Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
DSpace
UBCV
Adams, Rupert Spencer
Master of Science - MSc
University of British Columbia
Howe Sound, a glacial fjord situated between Vancouver and Squamish, British Columbia, is subject to a semi-restricted, estuarine type flow regime that results in easily quantifiable sources for the organic matter present in the sediments. Therefore, it was chosen as an ideal location to examine the effects of sediment surface area on the preservation of organic matter and industrial pollutants in the paralic environment. A variety of surface sediment and core samples were retrieved and analyzed for organic content and surface area, as well as other sediment biomarkers and organic pollutant concentration. The role of sediment surface area as a key factor in the preservation of organic matter in marine sediments was then assessed both on historical and geological time-scales, in terms of its potential for generating petroleum source rocks. Organic carbon content of sediments within the study area ranges from 0.1-11 wt.%; a carbon/total nitrogen ratio (C[sub org]/N) of 6-24 in conjunction with other sediment parameters such as δ¹³ C[sub org] and electron microscopy, confirmed a dominant terrestrial signature for the organic fraction of the sediments collected. Sediment surface area varies between 0.5-22 m²/g depending on sample type, location, depth and grain size distribution. Good correlation between surface area and organic carbon in bulk sediments and size fractionated sediments suggests that organic matter is adsorbed to mineral grain surfaces. Correlation between dioxins, furans and surface area varies from r² = 0.23-0.54 in bulk samples, up to r²=0.99 in size fractionated sediments, suggesting that organochlorine pollutant concentration is also linked to sediment surface area. Mineralogy and elemental composition did not appear to correlate with TOC concentration, but additional factors such as molecular chlorination and sample depth did appear to influence the correlation between organochlorine pollutants and surface area. However, in all cases sediment surface area appeared to be the primary factor that governed the preservation of organic matter and industrial pollutants within the study area.
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AN EXAMINATION OF THE ROLE OF SEDIMENT SURFACE AREA IN CONTROLLING THE PRESERVATION OF ORGANIC MATTER IN A PARALIC ENVIRONMENT AND ITS INFLUENCE ON PETROLEUM SOURCE ROCK FORMATION AND CONTAMINANT ADSORPTION, HOWE SOUND, BRITISH COLUMBIA by Rupert Spencer Adams B.Sc, The Royal School of Mines, Imperial College of Science, Technology and Medicine, London University, 1997 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE STUDIES (Department of Earth and Ocean Sciences) We accept this thesis as conforming to the requiredjstandard THE UNIVERSITY OF BRITISH COLUMBIA April 2003 © Rupert Spencer Adams, 2003 In presenting this thesis in partial fulfillment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or b y 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 A b s t r a c t Howe Sound, a glacial fjord situated between Vancouver and Squamish, British Columbia, is subject to a semi-restricted, estuarine type flow regime that results in easily quantifiable sources for the organic matter present in the sediments. Therefore, it was chosen as an ideal location to examine the effects of sediment surface area on the preservation of organic matter and industrial pollutants in the paralic environment. A variety of surface sediment and core samples were retrieved and analyzed for organic content and surface area, as well as other sediment biomarkers and organic pollutant concentration. The role of sediment surface area as a key factor in the preservation of organic matter in marine sediments was then assessed both on historical and geological time-scales, in terms of its potential for generating petroleum source rocks. Organic carbon content of sediments within the study area ranges from 0.1-11 wt.%; a carbon/total nitrogen ratio (Corg/N) of 6-24 in conjunction with other sediment parameters such as 8 1 3C o r g and electron microscopy, confirmed a dominant terrestrial signature for the organic fraction of the sediments collected. Sediment surface area varies between 0.5-22 m /g depending on sample type, location, depth and grain size distribution. Good correlation between surface area and organic carbon in bulk sediments and size fractionated sediments suggests that organic matter is adsorbed to mineral grain surfaces. Correlation between dioxins, furans and surface area varies from r2 = 0.23-0.54 in bulk samples, up to r2=0.99 in size fractionated sediments, suggesting that organochlorine pollutant concentration is also linked to sediment surface area. Mineralogy and elemental composition did not appear to correlate with TOC concentration, but additional factors such as molecular chlorination and sample depth did appear to influence the correlation between organochlorine pollutants and surface area. However, in all cases sediment surface area appeared to be the primary factor that governed the preservation of organic matter and industrial pollutants within the study area. ii Table of Contents Abstract ii Table of Contents iii List of Tables vi List of Figures vii Acknowledgements x CHAPTER 1: Overview, 1 1.1. Introduction: 1 1.2. The Nature of Surface Area: 1 1.3. Organic Matter Preservation in Sediments: 2 1.4. Thesis Profile: 4 1.5. References: : 5 CHAPTER 2: The Effects of Surface Area, Grain Size and Mineralogy on Organic Matter Sedimentation and Preservation Across the Modern Squamish Delta, British Columbia: The Potential Role of Sediment Surface Area in the Formation of Petroleum Source Rocks 7 2.1. Abstract: 7 2.2. Introduction: 8 2.2.1. Study Area: 12 2.2.2. Sedimentology: 12 2.3. Methods: 1 4 2.3.1. Sample Collection: I 4 2.3.2. Sediment Size Fractionation: I 4 2.3.3. Elemental Analysis: 15 2.3.3.1. Organic Carbon and Nitrogen: 15 2.3.3.2. Inorganic Carbon: 15 2.3.4. Major and Minor Elements: 15 2.3.5. 5 ,3C: 1 6 2.3.6. Surface Area: 16 2.3.7. Mineralogy and Petrography: 16 2.4. Results: I 7 2.4.1. Bulk Analysis: 17 2.4.1.1. C and N Distributions: .' 17 2.4.1.1.1. Bulk Sediments: 17 2.4.1.1.2. Size Fractionated Sediments: 20 2.4.1.2. Surface Area Trends: 26 2.4.1.2.1. Bulk Sediments: 26 2.4.1.2.2. Size Fractionated Sediments: 26 2.4.1.3. 513C: 29 2.4.1.4. Mineralogy and Geochemistry: .30 2.4.1.4.1. Mineralogy: 31 2.4.1.4.2. Elemental Geochemistry: 31 2.5. Discussion: 32 2.5.1. Organic Matter Distribution: 32 2.5.2. Surface Area: A Mechanism for Petroleum Source Rock Formation: 33 2.5.3. Implications for Petroleum Geology: 35 2.6. Conclusions: .36 2.7. Acknowledgements: 38 2.8. References: .39 CHAPTER 3.The Environmental Significance of Sediment Surface Area as a Controlling Factor in the Preservation of Polychlorinated Dibenzo-p-Dioxins and Dibenzofurans (PCDD/PCDF) in Sediments Adjacent to the Woodfibre Pulp Mill, Howe Sound, British Columbia 42 3.1. Abstract: .42 3.2. Introduction: 43 3.2.1. Project Synopsis: 45 3.3. Methods: 45 3.3.1. Sampling: 45 3.3.2. Sediment Fractionation: 47 3.3.3. Elemental Analysis: 49 3.3.3.1. Organic Carbon and Nitrogen: .49 3.3.3.2. Inorganic Carbon: .49 3.3.4. Organochlorine Analysis: 49 3.3.4.1. Sample Extraction, Cleanup and Fractionation: 49 3.3.4.2. Instrument Analysis and Quantification: 52 3.3.5. Surface Area: 54 3.3.6. 210Pb Dating: 54 3.4. Sediment Core Age Profile: 55 3.5. Results: 56 3.5.1. Bulk Organic Analysis: 56 3.5.1.1. Elemental Composition: 56 3.5.1.1.1. Carbon and Nitrogen Content: 56 3.5.1.1.2. Organic Carbon/Nitrogen Ratio: 56 3.5.1.2. Organochlorine Compounds: .56 3.5.1.2.1. PCDD/Fs: 56 3.5.1.3. Surface Area: 64 3.5.1.3.1. PCDD/Fs and Surface Area: 64 3.5.2. Size Fractionated Organic Analysis: 68 3.5.2.1. Elemental Composition: 68 3.5.2.1.1. Carbon and Nitrogen Content: 68 3.5.2.1.2. Organic Carbon/Nitrogen Ratio: 71 3.5.2.2. Surface Area: .71 3.5.2.3. Organochlorine Compounds: 74 3.5.2.3.1. PCDD/Fs: 74 3.5.2.3.1.1. DF 14-16: 74 3.5.2.3.1.2. DF 20-22: 77 3.5.2.3.1.3. DF 34-36: 77 3.5.2.3.1.4. DF 46-48: 79 3.5.2.3.2. PCDD/Fs and Surface Area: 82 3.5.2.3.2.1. DF 14-16: 83 3.5.2.3.2.2. DF 20-22: 83 3.5.2.3.2.3. DF 34-36: 86 3.5.2.3.2.4. DF 46-48: 86 3.5.2.3.3. PCDD/Fs and Organic Matter: 87 3.6. Discussion: 90 3.7. Conclusions: 97 3.8. Acknowledgements: 100 3.9. References: 101 CHAPTER 4: Conclusions 106 4.1. Conclusions: 106 4.2. References: HO CHAPTER 5: Appendices 112 5.1 Appendix A: Major and Minor Element Concentration Data 112 5.2 Appendix B: PCDD/F Concentration Data 117 v List of Tables Table 1: TOC, TN, Corg/N and surface area (SA) for bulk surface sediment samples from the Squamish Delta, and from secondary core locations in Howe Sound 18 Table 2: TOC, TN, Corg/N and surface area (SA)for the <25jUm, 25-53/Jm, 53-I06/Mn and 106-250[Jm size fractions from the Squamish Delta 22 Table 3: bi3C data for selected bulk and size fractionated (jam) samples from the Squamish Delta and secondary core locations in Howe Sound 30 Table 4: Composition of internal standard surrogate mixtures used to spike all samples analysed 57 Table 5: Polychlorinated Dibenzo-p-dioxins (PCDDs) and Polychlorinated Dibenzo-p-furans (PCDFs) determined in each sediment sample analyzed 53 Table 6: Organic Carbon (Corg), Total Nitrogen (TN), Carbon/Nitrogen Ratio (Corg/N) and Surface Area (SA) for bulk sediment samples from the core taken adjacent to Woodfibre pulp Mill, Howe Sound, British Columbia, subsampled every centimetre for the first ten centimetres and every two centimetres thereafter 57 Table 7: Homologue and total homologue (PCDD, PCDF) concentration (pg/g) for dioxins and furans in bulk sediment samples from selected depth intervals 62 Table 8: Organic Carbon (Corg), Total Nitrogen (TN), Carbon/Nitrogen Ratio (Corg/N) and Surface Area (SA) for sediment samples from selected depth intervals, size fractionated into five fractions: <2pJn, 2-W/Jm, 10-20pM, 20-63pm and >63jUm 69 Table 9: Homologue and total homologue (PCDD, PCDF) concentration (pg/g) for dioxins and furans, in selected size fractionated sediment samples 75 Table 10: r2 values for dioxin/furan/total homologue concentration (pg/g) vs. surface area (rn/g). Negative values indicate a negative correlation between the two parameters. The number of size fractions indicates how many data points were used to generate the regression coefficient; r2 values using four' size fractions exclude the >63ptm fraction from the calculation, r values using five' size fractions include all the fractions 85 v i List of Figures Figure 1: Surface area vs. TOC for bulk surface sediment samples from continental shelf regions around the world (n = 68). Diagonal bars represent the monolayer equivalent zone as defined by the 95% confidence interval from down core refractory background data from North American shelf sites. (Modified from Mayer, 1994a) 10 Figure 2: Map of Howe Sound, British Columbia, showing the locations of the grab sample field (SD 1-25) on the Squamish Delta, and core samples (26-34, Cl, C2, C3, Woodfibre Pulp Mill and Port Mellon Pulp Mill) 13 Figure 3: TOC distribution across the Squamish Delta, for bulk sediment samples. The subsurface channel on the western side of the delta is marked by low TOC concentrations, with higher TOC concentrations found in peripheral areas 19 Figure 4: Distribution of A) TOC and B) TN across the Squamish Delta for the <25 pun, 25-53pjn, 53-106pm and 106-250jLtm size fractions 21 Figure 5: TOC distribution across the Squamish Delta, for the <25pm size fraction. The highest concentrations occur on the western side of the delta 24 Figure 6: TOC vs. TN showing the C/N ratio for size fractionated sediments. The 106-250pjn fraction is carbon rich relative to the other size fractions and has a different regression trend 25 Figure 7: A) TOC vs. surface area for bulk sediment samples taken from across the Squamish Delta (n = 25); B) TOC vs. surface area for bulk sediment samples taken from across the Squamish Delta. Selected samples only (n -23) 2 7 Figure 8: A ) TOC vs. surface area for size fractionated sediments from the Squamish Delta; B) TOC vs. surface area for size fractionated sediments from the Squamish Delta. The < 2pjn fraction has been omitted 28 Figure 9: Map showing the location of the sample site in Howe Sound, British Columbia, Canada 46 Figure 10: Mass distribution (%) of three samples, used to select grain size classes for analyses on size fractionated sediments 48 Figure 11: Downcore variations in Organic Carbon (Corp A) and Total Nitrogen (B) for bulk sediment samples. Note the sawtooth profile with no consistent downcore trend 58 Vll Figure 12: Downcore variation in Organic Carbon/Total Nitrogen ratio (Corg/N). The trend line depicts a gradual increase in Corg/N ration with increasing sediment depth 59 Figure 13: Plot of Organic Carbon (Corg) vs. Total Nitrogen (TN) for bulk sediment samples. A positive correlation exists between the two parameters, modeled by a linear regression (r2 = 0.7) 60 Figure 14: Downcore variation in Total Polychlorinated Dibenzo-p-dioxin (PCDD; A) and Total Polychlorinated Dibenzo-p-furan (PCDF; B) for bulk sediment samples 61 Figure 15: Downcore variation in dioxin homologue concentration for bulk sediment samples. Inset shows HxCDD, which is present at significantly higher concentrations than the other homologues 63 Figure 16: Downcore variation in furan homologue concentration for bulk sediment samples. Inset shows TCDF, which is present at significantly higher concentrations than the other homologues 65 Figure 17: Plot of Surface Area (SA) vs. Organic Carbon (Corg) for bulk sediment samples, showing a moderate positive linear regression, r2 = 0.4 66 Figure 18: Plot of Surface Area (SA) vs. dioxin, furan and total homologue concentration for bulk sediment samples 67 Figure 19: Distribution of Organic Carbon (Corg; A) and Total Nitrogen (TN; B) for four selected samples, size fractionated into five fractions: <2pyn, 2-10fim, 10-20pm, 20-63jum and >63pm 70 Figure 20: Plot of Organic Carbon (Corg) vs. Total Nitrogen (TN) for size fractionated samples. Note, the >63pm fraction falls on a separate regression (r2 = 0.6) than the other four fractions (r2 = 0.8) 72 Figure 21: A) Plot of Surface Area (SA) vs. Organic Carbon (Corg)for size fractionated samples. The >63pm fraction plots to the right of the graph due to its high Corg content and low surface area. B) Plot of surface area and Corg for size fractionated samples with the >63pm fraction removed. The plot has a moderate positive correlation, r2 = 0.5 73 Figure 22: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 14-16cm depth interval. The overall trend is of decreasing concentration with progressively finer grain size 76 V l l l Figure 23: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 20-22cm depth interval. Peak concentrations occur in the coarsest fraction. Dioxin concentration increases in the finest two size fractions, whilst furan concentration remains relatively constant throughout 78 Figure 24: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 34-36cm depth interval. Peak concentrations occur in the coarsest fraction. Some dioxin and furan homologues increase in concentration in the finest two size fractions, whilst other homologues show steady decrease in concentration 80 Figure 25: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 46-48cm depth interval. The majority of dioxin and furan homologues show significant increase in concentration in the finest three fractions. Insets show homologues present at concentrations significantly higher than other homologues 81 Figure 26: A-J) Selected plots of Surface Area (SA) vs. homologue concentration for size fractionated sediments from the 14-16cm, 20-22cm, 34-36cm and 46-48cm depth intervals 84 Figure 27: A) Plot showing the correlation between dioxin and furan concentration and organic matter concentrations in size fractionated sediments. Inset plots are those congeners with concentrations that are significantly higher than other congeners 88 Figure 27: B) Plot of dioxin and furan concentration vs. organic matter concentration with the >63 pm fraction removed. Note the increase in r value for HxCDD through OCDD dioxin and the decrease in r2 value for TCDD and PeCDD 89 IX Acknowledgements I would like to thank my supervisor, Professor R. Marc Bustin, whose steadfast support, sound advice and deep pocket made this research possible. I also thank my other committee members, Professors Steve Calvert and Ken Hall. Steve's knowledge on geochemical and oceanographic issues was invaluable, whilst Ken's initial ideas on environmental issues got the second half of my thesis off the ground. I must also thank the unsung heroes from the basement of the geology building: Bryon Cranston and Mike St. Pierre for their help in obtaining equipment and supplies in the shortest possible time, Mark Baker for his computer wizardry and sarcastic whit, and Ray Rodway and Doug Poison for their expertise in machine shop. In oceanography, I thank Maureen Soon who taught me a great deal about chemical analyses, and without whose help my results would probably be meaningless! I must also not forget Ram, who captained the boat on many a sample trip in Howe Sound, and who almost got tangled up in the boat's winch.. .thanks for putting your life on the line for a good core! Finally, but by no means least, I thank my family, Claudine, Jake and Kobe; their patience and support has been invaluable over what has turned out to be a very long haul. x C H A P T E R 1: Overview 1.1. Introduction: The world's oceans and sediments therein represent the final repository for much of the terrestrial detritus derived from weathering and erosion, atmospheric fallout of particulate material, industrial (man-made) byproducts, as well as all marine life and inorganic precipitates. The result is a highly variable sedimentary matrix that can contain a variety of inorganic and organic components, which are often sourced from multiple areas. Not only can the type and amount of these sedimentary components change, but also the ratio between them, which will ultimately reflect the geographical location of the sediment and its sources. There is also a temporal component to marine sediments, as sources and accumulation rates can, and do, change on a variety of time scales from months to hundreds of years. The resulting diversity achieved through the interaction of these variables results in physical and chemical properties that are unique to a given sediment e.g. mineralogy, elemental composition, organic content, grain size, sorting, surface area, porosity, pore water chemistry and redox conditions. This thesis examines a number of these sediment properties in samples collected from Howe Sound, a coastal fjord in south-east British Columbia, but focuses specifically on sediment surface area and the implications of adsorption of organic matter onto mineral grain surfaces, which is thought to be the main mechanism by which organic matter is preserved in sedimentary rocks in the geological record. 1.2. The Nature of Surface Area: The concept of surface area adsorption was developed to explain the uptake of various gases into porous solids, a phenomenon that was first observed by Fontana in 1777 (Gregg and Sing, 1982). The term adsorption was originally defined by Kayser in 1881, who used the term to refer to the condensation of gases on free surfaces of a porous 1 solid (Gregg and Sing, 1982). Adsorption, or more specifically physical adsorption, is now defined as the enrichment or depletion of one or more components in an interfacial layer (IUPAC Manual of Symbols and Terminology, 1972), in contrast to absorption, which refers to the incorporation of gases directly into the mass of the solid (Gregg and Sing, 1982). The forces involved in adsorption of gas to the surface of a solid are classified as physical or chemical. Physical adsorption refers to gases bound to surfaces via forces generated by the interaction of atoms in close proximity to one another (Clarkson, 1994). Chemical adsorption refers to electrostatic attraction between the adsorbate (the gas) and the adsorbent (the porous solid onto which gas is adsorbed; Clarkson, 1994). These forces can act alone or in combination, depending on the nature of the adsorbate and adsorbent in question (Clarkson, 1994). In marine sediments, the inorganic component of the sediment i.e. the mineral grains, can be thought of as the adsorbent. Although in most cases, minerals are not porous and do not possess 'internal' surface area, the external surfaces of minerals can be extensively grooved and pitted which can result in high surface areas. The exception to this is clay minerals, which have interlamellar sites that can be considered as internal surfaces. Interlamellar sites are usually on the order of 1-2 A°, and are not measured by gas adsorption techniques using N2, which is the common adsorbate used in sediment surface area measurements (Mayer, 1994). Sediment surface area, which can range from <1 m2/g in silty and sandy sediments to values as high as 50 m2/g in clay rich sediments (Mayer, 1994), is fundamental in understanding how organic matter, which can easily be remineralized by bacterially mediated breakdown, is preserved in marine sediments. 1.3. Organic Matter Preservation in Sediments: Organic matter (OM) in sediments can be crudely classified into marine OM, that which was produced within the world's oceans, and terrestrial OM, which includes material from soils and plant biomass. Marine sediments contain about 0.0002% of the total carbon in the Earth's crust (Hedges and Keil, 1995). Overall, terrestrial OM constitutes about 0.003% of the total, compared to marine OM, which contributes 2 approximately 0.0008% (Hedges and Keil, 1995). The vast majority of organic carbon (OC) is found as kerogen in sedimentary rocks (approx. 20% of total organic carbon in the earths crust); thus, preservation of OM in marine sediments is an important process in determining the organic content of sedimentary rocks in the geological record. The factors that affect OM burial and preservation in marine sediments are numerous, including bulk sedimentation rate, OM source, type and composition, redox conditions within the sediments and overlying water column (Calvert et al, 1996) and sediment surface area (Mayer, 1994; Hedges and Keil, 1995). Exactly how sediment surface area and OM concentration in sediments are linked together is still the subject of intense scientific scrutiny. The original theory that fine-grained sediments contained high OC concentrations due to the hydrodynamic equivalence between OM and fine-grained inorganic minerals has now been replaced with the concept that high OC concentrations are the direct result of the high surface areas of phyllosilicate minerals that dominate fine-grained sediments (Mayer 1994, 1999; Hedges and Keil, 1995; Bergamaschi et al, 1996). The positive correlation between OC content and sediment surface area was first observed by Suess (1973), who reported the phenomenon in shallow water calcitic sediments. There are two main theories describing how OM is bound to particle surfaces. The first is that OM is present in the form of a thin veneer or 'monolayer' that covers the whole grain. This theory is supported by data from Mayer (1994) and Keil at al (1994) who suggest a range of 0.5-1.0 mg OC/m2, which represents the typical range for OC loading on mineral surfaces in marine sediments assuming an even distribution of moderately sized organic molecules across the whole surface. Loadings that exceed this range (super-monolayer) and loadings that fall beneath the range (sub-monolayer) are also documented and occur in specific marine environments (Hedges and Keil, 1995). Mayer (1994) documents that higher loadings at the top of sediment cores often decrease down core to monolayer equivalent values, suggesting that only a certain portion of OM is recalcitrant enough to be preserved. The alternative theory is that OM is not evenly distributed across mineral surfaces as a monolayer, but rather as discrete patches associated with surface pits and grooves on the mineral surface (Ransom et al, 1997; Mayer, 1999), or in the case of clay minerals, on 3 the edge sites of the grains (Kubicki et al, 1997). This theory lends credibility to the idea that OM is protected from enzymatic attack and subsequent remineralization when it is adsorbed to the surface of a mineral, because hydrolytic enzymes are too large to penetrate the surface pits that house the OM. Mayer (1994, 1999) showed that the average size of these surface pits was <10 nm which corresponds to fine grained mesopores (2-50 nm). The proportionality that exists between surface area and OC concentration (Bergamaschi et al, 1996; Hedges and Keil, 1995; Keil at al, 1994; Mayer 1994, 1999), suggests that surface area is a crucial factor in preserving OM in sediments and thus in the geological record, although the exact nature of the association between the two is still not fully understood. 1.4. Thesis Profile: The next two chapters of this thesis examine the concepts discussed above and expand on the implications of surface area adsorption of OM in the paralic environment. The second chapter focuses on surface area as a mechanism to explain the formation of deltaic petroleum source rocks characterized by low OC contents, whilst the third chapter looks at the potential of sediment surfaces for adsorbing chlorinated organic pollutants sourced from coastal industry. 4 1.5. References: • Bergamaschi, B.A., Tsamakis, E., Keil, R.G., Eglinton, T.I., Montlucon, D.B., Hedges, J.I. (1997): The effect of grain size and surface area on organic matter, lignin and carbohydrate concentration, and molecular compositions in Peru Margin sediments. Geochimica et Cosmochimica Acta, Vol. 61, No. 6, pp. 1247-1260. • Calvert, S.E., Bustin, R.M., Ingall, E.D. (1996): Influence of water column anoxia and sediment supply on burial and preservation of organic carbon in marine shales. Geochimica et Cosmochimica Acta, Vol. 60, No. 9, pp. 1577-1593. • Clarkson, R. C. (1994): The effect of coal composition upon gas sorption and transmissibility of bituminous coal. Masters Thesis, University of British Columbia. • Fontana, F. (1777). Memorie Mat. Fis. Soc. Ital. Sci. I, pp. 679. • Gregg, S. J., Sing, K. S. W. (1982): Adsorption, Surface Area and Porosity. Second Ed., Academic Press. • Hedges, J.I., Keil, R.G. (1995): Sedimentary organic matter preservation: an assessment and speculative synthesis. Mar. Chem. Vol. 49, pp. 81-115. • IUPAC Manual of Symbols and Terminology, Appendix 2, Pt. 1, Colloid and Surface Chemistry. Pure Appl. Chem., Vol. 31, pp. 578. • Kayser, H. (1881). Wied. Ann., Vol. 14, pp. 451. • Keil, R. G., Tsamakis, E., Bor Fuh, C , Giddings, J. C, Hedges, J. I. (1994): Mineralogical and textural controls on the organic composition of coastal marine sediments: Hydrodynamic separation using SPLITT-fractionation. Geochimica et Cosmochimica Acta, Vol. 58, No. 2, pp. 879-893. • Kubicki, J. D., Itoh, M. J., Schroeter, L. M., Apitz, S. E. (1997): Bonding mechanisms of salicylic acid adsorbed onto illite clay: An ATR-FTIR and molecular orbital study. Env. Sci. Tech., Vol. 31, pp. 1151-1156. • Mayer, L.M. (1994): Surface area control of organic carbon accumulation in continental shelf sediments. Geochimica et Cosmochimica Acta, Vol. 58, No. 4, pp. 1271-1284. • Mayer. L.M. (1999): Extent of coverage of mineral surfaces by organic matter in marine sediments. Geochimica et Cosmochimica Acta, Vol. 63, No. 2, pp. 207-215. 5 • Ransom, B., Bennett, R.J., Baerwald, R., Shea, K. (1997): TEM study of in situ organic matter on continental shelf margins: occurrence and the "monolayer" hypothesis. Mar. Geol. Vol. 138, pp. 1-9. • Suess, E. (1973): Interaction of organic compounds with calcium carbonate-II. Organo-carbonate association in recent sediments. Geochimica et Cosmochimica Acta, Vol. 37, pp. 2435-2447. 6 C H A P T E R 2: THE EFFECTS OF SURFACE AREA, GRAIN SIZE AND MINERALOGY ON ORGANIC MATTER SEDIMENTATION AND PRESERVATION ACROSS THE MODERN SQUAMISH DELTA, BRITISH COLUMBIA: THE POTENTIAL ROLE OF SEDIMENT SURFACE AREA IN THE FORMATION OF PETROLEUM SOURCE ROCKS 2.1. Abstract: Surface sediment samples were collected from the Squamish River Delta, British Columbia, in order to determine the role of sediment surface area in the preservation of organic matter (OM) in a paralic sedimentary environment. The Squamish Delta is actively pro grading delta, located at the head of Howe Sound. Bulk TOC values across the Squamish Delta are low, ranging from 0.1-1.0 wt.%. The carbon/total nitrogen ratio (Corg/N) ranges from 6-17, which is attributed to changes in OM type and facies variations. The < 25 um fraction has TOC concentrations up to 2.0 wt.%, and a C o r g/N ratio that ranges from 14-16. The 53-106 um fraction has higher TOC concentrations and C o r g/N ratios relative to the 25-53 um fraction. The C o r g/N ratio ranges from 9-18 in the 53-106 um fraction and 5.5-10.5 in the 25-53 urn fraction. Surface area values for bulk sediments are low (0.5-3.0 m2/g) due to the large proportion of silt size material. Good correlation between surface area and TOC in bulk samples suggests that OM is adsorbed to mineral surfaces. Similar relationships between surface area and TOC were observed in size-fractionated samples. Mineralogy and elemental composition did not correlate with TOC concentration. Keywords: Squamish Delta; Organic Matter; Surface Area; Petroleum Source Rock Formation 7 2.2. Introduction: Only 1% of the OM found in the World's oceans will be incorporated into marine sediments and preserved (Suess, 1980). Eighty to ninety percent of OM is recycled within the photic zone, with only 10% of OM exported to the deep sea (Hedges and Keil, 1995). Of this 10%, approximately 90% is oxidized before it reaches the sea floor. As a result, an understanding of the mechanisms involved in the preservation of OM in sediments is very important, especially when considering petroleum source rock formation. A number of controlling factors for OM preservation have been put forward, including the bulk sedimentation rate, sediment source (terrestrial or marine), OM composition, redox conditions within the water column and sediments (Calvert et al, 1996), and sediment surface area (Mayer, 1994; Hedges and Keil, 1995). Sediment source determines the composition of OM and thus the susceptibility of the OM to remineralization. The bulk sedimentation rate controls the burial of OM in the sediments, with the ratio of inorganic to organic sediment particles influencing the potential dilution of OM as it is buried. The redox conditions within the water column affect both the rate, and how much OM is remineralized prior to arrival on the sea floor. Other physical oceanographic parameters such as water depth and temperature also indirectly affect OM preservation. Factors such as sedimentation rate, sediment source and water column redox conditions have the greatest influence on particulate organic matter (POM), which behaves as discrete particles in an aqueous system (Calvert et al, 1996). It has been argued (Mayer et al, 1993; Mayer, 1994) that organic material, which is less dense than mineral matter, is hydrodynamically equivalent to fine-grained inorganic particles, thus explaining why fine-grained sediments tend to have higher TOC concentrations. Mayer et al (1993) showed, however, that on average, less than 10% of TOC can be separated by density into a fraction with hydrodynamic equivalence to fine-grained minerals. This result implies that most (approx. 90%) of OM in fine grained-sediments is adsorbed to mineral surfaces, and that only a very small proportion of OM may be present in discrete particle form. The coupling of organic matter with mineral grains in marine sediments and soils is widely thought to be the determining factor affecting the preservation of organic matter 8 (Tiessen et al, 1984; Oades, 1988; Anderson, 1988; Mayer, 1993; Mayer, 1994), although the nature of the relationship is still not fully understood. The most widely accepted theory is that adsorption of OM onto mineral surfaces provides protection from enzymatic attack and subsequent remineralization of the OM (Mayer, 1994; Hedges and Keil, 1995). Recent work (Ransom, 1997; Mayer, 1999) suggests that OM is distributed in discrete patches over mineral surfaces, concentrating in areas of low relief such as cracks and fissures. Mayer (1994) showed that the majority of the surface area in continental sediments is contained in mesopores (2-50 nm) which are small enough to shield any adsorbed OM from hydrolytic enzyme attack Such a view is contrary to the belief that OM is bound to particle surfaces in the form of a monolayer that coats the entire grain surface (Hedges and Keil, 1995). However, it is possible that discrete distribution of OM on inorganic particles is still proportionally "monolayer equivalent". Mayer (1994, 1999) suggests that an organic loading of about 1 mgOC/m2 of inorganic substrate is the approximate concentration expected if average sized organic molecules were distributed evenly across all mineral surfaces. The link between sediment surface area and OM concentration occurs in both near- and offshore environments. An excellent correlation between surface area and TOC exists in continental margin sediments (Figure 1; Mayer, 1994, 1999; Hedges and Keil, 1995; Bergamaschi et al, 1996). Typical organic carbon (OC) loadings for continental margin sediments range from 0.5-1.0 mg OC/m (Mayer, 1994); however, under certain environmental conditions this range can be exceeded and 'super-monolayer' coverage can be attained (Hedges and Keil, 1995). Levels of 2.3 mgOC/m2 have been found in the organic-rich sediments on the Peru continental margin (Bergamaschi et al, 1996). Elevated carbon loadings, such as those observed on the Peru continaental margin, may be explained by prolific primary production (l-10g C/m /day), high bulk sediment TOC values (8.41 wt.%; Bergamaschi et al, 1996) and occasional water column anoxia (Mayer, 1994). In coastal sediments, the relationship between surface area and TOC is less distinct, perhaps due to the dynamic nature of paralic environments and the large input of macroscopic particulate OM. The overall result of adsorption of OM to mineral surfaces is that TOC concentration is proportional to surface area, and that highest concentrations of OM are found in areas of fine-grained sediments. 9 ^ £ § <o £ § o • 2 O N -•S ^ "5 s a g O <U u fc O <U o ^ s ^ c ^ =o <W — I I I ^ *J g e ^ P . a a a e S C 5 ^ I « ^ =x C <£, Si a P « < "S3 s •2 O 3 « a 2 s 53 .S s on || 3 O N O N 10 Deltas are common paralic environments that receive large quantities of allochthonous organic material. Allochthonous organic material is thought to be an important source of oil and gas in terrestrial and paralic environments (Combaz and de Matharel, 1978; Thomas, 1982); however, the significant dilution effect caused by a high input of inorganic material often causes low total organic carbon (TOC) concentrations. However, high sedimentation rates also serve to decrease the burial time of OM in sediments, thus quickly removing a given 'parcel' of sediment from the oxygen-rich surface sediment layer, where OM degradation is most rapid. The result is increased preservation potential of OM with increasing sedimentation rates (Johnson Ibach, 1982). The effects of high sedimentation rates and OM dilution can be seen in the Tertiary strata of the Niger Delta, where almost all TOC values are < 2 wt.% (Bustin 1988), and yet this region produces both oil and gas in commercially viable quantities. The Makaham Delta in Borneo also produces both oil and gas from well preserved deltaic sequences of Miocene to Holocene age (Combaz and de Matharel, 1978). The supply of OM to the Makaham Delta is entirely of terrestrial origin, as is the OM in the Miocene source rocks, confirmed through the analysis of various oil and source rock extracts (Combaz and de Matharel, 1978). Resistant organic debris such as pollen, spores, waxes and leaf cuticles represent only a minor portion of the kerogen present in the source rocks of the Mahakam Delta (Combaz and de Matharel, 1978). On the other hand, partially degraded, more recalcitrant terrestrial OM, similar to that commonly adsorbed to mineral surfaces (Mayer, 1994), forms the major kerogen fraction in the Miocene source rocks. Thus, good evidence exists to suggest that surface area plays an important role in preserving OM in deltaic sequences, and as a result is a factor in source rock formation in marine depositional environments. This study examines the effects of changes in sediment surface area on OM concentrations across the Squamish Delta, Howe Sound, BC, which is an excellent modern analogue for an ancient deltaic petroleum source rock-forming environment. 11 2.2.1. Study Area The main study area is located on the front of the Squamish Delta at the head of Howe Sound, in southwest British Columbia (Figure 2). Samples were also taken at a number of other locations along Howe Sound, and in the Strait of Georgia (Figure 2). Howe Sound is a complex glacial fjord consisting of deep basins (up to 285 m deep) separated by submarine glacial sills that rise to depths of 30 m in places (Syvitski and MacDonald, 1981). The Squamish Delta consists of an actively prograding prodelta, with proximal marsh land areas divided by the Squamish River distributaries. The central Squamish distributary is dormant, as water is diverted by a river-training dyke into the western distributary arm. 2.2.2. Sedimentology Howe Sound has two dominant sediment sources, the Squamish and Fraser rivers. The Squamish River supplies approximately 80% of the recent Howe Sound deposition, whilst the Fraser River, located approximately 15 km south of Howe Sound, accounts for the remainder (Syvitski et al, 1981). The tidal regime within Howe Sound is semi-diurnal, with the upper limit of tidal flux marked by the confluence of the Squamish and Mamquam Rivers, 5 km upstream of the Squamish Delta. The Squamish River generates the rapidly prograding Squamish Delta, which extends south of the river mouth to a distance of 3-5 km. There are also a number of small creeks along Howe Sound that supply sediments, producing small fan deltas. The Squamish River drains an area of approximately 3600 km2 that is characterized geologically by granitoid intrusions, volcanics and some metamorphic rocks. The average discharge of the Squamish River is 300 m3/s, rising to approximately 600 m3/s during the spring/summer freshet, and falling to approximately 100 m3/s in winter (Hickin, 1989). 12 123°2ff 123°lo' 49 4')' 25' H o w e S o u n d 49' ^ S Q U A M I S H ••'32 c-r D E L T A : $34 . Primary Study Ares 49' Sample Station 200 • -Bathymetry 174 Water Depth in Metres River/Lake Topographic Contours Nautical Miles West Vancouver 123°30' 123°10' 49° 49° 49° 49 Figure 2: Map of Howe Sound, British Columbia, showing the locations of the grab sample field (SD 1-25) on the Squamish Delta, and core samples (26-34, Cl, C2, C3, Woodfibre Pulp Mill and Port Mellon Pulp Mill). 13 Sediment grain size across the Squamish Delta is variable, ranging from medium grained sand to clay. Syvitski et al (1981) characterized the Squamish River outfall as muddy sand facies, that grades into predominantly sandy muds on the eastern shoreline and muds on the western shoreline. The principal control on deltaic sediment distribution is the western arm of the Squamish River, which has produced a subsurface channel marked by the presence of a sandy silt facies. Sediments outside this channel fine laterally to the east and west, from silty sand to silty mud and mud facies. 2.3. Methods: 2.3A. Sample Collection The Squamish Delta was sampled using a Shipek grab operated from the Canadian Coast Guard vessel CCGS Vector in July 1998. Twenty five surface grab samples were taken in a grid extending south from the mouth of the Squamish River to a distance of 4 km (Figure 2). Core samples were taken using a gravity corer in a number of locations along Howe Sound, using a combination of the CCGS Vector and a small 19 ft launch (Figure 2). Grab samples were placed into plastic sample bags and cores were kept in the core barrel (Cellulose Acetate Butyrate tubing). Grab samples and cores were stored frozen, and sub-sampled at a later date in the laboratory. 2.3.2. Sediment Size Fractionation Sediment size fractionation was carried out in order to observe changes in TOC, total nitrogen (TN), surface area and mineralogy/elemental composition within different grain sizes. Prior to fractionation, bulk sediment samples (approximately 10 g wet weight) were freeze dried for elemental and surface area analysis. Combinations of sieving and settling techniques based on Stokes Law (Krumbeim and Pettijohn, 1938) were used to separate samples into three primary size fractions: 53-106 pm, 25-53 pm and < 25 pm. The size fractions were chosen based on Wentworth's size classification. Stainless steel sieves were used to separate the coarser fractions (53-106 pm and 106-250 pm) via wet sieving using distilled water; fractions coarser than 250 pm were not analyzed in this project. 14 Fractions finer than 53 urn were suspended in distilled water, magnetically stirred, sonicated in a water bath (at approx. 5°C) for 15 minutes (Genrich and Bremner, 1973), and left for the appropriate Stokes settling time to sediment particles in the 25-53 um range. This method of disaggregation prior to settling has been shown by Grenrich and Bremner (1973) to have negligible effects on C and N content of sediments/soils. Bergamaschi et al (1996) showed that loses of TOC during rinsing with distilled water and subsequent fractionation resulted in overall loses of < 2% of the total organic carbon. The supernatant was decanted and centrifuged (3000 rpm) to isolate the < 25 um fraction, whilst the 25-53 um fraction was twice resuspended in distilled water and settled to ensure complete separation of the two finest fractions. Following fractionation, the split samples were frozen and freeze dried prior to chemical analysis. Selected samples taken from the < 25 um fraction were also separated using Stokes settling techniques in order to isolate the < 2 um fraction. 2.3.3. Elemental Analysis 2.3.3.1. Organic Carbon and Nitrogen Total carbon (TC) and nitrogen (wt.%) were determined on bulk and fractionated sediment samples using a Carlo Erba NA-1500 CFIN analyzer (Verardo et al, 1990). The standard error was +/- 1%. Macroscopic organic debris was removed prior to analysis under a binocular microscope. Total organic carbon (TOC) was determined by difference after the subtraction of inorganic carbon in carbonate form. 2.3.3.2. Inorganic Carbon The amount of carbon in carbonate form in each sample was determined using a coulometric titration technique on a CO2 coulometer (Coulometrics ® Incorporated, Model 5010). The standard error was +/-5%. 2.3.4. Major and Minor Elements X-ray fluorescence techniques using glass fusion beads (major elements) and pressed sediment pellets (minor elements) analyzed on a Philips ®PW 2400 were used as described by Calvert et al (1984, 1990). The standard error was +/- 3% for major elements (except sodium, +/- 10%) and +/- 5% for minor elements. 15 2.3.5. 8 1 3 C 8 1 3 C values were determined on acid-treated sub-samples, using a PRISM stable isotope mass spectrometer linked to a NA 1500 NC elemental analyzer (FISONS ClnCsample uC/lzCstd Instruments). Results are reported in the delta notation -1 xlO3 V J relative to the Pee Dee Belemnite standard. The standard error was +/- 0.05 /oo. 2.3.6. Surface Area Samples were first oxidized using a combination of hydrogen peroxide (30%) and sodium pyrophosphate (0.1A/) (Sequi and Aringhieri, 1976) in order to remove organic matter from the samples. This process was carried out in a water bath (70-80 °C) for 48-96 hrs; aliquots of H2O2 were added twice daily until oxidation was complete as marked by the cessation of CO2 evolution. Samples were then rinsed twice in distilled water to remove any residual inorganic salts and dried. Freeze drying, oven drying and oven drying under vacuum were tested as methods of sample drying prior to analysis; good agreement was found between all three methods. A Micromeritics ASAP 2010® surface area analyzer was used to determine surface area by N2 adsorption, using both single and multi point BET (Brunauer, Emmett, Teller) methods (Gregg and Sing, 1982; Mayer, 1993). Prior to analysis, samples were degassed at 350°C for a minimum of 6 hrs. The standard error of the method ranged from 2-4 %. 2.3.7. Mineralogy and Petrography Mineralogy was determined using standard X-ray diffraction techniques. Basic petrographic examination was done using a binocular microscope. More detailed examination of the finer fractions was carried out using a scanning electron microscope. This technique served to verify the presence/absence of particulate organic debris in different size fractions under magnifications up x 10,000. 16 2.4. Results: 2.4.1. Bulk Analysis Bulk sediment analysis (Table 1) indicates both good correlation between sediment surface area and TOC and TN, and between TOC, TN and C o r g/N and the hydrodynamics of the delta. 2.4.1.1. C and N Distributions 2.4.1.1.1. Bulk Sediments TOC concentration (Figure 3) across the delta front ranges from 0.1-1.0 wt.%, with the lowest concentrations localized in a subsurface channel that extends southwards from the western distributary of the Squamish River. This channel bifurcates approximately 2 km from the river mouth. The dominant facies found within this channel is medium to coarse sand, with varying amounts of silt and clay. The highest concentrations of macroscopic particulate organic debris occur in this region of the delta, suggesting hydrodynamic equivalence of POM with the coarse sediment in this area. The POM was identified by SEM as mainly wood fragments, wood fibers and various leaf fragments. The low TOC values that occur in this channel represent mainly adsorbed OM, as the macroscopic POM was removed prior to analysis. TOC concentration generally increases towards the peripheral areas of the delta where the flow velocity is lowest. In these areas, finer-grained sediments with greater proportions of fine silt and clay sized particles have settled under the low energy conditions. Total nitrogen concentrations range from 0.01-0.08 wt.% in the delta region; spatially, nitrogen shares a similar distribution to TOC, with low concentrations in the subsurface channel and higher concentrations in peripheral areas of the delta. The Corg/N ratio ranges from 6-16.5, which covers the accepted ranges of marine OM (6-9), degraded soil material (10-14) and terrestrial material (15-200). The lowest Corg/N values occur within the subsurface channel. Diatom frustules are found in these sediments (<0.1%) indicating the presence of marine OM; however, the C o r g/N values of 6-9 within the channel most likely result from lower TOC concentrations relative to TN concentrations and not from accumulation of marine organic matter. The change in TOC 17 Sample TOC T N C o r g / N SA # (wt%) (wt%) (m2/g) SD1 0.91 0.06 16.01 1.92 SD 2 0.70 0.04 15.88 1.84 SD 3 0.86 0.05 16.48 2.94 SD 4 0.78 0.05 15.71 1.73 SD 5 0.41 0.03 12.96 0.94 SD 6 0.14 0.02 8.37 0.62 SD 7 0.57 0.04 14.67 1.11 SD 8 0.61 0.04 14.21 1.96 SD 9 0.57 0.04 13.16 2.21 SD 10 0.85 0.05 15.90 1.52 SD 11 0.10 0.01 6.95 0.68 SD 12 0.66 0.04 15.88 1.40 SD 13 0.21 0.02 9.24 0.62 SD 14 0.79 0.06 14.29 2.35 SD 15 0.09 0.01 6.21 1.06 SD 16 0.60 0.04 13.49 1.67 SD 17 0.52 0.04 13.61 2.75 SD 18 0.86 0.06 13.83 2.10 SD 19 0.36 0.03 12.84 0.76 SD20 0.18 0.02 9.49 0.65 SD 21 0.69 0.05 13.84 1.95 SD 22 0.60 0.04 13.97 1.81 SD23 0.53 0.04 12.70 2.83 SD 24 0.53 0.04 14.61 1.19 SD 25 0.72 0.05 14.01 2.20 SD 26 0.80 0.06 13.45 SD 28 0.49 0.05 10.49 SD 30 0.71 0.06 12.74 N / A SD 32 0.86 0.06 13.90 SD 34 0.96 0.07 14.66 Woodfibre 1.71 0.08 21.58 Port Mellon 6.90 0.26 26.35 Cl 1.45 0.11 13.56 N / A C2 1.98 0.20 9.87 C3 1.66 0.15 10.79 N/A: Not Analyzed Table 1: TOC, TN, Cor/N and surface area (SA)for bulk surface sediment samples from the Squamish Delta, and from secondary core locations in Howe Sound. 18 0 c o C N , . A - - W A V V V A . W,W>V>m V V A W A V A > * V , ^ M V A W » W > V W A W A V A V . V . V . V A W . V A V A V A V A V A V A W A 1 kA^^AVAVAVAVAVAVAv* . T A V A V A V A W A W A L A V A V A V A V A V A V A V A V \ V A V A V A W A W A V A V A W " - ' W A V A V A V A V A W A ; . V A V A ' - V V . - • '•jTirTS-\ V > V » - m - » - K V A 3 V A W A W A W ^ A T V A V A V A V A W * A V A W - v . . . . . . . ^ V A V A V A A . . A V A V A V A W A V A V V A V A V A V A V A V A W ^ W A V * ' " 1 'J u M V A V V A V V A V 3 © o w rt O -E > c_ w ... G C **' 6 ^ i> g- 3 rt 2 £ c o 0 © CO © o © U O f— S3 a te sg P R d d d ci d CO O CN © a U i v. •Sf -5 2 -13 "a =: K 8 = Q • * § 1 -s: * "S3 2 a £ 1 C to § a, S . 5 4) 19 concentration relative to TN within the channel is a result of reduced surface adsorption, caused by the increase in grain size. This drop in TOC concentration is exclusive to the subsurface channel, and is not observed in peripheral areas of the delta, where TOC levels are higher. TN concentrations are constant across the whole delta. Most of Corg/N values lie in the range of degraded soil OM (10-14) (Muller, 1977). Nitrogen enrichment resulting from carbon depletion can result from direct remineralization of carbon by bacterially mediated breakdown in conjunction with preferential adsorption of nitrogen rich compounds onto mineral surfaces (Muller, 1977), or from high concentrations of inorganic nitrogen (NH4+) associated in clay minerals, such as illite, where it can exchange easily for K + in the interlayer sites (Muller, 1977). As a result, it is difficult to determine whether the OM that falls into the 10-14 range is: 1) terrestrial material partially degraded under marine conditions and/or (2) degraded terrestrial material originating from soils in the Squamish valley. The C o r g/N values above 15 suggest that some fresh terrestrial OM is reaching the delta via the Squamish River, or directly from the steep valley sides. Squamish Delta samples (SD 26 to 34) show an overall increase in TOC and Corg/N towards the Woodfibre pulp mill site (TOC = 1.7 wt.%, C o r g/N = 21.6; Figure 2). The high values at the Woodfibre mill are a result of high input of OM from effluent discharge together with spillage of saw dust and wood chips from transport barges that regularly service the mill. This is also the case for the Port Mellon pulp mill on the western shore of Howe Sound (Figure 2). Samples taken in the central and southern parts of Howe Sound (C1-C3) have TOC values of 1.4-2.0 wt.%, and low TN (<0.2 wt.%) concentrations. The C o r g/N values of 9-13 are indicative of increasing marine OM influence in the southern half of Howe Sound. 2.4.1.1.2. Size Fractionated Sediments There are clear trends and distribution patterns in TOC and TN in the size fractionated sediments (Figure 4, Table 2). 20 B [size Fraction (Micrometres)) Figure 4: Distribution of A) TOC and B) TN across the Squamish Delta for the <25 jUm, 25-53/Jm, 53-106/itm and 106-250jUm size fractions. 21 <25 25-53 # TOC (wt.%) TN (wt.%) Corg/N SA (m2/g) TOC (wt.%) TN (wt.%) Corg/N SA (m2/g) SD 1 0.98 0.07 15.05 3.54 0.24 0.03 9.32 0.82 SD 2 1.12 0.08 14.48 4.32 0.18 0.02 9.96 0.95 SD 3 0.84 0.06 14.89 5.35 0.20 0.03 7.68 1.10 SD 4 1.09 0.08 14.20 3.89 0.17 0.02 7.54 0.79 SD 5 1.69 0.11 14.82 5.90 0.19 0.02 8.86 0.89 SD 6 1.95 0.13 14.68 6.28 0.15 0.02 8.51 1.14 SD 7 1.28 0.08 15.32 5.88 1.38 0.20 7.02 0.77 SD 8 0.78 0.05 14.71 3.92 0.14 0.02 7.88 1.60 SD 9 0.76 0.05 14.72 6.31 0.13 0.02 7.39 1.29 SD 10 1.18 0.08 14.41 5.90 0.15 0.02 7.04 1.19 SD 11 1.65 0.11 14.64 5.78 0.19 0.02 9.83 1.02 SD 12 1.38 0.10 13.76 5.27 0.17 0.02 8.23 1.23 SD 13 1.63 0.11 14.45 7.04 0.12 0.02 7.16 1.09 SD 14 1.44 0.06 13.29 5.67 0.12 0.02 6.94 1.19 SD 15 1.52 0.11 13.72 6.90 0.17 0.02 9.98 0.94 SD 16 0.99 0.07 14.83 5.18 0.13 0.02 5.99 1.17 SD 17 0.81 0.06 13.69 4.63 0.11 0.02 6.52 1.05 SD 18 1.13 0.08 13.69 4.31 0.15 0.02 7.35 N/A SD 19 1.93 0.12 16.67 5.02 0.19 0.02 9.17 1.04 SD 20 1.46 0.18 17.94 7.81 0.22 0.02 12.52 1.35 SD21 1.41 0.06 14.17 5.88 0.11 0.02 4.65 1.14 SD 22 1.36 0.07 14.37 5.14 0.13 0.02 7.67 1.25 SD 23 1.02 0.06 13.90 5.44 0.11 0.00 N/A 0.25 SD24 1.16 0.08 14.44 5.24 0.13 0.02 6.48 1.10 SD 25 1.06 0.07 14.11 5.32 0.07 0.01 7.37 0.98 N/A : Not Available/Analyzed Sample 53-106 >106 # TOC (wt.%) TN (wt.%) C„rg/N SA (m2/g) TOC (wt.%) TN (wt.%) C„g/N SD 1 0.84 0.05 17.91 0.95 7.05 0.26 27.36 SD 2 0.31 0.03 12.26 0.79 2.62 0.11 24.84 SD 3 0.74 0.04 17.92 1.00 7.31 0.27 26.82 SD 4 0.39 0.03 14.75 0.80 1.71 0.08 22.52 SD 5 0.29 0.03 11.26 0.79 0.17 0.02 11.04 SD 6 0.18 0.02 8.81 0.59 0.04 0.00 N/A SD 7 0.33 0.03 13.24 0.90 0.74 0.04 17.12 SD 8 0.40 0.03 14.67 1.12 0.46 0.03 14.99 SD 9 0.43 0.03 15.32 1.11 0.91 0.04 20.71 SD 10 0.52 0.03 15.25 1.04 0.75 0.04 19.70 SD 11 0.12 0.01 8.95 0.76 0.06 0.01 5.07 SD 12 0.48 0.03 15.29 0.99 0.85 0.05 17.77 SD 13 0.14 0.02 6.96 0.81 0.02 0.00 N/A SD 14 0.60 0.04 14.79 1.15 3.27 0.14 23.20 SD 15 0.34 0.03 12.58 0.59 0.01 0.00 N/A SD 16 0.37 0.03 12.73 1.04 1.85 0.08 22.09 SD 17 0.45 0.03 14.80 0.97 0.99 0.06 17.43 SD 18 0.49 0.04 13.65 1.08 5.75 0.24 23.48 SD 19 0.30 0.02 16.72 0.78 0.27 0.03 9.36 SD 20 0.25 0.02 10.49 0.74 0.12 0.01 9.80 SD 21 0.67 0.04 16.19 1.01 0.48 0.03 14.29 SD 22 0.43 0.03 14.70 0.89 0.36 0.02 16.62 SD 23 0.41 0.03 15.24 1.25 1.15 0.06 19.19 SD 24 0.16 0.02 9.41 0.64 0.14 0.02 7.29 SD 25 0.54 0.04 14.64 1.09 2.21 0.09 23.31 N/A : Not Available/Analyzed Table 2: TOC, TN, Corg/N and surface area (SA)for the <25jUm, 25-53pm, 53-106pm and 106-250/Jm size fractions from the Squamish Delta. 22 The <25 um and 106-250 urn size fractions have the highest levels of TOC relative to the two intermediate fractions. The high TOC concentrations in the <25 um fraction are attributed to high sediment surface areas and adsorption of organic material to particle surfaces (Mayer, 1994; Bergamaschi et al, 1997). The high abundance of OM in the coarsest size fraction is attributed to the presence of macroscopic particulate organic debris as revealed by microscopic examination (visible macroscopic organic debris was removed from the samples by hand). The intermediate size fractions, 25-53 um and 53-106 um, have low OM concentrations when compared to the coarsest and finest fractions. The 53-106 um size fraction has slightly higher levels of OM than the 25-53 um fraction, possibly due to preferential adsorption in this fraction. The spatial distributions of TOC for the different size fractions are not as well defined as that of the bulk sample distribution. In the 106-250 um and 53-106 um fractions, the highest concentrations of TOC occur on the eastern side of the delta, where Gonzales, Shannon and Olesen Creeks supply particulate material. The 25-53 um fraction has no distinctive distribution pattern that correlates with facies distributions across the delta, which probably reflects low TOC (Figure 4). The < 25 um fraction has the highest concentrations of TOC across the central and western portions of the Delta (Figure 5), with values averaging 1.8-2.0 wt.%. On the eastern side of the delta, TOC levels are less than 0.8 wt.% for the < 25 um fraction which is attributed to the higher volumes of coarse sediments supplied by three creeks on the eastern margin of the delta. • * 2 There is a linear correlation (r = 0.9) between organic carbon and nitrogen for the < 25 um, 25-53 um and 53-106 um size fractions (Figure 6). Figure 6 also shows the data for the < 2 um fraction, which correlates well with the < 25 um, 25-52 um and 53-106 um fractions, having a similar, albeit slightly more nitrogen rich, C o r g/N ratio/OM composition. The 106-250 um fraction plots on a separate, more carbon rich regression (r = 0.99), which suggests that particulate organic detritus, with a higher C/N ratio, is concentrated the coarsest fraction, whilst the finer fractions are dominated by OM adsorbed to inorganic particle surfaces. Although the y-intercept is very close to zero, the 23 2 4 25 the small positive intercept value suggests a variable C o r g/N ratio due to the presence of a minor amount of inorganic nitrogen. 2.4.1.2. Surface Area Trends 2.4.1.2.1. Bulk Sediments A moderately significant positive correlation exists (r2 = 0.5) between TOC and sediment surface area in the bulk samples taken from the Squamish Delta (Figure 7a). This correlation between TOC and surface area for the bulk sediments (r2 = 0.5) is not as strong as is often observed (Mayer, 1994; Bergamaschi, 1997), suggesting that organic matter in Squamish Delta sediments may be present in forms other than that bound to particle surfaces. Several samples have significantly lower than predicted TOC concentrations from their surface areas (Figure 7a) and the correlation between TOC and sediment surface area is significantly improved (r2 = 0.69) when the low TOC/high surface area outliers are removed from Figure 7a (Figure 7b). A regression coefficient of r2 = 0.69 (Figure 7b) may indicate that OM is adsorbed to inorganic particle surfaces. The low TOC/high surface area outliers may be artifacts created during sample preparation and analysis. 2.4.1.2.2. Size Fractionated Sediments Size fractionated samples show highly variable relationships between TOC and surface area (Figure 8a). The < 2 pm fraction falls above the expected area on the regression line, which predicts that for surface areas of 20-25 m /g, TOC levels should be approximately 3.5- 4.5 wt.% (average TOC for < 2 pm = 2 wt.%). The 25-53 pm size fraction does not fall between the <25 and 53-106 pm fractions as expected, but rather shows a much smaller increase in TOC content with increasing surface area. The correlation of TOC with surface area (r2 = 0.55; Figure 8a), indicates that approximately 55% of the organic matter is bound to the surfaces of sediment particles. If Figure 8a is re-plotted (Figure 8b) without the data for < 2 pm fraction, the r2 value 26 U) E < 3.50 3.00 2.50 2.00 1.50 1.00 0.50 0.00 y = 1 .9902X + 0.531 r2 = 0.4928 0.00 • • • 0.20 0.40 0.60 0.80 1.00 TOC (wt.%) • TOC vs. SA Linear (TOC vs. SA) < c/> B 3.50 3.00 2.50 2.00 1.50 1.00 0.50 0.00 y = 2.0468x + 0.393 r2 = 0.6848 0.00 0.20 0.40 0.60 0.80 TOC (wt.%) • TOC vs. SA Linear (TOC vs. SA) 1.00 Figure 7: A) TOC vs. surface area for bulk sediment samples taken from across the Squamish Delta (n - 25); B) TOC vs. surface area for bulk sediment samples taken from across the Squamish Delta. Selected samples only (n = 23). 2 7 25.00 A B y = 6.4968x - 0.8156 r 2 = 0.55 _,OD C J I K * * ? 5 * * * * X X X T O C (wt.%) I X<2 • < 25 A25-53 X53-106 Linear regression: <2, <25, 25-53, 53-106 Y=3.6075x + 0.2005 r 2 = 0.75 * x x x X | T O C (wt.%)] • < 25 A25-53 X53-106 Linear regression : <25, 25-53, 53-106 Figure 8: A) TOC vs. surface area for size fractionated sediments from the Squamish Delta; B) TOC vs. surface area for size fractionated sediments from the Squamish Delta. The < 2jUm fraction has been omitted. 2 8 _increases to 0.75, suggesting that approximately 75% of OM may in fact be surface bound. The low overall concentrations of TOC found in the Squamish sediments may account for the lower than expected OC loadings for the finest fraction. Figure 8a suggests that approximately 30-50% more OM could be adsorbed at surface areas of 20-25 m2/g. The relationship between TOC and surface area in the Squamish Delta is not as strong as that found in sediments from continental shelf regions (Mayer, 1994; Hedges and Keil, 1995; Bergamaschi et al, 1997), where almost all organic matter is adsorbed onto inorganic substrates and little or no POM is present. However, the organic carbon loading for the Squamish sediments is approximately 2 mgOC/m2, which is higher than the typical range of 0.5-1.0 mgOC/m2 for marine sediments (Mayer, 1994), but similar to the loading of 2.3 mgOC/m found in the organic-rich Peru Margin sediments (Beramaschi et al, 1996). As a result of the variability in OC and surface area between samples, OC loadings are not consistent throughout the data set (Figure 8a,b), but it is clear that a break occurs in the data set between sediments less than, and greater than 25 pm (Figure 8). 2.4.1.3. 81 3C 1 "3 The 8 C (Table 3) data confirms the strong terrestrial OM signature suggested by the Corg/N ratio values across the delta (Table 1). Samples SD 1, 10, 19 and 25 represent a proximal to distal transect across the Squamish Delta. There is no distinctive change between the isotopic values of the bulk samples or their respective size fractions, which indicates that there is no fractionation of different types of OM spatially or between grain sizes. The values do confirm the distinctive terrestrial nature of the OM and minor marine OM input to the sediments. The sample taken near the Woodfibre Mill shows a similar isotopic composition to those taken on the Squamish Delta. Samples C1-C3 show a trend towards heavier carbon isotope ratios with increasing proximity to the Georgia Strait at the head of Howe Sound, which confirms increasing marine OM input to sediments in the southern part of the Sound. 29 Sample # Bulk Size Fraction (Micrometres) <25 25-53 53-106 SD1 -25.49 -25.53 -25.63 -26.26 SD10 -25.9 -25.77 -25.28 -26.11 SD19 -26.16 -26.43 -26.03 -26.02 SD25 -26.17 -25.76 -25.62 -26.25 Woodfibre -25.43 Cl C2 -24.36 -22.94 N/A C3 -23.42 N/A : Not Fractionated/Analyzed Table 3: S3C data for selected bulk and size fractionated (/Jm) samples from the Squamish Delta and secondary core locations in Howe Sound. 30 2.4.1.4. Mineralogy and Elemental Geochemistry 2.4.1.4.1. Mineralogy For the majority of samples analyzed, mineralogy is constant between samples and different size fractions, suggesting that mineralogy is not a significant control on OM distribution for these grain sizes. Minor variations occur in the relative abundance of iron-bearing oxide minerals. Quartz, plagioclase feldspar, phlogopite, chlorite, biotite, illite and amphiboles are indicative of an acid to intermediate plutonic igneous provenance. Minor differences occur in the relative amounts of these minerals between samples and between size fractions, but they are not sufficiently different to suggest preferential adsorption of OM to certain suites of mineral grains. This conclusion is supported by Thimsen et al (1998) and Keil et al (1998) who demonstrate that substrate mineralogy and geochemistry do not significantly affect OM adsorption onto particle surfaces in bulk or size fractionated sediments. 2.4.1.4.2. Elemental Geochemistry Major and minor element concentrations are constant between samples and between size fractions, suggesting a direct link with mineralogical composition. Elemental distributions can be linked to facies distribution across the delta front. Major and minor elements such as Si, Ti, Fe, Mg, K, Co, Cu, Ni, Sr, Rb and Y are controlled spatially by the subsurface channel on the western side of the delta. Other elements such as Al, Ca, As, Ba, Br and I show greater correlation with peripheral mountain streams that drain onto the eastern side of the delta. The highest concentrations of Si02 (65 wt.%) are exclusive to the subsurface channel where flow velocity is high, reflecting the preferential accumulation of coarse-grained quartz. Si02 also shows high concentrations in the coarser size fractions, although the difference between the < 25 pm and 53-106 pm fractions is on average < 3 wt.%. Ti02, Fe203, AI2O3, MgO, K 2 O , Mn304 and P2O5 share similar distributions, with highest concentrations occurring in peripheral delta areas, and lowest concentrations 31 found within the subsurface channel. AI2O3 is found at high concentrations outside the subsurface channel (up to 17 wt.%), reflecting the higher concentrations of phyllosilicate minerals that settle out in the low flow velocity areas of the delta. AI2O3, Fe2C>3, K 2 O and MgO all show highest concentrations in the < 25 pm fraction, which confirms the affiliation of these elements with fine-grained phyllosilicate minerals. The majority of the minor elements including Co, Pb, Ni, As, Zn, Y, Zr and Cu, show significant depletion within the coarse-grained channel facies, suggesting that they are also associated with the mica and clay minerals as is observed in the major element phases. Strontium (up to 700 ppm) and Cr (up to 140 ppm) show highest concentrations within the subsurface channel, suggesting hydrodynamic equivalence with large grain sizes. Bromine, Ba and Mn show no similarities with other element distribution patterns, and do not appear to show any kind of hydrodynamic equivalence with coarse- or fine-grained minerals. All the minor elements with the exception of Sr and Zr show highest concentrations in the < 25 pm fraction. Sr is concentrated in both the 25-53 pm and 53-106 pm fractions, with highest concentrations usually occurring in the intermediate fraction. Zirconium shows significant fractionation in the intermediate fraction (25-53 pm) suggesting that the mineral zircon is hydrodynamically concentrated in the 25-53 pm fraction. 2.5. Discussion: 2.5.1. Organic Matter Distribution The Squamish Delta receives a large supply of fresh, terrestrially-derived particulate OM in combination with degraded soil material. The influence of open water circulation in Howe Sound is minimal, and estuarine type circulation is not sufficient to supply the delta area with marine OM in significant quantities to dilute terrestrial biomarkers such as C o r g/N or 513C. The dominant source of the OM and sediments is the western distributary arm of the Squamish River (Figure 3), whilst other local sources include creeks on the eastern shoreline and the Woodfibre pulp mill to the southwest. The subsurface channel on the western side of the delta produces a depositional division between POM and adsorbed OM. This division is marked by a clear change in 32 sedimentary facies. Similar types of OM segregation have been observed in the Mahakam Delta (Combaz and De Matharel, 1978) and the Orinoco Delta (Nwachukwu and Barker, 1985), suggesting that subsurface currents are an important mechanism for concentrating particulate OM. Low energy areas of deltas, characterized by fine-grained sediments, serve to concentrate OM that is adsorbed to particle surfaces. Size fractionation of the Squamish sediments demonstrated a change in particulate to adsorbed OM for progressively finer grain sizes. Unlike the bulk sediment distribution of TOC (Figure 3), subsurface currents showed less control over the distribution of TOC in the different fractions, especially in the intermediate fractions where TOC concentration is relatively constant across the delta. The reasons for this are not entirely clear, especially as the mass distribution of the sediments across the delta shows that silt grade material is present in significant proportions across the delta. 2.5.2. Surface Area: A Mechanism for Petroleum Source Rock Formation? The correlation between TOC and surface area for bulk sediments across the Squamish Delta confirms that the two parameters are related (approximate r2 = 0.5; Figure 7a). The variability in this relationship, however, suggests within deltaic settings, and perhaps all paralic environments, that sediment surface area cannot be relied upon as a tool for accurately predicting TOC concentrations. Similar conclusions can be made about nitrogen concentrations, whose distribution and concentration closely match that of organic carbon. The relationship between TOC and surface area for size fractionated samples (Figure 8a,b) exhibits similar variations to those seen in the bulk sediment samples. For high surface areas, TOC values fall below predicted values (Figure 8a). Low bulk TOC concentration, and low overall TOC supply, in the Squamish sediments is the probable explanation. Alternatively, it is possible that terrestrial OM is not as readily adsorbed onto mineral surfaces when compared to marine OM. This hypothesis would account for the higher OM loadings that are often found in continental margin settings (Bergamaschi et al, 1997), which receive higher quantities of marine OM, and for a greater variability between TOC and surface area found in paralic environments (Mayer, 1994). 33 The variability in the TOC/surface area relationship at lower surface areas may in part derived from the presence of particulate organic matter in the samples. However, the relationship between carbon and nitrogen (Figure 6) strongly suggests that only the 106-250 pm fraction contains particulate material because of its higher carbon/nitrogen ratio. However, this does not preclude the possibility that no OM exists in this fraction that is bound to mineral surfaces. Work by Mayer (1993, 1994) also confirms that very little organic material can be density separated into fractions with hydrodynamic equivalence to fine-grained sediments, suggesting that OM in fine fractions is adsorbed and not in particulate form. It is likely that rapid sedimentation rates and rapid burial of organic matter serve to augment the adsorption process. Quick removal of mineral surface-bound OM from the water column and the oxygen rich surface sediment layer allows adsorbed OM to remain on particle surfaces and reduces the chance for remineralization, resulting in a higher preservation rate. In addition, OM that is not adsorbed to particle surfaces before it reaches the sediments will be quickly buried, which increases the potential for OM to become adsorbed to mineral surfaces, 'in situ'. The ultimate fate of particulate OM in sediments depends on the chemical conditions of the overlying water column and the sediments, the sedimentation rate and the overall resistance of the OM to enzymatic attack. Spores, pollen grains and certain plant components such as leaf cuticles are very resistant to degradation and thus represent the major components of terrestrially-derived palynological suites found in sedimentary rocks. It is likely that the remainder of the particulate material, which for the Squamish Delta is mainly woody material, will be broken down into amorphous humic or sapropelic material, that will either be further broken down into humic/fulvic acids or possibly bound to available inorganic particle surfaces within the sediments. Mayer (1993, 1994) confirmed that POM is not present in significant quantities in fine-grained sediments, and that levels of POM cannot explain TOC concentrations found in fine-grained continental margin sediments. Thus high surface areas typical of offshore sediments represent the 'major repository' for OM in marine sediments. It is unlikely, then, that POM is a significant contributor to hydrocarbon source rock potential when 34 compared to the organic material that is preserved on mineral surfaces i.e. 'bound or adsorbed' organic matter. 2.5.3. Implications for Petroleum Geology The organic/inorganic relationships observed in the Squamish Delta make it a good, small scale, modem analogue for the environment of formation of deltaic petroleum source rocks in the geological rock record. OM from paralic environments such as deltas is usually type III OM, whose evolution pathway tends to produce gas rich source rocks with low oil producing potential. However, under certain catagenic conditions, such as those seen in the rocks of the Mahakam Delta (Combaz and De Matharel, 1978), economically significant quantities of oil can be produced when source rocks evolve via the type III pathway. The type II evolution pathway leads to oil-rich source rocks and, as found in the Niger Delta (Bustin, 1988), source rocks in paralic environments can evolve via the type II pathway. OM/surface area relationships observed in the Squamish sediments indicate that preservation of OM occurs in fine-grained sediment facies. The high sedimentation rates found in deltaic environments, coupled with shallow water depths, allow for the fast removal of particles with surface bound OM, which increases the preservation potential of OM, even under well oxygenated conditions. Overall, the lower levels of OC observed in the delta compared to sediments located in offshore, continental shelf settings, is most likely explained by dilution of OM with inorganic particles; however, OM accumulation becomes significant despite the dilution effect due to rapid sedimentation rates and large sediment volumes. The ability to preserve OM via adsorption is significant enough to produce petroleum source rocks, especially when considered on larger scales such as in the Niger Delta (Bustin, 1988), where subsidence and burial leads to maturation of source rocks. 35 2.6. Summary and Conclusions: The Squamish Delta is a typical paralic sedimentary environment, which receives organic matter primarily from the Squamish River and from other minor sources such as local creeks and the Woodfibre pulp mill. The supply of both inorganic and organic sediment components is affected by seasonal variations in rainfall, runoff and snowmelt, all of which influence the sediment transport capacity of the Squamish River. The organic matter is delivered in macroscopic particulate form, identified by SEM as wood fragments, leaf structures and large aggregates of wood fibers, and in cryptoscopic form that is bound to mineral surfaces. Partitioning of OM occurs between size fractions, producing a change from particulate/macroscopic to adsorbed organic material for progressively finer grain sizes. Distinctive compositional variations in the organic matter also occur in different size fractions, as demonstrated by changes in the C o r g/N ratio. Deltaic hydrodynamics and subsurface delta morphology affect the distribution of organic matter in bulk sediments, along with facies distribution and grain size. TOC levels are lowest in a subsurface channel that represents a continuation of the western distributary arm of the Squamish River. In this channel, current speed is high, and the largest amounts of coarse sediment and particulate organic debris occur. Peripheral areas where current speeds are lower are marked by an increase in TOC, supporting the hypothesis that TOC concentration is highest in areas of finer sediments due to their higher surface areas. Spatial distributions of TOC in size-ffactionated samples show less correlation with facies/grain size. TOC in the coarsest fraction is particulate, and has a distribution related to source proximity and hydrodynamic energy levels. The highest concentrations of TOC in finer fractions are found in areas of fine-grained sediments, which have high surface areas, and unlike coarser fractions are not specifically related to source proximity. A good relationship between TOC and sediment surface area exists in the Squamish sediments (average OC loading = 2 mgOC/m2), although it is not as well defined as that found in offshore, continental margin sediments (Mayer, 1994). The variability in this relationship is typical of a dynamic sedimentary environment, such as a delta, which receives large quantities of organic and inorganic material of various sizes, 36 and whose sediment supply is largely controlled by the seasonal variations in the Squamish River discharge. The greatest proportion of surface bound OM resides in the < 25 um fraction. However, fractionation of the < 2 urn fraction does not produce the expected TOC concentrations suggested by Figure 8a. The average TOC contents for the < 25 um and < 2 urn fractions (1.3 wt.% (n = 25) vs. 1.8 wt.% (n = 6) respectively) confirm that the majority of TOC is located in the clay fraction. The difference between observed and expected TOC concentrations in the fine fractions (Figure 8a) is likely the result of low overall TOC concentration in the bulk sediment. In a paralic environment such as a delta, TOC concentration is lower than expected, because overall TOC supply is low. Thus, the full adsorption capacity of mineral surfaces with respect to OM is not achieved, and TOC concentrations fall below expected levels (Figure 8a). The intermediate fractions are also characterized by low TOC concentrations, but these have relatively low surface areas. The lack of variation in substrate mineralogy/geochemistry and in the differences in the abundance of minerals between samples and between size fractions, suggests that adsorption of OM to particle surfaces is not significantly affected by the type of substrate. The hydrodynamics of a delta can be considered as an important mechanism that serves to segregate not only different sediment facies across the delta, but also different OM types, producing a system where high concentrations of recalcitrant OM can be found adsorbed to particle surfaces in certain areas. The presence of coarse and fine grained facies, and channel structures, as seen in the Squamish Delta, is similar to more complex sedimentary structures found in larger delta systems. This can lead to the co-occurrence of source and reservoir rocks, ideal for petroleum production. 37 2.7. Acknowledgments: Financial support for this research came from an NSERC grant to R.M. Bustin. We thank Steve Calvert for his advice on geochemical issues, and also Maureen Soon for her help with the various analyses. 38 2.8. References: • Anderson, D. W. (1988): The effect of parent material and soil development on nutrient cycling in temperate ecosystems. Biogeochem., Vol. 5, pp. 71-97. • Bergamaschi, B.A., Tsamakis, E., Keil, R.G., Eglinton, T.I., Montlucon, D.B., Hedges, J.I. (1997): The effect of grain size and surface area on organic matter, lignin and carbohydrate concentration, and molecular compositions in Peru Margin sediments. Geochimica et Cosmochimica Acta, Vol. 61, No. 6, pp. 1247-1260. • Bustin, R.M. (1988): Sedimentology and Characteristics of Dispersed Organic Matter in Tertiary Niger Delta: Origin of Source Rocks in a Deltaic Environment. The American Association of Petroleum Geologists Bulletin Vol. 72, No. 3, pp. 277-298. • Calvert, S.E., Cousens, B.L., Soon, M.Y.S. 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(1988): The retention of organic matter in soils. Biogeochem., Vol. 5, pp. 35-70. Ransom, B., Bennett, R.J., Baerwald, R., Shea, K. (1997): TEM study of in situ organic matter on continental shelf margins: occurrence and the "monolayer" hypothesis. Mar. Geol. Vol. 138, pp. 1-9. 40 Sequi, P., Aringhieri, R. (1977): Destruction of organic matter by Hydrogen Peroxide in the presence of Pyrophosphate and its effect on soil specific surface area. SOIL SCI. SOC AM. J., Vol. 41, pp. 340-342. Suess, E. (1980): Particulate organic carbon flux in the oceans - surface productivity and oxygen utilization. Nature, Vol. 288, pp. 260-263. Syvitski, J.P.M., MacDonald, R.D. (1982): Sediment character and provenance in a complex fjord; Howe Sound, British Columbia. CAN. J. EARTH. SCI. Vol. 19, pp. 1025-1044. Thimsen, C.A., Keil, R.G. (1998): Potential interactions between sedimentary dissolved organic matter and mineral surfaces. Marine Chemistry, Vol. 62, pp. 65-76. Tiessen, H , Stewart, J.W., Hunt, H.W. (1984): Concepts of soil organic matter transformations in relation to organo-mineral particle size fractions. Plant and Soil, Vol. 76, pp. 287-295. Tissot, B., Durand, B., Espitalie, J., Combaz, A. (1974): Influence of nature and diagenesis of organic matter in formation of petroleum. The American Association of Petroleum Geologists Bulletin, V. 58, No. 3, pp.499-506. Van Krevelen, D. W. (1961): Coal. Amsterdam, Elsevier publ. Co. Verardo, D.J., Froelich, P.N., Mclntyre, A. (1990): Determination of organic carbon and nitrogen in marine sediments using the Carlo Erba NA-1500 Analyzer. Deep-Sea Research, Vol. 37, No. 1, pp. 157-165. 41 C H A P T E R 3: THE ENVIRONMENTAL SIGNIFICANCE OF SEDIMENT SURFACE AREA ASA CONTROLLING FACTOR IN THE PRESERVATION OF POLYCHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS (PCDD/PCDF) IN SEDIMENTS ADJACENT TO WOODFIBRE PULP MILL, HOWE SOUND, BRITISH COLUMBIA. 3.1. Abstract: A sediment core was retrieved from an area adjacent to the Woodfibre Pulp and Paper Mill in Howe Sound, British Columbia, in order to examine accumulation, partitioning, residence time and surface area related preservation of total organic matter (TOC), dioxins (PCDDs) and furans (PCDFs). Downcore distribution of TOC (0.5-1.7 wt.%) in the bulk samples is relatively uniform, showing moderate correlation with surface area (rz = 0.4). Bulk PCDD/F concentration shows selective enrichment and depletion at specific sediment horizons, and a low to moderate correlation with surface area (f = 0.23-0.54). TOC in size fractionated sediments ranges from 0.3-11 wt.% and shows reasonable correlation with surface area (r2 = 0.51). The relationship between PCDD/Fs and surface area is congener specific, ranging from no significant correlation (TCDD vs. surface area; r = 0.05), to excellent correlation (HxCDF vs. surface area; r = 0.99). Results indicate that both dioxin and furan concentrations are related to sediment surface area. The relationship improves with increasing sediment depth and molecular chlorination, suggesting that sediment surface area affects both the residence time of industrial pollutants, and their overall preservation potential. Keywords: Woodfibre Pulp Mill; Organic Matter; Dioxins; Furans; Surface Area; Preservation 42 3.2. Introduction: Polychlorinated Dibenzo-p-dioxins (PCDDs) and Dibenzofurans (PCDFs) are a serious threat to the environment due to their ubiquitous nature, toxicity and strong resistance to biodegradation (Dannenberger et al, 1997). It is known that these compounds have a strong affinity for sediment particles (Tyler et al, 1994), making coastal sediments an ideal repository. PCDD/Fs occur in the sediments of most industrialized waterways in the United States and Europe (Evers, 1988,1989; Norwood, 1989) . The relationship between inorganic particle surface area and organic matter concentration has already been established in uncontaminated sediments (Mayer, 1993, 1994, 1999; Hedges and Keil 1995), hence it was considered probable that surface area adsorption may be responsible for the preservation and distribution of organochlorine compounds in marine sediments. There are 75 PCDD congeners and 135 PCDF congeners, each with a different arrangement/quantity of chlorine atoms in the chemical structure. 2,3,7,8-terachlorodibenzo-p-dioxin (2378-TCDD) has received wide attention due to its carcinogenic nature, and has been shown to kill 50% of laboratory guinea pigs when administered at a dosage of 0.6 pg/kg of body mass (Sparschu et al, 1971), although such high fatality rates are not observed in all species. Data show that the toxicity of individual congeners is related to the positioning of chlorine atoms in the chemical structure, and that congeners with chlorine atoms at the 2,3,7 and 8 positions are the most toxic (Hites, 1990) . PCDD/F toxicity in marine and fresh water sediments is measured against guidelines set out by the Canadian Council of Ministries of the Environment. Values for PCDD/F of 0.85 ng/kg TEQ (Toxic Equivalency; ISQG - Interim Sediment Quality Guidelines) and 21.5 ng/kg TEQ (PEL - Proabable Effect Level) were chosen, based upon the degree of adverse biological effects resulting from exposure to contaminated sediments. TEQ is calculated by multiplying the measured sediment concentration in ng/kg by a TEF value (Toxic Equivalency Factor); 2,3,7,8-TCDD is known to be the most toxic and, therefore, has a TEF of 1.0. Since the more chlorine atoms present in the molecular structure, the lower the TEF value, OCDD has a TEF of 0.0001. 43 Sources of PCDD/Fs in the environment are numerous, although they usually originate as unwanted trace contaminants in industrial processes, and not from direct manufacture (Fielder, 1996). Atmospheric sources include combustion of wood and waste from incinerator plants (Fielder, 1993, 1996), and coal fired power stations (Riggs, 1995). Effluent wastes from industrial processes, most notably from solid waste incineration (Domingo et al, 1999) and from the pulp and paper industry, also contain PCDDs and PCDFs. Chlorinated pesticides, dry cleaning distillation residues, automobile exhaust emission and combustion of landfill gases are also known sources of PCDD/Fs (Fielder, 1996). There are a number of distinct sources of PCDD/Fs, which contribute to the total contamination from pulp and paper mills. Prior to 1992, wood chips treated with tetra-and pentachlorinated phenols to prevent fungal growth were supplied to pulp mills (Luthe, 1996). The tetra- and pentachlorinated phenols were subsequently transformed into PCDD/Fs during the bleaching process and then carried through into mill effluent. The use of polychlorinated phenol treated chips was banned in Canada by the Canadian Environmental Protection Act (CEPA) in 1992 (Luthe et al, 1995; Luthe, 1996). The bleaching process is the main source of PCDD/Fs in pulp mills, although since the ban on the use of elemental chlorine during bleaching by the CEPA, levels have fallen sharply. Also banned under the CEPA was the use of defoamers, which contained PCCD/F precursor chemicals. The strong chemical resistance of PCDD/Fs to biodegradation and their relatively low solubility in water (PCCD/Fs 10"6-10"12 mol/L, Doucette et al 1988; Ruelle et al 1997) means that both chemical families have long residence times in the marine environment, and the potential to accumulate in sediments. The organochlorine record in sediments from around the world is well documented in the literature (Huntley et al, 1998; MacDonald et al, 1992, 1998; Pearson et al, 1998; Rose et al, 1997; Sanders et al, 1992; Smith et al, 1990), and generally exhibits a steady increase since the 'industrial revolution' (approx. 1880-1910), rising to a maximum in the 1950's and 1960's when unchecked industrial emissions reached a peak. The most likely pathway by which these organochlorine chemicals reach the sediments is via adsorption onto inorganic particles, or in association with detrital organic matter, which can also have high surface area. As a 44 result, grain size and total organic carbon (TOC) concentration, which are strongly related, are anticipated to correlate with PCDD/F concentrations. As with TOC, highest concentrations of PCDD/Fs should be found in fine silt and clay sized sediment fractions, where surface areas are large (« 15-40 m2/g). Previous studies have also shown coarse-grained sediments to have high TOC concentrations (Adams and Bustin, 2001). However, TOC in coarse silt and sand sized sediment fractions is considered to be independent of surface area, because it is mainly found as discrete macroscopic particles. Adsorption of PCDD/Fs may occur in the effluent itself, which can have a high inorganic content and often contains fine-grained particulate material that does not settle out in sludge ponds. Adsorption may also occur after effluent discharge in the receiving waters, or in the sediments themselves. 3.2.1. Project Synopsis The aim of this project is to examine the partitioning of PCDD/Fs in sediments adjacent to the Woodfibre Pulp and Paper Mill, in a core retrieved from an area exposed to effluent discharge by the mill. The relationship between grain size and TOC, PCDD/F concentrations are assessed to ascertain if sediment surface area is a significant, contributing factor in the preservation of organochlorine compounds in marine sediments. 3.3. Methods: 3.3.1. Sampling A sediment core was taken using a Kasten box corer (gravity corer), adjacent to the Woodfibre Pulp and Paper Mill (Figure 9) on August 23rd 1999, from the Canadian Coast Guard vessel CCGS Vector. The core was subsampled on deck at 1 cm intervals to a depth of 10 cm and 2 cm thereafter (core length, 52 cm). Samples were frozen onboard in precleaned glass jars with Teflon lined lids (6 hr soak in Extran 300 ™, triple rinsed in distilled water, baked overnight at 300°C). Samples were kept frozen until subsampling. 45 Figure 9: Map showing the location of the sample site in Howe Sound, British Columbia, Canada. 46 3.3.2. Sediment Fractionation Selected samples were chosen, based on highest bulk PCDD/PCDF concentration, for size fractionation (Core intervals: 14-16 cm, 20-22 cm, 34-36 cm and 46-48 cm). Three other sediment intervals, of similar depth to those used for organochlorine analysis, were separated using wet sieving techniques (Krumbein and Pettijohn, 1938) in order to examine down core mass distribution, and to choose suitable size fractions that contained a mass sufficient for all the analyses. Samples were sieved at 63 um, and the remainder was analyzed using a Micromeritics®Sedigraph 5100. The results were combined to produce mass profiles for the four samples (Figure 10); the following size fractions for organochlorine analysis were chosen: < 2 urn, 2-10 urn, 10-20 um, 20-63 um and > 63 um. Sample separations were carried out in the regional dioxin laboratory at the Institute of Ocean Sciences (IOS), Sidney, B.C. in order to reduce any potential sample contamination prior to organochlorine analysis. Fractionation was carried out using a combination of wet sieving and settling techniques based on Stokes law (Krumbein and Pettijohn, 1938). The sieve and spatulas used were all stainless steal, and were triple solvent rinsed (Acetone x3, Toluene x3, Hexane x3) and baked at 150°C for 1 hr between samples. All glassware used during the settling procedure was washed, triple solvent rinsed, baked overnight at 350°C, and triple solvent rinsed again and dried inside a fume hood. All equipment used was covered/sealed in hexane rinsed aluminium foil immediately after cleaning. Narrow bore, flexible Teflon tubing (I.D. 2 mm), in conjunction with a disposable Pasteur pipette connected via rubber tubing to a water aspirator, was used to siphon off different size fractions during settling. The coarsest fraction, > 63 um, was sieved off, and the remaining solids, suspended in distilled water, were transferred to 2 L glass beakers for settling. Once separated, sediment size fractions were stored in 250 ml solvent rinsed glass jars with Teflon lined lids, and frozen prior to analysis. To remove particles from suspension in the < 2 um fraction, the water was centrifuged at 3500 rpm using a Beckman 64R centrifuge. Four, 1 L polycarbonate 47 48 centrifuge bottles were adapted by removing the neck of the bottle, so that they could be lined with hexane rinsed aluminum foil to prevent contamination (the polycarbonate centrifuge bottles could not be solvent cleaned in the same manner as glassware). Any leakage through the foil was discarded. The water was then stored in solvent rinsed 4 L bottles and stored in the fridge at 4°C, pending future analysis. 3.3.3. Elemental Analysis 3.3.3.1. Organic Carbon and Nitrogen Total carbon (TC) and nitrogen (TN; wt.%) of bulk and fractionated sediment samples was determined using a Carlo Erba NA-1500 CHN analyzer (Verardo et al, 1990). The standard error was +/- 1%. Macroscopic organic debris was removed prior to analysis under a binocular microscope. TOC was determined by difference after the subtraction of inorganic carbon in carbonate form. 3.3.3.2. Inorganic Carbon The amount of carbon in carbonate form in each sample was determined using a coulometric titration technique on a C O 2 coulometer (Coulometrics Incorparated, Model 5010). The standard error was +/- 5%. 3.3.4. Organochlorine Analysis 3.3.4.1. Sample Extraction, Cleanup and Fractionation Bulk and size fractionated sediment samples were homogenized unfrozen and 2 g aliquots were removed for moisture determinations. Analytical samples, approximately 10 g wet weight (w.w.), were dried with 125 g Na2S04 in a mortar and transferred into the glass thimble of the Soxhlet where they were spiked with a mixture of 13Ci2-labeled PCDD/Fs, a surrogate internal standard supplied by Cambridge Isotope Laboratories 49 (Andover, MA). The composition of the surrogate internal standard mixture and the concentrations are given in Table 4. The spiked samples were Soxhlet extracted for 16 hours with 350 ml of toluene/acetone (80:20); washed with 40 ml of KOH, 80 ml of high performance liquid chromatography (HPLC) grade water and subsequently with 10 ml of H 2 S O 4 . The solvents were finally removed by rotary evaporation and the samples were reconstituted in 10 ml of DCM/hexane (1:1). Sample cleanup took place in four stages. In the first step, aliquots were passed through a multilayer silica column packed with successive layers of silica gel (basic, neutral, acidic, neutral) and eluted with DCM/hexane (1:1). Sulphur was removed from the samples during the second step by passing the silica extract through a column filled with copper fillings and eluted with 25 ml of hexane. This column was also packed with 25 g of Na 2 S0 4 to remove any residual water. The third cleanup step was via a neutral alumina activated column capped with anhydrous Na 2 S0 4 . The column was first washed with hexane to remove interfering compounds. Further elution with 1:1 DCM/hexane recovered the analytes of interest. Fractionation of the latter mixture was accomplished with an automated HPLC system utilizing a carbon fibre column packed with a 1:12 mixture of activated carbon/filter paper homogenate. With this arrangement the PCDD/Fs are separated from PCBs and other potentially interfering compounds and thus the detection limits of the method are enhanced significantly. Furthermore, this technique permits the separation of PCBs into three different fractions depending on the position of the chlorine atoms on the molecule. The fractionation was performed successively with: I, 20 ml of 5% DCM/hexane; II, 44ml of 50% DCM/hexane; III, 50 ml of 50% ethyl acetate/benzene and IV, 60 ml of toluene in a reverse flow direction. Fraction I contained the Di-Ortho-PCB's, fraction II the Mono-Ortho-PCB's, fraction III the NO-Ortho-PCB's and fraction IV the PCDDs and PCDFs. All three fractions collected from the carbon fibre system were concentrated to less than 10 pi and spiked with the corresponding 13Ci2-labeled method performance standards prior to gas chromatography/high-resolution mass spectrometry analysis (GC/HRMS). The performance standards added to fraction IV were: 13Ci2-l,2,3,4-TCDD and 1 3Cn-1,2,3,7,8,9-HxCDD. For this study, only fraction IV was analyzed by GC/HRMS and the PCBs fractions were collected for future studies. 50 PCDD/PCDF Surrogates Spike Volume (pg) 1 JC,,-2,3,7,8-TCDD 1000 l 3 C 1 9 - l ,2 ,3J ,8 -PeCDD 1000 1 3C,,-l,2,3,6,7,8-HxCDD 1000 1 3C 1 2-l,2,3,4,6,7,8-HpCDD 1000 1 3 C , 9 - O C D D 2000 1 3C 1 2-2,3,7,8-TCDF 1000 1 3C„-l,2,3,7,8-PeCDF 1000 1 3C„-l,2,3,4,7,8-HxCDF 1000 1 3C„-l,2,3,4,6,7,8-HpCDF 1000 Table 4: Composition of internal standard surrogate mixtures used to spike all samples analysed. 51 3.3.4.2. Instrument Analysis and Quantification PCDDs, PCDFs were analyzed by GC/HRMS. The instrument was a VG-Autospec high resolution mass spectrometer (Micromass, Manchester, U.K.) equipped with a Hewlett-Packard model 5890 Series II gas chromatograph and a CTC A200S autosampler (CTC Analytics, Zurich, Switzerland). The GC was operated in the splitless injection mode with a 60 m DB-5 fused silica capillary column (0.25 mm ID. with 0.1 pm film thickness) from J&W Scientific (Folsom, CA). The temperature program for the PCDD/PCDF analysis was as follows: the initial column temperature was held at 100°C for 2 min after injection and increased at 20°C/min to 20°C, then at l°C/min to 215°C, held for 7 min followed by a ramp of 4°C/min to 300°C where it was held for 3 min. The MS was operated at 10,000 resolution under positive EI conditions (35eV electron energy) and data were acquired in the Single Ion Resolving Mode (SIR). Two or more ions, M + and (M+2)+ in most cases, of known relative abundances, were monitored for each molecular ion cluster representing a group of isomers, and two for each of the 13Ci2-labeled surrogate standards. Compounds were identified only when the GC/HRMS data satisfied all of the following criteria: (1) two isotopes of the specific congeners were detected by their exact masses with the mass spectrometer operating at 10,000 resolving power or higher during the entire chromatographic run; (2) the retention time of the specific peaks was within three seconds to the predicted time obtained from analysis of authentic compounds in the calibration standards; (3) the peak maxima for both characteristic isotopic ions of a specific congener coincided within two seconds; (4) the observed isotope ratio of the two ions monitored per congener were within + 15% of the theoretical isotope ratio; (5) the signal-to-noise ratio resulting from the peak response of two corresponding ions was greater or equal to three for proper quantification of the congener. The concentrations of identified compounds and their minimum detection limits (MDLs) were calculated by the internal standard method using mean relative response factors determined from calibration standard runs made before and after each batch of samples were run. The specific compounds analyzed are listed in Table 5. The criteria for identification and quantification, and the quality assurance and quality control measures undertaken for the sample workup and the GC/HRMS analysis of all the 52 PCDD Congeners PCDF Congeners 2,3,7,8-TCDD Total TCDD Homologue 2,3,7,8-TCDF Total TCDF Homologue 1,2,3,7,8-PeCDD Total PeCDD Homologue 1,2,3,7,8-PeCDF 2,3,4,7,8-PeCDF Total PeCDF Homologue 1,2,3,4,7,8-HxCDD 1.2.3.6.7.8- HxCDD 1.2.3.7.8.9- HxCDD Total HxCDD Homologue 1,2,3,4,7,8-HxCDF 1,2,3,6,7,8-HxCDF 2.3.4.6.7.8- HxCDF 1.2.3.7.8.9- HxCDF Total HxCDF Homologue 1,2,3,4,6,7,8-HpCDD Total HpCDD Homologue 1.2.3.4.6.7.8- HpCDF 1.2.3.4.7.8.9- HpCDF Total HpCDF Homologue OCDD OCDF Table 5: Polychlorinated Dibenzo-p-dioxins (PCDDs) and Polychlorinated Dibenzo-p-furans (PCDFs) determined in each sediment sample analyzed. 53 analytes of interest were based on procedures described in the Environment Canada protocols. 3.3.5. Surface Area Samples were first oxidized using a combination of hydrogen peroxide (30%) and sodium pyrophosphate (0.1 M) (Sequi and Aringhieri, 1976) in order to remove organic matter from the samples. This process was carried out in a water bath (70-80°C) for 48-96 hrs; aliquots of H2O2 were added twice daily until oxidation was complete as marked by the cessation of C O 2 evolution. Samples were then rinsed twice in distilled water to remove any residual inorganic salts and dried. Freeze drying, oven drying and oven drying under vacuum were tested as methods of sample drying prior to analysis; good agreement was found between all three methods. A Micromeritics ASAP 2010 surface area analyzer was used to measure surface area by N2 adsorption, using both single and multi point BET (Brunauer, Emmett, Teller) methods (Gregg and Sing, 1982; Mayer, 1993). Prior to analysis, samples were degassed at 350°C for a minimum of 6 hrs. The standard error of the surface area ranged from 2-4%. 3.3.6. 2 1 0 P b Dating 210 Dating of the sediment core was carried out using the Pb method of Smith and Walton (1980) modified after Flynn (1968). One to two grams of sediment was weighed out into acid cleaned microwave digestion vessels, and spiked with Po to allow for normalization of differences between samples during counting and plating (McNee, 1997). The samples were then microwave digested using a combination of H N O 3 , HC1 and HF, to remove organic material, aluminosilicates and silica, and to liberate 210Po from the sediment matrix (McNee, 1997). The digested residue was dried overnight under heat lamps, resusupended in 10% HC1 and digested again. The pH was then brought up to 210 6-9 using N H 4 O H , forming an iron precipitate containing Po, which was stored in 210 ml Nalgene bottles until plating (HDPE). 54 To plate the samples, the iron precipitate was redissolved in 10% HC1, centrifuged, and the supernatant decanted into acid cleaned 250 ml glass beakers. Sodium citrate (25%, 2 ml), NH2OH.HCl (20%, 5 ml) and Bi(N03)3 (10%, 1 ml) were added to the supernatant and the pH was raised to 1.5-2.5 using NH4OH. The solution was stirred and heated to a temperature range of 90-100°C, and a polished silver disk in a Teflon holder was inserted into the solution. Plating of 210Po onto the disks occurred for 4-5 hrs, after which the silver disks were cleaned with cone. HC1 to improve counting efficiency, washed in double distilled water and allowed to air dry. The disks were counted for at least 24 hrs in an Ortec 5 76A Multi-channel Analyzer and Alpha-counter. 3.4. Sediment Core Age Profile: The initial 210Pb dating of the homogenized bulk samples taken from the study core failed to yield a linear chronology. The dating procedure was modified slightly, changing the ratio of sample to 208Po spike, and repeated. Unfortunately significant fluctuation in age was found with increasing core depth, which ultimately prevented meaningful temporal correlation with other data. This dating technique has been successfully applied to other samples recovered from different areas in Howe Sound (MacDonald et al, 1992), and reasons for the apparent failure in this case are unclear, but are further discussed in later sections. 55 3.5. Results: 3.5.1. Bulk Organic Analyses 3.5.1.1. Elemental Composition 3.5.1.1.1. Carbon and Nitrogen Content TOC concentrations range from 0.5-1.7 wt.% (Table 6), the range for TN concentrations is small, 0.04-0.1 wt.%. (Table 6). No clear down core trends exist for either carbon or nitrogen, with both elemental concentrations producing a saw tooth profile when plotted against depth (Figure 1 la,b). 3.5.1.1.2. Organic Carbon/Nitrogen Ratio Corg/N values range from 12-24, with a mean of 15 (Table 6). When plotted against depth (Figure 12), a similar saw tooth pattern to that seen in Figure 11 is evident. The spread of values for C o r g/N is relatively narrow, and a slight overall increase in ratio can be seen with increasing depth (Figure 12). Figure 13 shows a moderate positive correlation (r2 = 0.7) between TOC and TN (positive y-intercept suggests the presence of inorganic nitrogen), even though minor scattering beyond the regression line is evident. 3.5.1.2. Organochlorine Compounds 3.5.1.2.1. PCDD/Fs Total PCDD shows neither enrichment nor depletion with increasing sediment depth (Figure 14a), but rather enrichment at specific sediment depths, most notably in the 14-16 cm (200 pg/g) and the 46-48 cm (700 pg/g) horizons (Table 7). TCDD (Tetra-), PeCDD (Penta-), HxCDD (Hexa-), HpCDD (Hepta-) and OCDD (Octa-) homologues all share the same concentration profile as total PCDD, fluctuating irregularly with depth (Figure 15). HxCDD is present at significantly higher 56 Sediment Interval (cm) Corg (wt.%) N (wt.%) Corg/N 2 Surface Area (m /g) DF 0-1 1.00 0.08 12.88 4.21 DF 1-2 1.38 0.10 13.78 6.13 DF 2-3 0.93 0.07 13.43 4.9 DF 3-4 0.57 0.05 11.99 2.43 DF 4-5 0.71 0.05 14.04 3.17 DF 5-6 0.49 0.04 12.61 2.88 DF 6-7 1.09 0.08 13.34 8.47 DF 7-8 0.96 0.06 15.25 3.32 DF 8-9 1.17 0.08 15.43 3.34 DF 9-10 1.11 0.09 12.41 5.8 DF 10-12 1.21 0.08 15.15 2.49 DF 12-14 0.82 0.05 16.03 2.53 DF 14-16 1.52 0.09 17.42 5.86 DF 16-18 1.24 0.09 13.11 10.94 DF 18-20 1.18 0.08 14.66 9.33 DF 20-22 0.91 0.06 14.08 6.74 DF 22-24 0.95 0.06 16.08 5.94 DF 24-26 0.51 0.04 11.83 4.05 DF 26-28 0.79 0.06 12.55 3.65 DF 28-30 0.73 0.06 13.16 5.44 DF 30-32 0.68 0.05 12.52 4.6 DF 32-34 0.75 0.05 14.99 3.92 DF 34-36 0.92 0.06 16.08 4.2 DF 36-38 1.32 0.08 17.43 5.67 DF 38-40 1.56 0.08 19.07 5.45 DF 40-42 0.80 0.05 16.67 3.36 DF 42-44 1.16 0.07 16.39 5.67 DF 44-46 1.33 0.08 17.24 7.63 DF 46-48 1.65 0.09 18.10 7.14 DF 48-50 1.71 0.07 23.86 11.96 DF 50-52 1.40 0.07 20.37 N / A 6: Organic Carbon (Corg), Total Nitrogen (TN), Carbon/Nitrogen Ratio (Corg/N) and Surface Area (SA) for bulk sediment samples from the core taken adjacent to Woodfibre pulp Mill, Howe Sound, British Columbia, subsampled every centimetre for the first ten centimetres and every two centimetres thereafter. 57 10 20 30 40 50 60 Corg (wt.%)] -Corg (wt.%) vs. Depth (cm) Total Nitrogen (wt.%)| 0 0.02 0.04 0.06 0.08 0.1 0.12 10 30 40 50 60 B| -Nitrogen (wt.%) vs. Depth (cm) Figure 11: Downcore variations in Organic Carbon (Corg; A) and Total Nitrogen (B) for bulk sediment samples. Note the sawtooth profile with no consistent downcore trend. 58 Figure 12: Downcore variation in Organic Carbon/Total Nitrogen ratio (Corg/N). The trend line depicts a gradual increase in Corg/N ration with increasing sediment depth. 59 60 20 40 Cone. (pg/g) | 200 400 600 800 -TOTAL PCDD 20 30 4 45 50 Cone. (pg/g) | 50 100 150 200 B -TOTAL PCDF Figure 14: Downcore variation in Total Polychlorinated Dibenzo-p-dioxin (PCDD; A) and Total Polychlorinated Dibenzo-p-furan (PCDF; B) for bulk sediment samples. 61 PL, Q X Q Q X Q Q U x X oo co t-. vq cn ~ cn cn oo vo ^ » oo M oo in in oq cn vd tN cn cn as CN ^t' m u-i cn \o Ov -<t C N C N cn TT CN <—1 CN '—' 3 r— vo cn as ** cn m TJ- I> oo p--^ o ^ m C N o O as \o vo C N C N O o C N o C N cn O oo as C N cn cn m oo ^ vo vo o\ C N ^ vo cn !G ^ C N ^ » 2 Os cn oo N ^ vi r~ ir> O N oo VO CN C N VO cn in ^ ^ VO Q\ Tj-oo oo in vq in ' 1 OO O in vo VO r- a\ o vd o oq Os cn o in O CN Ov r- r~ oq oq -sr_ cN cn © <-i C N cn in cn o vo oo vo O r - l I T i i i O T t ta ta i n m o o r ^ v o _ 0 \ o o —<" r-" — J ^ O ^ O O O r-> n c n c N > - H o o o o m o o in oo M i t C N c n C N O N O V OO vo o d ^ © ^ H ' m d cn ns cN-rrvomi2'<ti~~o\cNcN t ^ P 1 / 1 c n ^ : r ~ : r i v o . T : 1 : o \ t c i " m t ^ J ( f ) ^ v 5 ( C ) M t— r- as ~ C N cn m C N vo in IT) ~ in cn t CN O CN _+ cn cn oo ™ r-H VO *•* OO O O O VO — V C f N V O c N v C C N O O 2 - H M N « f i T f ~ i i • • i i i e i ^ o ^ - o ^ r o v © ta ta ta A mm mm mm Q Q Q Q s fa s " 5 s s S 0 0 K •2 2 K ^> VJ C <a V J I Q S a. O V j 0 0 ^ s 5-62 50-1 |—•—TCDD — B — PeCDD — A — HpCDD — X — O C D d ] Figure 15: Downcore variation in dioxin homologue concentration for bulk sediment samples. Inset shows HxCDD, which is present at significantly higher concentrations than the other homologues. 63 L concentrations than the other dioxin homologues (Figure 15, Inset). If HxCDD is ignored, a positive relationship exists between increasing homologue concentration and the number of chlorine atoms present in the homologue molecular structure (Figure 15). Total PCDF (Figure 14) has an identical depth profile to TCDF (Figure 16 Inset). Overall concentrations of furan homologues are on the order of four times lower than their dioxin counterparts (Table 7). TCDF is the most concentrated furan homologue, present in concentrations approximately six times that of the next most concentrated homologue, HpCDF (Table 7). Unlike the dioxin homologues, furan homologues do not show the same relationship between relative concentration of a given homologue and its molecular chlorination (Figure 16). The downcore concentration profiles of individual PCDD/F (Figures 15 and 16) homologues as well as those for total PCDD/F (Figure 14) concentration are similar to that of TOC (Figure 11a), with corresponding peaks in concentration at 15 cm, 35 cm and 45 cm. 3.5.1.3. Surface Area Surface area values for bulk sediment samples range from 2.5-12 m /g (Table 6). Although peaks in surface area values do correlate with some increased TOC concentrations at certain depth intervals, a plot of TOC vs. surface area (Figure 17) shows only a moderate positive correlation (r = 0.4). Significant scatter above and below the regression line, with the majority of samples falling below the regression line, suggests lower than expected surface area values for their apparent TOC concentration. 3.5.1.3.1. PCDD/Fs and Surface Area When plotted against surface area, total PCDD, PCDF and the five homologues analyzed for each, show almost identical relationships (Figure 18). A low to moderate correlation exists between surface area and bulk concentration for all of the homologues analyzed, with r2 varying from 0.23 to 0.54. For every homologue analyzed, the 9 samples from the 0-42 cm core interval form a diffuse cluster on the left of the plots 64 Cone, • (pg/g)| CL CD Q 40 45 Cone. (pg/g)| 0 20 40 60 80 100 120 140 - T C D F 45 • 50 -- PeCDF — A — HxCDF — X — HpCDF — * — O C D F Figure 16: Downcore variation in furan homologue concentration for bulk sediment samples. Inset shows TCDF, which is present at significantly higher concentrations than the other homologues. 6 5 66 |Conc, (pg/g)| TOTAL PCDD Linear (TOTAL PCDD) | | • TOTAL PCDF Linear (TOTAL PCDF) j • • • = # s * y = 0.127x + 4.5115 R2 = 0.2304 •> •• (pg/g)| TCDD Linear (TCDD)] | • TCDF Linear (TCDF) [ = 0.1014X + 4.2786 H2 = 0.4341 Cone. (pg/g)l -Linear (PeCDD) | | • PeCDF Linear (PeCDF) [ 10 Ui 8 Si 6 < 4 co 2 0 • _ —• * y = 0.0567x +4.0715 RJ = 0.5373 • (P9/g)| • HxCDD Linear (HxCDD) | • HxCDF Linear (HxCDF) | 10 oi 8 6 < 4 CO 2 0 y = 0.0567X4-4.0715 R2 = 0.5373 30 40 Cone. (pg/g)l | • HpCDD Linear (HpCDD) | [ • HpCDF Linear (HpCDF) | • -——~- * Iv = 0.0406X + 4.0723 ^ Ra = 0.5114 20 40 60 80 jconc. (pg/g)] • OCDD Linear (OCDD) | Figure 18: Plot of Surface Area (SA) vs. dioxin, furan and total homologue concentration for bulk sediment samples. (Figure 18), whilst the tenth sample which represents the 46-48 cm depth interval, plots to the right due to the significantly higher concentrations of individual homologues found in this sample. Removing the high concentration 46-48 cm sample from the plot does not significantly alter the correlation between surface area and concentration. The plots shown in Figure 18 also share a common y-intercept value of approximately 4 m2/g, which theoretically suggests that a threshold surface area value exists, below which neither dioxins nor furans are adsorbed to particle surfaces. 3.5.2. Size Fractionated Organic Analyses: 3.5.2.1. Elemental Composition 3.5.2.1.1. Carbon and Nitrogen TOC values for the four samples selected for size fractionation, ranged from 0.3-11 wt.% (Table 8). TN concentrations range from 0.03-0.2 wt.% (Table 8). For the four samples analyzed, the > 63 um fraction contains the highest concentration of both TOC (5-11 wt.%) and TN (0.15-0.2 wt.%; Figure 19a, 19b). The < 2 um fraction contains the second highest concentration of TOC and TN, ranging from 1-3 wt.% and 0.8-0.2 wt.% respectively (Table 8; Figure 19a, 19b). The intermediate size fractions, 2-10 um, 10-20 um and 20-63 um contain varying amounts of TOC and TN at lower concentrations to those observed in the < 2 um and > 63 um fractions (Table 8; Figure 19a, 19b). Both DF 14-16 and DF 46-48 have approximately equal amounts of TOC and TN in the 2-10 um and 10-20 um fractions and the lowest concentrations of TOC and TN in the 20-63 um fraction. DF 20-22 shows the opposite, approximately equal amounts of TOC and TN in the 2-10 urn and 10-20 um fractions, and higher concentrations in the 20-63 um fraction, whilst DF 34-36 shows the lowest concentrations of TOC and TN in the 10-20 um fraction and approximately equal amounts in the 2-10 urn and 20-63 um fractions. 68 0 0 O t: 3 </3 0 0 O u o U c -4—• u cd PL, .15 c73 •a on 2§ O C N O N ^ C N r- ^ vo i£ «o C N ' C N m >t O oo h p —; -tf r-; cn vo O N ^ vd r n - H (VJ N cn r-in d o vo cn cn t M M o d o o cn C N oo o O N oo d d C N ^ ^ ^ ^ 8 O O A ~^ CN vo •4 ta Q C N r- oo o O N cn r~ VD |5 m (NI ^ io ^ >—i vo r~ oo ; r~; C N r~; ri d in ^ N C O cn O N oo C N oo T—i C N cn in O O O O —< d o d d d O N » -4 vo r~~ ^ oo f~ in | C N cn r~-^ d d d io C N ° ^ <\-, < N « 2 ~ ^ C N A CN CN © cN ta Q 2 i n M to °°. vo m O >J-) C N vo cn C N O N V O CN cn io vo - H o T J -q in H r~: —; C N cn -3- in C N -rf O C N cn r~ O O O — i ci d> d> d <5 <—' r-- O N m O N O N V O —< oo CN in vq vq ^ d d d io C N VO • ta Q CN co r-vq in cn ^ co vd CN O N io r~ — in co C N O N cn •— ^ N ( S vo vo r~ vo co — i o o o d> d> c5 d> cn vo O CN d •ri- cn C N in co - H vo r- s 1 cn C N ^ °^ ^ ^ v2 ~ ^ C N 00 I VO ta Q V -ft 69 DF 14-16 DF 20-22 Sample #| DF 34-36 DF 46-48 I>63 microns • 20-63 microns 010-20 microns B2-10 microns H<2 microns DF 14-16 DF 20-22 DF 34-36 DF 46-48 Sam pie #[ l>63 microns •20-63 microns 010-20 microns 02-10 microns B<2 microns Figure 19: Distribution of Organic Carbon (Corg; A) and Total Nitrogen (TN; B) for four selected samples, size fractionated into five fractions: <2jlm, 2-Wjum, 10-20jum, 20-63fMn and >63)Jm. 70 3.5.2.1.2. Organic Carbon/Nitrogen Ratio Corg/N values for size fractionated samples range from 13-53, with a mean of 23, indicating a dominant terrestrial signature for the organic matter present in the samples. The Corg/N ratio increases with increasing grain size (Table 8). A significant increase in Corg/N values occurs between the 20-63 um fraction and the > 63 um fraction. Figure 20 shows TOC plotted against TN with the > 63 um fraction grouped separately from the remaining size fractions. The separation of the > 63 um data from the other size fractions, which all fall on a single regression line (r2 = 0.8; Figure 20), is the result of significantly higher organic carbon contents in that fraction. 3.5.2.2. Surface area Surface area values for size fractionated samples range from 1.5-22 m2/g, with highest values found in the < 2 um fraction (16-22 m /g) and lowest values in the 20-63 pm fraction (1.5-2.4 m2/g; Table 8). In Figure 21a, which shows the TOC concentrations for individual size fractions plotted against surface area, significant clustering occurs amongst each size fraction. Two end members exist, the < 2 um fraction which has high surface area values compared to TOC content (Table 8), and the > 63 um fraction which has high TOC content and low surface area values (Table 8). The remaining size fractions, 2-10 um, 10-20 um and 20-63 um, cluster between the two end members. Figure 21a suggests that no relationship between surface area and TOC content exists (r < 0.1), and that organic matter is not adsorbed to sediment particle surfaces. However, if data from the > 63 um fraction is considered as outliers (because organic matter in this fraction is probably detrital, occurring as discrete particles, and therefore independent of surface area), then the correlation between TOC content and surface area is significantly improved. Figure 21b shows the same data with the > 63 um fraction omitted, producing and r value of 0.51 which suggests a direct relationship between surface area and TOC concentration via adsorption of organic matter. 71 72 Figure 21: A) Plot of Surface Area (SA) vs. Organic Carbon (Corg) for size fractionated samples. The >63/Jm fraction plots to the right of the graph due to its high Corg content and low surface area. B) Plot of surface area and Corgfor size fractionated samples with the >63jtlm fraction removed. The plot has a moderate positive correlation, r =0.5. 73 3.5.2.3. Organochlorine Compounds 3.5.2.3.1. PCDD/Fs The majority of trends observed in individual dioxin and furan congeners with respect to grain size and concentration are represented by their parent homologues. Thus concentrations are discussed here with reference to homologues rather than to each individual congener. 3.5.2.3.1.1. DF14-16 Dioxin and furan concentrations do not vary with grain size in this sample. The highest concentrations of dioxins and furans are found in the > 63 um fraction. Relative concentrations of the different homologues in the dioxin family are similar (<100 pg/g; Table 9; Figure 22a) except for HxCDD which is present in concentrations more than double that of the average concentration of the other four homologues (Figure 22a). For HxCDD, PeCDD and TCDD, the highest concentrations occur in the > 63 um fraction, dropping dramatically in the 20-68 um fraction before peaking again in the 10-20 um fraction (Figure 22a). Concentrations then progressively decrease in the two finest fractions. HpCDD and OCDD also have their highest concentrations in the > 63 um fraction, drop off dramatically in the 20-68 um fraction, gradually increasing through the finer fractions, peaking at 23.08 pg/g and 33.77 pg/g for HpCDD and OCDD respectively (Figure 22a). However, HpCDD and OCDD concentrations in the < 2 um fraction are approximately 1/3 of those in the > 63 um fraction (Table 9). The trend for TCDF and PeCDF is identical to that of HxCDD, with levels of TCDF running approximately four times those of the other furan homologues (Table 9). HxCDF, HpCDF and OCDF all peak in the > 63 um fraction, drop to a low in the 20-68 um fraction, and increase again in the < 2 urn (Figure 22b). Total PCDD and PCDF concentrations are very similar to the trends in the individual homologues (Figure 22c). Concentrations peak in the > 63 urn fraction (499 pg/g dioxins, 120 pg/g furans) before dropping to a low in the 20-68 um fraction (119 74 TOTAL PCDF 24.27 34.52 40.17 21.64 119.65 39.97 23.81 19.63 32.57 122.87 15.8 13.34 12.97 15.17 50.09 253.03 158.34 163.83 158.24 630.63 OCDF | 1.91 1.78 0.98 0.86 4.2 3.54 2.15 0.67 1.74 5.4 1.24 0.74 0.61 0.56 1.63 18.14 6.67 4.01 5.28 13.97 HpCDF | 5.56 4.6 3.05 9 Al 11.09 9.46 5.17 2.21 4.6 12.79 3.7 2.32 2.01 1.95 5.43 48.11 22.84 14.59 13.98 44.36 HxCDF ] 3.72 2.9 3.05 1 1 Q 9.51 4.75 2.1 1.44 2.79 8.02 2.65 1.76 1.46 2 17 4.35 28.6 12.95 10.51 6.92 38.41 PeCDF | 3.99 5.62 6.5 9 1A 17.94 3.82 2.11 2.28 3.7 11.86 2.07 1.79 1.73 2.19 5.61 22.85 12.52 13.48 12.72 57.23 TCDF | 9.11 19.61 26.59 1 A 19 14.JO 76.9 18.4 12.28 13.03 19 74 84.81 6.15 6.73 7.14 8 29 33.07 135.32 103.37 121.23 119 34 476.65 TOTAL PCDD | 150.53 202.28 284.44 118.68 498.88 216.22 94.66 83.87 129.17 538.45 88.74 66.51 55.96 63.37 183.7 1677.92 822.76 695.8 647.8 1996.2 OCDD | 33.77 23.56 20.9 1 fx fx 1 D.D 93.69 37.55 13 10.67 23.77 133.62 19.72 12.01 9.97 11 77 29.42 214.12 74.81 58.37 52.77 200.92 HpCDD | 23.08 22.56 26.27 14.0 76.49 28.42 10.56 9.37 1 / JJ 122.04 15.06 10.54 8.73 i c\ cn 30.19 159.89 62.9 49.88 AO QQ 170.34 HxCDD | 82.87 107.75 133.57 51.77 243.31 141.65 65.4 56.15 7fi ^ 240.11 50.07 39.55 32.44 ~Kf% A\ 110.04 1257.14 654.83 551.35 1480.52 TCDD PeCDD | 8.06 24.61 52.19 16.77 42.58 6.43 3.88 4.54 fx 7Q 22.81 3.25 3.21 3.37 i fn 9.22 37.29 23.59 26.47 9*5 1A 99.19 TCDD PeCDD | 2.75 23.8 51.51 18.94 42.81 2.17 1.82 3.13 19.87 0.64 1.2 1.45 1 Aft 4.83 9.47 6.63 9.73 45.23 Size Fraction (Micrometres) | <2 2-10 10-20 20-68 >68 <2 2-10 10-20 20-68 >68 <2 2-10 10-20 20-68 >68 <2 2-10 10-20 20-68 >68 Sediment Interval (cm) 1 DF 14-16 DF 20-22 DF 34-36 DF 46-48 I f Size Fractions (Microns)) -TCDD • - -Q • • PeCDD • •HxCDD — -K — -HpCDD — -X — OCDD Size Fractions (Microns)| -TCDF - - <3 • • PeCDF — -A- - HxCDF - - X - -HpCDF - -X - -OCDF I f T3-- a • Size Fraction (Microns)l -TOTAL PCDD - -Q- -TOTAL PCDF Figure 22: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 14-16cm depth interval. The overall trend is of decreasing concentration with progressively finer grain size. 7 6 pg/g dioxins, 22 pg/g furans). Both dioxins and furans peak again in the 10-20 pm fraction, before tailing off to another low in the < 2 pm fraction, 151 pg/g for dioxins and 24 pg/g for furans (Table 9; Figure 22c). 3.5.2.3.1.2. DF 20-22 Dioxin homologues peak in the > 63 pm fraction with HxCDD present in concentrations almost double that of the second most concentrated homologue, OCDD (HxCDD, 240.13 pg/g; OCDD, 133.62 pg/g; Figure 23a). Concentrations drop to a low in the 10-20 pm fraction before peaking again in the < 2 pm fraction in 4 of the homologues (PeCDD, 6.43 pg/g; HxCDD, 141.65 pg/g; HpCDD, 28.42 pg/g; OCDD, 37.55 pg/g). TCDD drops from 3.18 pg/g in the 2-10 pm fraction to 2.17 pg/g in the < 2 pm fraction. Furan homologues also peak in the > 63 pm fraction, with TCDF present in significantly higher concentrations than all other homologues (TCDF, 84.81 pg/g; HpCDF, 12.79 pg/g; Table 9; Figure 23b). All five homologues reach a low concentration in the 10-20 pm fraction before increasing gradually through to the < 2 pm fraction. The exception to this trend is HpCDF, which shows a sharp increase in concentration from the 10-20 pm fraction (2.21 pg/g) to the 2-10 pm fraction (9.94 pg/g), before dropping to 9.46 pg/g in the < 2 pm fraction (Figure 23b). Both dioxins and furans have their highest total homologue concentrations in the > 63 pm fraction (538 pg/g dioxins; 123 pg/g furans). Dioxin concentrations peak again in the < 2 pm at 216 pg/g, whilst furans show a more gradual increase in concentration from the 10-20 pm fraction (20 pg/g) to the < 2 pm fraction (40 pg/g; Figure23c). 3.5.2.3.1.3. DF 34-36 HxCDD, HpCDD and OCDD all have bimodal concentration distributions peaking in the > 63 pm fraction (HxCDD 110.04 pg/g; HpCDD 30.19 pg/g; OCDD 29.42 pg/g), dropping sharply in the 20-68 pm fraction (HxCDD 36.41 pg/g; HpCDD 10.07 77 V' . •s s 10-20' Size Fraction (Microns)| | • TCDD • - -P • • PeCDD — -A- - HxCDO K — HpCDD — -» — OCDD] Size Fraction (Microns)j -TCDF - - -Q - • PeCDF — -A— - HxCDF — -M — HpCDF — -* — OCOF Size Fraction (Microns) — TOTAL PCDD — H • TOTAL PCDF Figure 23: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 20-22cm depth interval. Peak concentrations occur in the coarsest fraction. Dioxin concentration increases in the finest two size fractions, whilst furan concentration remains relatively constant throughout. pg/g; OCDD 11.77 pg/g), and reaching a low in the 10-20 pm fraction (HxCDD 32.44 pg/g; HpCDD 8.73 pg/g; OCDD 9.97 pg/g) before peaking again in the < 2 pm fraction (HxCDD 141.65 pg/g; HpCDD 28.42 pg/g; OCDD 37.55 pg/g; Figure 24a). HxCDD, as in samples DF 14-16 and DF 20-22, is present in concentrations three times greater than OCDD, which has the next highest concentration (Table 9). TCDD and PeCDD also have their highest concentrations in the > 63 pm fraction (4.83 pg/g and 9.22 pg/g respectively). However, TCDD shows a steady decrease in concentration across finer fractions, reaching the lowest concentration in the < 2 pm fraction (0.64 pg/g). PeCDD has its lowest concentration in the 2-10 pm fraction (3.21 pg/g) rising only by 0.04 pg/g to 3.25 pg/g in the < 2 pm fraction (Figure 24a). Furan homologues show similar trends to dioxin homologues. TCDF peaks in the > 63 pm fraction (33 pg/g) falls to 8.3 pg/g in the 20-68 pm fraction, before steadily decreasing to 6.15 pg/g in the < 2pm fraction. PeCDF, HxCDF, HpCDF and OCDF all have bimodal concentration distributions, with peaks of similar concentration in the > 63 and < 2 pm fractions (Figure24b; Table 9). Total homologue concentrations for PCDD and PCDF show clear differences. Both total PCDD and PCDF have highest concentrations in the > 63 pm fraction, 184 pg/g and 50 pg/g respectively. Total PCDD shows a distinct increase in concentration across the 10-20, 2-10 and < 2 pm fractions, peaking at 89 pg/g in the < 2 pm fraction (Figure 24c). Total PCDF shows only a minor increase of 2.83 pg/g across the same size fractions (Figure 24c). 3.5.2.3.1.4. DF 46-48 All five homologues show peak enrichment in the > 63 pm fraction (Table 9) with the exception of OCDD, the only homologue analyzed that has the highest concentration in the < 2 pm fraction (214.12 pg/g). OCDD, HpCDD and HxCDD all show increases from the 20-68 pm fraction through to the < 2 pm fraction, with a sharp increase between the 2-10 and < 2 pm fractions. TCDD decreases with finer grain sizes, with only a slight increase from the 2-10 pm fraction (6.63 pg/g) to the < 2 pm fraction (9.47 pg/g; Figure 25a). PeCDD shows a similar concentration distribution to that of TCDD. As observed in 79 g Size Fraction (Microns)| | • -TCDD - • Q • - PsCDD — -A— - HxCDD K — HpCDD — - » — OCDD | >63 20-68 10-20' 2-10' <2 Size Fraction (Microns) Figure 24: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 34-36cm depth interval. Peak concentrations occur in the coarsest fraction. Some dioxin and furan homologues increase in concentration in the finest two size fractions, whilst other homologues show steady decrease in concentration. X A. Size Fraction (Microns)| • Size Fractions (Microns)l -TCDO B — PeCDD - - - - HpCDD — -M — OCDD | A Size Fraction (Microns)] • -O • • PaCOF — -j- - H«CDF K — HpCDF — •» — OCDF | c a - * >63 20-68 10-20' 2-10' <2 Size Fraction (Microns)| —TOTAL PCDD B — TOTAL PCDF Figure 25: Plot showing the changes in concentration of dioxins (A), furans (B) and total homologues (C) between different size fractions at the 46-48cm depth interval. The majority of dioxin and furan homologues show significant increase in concentration in the finest three fractions. Insets show homologues present at concentrations significantly higher than other homologues. samples DF 14-16, DF 20-22 and DF 34-36, HxCDD is present in significantly higher concentrations, almost seven times that of the next most concentrated homologue, OCDD (Table 9). It should be noted that three out of the seven congeners analyzed, 123789-HxCDD, 1234678-HpCDD and OCDD (Congener = Homologue) have higher concentrations in the < 2 pm fraction than the < 68 pm fraction. The concentration distribution for HpCDF and OCDF are similar to that of OCDD in that they are the only Furan homologues to have their highest concentrations in the < 2 pm fraction (Table 9). HpCDF and HxCDF show increasing concentrations from the 20-68 pm fraction through to the < 2 pm fraction, whilst OCDF decreases in concentration from the 20-68 pm fraction to the 10-20 pm fraction, before increasing again in the < 2 pm fraction (Figure 25b). TCDF and PeCDF both have peak concentrations in the > 63 pm fraction (477 and 57 pg/g respectively). However, unlike other homologues, the 10-20 pm fraction has slightly higher concentrations than the 20-68 and 2-10 pm fractions (Figure 25b; Table 9). The trend seen in TCDF and PeCDF is also observed in total PCDF concentrations (Figure25c), with concentrations in the < 2 pm fraction (253 pg/g) being approximately one third of those in the > 63 pm fraction (631 pg/g). Total PCDD concentrations (Figure 25c) show a peak of 1996 pg/g in the > 63 pm fraction, drop to 648 pg/g in the 20-68 pm fraction, increase steadily to 823 pg/g in the 2-10 pm fraction, before jumping to 1678 pg/g in the < 2 pm fraction. In contrast to PCDF, concentrations in the < 2 pm fraction are approximately 85% of those in the > 63 pm fraction for PCDD. 3.5.2.3.2. PCDD/F's and Surface Area Relationships between surface area and homologue concentration in size fractionated samples are highly variable and range from no correlation at all, to strong positive correlation in some samples. Due to the large number of possible permutations, 48 plots for 4 samples (5 Dioxin homologues, 5 Furan homologues and Total PCDD and PCDF for each sample), only selected graphs are presented (Figure 26a-j). In all cases, the > 63 pm fraction has 82 been omitted from the graphs, due to its high homologue concentration and low surface area, which results from the presence of particulate (unabsorbed) organic matter. Table 10 contains the r values for all of the correlations between surface area and t 2 homologue concentration, showing both r values that represent all 5 size fractions analyzed, and values that include only the 4 finest fractions (> 63 pm fraction omitted). 3.5.2.3.2.1. DF 14-16 TCDD and TCDF both show negative correlations with surface area (r2 = 0.48; Table 10), becoming more concentrated with coarser grain size/lower surface area. A similar relationship exists for PeCDD and PeCDF, with PeCDF concentration showing almost no correlation with surface area at all. Good positive correlations are observed in HxCDF, HpCDF and OCDD/F. HxCDD and HpCDD concentrations show very low correlation with surface area (HxCDD, r2 =0.009; HpCDD, r2 = 0.09), whilst HxCDF and HpCDF concentrations have an r values of 0.53 and 0.8 respectively, suggesting a link between increasing surface area and higher homologue concentrations. OCDD/F have r2 values of 0.96 and 0.64 respectively, indicating a strong relationship between surface area and homologue concentration (Figure 26a,b). Total homologue concentrations for PCDD and PCDF do not correlate with surface area, showing slight negative correlations (r2 = -0.1; Table 10). The majority of the regression lines for the observed positive correlations in this sample do not pass through the origin, as is usually the case when OM concentration is plotted against surface area (Figure 17), but rather have a negative y-axis intercept value. 3.5.2.3.2.2. DF 20-22 No correlation exists between surface area and TCDD and TCDF concentrations in this sample (TCDD, r2 = 0.32; TCDF, r2 = 0.2; Table 10). However moderate to good correlations between surface area and homologue concentration do exist for HxCDD/F, HpCDD/F and OCDD/F. PeCDD and PeCDF both show only weak correlations between surface area and concentrations with r values of 0.15 and 0.3 respectively (Table 10). 83 20 15 S E. 10 < Ui 5 0 y = 0.9323x- 15.58 R2 = 0.9589 10 15 20 25 30 . 35 40 Cone. (pg/g)| • OCDD 14-16 Linear (OCDD 14-16) 20 15 Si 10 < Ui 5 0 y = 10.32x- 7.7441 R2 = 0.6411 • V 0.5 Cone. (pg/g)l • OCDF 14-16 —Linear (OCDF 14-16) B y = 0.5789x- 10.675 R2 = 0.5817 • 250 • (P9/g)| • TOTAL PCDD 20-22 —Linear (TOTAL PCDD 20-22) | Q TOTAL PCDF 20-22 ——Linear (TOTAL PCDF 20-22) D y=3.1782x- 26.767 R2 = 0.9305 10 12 14 16 Cone. (pg/g)| • HpCDD 34-36 ^ —Linear (HpCDD 34-36) • HpCDF 34-36 —Linear (HpCDF 34-36) y = 0.6161x-33.784 Ft2 = 0.921 • y = 3.995X - 48.696 R2 = 0.3693 y 4r • (P9/g)j c. (pg/g) | • TOTAL PCDD 34-36 ^—Linear (TOTAL PCDD 34-36) • TOTAL PCDF 34-36 —Linear (TOTAL PCDF 34-36) [ |_| y = -0.9145x + 18.003 R2 = 0.0464 • • • 25 ^ 2 0 e I15 •2J5 0 y = 0.8232X - 2.567 R2 = 0.9936 10 12 10 15 20 25 30 35 • (pg/g)| • (pg/g)| • TCDD 46-48 ^—Linear (TCDD 46-48) • HxCDF 46-48 —Linear (HxCDF 46-48) Figure 26: A-J) Selected plots of Surface Area (SA) vs. homologue concentration for size fractionated sediments from the 14-16cm, 20-22cm, 34-36cm and 46-48cm depth intervals. 84 TOTALPCDF -0.11 -0.11 0.58 0.01 0.37 -0.11 0.9 0.03 | OCDF | 0.64 0.00005 0.58 0.21 0.99 0.06 0.9 0.74 HpCDF J 0.8 0.002 0.85 0.29 0.99 0.01 0.96 0.66 HxCDF 0.53 -0.004 0.81 0.15 0.58 -0.004 0.99 0.35 | PeCDF -0.02 -0.09 0.28 0.004 0.06 -0.12 0.88 0.03 [ TCDF | -0.47 -0.18 ~ O o -0.65 -0.18 0.37 0.0003 | TOTAL PCDD | -0.07 -0.13 0.84 0.05 0.92 0.02 0.96 0.4 | OCDD | 0.96 -0.007 0.71 0.02 0.94 0.008 0.95 0.62 | HpCDD | 0.09 -0.05 0.76 0.01 0.93 -0.01 0.96 0.52 [ HxCDD | -0.009 -0.08 0.92 0.15 0.9 -0.03 0.96 0.41 | PeCDD | -0.34 -0.39 0.14 0.0004 -0.32 -0.16 0.8 0.02 | TCDD | -0.49 -0.52 -0.27 -0.01 -0.98 -0.03 -0.05 -0.002 [# of Size Fractions | >n i n Sediment Interval (cm) 1 DF 14-16 DF 20-22 DF 34-36 DF 46-48 tu •S SO tU as tu a so Si s tu p e .2 s ° ^ I s A to "XJ <U S to tu tU to a So to 1 do S •2 5 c s o a GO 3^ •S to e to to SS to s to tu 6, 13 o> <p -S tu -c> S a c <U cs &o a to "Q a a Co tO •5 Co e o <o - « S 1 2 tU a tu ^5 s tu tu tu -o c o tU cu to c tu > e »3 to Si s" &0 "3 CU ^ tu a cu ^ s 2 tu cu •4^ &C tu tu oj s a to tu Total PCDD and PCDF also show good positive correlations (PCDD, r2 = 0.84; PCDF, r = 0.6; Table 10). However, there is no reasonable spread of data points along the regression line and a significant separation exists between the < 2 pm fraction and the other 3 size fractions (Figure 26c,d). 3.5.2.3.2.3. DF 34-36 Significant negative correlations exist for both TCDD and TCDF. TCDD exhibits an almost perfect negative correlation with surface area (r2 = 0.99; Table 10) suggesting that TCDD is more concentrated in coarser grained, lower surface area sediments. PeCDD also shows a negative correlation (r2 = 0.32; Table 10); PeCDF shows almost no correlation at all between surface area and homologue concentration (Table 10). HxCDD/F, HpCDD/F (Figure 26e,f) and OCDD/F show good correlations between surface area and concentration (Table 10), however all of these plots have significant negative y-intercepts, suggesting that not all of each compound is necessarily related to surface area. Both total PCDD and PCDF show positive correlations between surface area and concentration of 0.92 and 0.37, respectively. However, as observed in Hex-, Hept- and Octochlorinated homologues in this sample, the regression lines do not pass through or close to the origin (Figure 26g,h). 3.5.2.3.2.4 DF 46-48 The correlation between surface area and homologue concentration in this sample is very good (Table 10), with the exception of TCDD, which has a slight negative correlation (r = 0.05; Table 10; Figure 26i), and TCDF, which has an r value of 0.32. HxCDD/F, HpCDD/F and OCDD/F all show excellent correlations between surface area and homologue concentration with all of the regressions passing close to, or through the origin, suggesting a strong link between the two parameters. HxCDF shows perhaps the 86 best relationship between these parameters for any of the homologues analyzed in all 4 samples (r2 = 0.99; Table 10; Figure 26)). Total PCDD and PCDF both show good correlations (PCDD, r2 = 0.96; PCDF, r2 = 0.9; Table 10), but once again have large negative y-intercept values, especially in PCDF. This is also the case for PeCDD and PeCDF. 3.5.2.3.3. PCDD/F and Organic Matter Good correlation exists between PCDD/F and OM concentration in both bulk and size fractionated sediments. Figure 27a shows TCDD through OCDD plotted against OM concentration for size fractionated samples. TCDD has the weakest correlation, r2 = 0.28, whilst HpCDD has the strongest correlation, r2 = 0.63. Figure 27b depicts the same relationship, without the > 63 um fraction, which was omitted based on previous data that suggested that unlike finer fractions, it is not related to surface area, r2 values are higher for HxCDD through OCDD (r2 = 0.8; Figure 27b), whilst the strength of the relationship decreased for TCDD and PeCDD. Identical changes in relationship strength were also observed between organochlorine and organic matter in Furans when the > 63 um fraction was removed (not shown). 87 250 -, 2 4 6 8 10 Corg (wt.%)| A TCDD X PeCDD • HpCDD • OCDD -Linear (HpCDD) - Linear (OCDD) - Linear (TCDD) Linear (PeCDD) 12 70 60 50 If 40 30 A 20 10 4 • R 2 = 0.6872 ^ ^ ' _ — T — — " FT = 0.7399 0 2 4 1 6 8 10 12 Corg (wt.%)| • PeCDF A HxCDF X HpCDF X OCDF Linear (PeCDF) - - Linear (HpCDF) -Linear (OCDF) Linear (HxCDF) Figure 27: A) Plot showing the correlation between dioxin and furan concentration and organic matter concentrations in size fractionated sediments. Inset plots are those congeners with concentrations that are significantly higher than other congeners. 88 250 1400 0 0.5 1 1.5 2 2.5 3 3.5 Corg (wt.%) A TCDD X PeCDD • HpCDD • OCDD Linear (OCDD) Linear (HpCDD) - Linear (PeCDD) • Linear (TCDD) Corg (wt.%)| • PeCDF A HxCDF X HpCDF X OCDF - Linear (HpCDF) - Linear (HxCDF) - Linear (PeCDF) - Linear (OCDF) Figure 27: B) Plot of dioxin and furan concentration vs. organic matter concentration with the >63 jum fraction removed. Note the increase in r value for HxCDD through OCDD dioxin and the decrease in r value for TCDD and PeCDD. 89 3.6. Discussion: The concentration of TOC and TN (0.5-1.7 wt.% TOC; 0.04-0.1 wt.% TN; Table 6) in the bulk sediment samples is typical for a paralic environment such as Howe Sound, and is similar to TOC and TN concentrations found to the north in the Squamish Delta sediments (Adams and Bustin, 2001). However, the range of TOC concentrations is smaller than values obtained in other cores of comparable length taken further south along Howe Sound (MacDonald et al, 1992). Unlike the cores taken by MacDonald et al (1992), the core sample taken in this study does not show a progressive decrease of TOC to a background concentration with increasing sediment depth (Figure 11a), as is often the case (Mayer, 1994). Reasons for this are unclear. Upon visual inspection, the core did not seem to be significantly affected by bioturbation, and this was confirmed during subsampling. The location of the core, chosen based upon its proximity to the Woodfibre Pulp Mill, could also be a contributing factor to the observed TOC profile. The area N receives not only sediments from the north, supplied from the distal reaches of the Squamish Delta, but also from the south. A return gyre affects this area, supplying sediments from other areas in the Sound (Syvitski et al, 1982). The proximity of the core to the Woodfibre Pulp Mill might result in a TOC signature that is directly linked to temporal changes in the discharge and composition of mill effluent. As a result, it is likely that a combination of these factors may be the cause of the irregular downcore changes in TOC concentration. This may also explain the ambiguity that arose from 210Pb dating, where multiple sediment sources could have disrupted the steady accumulation and decay of 210Pb from a single sediment source (Smith et al, 1980). The TOC and TN trends observed in the size fractionated sediments are identical (Figure 19a,b), with the > 63 pm fraction containing 55-70% of the TOC and 40-50% of the TN in each sample. The < 2 pm fraction contains 15-20% of the TOC and 25-30% of the TN in each sample, with the remainder being distributed between the three intermediate size fractions. The enrichment of TOC in the > 63 pm fraction is attributed to the presence of particulate rather than adsorbed OM on the surfaces of mineral grains, and is therefore independent of surface area (Adams and Bustin, 2001). However, the OM in the < 2 pm fraction, which probably represents approximately one fifth of the OM 90 present in the sample, is most likely adsorbed to mineral surfaces (Adams and Bustin, 2001) and represents the recalcitrant portion of the sample that is no longer susceptible to remineralization (Mayer, 1994). The Corg/N ratio trend for the bulk sediment samples shares a similar downcore profile as TOC (Figure 11a). C o r g/N values change from 13 to 23 over the length of the core (Figure 12), which suggests a dominant terrestrial source for the organic matter (Muller, 1977). However, minor scatter around the regression line in Figure 13 suggests the presence of either an additional type of OM, or a secondary source. Corg vs. TN relationship for the size fractionated sediments is also variable (Figure 20), particularly in the > 63 pm fraction, which appears to have consistently higher TOC than TN concentrations, as shown by the > 63 pm regression. This is similar to results from sediment samples collected from the Squamish Delta (Chapter 2), where the > 106 pm fraction falls on a more 'carbon rich' regression line. This is attributed to the dominance of particulate or 'detrital' OM over adsorbed OM in the coarsest fraction (Adams and Bustin, 2001). However, in this study, the > 63 pm fraction probably contains both detrital OM and some adsorbed OM due to the larger variation in grain size within this fraction. Linear regression of surface area and TOC for bulk sediment samples (Figure 17) explains 40% of the variance. Many studies have found significantly better correlation between these parameters, especially with samples collected from continental shelves (Bergamaschi et al, 1997; Mayer, 1994). Larger degrees of variation between surface area and TOC content is not uncommon in paralic settings (Adams and Bustin, 2001), and is attributed to variable proportions of detrital OM, and a much larger range of grain sizes in the bulk samples. The relationship between surface area and TOC in size fractionated samples highlights the effects of detrital OM and grain size on the correlation (Figure 21a,b). Figure 21a shows there is little relationship between surface area and TOC when all size fractions are considered, primarily due to the 4 samples from the > 63 pm, which have higher than expected TOC contents for their surface areas. These samples also have high surface area values (Table 8) when compared to intermediate size fractions, which may be the result of macroscopic mica flakes (probably muscovite) that were common in 91 this fraction. The remaining size fractions show a stronger relationship between surface area and TOC (r2 = 0.51; Figure 21b). However, three of the four < 2 pm fraction samples have lower than expected TOC contents than the regression predicts, a phenomenon not uncommon in paralic settings where TOC loadings are often lower than sediments of similar grain size from continental shelf regions (Keil et al, 1997, Mayer 1994). Excluding these outliers from Figure 21b further improves the regression, but is probably not representative of the actual relationship between TOC and surface area in the samples. Downcore concentration trends in polychlorinated organic pollutants show selective enrichment at specific horizons rather than gradual enrichment or depletion with increasing depth, as is usual with OM (Mayer, 1994). Thus, concentrations of total PCDD and PCDF are relatively constant except for the 10-25 cm interval and below 42 cm, where large increases in concentration occur (Figure 14a,b). Unfortunately, problems with 2I0Pb dating prevented derivation of a chronology for the core. Previously published data (MacDonald, 1992) from other parts of Howe Sound shows peak concentrations of 8 pg/g, 65 pg/g, and 30 pg/g (TCDF) and 660 pg/g, 480 pg/g and 340 pg/g circa 1970, 1982 and 1989 respectively, but without more accurate information on sedimentation and accumulation rates, and potential surface mixing within the sediments, it is impossible to correlate these dates with peak concentrations in the core. Bioturbation was observed in a similar core retrieved from the eastern arm of Howe Sound (MacDonald, 1992), suggesting that the sediments in the study core may have been mixed, but visual inspection upon retrieval and subsampling did not reveal evidence of bioturbation. It is also possible that any mixing that may have occurred resulted from the coring procedure and subsequent subsampling, although every effort was made to minimize disturbance during retrieval and processing. However, the complex sedimentary environment that was 210 the likely cause of the disrupted Pb results may also be the reason for the unusual response observed in the organochlorine compounds. This is likely, especially if the organochlorine compounds are related to surface area in the same manner as TOC. Without accurate temporal data it is not possible to relate current concentration levels of dioxins and furans with the initial concentrations in either effluent discharged from the Woodfibre Pulp Mill or atmospheric inputs from other sources. Thus, any change in 92 concentration from the time of initial input cannot be taken into account when assessing preservation of dioxins and furans and their relationship with surface area. Downcore trends in individual homologues (Figure 15; Figure 16) are very similar to those of PCDD and PCDF. In both the dioxin and furan families, hexachlorinated homologues are present in much higher concentrations than other homologues. When HxCDD is considered separately, a correlation between chlorination and increasing concentration is observed (Figure 15), suggesting that preservation potential may also be a function of the number of chlorine atoms present in the molecule. This phenomenon is not observed in furans (Figure 16), where the abundances of TCDF and OCDF are reversed, OCDF being the least concentrated of the five homologues, and TCDF being the most concentrated. There is evidence in the size fractionated sediment data to suggest that organochlorine compounds are selectively adsorbed to inorganic particle surfaces, and that their concentration in the < 2 urn fraction increases with depth. A commonality that exists in all four of the size fractionated samples is the high abundance of organochlorine compounds in the > 63 um fraction (Figure 22; Figure 23; Figure 24; Figure 25). This is attributed to the presence of particulate OM that is not adsorbed to particle surfaces. DF 14-16 shows depletion of both total and individual homologues in both dioxins and furans with progressively finer grain size, which strongly suggests that surface area adsorption is not the mechanism by which OM and organochlorine compounds are associated at this sediment depth (Figure 22). However, other homologues from sample DF 14-16 show an opposite trend, with increasing concentrations in finer size fractions. OCDD, HxCDF, HpCDF and OCDF all show minor enrichment in the < 2 urn fraction versus the 2-10 urn fraction (Figure 22a,b). Samples DF 20-22 and DF 34-36 show progressive enrichment from the 10-20 um through to the < 2 um fraction in total PCDD and PCDF, and in a number of individual homologues as well (Figure 23; Figure 24). This suggests an increasing association of organochlorine compounds with finer sediment fractions and thus increasing importance of surface area as the mechanism by which these compounds are preserved. This trend is more pronounced in sample DF 46-48, which shows increasing concentrations of total PCDD, HxCDD, HpCDD, OCDD, and all of the 93 furan homologues except for TCDF, from the 20-68 pm fraction to the < 2 pm fraction (Figure 25). The increase between the 2-10 pm and < 2 pm fractions is significantly greater than increases between coarser fractions, which highlights the significant increase in surface area in the < 2 pm fraction compared to coarser fractions. It is evident from Table 7 (Figure 14; Figure 15; Figure 16) that neither a downcore enrichment nor depletion trend exists for homologue or total homologue concentration in dioxins of furans. However, when concentrations are compared to surface areas, the highest concentrations, which are found in the 14-16 cm, 20-22 cm, 34-36 cm and 46-48 cm intervals, do correspond to the highest observed surface area values in three of the four intervals, which suggests some link between surface area and concentration. Correspondingly, depth intervals 4-5 cm, 24-26 cm and 40-42 cm which contain the lowest measured concentrations for the majority of the compounds analyzed also have the lowest surface area values. Although regression analyses of the concentration of organochlorine compounds and surface area in the bulk sediments yield r2 values as high as 0.54 (HxCDD; Figure 18), the nature of the correlation is somewhat misleading. The correlation is generated by the large concentration gap between the data point for the 46-48 cm depth interval and the other 9 data points in the 0-42 cm range. All of these samples have concentrations approximately 3-5 times lower than those in the 46-48 cm range and thus, tend to cluster on the left side of the plots in Figure 18. This distribution does not support the theory of a relationship between sediment surface area and dioxin/furan concentration. The spread of data points is slightly improved when the data from the 46-48 cm depth interval are removed, but this does not produce any significant change in the correlation coefficient between the two parameters. * 2 It is also clear from Figure 18 that a y-intercept value of approximately 4 m /g is common to all of the plots. Previous studies have found that the linear regression in a plot of OM concentration vs. surface area generally passes through the origin, indicating that as surface area increases, so does OM concentration, suggesting that the two parameters are intrinsically related (Mayer, 1994; Hedges et al, 1995; Bergamasch et al, 1997). The value of 4 m2/g may represent a threshold surface area that must be present before 94 chlorinated compounds will adsorb to sediment particle surfaces; however, it more likely reflects that fact that no samples were analyzed with surface area values of < 3 m /g. Removal of the 46-48 cm outlier does not significantly affect the y-intercept value. Relationships between homologue concentrations and surface area in size fractionated sediments are much stronger than those observed in the bulk sediment samples. Table 10 shows that correlation coefficients were significantly improved in most cases when the > 63 um fraction was omitted from the plots (Figure 26). As previously discussed, the > 63 pm fraction is dominated by particulate OM, in contrast to finer fractions where surface bound OM predominates. An overall increase in r value with depth (Table 10) supports results seen in Figure 26, which show that the relationship between surface area and concentration increases with depth for both dioxins and furans. Also observed in the case of the dioxins is an increase in r value with increasing chlorination, suggesting that homologues with more chlorine atoms in their molecular structure are more firmly bound on to particle surfaces. Table 10 shows that TCDD/F and PeCDD/F have the weakest relationship with surface area, showing little correlation at all until the 46-48 cm depth interval, where r2 values of 0.8 (PeCDD) and 0.9 (PeCDF) are achieved. Some of the plots show strong negative correlations between surface area and concentration, as is the case with TCDD in the 34-36 cm depth interval, which has a negative correlation coefficient of r = 0.98. The implication that some homologues are better preserved in coarse grained sediments (low surface area), whilst others are better preserved in fine grained sediments (high surface area) is misleading. It is more likely that homologues that show no correlation or a negative correlation with surface area are associated with non-adsorbed, particulate OM rather than surface bound OM, as is the case with TCDD and TCDF in all of the samples analyzed. The majority of the homologues from the 46-48 cm interval have a strong positive correlation with surface area (Table 10) with regression lines that pass through or close to the origin (Figure 26j). Good correlations with surface area are also observed in the 14-16 cm, 20-22 cm and 34-36 cm depth intervals; however, these plots generally have a significant negative y-intercept, which suggests that some of the chlorinated compounds 95 may be associated with OM not bound to particle surfaces as previously discussed. This conclusion is supported by the fact that almost every sample analyzed had highest concentrations in the > 63 pm fraction. The relationship between total PCDD/F concentration and surface area also improves with depth, going from 0.07 (14-16 cm) to 0.96 (46-48 cm) for PCDD and 0.11 (14-16 cm) to 0.9 (46-48 cm) for PCDF (Table 10). High homologue concentrations in the > 63 pm fraction are probably related to detrital rather than adsorbed OM, with some homologues preferentially absorbing in this fraction (Tetra-Pentachlorinated PCDD/F) as indicated by the data in Figure 27a,b. The r2 values increased for hexa- through octachlorinated dioxin/furan when the > 63 pm was removed (0.4/0.6 to 0.8 Dioxins, 0.4/0.7 to 0.8, Furans ; Figure 27b). Correspondingly, r2 values decreased in tetra- and pentachlorinated dioxin/furan when the > 63 pm was removed (0.6/0.3 to < 0.2, Dioxins, 0.7 to 0.6, Furans; Figure 27b). This suggests an intrinsic relationship between tetra- and pentachlorinated dioxin/furan and the > 63 pm fraction, whilst other homologues appear to be directly related to finer fractions. The improvement of the relationship between OM and homologue concentration in sediments < 63 pm (Figure 27b), as well as the strength of the relationship (r2 « 0.8, PCDD/F) suggests a strong link between OM and homologue concentrations. Similarities in downcore concentration profiles of dioxins and furans to that of TOC (Figure 11a; Figure 15; Figure 16) also support this conclusion. When placed in the context of surface area, which is a significant factor in controlling homologue preservation in sediments (Table 10; Figure 26), it appears likely that the relationship is somewhat symbiotic. The organochlorine compounds are likely 'attached' to the OM, which is in turn adsorbed to inorganic particle surfaces. The nature of the association between the organochlorine compounds and the OM is unclear. Particulate OM, however small, will have some surface area of its own, and therefore it is possible that the relationship is one of adsorption. It is also possible that the relationship is one of chemical bonding (absorption) of organochlorine compounds with OM prior to adsorption onto mineral surfaces. 96 The higher correlation between homologue concentration and surface area in fractionated sediments (which improves with increasing sediment depth; Table 10, Figure 26) could be the result of several factors. Significantly lower organochlorine emissions since 1990 may mean that concentrations are so low in the upper part of the core that dioxins and furans remain associated with particulate OM. Correspondingly, a drop in sedimentation rate, a change in sediment supply or a change in grain size distribution (the 4-5 cm sample had less mass in the fine fractions than the 24-26 cm and 40-42 cm samples; Figure 10) would lead to a shortage of mineral surfaces available for adsorption. A more likely hypothesis is that progressively more OM is broken down and remineralized over time, increasing the availability of chlorinated organic compounds for adsorption to inorganic sediment surfaces. Such a hypothesis is supported by the ubiquitous nature and low solubility of dioxins and furans. If this is the case, then a transition in association from particulate OM to adsorbed OM occurs with increasing sediment depth, and thus the relationship between homologue concentration and surface area should continue to improve with depth. Although sediment toxicity was not the focus of this study, it is interesting to note that the toxicity of bulk sediment samples ranges from 0.4 ng/kg TEQ to 20.6 ng/kg TEQ, with only four of the bulk samples analyzed exceeding the ISQG value of 0.85 ng/kg TEQ. These four samples were those selected for size fractionation: 14-16 cm, 20-22 cm, 34-36 cm and 46-48 cm. None of the TEQ values for these four samples exceeded the PEL value of 21.5 ng/kg TEQ. TEQ values for size fractionated samples fell above the ISQG value, but were usually less than the PEL value. However, several size fractions did exceed the PEL value, most notably in the 46-48 cm depth interval, where the > 63 urn fraction and < 2 um fraction had TEQ values of 67 and 40 respectively, suggesting significant contamination. 3.7. Conclusions: Analysis of bulk sediment samples taken from a core adjacent to the Woodfibre Pulp and Paper Mill (Figure 9) showed organic matter concentrations typical for a paralic environment (0.51-1.71 wt.%)! The average C o r g/N ratio of 15 suggests that the dominant 97 source of sedimentary organic matter is terrestrial. Further analyses revealed the presence of tetra- through octachlorinated dioxins (0.13-517.76 pg/g) and furans (0.4-129.25 pg/g), which were likely sourced directly from Woodfibre Pulp Mill via effluent discharge into Howe Sound. The primary source of organic and inorganic sediments for the Woodfibre area is the Squamish River, which discharges into the north end of Howe Sound via the Squamish Delta. However, complex currents in this area (Syvitski et al, 1982) often rework sediments, and can also transport sediments from secondary sources further south in the Sound. Other sources of organic and inorganic sediments include the Woodfibre Mill effluent, the barges that deliver unprocessed woodchips to the mill and material directly from the steep slopes surrounding the Sound. This complex sedimentary setting is the main causal factor in the unusual down core trends seen in TOC and TN concentration (Figure lla,b), C o r g/N ratio (Figure 12), chlorinated organic compound concentration (Figures 14-16), and the failure of 210Pb dating in producing a reliable chronology for the core. Surface area values for bulk sediments were typical of a paralic environment (2.43-11.96 m2/g), showing moderate correlation with organic carbon (Figure 17) and organochlorine pollutants (Figure 18), suggesting in turn that sediment surface area is a significant factor in the retention of both naturally occurring organic material and man-made organic pollutants in the sedimentary record. Results from the analysis of selected size fractionated samples showed significant enrichment of both TOC and industrial pollutants in the coarsest and finest sediment fractions (Figure 19; Figures 22-25) as well as moderate to strong linear correlations with sediment surface area (Figure 21; Figure 26). Organic matter and associated pollutants present in coarse grained sediments is likely particulate in nature and not adsorbed to particle surfaces. Over time, as the particulate material is broken down and remineralized, much of the organic matter and industrial pollutants will likely become adsorbed to particle surfaces. A strong relationship between OM and dioxin/furan concentration also occurs (Figure 27a,b) which supports the theory that pollutants adhere to OM prior to adsorption on to mineral surfaces. The nature of this 'bonding' is unclear and may either be chemical in nature, or may be in the form of a two step, absorption/adsorption process 98 related to the surface area of the OM itself. Some homologues (tetra- and pentachlorinated) are directly related to the coarsest sediment fraction (> 63 um), whilst other homologues (hexa- through octachlorinated) are concentrated in the finer sediment fractions (< 63 urn; Figure 27a,b). The strength of the relationship between surface area and dioxin and furan concentration is governed by two parameters, sediment depth and relative chlorination. Increasing sediment depth (core depth) produces stronger correlations between pollutant concentration and surface area; dioxin and furan compounds with higher numbers of chlorine atoms in their molecular structure e.g. hex-octachlorinated PCCD/F, appear to more susceptible to preservation through adsorption to sediment particle surfaces. The lack of variation observed in the geochemical composition and mineralogy of sediments in the upper reaches of Howe Sound (Adams and Bustin, 2001) indicates that the composition of the inorganic sediment fraction is not a factor in the adsorption of organic matter or pollutants on to particle surfaces (Thimsen et al, 1998) The 'adsorption budget' for dioxins/furans still remains unclear. What portion of the original input to the sedimentary system is adsorbed, versus how much is broken down before adsorption takes place, is important in determining the effectiveness of the adsorption mechanism in mediating industrial pollution of inland waterways and ocean waters. The fate of industrial pollutants in inland waterways and paralic environments has been the focus of intense scrutiny over the past two decades. The relationship between sediment surface area and pollutant concentration demonstrated in this study is intrinsically related to the relationship between OM and surface area (Mayer, 1994; Hedges et al, 1995). It is unlikely that this relationship is confined only to dioxins and furans, but is probably ubiquitous throughout many other industrial chemical classes such as PCBs, polychlorinated insecticides etc., as well as other types of pollutants such as heavy metals from the mining industry. 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(1998): Historical inputs of PCDDs, PCDFs, and PCBs to a British Columbia interior lake: The effect of environmental controls on pulp mill emissions. Environ. Sci. Technol. Vol. 32, pp. 331-337. Mayer,L.M. (1993): Organic matter at the sediment water interface. In Organic Geochemistry (ed. M. Engel and S.A. Macko) pp. 171-184, Plenum. Mayer, L.M. (1994): Surface area control of organic carbon accumulation in continental shelf sediments. Geochimica et Cosmochimica Acta, Vol. 58, No. 4, pp. 1271-1284. Mayer. L.M. (1999): Extent of coverage of mineral surfaces by organic matter in marine sediments. Geochimica et Cosmochimica Acta, Vol. 63, No. 2, pp. 207-215. McNee, J. (1997): The post-depositional cycling of Cd, Cu, Mo and Zn in several hydrographically distinct B.C. fjords. University of British Columbia, Department of Earth and Ocean Sciences, Ph.d. Thesis. Muller, P J. (1997): C/N ratios in Pacific deep-sea sediments; Effects of inorganic ammonium and organic nitrogen compounds sorbed by clays. Geochimica et Cosmochimica Acta, Vol. 41, pp. 765-776. Norwood, C. B., Hackett, M., Pruell, R. J., Butterworth, B. C , Williamson, K. J., Naumann, S. M. (1989): Polychlorinated dibenzo-p-dioxins and dibenzofurans in selected estuarine sediments. Chemosphere, Vol. 18, pp. 553-560. Oades, J.M. (1988): The retention of organic matter in soils. Biogeochem., Vol. 5, pp. 35-70. 103 Pearson, R. F., Swackhamer, D. L., Eisenreich, S. J., Long, D. T. (1998): Atmospheric inputs of polychlorinated Dibenzo-p-dioxins and Dibenzofurans to the Great Lakes: Compositional comparison of PCDD and PCDF in sediments. J. Great Lakes Res., Vol. 24, No. 1, pp. 65-82. Ransom, B., Bennett, R.J., Baerwald, R., Shea, K. (1997): TEM study of in situ organic matter on continental shelf margins: occurrence and the "monolayer" hypothesis. Mar. Geol. Vol. 138, pp. 1-9. Riggs, K. B., Brown, T. D., Schrock, M. E. (1995): PCDD/PCDF emissions from Coal-fired power plants. Organohalogen Compounds, Vol. 24, pp. 51-54. Rose, C. L., Rose, N. L., Harlock, S., Fernandes, A. (1997): An historical record of polychlorinated Dibenzo-p-dioxin (PCDD) and polychlorinated Dibenzofuran (PCDF) deposition to a remote lake in north west Scotland, U. K. The Science of the Total Environment, Vol. 198, pp. 161-173. Ruelle, P., Kesselring, U. W. (1997): Aqueous solubility prediction of environmentally important chemicals from the mobile order thermodynamics. Chemoshpere, Vol. 34, No. 2, pp. 275-298. Sanders, G., Jones, K. C, Hamilton-Taylor, J. (1992): Historical inputs of polychlorinated Biphenyls and other organochlorines to a dated lacustrine sediment core in rural England. Environ. Sci. Technol, Vol. 26, pp. 1815-1821. Sequi, P., Aringhieri, R. (1977): Destruction of organic matter by Hydrogen Peroxide in the presence of Pyrophosphate and its effect on soil specific surface area. SOIL SCI. SOC. AM. J., Vol. 41, pp. 340-342. Smith, J. N., Walton, A. (1980): Sediment accumulation rates and geochronologies measured in the Saguenay Fjord using the Pb-210 dating method. Geochimica et Cosmochimica Acta, Vol. 44, No. 2, pp. 225-240. Smith, J. N., Levy, E. M. (1990): Geochronology of polycyclic aromatic hydrocarbon contamination in sediments of the Saguenay Fjord. Environ. Sci. Technol, Vol. 24, pp. 874-879. Sparschu, G. 1., Dunn, F. L., Rowe, V. K. (1971): Study of Teratogenicity of 2, 3, 7, 8 - Tetrachlorodibenzo-p-dioxin in the rat. Food Cosmet. Toxicol, Vol. 9, pp. 405-412. Syvitski, J.P.M., MacDonald, R.D. (1982): Sediment character and provenance in a complex fjord; Howe Sound, British Columbia. CAN. J. EARTH. SCI. Vol. 19, pp. 1025-1044. 104 Thimsen, C.A., Keil, R.G. (1998): Potential interactions between sedimentary dissolved organic matter and mineral surfaces. Marine Chemistry, Vol. 62, pp. 65-76. Tiessen, H., Stewart, J.W., Hunt, H.W. (1984): Concepts of soil organic matter transformations in relation to organo-mineral particle size fractions. Plant and Soil, Vol. 76, pp. 287-295. Tyler, A. O., Millward, G. E., Jones, P. H , Turner, A. (1994): Polychlorinated Dibenzo-para-dioxins and Polychlorinated Dibenzofurans in sediments from U.K. Estuaries. Estuarine, Coastal and Shelf Science, Vol. 39, pp. 1-13. Verardo, D.J., Froelich, P.N., Mclntyre, A. (1990): Determination of organic carbon and nitrogen in marine sediments using the Carlo Erba NA-1500 Analyzer. Deep-Sea Research, Vol. 37, No. 1, pp. 157-165. 105 CHAPTER 4: CONCLUSIONS 4.1. Conclusions: ^\ Howe Sound, despite being partially restricted from open ocean waters, is a complex sedimentary environment. Sediments are derived from numerous sources, including the Squamish and Fraser Rivers (Syvitski et al, 1982), from mass wasting off steep valley sides, and from coastal industries such as mining and pulp and paper production. The dynamic nature of this environment, in contrast to the continental shelf and open ocean, has significant control on the distribution of OM in the sediments. Across the Squamish Delta, partitioning of sediments into facies that are related to delta hydrodynamics, affects TOC concentration and subsequently the relationship between TOC concentration and surface area. Beyond the distal reaches of the delta, complex current patterns and multiple sediment sources significantly affected the distribution of OM in a core retrieved adjacent to Woodfibre Pulp and Paper Mill. Despite abnormal downcore trends in OM and dioxin/furan concentrations, good correlation was observed between surface area and both TOC and organochlorine concentrations in bulk and size fractionated sediments. A relationship was also observed between dioxins and furans and OM that demonstrated that certain homologues are associated with OM, especially in coarse grained sediments. Surface area values for all of the samples analysed from the study area were on average lower than those found in other studies (Bergamaschi et al, 1997; Mayer, 1994). This difference is accounted for by the location of study area and the associated sedimentary conditions. Most of the sediment samples collected for this type of study originated from continental shelf areas which typically receive only fine-grained organic and inorganic sediments transported offshore by currents or by wind, or OM from primary production (Bergamaschi et al 1997; Mayer, 1994). These types of sedimentary environment can be considered as 'steady state' where fluctuations in sediment supply and accumulation rates are very small. This generates a sedimentary record where the temporal signature of many different chemical biomarkers, as well as physical sediment characteristics, can be examined. However, 'non-steady state' environments, such as 106 paralic environments, are very dynamic. With multiple sediment sources, seasonally driven changes in sediment supply and variable industrial inputs, significant fluctuation in sedimentation and accumulation rates can occur which may produce an erratic historical record. Physical reworking of sediments and/or bioturbation will further modify physical and biochemical signatures. The close proximity of this study area to its primary sediment supply, the Squamish River, produced a silt dominated grain size profile in which approximately two thirds of the total mass fell within the 2-50 pm class. The range of bulk surface area values measured was 0.6-2.9 m2/g in Squamish Delta sediments and 2.5-12 m2/g in down core samples; size fractionated surface area values ranged from 0.6-12.5 m2/g in deltaic sediments and 1.5-22 m2/g in down core samples. Despite relatively low surface areas compared to continental margin sediments, good correlations were found with OM in surface grab and core samples, as well as with organochlorine compounds that were likely sourced from the nearby Woodfibre Pulp and Paper Mill. It is evident, however, that a significant amount of OM in this paralic environment is present in particulate form (POM), both on macroscopic and microscopic scales, and thus is not related to surface area. It is clear that adsorption on to mineral grain surfaces is an important mechanism for preservation of OM in marine sediments, and that it has significant implications for the formation of petroleum source rocks (Adams and Bustin, 2001) and the preservation of industrial pollutants in the world's oceans. Numerous factors play a role in this important relationship, not only in terms of governing the surface area available for adsorption (i.e. mass distribution, grain morphology etc.), but also in the availability of OM for adsorption (i.e. sedimentation and accumulation rates, redox conditions, sediment source etc.; Calvert et al, 1996). As yet, no definitive answer exists on nature of the attachment of OM to mineral grain surfaces or its distribution relative to the available surface area (Hedges and Keil, 1995; Ransom, 1997). Of the two main theories that exist, monolayer or super-monolayer grain coatings of moderately sized organic molecules suggested by the proportionality between surface area and organic matter (Hedges and Keil, 1995; Mayer, 1994) or discrete 'pockets' of OM on grain surfaces (Mayer, 1999; Ransom, 1997), the latter has gained recent support. A more random distribution of 107 organic matter on grain surfaces supports the idea that certain areas of grain surfaces such as pits of crevices (mesopores; Mayer 1994) can protect OM from hydro lytic attack by enzymes. Kubicki et al (1997) has also suggested that OM is distributed unevenly on clay mineral surfaces, adsorbed primarily to the edge sites only. Mayer (1999) has recently suggested that based on new data that supports an uneven distribution of OM across grain surfaces, that the term 'monolayer' be dropped because it implies a condition that probably does not exist. The precise conditions required for adsorption to occur, or when, or how long it takes to bind the adsorbate to adsorbent in the sedimentary system are unclear. Changes in the character and strength of the relationship with increasing sediment depth (core depth) suggest that time is a critical factor, with more OM adsorbed as time goes by. However, many authors have shown that OM levels decrease to a 'refactory background concentration' that reflects only the most recalcitrant portion of the OM that is strongly resistant to biodegradation (Mayer, 1994). Data presented in this study suggests an intrinsic relationship between organochlorine compounds, specifically the dioxin and furan families and sediment surface area, albeit not as straight forward as the now well established relationship between surface area and OM (Hedges and Keil, 1995; Mayer, 1994). Sediment depth, grain size and molecular chlorination all appear to impact the preservation of both dioxins and furans in the sediments of the study area. Tyler et al (1994) also demonstrated a correlation between sediment surface area and PCDD/PCDF, suggesting that lipids can scavenge the organochlorine compounds prior to adsorption onto mineral grain surfaces. This 'two-stage' process is similar to that put forward in this study to explain the high levels of PCDD/Fs found in the coarse sediment fraction (> 63pm). Hites (1990) suggested that the scavenging potential of PCDD/Fs in the atmosphere is related to molecular chlorination; the higher the chlorination, the greater the chance of being scavenged and reaching the 'sedimentary sinks'. This supports the findings in this study that aside from HxCDD, dioxins with more chlorine atoms were present in greater concentrations than those with less chlorine atoms. This is important when considering sediment toxicity, as more chlorinated dioxins and furans are less toxic than the lesser chlorinated dioxins and furans such as TCDD. 108 The surface area of sediments has become 'generally' accepted as the dominant mechanism by which significant amounts of organic matter can be preserved in the worlds oceans and inland waterways, which makes it an important factor in the global carbon cycle. Hedges and Keil (1995) have suggested that only 1% of annual terrestrial productivity is discharged into the worlds oceans, and that organic matter preservation in deltaic environments accounts for 44% (70 x 1012 gC/yr) of TOC buried per year. It is thought that up to 90% of the total organic matter burial in oceans takes place in deltaic and continental margin sedimentary environments (Hedges and Keil, 1995), but considering that as much as 90% of preserved organic matter in the Earth's crust is present as kerogen in petroleum source and reservoir rocks, the actual amount of organic matter available for burial and preservation is very small. With this in mind, the mechanism of surface area adsorption of organic matter on to inorganic sediment surfaces becomes critical in determining how much organic matter is ultimately preserved in the marine environment, although many questions still remain as to the exact nature and mechanisms that control the adsorbate (Organic Matter) -adsorbent (Mineral Grain Surface) bond. 109 4.1. References: • Adams, R.S., Bustin, R. Marc (2001): The effects of surface area, grain size and mineralogy on organic matter sedimentation and preservation across the modern Squamish Delta, British Columbia; the potential role of sediment surface are in the formation of petroleum source rocks. International Journal of Coal Geology, V o l . 46, pp. 93-112. • Bergamaschi, B.A., Tsamakis, E., Keil, R.G., Eglinton, T.I., Montlucon, D.B., Hedges, J.I. (1997): The effect of grain size and surface area on organic matter, lignin and carbohydrate concentration, and molecular compositions in Peru Margin sediments. Geochimica et Cosmochimica Acta, Vol. 61, No. 6, pp. 1247-1260. • Calvert, S.E., Bustin, R.M., Ingall, E.D. (1996): Influence of water column anoxia and sediment supply on burial and preservation of organic carbon in marine shales. Geochimica et Cosmochimica Acta, Vol. 60, No. 9, pp. 1577-1593. • Hedges, J.L, Keil, R.G. (1995): Sedimentary organic matter preservation: an assessment and speculative synthesis. Mar. Chem. Vol. 49, pp. 81-115. • Hites, R. (1990): Environmental behaviour of chlorinated dioxins and furans. Acc. Chem. Res. Vol. 23, No. 6, pp. 194-201 • Kubicki, J. D., Itoh, M. J., Schroeter, L. M., Apitz, S. E. (1997): Bonding mechanisms of salicylic acid adsorbed on to illite clay: An ATR-FTIR and molecular orbit study. Env. Sci. Tech. V o l . 31, pp. 1151-1156. • Mayer, L.M. (1994): Surface area control of organic carbon accumulation in continental shelf sediments. Geochimica et Cosmochimica Acta, Vol. 58, No. 4, pp. 1271-1284. • Mayer. L.M. (1999): Extent of coverage of mineral surfaces by organic matter in marine sediments. Geochimica et Cosmochimica Acta, Vol. 63, No. 2, pp. 207-215. • Ransom, B., Bennett, R.J., Baerwald, R., Shea, K. (1997): TEM study of in situ organic matter on continental shelf margins: occurrence and the "monolayer" hypothesis. Mar. Geol. Vol. 138, pp. 1-9. • Syvitski, J.P.M., MacDonald, R.D. (1982): Sediment character and provenance in a complex fjord; Howe Sound, British Columbia. Can. J. Earth. Sci. Vol. 19, pp. 1025-1044. 110 Tyler, A.O., Millward, G. E., Jones, P. H., Turner, A. (1994): Polychlorinated Dibenzo-para-dioxins and Polychlorinated Dibenzofurans in sediments from U.K. estuaries: Estuarine, Coastal Shelf Science, Vol . 39 , pp. 1-13. I l l CHAPTER 5: APPENDICES 5.1 Appendix A: Major and Minor Element Concentration Data IS O H o o o o o o o o o o o o o o o o o o oo cN o 0 0 a * «j lO IT) r~ C N m in t-; O O —' —> 00 VO VO VO Ul C N —< 00 CN ON CN cn 06 in d 2 in vo vo °^ ON CN vo o >-i r-~ 1— CN vq O p r~; oq as ON CN d d 06 cn ^ 10 vo vo vo <n vo VD vo r~ vo CN 00 OO O CN ON O CN ON in vo vo in in O ^ ^ T T r - O N ^ O N O O O N V O r ^ c n ^ ^ i . ^ - ' . C N . ' — ' - ^ C N C N C N C N . o o o o o o o o o o o 0 0 d 0 d ° d d d d d d 0 O N O N O N T r o o i n v o o o N c n r ^ C N C N C N C N — C N ( N C N C N - H C N voooTrcNr~vO'd-^>n>nmoino\in>n oq CN r-; cn cq vq — ; P 1 0 ^ » i f l ^ ^ H . » o ' i o v d i / i i n i / i , T i n o 6 ^ i o ^ v i i o i / i ^ " ^HVO — ON CN CN cn t - .vqpvq>ncnvD^) -T t i n v d i n i n ^ ^ r i n o moocncn^HO'^-'^-'^rcN ooor~;ONvqcNoqr-;'nr-; CN CNCNCNCNCNCNCNCNCN ^ <N 00 h r. invomON — ON r-- m ON r— cncqONONoqo\--;pr~:oqoqinON CN C N ^ C N C N C N C N C M C N C N C N C N C N vor~cNr^co_ c N | i n r f > ^ r t M N m o \ v o a i ( N i i - i ' t r - ^ ' ' n T f c n i n c n ^ ^ ^ - * i n " o c N c N T f ^ ^ ! c N c n - ^ c N ^ f ^ ^ r c N - * c o ' . O O v q — • r-; ON 00 -H (\j ^vdvDinininininvd-^r vo —' r~ 00 —• CN ON ON ON CN p p vq r^' in vo vo vo TT' r - i ON ON in ON ON oq <N —• in in in in vd >n cn cn cn .—' •stoocncncNTfincNTf in r-- vo vo — ' H m N r- in cn CN o ^ - ^ - s t i n c N ^ v o o N c o r ^ r-~vocnTj-cNcncno>n'st i n i n i n i n i n i n i n i n i n i n m i n i n m i n i n i n i n i n m i n i n i n i n i n r~ t^- r~-O 00 ON ON >—1 m vo 00 CN O v o v o ^ v d v d ^ r - - ^ v d v D v d ^ r ^ w S v d v d v d t ^ v d i > - ^ , - H c N r ^vo— ' o o-vl-^H - . o o c n c n ^ O O N O O O N V O O O N —; ^ N ON " "" r~ vd r~ CN—' (S m « - CN^CNCNONCNO^ONcn-HCNONONCNcncN'- cn d d d d d d d d d d d d d d d d d d d d d d d d d a. & N ^ 1 t W * h 30 CM 1 0 • M m ^ i r j v O t ^ o o O N O ^ H f N c n ^ H r t H H H H H H N N N N t ^ N Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q w CM o OO OO CN so so m o o oo rt so t--IO * H r-~ r-~ so d o d OO OS CN t t • SO o d d 1^ CN CN . so ° d d in N o\ r> oo in o d d ON so r~ SO r- m o d d CN CN OO r-~ r- in o d d o cn n ^ e CN . O <^> so O in so so -3- oo o cn so OO rt O in so so >-i r~ ON cn in TI->n O <N m so so in O <-> in so so Ol Ol Ol 00 —< cn r-! rt m so so ^ in ^ m 1 0 so m rt Os ^ f - rt MS m so CN o) in rt 00 in r-^ rt rt in so so in o OH so cn os cN cn rt r-~ cn 00 CN cn rt 00 00 m CN cn CN rt 00 in m cn CN 00 in in CN cn CN o d d ON ON o~ CN cn CN o d d ! S OO s t cn m CN o d d rt r— cn cn m CN o d d Ol — so in ON so os in CN so 01 CN cn 00 00 so in OO ON OO cn t- in TI- m so ON cn m rt j^-<N O Tf « cn cs ® so so r -00 Tr Tr c i cs cs CN rt rt OJ Tr Ol cn oi oi t> CN TT cn in sq cn oi oi T1- cn r-~ TJ- so sq cn oi oi in cn r-rt in >n cn oi oi CN so t— TI- Tfp in cn oi oi so cn TT 10 sq cn oi oi 00 cn TI-01 in 00 cn oi oi a u cu N in I rt cN TT CN CN in cn 00 O rt oi t in 00 0 oi oi o\ m os o 01 r- cn 00 o o 00 . Tl" 00 CN 00 O t^-. 4) SO OO SO rt 00 ON so in Tf Ol rt so cn rt so so so ^ r" in cn 00 cn ol OS rt —- in ON > so ui •ct fN (S cn o 00 r- r~ cn ON sq in so so in SO TI; so so in ON r~ 01 cn cn in so so in Tf ON O so u B 3 Xl < S E 3 S-o CN rt ol sq cn o r^' so in — ol cn C N 1 0 Tr' so in m m ON 00 r> 00 Nt so TI- so in m — r— ON in r-; TT' so in oi so so 00 00 oi Tf' so so ON Ol rt SO SO OO •t SO IO r—- SO ON 00 SO Tr' so in ON ON 00 00 SO Ol r-~. sq Tf r> so \d so 00 st cn cn in r> so so ON Ol Tf TT in in > so so rt Ol Tf O rt SO r> in so 00 in so TT in so r> so so cn ON — 1/1 p> 00 r> so so cn ol cn cn _ cn m CN O O O O O O O O O O O O O O O O O O O O a. E . w cn a3§ 3 * V •o CN 1 CN 1 ~"< v 3 £ 3 § v 3 s in £ so in Q cn Q cn Q cn Q cn Q cn Q cn Q cn CN Q cn 114 c I Pb (ppm) 12.7 7.3 11.6 9.2 6.8 6.1 7.3 8.2 10.3 6.9 3.6 6.7 4.8 12 4.5 5.6 12.3 8.9 7 6.3 9.8 8.4 8.4 6.2 7.6 Ba (ppm) | 622.8 634.7 657.8 649.6 649.6 623.1 635.4 580.3 587.2 632.5 534.5 560.2 625.1 611.8 582.5 567.4 606.4 664.5 624 628.5 659.9 611.3 627.1 604.8 676.4 Zr(ppm) | 106.6 119.3 110 112.6 128.2 106.5 111 125.8 123.5 130.4 70.8 120.5 103.6 112.3 85.8 128.3 125.7 118 92.6 89.8 114.6 111.8 113.6 108.5 113.1 t Y(ppm) | 1 Sr(ppm) | 640.1 666.2 641 651.4 650.7 704.1 649.4 661.8 641.2 648.3 703.1 652.9 679 626.1 704.3 649.4 638 635.3 694.6 692.3 642.9 629.3 631.6 680 637.7 | Rb (ppm) | 36.7 33.2 35.6 35.4 27.1 21.4 29.1 31.8 35.7 32.5 19.3 30 23 35.3 19.8 32.6 31 33.7 25.3 20.9 35.8 36 34.4 27.3 34.5 | As (ppm) | ^ t N i n s t T r t N i ^ ^ s q s q i n c N t N L n r - i n t N L o ^ ' t ^ i N f i ^ T f s t M T f n m n t ^ ^ ^ sd c i | Zn (ppm) 97.8 88.9 99.6 89.6 66.2 51 70.6 82.5 88 82.4 41.3 75.6 58 85.2 45.1 78.9 80.5 88.6 59.3 49 88.2 81.2 88.7 68.6 88 Cu (ppm) | 60.7 46 54.5 46.1 29.2 20 33.2 41.8 41.8 42 15.9 38.1 24 52.5 14.9 39.8 40.8 49.4 24.1 17.6 49 44.2 44.6 33.2 50.3 | Ni (ppm) | 24.6 24.6 26.1 24.6 21.8 21 22.7 24.2 23.6 25.9 17.3 23 21.5 24.3 18 25.1 21.8 23.5 20.9 16.4 25.4 25.8 24.5 22.9 24 | Co (ppm) | 15.1 15.9 16 15 14.5 11 13.8 14.9 16.3 14.6 9.6 16.6 11.5 15.5 9.9 13 16.7 17.8 14.4 12.4 15.5 12.4 15.4 15.1 15.5 | Mn (ppm) | 920.9 890.4 923.8 937 939.9 783 897 841.9 814.6 900.1 605.7 855.6 822.6 851.4 627.7 857.8 883 912.4 806.9 717.1 916.1 862.6 846 843.3 953.5 | Cr (ppm) | 45.9 44 42.6 46.3 75.4 101 62.5 49.3 40.9 63.7 154 59.3 84.9 48.4 88.7 57.2 54.8 61.4 115.8 91.9 103.2 50.1 45.2 59 61 ? a > 149.5 147.2 152.9 154.5 151.7 124 147.4 139.9 134.7 149.7 90 143 132.7 146.2 101.3 138.3 144.8 151.6 133.6 116.7 149.5 147 136.4 140.2 157.7 Sample # | H N n » m » r - » o \ H r t H r t r t H r t r t H H N N N N N N ^ o\ \o ^ so SO \o O) ao r> in ^ ^ Tt Tt ca ca Ifi r~ vq m t^ in CN oo* <—* '—* in* ^ d v c o o i n ^ r ^ c n t ^ o s o o v q r - ; a m ( N O \ v q c n ' ^ ^ r n O N m o o m d o d r n d ^ i d - - ^ |2 a m o o o v o o r t N ' * i f i i n ' v d ^ ^ i n ' i n ' c i r ^ i n r ^ r ^ i n r ~ r - ~ > n • ~ T t ON r> VD oo >n CN ON ^ ON CN oq cN oq ^•vr'f^dONIcioNrn'r^VD vo CN co ON r— OCNONCNCNt-^ o o m o r ^ i n i n t ~ i n v D oo CO IN CO CN VO in >n r-" CO ON vd vd oo oo VO OO vo 00 CN ON oo CN CO vd d 00 m CN '—i r» oo v : d S » oo m oo t-~ in* O O ^ O N O O ^ ^ O N ^ O N O O X ; v q o q o q O N r - ^ o q c o m v o r ^ r ^ — < C N O N O N vdcNCO*t~~dco*oo'co CN ON in co ON m oo rfrHNrHrHMrHHMH CN ^ —< CN ^ a, a.! C N O N O N O N ^ t C N C O O N cNodco'f-'o't-'vdd r -~ ' - 'vor— cNooONr-H i n r ^ v o i n r ^ v o i n r - ^ cN^i^in^cNcNON>nvqinvq--^i^^cN v d i n ' v d t f i N ^ ^ i n V v d o o V ^ i n ' m r -r~oo^oocNONr~oor-~ooocNON^^vD v o m r ~ v o v D v o o i n v o o v o r ^ v o v o r - ~ v o i i n c o v q v q i n c o i n ^ p ' o o d o v O v M r i f -v o - t v o v o ^ u i r - ' * in CN co co —< CO "^f vd CN m t-» m r ^ O N N T r ^ r N v q i n v D ^ ^ ; d v d v d d i r i v o ' ^ r - i ^ d v o ' o d r ^ - ^ - i n r ^ T t ^ r ~ - ^ r i n r - ~ ^ t - i n I* I' Q C/3 CN i ^ v 3 s Q cc CS| V "n CN Q C/3 V l o CN Q C/3 !0 £ CN V cQ ^ C N L , - , Q CN i1 V lO CN CN Q CN i ~-i V £ ^ CN u - , CN Q 116 Appendix B: PCDD/F Concentration Data Sample Site Howe Sound Sample # 0-1 cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 8.4 Congener Concentration (pg/g) DL TEQ Homologue Concentration (pg/g) DL 2,3,7,8-TCDD N D 0.06 0.00E+00 T C D D 3.13 0.06 1,2,3,7,8-PeCDD 0.15 0.08 1.50E-01 P e C D D 3.64 0.06 1,2,3,4,7,8-HxCDD 0.17 0.1 1.68E-02 H x C D D 15.78 0.1 1,2,3,6,7,8-HxCDD 1.68 0.1 1.68E-01 H p C D D 7.29 0.12 1,2,3,7,8,9-HxCDD 0.89 0.1 8.90E-02 O C D D 11.76 0.14 1,2,3,4,6,7,8-HpCDD 3.21 0.12 3.21E-02 O C D D 11.76 0.14 1.18E-03 Total P C D D 41.8 2,3,7,8-TCDF 0.97 0.05 9.70E-02 T C D F 3.72 0.05 1,2,3,7,8-PeCDF 0.11 0.06 5.50E-03 P e C D F 1.48 0.06 2,3,4,7,8-PeCDF 0.15 0.06 7.27E-02 H x C D F 1.44 0.08 1,2,3,4,7,8-HxCDF 0.15 0.08 1.50E-02 H p C D F 2.32 0.1 1,2,3,6,7,8-HxCDF ND 0.08 0.00E+00 O C D F 1 0.12 2,3,4,6,7,8-HxCDF 0.1 0.08 1.00-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.96 0.1 9.61 E-03 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 1 0.12 1.00E-04 Total T E Q 6.67E-01 Total P C D F 9.96 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1013 49 1,2,3,7,8-PeCDD 1002 97 1,2,3,6,7,8-HxCDD 1009 58 1,2,3,4,6,7,8-HpCDD 1009 68 O C D D 2025 57 2,3,7,8-TCDF 1015 43 1,2,3,7,8-PeCDF 1012 66 1,2,3,4,7,8-HxCDF 1013 62 1,2,3,4,6,7,8-HpCDF 1013 62 N D = Not Detected NDR = Concentrations are Included in Total T E Q 118 Sample Site Howe Sound Sample # 0-1 cm Rep. Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 8.4 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD N D 0.06 0.00E+00 T C D D 0.71 0.06 1,2,3,7,8-PeCDD 0.09 0.08 9.25E-02 P e C D D 1.09 0.06 1,2,3,4,7,8-HxCDD ND 0.1 0.00E+00 H x C D D 9.65 0.1 1,2,3,6,7,8-HxCDD 1.31 0.1 1.31E-01 H p C D D 5.42 0.12 1,2,3,7,8,9-HxCDD 0.62 0.1 6.20E-02 O C D D 10.19 0.14 1,2,3,4,6,7,8-HpCDD 2.25 0.12 2.25E-02 O C D D 10.19 0.14 1.02E-03 Total P C D D 27.06 2,3,7,8-TCDF 0.58 0.05 5.80E-02 T C D F 1.88 0.05 1,2,3,7,8-PeCDF 0.06 0.06 3.18E-03 P e C D F 0.67 0.06 2,3,4,7,8-PeCDF 0.06 0.06 3.00E-02 H x C D F 0.89 0.08 1,2,3,4,7,8-HxCDF 0.06 0.08 8.00E-03 H p C D F 1.89 0.1 1,2,3,6,7,8-HxCDF N D 0.08 0.00E+00 O C D F 0.79 0.12 2,3,4,6,7,8-HxCDF N D 0.08 0.00E+00 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.82 0.1 8.20E-03 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 0.79 0.12 7.91E-05 Total T E Q 4.16E-01 Total P C D F 6.12 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1007 48 1,2,3,7,8-PeCDD 1003 107 1,2,3,6,7,8-HxCDD 1014 67 1,2,3,4,6,7,8-HpCDD 1007 80 O C D D 2001 66 2,3,7,8-TCDF 1005 43 1,2,3,7,8-PeCDF 1010 100 1,2,3,4,7,8-HxCDF 1004 74 1,2,3,4,6,7,8-HpCDF 1010 72 ND = Not Detected NDR = Concentrations are Included in Total T E Q 119 Sample Site Howe Sound Sample # 4-5cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.1 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD N D 0.06 0.00E+00 T C D D 0.45 0.06 1,2,3,7,8-PeCDD 0.08 0.08 8.30E-02 P e C D D 0.91 0.06 1,2,3,4,7,8-HxCDD N D 0.1 0.00E+00 H x C D D 7.51 0.1 1,2,3,6,7,8-HxCDD 1.07 0.1 1.07E-01 H p C D D 5.13 0.12 1,2,3,7,8,9-HxCDD 0.56 0.1 5.60E-02 O C D D 8.69 0.14 1,2,3,4,6,7,8-HpCDD 2.61 0.12 2.61E-02 O C D D 8.69 0.14 8.69E-04 Total P C D D 22.69 2,3,7,8-TCDF 0.43 0.05 4.30E-02 T C D F 1.04 0.05 1,2,3,7,8-PeCDF ND 0.06 0.00E+00 P e C D F 0.74 0.06 2,3,4,7,8-PeCDF 0.06 0.06 2.88E-02 H x C D F 2.57 0.08 1,2,3,4,7,8-HxCDF 0.11 0.08 1.10E-02 H p C D F 4.93 0.1 1,2,3,6,7,8-HxCDF N D 0.08 0.00E+00 O C D F 1.5 • • 0.12 2,3,4,6,7,8-HxCDF 0.08 0.08 7.67E-03 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.75 0.1 1.75E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 1.5 0.12 1.50E-04 Total T E Q 3.81E-01 Total P C D F 13.78 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1010 58 1,2,3,7,8-PeCDD 1008 104 1,2,3,6,7,8-HxCDD 1014 62 1,2,3,4,6,7,8-HpCDD 1010 73 O C D D 2001 62 2,3,7,8-TCDF 1014 53 1,2,3,7,8-PeCDF 1006 98 1,2,3,4,7,8-HxCDF 1000 69 1,2,3,4,6,7,8-HpCDF 1005 68 ND = Not Detected NDR = Concentrations are Included in Total TEQ 120 Sample Site Howe Sound Sample # 9-10cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.00 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD ND 0.06 0.00E+00 T C D D 1.47 0.06 1,2,3,7,8-PeCDD 0.16 0.08 1.60E-01 P e C D D 2.52 0.06 1,2,3,4,7,8-HxCDD 0.13 0.1 1.30E-02 H x C D D 17.68 0.1 1,2,3,6,7,8-HxCDD 2.19 0.1 2.19E-01 H p C D D 9.58 0.12 1,2,3,7,8,9-HxCDD 1.06 0.1 1.06E-01 O C D D 16.39 0.14 1,2,3,4,6,7,8-HpCDD 3.93 0.12 3.93E-02 O C D D 16.39 0.14 1.64E-03 Total P C D D 47.64 2,3,7,8-TCDF 1.01 0.05 1.01E-01 T C D F 3.56 0.05 1,2,3,7,8-PeCDF 0.1 0.06 5.18E-03 P e C D F 1.37 0.06 2,3,4,7,8-PeCDF 0.13 0.06 6.73E-02 H x C D F 1.85 0.08 1,2,3,4,7,8-HxCDF 0.14 0.08 1.40E-02 H p C D F 3.3 0.1 1,2,3,6,7,8-HxCDF 0.1 0.08 1.02E-02 O C D F 1.55 0.12 2,3,4,6,7,8-HxCDF 0.09 0.08 9.00E-03 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.41 0.1 1.41 E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 1.55 0.12 1.55E-04 Total T E Q 7.60E-01 Total P C D F 11.63 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1007 46 1,2,3,7,8-PeCDD 1007 89 1,2,3,6,7,8-HxCDD 1011 55 1,2,3,4,6,7,8-HpCDD 1003 65 O C D D 2005 52 2,3,7,8-TCDF 1000 41 1,2,3,7,8-PeCDF 1003 85 1,2,3,4,7,8-HxCDF 1004 60 1,2,3,4,6,7,8-HpCDF 1004 58 ND = Not Detected NDR = Concentrations are Included in Total TEQ 121 Sample Site Howe Sound Sample # 14-15cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.7 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.23 0.06 2.30E-01 T C D D 16.86 0.06 1,2,3,7,8-PeCDD 0.71 0.08 7.06E-01 P e C D D 24.05 0.06 1,2,3,4,7,8-HxCDD 0.55 0.1 5.48E-02 H x C D D 108.35 0.1 1,2,3,6,7,8-HxCDD 10.72 0.1 1.07E+00 H p C D D 24.68 0.12 1,2,3,7,8,9-HxCDD 5.05 0.1 5.05E-01 O C D D 26.34 0.14 1,2,3,4,6,7,8-HpCDD 10.8 0.12 1.08E-01 O C D D 26.34 0.14 2.93E-03 Total P C D D 200.28 2,3,7,8-TCDF 7.21 0.05 7.21E-01 T C D F 23.5 0.05 1,2,3,7,8-PeCDF 0.49 0.06 2.43E-02 P e C D F 5.51 0.06 2,3,4,7,8-PeCDF 0.57 0.06 2.87E-01 H x C D F 3.23 0.08 1,2,3,4,7,8-HxCDF 0.28 0.08 2.08E-02 H p C D F 3.95 0.1 1,2,3,6,7,8-HxCDF ND 0.08 0.00E+00 O C D F 1.55 0.12 2,3,4,6,7,8-HxCDF 0.27 0.08 2.88E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.89 0.1 1.89E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 1.55 0.12 1.55E-04 Total T E Q 3.78E+00 Total P C D F 37.74 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1001 51 1,2,3,7,8-PeCDD 1011 83 1,2,3,6,7,8-HxCDD 1000 49 1,2,3,4,6,7,8-HpCDD 998 47 O C D D 1985 28 2,3,7,8-TCDF 1012 46 1,2,3,7,8-PeCDF 1000 77 1,2,3,4,7,8-HxCDF 1014 51 1,2,3,4,6,7,8-HpCDF 1011 48 ND = Not Detected NDR = Concentrations are Included in Total T E Q 122 Sample Site Howe Sound Sample # 20-22cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.8 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.16 0.06 1.60E-01 T C D D 1.52 0.06 1,2,3,7,8-PeCDD 0.46 0.08 4.60E-01 PeCDD 3.89 0.06 1,2,3,4,7,8-HxCDD 0.13 0.1 1.30E-02 H x C D D 66.75 0.1 1,2,3,6,7,8-HxCDD 7.89 0.1 7.89E-01 H p C D D 14.11 0.12 1,2,3,7,8,9-HxCDD 4.17 0.1 4.17E-01 O C D D 19.52 0.14 1,2,3,4,6,7,8-HpCDD 5.36 0.12 5.36E-02 O C D D 19.52 0.14 1.95E-03 Total P C D D 105.79 2,3,7,8-TCDF 4.66 0.05 4.66E-01 T C D F 14.19 0.05 1,2,3,7,8-PeCDF 0.22 0.06 1.10E-02 PeCDF 2.46 0.06 2,3,4,7,8-PeCDF 0.29 0.06 1.46E-01 H x C D F 2.42 0.08 1,2,3,4,7,8-HxCDF 0.15 0.08 1.50E-02 H p C D F 4.45 0.1 1,2,3,6,7,8-HxCDF 0.11 0.08 1.07E-02 O C D F 1.87 0.12 2,3,4,6,7,8-HxCDF 0.1 0.08 1.00E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.97 0.1 1.97E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 1.78 0.12 1.78E-04 Total T E Q 2.57E+00 Total P C D F 25.3 Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 997 49 1,2,3,7,8-PeCDD 1007 96 1,2,3,6,7,8-HxCDD 1012 62 1,2,3,4,6,7,8-HpCDD 1004 75 O C D D 2001 66 2,3,7,8-TCDF 996 43 1,2,3,7,8-PeCDF 1006 91 1,2,3,4,7,8-HxCDF 1012 70 1,2,3,4,6,7,8-HpCDF 1010 67 ND = Not Detected NDR = Concentrations are Included in Total TEQ 123 Sample Site Howe Sound Sample # 24-26cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.9 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.06 0.06 6.00E-02 T C D D 0.4 0.06 1,2,3,7,8-PeCDD 0.09 0.08 9.00E-02 PeCDD 0.87 0.06 1,2,3,4,7,8-HxCDD N D 0.1 0.00E+00 H x C D D 10.96 0.1 1,2,3,6,7,8-HxCDD 1.51 0.1 1.51E-01 H p C D D 4.4 0.12 1,2,3,7,8,9-HxCDD 0.73 0.1 7.30E-02 O C D D 7.46 0.14 1,2,3,4,6,7,8-HpCDD 2.08 0.12 2.08E-02 O C D D 7.46 0.14 7.48E-04 Total P C D D 24.09 2,3,7,8-TCDF 1.3 0.05 1.30E-01 T C D F 3.74 0.05 1,2,3,7,8-PeCDF 0.08 0.06 3.95E-03 P e C D F 0.73 0.06 2,3,4,7,8-PeCDF NDR(O.l) 0.06 5.00E-02 H x C D F 0.91 0.08 1,2,3,4,7,8-HxCDF 0.1 0.08 1.00E-02 H p C D F 2.23 0.1 1,2,3,6,7,8-HxCDF N D 0.08 0.00E+00 O C D F 1.27 0.12 2,3,4,6,7,8-HxCDF N D 0.08 0.00E+00 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.81 0.1 8.06E-03 1,2,3,4,7,8,9-HpCDF ND 0.1 0.00E+00 O C D F 1.27 0.12 1.27E-04 Total T E Q 5.98E-01 Total P C D F 8.88 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1016 47 1,2,3,7,8-PeCDD 1008 84 1,2,3,6,7,8-HxCDD 1002 52 1,2,3,4,6,7,8-HpCDD 1002 61 O C D D 2002 52 2,3,7,8-TCDF 1006 42 1,2,3,7,8-PeCDF 1006 76 1,2,3,4,7,8-HxCDF 1006 55 1,2,3,4,6,7,8-HpCDF 1003 55 ND = Not Detected NDR = Concentrations are Included in Total TEQ 124 Sample Site Howe Sound Sample # 30-32cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.00 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD ND 0.06 0.00E+00 T C D D 0.13 0.06 1,2,3,7,8-PeCDD 0.09 0.08 9.00E-02 P e C D D 1.47 0.06 1,2,3,4,7,8-HxCDD 0.13 0.1 1.30E-02 H x C D D 14.06 0.1 1,2,3,6,7,8-HxCDD 1.47 0.1 1.47E-01 H p C D D 6.32 0.12 1,2,3,7,8,9-HxCDD 0.84 0.1 8.40E-02 O C D D 8.23 0.14 1,2,3,4,6,7,8-HpCDD 3.31 0.12 3.31E-02 O C D D 8.23 0.14 8.23E-04 Total P C D D 30.21 2,3,7,8-TCDF 0.88 0.05 8.80E-02 T C D F 2.27 0.05 1,2,3,7,8-PeCDF 0.12 0.06 6.02E-03 P e C D F 0.89 0.06 2,3,4,7,8-PeCDF 0.11 0.06 5.50E-02 H x C D F 0.98 0.08 1,2,3,4,7,8-HxCDF 0.2 0.08 2.00E-02 H p C D F 1.26 0.1 1,2,3,6,7,8-HxCDF 0.13 0.08 1.25E-02 O C D F 0.46 0.12 2,3,4,6,7,8-HxCDF ND 0.08 0.00E+00 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.72 0.1 7.16E-03 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 0.46 0.12 4.60E-05 Total T E Q 5.57E-01 Total P C D F 5.86 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 999 44 1,2,3,7,8-PeCDD 1008 93 1,2,3,6,7,8-HxCDD 1011 63 1,2,3,4,6,7,8-HpCDD 1003 72 O C D D 1999 58 2,3,7,8-TCDF 1001 40 1,2,3,7,8-PeCDF 1006 90 1,2,3,4,7,8-HxCDF 1009 71 1,2,3,4,6,7,8-HpCDF 1007 67 ND = Not Detected NDR = Concentrations are Included in Total TEQ 125 Sample Site Howe Sound Sample # 34-36cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.1 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.06 0.06 6.00E-02 T C D D 0.64 0.06 1,2,3,7,8-PeCDD 0.19 0.08 1.90E-01 P e C D D 2.27 0.06 1,2,3,4,7,8-HxCDD 0.2 0.1 2.00E-02 H x C D D 32.4 0.1 1,2,3,6,7,8-HxCDD 4.03 0.1 4.03E-01 H p C D D 9.56 0.12 1,2,3,7,8,9-HxCDD 2.01 0.1 2.01E-01 O C D D 13.45 0.14 1,2,3,4,6,7,8-HpCDD 4.82 0.12 4.82E-02 O C D D 13.45 0.14 1.35E-03 Total P C D D 58.32 2,3,7,8-TCDF 2.17 0.05 2.17E-01 T C D F 6.69 0.05 1,2,3,7,8-PeCDF 0.2 0.06 1.00E-02 P e C D F 1.74 0.06 2,3,4,7,8-PeCDF 0.2 0.06 1.00E-01 H x C D F 1.88 0.08 1,2,3,4,7,8-HxCDF 0.27 0.08 2.70E-02 H p C D F 2.44 0.1 1,2,3,6,7,8-HxCDF 0.18 0.08 1.81 E-02 O C D F 1.1 0.12 2,3,4,6,7,8-HxCDF 0.19 0.08 1.85E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.23 0.1 1.23E-02 1,2,3,4,7,8,9-HpCDF 0.13 0.1 1.30E-03 O C D F 1.1 0.12 1.10E-04 Total T E Q 1.33E+00 Total P C D F 13.85 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1006 51 1,2,3,7,8-PeCDD 1005 98 1,2,3,6,7,8-HxCDD 1009 64 1,2,3,4,6,7,8-HpCDD 1011 74 O C D D 2012 63 2,3,7,8-TCDF 999 45 1,2,3,7,8-PeCDF 1004 93 1,2,3,4,7,8-HxCDF 1005 69 1,2,3,4,6,7,8-HpCDF 1012 67 ND = Not Detected NDR = Concentrations are Included in Total TEQ 126 Sample Site Howe Sound Sample # 40-42cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.00 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD N D 0.06 0.00E+00 T C D D 0.13 0.06 1,2,3,7,8-PeCDD 0.11 0.08 1.10E-01 P e C D D 0.45 0.06 1,2,3,4,7,8-HxCDD ND 0.1 0.00E+00 H x C D D 14.58 0.1 1,2,3,6,7,8-HxCDD 2.27 0.1 2.27E-01 H p C D D 4.54 0.12 1,2,3,7,8,9-HxCDD 0.88 0.1 8.80E-02 O C D D 7.31 0.14 1,2,3,4,6,7,8-HpCDD 2.15 0.12 2.15E-02 O C D D 7.31 0.14 7.31E-04 Total P C D D 27.01 2,3,7,8-TCDF 1.54 0.05 1.54E-01 T C D F 3.42 0.05 1,2,3,7,8-PeCDF 0.07 0.06 3.50E-03 P e C D F 0.4 0.06 2,3,4,7,8-PeCDF N D 0.06 0.00E+00 H x C D F 0.65 0.08 1,2,3,4,7,8-HxCDF N D 0.08 0.00E+00 H p C D F 1.44 0.1 1,2,3,6,7,8-HxCDF N D 0.08 0.00E+00 O C D F 0.49 0.12 2,3,4,6,7,8-HxCDF N D 0.08 0.00E+00 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.67 0.1 6.68E-03 1,2,3,4,7,8,9-HpCDF ND 0.1 0.00E+00 O C D F 0.49 0.12 4.90E-05 Total T E Q 6.11E-01 Total P C D F 6.4 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1016 38 1,2,3,7,8-PeCDD 1012 68 1,2,3,6,7,8-HxCDD 1006 46 1,2,3,4,6,7,8-HpCDD 1011 53 O C D D 2011 44 2,3,7,8-TCDF 1014 35 1,2,3,7,8-PeCDF 1007 66 1,2,3,4,7,8-HxCDF 1011 50 1,2,3,4,6,7,8-HpCDF 1012 49 ND = Not Detected NDR = Concentrations are Included in Total TEQ 127 Sample Site Howe Sound Sample # 46-48cm Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.00 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 1.46 0.06 1.46E+00 T C D D 6.88 0.06 1,2,3,7,8-PeCDD 2.82 0.08 2.82E+00 PeCDD 22.3 0.06 1,2,3,4,7,8-HxCDD 0.54 0.1 5.40E-02 H x C D D 517.76 0.1 1,2,3,6,7,8-HxCDD 72.09 0.1 7.21E+00 H p C D D 62.71 0.12 1,2,3,7,8,9-HxCDD 25.29 0.1 '2.53E+00 O C D D 87.95 0.14 1,2,3,4,6,7,8-HpCDD 31.45 0.12 3.14E-01 O C D D 87.95 0.14 8.79E-03 Total P C D D 697.6 2,3,7,8-TCDF 48.66 0.05 4.87E+00 T C D F 129.25 0.05 1,2,3,7,8-PeCDF 1.56 0.06 7.80E-02 PeCDF 13.75 0.06 2,3,4,7,8-PeCDF 2.02 0.06 1.01E+00 H x C D F 13.8 0.08 1,2,3,4,7,8-HxCDF 0.66 0.08 6.60E-02 H p C D F 23.33 0.1 1,2,3,6,7,8-HxCDF 0.41 0.08 4.11 E-02 O C D F 8.58 0.12 2,3,4,6,7,8-HxCDF 0.4 0.08 3.96E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 9.13 0.1 9.13E-02 1,2,3,4,7,8,9-HpCDF 0.42 0.1 4.16E-03 O C D F 8.58 0.12 8.58E-04 Total T E Q 2.06E+01 Total P C D F 188.71 Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 1020 37 1,2,3,7,8-PeCDD 1010 61 1,2,3,6,7,8-HxCDD 1006 38 1,2,3,4,6,7,8-HpCDD 1009 39 O C D D 2004 25 2,3,7,8-TCDF 1017 33 1,2,3,7,8-PeCDF 1002 57 1,2,3,4,7,8-HxCDF 1009 40 1,2,3,4,6,7,8-HpCDF 1001 37 ND = Not Detected NDR = Concentrations are Included in Total TEQ 128 Sample Site N A Sample # Procedural Blank Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.00 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD N D 0.06 N A T C D D 0.08 0.06 1,2,3,7,8-PeCDD N D 0.08 N A PeCDD ND 0.06 1,2,3,4,7,8-HxCDD ND 0.1 N A H x C D D 0.27 0.1 1,2,3,6,7,8-HxCDD 0.16 0.1 N A H p C D D 0.3 0.12 1,2,3,7,8,9-HxCDD ND 0.1 N A O C D D 0.3 0.14 1,2,3,4,6,7,8-HpCDD 0.17 0.12 N A O C D D 0.3 0.14 N A Total P C D D 0.95 2,3,7,8-TCDF ND 0.05 N A T C D F 0.05 0.05 1,2,3,7,8-PeCDF ND 0.06 N A PeCDF ND 0.06 2,3,4,7,8-PeCDF ND 0.06 N A H x C D F ND 0.08 1,2,3,4,7,8-HxCDF N D 0.08 N A H p C D F 0.1 0.1 1,2,3,6,7,8-HxCDF N D 0.08 N A O C D F ND 0.12 2,3,4,6,7,8-HxCDF ND 0.08 N A 1,2,3,7,8,9-HxCDF N D 0.08 N A 1,2,3,4,6,7,8-HpCDF 0.1 0.1 N A 1,2,3,4,7,8,9-HpCDF ND 0.1 N A O C D F ND 0.12 N A Total T E Q N A Total P C D F 0.15 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 996 43 1,2,3,7,8-PeCDD 1011 96 1,2,3,6,7,8-HxCDD 1007 67 1,2,3,4,6,7,8-HpCDD 1008 . 82 O C D D 2012 75 2,3,7,8-TCDF 1011 38 1,2,3,7,8-PeCDF 1005 93 1,2,3,4,7,8-HxCDF 1003 73 1,2,3,4,6,7,8-HpCDF 1001 73 ND = Not Detected NDR = Concentrations are Included in Total TEQ 129 Sample Site Howe Sound Sample # DF 14-16, >63 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 5.37 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.77 0.06 7.70E-01 T C D D 42.81 0.06 1,2,3,7,8-PeCDD 1.95 0.08 1.95E+00 P e C D D 42.58 0.06 1,2,3,4,7,8-HxCDD 1.14 0.1 1.14E-01 H x C D D 243.31 0.1 1,2,3,6,7,8-HxCDD 26.67 0.1 2.67E+00 H p C D D 78.49 0.12 1,2,3,7,8,9-HxCDD 12.29 0.1 1.23E+00 O C D D 93.69 0.14 1,2,3,4,6,7,8-HpCDD 26.2 0.12 2.62E-01 O C D D 93.69 0.14 9.37E-03 Total P C D D 498.88 2,3,7,8-TCDF 30.93 0.05 3.09E+00 T C D F 78.9 0.05 1,2,3,7,8-PeCDF 1.27 0.06 6.35E-02 P e C D F 17.94 0.06 2,3,4,7,8-PeCDF 1.73 0.06 8.64E-01 H x C D F 9.51 0.08 1,2,3,4,7,8-HxCDF 0.97 0.08 9.70E-02 H p C D F 11.09 0.1 1,2,3,6,7,8-HxCDF N D 0.08 0.00E+00 O C D F 4.2 0.12 2,3,4,6,7,8-HxCDF 0.63 0.08 6.28E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 4.5 0.1 4.50E-02 1,2,3,4,7,8,9-HpCDF 0.37 0.1 3.72E-03 O C D F 4.2 0.12 4.20E-04 Total T E Q 1.12E+01 Total P C D F 119.65 Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 1004 96 1,2,3,7,8-PeCDD 1010 125 1,2,3,6,7,8-HxCDD 1008 68 1,2,3,4,6,7,8-HpCDD 1010 72 ' O C D D 2025 57 2,3,7,8-TCDF 1011 95 1,2,3,7,8-PeCDF 1011 108 1,2,3,4,7,8-HxCDF 1009 71 1,2,3,4,6,7,8-HpCDF 1003 74 ND = Not Detected NDR = Concentrations are Included in Total TEQ 130 Sample Site Howe Sound Sample # DF 14-16, 20-63 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt . Extracted (g) 10.20 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD ND 0.06 0.00E+00 T C D D 18.94 0.06 1,2,3,7,8-PeCDD 0.47 0.08 4.70E-01 PeCDD 16.77 0.06 1,2,3,4,7,8-HxCDD 0.36 0.1 3.60E-02 H x C D D 51.77 0.1 1,2,3,6,7,8-HxCDD 4.96 0.1 4.96E-01 H p C D D 14.6 0.12 1,2,3,7,8,9-HxCDD 2.62 0.1 2.62E-01 O C D D 16.6 0.14 1,2,3,4,6,7,8-HpCDD 6.02 0.12 6.02E-02 O C D D 16.6 0.14 1.66E-03 Total P C D D 118.68 2,3,7,8-TCDF 5.89 0.05 5.89E-01 T C D F 14.38 0.05 1,2,3,7,8-PeCDF 0.24 0.06 1.20E-02 PeCDF 2.74 0.06 2,3,4,7,8-PeCDF 0.31 0.06 1.55E-01 H x C D F 1.19 0.08 1,2,3,4,7,8-HxCDF 0.19 0.08 1.90E-02 H p C D F 2.47 0.1 1,2,3,6,7,8-HxCDF ND 0.08 0.00E+00 O C D F 0.88 0.12 2,3,4,6,7,8-HxCDF N D 0.08 0.00E+00 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.52 0.1 1.52E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 0.86 0.12 8.60E-05 Total T E Q 2.12E+00 Total P C D F 21.64 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1007 113 1,2,3,7,8-PeCDD 1004 141 1,2,3,6,7,8-HxCDD 1009 75 1,2,3,4,6,7,8-HpCDD 1006 89 O C D D 2015 83 2,3,7,8-TCDF 1007 102 1,2,3,7,8-PeCDF 1006 123 1,2,3,4,7,8-HxCDF 1008 70 1,2,3,4,6,7,8-HpCDF 1001 72 ND = Not Detected NDR = Concentrations are Included in Total TEQ 131 Sample Site Howe Sound Sample # DF 14-16, 10-20 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 7.98 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.46 0.06 4.60E-01 T C D D 51.51 0.06 1,2,3,7,8-PeCDD 0.81 0.08 8.12E-01 P e C D D 52.19 0.06 1,2,3,4,7,8-HxCDD 0.96 0.1 9.60E-02 H x C D D 133.57 0.1 1,2,3,6,7,8-HxCDD 9.66 0.1 9.66E-01 H p C D D 26.27 0.12 1,2,3,7,8,9-HxCDD 5.37 0.1 5.37E-01 O C D D 20.9 0.14 1,2,3,4,6,7,8-HpCDD 12.56 0.12 1.26E-01 O C D D 20.9 0.14 2.09E-03 Total P C D D 284.44 2,3,7,8-TCDF 9.98 0.05 9.98E-01 T C D F 26.59 0.05 1,2,3,7,8-PeCDF 0.58 0.06 2.92E-02 P e C D F 6.5 0.06 2,3,4,7,8-PeCDF N D 0.06 0.00E+00 H x C D F 3.05 0.08 1,2,3,4,7,8-HxCDF 0.29 0.08 2.90E-02 H p C D F 3.05 0.1 1,2,3,6,7,8-HxCDF N D 0.08 0.00E+00 O C D F 0.98 0.12 2,3,4,6,7,8-HxCDF 0.23 0.08 2.32E-20 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.36 0.1 1.36E-02 1,2,3,4,7,8,9-HpCDF 0.12 0.1 1.20E-03 O C D F 0.98 0.12 9.81E-05 Total T E Q 4.09E+00 Total P C D F 40.17 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1002 100 1,2,3,7,8-PeCDD 1003 114 1,2,3,6,7,8-HxCDD 1002 73 1,2,3,4,6,7,8-HpCDD 1005 95 O C D D 2020 87 2,3,7,8-TCDF 1004 102 1,2,3,7,8-PeCDF 1003 114 1,2,3,4,7,8-HxCDF 1003 77 1,2,3,4,6,7,8-HpCDF 1007 63 ND = Not Detected NDR = Concentrations are Included in Total TEQ 132 Sample Site Howe Sound Sample # DF 14-16, 2-10 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 7.97 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.31 0.06 3.15E-01 T C D D 23.8 0.06 1,2,3,7,8-PeCDD 0.75 0.08 7.51E-01 P e C D D 24.61 0.06 1,2,3,4,7,8-HxCDD 0.5 0.1 5.00E-02 H x C D D 107.75 0.1 1,2,3,6,7,8-HxCDD 10.27 0.1 1.03E+00 H p C D D 22.56 0.12 1,2,3,7,8,9-HxCDD 5.24 0.1 5.24E-01 O C D D 23.56 0.14 1,2,3,4,6,7,8-HpCDD 10.46 0.12 1.05E-01 O C D D 23.56 0.14 2.36E-03 Total P C D D 202.28 2,3,7,8-TCDF 8 0.05 8.00E-01 T C D F 19.61 0.05 1,2,3,7,8-PeCDF 0.48 0.06 2.38E-02 P e C D F 5.62 0.06 2,3,4,7,8-PeCDF 0.6 0.06 2.99E-01 H x C D F 2.9 0.08 1,2,3,4,7,8-HxCDF 0.28 0.08 2.80E-02 H p C D F 4.6 0.1 1,2,3,6,7,8-HxCDF N D 0.08 0.00E+00 O C D F 1.78 0.12 2,3,4,6,7,8-HxCDF 0.2 0.08 2.04E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 2.03 0.1 2.03E-02 1,2,3,4,7,8,9-HpCDF 0.13 0.1 1.25E-03 O C D F 1.78 0.12 1.78E-04 Total T E Q 3.97E+00 Total P C D F 34.52 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1007 78 1,2,3,7,8-PeCDD 1011 89 1,2,3,6,7,8-HxCDD 1013 56 1,2,3,4,6,7,8-HpCDD 1006 75 O C D D 2016 70 2,3,7,8-TCDF 1010 79 1,2,3,7,8-PeCDF 1009 88 1,2,3,4,7,8-HxCDF 1001 60 1,2,3,4,6,7,8-HpCDF 1010 66 ND = Not Detected NDR = Concentrations are Included in Total TEQ 133 Sample Site Howe Sound Sample # DF 14-16, <2 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 8.46 Congener Concentration (pg/g) DL T E Q Homologue Concentration (pg/g) DL 2,3,7,8-TCDD 0.21 0.06 2.14E-01 T C D D 2.75 0.06 1,2,3,7,8-PeCDD 0.54 0.08 5.40E-01 P e C D D 8.06 0.06 1,2,3,4,7,8-HxCDD 0.37 0.1 3.71 E-02 H x C D D 82.87 0.1 1,2,3,6,7,8-HxCDD 9.57 0.1 9.57E-01 H p C D D 23.08 0.12 1,2,3,7,8,9-HxCDD 5.73 0.1 5.73E-01 O C D D 33.77 0.14 1,2,3,4,6,7,8-HpCDD 10.06 0.12 1.01E-01 O C D D 33.77 0.14 3.38E-03 Total P C D D 150.53 2,3,7,8-TCDF 4.58 0.05 5.48E-01 T C D F 9.11 0.05 1,2,3,7,8-PeCDF 0.37 0.06 1.85E-02 P e C D F 3.99 0.06 2,3,4,7,8-PeCDF 0.42 0.06 2.11E-01 H x C D F 3.72 0.08 1,2,3,4,7,8-HxCDF 0.3 0.08 3.00E-02 H p C D F 5.56 0.1 1,2,3,6,7,8-HxCDF 0.24 0.08 2.43E-02 O C D F 1.91 0.12 2,3,4,6,7,8-HxCDF ND 0.08 0.00E+00 1,2,3,7,8,9-HxCDF 0.25 0.08 2.50E-02 1,2,3,4,6,7,8-HpCDF 2.63 0.1 2.63E-02 1,2,3,4,7,8,9-HpCDF 0.17 0.1 1.69E-03 O C D F 1.91 0.12 1.91E-04 Total T E Q 3.22E+00 Total P C D F 24.27 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1007 56 1,2,3,7,8-PeCDD 1004 67 1,2,3,6,7,8-HxCDD 1014 40 1,2,3,4,6,7,8-HpCDD 1008 52 O C D D 2007 45 2,3,7,8-TCDF 999 58 1,2,3,7,8-PeCDF 1014 61 1,2,3,4,7,8-HxCDF 996 42 1,2,3,4,6,7,8-HpCDF 999 46 ND = Not Detected NDR = Concentrations are Included in Total TEQ 134 Sample Site Howe Sound Sample # Procedural Blank Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.00 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD N D 0.06 N A T C D D ND 0.06 1,2,3,7,8-PeCDD ND 0.08 N A PeCDD ND 0.06 1,2,3,4,7,8-HxCDD ND 0.1 N A H x C D D ND 0.1 1,2,3,6,7,8-HxCDD N D 0.1 N A H p C D D ND 0.12 1,2,3,7,8,9-HxCDD ND 0.1 N A O C D D 0.37 0.14 1,2,3,4,6,7,8-HpCDD ND 0.12 N A O C D D 0.37 0.14 N A Total P C D D 0.37 2,3,7,8-TCDF N D 0.05 N A T C D F ND 0.05 1,2,3,7,8-PeCDF N D 0.06 N A PeCDF N D 0.06 2,3,4,7,8-PeCDF ND 0.06 N A H x C D F N D 0.08 1,2,3,4,7,8-HxCDF ND 0.08 N A H p C D F ND 0.1 1,2,3,6,7,8-HxCDF ND 0.08 N A O C D F ND 0.12 2,3,4,6,7,8-HxCDF N D 0.08 N A 1,2,3,7,8,9-HxCDF N D 0.08 N A 1,2,3,4,6,7,8-HpCDF N D 0.1 N A 1,2,3,4,7,8,9-HpCDF N D 0.1 N A O C D F N D 0.12 N A Total T E Q N A Total P C D F ND Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 995 95 1,2,3,7,8-PeCDD 995 112 1,2,3,6,7,8-HxCDD 995 75 1,2,3,4,6,7,8-HpCDD 995 95 O C D D 1990 89 2,3,7,8-TCDF 995 86 1,2,3,7,8-PeCDF 995 108 1,2,3,4,7,8-HxCDF 995 88 1,2,3,4,6,7,8-HpCDF 995 79 ND = Not Detected NDR = Concentrations are Included in Total TEQ 135 Sample Site Howe Sound Sample # DF 20-22, >63 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 2.58 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.93 0.06 9.30E-01 T C D D 19.87 0.06 1,2,3,7,8-PeCDD 1.94 0.08 1.94E+00 P e C D D 22.81 0.06 1,2,3,4,7,8-HxCDD 0.67 0.1 6.70E-02 H x C D D 240.11 0.1 1,2,3,6,7,8-HxCDD 30.4 0.1 3.04E+00 H p C D D 122.04 0.12 1,2,3,7,8,9-HxCDD 14.61 0.1 1.46E+00 O C D D 133.62 0.14 1,2,3,4,6,7,8-HpCDD 31.36 0.12 3.14E-01 O C D D 133.02 0.14 1.34E-02 Total P C D D 538.45 2,3,7,8-TCDF 37.13 0.05 3.71E+00 T C D F 84.81 0.05 1,2,3,7,8-PeCDF 0.95 0.06 4.75E-02 P e C D F 11.86 0.06 2,3,4,7,8-PeCDF 1.16 0.06 5.79E-01 H x C D F 8.02 0.08 1,2,3,4,7,8-HxCDF 0.46 0.08 4.60E-02 H p C D F 12.79 0.1 1,2,3,6,7,8-HxCDF 0.42 0.08 4.20E-02 O C D F 5.4 0.12 2,3,4,6,7,8-HxCDF 0.34 0.08 3.40E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 4.7 0.1 4.70E-02 1,2,3,4,7,8,9-HpCDF 0.24 0.1 2.44E-03 O C D F 5.4 0.12 1.40E-04 Total T E Q 1.23E+01 Total P C D F 122.87 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 97 1,2,3,7,8-PeCDD 995 118 1,2,3,6,7,8-HxCDD 995 73 1,2,3,4,6,7,8-HpCDD 995 92 O C D D 1990 88 2,3,7,8-TCDF 995 88 1,2,3,7,8-PeCDF 995 114 1,2,3,4,7,8-HxCDF 995 86 1,2,3,4,6,7,8-HpCDF 995 79 ND = Not Detected NDR = Concentrations are Included in Total TEQ 136 Sample Site Howe Sound Sample # DF 20-22, 20-63 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.99 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.26 0.06 2.61E-01 T C D D 4.53 0.06 1,2,3,7,8-PeCDD 0.51 0.08 5.09E-01 P e C D D 6.79 0.06 1,2,3,4,7,8-HxCDD 0.19 0.1 1.90E-02 H x C D D 76.55 0.1 1,2,3,6,7,8-HxCDD 9.95 0.1 9.95E-01 H p C D D 17.53 0.12 1,2,3,7,8,9-HxCDD 4.52 0.1 4.52E-01 O C D D 23.77 0.14 1,2,3,4,6,7,8-HpCDD 6.54 0.12 6.54E-02 O C D D 23.77 0.14 2.38E-03 Total P C D D 129.17 2,3,7,8-TCDF 8.4 0.05 8.40E-01 T C D F 19.74 0.05 1,2,3,7,8-PeCDF 0.31 0.06 1.55E-02 P e C D F 3.7 0.06 2,3,4,7,8-PeCDF 0.36 0.06 1.80E-01 H x C D F 2.79 0.08 1,2,3,4,7,8-HxCDF 0.18 0.08 1.80E-02 H p C D F 4.6 0.1 1,2,3,6,7,8-HxCDF 0.13 0.08 1.30E-02 O C D F 1.74 0.12 2,3,4,6,7,8-HxCDF 0.16 0.08 1.60E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.82 0.1 1.82E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 1.74 0.12 1.74E-04 Total T E Q 3.40E+00 Total P C D F 32.57 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 82 1,2,3,7,8-PeCDD 995 111 1,2,3,6,7,8-HxCDD 995 70 1,2,3,4,6,7,8-HpCDD 995 86 O C D D 1990 79 2,3,7,8-TCDF 995 82 1,2,3,7,8-PeCDF 995 108 1,2,3,4,7,8-HxCDF 995 81 1,2,3,4,6,7,8-HpCDF 995 74 ND = Not Detected NDR = Concentrations are Included in Total T E Q 137 Sample Site Howe Sound Sample* DF 20-22, 10-20 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt . Extracted (g) 10.01 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.18 0.06 1.80E-01 T C D D 3.13 0.06 1,2,3,7,8-PeCDD 0.35 0.08 3.49E-01 PeCDD 4.54 0.06 1,2,3,4,7,8-HxCDD 0.11 0.1 1.10E-20 H x C D D 56.15 0.1 1,2,3,6,7,8-HxCDD 7.45 0.1 7.45E-01 H p C D D 9.37 0.12 1,2,3,7,8,9-HxCDD 3.73 0.1 3.73E-01 O C D D 10.67 0.14 1,2,3,4,6,7,8-HpCDD 3.8 0.12 3.80E-02 O C D D 10.67 0.14 1.07E-03 Total P C D D 83.87 2,3,7,8-TCDF 5.45 0.05 5.45E-01 T C D F 13.03 0.05 1,2,3,7,8-PeCDF 0.16 0.06 8.00E-03 PeCDF 2.28 0.06 2,3,4,7,8-PeCDF 0.28 0.06 1.41E-01 H x C D F 1.44 0.08 1,2,3,4,7,8-HxCDF 0.12 0.08 1.20E-02 H p C D F 2.21 0.1 1,2,3,6,7,8-HxCDF 0.08 0.08 8.00E-03 O C D F 0.67 0.12 2,3,4,6,7,8-HxCDF N D 0.08 0.00E+00 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.94 0.1 9.45E-03 1,2,3,4,7,8,9-HpCDF ND 0.1 0.00E+00 O C D F 0.67 0.12 6.69E-03 Total T E Q 2.42E+00 Total P C D F 19.63 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 86 1,2,3,7,8-PeCDD 995 103 1,2,3,6,7,8-HxCDD 995 64 1,2,3,4,6,7,8-HpCDD 995 80 O C D D 1990 74 2,3,7,8-TCDF 995 80 1,2,3,7,8-PeCDF 995 101 1,2,3,4,7,8-HxCDF 995 73 1,2,3,4,6,7,8-HpCDF 995 67 ND = Not Detected NDR = Concentrations are Included in Total TEQ 138 Sample Site Howe Sound Sample # DF 20-22, 2-10 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.99 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.24 0.06 2.36E-01 T C D D 3.18 0.06 1,2,3,7,8-PeCDD 0.46 0.08 4.55E-01 PeCDD 5.18 0.06 1,2,3,4,7,8-HxCDD 0.24 0.1 2.40E-02 H x C D D 70.58 0.1 1,2,3,6,7,8-HxCDD 9.51 0.1 9.51E-01 H p C D D 11.54 0.12 1,2,3,7,8,9-HxCDD 4.8 0.1 4.80E-01 O C D D 12.71 0.14 1,2,3,4,6,7,8-HpCDD 4.93 0.12 4.93E-02 O C D D 12.71 0.14 1.27E-03 Total P C D D 103.19 2,3,7,8-TCDF 6.33 0.05 6.33E-01 T C D F 14.53 0.05 1,2,3,7,8-PeCDF 0.24 0.06 1.18E-02 PeCDF 2.9 0.06 2,3,4,7,8-PeCDF 0.28 0.06 1.39E-01 H x C D F 2.75 0.08 1,2,3,4,7,8-HxCDF 0.15 0.08 1.50E-02 H p C D F 9.94 0.1 1,2,3,6,7,8-HxCDF 0.1 0.08 1.00E-02 O C D F 2.47 0.12 2,3,4,6,7,8-HxCDF 0.12 0.08 1.20E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 2.26 0.1 2.26E-02 1,2,3,4,7,8,9-HpCDF 0.12 0.1 1.17E-03 O C D F 2.47 0.12 2.47E-04 Total T E Q 3.04E+00 Total P C D F 32.59 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 75 1,2,3,7,8-PeCDD 995 87 1,2,3,6,7,8-HxCDD 995 55 1,2,3,4,6,7,8-HpCDD 995 71 O C D D 1990 68 2,3,7,8-TCDF 995 69 1,2,3,7,8-PeCDF 995 84 1,2,3,4,7,8-HxCDF 995 83 1,2,3,4,6,7,8-HpCDF 995 60 ND = Not Detected NDR = Concentrations are Included in Total TEQ 139 Sample Site Howe Sound Sample* DF 20-22, 2-10 Micrometres Rep. Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.01 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.19 0.06 1.91E-01 T C D D 1.82 0.06 1,2,3,7,8-PeCDD 0.36 0.08 3.60E-01 PeCDD 3.88 0.06 1,2,3,4,7,8-HxCDD ND 0.1 0.00E+00 H x C D D 65.4 0.1 1,2,3,6,7,8-HxCDD 8.84 0.1 8.84E-01 H p C D D 10.56 0.12 1,2,3,7,8,9-HxCDD 4.5 0.1 4.50E-01 O C D D 13 0.14 1,2,3,4,6,7,8-HpCDD 4.67 0.12 4.67E-02 O C D D 13 0.14 1.30E-03 Total P C D D 94.66 2,3,7,8-TCDF 5.62 0.05 5.62E-01 T C D F 12.28 0.05 1,2,3,7,8-PeCDF 0.22 0.06 1.10E-02 PeCDF 2.11 0.06 2,3,4,7,8-PeCDF 0.23 0.06 1.15E-01 H x C D F 2.1 0.08 1,2,3,4,7,8-HxCDF 0.16 0.08 1.60E-02 H p C D F 5.17 0.1 1,2,3,6,7,8-HxCDF 0.09 0.08 9.00E-03 O C D F 2.15 0.12 2,3,4,6,7,8-HxCDF 0.08 0.08 8.00E-03 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.67 0.1 1.67E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 2.15 0.12 2.15E-04 Total T E Q 2.67E+00 Total P C D F 23.81 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 93 1,2,3,7,8-PeCDD 995 110 1,2,3,6,7,8-HxCDD 995 71 1,2,3,4,6,7,8-HpCDD 995 92 O C D D 1990 85 2,3,7,8-TCDF 995 84 1,2,3,7,8-PeCDF 995 108 1,2,3,4,7,8-HxCDF 995 81 1,2,3,4,6,7,8-HpCDF 995 78 ND = Not Detected NDR = Concentrations are Included in Total TEQ 140 Sample Site Howe Sound Sample # DF 20-22, <2 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 6.76 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.29 0.06 2.90E-01 T C D D 2.17 0.06 1,2,3,7,8-PeCDD 0.79 0.08 7.91E-01 P e C D D 6.43 0.06 1,2,3,4,7,8-HxCDD N D 0.1 0.00E+00 H x C D D 141.65 0.1 1,2,3,6,7,8-HxCDD 18.87 0.1 1.89E+00 H p C D D 28.42 0.12 1,2,3,7,8,9-HxCDD 9.51 0.1 9.51E-01 O C D D 37.55 0.14 1,2,3,4,6,7,8-HpCDD 11.46 0.12 1.15E-01 O C D D 37.55 0.14 3.76E-03 Total P C D D 216.22 2,3,7,8-TCDF 8.31 0.05 8.31E-01 T C D F 18.4 0.05 1,2,3,7,8-PeCDF 0.39 0.06 1.95E-02 P e C D F 3.82 0.06 2,3,4,7,8-PeCDF 0.39 0.06 1.96E-01 H x C D F 4.75 0.08 1,2,3,4,7,8-HxCDF 0.29 0.08 2.90E-02 H p C D F 9.46 0.1 1,2,3,6,7,8-HxCDF 0.2 0.08 2.00E-02 O C D F 3.54 0.12 2,3,4,6,7,8-HxCDF 0.17 0.08 1.70E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 3.57 0.1 3.57E-02 1,2,3,4,7,8,9-HpCDF 0.19 0.1 1.86E-03 O C D F 3.54 0.12 3.54E-04 Total T E Q 5.19E+00 Total P C D F 39.97 Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 995 92 1,2,3,7,8-PeCDD 995 109 1,2,3,6,7,8-HxCDD 995 67 1,2,3,4,6,7,8-HpCDD 995 68 O C D D 1990 49 2,3,7,8-TCDF 995 83 1,2,3,7,8-PeCDF 995 103 1,2,3,4,7,8-HxCDF 995 72 1,2,3,4,6,7,8-HpCDF 995 64 ND = Not Detected NDR = Concentrations are Included in Total TEQ 141 Sample Site Howe Sound Sample # DF 34-36, >63 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 8.79 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.21 0.06 2.10E-01 T C D D 4.83 0.06 1,2,3,7,8-PeCDD 0.79 0.08 7.94E-01 P e C D D 9.22 0.06 1,2,3,4,7,8-HxCDD 0.37 0.1 3.70E-02 H x C D D 110.04 0.1 1,2,3,6,7,8-HxCDD 12.72 0.1 1.27E+00 H p C D D 30.19 0.12 1,2,3,7,8,9-HxCDD 5.97 0.1 5.97E-01 O C D D 29.42 0.14 1,2,3,4,6,7,8-HpCDD 11.88 0.12 1.19E-01 O C D D 29.42 0.14 2.94E-03 Total P C D D 183.7 2,3,7,8-TCDF 13.9 0.05 1.39E+00 T C D F 33.07 0.05 1,2,3,7,8-PeCDF 0.53 0.06 2.65E-02 P e C D F 5.61 0.06 2,3,4,7,8-PeCDF 0.53 0.06 2.64E-01 H x C D F 4.35 0.08 1,2,3,4,7,8-HxCDF 0.4 0.08 4.00E-02 H p C D F 5.43 0.1 1,2,3,6,7,8-HxCDF 0.26 0.08 2.80E-02 O C D F 1.63 0.12 2,3,4,6,7,8-HxCDF 0.26 0.08 2.60E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 2.65 0.1 2.65E-02 1,2,3,4,7,8,9-HpCDF 0.15 0.1 1.54E-03 O C D F 1.63 0.12 1.63E-04 Total T E Q 4.83E+00 Total P C D F 50.09 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 92 1,2,3,7,8-PeCDD 995 105 1,2,3,6,7,8-HxCDD 995 71 1,2,3,4,6,7,8-HpCDD 995 79 O C D D 1990 70 2,3,7,8-TCDF 995 85 1,2,3,7,8-PeCDF 995 101 1,2,3,4,7,8-HxCDF 995 82 1,2,3,4,6,7,8-HpCDF 995 70 N D = Not Detected NDR = Concentrations are Included in Total TEQ 142 Sample Site Howe Sound Sample # DF 34-36, 20-63 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.99 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD NDR(0.09) 0.06 9.00E-02 T C D D 1.46 0.06 1,2,3,7,8-PeCDD 0.26 0.08 2.64E-01 PeCDD 3.67 0.06 1,2,3,4,7,8-HxCDD 0.22 0.1 2.17E-02 H x C D D 36.41 0.1 1,2,3,6,7,8-HxCDD 3.97 0.1 3.97E-01 H p C D D 10.07 0.12 1,2,3,7,8,9-HxCDD 2.16 0.1 2.16E-01 O C D D 11.77 0.14 1,2,3,4,6,7,8-HpCDD 5.12 0.12 5.12E-02 O C D D 11.77 0.14 1.18E-03 Total P C D D 36.37 2,3,7,8-TCDF 3.45 0.05 3.45E-01 T C D F 8.29 0.05 1,2,3,7,8-PeCDF 0.21 0.06 1.05E-02 PeCDF 2.19 0.06 2,3,4,7,8-PeCDF 0.2 0.06 9.91 E-02 H x C D F 2.17 0.08 1,2,3,4,7,8-HxCDF 0.46 0.08 4.60E-02 H p C D F 1.95 0.1 1,2,3,6,7,8-HxCDF 0.27 0.08 2.70E-02 O C D F 0.56 0.12 2,3,4,6,7,8-HxCDF 0.17 0.08 1.70E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.17 0.1 1.17E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 0.56 0.12 5.60E-05 Total T E Q 1.60+00 Total P C D F 15.17 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 93 1,2,3,7,8-PeCDD 995 111 1,2,3,6,7,8-HxCDD 995 68 1,2,3,4,6,7,8-HpCDD 995 83 O C D D 1990 70 2,3,7,8-TCDF 995 82 1,2,3,7,8-PeCDF 995 106 1,2,3,4,7,8-HxCDF 995 79 1,2,3,4,6,7,8-HpCDF 995 72 N D = Not Detected NDR = Concentrations are Included in Total TEQ 143 Sample Site Howe Sound Sample # DF 34-36, 10-20 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.04 Congener Concentration (pg/g) DL T E Q Homologue Concentration (pg/g) DL 2,3,7,8-TCDD ND 0.06 0.00E+00 T C D D 1.45 0.06 1,2,3,7,8-PeCDD 0.23 0.08 2.30E-01 PeCDD 3.37 0.06 1,2,3,4,7,8-HxCDD 0.18 0.1 1.80E-02 H x C D D 32.44 0.1 1,2,3,6,7,8-HxCDD 3.23 0.1 3.23E-01 H p C D D 8.73 0.12 1,2,3,7,8,9-HxCDD 1.96 0.1 1.96E-01 O C D D 9.97 0.14 1,2,3,4,6,7,8-HpCDD 4.64 0.12 4.64E-02 O C D D 9.97 0.14 9.97E-04 Total P C D D 55.96 2,3,7,8-TCDF 2.86 0.05 2.86E-01 T C D F 7.14 0.05 1,2,3,7,8-PeCDF 0.19 0.06 9.50E-03 PeCDF 1.73 0.06 2,3,4,7,8-PeCDF 0.15 0.06 7.74E-02 H x C D F 1.48 0.08 1,2,3,4,7,8-HxCDF 0.27 0.08 2.70E-02 H p C D F 2.01 0.1 1,2,3,6,7,8-HxCDF NDR(0.14) 0.08 1.40E-02 O C D F 0.61 0.12 2,3,4,6,7,8-HxCDF 0.13 0.08 1.30E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 0.14 0.1 1.14E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 0.61 0.12 6.06E-05 Total T E Q 1.25E+00 Total P C D F 12.97 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 87 1,2,3,7,8-PeCDD 995 104 1,2,3,6,7,8-HxCDD 995 64 1,2,3,4,6,7,8-HpCDD 995 80 O C D D 1990 71 2,3,7,8-TCDF 995 81 1,2,3,7,8-PeCDF 995 104 1,2,3,4,7,8-HxCDF 995 77 1,2,3,4,6,7,8-HpCDF 995 68 ND = Not Detected NDR = Concentrations are Included in Total TEQ 144 Sample Site Howe Sound Sample* DF 34-36, 2-10 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.99 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.096 0.06 9.00E-02 T C D D 1.2 0.06 1,2,3,7,8-PeCDD 0.23 0.08 2.31E-01 P e C D D 3.21 0.06 1,2,3,4,7,8-HxCDD 0.22 0.1 2.21 E-02 H x C D D 39.55 0.1 1,2,3,6,7,8-HxCDD 4.32 0.1 4.32E-01 H p C D D 10.54 0.12 1,2,3,7,8,9-HxCDD 2.54 0.1 2.54E-01 O C D D 12.01 0.14 1,2,3,4,6,7,8-HpCDD 5.43 0.12 5.43E-02 O C D D 12.01 0.14 1.20E-03 Total P C D D 66.51 2,3,7,8-TCDF 2.93 0.05 2.93E-01 T C D F 6.73 0.05 1,2,3,7,8-PeCDF 0.23 0.06 1.13E-02 P e C D F 1.79 0.06 2,3,4,7,8-PeCDF 0.19 0.06 9.30E-02 H x C D F 1.76 0.08 1,2,3,4,7,8-HxCDF 0.28 0.08 2.80E-02 H p C D F 2.32 0.1 1,2,3,6,7,8-HxCDF 0.2 0.08 2.00E-02 O C D F 0.74 0.12 2,3,4,6,7,8-HxCDF 0.14 0.08 1.40E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 1.24 0.1 1.24E-02 1,2,3,4,7,8,9-HpCDF 0.11 0.1 1.05E-03 O C D F 0.74 0.12 7.45E-05 Total T E Q 1.58E+00 Total P C D F 13.34 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 87 1,2,3,7,8-PeCDD 995 103 1,2,3,6,7,8-HxCDD 995 66 1,2,3,4,6,7,8-HpCDD 995 79 O C D D 1990 70 2,3,7,8-TCDF 995 78 1,2,3,7,8-PeCDF 995 100 1,2,3,4,7,8-HxCDF 995 73 1,2,3,4,6,7,8-HpCDF 995 70 N D = Not Detected NDR = Concentrations are Included in Total TEQ 145 Sample Site Howe Sound Sample* DF 34-36, <2 Micrometres Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 9.99 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 0.09 0.06 9.00E-02 T C D D 0.64 0.06 1,2,3,7,8-PeCDD 0.29 0.08 2.89E-01 PeCDD 3.25 0.06 1,2,3,4,7,8-HxCDD 0.26 0.1 2.58E-02 H x C D D 50.07 0.1 1,2,3,6,7,8-HxCDD 5.79 0.1 5.79E-01 H p C D D 15.06 0.12 1,2,3,7,8,9-HxCDD 3.52 0.1 3.52E-01 O C D D 19.72 0.14 1,2,3,4,6,7,8-HpCDD 7.42 0.12 7.42E-02 O C D D 19.72 0.14 1.97E-03 Total P C D D 88.74 2,3,7,8-TCDF 2.89 0.05 2.89E-01 T C D F 6.15 0.05 1,2,3,7,8-PeCDF 0.25 0.06 1.25E-02 PeCDF 2.07 0.06 2,3,4,7,8-PeCDF 0.2 0.06 1.01E-01 H x C D F 2.65 0.08 1,2,3,4,7,8-HxCDF 0.42 0.08 4.20E-02 H p C D F 3.7 0.1 1,2,3,6,7,8-HxCDF 0.2 0.08 2.00E-02 O C D F 1.24 0.12 2,3,4,6,7,8-HxCDF 0.23 0.08 2.30E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 2.02 0.1 2.02E-02 1,2,3,4,7,8,9-HpCDF 0.12 0.1 1.20E-03 O C D F 1.24 0.12 1.24E-04 Total T E Q 1.92E+00 Total P C D F 15.8 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 995 88 1,2,3,7,8-PeCDD 995 76 1,2,3,6,7,8-HxCDD 995 47 1,2,3,4,6,7,8-HpCDD 995 51 O C D D 1990 40 2,3,7,8-TCDF 995 67 1,2,3,7,8-PeCDF 995 76 1,2,3,4,7,8-HxCDF 995 49 1,2,3,4,6,7,8-HpCDF 995 44 ND = Not Detected NDR = Concentrations are Included in Total TEQ 146 Sample Site Howe Sound Sample # D F 46-48, >63 Micrometres Analysis Laboratory I.O.S. Regional Contaminants Laboratory Sample Net Wt. Extracted (g) 8.12 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 4.33 0.06 4.33E+00 T C D D 45.23 0.06 1,2,3,7,8-PeCDD 9.67 0.08 9.67E+00 P e C D D 99.19 0.06 1,2,3,4,7,8-HxCDD 2.37 0.1 2.37E-01 H x C D D 1480.52 0.1 1,2,3,6,7,8-HxCDD 189.81 0.1 1.90E+01 H p C D D 170.34 0.12 1,2,3,7,8,9-HxCDD 70.75 0.1 7.07E+00 O C D D 200.82 0.14 1,2,3,4,6,7,8-HpCDD 72.74 0.12 7.27E-01 O C D D 200.92 0.14 2.01 E-02 Total P C D D 1996.2 2,3,7,8-TCDF 215.14 0.05 2.15E+01 T C D F 476.65 0.05 1,2,3,7,8-PeCDF 4.92 0.06 2.46E-01 P e C D F 57.23 0.06 2,3,4,7,8-PeCDF 7.14 0.06 3.57E+00 H x C D F 38.41 0.08 1,2,3,4,7,8-HxCDF 1.27 0.08 1.27E-01 H p C D F 44.36 0.1 1,2,3,6,7,8-HxCDF 1.03 0.08 1.03E-01 O C D F 13.97 0.12 2,3,4,6,7,8-HxCDF 1.03 0.08 1.03E-01 1,2,3,7,8,9-HxCDF NDR(0.13) 0.08 1.30E-02 1,2,3,4,6,7,8-HpCDF 17.98 0.1 1.80E-01 1,2,3,4,7,8,9-HpCDF NDR(0.59) 0.1 5.90E-03 O C D F 13.97 0.12 1.40E-03 Total T E Q 6.69E+01 Total P C D F 630.63 Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 1004 83 1,2,3,7,8-PeCDD 1006 106 1,2,3,6,7,8-HxCDD 1015 58 1,2,3,4,6,7,8-HpCDD 1010 54 O C D D 2014 27 2,3,7,8-TCDF 1007 89 1,2,3,7,8-PeCDF 1007 94 1,2,3,4,7,8-HxCDF 1004 56 1,2,3,4,6,7,8-HpCDF 1009 53 ND = Not Detected NDR = Concentrations are Included in Total TEQ 147 Sample Site Howe Sound Sample # DF 46-48, 20-63 Micrometres Analysis Laboratory I.O.S. Regional Contaminants Laboratory Sample Net Wt. Extracted (g) 8.28 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 1.26 0.06 1.26E+00 T C D D 11.05 0.06 1,2,3,7,8-PeCDD 2.39 0.08 2.39E+00 P e C D D 25.34 0.06 1,2,3,4,7,8-HxCDD N D 0.1 0.00E+00 H x C D D 515.65 0.1 1,2,3,6,7,8-HxCDD 61.03 0.1 6.10E+00 H p C D D 42.99 0.12 1,2,3,7,8,9-HxCDD 27.14 0.1 2.71E+00 O C D D 52.77 0.14 1,2,3,4,6,7,8-HpCDD 20.08 0.12 2.01E-01 O C D D 52.77 0.14 5.28E-03 Total P C D D 647.8 2,3,7,8-TCDF 61.05 0.05 6.11E+00 T C D F 119.34 0.05 1,2,3,7,8-PeCDF 1.29 0.06 6.45E-02 P e C D F 12.72 0.06 2,3,4,7,8-PeCDF 1.62 0.06 8.10E-01 H x C D F 6.92 0.08 1,2,3,4,7,8-HxCDF 0.22 0.08 2.20E-02 H p C D F 13.98 0.1 1,2,3,6,7,8-HxCDF 0.24 0.08 2.40E-02 O C D F 5.28 0.12 2,3,4,6,7,8-HxCDF NDR(0.14) 0.08 1.40E-02 1,2,3,7,8,9-HxCDF ND 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 5.36 0.1 5.36E-02 1,2,3,4,7,8,9-HpCDF N D 0.1 0.00E+00 O C D F 5.28 0.12 5.28E-04 Total T E Q 1.98E+01 Total P C D F 158.24 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1001 86 1,2,3,7,8-PeCDD 1006 81 1,2,3,6,7,8-HxCDD 1002 72 1,2,3,4,6,7,8-HpCDD 1001 65 O C D D 2017 31 2,3,7,8-TCDF 1007 95 1,2,3,7,8-PeCDF 1004 71 1,2,3,4,7,8-HxCDF 1011 91 1,2,3,4,6,7,8-HpCDF 1000 60 ND = Not Detected NDR = Concentrations are Included in Total TEQ 148 Sample Site Howe Sound Sample # DF 46-48, 10-20 Micrometres Analysis Laboratory I.O.S. Regional Contaminants Laboratory Sample Net Wt . Extracted (g) 8.10 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 1.32 0.06 1.32E+00 T C D D 9.73 0.06 1,2,3,7,8-PeCDD 2.96 0.08 2.96E+00 PeCDD 26.47 0.06 1,2,3,4,7,8-HxCDD N D 0.1 0.00E+00 H x C D D 551.35 0.1 1,2,3,6,7,8-HxCDD 72.4 0.1 7.24E+00 H p C D D 49.88 0.12 1,2,3,7,8,9-HxCDD 33.23 0.1 3.32E+00 O C D D 58.37 0.14 1,2,3,4,6,7,8-HpCDD 24.66 0.12 2.47E-01 O C D D 58.37 0.14 5.84E-03 Total P C D D 695.8 2,3,7,8-TCDF 63 0.05 6.30E+00 T C D F 121.23 0.05 1,2,3,7,8-PeCDF 1.47 0.06 8.47E-02 PeCDF 13.48 0.06 2,3,4,7,8-PeCDF 1.94 0.06 9.71E-01 H x C D F 10.51 0.08 1,2,3,4,7,8-HxCDF 0.4 0.08 6.14E-02 H p C D F 14.59 0.1 1,2,3,6,7,8-HxCDF 0.33 0.08 3.28E-02 O C D F 4.01 0.12 2,3,4,6,7,8-HxCDF 0.35 0.08 3.52E-02 1,2,3,7,8,9-HxCDF ND 0.08 6.70E-03 1,2,3,4,6,7,8-HpCDF 6.25 0.1 6.25E-02 1,2,3,4,7,8,9-HpCDF 0.24 0.1 2.60E-03 O C D F 4.01 0.12 4.01E-04 Total T E Q 2.26E+01 Total P C D F 163.83 Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 1008 95 1,2,3,7,8-PeCDD 1003 108 1,2,3,6,7,8-HxCDD 1013 67 1,2,3,4,6,7,8-HpCDD 1004 88 O C D D 2017 78 2,3,7,8-TCDF 1008 95 1,2,3,7,8-PeCDF 1003 110 1,2,3,4,7,8-HxCDF 1008 71 1,2,3,4,6,7,8-HpCDF 1004 78 ND = Not Detected NDR = Concentrations are Included in Total TEQ 149 Sample Site Howe Sound Sample # DF 46-48, 2-10 Micrometres Analysis Laboratory I.O.S. Regional Contaminants Laboratory Sample Net Wt. Extracted (g) 9.02 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 1.34 0.06 1.34E+00 T C D D 6.63 0.06 1,2,3,7,8-PeCDD 3.05 0.08 3.05E+00 PeCDD 23.59 0.06 1,2,3,4,7,8-HxCDD 0.75 0.1 7.50E-02 H x C D D 654.83 0.1 1,2,3,6,7,8-HxCDD 84.23 0.1 8.42E+00 H p C D D 62.9 0.12 1,2,3,7,8,9-HxCDD 43.07 0.1 4.31E+00 O C D D 74.81 0.14 1,2,3,4,6,7,8-HpCDD 31.45 0.12 3.15E-01 O C D D 74.81 0.14 7.48E-01 Total P C D D 822.76 2,3,7,8-TCDF 56.55 0.05 5.66E+00 T C D F 103.37 0.05 1,2,3,7,8-PeCDF 1.54 0.06 7.70E-02 PeCDF 12.52 0.06 2,3,4,7,8-PeCDF 1.9 0.06 9.52E-01 H x C D F 12.95 0.08 1,2,3,4,7,8-HxCDF 0.48 0.08 4.80E-02 H p C D F 22.84 0.1 1,2,3,6,7,8-HxCDF 0.35 0.08 3.53E-02 O C D F 6.67 0.12 2,3,4,6,7,8-HxCDF 0.34 0.08 3.36E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 10.04 0.1 1.00E-01 1,2,3,4,7,8,9-HpCDF 0.29 0.1 2.91E-03 O C D F 6.67 0.12 6.67E-04 Total T E Q 2.44E+01 Total P C D F 158.34 Surrogate Amount A d d e d (pg) % Rec. 2,3,7,8-TCDD 1011 88 1,2,3,7,8-PeCDD 1009 102 1,2,3,6,7,8-HxCDD 999 62 1,2,3,4,6,7,8-HpCDD 1010 78 O C D D 2000 65 2,3,7,8-TCDF 1005 87 1,2,3,7,8-PeCDF 1011 101 1,2,3,4,7,8-HxCDF 1001 65 1,2,3,4,6,7,8-HpCDF 1006 70 ND = Not Detected NDR = Concentrations are Included in Total TEQ 150 Sample Site Howe Sound Sample # DF 46-48, 2-10 Micrometres Rep. Analysis Laboratory I.O.S. Regional Contaminants Laboratory Sample Net Wt . Extracted (g) 8.48 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 1.34 0.06 1.34E+00 T C D D 7.46 0.06 1,2,3,7,8-PeCDD 3.13 0.08 3.13E+00 PeCDD 24.37 0.06 1,2,3,4,7,8-HxCDD 0.77 0.1 7.70E-02 H x C D D 675.38 0.1 1,2,3,6,7,8-HxCDD 88.65 0.1 8.86E+00 H p C D D 67.32 0.12 1,2,3,7,8,9-HxCDD 43.74 0.1 4.37E+00 O C D D 117.93 0.14 1,2,3,4,6,7,8-HpCDD 34.05 0.12 3.40E-01 O C D D 117.93 0.14 1.18E-02 Total P C D D 892.45 2,3,7,8-TCDF 56.89 0.05 5.69E+00 T C D F 100.87 0.05 1,2,3,7,8-PeCDF 1.62 0.06 8.10E-02 PeCDF 12.94 0.06 2,3,4,7,8-PeCDF 1.93 0.06 9.65E-01 H x C D F 12.77 0.08 1,2,3,4,7,8-HxCDF 0.47 0.08 4.70E-02 H p C D F 25.13 0.1 1,2,3,6,7,8-HxCDF 0.34 0.08 3.44E-02 O C D F 6.77 0.12 2,3,4,6,7,8-HxCDF 0.34 0.08 3.41E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 11.13 0.1 1.11E-01 1,2,3,4,7,8,9-HpCDF 0.32 0.1 3.24E-03 O C D F 6.77 0.12 6.77E-04 Total T E Q 2.51E+01 Total P C D F 157.46 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1008 95 1,2,3,7,8-PeCDD 1007 111 1,2,3,6,7,8-HxCDD 1011 67 1,2,3,4,6,7,8-HpCDD 1012 90 O C D D 2022 84 2,3,7,8-TCDF 1009 97 1,2,3,7,8-PeCDF 1009 112 1,2,3,4,7,8-HxCDF 1009 73 1,2,3,4,6,7,8-HpCDF 1005 80 ND = Not Detected NDR = Concentrations are Included in Total TEQ 151 Sample Site Howe Sound Sample # DF 46-48, <2 Micrometres Analysis Laboratory I.O.S. Regional Contaminants Laboratory Sample Net Wt . Extracted (g) 8.50 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD 2.01 0.06 2.01E+00 T C D D 9.47 0.06 1,2,3,7,8-PeCDD 5.04 0.08 5.04E+00 PeCDD 37.29 0.06 1,2,3,4,7,8-HxCDD 1.04 0.1 1.04E-01 H x C D D 1257.14 0.1 1,2,3,6,7,8-HxCDD 151.31 0.1 1.51E-01 H p C D D 159.89 0.12 1,2,3,7,8,9-HxCDD 74.26 0.1 7.46E+00 O C D D 214.12 0.14 1,2,3,4,6,7,8-HpCDD 75.54 0.12 7.55E-01 O C D D 214.12 0.14 2.14E-02 Total P C D D 1677.92 2,3,7,8-TCDF 71.13 0.05 7.11E+00 T C D F 135.32 0.05 1,2,3,7,8-PeCDF 2.59 0.06 1.30E-01 PeCDF 22.85 0.06 2,3,4,7,8-PeCDF 3.29 0.06 1.64E+00 H x C D F 28.6 0.08 1,2,3,4,7,8-HxCDF 0.97 0.08 9.70E-02 H p C D F 48.11 0.1 1,2,3,6,7,8-HxCDF 0.69 0.08 6.90E-02 O C D F 16.14 0.12 2,3,4,6,7,8-HxCDF 0.71 0.08 7.14E-02 1,2,3,7,8,9-HxCDF N D 0.08 0.00E+00 1,2,3,4,6,7,8-HpCDF 19.21 0.1 1.92E-01 1,2,3,4,7,8,9-HpCDF 0.57 0.1 5.70E-03 O C D F 18.14 0.12 1.81 E-03 Total T E Q 3.98E+01 Total P C D F 253.03 Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 2012 86 1,2,3,7,8-PeCDD 2005 106 1,2,3,6,7,8-HxCDD 2031 48 1,2,3,4,6,7,8-HpCDD 2037 36 O C D D 3982 18 2,3,7,8-TCDF 2007 ' 86 1,2,3,7,8-PeCDF 2020 89 1,2,3,4,7,8-HxCDF 1993 45 1,2,3,4,6,7,8-HpCDF 1996 41 ND = Not Detected NDR = Concentrations are Included in Total TEQ 152 Sample Site N A Sample # Procedural Blank Analysis Laboratory I.O.S. Regional Contaminant Laboratory Sample Net Wt. Extracted (g) 10.00 Congener Concentration (pg/g) D L T E Q Homologue Concentration (pg/g) D L 2,3,7,8-TCDD N D 0.06 N A T C D D 0.12 0.06 1,2,3,7,8-PeCDD N D 0.08 N A PeCDD ND 0.06 1,2,3,4,7,8-HxCDD ND 0.1 N A H x C D D 0.14 0.1 1,2,3,6,7,8-HxCDD 0.14 0.1 N A H p C D D ND 0.12 1,2,3,7,8,9-HxCDD N D 0.1 N A O C D D 0.25 0.14 1,2,3,4,6,7,8-HpCDD N D 0.12 N A O C D D 0.25 0.14 N A Total P C D D 0.51 2,3,7,8-TCDF N D 0.05 N A T C D F ND 0.05 1,2,3,7,8-PeCDF N D 0.06 N A PeCDF ND 0.06 2,3,4,7,8-PeCDF N D 0.06 N A H x C D F ND 0.08 1,2,3,4,7,8-HxCDF ND 0.08 N A H p C D F N D 0.1 1,2,3,6,7,8-HxCDF ND 0.08 N A O C D F ND 0.12 2,3,4,6,7,8-HxCDF N D 0.08 N A 1,2,3,7,8,9-HxCDF N D 0.08 N A 1,2,3,4,6,7,8-HpCDF N D 0.1 N A 1,2,3,4,7,8,9-HpCDF ND 0.1 N A O C D F N D 0.12 N A Total P C D F ND Total T E Q N A Surrogate Amount Added (pg) % Rec. 2,3,7,8-TCDD 1008 78 1,2,3,7,8-PeCDD 1005 93 1,2,3,6,7,8-HxCDD 1010 57 1,2,3,4,6,7,8-HpCDD 1006 82 O C D D 2012 88 2,3,7,8-TCDF 1003 81 1,2,3,7,8-PeCDF 1003 90 1,2,3,4,7,8-HxCDF 999 62 1,2,3,4,6,7,8-HpCDF 1011 71 ND = Not Detected NDR = Concentrations are Included in Total TEQ 153
Thesis/Dissertation
eng
Oceanography
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Graduate
An examination of the role of sediment surface area in controlling the preservation of organic matter in a paralic environment and its influence on petroleum source rock formation and contaminant adsorption, Howe Sound, British Columbia
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