 cm ( T a b l e 1.16). As e x p e c t e d , t h e two u n v e g e t a t e d s i t e s (SEL.PO.U and SEL.HN) c o n t a i n e d t h e l e a s t N. N i t r o g e n l e v e l s were s i g n i f i c a n t l y h i g h e r on t h r e e o f t h e f o u r v e g e t a t e d a r e a s (LG.U.B, SEL.PO.V, and LG.V). On t h e two s i t e s where t h e p l a n t g r o w t h was weak (LG.U.B, and SEL.PO.V), t h e i n c r e a s e i n N was l i m i t e d t o t h e 0-5 cm l a y e r . T h i s was n o t t h e c a s e f o r LG.V, f o r w h i c h t h e av e r a g e 5-10 cm N/m3 c o n t e n t was s i g n i f i c a n t l y h i g h e r t h a n t h e average N/m3 c o n t e n t o f a l l o t h e r a r e a x d e p t h c o m b i n a t i o n s e x c e p t SEL.PO.V a t 0-5 cm. A l t h o u g h N was a l m o s t e n t i r e l y o r g a n i c , c a r b o n o c c u r r e d i n two f r a c t i o n s : o r g a n i c - C and m i n e r a l o r c a r b o n a t e - C . I n t h e two r e c e n t l y - b u i l t dumps (AR.82 and WR.82), where t h e r e was no o p p o r t u n i t y f o r o r g a n i c i n p u t s , one c a n assume t h a t a l l t h e C was i n m i n e r a l form. Assuming t h a t a l l t h e C was c a l c i t e , t h e c a l c i t e c o n t e n t o f t h e < 2 mm f r a c t i o n o f t h e unweathered p o t a s s i c (WR.82) and i n c o m p e t e n t (AR.82) w a s t e r o c k were 11% and 14% r e s p e c t i v e l y . These l e v e l s were much h i g h e r t h a n t h o s e r e p o r t e d i n t h e g e o l o g i c a l s u r v e y o f t h e s i t e ( S t e i n i n g e r 1985), i n w h i c h c a l c i t e was s a i d t o be a t r a c e m i n e r a l . One p o s s i b l e e x p l a n a t i o n f o r t h e h i g h < 2 Table 1.16 The probability that differences exist between the chemical properties of the 0-5 and 5-10 cm depths of the untreated wasterock dumps. Treatment Analysis 75.1 70.R 70F 70P 70PF 70AI pH .00* .00* .00* .00* .00* .14 % C .00* .41 .00* .00* .00* .06 C/m3 .00* .07 .00* .00* .00* .06 %N .00* .04* .00* .00* .00* .06 N/m3 .00* .19 .00* .00* .00* .06 avail.P .00* .00* .06 .00* .01* .06 avail.P/m3 .00* .00* .29 .02* .03* .06 C / N .00* .00* .08 .21 :38 .29 N/avail.P .or .30 .21 .00* .03* .14 * : significant at 0.05 level of probability 83 mm c a l c i t e l e v e l s found i n t h i s s t u d y was t h a t a l l t h e c a l c i t e p r e s e n t i n t h e o r i g i n a l r o c k ended up i n t h e < 2 mm f r a c t i o n o f t h e w a s t e r o c k . I f t h i s was t h e c a s e , t h e c a l c i t e c o n t e n t o f t h e o r i g i n a l r o c k would have been o n l y 2.6% i n WR.82 and 4.4% i n AR.82. Dumps exposed s i n c e 1972 c o n t a i n e d b o t h m i n e r a l and o r g a n i c forms o f C. The c a l c i t e and o r g a n i c m a t t e r c o n t e n t o f a number o f s i t e s a r e l i s t e d i n T a b l e 1.17. C a l c i t e was o n l y a s i g n i f i c a n t p r o p o r t i o n o f t h e t o t a l C i n samples whose pH was above 6.8. The d e c l i n e i n c a l c i t e as t h e pH i n c r e a s e d s u g g e s t t h a t t h e two p r o p e r t i e s were r e l a t e d . F o r a l l t h e samples i n T a b l e 1.17, 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 between c a l c i t e and pH was -0.67 . E x c l u d i n g t h e unweathered and t h e h o r n f e l s s i t e s i n c r e a s e d t h e r v a l u e t o -0.75 . The t r a c e s o f c a l c i t e i n low pH samples were p r o b a b l y s m a l l c r y s t a l s o c c l u d e d , and t h u s p r o t e c t e d , w i t h i n l a r g e s and g r a i n s . The o t h e r t r e n d shown i n T a b l e 1.17 i s t h e d e c r e a s e i n pH as o r g a n i c m a t t e r c o n t e n t i n c r e a s e d . The c o r r e l a t i o n between pH and t h e o r g a n i c m a t t e r had a c o e f f i c i e n t o f -0.80 A l t h o u g h none o f them were v e r y s t r o n g , t h e n e g a t i v e c o r r e l a t i o n s between pH and t h e v a r i o u s o r g a n i c c o v e r t y p e s a l s o s u g g e s t t h a t p l a n t growth and l i t t e r were a m a j o r s o u r c e o f a c i d i t y . The s t r o n g c o r r e l a t i o n s between N/m3 and pH c o n f i r m t h i s ( F i g u r e s 1.2 and 1.3). 84 Table 1.17 The pH and the calcite and organic matter contents of selected wasterock samples. Site Depth pH %calcite %orgai -C -C Untreated -WR.82 0-1 Ocm 7.69 1.17 0.00 WR.82 0-10cm 7.61 1.04 0.00 WR.82 0-1 Ocm 7.65 1.17 0.00 WR.82 0-10cm 7.55 1.03 0.00 AR.82 0-1 Ocm 7.71 1.25 0.00 AR.82 0-1 Ocm 7.65 0.89 0.00 AR.82 0-1 Ocm 7.38 0.93 0.00 AR.82 0-1 Ocm 7.64 2.41 0.00 SEL.PO.U 0-5cm 7.60 0.62 0.12 LG.U.S 0-5cm 7.50 0.24 0.02 SEL.HN 0-5cm 7.31 0.70 0.20 SEL.PO.U 0-5cm 7.30 0.32 0.00 SEL.HN 0-5cm 7.24 0.64 0.12 SEL.HN 0-5cm 7.15 0.26 0.43 LG.U.B 0-5cm 6.90 0.04 0.45 SEL.PO.V 0-5cm 6.80 0.17 0.33 SEL.PO.V 0-5cm 5.30 0.02 0.27 LG.V 0-5cm 4.10 0.00 1.04 LG.V 0-5cm 3.70 0.00 2.78 Treated 70P5 5- 10cm 5.30 0.07 0.66 70P5 5- 10cm 4.80 0.02 1.13 70P5 5-10cm 4.00 0.00 0.93 70P5 5-T0cm 3.90 0.05 8.71 8 5 N/m3 0.30-0.20-0.10- * . • ' .• • • 0,00 H 1 r 1 r-3.5 4.5 5.5 6.5 7.5 pH (CaCI2) Figure 1.2 pH vs N/m3 for the 0-5 cm depth on the untreated dumps (r- -0.79). N/m3 0.16 0.12-0.08-0.04 -0.00 -I 1 1 —r 4 5 6 7 8 pH (CaCI2) Figure 1.3 pH vs N/m3 for the 5-10 cm depth on the untreated dumps (r- -0.83). 8 6 A c c o r d i n g t o t h e i r a verage pH, t h e a r e a x d e p t h c o m b i n a t i o n s from t h e u n t r e a t e d dumps can be s e p a r a t e d as f o l l o w s : pH 7.7-7.5 7.3-7.0 6.5-6.2 4.2-4.0 a r e a x -WR.82 -SEL.HN -LG.U.B -LG.V d e p t h (0-10 cm) (0-10 cm) (0-5 cm) (0-10 cm) -AR.82 -LG.U.B -SEL.PO.V (0-10 cm) (5-10 cm) (0-5 cm) -SEL.PO.U -SEL.PO.V -TOP.SU (0-10 cm) (5-10 cm) (0-10 cm) W i t h t h e e x c e p t i o n o f a few groups i n t h e pH r a n g e s 7.3-7.0 and 6.5-6.2, a r e a x d e p t h c o m b i n a t i o n s i n d i f f e r e n t r a n g e s v a r i e d s i g n i f i c a n t l y . As e x p e c t e d , t h e unweathered, r e c e n t l y dumped m a t e r i a l s (AR.82 and WR.82) were i n t h e h i g h e s t pH range . I m m e d i a t e l y a f t e r t h e b e d r o c k i s b l a s t e d a p a r t , t h e pH o f t h e w a s t e r o c k s o i l w i l l be s i m i l a r t o t h e a b r a s i o n pH o f t h e r o c k . D e s p i t e a t l e a s t 8 y e a r s e x p o s u r e and l e a c h i n g , t h e aver a g e pH v a l u e s a t b o t h d e p t h s on t h e u n v e g e t a t e d p o t a s s i c SEL s i t e s (SEL.PO.U) were a l s o between 7.5 and 7.7. The most l i k e l y c a u se o f t h e s t a b l e pH a t SEL.PO.U was c a l c i t e d i s s o l u t i o n . SEL.PO.U had a s i g n i f i c a n t l y l o w e r %C and l e s s t h a n h a l f t h e C/m3 o f t h e r e c e n t l y exposed p o t a s s i c m a t e r i a l (WR.82). L i k e SEL.PO.U, b o t h d e p t h s o f t h e u n v e g e t a t e d h o r n f e l s SEL s i t e (SEL.HN) had pH v a l u e s h i g h e r t h a n 7. The h i g h %C and C:N r a t i o s u g g e s t e d t h a t t h e w a s t e r o c k s t i l l c o n t a i n e d h i g h l e v e l s o f c a l c i t e . The two o t h e r a r e a x d e p t h c o m b i n a t i o n s whose ave r a g e pH f e l l i n t h e range o f 7.3 t o 7.0 were t h e 5-10 cm samples 87 from SEL.PO.V and LG.U.B. A t b o t h s i t e s t h e p l a n t growth was weak and 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 h e m i c a l p r o p e r t i e s from t h e unweathered samples were r e s t r i c t e d t o t h e 0-5 cm l a y e r . Assuming a C:N r a t i o f o r o r g a n i c m a t t e r o f between 20 and 30, most o f t h e C i n t h e 0-5 cm l a y e r o f SEL.PO.V and LG.U.B was o r g a n i c , w h i l e a t 5-10 cm, t h e h i g h pH and h i g h C:N r a t i o i n d i c a t e d t h a t a s i g n i f i c a n t p r o p o r t i o n o f t h e C was c a l c i t e . The s u r f a c e s o f t h e s e s i t e s were n e a r t h e t h r e s h o l d p o i n t where c a l c i t e r e s e r v e s were e x h a u s t e d and., s m a l l o r g a n i c a c i d a d d i t i o n s and l e a c h i n g d r a m a t i c a l l y d e c r e a s e t h e pH. B o t h d e p t h s o f LG.V had a v e r a g e H i o n a c t i v i t i e s 100 t i m e s l a r g e r t h a n t h o s e o f any o t h e r u n t r e a t e d a r e a x d e p t h c o m b i n a t i o n . The low pH i n d i c a t e s t h a t n e i t h e r d e p t h c o n t a i n e d c a l c i t e , and t h u s a l l t h e C p r e s e n t i n t h e t o p 10 cm o f LG.V was o r g a n i c . O r g a n i c i n p u t s s h o u l d be e x p e c t e d as LG.V had t h e h i g h e s t p l a n t c o v e r ( 6 0 % ) . I n t h i s c o o l , humid e n v i r o n m e n t , t h e m i c r o b i a l d e c o m p o s i t i o n o f p l a n t r e s i d u e s r e s u l t s i n t h e f o r m a t i o n o f o r g a n i c a c i d s , w h i c h a r e r e s p o n s i b l e f o r low pH v a l u e s i n n a t u r a l s o i l s . The o t h e r p o s s i b l e c a use f o r low pH v a l u e s a t LG.V was s u l p h i d e o x i d a t i o n . I f , as s u g g e s t e d , LG.V s i t e s c o n t a i n e d i n c o m p e t e n t w a s t e r o c k , r o c k o f t h i s t y p e i s h i g h l y f r a c t u r e d and t h u s p e r m i t s q u i c k a c c e s s o f w a t e r , oxygen, and m i c r o o r g a n i s m s t o any s u l p h i d e g r a i n s t h a t a r e p r e s e n t . However, t h e s u l p h i d e c o n t e n t ( l a r g e l y p y r i t e ) o f t h e 88 K i t s a u l t w a s t e r o c k i s r e l a t i v e l y s m a l l ( S t e i n i n g e r 1985) and a c i d i f i c a t i o n by t h i s p r o c e s s w i l l be l i m i t e d . A c c o r d i n g t o 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 p r o p e r t y most s t r o n g l y r e l a t e d t o pH was a v a i l a b l e P ( F i g u r e s 1.4 and 5 ) . N o t a b l y , b o t h pH and a v a i l a b l e P a r e measures o f a v a i l a b l e r a t h e r t h a n t o t a l element c o n t e n t , and s i t e s whose pH was most v a r i a b l e a l s o had h i g h l y v a r i a b l e a v a i l a b l e P l e v e l s ( e . g . , LG.U.S). The i n c r e a s e i n a v a i l a b l e P as t h e r pH d e c r e a s e d can be e x p l a i n e d by t h e e f f e c t o f pH on a p a t i t e s t a b i l i t y . A p a t i t e was t h e o n l y common p r i m a r y P m i n e r a l f o u n d i n t h e w a s t e r o c k ( S t e i n i n g e r , 1985) and a p a t i t e s o l u b i l i t y i n c r e a s e s e x p o n e n t i a l l y as t h e pH d r o p s ( L i n d s a y & Moreno, 1960). I n t h e SEL samples, l e v e l s o f a v a i l a b l e P were h i g h e r a t 0-5 t h a n a t 5-10 cm. On t h e LG dump, a v a i l a b l e P l e v e l s a t 5-10 cm were g r e a t e r t h a n a t 0-5 cm. The LG dump d a t a was t h e o p p o s i t e o f what might be e x p e c t e d from t h e pH v a l u e s , and s u g g e s t t h a t e i t h e r P r e l e a s e d a t 0-5 cm was b e i n g f i x e d i n t o u n e x t r a c t a b l e forms, o r P r e l e a s e d a t t h e s u r f a c e was l o s t t h r o u g h l e a c h i n g . The o t h e r n o t a b l e f e a t u r e about t h e a v a i l a b l e P l e v e l s on t h e LG dump was t h e r e l a t i v e l y h i g h amounts o f a v a i l a b l e P a t LG.U.S. One e x p l a n a t i o n i s t h a t t h e pH d a t a o n l y p r o v i d e s a measure o f t h e p r e s e n t w e a t h e r i n g i n t e n s i t y . The d u r a t i o n o f l o w e r pH c o n d i t i o n s i s a l s o i m p o r t a n t , and t h e low 5-10 cm pH s u g g e s t s t h a t a d e c l i n e i n pH o c c u r r e d e a r l i e r on LG.U.S t h a n on LG.U.B o r SEL.PO.V. 89 available P (ppm) 25 3.6 4.6 6.6 6.5 7.5 pH (CaCI2) Figure 1.4 pH V8 available P for the 0-5 cm depth on the untreated dumps (r-0.79). available P (ppm) 30-20 10 4 6 6 7 8 pH (CaCI2) Figure 1.5 pH vs available P for the 5-10 cm depth on the untreated dumps (r-0.90). 90 4.1.2 F i e l d T r i a l s 4.1.2.1 S u r f a c e Cover T r e a t m e n t s a p p l i e d t o t h e f i e l d t r i a l s a r e d e s c r i b e d i n A p p e n d i x A, and a c o m p l e t e r e p o r t o f t h e r e s u l t i n g p l a n t g r o w t h i s p r e s e n t e d i n S e c t i o n 4.2. S o i l samples were t a k e n from t h e t r i a l s i n 1980. A c c o r d i n g t o t h e i r v a s c u l a r p l a n t c o v e r , t h e r a n k i n g o f t h e d i f f e r e n t t r e a t m e n t s i n 1980 was 70AI ( f e r t i l i z e d ) < 70R ( c o n t r o l ) < 75.1 ( f e r t i l i z e d slope). < 70PF (peat) < 70F ( f e r t i l i z e r ) < 70P ( p e a t ) ( T a b l e 1.18). W i t h t h e e x c e p t i o n o f 70AI, v a s c u l a r p l a n t g r o w t h on t h e s i t e s sampled was a l m o s t e n t i r e l y p e r e n n i a l a g r o n o m i c s . T r e atment 70AI was s p r i n g r y e ( S e c a l e c e r e a l e L.) and b a r l e y (Hordeum v u l q a r e L.) sown on f e r t i l i z e d w a s t e r o c k . I n 1980, i t was t h e t r e a t m e n t i n T r i a l 70.1 w i t h t h e most v i g o r o u s i n v a s i o n o f n a t i v e s p e c i e s ( e . g . , w i l l o w and c o t t o n w o o d ) . The r e l a t i v e r a n k i n g o f d i f f e r e n t t r e a t m e n t s a c c o r d i n g t o moss c o v e r was s i m i l a r t o t h a t f o r v a s c u l a r p l a n t s ( T a b l e 1.18). L i k e on t h e u n t r e a t e d dumps, t h e moss c o v e r on t h e f i e l d t r i a l s was g e n e r a l l y g r e a t e r t h a n t h a t o f t h e v a s c u l a r p l a n t s . One r e s u l t o f s t r o n g e r p l a n t g r o w t h on t h e f i e l d t r i a l s t h a n on t h e u n t r e a t e d dumps was t h e f o r m a t i o n o f t h i c k e r s u r f a c e l i t t e r l a y e r s . F i e l d t r i a l s , l i k e t h e u n t r e a t e d s i t e s , showed no n o t i c e a b l e i n c o r p o r a t i o n o f s u r f a c e l i t t e r . The t h i c k n e s s o f t h e s u r f a c e o r g a n i c l a y e r s r e f l e c t e d b o t h p r e v i o u s p l a n t growth and p e a t a p p l i c a t i o n . The s h a r p 91 Table 1.18 The surface cover on sampled areas of the field trials. Moss Litter Lichen Wort Inv. Grass Legume Litter Treatment 80 81 83 83 83 83 83 80 81 83 80 81 83 Depth (Percent Cover) (cm) 70R1 6 6 12 5 1 tr tr 3 2 tr tr 0 0 0.2 70R5 19 6 22 1 1 0 1 5 tr 1 4 3 2 0.3 70R6 30 15 27 4 1 tr 1 6 1 1 1 1 1 0.3 70F1 69 63 58 16 tr tr tr 36 14 2 5 4 2 1.4 70F5 78 72 80 3 0 1 0 29 17 11 34 36 39 2.3 70F6 72 63 62 5 p 0 tr 21 9 4 11 12 8 2.1 70P1 91 72 84 9 0 tr 1 55 34 11 12 11 6 4.3 70P5 95 89 95 tr 0 0 1 37 26 12 38 47 48 5.3 70P6 92 91 92 3 0 tr tr 21 7 6 15 13 12 3.8 70PF1 80 70 64 19 0 tr 1 39 17 8 5 2 1 2.9 70PF5 63 32 41 16 tr 0 1 13 5 2 9 7 7 3.3 70PF6 65 37 45 18 tr 0 1 14 4 2 7 2 3 2.5 70 Al* 18 nm nm 38 0 0 46 3 nm nm 3 nm nm 1.7 75.1 • 31 nm nm 1 0 0 0 4 nm nm 4 nm nm 0.8 nm : not measured Inv : naturally invading vascular plants * : all data measured in 1980 Litter : litter + peat Wort : liverwort tr : trace 92 boundary between t h e s u r f a c e o r g a n i c m a t t e r and t h e w a s t e r o c k i n d i c a t e d t h a t l i t t l e o r no f a u n a l m i x i n g had o c c u r r e d . O r g a n i c m a t t e r added t o t h e s u r f a c e remained t h e r e i n a L F H - l i k e l a y e r . J u d g i n g from t h e t h i c k n e s s o f t h e s u r f a c e o r g a n i c l a y e r s , o r g a n i c m a t t e r a d d i t i o n s from p l a n t g r o w t h on 70F had been a t l e a s t as l a r g e as t h e amount o f o r g a n i c m a t t e r a p p l i e d by t h e p e a t t r e a t m e n t p l u s p o o r p l a n t g r o w t h on 70PF. Treatment 7OP had b o t h s t r o n g p l a n t g r o w t h and a p e a t amendment, and as a r e s u l t , t h e a v e r a g e . , t h i c k n e s s o f i t s o r g a n i c l a y e r (4.5 cm) was o n l y s l i g h t l y l e s s t h a n t h e combined t o t a l f o r 70PF and 70F (4.8 cm). 4.1.2.2 P h y s i c a l P r o p e r t i e s S o i l p h y s i c a l d a t a f o r i n d i v i d u a l samples a r e t a b u l a t e d i n A p p e n d i x B. L i k e o t h e r s o i l p r o p e r t i e s , t h e p h y s i c a l p r o p e r t i e s showed no s t a t i s t i c a l l y s i g n i f i c a n t r e s p o n s e t o t h e t y p e o f se e d mix sown. There were however many s i g n i f i c a n t d i f f e r e n c e s as a r e s u l t o f s u r f a c e t r e a t m e n t s ( T a b l e 1.19). The f i e l d t r i a l s , l i k e t h e u n t r e a t e d dumps, p r o d u c e d a weak n e g a t i v e c o r r e l a t i o n between b u l k d e n s i t y and % < 2 mm, and a s t r o n g e r p o s i t i v e c o r r e l a t i o n between % < 2 mm and w e i g h t < 2 mm/m3 ( T a b l e 1.20). Compared t o f i n d i n g s from t h e u n t r e a t e d dumps, t h e range i n average v a l u e s was s m a l l e r f o r % < 2 mm and wt. o f < 2 mm/m3 and l a r g e r f o r b u l k d e n s i t y . The narrow range i n < 2 mm c o n t e n t was p r o b a b l y because a l l Table 1.19 Soil physical properties of the field trials. %<2mm <2mm/m3 Bulk Density Treatment Depth (kg/m3) Ikg/m3) 70AI 0 5cm 7 (3) a 157 (71) ab 2169 (98) a 70P 5-10cm 12 (4) a 252 (82) be 2059 (532) ab 70PF 5- 10cm 14 (7) a 261 (85) bed 2096 (594) ab 70PF 0-5cm 14 (8) a 232 (139) abc 1693 (409) c 70AI 5-10cm 14 (2) ab 276 (53) abede 1914 (105) b 70R 0-5 cm 15 (4) ab 294 (91) cde 2013 (342) ab 70F 0-5cm 16 (7) abc 212 (81) ab 1449 (358) d 70F 5-10cm 17 (6) abc 300 (103) cde 1860 (293) b 70R 5-10cm 18 (8) bed 353 (124) de 2113 (546) a 75.1 5- 10cm 21 (5) d 385 (96) e 1868 (212) b 75.1 0-5cm 21 (12) d 321 (168) cde 1551 (268) c 70P 0-5cm 22 (11) d 200 (90) a 1011 (354) e 77.84 0-1 Ocm 20 (4) cd 0 (0) : mean (standard deviation) means followed by the same letter were not significantly different at p = 0.5 94 t h e t r e a t m e n t s sampled were on t h e same dump, and t h u s c o m p r i s e d o f s i m i l a r m a t e r i a l . A l t h o u g h , l i k e T r i a l s 75.1 and 77.1, T r i a l 70.1 was c o m p r i s e d o f p o t a s s i c r o c k , s e v e r a l o f t h e t r e a t m e n t x d e p t h c o m b i n a t i o n s ( e . g . , 0-5 cm 70R, 70F and 70PF) from i t had % < 2 mm c o n t e n t s w h i c h were more l i k e t h e u n t r e a t e d h o r n f e l s w a s t e r o c k (SEL.HN). The low % < 2 mm on T r i a l 70.1 was p r o b a b l y caused by t h e manner i n w h i c h t h e t r i a l was b u i l t . U n l i k e o t h e r t r i a l s , t h e 70.1 s i t e was l e v e l l e d by a g r a d e r b e f o r e amendments were a p p l i e d . As i t l e v e l s t h e s u r f a c e , a g r a d e r shakes and moves t h e m a t e r i a l , i n a p r o c e s s s i m i l a r t o s i e v i n g . W i t h s t o n e y m a t e r i a l l i k e w a s t e r o c k t h a t l a c k s c o h e s i o n , g r a d i n g shakes l o o s e s m a l l e r p a r t i c l e s w h i c h f a l l i n t o s p a c e s t h a t open below. S t o n e s t h a t a r e t o o l a r g e t o f i t i n t o c r e v a s s e s a r e l e f t s t r a n d e d a t t h e s u r f a c e . G r a d i n g may a l s o compact t h e s u r f a c e . The r e s u l t was a v e r y low 0-5 cm % < 2mm, t h e most extreme example o f w h i c h was 70AI. A f t e r g r a d i n g , t h e p a r t i c l e s i z e d i s t r i b u t i o n o f most o f T r i a l 70.1 was p r o b a b l y l i k e t h e p r e s e n t c o n d i t i o n o f t h e u n f e r t i l i z e d w a s t e r o c k (70R) p l o t s . S u b s e q u e n t l y , o r g a n i c m a t t e r , added e i t h e r as a p e a t amendment o r t h r o u g h r o o t and herbaceous g r o w t h , m o d i f i e d t h e p h y s i c a l p r o p e r t i e s o f t h e s u r f a c e . As i t l a c k e d a p e a t amendment and had l i t t l e p l a n t g r o w t h , t h e e f f e c t o f t h e s e p r o c e s s e s on 70R were m i n i m a l . As was found on t h e u n t r e a t e d s i t e s , t h e s o i l p h y s i c a l p r o p e r t y most s t r o n g l y c o r r e l a t e d w i t h t h e o r g a n i c c o v e r t y p e s was b u l k d e n s i t y . B u l k d e n s i t y c o r r e l a t e d most s t r o n g l y w i t h c o v e r t y p e s i n c l u d i n g moss ( T a b l e 1.20). On a l l t h e t r e a t m e n t s , e x c e p t 70R, t h e 0-5 cm b u l k d e n s i t y was s i g n i f i c a n t l y l o w e r t h a n a t 5-10 cm ( T a b l e 1.21). The 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 w i t h d e p t h i n % < 2 mm a t 0-5 cm was on 70P, t h e t r e a t m e n t w i t h t h e l a r g e s t d i f f e r e n c e between i t s 0-5 cm and 5-10 cm o r g a n i c - C c o n t e n t s . P erhaps t h e g r e a t e s t e f f e c t o f o r g a n i c m a t t e r a d d i t i o n on p a r t i c l e s i z e was i n r a i s i n g t h e s u r f a c e . I n t h i s manner, s u r f i c i a l o r g a n i c a d d i t i o n s d i l u t e d t h e amount o f w a s t e r o c k i n t h e 0-5 cm l a y e r , d r o p p i n g a p o r t i o n o f t h e o r i g i n a l f i n e s - d e f i c i e n t s u r f a c e m a t e r i a l i n t o t h e 5-10 cm d e p t h . As a r e s u l t o f b o t h c o n t i n u o u s l y s t r o n g p l a n t g r o w t h and t h e o r i g i n a l p e a t amendment, t h e t h i c k n e s s o f t h e LFH-l i k e l a y e r was g r e a t e s t on t h e 70P p l o t s . On a v e r a g e , 4.4 cm o f t h e upper 0-5 cm o f 70P was p e a t and l i t t e r , p u t t i n g most o f t h e o r i g i n a l h i g h d e n s i t y upper 5 cm o f w a s t e r o c k s o i l i n t h e 5-10 cm l a y e r . A t 5-10 cm, 70P had one o f t h e h i g h e s t b u l k d e n s i t i e s and t h e s m a l l e s t < 2 mm c o n t e n t s . C o n v e r s e l y , i n t h e h i g h l y o r g a n i c s u r f a c e , 7OP had t h e l o w e s t b u l k d e n s i t y and t h e h i g h e s t % < 2 mm, and t h e 0-5 cm b u l k d e n s i t y was s i g n i f i c a n t l y l o w e r t h a n t h a t o f a l l t h e t r e a t m e n t s . As e x p e c t e d from t h e i r s h a l l o w e r s u r f a c e o r g a n i c l a y e r s , t h e 0-5 cm d e p t h s on t h e 7OF and 70PF t r e a t m e n t s c o n t a i n e d s i g n i f i c a n t l y l e s s % < 2 mm and had h i g h e r b u l k 96 Table 1.20 Correlation coefficients for soil physical properties of the field trials. Bulk Density %<2mm <2mm/m3 Depth ALL 0-5 5-10 ALL 0-5 5-10 0-5 5-10 Bulk Density X X X %<2mm -.44 -.43 -.51 X X X <2mm/m3 .19 .19 -.03 .74 .76 .84 X X % Moss -.64 . -.08 .32 -.12 -.07 -.15 % Vascular Plant -.39 -.18 .06 .01 -.13 -.06 % Grass -.28 -.21 .12 -.09 -.03 -.18 % Legume -.26 -.05 .00 .06 -.12 .05 % Moss + Peat + Litter -.58 -.01 .31 -.16 -.02 -.18 % Moss + Vascular Plant -.64 -.14 .26 -.08 -.11 -.14 Utter (cm) -.36 .33 .22 -.44 -.04 -.33 Table 1.21 The probability that differences exist between the soil physical properties of the 0-5 and 5-10 cm depths of the field trials. Treatment %<2mm <2mm/m3 Bulk Density 75.1 0.08 0.36 0.00 • 70R 0.16 0.19 0.19 70F 0.24 0.00 • 0.00 • 70P 0.00 0.04 * 0.00 • 70PF 0.27 0.17 0.01 • ' significant at the 0.05 level of probability 9 7 d e n s i t i e s t h a n t h e 7OP p l o t s . Comparing t h e two, 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 i n t h e i r p h y s i c a l p r o p e r t i e s was t h a t 7OF had a l o w e r 0-5 cm b u l k d e n s i t y . Thus 10 y e a r s o f s t r o n g p l a n t growth a f t e r t h e f e r t i l i z e r t r e a t m e n t (70F) had c r e a t e d s l i g h t l y b e t t e r p h y s i c a l c h a r a c t e r i s t i c s t h a n t h e i n i t i a l p e a t amendment w i t h p o o r p l a n t growth (7 0 P F ) . The f i n e s - c o n t a i n i n g p o r t i o n a t t h e t o p o f s l o p e T r i a l 75.1 had a r e l a t i v e l y h i g h < 2 mm c o n t e n t and low b u l k d e n s i t y , p r e s u m a b l y because i t was n o t compacted by t r u c k s . o r r e w o r ked by t h e g r a d e r . A l t h o u g h a l a c k o f f i n e s and a h i g h b u l k d e n s i t y a r e n o t d e s i r a b l e c h a r a c t e r i s t i c s , t h e most v i g o r o u s n a t u r a l p l a n t i n v a s i o n o c c u r r e d on 70AI, t h e s i t e w i t h t h e l o w e s t % < 2 mm and h i g h e s t b u l k d e n s i t y . T h i s s u g g e s t s t h a t i f t h e dump benches a r e f e r t i l i z e d and sown w i t h a g r o n o m i c s , c o m p e t i t i o n f o r space i s a g r e a t e r l i m i t a t i o n t o p l a n t i n v a s i o n t h a n t h e p h y s i c a l c o n d i t i o n s . A h i g h c o a r s e fragment c o n t e n t r e s i s t s c o m p a c t i o n by t r u c k s , r e s u l t s i n good d r a i n a g e , and t h u s i s somewhat d e s i r a b l e . However, t h e f i n e r f r a c t i o n i s a l s o n e c e s s a r y and t h e l a c k o f f i n e s on a l l b u t t h e u p p e r p a r t o f t h e s l o p e s was an o b v i o u s impediment t o g r o w t h . The h i g h b u l k d e n s i t y on T r i a l 70.1 c o u l d have been p r e v e n t e d by r i p p i n g t h e s u r f a c e , r a t h e r t h a n g r a d i n g i t f l a t . H a v i n g a r o u g h e r s u r f a c e would a l s o c r e a t e a more v a r i e d m i c r o c l i m a t e , i n c r e a s i n g t h e r e t e n t i o n o f a i r b o r n e 98 seed and hence n a t u r a l p l a n t i n v a s i o n ( L a v k u l i c h e t a l . , 1976). The s u r f a c e o f t h e t r i a l s , l i k e t h e u n t r e a t e d dumps, c o n t a i n e d v e r y l i t t l e c l a y and a t l e a s t 50% o f t h e < 2 mm f r a c t i o n was s a n d - s i z e d ( T a b l e 1.21). Based on ave r a g e sand, s i l t , and c l a y c o n t e n t s , t h e < 2 mm f r a c t i o n s o f a l l t h e t r e a t m e n t s were c l a s s i f i e d as sandy loams. A few i n d i v i d u a l samples i n d i f f e r e n t groups were loamy sands and s e v e r a l 0-5 cm samples from 7OP were loams. Compared t o t h e o t h e r g r o u p s , t h e 0-5 cm l a y e r o f 70P c o n t a i n e d l e s s sand and more s i l t and c l a y . One e x p l a n a t i o n f o r t h i s was t h a t t h e low pH and h i g h o r g a n i c c o n t e n t c a used more i n t e n s e p a r t i c l e breakdown t h a n i n any o t h e r t r e a t m e n t x d e p t h c o m b i n a t i o n . A n o t h e r p o s s i b l e r e a s o n was t h a t t h e low p r o p o r t i o n o f sand i n 70P was an a r t i f a c t o f t h e p r e -t r e a t m e n t u s e d p r i o r t o t h e t e x t u r a l a n a l y s i s . A d d i n g more b l e a c h i n o r d e r t o o x i d i s e t h e h i g h e r o r g a n i c m a t t e r c o n t e n t o f t h e s e samples m i g h t have c a u s e d more p a r t i c l e d e g r a d a t i o n . A l t e r n a t i v e l y , t h e s i l t and c l a y f r a c t i o n s o f 7OP c o u l d c o n t a i n u n o x i d i z e d o r g a n i c m a t t e r . O t h e r t h a n 70P, t h e samples from t h e f i e l d t r i a l s a l l had t h e same t e x t u r e as t h e u n t r e a t e d dump samples. 99 Table 1.22 Soil texture information for different treatments in the field trials. 0-5cm 5-1 Ocm Treatment Sand Silt Clay Texture Sand Silt Clay Texture Averages 75.1 69 21 10 S.I. 66 22 11 s.l. 70R 70 22 7 s.l. 62 26 12 s.l. 70F 72 20 8 S.I. 68 24 8 s.l. 70P 53 35 12 S. l . 66 26 8 s.l. 70PF 62 27 11 s.l. 65 26 9 s.l. 70AI 69 22 10 s.l. 72 21 8 s.l. Standard Deviation 75.1 9.5 7.0 5.3 4.0 8.6 4.9 70R 8.1 8.7 3.5 8.0 5.2 4.7 70F 5.0 4.5 4.2 6.6 4.7 3.8 70P 8.3 9.7 2.0 6.3 5.2 3.3 70PF 4.3 2.1 3.2 2.9 3.5 2.9 70AI 0.7 2.1 2.8 3.5 7.8 4.2 s.l. : sandy loam 100 4.1.2.3 C h e m i c a l P r o p e r t i e s The s o i l c h e m i c a l p r o p e r t i e s o f i n d i v i d u a l samples can be f o u n d i n App e n d i x B. U n l i k e t h e u n t r e a t e d a r e a s , a l l t h e f i e l d t r i a l t r e a t m e n t s had had a t l e a s t some p l a n t growth on them. One r e s u l t o f t h e s t r o n g e r p l a n t growth was t h e a d d i t i o n o f more C and N. L i k e t h e u n t r e a t e d s i t e s , t h e 0-5 cm d e p t h s c o n t a i n e d more C/m3 and N/m3 t h a n t h e 5-10 cm l a y e r ( T a b l e . 1.23 and 1.24). The e x c e p t i o n was t h e u n f e r t i l i z e d w a s t e r o c k (70R), w h i c h as a r e s u l t o f p o o r p l a n t g r o w t h , no p e a t amendment, and t h e p r e s e n c e o f c a l c i t e , c o n t a i n e d more C a t 5-10 cm. The dr o p i n pH a t t h e s u r f a c e o f 70R can be a t t r i b u t e d t o a l o s s o f c a l c i t e . The o t h e r t r e a t e d a r e a w i t h low C and N l e v e l s 'was t h e u n f e r t i l i z e d s l o p e ( 7 5 . 1 ) . V i s u a l o b s e r v a t i o n s made p r i o r t o 1980 ( P r i c e , 1982) and measurements o f p l a n t g r o w t h made i n t h i s s t u d y i n d i c a t e t h a t t h e p r i m a r y cause o f t h e low C and N l e v e l s on 75.1 was p o o r p l a n t g r o w t h . A l t h o u g h 75.1 was f e r t i l i z e d , t h e p o o r g r o w t h c o u l d be due t o a l a c k o f N. Ave r a g e 0-5 cm and 5-10 cm N l e v e l s f o r 75.1 were l o w e r t h a n t h a t t h o s e o f 70R. W h i l e 70F and 70PF d i f f e r e d s i g n i f i c a n t l y i n pH and a v a i l a b l e P, t h e y c o n t a i n e d comparable amounts o f C and N. E l e v e n y e a r s o f r e l a t i v e l y s t r o n g p l a n t g r o w t h on f e r t i l i z e d w a s t e r o c k (70F) produce d o n l y s l i g h t l y l e s s C/m3 t h a n p o o r p l a n t g r o w t h p l u s t h e p e a t amendment on 70PF. Average N/m3 101 Table 1.23 Soil chemical properties of the field trials. Site Depth pH %C C/m3 (kg/m3) 70R 5-10cm 7.1 (0.5) a 0.7 (0.2) be 2.3 (0.8) bd 75.1 5-1 Ocm 6.5 (0.8j b 0.3 (0.2) a 1.1 (0.6) a 70F 5-10cm 5.9 (1.1) be 0.8 (0.4) c 2.3 (1.3) b 75.1 0-5cm 5.8 (0.9) cd 0.6 (0.3) b 1.9 (1.2) bed 70R 0-5cm 5.6 (1.1) cde 0.7 (0.4) b 1.9 (1.2) bd 70AI 5-1 Ocm 5.4 (1.0) bede 0.3 (0.1) a 0.8 (0.2) a 70PF 5-10cm 5.4 (1.1) d 0.9 (1.1) be 2.0 (1.7) ad 70P 5-1 Ocm 4.9 (1.1) ef 2.0 (2.4) d 5.4 (7.0) c 70AI 0-5cm 4.7 (0.3) ef 1.2 (0.7) bed 1.7 (0.7) abc 70F 0-5cm 4.3 (0.6) f 5.1 (3.3) e 10.0 (6.4) f 70PF 0-5cm 4.2 (0.7) g 6.2 (2.9) e 13.7 (1.2.3) f • 70P 0-5cm 4.1 (0.6) h 12.5 (3.1) f 24.6 (12.5) g Site Depth %N N /m3 avail.P (kg/m3) (ppm) 70R 5-10cm 0.020 (0.006) be 0.07 (0.01) cd 1 (1) a 75.1 5-1 Ocm 0.007 (0.002) a 0.03 (0.01) a 9 (9) bed 70F 5-1 Ocm 0.039 (0.018) e 0.12 (0.08) d 17 (16) deg 75.1 0-5cm 0.031 (0.018) de 0.11 (0.12) d 23 (18) efg 70R 0-5cm 0.031 (0.017) cde 0.08 (0.04) cd 3 (2) a 70AI 5-10cm 0.015 (0.006) b 0.04 (0.01) ab 5 (5) abce 70PF 5-10cm 0.030 (0.025) bed 0.07 (0.05) bed 7 (10) ab 70P 5-10cm 0.067 (0.058) e 0.17 (0.17) d 15 (10) efg 70AI 0-5cm 0.065 (0.048) bede 0.08 (0.03) be 26 (22) gh 70F 0-5cm 0.167 (0.08) f 0.33 (0.19) e 31 (17) i 70PF 0-5cm 0.211 (0.099) f 0.39 (0.17) e 14 (9) e 70P 0-5cm 0.369 (0.213) g 0.61 (0.24) f 29 (6) h Site Depth avail.P /m3 C / N xC/xN N /avail .P (g/m3) 70R 5-10cm 0.3 (0.3) a 34 (8) a 34 250 (151) a 75.1 5-10cm 3.4 (3.2) c 46 (25) a 45 14 (10) g 70F 5-1 Ocm 5.1 (5.1) cd 21 (8) cd 21 44 (32) de 75.1 0-5cm 6.5 (4.1) d 21 (9)c 20 20 (17) fg 70R 0-5cm 1.0 (0.8) b 21 (6) cd 22 177 (185) abc 70AI 5-1 Ocm 1.2 (1.0) ab 22 (4) b 20 67 (49) abd 70PF 5-10cm 1.8 (2.7) b 36 (25) abc 30 89 (79) be 70P 5-10cm 3.9 (3.3) c 31 (16) ab 29 56 (48) de 70AI 0-5cm 2.8 (1.2) cd 23 (5) b 19 28 (6) ef 70F 0-5cm 5.8 (3.0) d 30 (14) abd 30 82 (97) cd 70PF 0-5cm 2.6 (1.4) c 31 (11) ab 29 185 (147) ab 70P 0-5cm 5.8 (2.9) d 37 (17) ab 34 135 (84) b 7 (9) : average (standard deviation) means followed by the same letter were not significantly different at p = 0.5 102 Table 1.24 The probability that differences exist between the physical properties of the 0-5 and 5-10 cm depths on the treated dumps. 75.1 70R 70F 70P 70PF 70AI pH .00* .00* .00* .00* .00* .14 %C .00* .41 .00* .00* .00* .06 C/m3 .00* .07 .00* .00* .00* .06 %N .00* .04* .00* .00* .00* .06 N/m3 .00* .19 .00* .00* .00* .06 avail. P .00* .00* .06 .00* .01* .06 avail.P /m3 .00* .00*' .29 .02* .03* .06 C / N .00* .00* .08 .21 .38 . .29 N /avail.P .01 • .30 .21 .00* .03* .14 significant at 0.05 level of probability c 12-8 4 -O 0-5 cm r- -0.63 + 6-10 cm r» -0.35 + 4.5 5 + + o o + • J-5.5 6 pH (CaCI2) + ~i 6.5 Figure 1.6 pH vs %C for the field trial treatment x depth averages. 7 7.5 103 l e v e l s were s l i g h t l y h i g h e r on 7OF, presumably as a r e s u l t o f t h e s t r o n g legume growth on 70F5. As one would e x p e c t from t h e t h i c k e r s u r f a c e o r g a n i c l a y e r , a t b o t h 0-5 and 5-10 cm, 70P had h i g h e r C and N l e v e l s t h a n any o f t h e o t h e r t r e a t m e n t s . Amounts o f C and N i n 7OP were a p p r o x i m a t e l y e q u a l t o t h e sum o f t h e s e f o r 7OF and 70PF. I n t h e f i e l d t r i a l s , s o i l C and N were l a r g e l y p r e s e n t i n t h e o r g a n i c form. The s t r o n g e r c o r r e l a t i o n s between C and N a t 0-5 cm t h a n a t 5-10 cm ( T a b l e 1.25) were due t o a g r e a t e r s p r e a d i n v a l u e s a t 0-5 cm and t h e absence o f c a l c i t e . The s o u r c e o f o r g a n i c m a t t e r a f f e c t e d t h e C:N r a t i o . - A verage C:N r a t i o s were s i g n i f i c a n t l y h i g h e r on t h e peat-amended t r e a t m e n t s (7OP and 70PF) t h a n on t r e a t m e n t s on w h i c h t h e main s o u r c e o f o r g a n i c m a t t e r was p l a n t g r o w t h ( e . g . , 7 0 F ) . Through t h e f o r m a t i o n o f o r g a n i c a c i d s , o r g a n i c m a t t e r a d d i t i o n s c a n l o w e r t h e pH. The 0-5 cm l a y e r , t h e zone o f maximum o r g a n i c a d d i t i o n s , was t h e most a c i d i c f o r a l l t h e t r e a t m e n t s . A l l o f t h e t r e a t m e n t s w i t h s t r o n g p l a n t growth o r on w h i c h p e a t was a p p l i e d had C a C l 2 pH v a l u e s l o w e r t h a n 5. The r e l a t i o n s h i p between o r g a n i c m a t t e r and pH i s i l l u s t r a t e d by t h e p l o t o f average C v e r s u s pH ( F i g u r e 1.6), w h i c h shows a c u r v i l i n e a r r e l a t i o n s h i p . A t h i g h pH t h e r e a r e r e l a t i v e l y l a r g e d r o p s i n pH w i t h o n l y s m a l l i n c r e a s e s i n C. The l a r g e pH d r o p s s u g g e s t t h a t i n t h i s pH range t h e 104 Table 1.25 Correlation coefficients for soil chemical properties of the field trials. P H ALL 0-5 5-10 P H X X X %C C/m3 %N N/m3 avail.P avail.P /m3 C / N %C ALL 0-5 5-10 -0.53 -0.53 -0.35 X X X C/m3 ALL 0-5 5-10 -0.47 -0.47 -0.27 0.85 0.80 0.94 X X X %N ALL 0-5 5-10 -0.46 -0.40 -0.43 0.86 0.82 0.83 0.54 0.43 0.78 X X X N/m3 ALL 0-5 5-10 -0.48 -0.42 -0.34 0.83 0.79 0.77 0.80 0.76 0.85 0.82 0.77 0.91 X X X avail.P ALL -0.29 0.44 0.32 0.36 0.33 X (ppm) 0-5 -0.10 0.36 0.20 0.27 0.20 X 5-10 -0.26 0.28 0.30 0.29 0.31 X avail.P ALL. -0.15 0.22 0.32 0.08 0.27 0.81 X /m3 0-5 0.00 0.15 0.29 -0.05 0.19 0.72 X 5-10 -0.12 0.22 0.31 0.20 0.33 0.93 X C / N ALL 0-5 5-10 0.04 -0.26 0.15 0.24 0.58 0.10 0.34 0.73 0.11 -0.03 0.13 -0.22 0.06 0.37 -0.21 0.02 0.22 -0.08 0.05 X 0.24 X -0.04 X N / ALL 0.05 0.27 0.16 0.35 0.27 -0.29 avail.P 0-5 0.07 0.25 0.12 0.37 0.25 -0.38 5-10 0.24 0.09 0.04 0.15 0.10 -0.38 -0.40 -0.08 -0.49 0.05 -0.39 -0.17 ALL : 0-5, 5-10, and 0-10 cm samples 105 w a s t e r o c k s o i l had v e r y l i t t l e pH b u f f e r i n g c a p a b i l i t y , o t h e r p r o c e s s e s such as l e a c h i n g and o x i d a t i o n c o n t r i b u t e d t o t h e a c i d i t y , and t h a t t h e t o t a l C and N l e v e l s were n o t good measures o f t h e a c i d i f y i n g a c t i o n o f o r g a n i c m a t t e r . F o r example, t h e l e v e l s o f %C a t 5-10 cm do n o t n e c e s s a r i l y i n d i c a t e t h e r a t e a t w h i c h o r g a n i c a c i d s have l e a c h e d t h r o u g h t h i s l a y e r . Nor do t h e y i n d i c a t e t h e s t r e n g t h o f t h e a c i d s o r f o r how l o n g l e a c h i n g has been o c c u r r i n g . O r g a n i c a c i d a d d i t i o n s t o t h e 5-10 cm l a y e r o f t h e p e a t amended s i t e s w i l l have s t a r t e d e a r l i e r t h a n on t h e f e r t i l i z e d w a s t e r o c k ( 7 0 F ) . T h i s may e x p l a i n why a t 5-10 cm, 70PF had a s i g n i f i c a n t l y l o w e r pH b u t c o n t a i n e d l e s s C t h a n 70F. The i m p o r t a n c e o f t h e s u r f a c e c o n d i t i o n s i n c o n t r o l l i n g t h e 5-10 cm pH was i l l u s t r a t e d by t h e s t r o n g c o r r e l a t i o n between t h e 0-5 cm and t h e 5-10 cm pH v a l u e s ( r=0.74). Below about pH 4.8, t h e r a t e o f pH d e c r e a s e r e l a t i v e t o t h e i n c r e a s e i n C becomes s t e a d i l y s m a l l e r . T h i s s u g g e s t s some form o f pH b u f f e r i n g . B u f f e r i n g may r e s u l t from e l e m e n t s r e l e a s e d by w e a t h e r i n g , such as Fe and A l , o r b ecause t h e pH approached t h e i s o e l e c t r i c pH o f o r g a n i c a c i d f u n c t i o n a l g r o u p s . A d e c r e a s e i n pH w i l l a c c e l e r a t e m i n e r a l w e a t h e r i n g , r e l e a s i n g e l e m e n t s l i k e A l w h i c h p l a y an i m p o r t a n t r o l e i n r e g u l a t i n g s o i l pH. On t h e f i e l d t r i a l s , t h e r e were no s t r o n g c o r r e l a t i o n s w i t h a v a i l a b l e P, i n d i c a t i n g t h a t s e v e r a l f a c t o r s p l a y e d a r o l e i n P a v a i l a b i l i t y . F o r example, by i n c r e a s i n g t h e 106 r e l e a s e and a v a i l a b i l i t y o f Fe and A l , a c i d i c c o n d i t i o n s , w h i c h a c c e l e r a t e a p a t i t e w e a t h e r i n g , may a l s o have a c c e l e r a t e d P f i x a t i o n . The p r e s e n c e o f r e s i d u a l f e r t i l i z e r may e x p l a i n why l e v e l s o f a v a i l a b l e P/m3 i n 70P, 70F, and 75.1 were s i g n i f i c a n t l y h i g h e r t h a n t h o s e o f 70PF and 7OR. N o t a b l y , t h e d i f f e r e n c e s i n a v a i l a b l e P l e v e l s between 70P and 70PF were s i m i l a r t o d i f f e r e n c e s i n t h e i r C and N c o n t e n t s . T h i s o b s e r v a t i o n s u g g e s t s t h a t t h e r e was a c o r r e l a t i o n between^ t h e a v a i l a b l e P and t h e o r g a n i c m a t t e r c o n t e n t on t h e p e a t amended p l o t s , and t h a t t h e P r e l e a s e d by t h e B r a y e x t r a c t a n t was m a i n l y from t h e o r g a n i c f r a c t i o n . A l t h o u g h n o t v e r y s t r o n g , t h e h i g h e s t c o r r e l a t i o n c o e f f i c i e n t s between a v a i l a b l e P and o t h e r s o i l c h e m i c a l p r o p e r t i e s were f o r a v a i l a b l e P w i t h 0-5 cm C and C/m3. L i k e t h e p h y s i c a l p r o p e r t i e s , s o i l c h e m i c a l p r o p e r t i e s showed no s t a t i s t i c a l l y s i g n i f i c a n t r e s p o n s e t o t h e t y p e o f see d mix us e d . T h i s was t o be e x p e c t e d i n T r i a l 75.1 and on t r e a t m e n t s 70R and 70PF, where none o f t h e seed mixes p r o d u c e d s t r o n g g r o w t h . The growth o f agronomic s p e c i e s was much s t r o n g e r on 7OF and 7OP, and h e r e l a r g e d i f f e r e n c e s i n p l a n t g r o w t h r e s u l t e d i n some l a r g e d i f f e r e n c e s i n average s o i l v a l u e s on s e c t i o n s sown w i t h d i f f e r e n t seed mixes ( T a b l e 1.26). I n 1980, t h e h i g h e s t p l a n t g r o w t h was on p l o t s sown w i t h seed mix 5. T h i s r e s u l t e d i n t h e t h i c k e s t s u r f a c e o r g a n i c l a y e r and h i g h e s t c o n c e n t r a t i o n s o f C and N. N i t r o g e n was e s p e c i a l l y h i g h , as a r e s u l t o f t h e growth o f Table 1.26 Average data for soil chemical properties on sections of 70F and 70P sown with different seed mixes. Treat Depth pH %C C/m3 %N N/m3 avail.P avail.P/m3 C / N N / (kg/m3) (kg/m3) (ppm) (g/m3) avail.P 70F1 5-10cm 6.1 0.8 2.4 0.03 0.09 27 8.4 24 18 70F6 5-10cm 5.9 0.9 1.5 0.04 0.08 11 1.5 20 62 70F5 5-10cm 5.8 0.8 3.0 0.05 0.18 14 5.4 19 53 70P6 5-10cm 5.2 1.1 3.0 0.03 0.09 8 2.3 41 60 70P1 5-10cm 4.9 1.9 6.2 0.06 0.17 21 5.8 32 25 70F5 0-5cm 4.7 7.0 13.7 0.19 0.39 44 8.3 36 48 70P5 5-10cm 4.5 2.9 6.8 0.11 0.26 16 3.5 22 83 70F1 0-5cm 4.2 4.5 10.0 0.14 0.31 18 4.0 30 142 70P6 0-5cm 4.1 10.6 19.6 0.30 0.51 27 5.0 41 127 70F6 0.-5cm 4.1 3.7 6.4 0.17 0.28 31 5.0 24 56 70P5 0-5cm 4.1 14.5 23.5 0.52 0.63 29 4.8 27 184 70P1 0-5cm 4.0 1.2.3 30.8 0.28 0.67 30 7.4 44 94 108 b i r d s f o o t t r e f o i l ( L o t u s c o r n i c u l a t u s L . ) . The f a i l u r e o f t h e s e d i f f e r e n c e s t o be s t a t i s t i c a l l y s i g n i f i c a n t was due t o t h e g r e a t v a r i a b i l i t y i n t h e s o i l d a t a , w h i c h was a r e s u l t o f t h e g r e a t v a r i a b i l i t y i n p l a n t growth w i t h i n each t r e a t m e n t (see S e c t i o n 4.2). 109 4.1.3 Overburden O b s e r v a t i o n s o f p l a n t i n v a s i o n around t h e m i n e s i t e s u g g e s t t h a t t h e o v e r b u r d e n was a more h o s p i t a b l e medium f o r p l a n t g r o w t h t h a n t h e w a s t e r o c k . S i m i l a r l y on t h e T r i a l 70.1, p l a n t growth was more abundant and v i g o r o u s where an o r g a n i c r i c h o v e r b u r d e n had slumped o n t o t h e dump (70.OB). The p r o p o r t i o n and w e i g h t p e r m 3 o f p a r t i c l e s < 2 mm i n d i a m e t e r i n t h e o v e r b u r d e n were s i m i l a r t o t h o s e f o u n d i n t h e h o r n f e l s and p o t a s s i c w a s t e r o c k s ( T a b l e 1.27). However, OB.59 and b o t h d e p t h s o f 70.OB had l o w e r a v e r a g e b u l k d e n s i t i e s t h a n any o f t h e w a s t e r o c k a r e a x d e p t h c o m b i n a t i o n s . The l o w e r b u l k d e n s i t i e s o f t h e o v e r b u r d e n c a n be a t t r i b u t e d i n p a r t t o t h e i r h i g h ( v e r y h i g h f o r 7O.OB) o r g a n i c m a t t e r c o n t e n t . A n o t h e r r e a s o n was t h a t t r u c k s and b u l l d o z e r s , r a n o v e r t h e dump, c o m p a c t i n g t h e w a s t e r o c k . W h i l e t h e o v e r b u r d e n was s p r e a d by a backhoe. A backhoe was us e d f o r t h e f i e l d t r i a l s . However, i f o v e r b u r d e n i s t o be a p p l i e d on a l a r g e r s c a l e , a b u l l d o z e r p r o b a b l y w o u l d be used t o s p r e a d i t , and t h i s s h o u l d i n c r e a s e i t s b u l k d e n s i t y . Of t h e d i f f e r e n t o v e r b u r d e n t y p e s , OB.SH had t h e h i g h e s t b u l k d e n s i t y . OB.SH had a h i g h s t o n e c o n t e n t r e l a t i v e t o OB.59, and a low o r g a n i c m a t t e r c o n t e n t compared w i t h 7O.OB. M i n e r a l p a r t i c l e s i n OB.SH were d e r i v e d from h o r n f e l s r o c k , e x p l a i n i n g i t s low % < 2mm. Compared t o b o t h t h e w a s t e r o c k and t h e o t h e r o v e r b u r d e n t y p e s , t h e % < 2mm and b u l k d e n s i t y o f 70.OB were h i g h l y v a r i a b l e . T h i s was 110 Table 1.27 Soil properties of the overburden. < 2mm Site OB.SH 70.OB 70.OB OB.59 Depth 0.10cm 5-10cm 0-5cm 0-1 Ocm 15.(4) 20 (13) 30 (17) 30 (7) a a bede abedef def <2mm/m3 (kg/m3) 294 (126) bed 174 (75) abc 147 (51) a 373 (102) de Bulk Density (1000 kg/rr.3) 1.75 (.45) cde 1.23 (.58) ef 0.74 (.51) f 1.38 (.33) f Site OB.SH OB.59 70.OB 70.OB Depth 0-1 Ocm 0-10cm 5-10cm 0-5cm 6.5 4.3 (0.3) (0.3) 4.8 (1.6) 3.8 (0.5) f g .'•:* %C 2.3 (0.7) fg 1.9 (0.7) fg 12.4 (12.6) h 18.1 (11.8) h C/m3 (kg/m3) 6.21 (3.2) eg 7.80 (3.5) g 16.25 (12.1) gh 23.51 (10.7) gh Site . Depth %N OB.SH 0-1 Ocm 0.110 (0.010)g OB.59 0-10cm 0.090 (0.030) g 70.OB 5-1 Ocm 0.239 (0.193) gh 70.OB 0-5cm 0.381 (0.225) h N/m3 (kg/m3) 0.36 (0.11) ef 0.30 (0.09) ef 0.29 (0.19)ef C 5 0 (0.20) f available P (ppm) 6.3 (0.3) fi 8.2 (0.8) h (29.6) kl (7.5) I 38.1 33.1 Site OB.SH OB.59 70.OB 70.OB Depth 0-1 Ocm 0-1 Ocm 5-10cm 0-5cm available P/m3 (g/m3) (0.7) c (0.4) e f f 1.6 3.1 4.9 (2.4) 4.7 (1.6) C / N 20 (5) g 21 (15) g 43 (11) cdef 46 (3) cdef xC/xN N /available P 20 109 (44) abc 21 181 (26) abc 52 102 (83) abedef 47 110 (47) abc * : geometric mean xC/xN : mean %C / mean %N means followed by the same letter were not significantly different at p = 0.5 I l l p r o b a b l y due t o t h e wide v a r i a t i o n i n t h e t h i c k n e s s o f i t s s u r f a c e o r g a n i c l a y e r . Carbon and n i t r o g e n l e v e l s o f OB.SH and OB.59 were h i g h e r t h a n t h o s e o f 70R and l e s s t h a n t h o s e o f 70F. L e v e l s o f C, N, and a v a i l a b l e P i n 7O.OB were s i m i l a r t o t h o s e o f 70P. OB.59 and 70.OB were a c i d i c , h a v i n g pH v a l u e s s i m i l a r t o t h o s e f o u n d i n n a t u r a l s o i l s i n t h e a r e a . The h i g h pH o f OB.SH s u g g e s t e d t h e i n c l u s i o n o f unweathered, u n l e a c h e d r o c k . The h i g h o r g a n i c c o n t e n t and an a c t i v e b i o t a were t h e most l i k e l y r e a s o n s f o r t h e v i g o r o u s n a t u r a l p l a n t i n v a s i o n o b s e r v e d on t h e o v e r b u r d e n . H i g h e r c o n c e n t r a t i o n s o f N i n t h e o v e r b u r d e n a c c e l e r a t e t h e growth o f p l a n t s p e c i e s u n a b l e t o f i x N. An a c t i v e b i o t a ( e . g . , m y c o r r h i z a ) may make i m p o r t a n t c o n t r i b u t i o n s t o P a v a i l a b i l i t y . On t h e r e c e n t l y e xposed s t e r i l e w a s t e r o c k , P w i l l be a l i m i t a t i o n f o r g e r m i n a t i n g s e e d l i n g s u n a b l e t o r e l e a s e P from a p a t i t e . I n some c a s e s , a c c e l e r a t e d p l a n t c o l o n i z a t i o n r e s u l t e d from p l a n t p r o p a g u l e s a l r e a d y p r e s e n t i n t h e o v e r b u r d e n . Some o f t h e p l a n t g r o w t h on 70.OB ( e . g . , v a c c i n i u m ) p r o b a b l y r e s u l t e d from t h i s . However, many o f t h e e a r l y c o l o n i z e r s ( e . g . , w i l l o w ) were n o t p r e s e n t i n t h e s u r r o u n d i n g f o r e s t and a r r i v e d from o f f s i t e . O f f t h e w a s t e r o c k dumps, s u b s u r f a c e seepage c o n t r i b u t e s t o t h e s t r o n g growth o f p l a n t s e s t a b l i s h e d on t h e o v e r b u r d e n , and c o l o n i z a t i o n o f t e n f o l l o w e d seepage l i n e s . I n g e n e r a l , t h e d i s t u r b e d o v e r b u r d e n was v e r y s h a l l o w , 112 a l l o w i n g p l a n t s t o i n t e r c e p t d r a i n a g e t h a t c o l l e c t e d and f l o w e d a l o n g t h e b e d r o c k / s o i l i n t e r f a c e . However, when o v e r b u r d e n i s s p r e a d as a v e n e e r on t h e s u r f a c e o f a w e l l d r a i n e d dump, t h i s w i l l n o t o c c u r . 113 4.2 P l a n t Growth 4.2.1 G r a s s and Legume Growth on t h e Bench T r i a l s 4.2.1.1 T r i a l 70.1: Species/Amendment T r i a l 70.1 t e s t e d f o u r s u r f a c e t r e a t m e n t s and seven seed m i x e s . The seed mixes and f e r t i l i z e r r a t e s a r e l i s t e d i n T a b l e s 1.6 and 1.8. The f o u r s u r f a c e t r e a t m e n t s were a c o n t r o l (70R), f e r t i l i z e r ( 7 0 F ) , and two t r e a t m e n t s r e c e i v i n g p e a t (70P and 7 0 P F ) . No r e c o r d was k e p t o f t h e amount o f p e a t a p p l i e d . P e r c e n t c o v e r , biomass, and f o l i a r c h e m i s t r y were measured on t h e r e s u l t i n g g rowth. The v e g e t a t i v e c o v e r was measured i n 1980, 1981, and 1983, t h e 1 1 t h , 1 2 t h and 1 4 t h g r o w i n g s e a s o n s . The raw d a t a i s p r e s e n t e d i n A p p e n d i x C. The a v e r a g e moss, n a t i v e v a s c u l a r p l a n t , g r a s s , and legume c o v e r s f o r t h e m o n i t o r i n g p e r i o d a r e l i s t e d i n T a b l e 1.28. The g r a s s p l u s legume c o v e r f o r each t r e a t m e n t c o m b i n a t i o n i n 1971, 1972, and 1976 (from P r i c e , 1982) a r e a l s o i n c l u d e d . The a v e r a g e c o v e r o f i n d i v i d u a l v a s c u l a r p l a n t s whose c o v e r was g r e a t e r t h a n 0.5% i s g i v e n i n T a b l e 1.29. The p o o r e s t s u b s t r a t e f o r agronomic growth was t h e u n f e r t i l i z e d w a s t e r o c k (7OR). Clumps o f g r a s s f o u n d on 70R were s m a l l , c h l o r o t i c , and had few f l o w e r s . The o n l y n o t a b l e change i n t h e v e g e t a t i o n on t h i s t r e a t m e n t m o s t was t h e i n v a s i o n o f n a t i v e s p e c i e s . I n 1983, t h e c o v e r o f n a t i v e 114 Table 1.28 Average percent cover on different treatments in Trial 70.1 % Grass + Leg urne % Grass % Legume %lnv % Moss Treatment 71 72 76 80 81 83 80 81 83 80 81 83 83 81 83 70R1 12 6 1 3 2 1 3 2 tr tr 0 0 tr 6 12 70R2 11 6 1 3 tr 1 3 tr tr 0 tr tr 1 2 11 70R3 2 2 1 4 tr 1 4 tr tr 0 0 0 1 . 2 13 70R4 9 7 2 5 1 1 4 0 tr 1 1 tr tr 9 20 70R5 6 5 3 8 3 4 5 tr 1 4 3 2 1 6 22 70R6 12 19 3 7 2 3 6 1 1 1 1 1 1 15 27 70F1 72 77 48 40 19 4 36 14 2 5 4 2 tr 63 58 70F2 66 52 25 33 12 3 31 10 2 2 2 1 1 53 40 70F3 60 87 45 45 27 9 35 19 6 10 8 3 tr 64 66 70F4 42 66 18 24 9 9 18 4 4 6 4 3 1 59 47 70F5 24 65 58 63 53 50 29 17 11 34 36 39 0 72 80 70F6 64 83 34 32 20 12 21 9 4 11 12 8 tr 63 62 70P1 76 95 72 66 39 18 55 34 11 12 11 6 1 72 84 70P5 27 98 79 74 74 61 37 26 12 38 47 48 1 89 95 70P6 68 98 52 36 20 18 21 7 6 15 13 12 tr 91 92 70PF1 34 51 55 44 20 10 39 17 8 5 2 1 1 70 64 70PF5 5 18 25 22 13 10 13 5 2 9 7 7 1 32 41 70PF6 13 18 17 21 14 5 14 4 2 7 2 3 1 37 45 tr : 0.5-0.9% 71, 72, & 76 : from Price (1982) Inv : naturally invading vascular plants 115 Table 1.29 Average percent cover for individual agronomic species growing on Trial 70.1. Birdsfoot Alsike White Sainfoin Trefoil Clover Clover Treatment 81 83 81 83 81 83 81 83 70F1 1 tr 4 2 70F2 1 1 70F3 5 2 2 1 70F4 1 2 2 1 tr tr 70F5 35 37 1 1 1 1 70F6 8 5 3 2 70P1 7 4 2 tr 3 2 70P5 46 48 1 1 70P6 8 9 5 1 70PF1 1 . tr 1 1 70PF5 6 7 70PF6 3 1 2 1 Red Top Red Orchard Timothy Reed Canary Fescue Grass Grass Treatment 81 83 81 83 81 83 81 83 81 83 70F1 14 2 70F2 10 1 70F3 3 1 16 4 70F4 tr 1 2 1 2 1 70F5 3 1 3 2 4 2 2 1 6 5 70F6 6 3 1 1 1 1 70P1 34 11 70P5 3 2 19 10 3 0 1 1 70P6 2 2 4 3 1 tr 70PF1 17 8 70PF5 1 tr 5 2 70PF6 2 1 2 1 tr : 0.5-0.9% 116 v a s c u l a r p l a n t s exceeded 1% on a number o f t h e 7OR t r e a t m e n t c o m b i n a t i o n s . W h i l e s t r o n g e r t h a n on 70R, agronomic g r o w t h on t h e 70PF p e a t t r e a t m e n t was s i g n i f i c a n t l y l o w e r t h a n t h a t on 70P and 7OF. I n c o n t r a s t t o t r e a t m e n t s 7OF and 7OP, 70PF d i d n o t produce e i t h e r v i g o r o u s g r a s s growth o r s u s t a i n e d b i r d s f o o t t r e f o i l g r o w t h . The r e l a t i v e l y l a r g e c o v e r on 70PF1 p r o b a b l y r e s u l t e d from i t s p r o x i m i t y t o t h e 70P t r e a t e d p l o t s . A c c o r d i n g t o t h e o r i g i n a l t r i a l p l a n , t h e s u r f a c e t r e a t m e n t on t h e 70PF p l o t s was p e a t p l u s f e r t i l i z e r . W h i l e t h e c l o s e c o n t a c t between seed and f e r t i l i z e r o r e x c e s s a c i d i t y from a c i d i f i c a t i o n m i g h t a c c o u n t f o r t h e p o o r growth on f e r t i l i z e d p e a t , t h e s e t h e o r i e s do n o t a c c o u n t f o r t h e v i g o r o u s and abundant growth on t h e " s u p p o s e d l y " u n f e r t i l i z e d p e a t (7OP). P e a t from t h e same s o u r c e was used as a s u r f a c e t r e a t m e n t i n T r i a l 81.1 ( S e c t i o n 4.2.4.2). The p o o r agronomic c o v e r on 70PF was s i m i l a r t o t h e u n f e r t i l i z e d p e a t i n T r i a l 81.1, and t h e v i g o r o u s growth on t h e f e r t i l i z e d p e a t i n T r i a l 81.1 was more l i k e t h e 70P t r e a t m e n t . T h i s s u g g e s t s t h a t t h e 70P, r a t h e r t h a n t h e PF, t r e a t m e n t was f e r t i l i z e d . The t h e o r y t h a t p l a n t s g r o w i n g on p e a t r e q u i r e f e r t i l i z e r i s s u p p o r t e d by d a t a from o t h e r s t u d i e s . F o r i n s t a n c e , Maas (1972) s t a t e d t h a t f o r o r g a n i c s o i l s on Vancouver I s l a n d , " a l t h o u g h t h e l e v e l o f t o t a l n i t r o g e n i n an o r g a n i c s o i l may be t e n t i m e s as h i g h as i n a m i n e r a l s o i l , i t s a b i l i t y t o r e l e a s e a v a i l a b l e N i s q u i t e low. A t t h e same t i m e t h e i n i t i a l l e v e l s o f a v a i l a b l e P and e x c h a n g e a b l e K a r e a l s o low." I n Maas' (1972) 117 s t u d y t h e growth o f agronomic s p e c i e s was v e r y p o o r on u n f e r t i l i z e d p e a t s o i l s . Low a v a i l a b l e P l e v e l s and a h i g h C:N r a t i o i n s o i l samples c o l l e c t e d from t h e 70PF p l o t s s u g g e s t e d t h a t a f e r t i l i z e r a p p l i c a t i o n would improve growth. The low l e v e l s o f a v a i l a b l e P i n 70PF i n d i c a t e t h a t P f e r t i l i z e r had n o t been a p p l i e d . F o r a l l t h e f e r t i l i z e d w a s t e r o c k and t h e p e a t t r e a t m e n t s , e x c e p t 70F2, t h e agronomic c o v e r i n c r e a s e d from t h e 2nd t o t h e 3 r d g r o w i n g s e a s o n . The i n c r e a s e was most d r a m a t i c on p l o t s sown w i t h seed mix 5. From t h e 3 r d t o t h e 7 t h g r o w i n g s e a s o n , t h e c o v e r on a l l t h e t r e a t m e n t s d e c l i n e d . The d e c l i n e was g r e a t e s t on t h e g r a s s - d o m i n a t e d seed mixes (1,2,3,4 ,and 6 ) , and may be, a t l e a s t p a r t i a l l y , a t t r i b u t e d t o a d r o p i n t h e c o v e r o f v i g o r o u s s h o r t l i v e d s p e c i e s l i k e p e r e n n i a l r y e g r a s s . E x h a u s t e d f e r t i l i t y may a l s o have p l a y e d a r o l e . On t h e f e r t i l i z e d w a s t e r o c k , t h e d r o p i n s u r f a c e pH as a s u r f a c e l i t t e r l a y e r d e v e l o p e d may a l s o have r e d u c e d g r a s s g r o w t h . From t h e 7 t h t o t h e 1 1 t h g r o w i n g s e a s o n ( 1 9 8 0 ) , t h e agronomic c o v e r remained f a i r l y s t a b l e . D u r i n g t h e m o n i t o r i n g p e r i o d o f t h i s s t u d y ( t h e 1 1 t h , 12th,and 1 3 t h g r o w i n g seasons) t h e r e was a d e c l i n e i n t h e c o v e r on a l l t h e s e e d mixes dominated by g r a s s e s ( T a b l e 1.31). The d e c l i n e was p a r t i c u l a r l y s t r o n g on f e s c u e - d o m i n a t e d seed mix 1. A g a i n i n f e r t i l i t y and a d r o p i n pH were l i k e l y t h e c a u s e . I n f e r t i l i t y was s u g g e s t e d by t h e o b s e r v a t i o n t h a t t h e b e s t g r a s s g r o w t h o c c u r r e d b e s i d e o r w i t h i n b i r d s f o o t t r e f o i l 118 clumps. On 70F5 and 70P5, t h e d e c r e a s e i n g r a s s c o v e r was p a r t i a l l y compensated f o r by an i n c r e a s e i n t h e c o v e r o f b i r d s f o o t t r e f o i l . D u r i n g t h e m o n i t o r i n g p e r i o d b i r d s f o o t t r e f o i l was t h e o n l y agronomic s p e c i e s w h i c h i n c r e a s e d i t s c o v e r . Throughout t h e m o n i t o r i n g p e r i o d , t h e l a r g e s t agronomic c o v e r s were on t r e a t m e n t s 70F5 and 70P5. I n 1983, t h e c o v e r on t h e s e t r e a t m e n t s were, r e s p e c t i v e l y , 50% and 61%. The n e x t h i g h e s t c o v e r s , on 70P1 and 70P6, were o n l y 18%. The v i g o r o u s g r o w t h on 70F5 and 70P5 was a r e s u l t o f s u s t a i n e d s t r o n g b i r d s f o o t t r e f o i l g r o w t h . On e i t h e r t r e a t m e n t , b i r d s f o o t t r e f o i l a c c o u n t e d f o r o v e r 75% o f t h e c o v e r and, g i v e n i t s l a r g e bushy gr o w t h form, an even l a r g e r p r o p o r t i o n o f t h e a e r i a l b i o m a s s . I n 1983, presumably as a r e s u l t o f t h e addded N, 70F5 and 70P5 a l s o had t h e h i g h e s t g r a s s c o v e r . G r a s s e s were n o t i n c l u d e d i n seed mix 5. A l t h o u g h l e s s w i d e s p r e a d , v i g o r o u s g r a s s g r o w t h and l i t t e r p r o d u c t i o n were a l s o a s s o c i a t e d w i t h t h e growt h o f a number o f o t h e r legume s p e c i e s . A f t e r b i r d s f o o t t r e f o i l , t h e two commonest legumes were w h i t e and a l s i k e c l o v e r . The most v i g o r o u s g r o w t h o f w h i t e c l o v e r was on p l o t s sown w i t h seed mix 1, where i t was s c a t t e r e d amongst t h e f e s c u e swards. A l s i k e c l o v e r was a component o f seed mixes 3 and 6. The most common g r a s s e s were r e d f e s c u e and r e d t o p . Red f e s c u e was t h e dominant s p e c i e s on p l o t s sown w i t h seed mixes 1,2, and 3, w h i l e r e d t o p was t h e most common s p e c i e s on p l o t s sown w i t h seed mix 6. U n l i k e t h e o t h e r s p e c i e s w h i c h grew 119 s i n g u l a r l y o r i n clumps, r e d f e s c u e p r o d u c e d a dense matted t u r f - l i k e g rowth. The o n l y o t h e r abundant g r a s s e s d u r i n g t h e m o n i t o r i n g p e r i o d o f t h i s s t u d y , were o r c h a r d g r a s s , r e e d c a n a r y g r a s s , and t i m o t h y . These s p e c i e s have h i g h e r f e r t i l i t y r e q u i r e m e n t s t h a n r e d t o p and r e d f e s c u e (Watson e t a l . , 1980), and were g r o w i n g w e l l o n l y amongst t h e b i r d s f o o t t r e f o i l clumps. Even t h e r e , s t r o n g growth was i n f r e q u e n t . On a l l t h e s u r f a c e t r e a t m e n t x seed mix c o m b i n a t i o n s , p l a n t c o v e r was h i g h l y v a r i a b l e ( T a b l e 1.30). V a r i a b i l i t y was g r e a t e s t f o r i n d i v i d u a l s p e c i e s ( T a b l e 1.31). T h i s was e s p e c i a l l y t r u e f o r legumes l i k e a l s i k e c l o v e r , t h a t grew i n s c a t t e r e d clumps and had, i n many c a s e s , c o e f f i c i e n t s o f v a r i a n c e o v e r 200%. The d i s t r i b u t i o n o f g r a s s s p e c i e s tended' t o be l e s s v a r i a b l e . F o r a l l t r e a t m e n t c o m b i n a t i o n s , t h e c o v e r o f moss was g r e a t e r t h a n t h a t o f v a s c u l a r p l a n t s ( T a b l e 1.28). From h i g h e s t t o l o w e s t , t h e r a n k i n g o f s u r f a c e t r e a t m e n t s w i t h r e g a r d t o moss c o v e r was 70P > 70F = 70PF > 70R. On 70P, d i f f e r e n c e s i n moss c o v e r between s e e d mixes were much s m a l l e r t h a n d i f f e r e n c e s i n agronomic g r o w t h . S m a l l e r moss c o v e r on 70P1, compared t o 70P5 and 70P6, may be a t t r i b u t e d t o t h e c o m p e t i t i o n f o r space between moss and t h e m a t - l i k e clumps o f r e d f e s c u e . D e s p i t e t h e s t r o n g v a s c u l a r p l a n t g r o w t h , c o m p e t i t i o n f o r space d i d n o t appear t o be a p r o b l e m on 70F5 and 70P5. Most o f t h e b i r d s f o o t t r e f o i l f o l i a g e was q u i t e h i g h and t h e moss was a b l e t o grow u n d e r n e a t h i t . 120 Table 1.30 Coefficients of variance for different cover types in Trial 70.1 %Grass+Legume % Grass % Legume % Moss %lnv satment 80 81 83 80 81 83 80 81 83 81 83 83 70R1 107 172 144 105 172 65 54 70R2 103 122 103 112 72 152 70R3 98 85 98 78 76 . , 8 7 70R4 94 336 114 83 305 336 72 72 70R5 122 189 125 100 126 173 214 174 81 62 128 70R6 53 117 94 50 95 95 151 195 218 48 45 110 70F1 39 64 77 33 53 47 130 116 135 42 48 70F2 36 43 61 36 39 95 127 146 158 54 61 137 70F3 33 80 74 37 94 103 93 81 97 34 30 70F4 49 80 54 54 74 76 99 134 75 42 48 158 70F5 33 75 62 38 90 81 45 70 60 34 15 70F6 37 87 68 30 79 95 100 109 71 55 46 70P1 37 56 55 35 59 77 80 65 72 27 13 270 70P5 24 49 37 26 51 57 31 54 43 14 1 200 70P6 50 60 58 57 78 72 54 60 66 6 4 70PF1 59 95 101 61 107 124 107 110 112 23 31 112 70PF5 67 97 108 58 98 134 100 118 119 70 63 129 70PF6 68 77 60 78 68 67 99 191 86 33 58 123 Inv : naturally invading vascular plants 121 Table 1.31 Coefficient of variance for different grass and legume species growing on Trial 70.1. Birdsfoot Alsike White Sainfoin Trefoil Clover Clover Treatment 81 83 81 83 81 83 81 83 70F1 200 106 122 70F2 146 137 70F3 83 86 186 235 70F4 115 95 247 178 70F5 73 61 387 361 291 292 70F6 140 83 167 167 70P1 50 76 198 123 134 70P5 54 43 265 325 70P6 52 71 146 115 70PF1 159 123 125 70PF5 132 120 70PF6 190 146 45 89 Red Top Red Fescue Orchard Timothy Reed Canary Grass Grass Treatment 81 83 81 83 81 83 81 83 81 83 70F1 56 51 70F2 36 87 70F3 76 84 113 135 70F4 120 112 94 141 134 70F5 104 96 160 165 159 124 188 120 90 90 70F6 80 79 100 150 183 214 70P1 59 77 70P5 101 68 72 69 141 109 217 183 70P6 66 61 101 122 70PF1 108 128 70PF5 146 114 141 70PF6 65 60 116 106 122 R h a c o m i t r i u m canescens (Hedw.) B r i d . was t h e dominant c o l o n i z e r on t h e s t o n e y c o v e r o f 70R. Where some f i n e s o r l i t t e r a c c u m u l a t e d o r where t h e s u r f a c e was g r a v e l l y r a t h e r t h a n s t o n e y , t h e most common moss s p e c i e s was P o l v t r i c h u m  i u n i p e r u m Hedw. Where a dense o r g a n i c l a y e r had b u i l t up, p o l y t r i c h u m clumps were o f t e n mixed w i t h t h o s e o f o t h e r s p e c i e s ( e . g . , D r e p a n o c l a d u s aduncus and Aulacomnium p a l u s t r e (Hedw.) Schwaegr.). L i c h e n growth was o n l y found on a r e a s ( e . g . , 70R) l a c k i n g , a s u r f a c e o r g a n i c l a y e r . S i m i l a r t o t h e i n c r e a s e i n c o v e r o f moss from 1981 t o 1983 on t h e u n f e r t i l i z e d w a s t e r o c k , i n c r e a s e s were a l s o n o t e d f o r t h e l i c h e n . By t h e 1 5 t h season (1983), t h e c o v e r o f n a t i v e s p e c i e s i n v a d i n g t h e t r i a l s i t e had r e a c h e d 1% on more t h a n h a l f t h e s u r f a c e t r e a t m e n t x seed mix c o m b i n a t i o n s ( T a b l e 1.28). I n v a d i n g s p e c i e s i n c l u d e d a mix o f e a r l y s u c c e s s i o n a l s p e c i e s , l i k e w i l l o w , cottonwood, and f i r e w e e d , and s p e c i e s f o u n d i n t h e s u r r o u n d i n g f o r e s t , s u c h as hemlock, v a c c i n i u m , S i t k a s p r u c e , and b u n c h b e r r y (Cornus c a n a d e n s i s L . ) . The growth o f woody n a t i v e s p e c i e s i s d i s c u s s e d i n S e c t i o n 4.2.2.1. The above ground biomass was sampled i n 1980, 1981, and 1984. Raw d a t a f o r biomass w e i g h t i s g i v e n i n A p p e n d i x C. I n 1980, f o l i a g e was sampled a t t h e l o c a t i o n s as t h e s o i l s . The above ground b i o m a s s , s u r f a c e c o v e r , and some measures o f f o l i a r c h e m i s t r y a r e i n c l u d e d i n T a b l e 1.32. F o r 70F and 70P, u n l i k e t h e s o i l s d a t a , t h e r e were s i g n i f i c a n t d i f f e r e n c e s i n t h e f o l i a r biomass prod u c e d by d i f f e r e n t s e e d m i x e s . Table 1.32 Above ground biomass and foliar chemistry data from Trial 70.1 in 1980. Treatment Biomass (g/m2) % Legume % Grass R 7 (5) a 0 (0) a 1 (1) a PF 27 (25) b 1 ID a 8.(9) be F16 33 (18) b 5 (5) a 9 (10) be P16 53 (40) b 1 (2| • a 20 (27) c P5 213 (100) c 38 (24) b 7 (7) ab F5 390 (386) c 51 (39) b 2 (2) a Treatment %N %P %K R 1.06 (0.50) be 0.096 (.043) b 0.54 (0.24) b PF 0.72 (0.20) a 0.086 (.026) a 0.47 (0.17) a F16 1.37 (0.59) c 0.111 (.016) be 0.83 (0.27) be P16 0.93 (0.31) b 0.112 (.024) c 0.78 (0.34) be P5 2.07 (0.40) c 0.132 (.025) c 1.17 (0.10) c F5 2.02 (0.18) c 0.095 (.026) ab 1.08 (0.33) c 7 (9) : average (standard deviation) means followed by the same letter were not significantly different at p = 0.5 124 D i f f e r e n c e s were between t h e legume-dominated seed mix 5 and t h e g r a s s - d o m i n a t e d seed mixes 1 and 6. As a r e s u l t , f o r 7OF and 70P, biomass d a t a from seed mix 5 was t r e a t e d s e p a r a t e l y , w h i l e d a t a f o r seed mixes 1 and 6 were combined. On 7OR and 70PF t h e r e were no s i g n i f i c a n t d i f f e r e n c e s i n among seed m i x e s , so t h e d a t a from d i f f e r e n t seed mixes were combined. As e x p e c t e d from i t s s m a l l p l a n t c o v e r , 70R had a s i g n i f i c a n t l y l o w e r f o l i a r biomass w e i g h t t h a n a l l t h e o t h e r t r e a t m e n t s . Next l o w e s t were 70PF, 70F16, and 70P16, none o f w h i c h were s i g n i f i c a n t l y d i f f e r e n t , a l t h o u g h t h e a v e r a g e biomass on 70PF was a l m o s t h a l f t h a t on 70P16. Biomass w e i g h t s from 70F5 and 70P5 were s i g n i f i c a n t l y h i g h e r t h a n a l l t h e o t h e r t r e a t m e n t s . The biomass samples t a k e n o f i n d i v i d u a l samples i n 1981 c o n f i r m e d t h a t t h e s t r o n g p l a n t g r o w t h from seed mix 5 was a r e s u l t o f v i g o r o u s b i r d s f o o t t r e f o i l growth ( T a b l e 1.33). F i f t e e n s easons a f t e r t h e t r i a l was e s t a b l i s h e d , b i r d s f o o t t r e f o i l s t i l l p r o d u c e d y i e l d s o f 3000 t o 4000 kg biomass/ha, y i e l d s as l a r g e as t h e b e s t g r o w t h on r e c e n t l y f e r t i l i z e d t r e a t m e n t s i n o t h e r t r i a l s ( T a b l e 1.34). L i k e t h e p l a n t c o v e r d a t a , t h e biomass p r o d u c t i o n w i t h i n t r e a t m e n t s was h i g h l y v a r i a b l e ( T a b l e 1.34). A l m o s t a l l t h e t r e a t m e n t s had c o e f f i c i e n t s o f v a r i a t i o n g r e a t e r t h a n 50%. Many were more t h a n 100%. The most v a r i a b l e g r o w t h was on 70F5. A l t h o u g h t h e a v e r a g e biomass on 70F5 was much l a r g e r t h a n on P5, due t o t h e h i g h v a r i a b i l i t y on 70F5, t h e two t r e a t m e n t s were 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 . 125 Table 1.33 Above ground biomass of species sampled in Trial 70.1 in September, 1981. Above Ground Biomass (g/m2) Species 70R 70F 70P 70PF Red Fescue 43 74 117 141 Alsike Clover 73 229 90 98 Birdsfoot Trefoil 13 257 397 98 Table 1.34 Above ground biomass of agronomic species in trials in September, 1984. Above Ground Biomass (g/m2) Trial Treatment # Mean Std Dev Species 70.1 70F5 4 389 263 birdsfoot trefoil 70P5 4 374 64 birdsfoot trefoil 81.1 Peat+Fert. 12 383 169 grass + legume 82.1 WR 8 308 106 mainly grass OBSH.10 8 195 66 mainly grass OBSH.30 8 98 '49 mainly