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2007 Field Season in the Hamilton Harbour Area of Concern PCB and PAH water monitoring undertaken by the Ontario Ministry of the Environment to support mass balance work by the Hamilton Harbour Remedial Action Plan (RAP) on PAH contamination at Randle Reef and PCB contamination in Windermere Arm

Prepared by: Tanya Labencki Environmental Monitoring and Reporting Branch Ontario Ministry of the Environment For: Hamilton Harbour Remedial Action Plan Toxic Substances and Sediment Technical Team December 2009


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2007 Field Season in the Hamilton Harbour Area of Concern PCB and PAH water monitoring undertaken by the Ontario Ministry of the Environment to support mass balance work by the Hamilton Harbour Remedial Action Plan (RAP) on PAH contamination at Randle Reef and PCB contamination in Windermere Arm

December 2009

Prepared by: Tanya Labencki Environmental Monitoring and Reporting Branch Ontario Ministry of the Environment For: Hamilton Harbour Remedial Action Plan Toxic Substances and Sediment Technical Team


2007 Field Season in the Hamilton Harbour Area of Concern PCB and PAH water monitoring undertaken by the Ontario Ministry of the Environment to support mass balance work by the Hamilton Harbour Remedial Action Plan (RAP) on PAH contamination at Randle Reef and PCB contamination in Windermere Arm Prepared by: Tanya Labencki Environmental Monitoring and Reporting Branch Ontario Ministry of the Environment For

:

Hamilton Harbour Remedial Action Plan Toxic Substances and Sediment Technical Team

First Published: December 2009 ISBN: 978-0-9810874-2-9 (Print Version) ISBN: 978-0-9810874-3-6 (Online Version)

For more information contact: Hamilton Harbour Remedial Action Plan Office P.O. Box 5050 867 Lakeshore Road Burlington, Ontario, L7R 4A6 Canada Tel. 905-336-6279 Fax 905-336-4906 Email RAPOffice@ec.gc.ca Website: www.hamiltonharbour.ca/rap


2007 Field Season in Hamilton Harbour

Executive Summary Hamilton Harbour has been identified as an area of concern (AOC) on the Great Lakes due to several beneficial use impairments (BUIs), several of which are related to contaminated sediment “hotspots” within the Harbour. One such sediment “hotspot” – Randle Reef – is contaminated primarily with polycyclic aromatic hydrocarbons (PAHs), compounds which are known to have negative biological effects. A sediment management strategy is in place to isolate these sediments in an engineered containment facility (ECF); however, further work to characterize ongoing and background levels of PAH to and within the Harbour was warranted to manage expectations on resulting PAH levels in Harbour waters following remedial actions. Another sediment “hotspot” – Windermere Arm – is contaminated primarily with polychlorinated biphenyls (PCBs), compounds responsible for driving the BUI Restrictions on Fish and Wildlife Consumption in Hamilton Harbour. Further work to characterize PCB loads to the Harbour and ambient PCB levels in Harbour waters was warranted as part of the process to develop a PCB management strategy for Hamilton Harbour. The nature of the environmental issues at each of these “hotspots” are mutually exclusive but were examined as part of a common field program in 2007 to maximize sampling efficiency. Whole water samples were collected for six events between March and September 2007 at three tributaries (Red Hill Creek, Indian Creek, Grindstone Creek), the Desjardins Canal and at the Woodward Ave and Skyway waste water treatment plants (WWTPs). Events included spring freshet, base flow, and five different storm events. Depth-integrated water samples were also taken from Hamilton Harbour centre station and mid-Windermere Arm on three occasions between April and July 2007. These sampling episodes were pre-planned and did not correspond to the event-based sampling events. All water samples were collected in duplicate, were whole-water samples and were analyzed for total suspended solids (TSS), PAHs (15 compounds) and PCBs (82 congeners). One field blank was analyzed for each sampling day for quality assurance/quality control (QA/QC) purposes. In addition to the water sampling conducted during 2007, a sediment grab sample was collected August 2007 from the mouth of Grindstone Creek and was analyzed for PCBs (55 congeners) and total organic carbon (TOC). Additionally, sampling for young-of-the-year (YOY) fish was attempted in 2007 but forfeited due to a lack of fish found at Harbour sampling locations. Results of the 2007 field season were analyzed separately for PAHs and PCBs; TSS results were used to support interpretation of PAH and PCB datasets. Only limited data analysis could be conducted on the PAH dataset as many of the PAH compounds analyzed were below the method detection limit. Nonetheless, for the event-based sampling conducted during 2007, the spatial trend in median total PAH concentration was: Red Hill Creek ≈ Indian Creek > Woodward Ave WWTP > Grindstone Creek ≈ Hamilton Harbour Remedial Action Plan

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Desjardins Canal > Skyway WWTP. Intra-annual temporal variability (i.e. betweenevent variability) was high at each station, and no one event demonstrated consistently high PAH concentrations across the stations studied. PAH compound profiles were similar between stations with fluoranthene, pyrene and phenanthrene as the most prevalent PAH compounds among stations and events. The ambient in-Harbour water sampling demonstrated consistently higher PAH concentrations in mid-Windermere Arm relative to Hamilton Harbour centre station and PAH concentrations in mid-Windermere Arm were generally lower than those measured in Red Hill and Indian Creeks demonstrating a decreasing PAH concentration gradient from the watersheds, to Windermere Arm, to the Harbour. Results demonstrated the importance of urban runoff as a source of PAHs to Hamilton Harbour; PAH loads from the watersheds will continue to be delivered to the Harbour following clean-up of PAHcontaminated sediment at Randle Reef. Data analysis on the PCB dataset revealed differences in trends relative to those found for PAHs. For the event-based sampling conducted during 2007, the spatial trend in median total PCB concentration was: Woodward Ave WWTP > Desjardins Canal > Red Hill Creek > Skyway WWTP ≈ Indian Creek > Grindstone Creek. The higher than expected PCB concentrations measured at the Desjardins Canal may have been due to backflow of Harbour water towards Cootes Paradise; however, data were insufficient to rule out an uncharacterized source of PCBs to Cootes Paradise. Temporal variability of the 2007 event-based dataset was highest at the Woodward Ave WWTP and lowest at the Desjardins Canal and the Skyway WWTP, where PCB concentrations varied little between the event types sampled. PCB concentrations were highest at the Woodward Ave WWTP following the largest storm event, likely due to the input of PCBs from stormwater, and PCB concentrations were highest in the tributaries during spring freshet, likely due to high TSS concentrations. PCB concentrations in the tributaries were lowest during baseflow. Total PCB concentrations and temporal trends differed greatly between the Woodward Ave and Skyway WWTPs, suggesting that the combined sewer system in Hamilton plays a role in the greater conveyance of PCBs to the Harbour relative to the separated sewer system in Burlington. PCB congener profiles showed enrichment of less-chlorinated congeners in final effluent from both WWTPs which did not clearly match Aroclor profiles (or one another); explanatory factors remain complex although a possible driver is PCB dechlorination at the plants. In contrast to these profiles, water samples from the tributaries and the Desjardins Canal generally showed a similarity to a typical Aroclor 1254/1260 profile, particularly when TSS concentrations were elevated. The ambient in-Harbour PCB sampling demonstrated consistently higher PCB concentrations in mid-Windermere Arm relative to Hamilton Harbour centre station; temporal variability was also higher at mid-Windermere Arm relative to Hamilton harbour centre station. While this concentration gradient was in-line with expectations given historical PCB contamination in Windermere Arm, unexpected was the finding that PCB concentrations were generally greater from the ambient, in-Harbour dataset Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

relative to samples collected from the WWTPs and tributaries. Given this “reverse� gradient (i.e. PCB concentrations in receiving water body > watersheds), and that PCB concentrations in the Harbour were consistently well above the provincial water quality objective (PWQO) and background concentrations, PCB concentrations in the waters of Hamilton Harbour remain of concern. PCB loading estimates based on the 2007 dataset were consistent with previous PCB loading estimates, and demonstrated that for the sources examined, PCB load is generally reflective of flow volume. As such, for the six sources examined in 2007, the Woodward Ave WWTP was estimated to have the largest PCB load to Hamilton Harbour. While the WWTPs and tributaries contribute PCB loads to the Harbour, results indicate that the influent sources characterized in 2007 did not have PCB concentrations high enough nor the appropriate PCB congener signatures to adequately explain the elevated in-Harbour PCB concentrations assuming the 2007 dataset is representative of these sources, a caveat to the limited sampling performed. Potential remaining PCB sources to the Harbour include resuspension of PCB-contaminated sediment, event-based contributions such as combined sewer overflows (CSOs), or other, uncharacterized sources. Data collected during 2007 suggest that resuspension and event-based contributions could both be plausible explanations for elevated PCB concentrations in the Harbour, yet data remain insufficient to determine the relative role that each of these potential sources play in the complex PCB dynamics of Hamilton Harbour. Finally, several recommendations for follow-up work were formed, including: 1. Use of an analytical method with lower PAH compound detection limits (lower than PWQOs) should any further PAH analysis be required for Harbour waters; 2. A review of all available PAH data as well as a review of source apportionment work by Sofowote et al. (2008) to provide additional context regarding sediment and water column, interactions for PAHs; 3. Additional sampling to determine if there is an active, locally-controllable source of PCBs to Hamilton Harbour; 4. Additional sampling to determine if resuspension of PCB-contaminated sediments is a primary driver behind elevated PCB water concentrations in Hamilton Harbour; 5. Additional sampling to determine if elevated PCB concentrations measured at the Desjardins Canal during 2007 are likely due to back-flow of Hamilton Harbour waters, or if elevated PCB concentrations are due to an uncharacterized PCB source to Cootes Paradise; 6. YOY fish sampling should be re-attempted at the locations sampled in 2006 (Grindstone Creek, Canada Centre for Inland Waters (CCIW)).

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Acknowledgements Many people were instrumental to the completion of work described herein, and their assistance and cooperation is much appreciated. Many thanks to Dave Supper of the Great Lakes Unit (Ministry of the Environment (MOE)) for collection of samples from the tributaries and wastewater treatment plants (WWTPs). Assistance by Greg Hobson, Wendy Page, Lance Boyce, and Mike Beaudoin, also of the Great Lakes Unit (MOE), is also appreciated for the collection of samples from Hamilton Harbour. Additionally, thanks are extended to Eric Reiner and colleagues of the Dioxins and Toxics Organics Unit of the Laboratory Services Branch (MOE) for analytical assistance, to Duncan Boyd of the Great Lakes Unit for ongoing assistance with project planning and interpretation and to Cheriene Vieira for her review and insightful comments on this report. Assistance from individuals external to the MOE was also key to completion of the 2007 field season, including support provided by Mukesh Patel of the Regional Municipality of Halton for sampling at the Skyway WWTP, and Khalid Mehmood of the City of Hamilton for sampling at the Woodward Ave WWTP. The Hamilton Harbour Remedial Action Plan (HH RAP) Office as well as the HH RAP Toxic Substances and Sediment Technical Team are also acknowledged for their support.

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Table of Contents Executive Summary ........................................................................................................iii Acknowledgements .........................................................................................................vi Table of Contents ...........................................................................................................vii List of Figures..................................................................................................................ix List of Tables...................................................................................................................xi Table of Acronyms .........................................................................................................xii 1. Background ................................................................................................................ 1 1.1 Randle Reef and PAH-Related Issues .................................................................. 1 1.2 Windermere Arm and PCB-Related Issues ........................................................... 4 1.3 2007 Field Season Objectives............................................................................... 6 1.4 2007 Field Season Limitations .............................................................................. 7 2. Methods ...................................................................................................................... 9 2.1 Event-based water sampling conducted at the wastewater treatment plants (WWTPs) and tributaries .............................................................................................. 9 2.2 In-Harbour water sampling ................................................................................... 12 2.3 YOY fish sampling................................................................................................ 14 2.4 Sediment Sampling .............................................................................................. 14 3. Results and Discussion of Event-based Water Sampling Conducted at the Wastewater Treatment Plants (WWTPs) and Tributaries.............................................. 16 3.1 Total suspended solids (TSS) .............................................................................. 16 3.2 Polycyclic Aromatic Hydrocarbons (PAHs)........................................................... 19 3.2.1 Total PAH Concentrations .............................................................................. 19 3.2.2 PAH Loadings ................................................................................................ 23 3.2.3 PAH Compound Profiles................................................................................. 25 3.3 Polychlorinated biphenyls (PCBs) ........................................................................ 32 3.3.1 Total PCB Concentrations .............................................................................. 32 3.3.2 PCB Loadings ................................................................................................ 43 3.3.3 PCB Congener Profiles .................................................................................. 48 4. Results and Discussion of In-Harbour Water Sampling............................................. 60 4.1 Total Suspended Solids (TSS) ............................................................................. 60 4.2 Polycyclic Aromatic Hydrocarbons (PAHs)........................................................... 62 4.2.1 Total PAH Concentrations .............................................................................. 62 4.2.2 PAH Compound Profiles................................................................................. 65 4.3 Polychlorinated Biphenyls (PCBs)........................................................................ 68 4.3.1 Total PCB Concentrations .............................................................................. 68 4.3.2 PCB Congener Profiles .................................................................................. 75 5. Results and Discussion of Sediment Sampling ......................................................... 82 6. Conclusions............................................................................................................... 82 6.1 PAHs and Randle Reef ........................................................................................ 83 6.2 PCBs and Windermere Arm ................................................................................. 84 7. Recommendations .................................................................................................... 87 8. References................................................................................................................ 90 Hamilton Harbour Remedial Action Plan

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Appendix I: March – September 2007 weather conditions in Hamilton. ........................ 94 Appendix II: Grindstone Creek hydrographs for 2007 ................................................. 101 Appendix III: Field photographs taken during 2007 ..................................................... 102 Appendix IV: PAH, PCB and TSS Analytical Methods ................................................ 116

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List of Figures Figure 1: Map depicting locations of Randle Reef and Windermere Arm within Hamilton Harbour ........................................................................................................................... 1 Figure 2: Fluorometer profiling of Hamilton Harbour water conducted in May and August 2000 by the Ministry of the Environment (MOE) whereby ultraviolet (UV) fluorescence demonstrates relative PAH concentration in the water column. ...................................... 3 Figure 3: Temporal trends of mean PCB concentrations in young-of-the-year (YOY) fish sampled from Hamilton Harbour and western Lake Ontario............................................ 5 Figure 4: Map of event-based sampling locations for 2007 field season in Hamilton Harbour ......................................................................................................................... 10 Figure 5: Map of in-Harbour sampling locations for 2007 field season in Hamilton Harbour ......................................................................................................................... 12 Figure 6: Map of Grindstone Creek 2007 sediment sampling location .......................... 15 Figure 7: Sediment sample collected from the mouth of Grindstone Creek (station 09 15 0002) on August 8, 2007. .............................................................................................. 15 Figure 8: Mean replicate TSS concentration measured at six stations during summer 2007 event-based sampling. ......................................................................................... 16 Figure 9: Replicate mean total Σ15PAH concentrations (ng/L) measured at six locations during six events monitored in Hamilton Harbour during 2007...................................... 21 Figure 10: Correlations between total Σ15PAH and TSS concentrations for event-based sampling conducted at six stations during 2007............................................................ 22 Figure 11: PAH profiles for event-based samples collected from Woodward Ave WWTP, Red Hill Creek, Indian Creek, Grindstone Creek and the Desjardins Canal during summer 2007. ............................................................................................................... 26 Figure 12: Replicate mean total PCB concentrations (ng/L) measured at six locations during six events monitored in Hamilton Harbour during 2007...................................... 34 Figure 13: Correlation between total PCB concentrations in travel blanks and total PCB concentrations in samples where travel blanks were collected. .................................... 34 Figure 14: Correlation between total PCB and TSS concentrations at six stations for six events sampled in Hamilton Harbour during 2007. ....................................................... 36 Figure 15: Previous and 2007 update of PCB loading estimates for input sources to Hamilton Harbour. ......................................................................................................... 45 Figure 16: Temporal trends of estimated PCB loads to Hamilton Harbour.................... 46 Figure 17: PCB Congener profiles for WWTPs, tributaries, Desjardins Canal, travel blanks and Aroclor mixtures. ......................................................................................... 50 Figure 18: Principle Component Analysis (PCA) plots for WWTPs and tributaries relative to Aroclor mixtures during each event monitored in 2007. ............................................ 53 Figure 19: Principle Component Analysis (PCA) plots for each WWTP and tributary station monitored demonstrating temporal variability in PCB signature during 2007..... 57 Figure 20: Mean replicate TSS concentrations measured at Hamilton Harbour centre station and mid-Windermere Arm on three sampling occasions during summer 2007.. 60 Figure 21: Minimum mean total Σ15PAH concentrations (ng/L) measured at two inHarbour locations on three occasions during 2007. ...................................................... 63 Hamilton Harbour Remedial Action Plan

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Figure 22: PAH compound profiles of water collected from Hamilton Harbour centre station and mid-Windermere Arm on three sampling occasions during summer 2007.. 65 Figure 23: Replicate mean total ÎŁ82PCB concentrations (ng/L) measured at two inHarbour locations on three occasions during 2007. ...................................................... 69 Figure 24: Mean PCB concentrations measured at all Hamilton Harbour stations monitored during 2007. ................................................................................................. 73 Figure 25: PCB congener profiles for Centre Station, Mid-Windermere Arm, travel blanks and Aroclor mixtures. ......................................................................................... 76 Figure 26: PCB congener profiles for Centre Station and Mid-Windermere Arm. ......... 77 Figure 27: Principle component analysis (PCA) plot for PCB congener patterns observed at stations 258 and 352 during three 2007 surveys. ...................................... 78 Figure 28: PCB congener profiles for water and sediment samples collected from station 352 (mid-Windermere Arm) in 2007 and 2003, respectively. ........................................ 79 Figure 29: Principle Component Analysis (PCA) plot for water samples collected during 2007 from mid-Windermere Arm (station 352), Woodward Ave WWTP (station 900030001), Red Hill Creek (station 900150007) and also for surface sediment samples collected during 2003 at mid-Windermere Arm (station 352). ....................................... 80 Figure 30: Principle Component Analysis (PCA) plot for water samples collected during 2007 from centre station (station 258) and the Desjardins Canal (station 900150008). 81

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List of Tables Table 1: Event-based sampling locations for 2007 field season in Hamilton Harbour..... 9 Table 2: Event-based sampling dates and weather conditions for the 2007 field season in Hamilton Harbour ...................................................................................................... 10 Table 3: Event-based travel blanks collected during the 2007 field season .................. 11 Table 4: In-Harbour sampling locations for 2007 field season in Hamilton Harbour...... 12 Table 5: In-Harbour sampling dates and weather conditions for the 2007 field season in Hamilton harbour........................................................................................................... 13 Table 6: In-Harbour travel blanks collected during the 2007 field season ..................... 13 Table 7: Replicate mean TSS concentrations (mg/L) for event-based sampling conducted at the WWTPs and tributaries during 2007. ................................................. 17 Table 8: Replicate mean total Σ15PAH concentrations (ng/L) for event-based sampling conducted at the WWTPs and tributaries during 2007. ................................................. 20 Table 9: Estimated low, base case and high PAH loads to Hamilton Harbour from six input sources................................................................................................................. 24 Table 10: Provincial Water Quality Objectives (PWQOs), Canadian Water Quality Guidelines (CWQGs) and detection limits for 15 PAH compounds analyzed................ 28 Table 11: Mean fluoranthene, pyrene and phenanthrene concentrations (ng/L) in Red Hill Creek, Indian Creek and Grindstone Creek relative to concentrations measured during 1991-1992 in six Toronto rivers (Boyd et al., 1999)............................................ 31 Table 12: Replicate mean total Σ82PCB concentrations (ng/L) for event-based sampling conducted at the WWTPs and tributaries during 2007. ................................................. 33 Table 13: Mean PCB concentrations in Red Hill Creek, Indian Creek and Grindstone Creek relative to mean 1991-1992 Toronto tributary PCB concentrations (Boyd et al., 1999) ............................................................................................................................. 43 Table 14: Estimated low, base case and high PCB loads to Hamilton Harbour from six input sources................................................................................................................. 44 Table 15: Replicate mean TSS concentrations (mg/L) for in-Harbour sampling conducted during 2007.................................................................................................. 61 Table 16: Replicate mean total Σ15PAH concentrations (ng/L) for in-Harbour sampling conducted during 2007.................................................................................................. 62 Table 17: Replicate mean total Σ82PCB concentrations (ng/L) for in-Harbour sampling conducted during 2007.................................................................................................. 68 Table 18: Theoretical PCB suspended sediment concentrations at centre station and mid-Windermere Arm based on measured PCB and TSS concentrations during three surveys during 2007. ..................................................................................................... 71

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Table of Acronyms AOC BUI CCIW CCME CSO CV CWQG ECF HH RAP LEL MLD MOE MOEE PAH PCA PCB PEL PSQG PWQO QA/QC TOC TSS UV WWTP YOY

Area of Concern Beneficial Use Impairment Canada Centre for Inland Waters Canadian Council of Ministers of the Environment Combined sewer overflow Coefficient of variation Canadian Water Quality Guideline Engineered containment facility Hamilton Harbour Remedial Action Plan Lowest effect level Megalitres per day (or millions of litres per day) Ministry of the Environment Ministry of the Environment and Energy Polycyclic aromatic hydrocarbon Principle component analysis Polychlorinated biphenyl Probable effect level Provincial Sediment Quality Guideline Provincial Water Quality Objective Quality assurance/quality control Total organic carbon Total suspended solids Ultra violet Waste water treatment plant Young-of-the-year

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1. Background Hamilton Harbour has been identified as an area of concern (AOC) on the Great Lakes due to several beneficial use impairments (BUIs). Contaminated sediment in the Harbour is a likely driver for several BUIs, including: Restrictions on Fish and Wildlife Consumption, Fish Tumours or Other Deformities, and Degradation of Benthos, subsequently resulting in Degraded Fish and Wildlife Populations. Although levels of organic contaminants and metals are generally elevated throughout the Harbour, there are specific “hotspot” locations in the Harbour that have been examined more closely due to more specific ties with the BUIs mentioned. These “hotspot” locations include Randle Reef, and Windermere Arm (Figure 1). The nature of the environmental issues at these “hotspots” are mutually exclusive but were examined as part of a common field program in 2007 to maximize sampling efficiency.

Figure 1: Map depicting locations of Randle Reef and Windermere Arm within Hamilton Harbour

1.1 Randle Reef and PAH-Related Issues Randle Reef is located along the southern industrial shore of Hamilton Harbour (Figure 1) and is well known for its coal-tar deposits and highly elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) in sediment. Numerous sediment assays conducted over the past few decades have established that sediments in this part of the Harbour are toxic using both acute and chronic exposures and lethal and sublethal endpoints. The PAH contamination at Randle Reef is a driver for BUIs, and as such, a sediment management strategy has been developed to build an engineered containment facility (ECF). The ECF will sequester the most contaminated sediments in Hamilton Harbour Remedial Action Plan

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situ, and other highly contaminated sediments adjacent to the ECF will be dredged and placed into the facility for containment. While this plan will result in removal of fish and benthos exposure to contaminated sediments at Randle Reef, it remains disconnected from the issue of ongoing PAH loadings to the Harbour from urban background sources (e.g. urban runoff) and the potential for fish and benthos exposure to these additional sources of PAHs in the water column (i.e. pelagic exposure). The spatial concentration gradients of PAHs in Hamilton Harbour differ greatly between patterns observed in surface sediment relative to that in the water column. For surface sediment, concentrations of PAHs in Hamilton Harbour are highest at Randle Reef as demonstrated through Harbour-wide sediment surveys such as Milani and Grapentine (2006). For the water column, concentrations of PAHs are highest in Windermere Arm as demonstrated through Harbour-wide water quality surveys such as that conducted in May and August 2000 by the MOE (Figure 2). These spatial patterns are important for evaluating potential biological impacts of PAHs in Hamilton Harbour. Due to rapid PAH metabolization, PAHs are not biomagnified in the food web meaning pelagic exposure may be a primary exposure route to fish for PAHs relative to exposure obtained through contaminated sediments.

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Figure 2: Fluorometer profiling of Hamilton Harbour water conducted in May and August 2000 by the Ministry of the Environment (MOE) whereby ultraviolet (UV) fluorescence demonstrates relative PAH concentration in the water column. Notes: Maps produced by T. Howell (MOE) and absolute PAH water concentrations at points indicated were analyzed by C. Marvin (Environment Canada).

While Randle Reef is a source of PAHs to the water column due to sediment resuspension and chemical partitioning, a portion of PAHs in water is thought to be coming into the Harbour from external sources such as urban runoff, much of which enters the Harbour via Windermere Arm. Externally-sourced PAHs in the water column will not diminish with clean-up at Randle Reef. An understanding of the relative contribution from external sources is key to evaluating the success of the clean-up at Randle Reef. A PAH mass balance may assist with this evaluation and could demonstrate what portion of PAHs in the open Harbour are due to external sources relative to PAHs originating from contaminated sediment at Randle Reef. Having ongoing, external PAH sources is not at odds with clean-up at Randle Reef as: 1) any results from a PAH mass balance will not change Randle Reef contaminated sediments being responsible for the BUI degradation of benthos; and 2) to an extent unknown at this time, PAH pelagic exposure to fish would be reduced to levels comparable with other urban areas following Randle Reef clean-up given PAHs sourced from resuspension and partitioning of historically contaminated sediment would decline. Results from PAH sampling in Hamilton Harbour is of interest to the Hamilton Harbour Remedial Action Plan (HH RAP), including the Randle Reef remediation project managers (West Central Region, MOE; Environment Canada) and as well as members of the HH RAP “Randle Reef Indicators of Success� team. This team is led with evaluating relevant conditions in the Harbour prior to, during, and post ECF construction - an important process in determining the full impacts of the Randle Reef clean-up project on the Harbour. Part of this process also includes managing expectations of Hamilton Harbour Remedial Action Plan

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remediation at Randle Reef so that predicted outcomes post-remediation are based on the best science outlining what is realistically achievable for the Harbour given factors external to issues specific to Randle Reef. As Hamilton Harbour receives urban runoff and other background sources of PAHs, dredging contaminated sediment from Randle Reef is not expected to eliminate PAH inputs to the Harbour, and hence, PAH exposure issues in Hamilton Harbour. Source apportionment of PAHs in Hamilton Harbour has recently been addressed by researchers from McMaster University using statistical analysis of PAH profiles (Sofowote et al., 2008). A review of this work should accompany review of the data described herein to gain additional context and interpretation of the MOE’s 2007 sampling program.

1.2 Windermere Arm and PCB-Related Issues Windermere Arm is an area of Hamilton Harbour located in the southeast corner of the Harbour (Figure 1) and is well known for its highly elevated concentrations of polychlorinated biphenyls (PCBs) in sediment. Sediment cores in Windermere Arm were collected in 2003 by the Ontario Ministry of the Environment (MOE) in collaboration with Environment Canada, as a follow-up to cores collected in 2001 by Environment Canada (Zeman and Patterson, 2003). The 2003 sediment coring results showed a maximum total PCB concentration of 28,000 ng/g at a depth of 40 – 50 cm, and a Windermere Arm area-averaged surficial (top 10 cm) sediment PCB concentration of 1,270 ng/g (Labencki, 2008). These concentrations are well above the Canadian Council of Ministers of the Environment (CCME) (2001) Probable Effect Level (PEL) of 277 ng/g and the provincial Lowest Effect Level (LEL) of 70 ng/g (MOE, 1993). The elevated PCB concentrations are of particular significance to the Hamilton Harbour AOC as they are the primary driver for the BUI Restrictions on Fish and Wildlife Consumption. As such, there is a need to assess the PCB-contaminated sediments in the Harbour due to the potential for bioaccumulation and biomagnification of locallysourced PCBs resulting in PCB concentrations in fish tissues above relevant consumption guidelines. PCB concentrations in young-of-the-year (YOY) fish sampled from the Harbour and western Lake Ontario (Figure 3) demonstrated: a) higher PCB concentrations in Hamilton Harbour YOY fish sampled in 2006 relative to previous years; b) higher PCB concentrations in the Harbour relative to other Lake Ontario nearshore locations; and c) biological uptake of locally-sourced PCBs is occurring in Hamilton Harbour as YOY fish have a small home range and known length of exposure. Understanding the connections between locally-sourced PCB in sediment and biota is related to issues in Windermere Arm as the highest PCB concentrations in sediment are observed in this area of the Harbour (Labencki, 2008).

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YOY PCB concentrations in Hamilton Harbour 1400 1200

Spottail Shiner Emerald Shiner

1000

ng/g

800 600 400 200 0 1991 1994 1999 2000 2003 2006 CCIW CCIW CCIW CCIW CCIW CCIW

1400 1200

1991 1999 BGC BYC

1991 WC

2006 2006 GC GC

YOY PCB concentrations in Western Lake Ontario Spottail Shiner Emerald Shiner

ng/g

1000 800 600 400 200 0 2000 2003 2006 1997 Burlington Burlington Burlington Oakville Beach Beach Beach Harbour

2000 Bronte Creek

2000 Mimico Creek mouth

2000 Mimico Creek mouth

2003 Port 2003 Port Dalhousie Dalhousie

Figure 3: Temporal trends of mean PCB concentrations in young-of-the-year (YOY) fish sampled from Hamilton Harbour and western Lake Ontario. Notes: Error bars represent plus and minus one standard deviation of annual datasets.

As a step towards developing a sediment management strategy for PCB contaminated sediment in Windermere Arm to ultimately address the BUI, a PCB massbalance model was initiated by researchers at the University of Toronto (Gandhi and Diamond, 2005). The goals of the mass-balance model were to discern the role of historical PCB contamination versus current loadings to fish exposure pathways; and to determine if Windermere Arm is a source or sink of PCB contaminated sediment in Hamilton Harbour. During development of the PCB mass-balance model, it became clear that contemporary PCB loadings to the Harbour were not well characterized, which translated to a large data gap in efforts to address the related BUI. The estimated PCB Hamilton Harbour Remedial Action Plan

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loadings to the Harbour which existed were based on PCB suspended sediment concentrations in Harbour influent (MOE data from 1988-1991; Boyd, 2001) and suspended sediment loads to the Harbour (HH RAP, 2004). These data that were available indicated basecase estimated loadings of 0.85 kg/year to Windermere Arm (0.77 kg/year from Woodward Ave waste water treatment plant (WWTP) + <0.073 kg/year from Red Hill Creek), with the largest overall Harbour loading attributable to Woodward Avenue WWTP; these loading estimates are shown in Labencki (2008). As the spatial distribution and relatively small magnitude of loadings were not consistent with preliminary output from the University of Toronto PCB mass-balance model, and data used to estimate loadings were over 15 years old and based on two separate, unrelated datasets, gathering updated influent data to generate updated Harbour PCB loadings was determined a priority in addressing this data gap. Along similar lines, the University of Toronto PCB mass-balance model was found to be sensitive to the PCB water concentration in the centre of the Harbour and Windermere Arm; as such, obtaining updated ambient PCB water concentrations was also determined a priority, and would help to reduce uncertainty in the PCB mass-balance model. Results from PCB sampling in Hamilton Harbour is of interest to the HH RAP, including the members of the HH RAP “Toxic Substances and Sediment Technical Team” and the PCB mass-balance researchers at the University of Toronto. The 2007 PCB sampling program will assist in determining what if any remedial actions are required to address the BUI Restrictions on Fish and Wildlife Consumption, so that there are no restrictions on the consumption of fish from the Harbour attributable to local sources.

1.3 2007 Field Season Objectives The primary objective of the 2007 field season sampling was to gather data to address identified data gaps and uncertainties in PAH and PCB sources and ambient concentrations. These data were also collected to refine PCB loading estimates to Hamilton Harbour and also to provide further lines-of-evidence on the nature of PAH and PCB contamination in the waters of Hamilton Harbour. Data that were gathered were collected to answer the following specific questions: • • • •

What is the current estimated annual loading to the Harbour of PAHs and PCBs from Woodward Avenue WWTP, Skyway WWTP, Red Hill Creek, Indian Creek, Grindstone Creek, Cootes Paradise? What are typical ambient PAH and PCB concentrations and profiles in the centre of Hamilton Harbour and in Windermere Arm? As investigated through PCB congener profile analysis or other methods, is there any evidence of potential PCB anomalies in Hamilton Harbour influent sources that warrant follow-up action? Do concentrations of PCBs in YOY fish support recent increased PCB exposure in Hamilton Harbour?

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Data collected in 2007 also addresses concerns which have been expressed by the HH RAP in regard to the need to demonstrate due diligence and assess whether there are any remaining active PCB sources to the Harbour. Several reports have recommended that potential sources of PCBs be fully investigated. For example, in their full review on the chemical contamination of Hamilton Harbour, Harlow and Hodson (1988) recommended research to “[i]dentify all sources of PCBs” (Harlow and Hodson, 1988, p.75). Also, the HH RAP Stage 1 Report stated that: PCBs in the water column require more thorough investigation in conjunction with analyses of sediments, rainfall, and biota to ensure that all possible remedial actions have been taken to eliminate local sources. Initial results (Fox, personal communication) indicate that PCBs in the Harbour are older, weathered components which have not been recently released to the environment (HH RAP, 1992a, p.171). In addition, the 1998 Status Report stated that “fish consumption advisories are based on PCBs and it is assumed there are no active sources, but there has been no full investigation to confirm this assumption” (HH RAP, 1998, p.56). Similarly, “for substances which give rise to fish consumption advisories…no comprehensive investigation has been taken to determine whether local sources exist and may be controllable (HH RAP, 1998, p.57). Although a Harbour-wide investigation of PCBs in Harbour inflows was undertaken from 1988-1991 by the MOE (Boyd, 2001), results are dated and only suspended sediment were analyzed, rather than whole water samples. The 2007 monitoring at select Harbour inflow points helps to close the loop on whether there is any evidence of active, locally-controllable sources of PCBs to Hamilton Harbour.

1.4 2007 Field Season Limitations Limitations of the 2007 field season sampling and data analysis were identified a priori; these project limitations were acknowledged to assist with data interpretation and included the following: •

• •

Sampling at combined sewer overflows (CSOs) was not conducted due to challenging logistics, the high number of CSOs in the City of Hamilton, and the dependence on extreme weather conditions (i.e. intense rainfall). As has been discussed with partners, any future PCB sampling at CSOs is to be led by the City of Hamilton. Variability of flow and concentrations of PAHs and PCBs in harbour influent water translates to high sampling variability (and hence loading variability) and the potential to miss peak loading periods. Concentrations of PAHs and PCBs in Woodward Avenue WWTP and Skyway WWTP influent will not be sampled due to difficulty in obtaining these samples. The utility of these data are also limited in terms of the mass-balance estimates as any PAHs and PCBs removed by water treatment processes are not part of the loadings

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â&#x20AC;˘

â&#x20AC;˘

to the Harbour; a regional PAH and PCB mass balance and loadings of PAHs and PCBs in sewage sludge are beyond the scope of this project. Sampling at the Desjardins Canal (at the Fishway) as a means to integrate contaminant loads to Hamilton Harbour from several sources to Cootes Paradise will likely be complicated due to the ebb and flow nature of water flows at this location (T. Theysmeyer, 2007, pers. comm.). Hamilton Harbour water often flows into Cootes (including Seiche events) meaning samples taken at the Desjardins Canal during such time periods would reflect Harbour water and not loadings from Cootes Paradise. However, as it is generally accepted that Hamilton Harbour is more contaminated with PCBs relative to Cootes Paradise, calculated loads from Cootes Paradise will be conservative in that if anything, loadings will be overestimated rather than underestimated from Cootes Paradise due to the strong influence of the Harbour on samples taken at this location. If flow is into Cootes Paradise from the Harbour, one can assume the net loading of PCBs to the Harbour at that instant is 0. Flow direction at the Desjardins Canal will be noted at time of sampling. Sampling PCB concentrations in Spencer and Chedoke Creeks to estimate PCB loads from Cootes Paradise is not recommended as any PCB loads from these streams may not be transported out to the Harbour; the focus remains on a Hamilton Harbour mass-balance and not a Cootes Paradise mass-balance. Flow data for the creeks are lacking (required to calculate loadings as load = concentration * flow). As mentioned above, flow at the fishway is unknown; Water Survey of Canada has a gauging station on Grindstone Creek at Aldershot, but the gauging station at Red Hill Creek was discontinued in 2003 due to expressway construction and no gauging station was ever installed at Indian Creek. Flow data for the WWTPs are readily available from plant operators.

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2007 Field Season in Hamilton Harbour

2. Methods 2.1 Event-based water sampling conducted at the wastewater treatment plants (WWTPs) and tributaries Event-based water sampling was conducted on six occasions between March 14, 2007 and September 28, 2007 at Woodward Ave WWTP, Skyway WWTP, Red Hill Creek, Indian Creek, Grindstone Creek, and the Desjardins Canal (Table 1; Figure 4). Events targeted for sampling included: 1) spring freshet; 2) small rain event, (5 – 10 mm); 3) large rain event (10 - 25 mm); 4) extreme rain event (25+ mm); and 5) baseflow. Actual sample collection dates and antecedent weather conditions are shown in Table 2; a full listing of weather conditions for the 2007 field season is included in Appendix I, hydrographs for Grindstone Creek for summer 2007 are included in Appendix II, and field photographs taken during 2007 are included in Appendix III . The WWTPs were monitored on September 28th rather than the 27th (when tributaries sampled) to allow water from the event to be captured in the sampled final effluent as it takes approximately 24 hours for water to pass through the WWTP system. Table 1: Event-based sampling locations for 2007 field season in Hamilton Harbour Station Description Station Latitude Longitude Code Woodward Avenue WWTP Final 09 03 0001 43° 15’ 09.1” N 79° 46’ 12.8” W Effluent Skyway WWTP Final Effluent 09 03 0002 43° 18’ 39.9” N 79° 48’ 05.1” W Red Hill Creek (upstream of 09 15 0007 43° 14’ 53.1” N 79° 46’ 03.0” W Woodward) Indian Creek 09 15 0003 43° 18’ 56.0” N 79° 48’ 38.0” W Grindstone Creek (at Unsworth 09 15 0009 43° 18’ 01.6” N 79° 52’ 07.7” W Ave., Water Survey of Canada flow hut) Desjardins Canal (east end, east 09 15 0008 43° 16’ 45.6” N 79° 53’ 33.3” W of fishway)

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2007 Field Season in Hamilton Harbour

Figure 4: Map of event-based sampling locations for 2007 field season in Hamilton Harbour Table 2: Event-based sampling dates and weather conditions for the 2007 field season in Hamilton Harbour Sampling Date Stations Sampled Event-based Antecedent description weather conditions1 March 14, 2007 All stations in Table 1 Spring freshet April 27, 2007 All stations in Table 1, Large rain April 25 (1.2 mm) + except for Woodward Ave event Apr 26 (14.2mm) + WWTP: unable to collect Apr 27 (3.0 mm) = sample due to technical 18.4 mm difficulties in sampling hut. May 9, 2007 All stations in Table 1 Baseflow 10 days of no rain August 8, 2007 All stations in Table 1 Small rain event August 7 (2.8 mm) September 11, All stations in Table 1 Large rain Sep 9 (9.4 mm) + 2007 event Sep 10 (0) + Sep 11 (5.8 mm) = 15.2 mm September 27, Tributaries in Table 1 Extreme rain Sep 26 (20.0 mm) + 2007 event Sep 27 (6.2 mm) = 26.2 mm September 28, WWTPs in Table 1 Extreme rain Sep 26 (20.0 mm) + 2007 event Sep 27 (6.2 mm) + Sep 28 (1.2 mm) = 27.4 mm Notes: 1 â&#x20AC;&#x201C; Antecedent weather conditions from Environment Canada (2008). See Appendix I.

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Two discrete, replicate whole water grab samples (sample type 011; matrix WS) were collected during each event and at all stations. Replicates were collected for quality assurance/quality control (QA/QC) purposes and to integrate both field and laboratory variability. Water samples at the WWTPs were collected using installed “inhouse” final effluent sampling pumps. At the Woodward Ave WWTP, water samples were collected using an ISCO 3700 sampling pump. Samples were a 50/50 composite mix from the “north” and “south” final effluent channels which were homogenized in a 4 L neoprene container supplied by the WWTP before being decanted into MOE sample containers. At the Skyway WWTP, water samples were collected using a Sigma 900 sampling pump and final effluent samples were pumped directly into MOE sample containers. Water samples from the tributaries were filled directly into MOE sample containers and were collected with an extendable, fibreglass sampling pole. Sample volume collected was dependent on parameter for analysis. Two 1L amber bottles (“3P”) were used to collect water samples for PCB analysis, one 1L amber bottle (“3P”) was used to collect water samples for PAH analysis, and one 500 mL (“PET”) bottle was used for total suspended solids (TSS) water samples. All sample containers were rinsed twice with sample water prior to sample collection, and the second rinse of the 1 L amber bottles (use for PCB and PAH analysis) was used to rinse and fill the PET bottles for TSS analysis. All water samples were submitted to the MOE Laboratory Services Branch in Etobicoke, Ontario for analysis of 82 PCB congeners, 15 PAH compounds and TSS. Laboratory methods used for analysis of PCBs, PAHs and TSS were MOE methods PCBC3459, PAH3435 and SS3188, respectively (Appendix IV). One travel blank (sample type 015) was collected per event (Table 3). Travel blank water was filled in the lab with distilled, deionized water prior to the field sampling. Once on a randomly selected station during each event, the travel blank bottle was opened for the duration of the sampling time on station. Travel blanks were analyzed for PCBs and PAHs only (no TSS analysis). Table 3: Event-based travel blanks collected during the 2007 field season Sampling Date Station at which travel blank conducted March 14, 2007 Woodward Avenue WWTP (09 03 0001) April 27, 2007 Skyway WWTP (09 03 0002) May 9, 2007 Woodward Avenue WWTP (09 03 0001) August 8, 2007 Woodward Avenue WWTP (09 03 0001) September 11, 2007 Woodward Avenue WWTP (09 03 0001) September 27, 2007 none September 28, 2007 Woodward Avenue WWTP (09 03 0001)

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2007 Field Season in Hamilton Harbour

2.2 In-Harbour water sampling In-Harbour water sampling was conducted on three occasions between April 2, 2007 and July 24, 2007 at Hamilton Harbour centre station and the centre of Windermere Arm (Table 4; Figure 5). The in-Harbour sampling was not event-based and sampling was pre-planned by the field staff in the Great Lakes Unit. Actual sample collection dates and antecedent weather conditions are shown in Table 5; a full listing of weather conditions for the 2007 field season is included in Appendix I. Table 4: In-Harbour sampling locations for 2007 field season in Hamilton Harbour Station Description Station Latitude Longitude Code Hamilton Harbour centre station 09 01 0258 43° 17’ 19.7” N 79° 50’ 10.5” W Mid-Windermere Arm 09 01 0352 43° 16’ 23.9” N 79° 47’ 20.5” W

Figure 5: Map of in-Harbour sampling locations for 2007 field season in Hamilton Harbour

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Table 5: In-Harbour sampling dates and weather conditions for the 2007 field season in Hamilton harbour Sampling Date Stations Sampled Antecedent weather conditions1 April 2, 2007 All stations in Table Mar 26: 17.6 mm rain; Mar 27-30: no rain; 4 Mar 31: trace; April 1: 8.8 mm rain; Apr 2: trace May 31, 2007 All stations in Table May 24: no rain; May 25: 1.8 mm; May 26: 4 trace; May 27: 7.2 mm rain; May 28-30: no rain; May 31: trace July 24, 2007 All stations in Table July 17-18: no rain; July 19: 5.6 mm rain; 4 July 20-22: no rain; July 23: 0.6 mm rain; July 24: trace Notes: 1 – Antecedent weather conditions from Environment Canada (2008)

Two discrete, replicate whole water samples (matrix WS) were collected during each survey and at both stations. Replicates were collected for QA/QC purposes and to integrate both field and laboratory variability. Water samples were depth-integrated (sample type 012) between the surface and ~1-2 m from bottom and were collected with a glug-glug sampler. Sample volume collected was dependent on parameter for analysis. Two 1L amber bottles (“3P”) were used to collect water samples for PCB analysis, one 1L amber bottle (“3P”) was used to collect water samples for PAH analysis, and one 500 mL (“PET”) bottle was used for TSS water samples. All sample containers were rinsed twice with sample water prior to sample collection, and the second rinse of the 1 L amber bottles (use for PCB and PAH analysis) was used to rinse and fill the PET bottles for TSS analysis. Water for PCB and PAH analysis was filled directly to MOE sample containers. All water samples were submitted to the MOE Laboratory Services Branch in Etobicoke, Ontario for analysis of 82 PCB congeners, 15 PAH compounds and TSS. Laboratory methods used for analysis of PCBs, PAHs and TSS were MOE methods PCBC3459, PAH3435 and SS3188, respectively (Appendix IV). One travel blank (sample type 015) was collected each sampling day (Table 6). Travel blank water was filled in the lab with distilled, deionized water prior to the field sampling. Once on a randomly selected station during each survey, the travel blank bottle was opened for the duration of the sampling time on station. Travel blanks were analyzed for PCBs and PAHs only (no TSS analysis). Table 6: In-Harbour travel blanks collected during the 2007 field season Sampling Date Station at which travel blank conducted April 2, 2007 Mid-Windermere Arm (09 01 0352) May 31, 2007 Hamilton Harbour centre station (09 01 0258) July 24, 2007 Hamilton Harbour centre station (09 01 0258)

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2007 Field Season in Hamilton Harbour

2.3 YOY fish sampling In response to elevated PCB concentrations in YOY fish sampled in 2006, resampling for YOY fish was attempted by the MOE’s Sport Fish and Biomonitoring Unit in fall 2007 at the same two locations sampled in 2006 (Grindstone Creek and Canada Centre for Inland Waters (CCIW) sampling location) plus a location at Bayfront Park (Hamilton public beach). However, no YOY fish were found at the Grindstone Creek and Bayfront Park locations and only 3 YOY fish (emerald shiners) were found at the CCIW sampling location in 2007. As these 3 fish did not meet the net minimum weight requirement for PCB samples, they were not submitted for analysis. As such, there are no Hamilton Harbour YOY fish results for 2007. Reasons for the inability to obtain samples of YOY fish remain unknown, however, it has been speculated that the low lake level in 2007 due to drought conditions may have played a role (S. Petro, 2008, pers. comm.). Also, field staff noted that the Grindstone Creek location was choked with cladophora during sampling attempts (S. Petro, 2008, pers. comm).

2.4 Sediment Sampling An opportunistic (unplanned) surface sediment grab sample (matrix SE) was collected at station 09 15 0002 (43.28972° N, 79.88556° W) at the mouth of Grindstone Creek (Figure 6) on August 8, 2007. The sample was collected in response to elevated PCB concentrations in YOY fish at the Grindstone Creek location during the 2006 season. The sediment sample was a composite of three grabs (sample type 55) from the surface to 5 cm depth, collected approximately 4 m from the shoreline. The sediment sample was homogenized with a stainless steel spoon in the field (Figure 7) and submitted to the MOE Laboratory Services Branch in Etobicoke, Ontario for analysis of PCB congeners (55 congeners) and total organic carbon (TOC). Laboratory methods used for analysis of PCBs and TOC were MOE methods PCBC3412 and ORGC3012, respectively (Appendix IV).

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2007 Field Season in Hamilton Harbour

Figure 6: Map of Grindstone Creek 2007 sediment sampling location

Figure 7: Sediment sample collected from the mouth of Grindstone Creek (station 09 15 0002) on August 8, 2007.

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2007 Field Season in Hamilton Harbour

3. Results and Discussion of Event-based Water Sampling Conducted at the Wastewater Treatment Plants (WWTPs) and Tributaries 3.1 Total suspended solids (TSS) Replicate mean TSS concentrations for the event-based sampling conducted at the WWTPs and tributaries are presented graphically in Figure 8, and summarized in Table 7. Variability within each set of replicate samples was generally low. The coefficient of variation (CV) was calculated for each replicate set of TSS concentrations (CV = standard deviation/mean), with a CV of zero signifying no difference between replicate samples. For the 2007 WWTP and tributary dataset, CVs ranged from 0 (multiple stations) to 0.34 (Indian Creek, May 9, 2007; replicates: 5.1 mg/L, 3.1 mg/L) and had an overall median CV of 0.056. The general low variability between replicate samples indicates minimal field and laboratory variability and increases confidence in the results. Important to note however, is that TSS concentrations reported as 2.3 mg/L or less were flagged by the analytical laboratory as being at trace levels, and results should be interpreted with caution. Travel blanks were not analyzed for TSS. 200

373 mg/L

528 mg/L

TSS concentration (mg/L)

180 160 140 120

Mar 14 Apr 27 May 9 Aug 8 Sep 11 Sep 27/28

100 80 60 40 20 0 Woodward Avenue WWTP

Skyway WWTP

Red Hill Creek

Indian Creek Grindstone Creek

Desjardins Canal

Figure 8: Mean replicate TSS concentration measured at six stations during summer 2007 event-based sampling. Notes: Error bars represent plus and minus one standard deviation of replicate samples.

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2007 Field Season in Hamilton Harbour

Table 7: Replicate mean TSS concentrations (mg/L) for event-based sampling conducted at the WWTPs and tributaries during 2007. Station March 14 April 27 May 9 August 8 September September Median of Spring Large Baseflow Small rain 11 27/28 all events freshet rain event Large rain Extreme event event rain event Woodward 09 03 0001 4.6 No data 8.1 4.8 4.9 9.7 4.9 Avenue WWTP Skyway WWTP 09 03 0002 3.5 2.5 2.2 3.6 4.5 8 3.6 Red Hill Creek 09 15 0007 373 116 5.7 36.9 39.5 125 77.8 Indian Creek 09 15 0003 166 19.7 4.1 18.4 30.7 26 22.9 Grindstone 09 15 0009 528 18.7 2.1 4.8 29.9 6.2 12.5 Creek Desjardins 09 15 0008 72 56.6 18.2 22.5 18 42.5 32.5 Canal

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2007 Field Season in Hamilton Harbour

Relatively low TSS concentrations (<10 mg/L) were consistently measured during all events at both the Woodward Ave and Skyway WWTPs, during the May 9 baseflow event at the three tributaries (Red Hill Creek, Indian Creek, Grindstone Creek), and also during the August 8 and September 27 wet events at Grindstone Creek. Notably high TSS concentrations (>100 mg/L) were measured during the March 14 spring freshet event at the three tributaries (Red Hill Creek, Indian Creek, Grindstone Creek) and also during the April 27 and September 27 wet events at Red Hill Creek. Of the three tributaries, median TSS concentrations were highest at Red Hill Creek followed by Indian Creek and Grindstone Creek. Although Grindstone Creek had the lowest median TSS concentration of the tributaries, the overall maximum TSS concentration in the 2007 dataset was measured at Grindstone Creek during the March 14 spring freshet event (528 mg/L). In terms of TSS concentrations, Grindstone Creek may not respond as strongly to storm events as Indian Creek or especially Red Hill Creek (relatively more urbanized watersheds), but 2007 spring freshet TSS concentrations in this watershed appeared anomalously high for reasons not known. TSS concentrations measured at the Desjardins Canal among events were less variable relative to the temporal variability observed at the three tributaries; however, absolute TSS concentrations ranged between 18 mg/L and 72 mg/L (median 32.5 mg/L), concentrations on par with or greater than TSS concentrations observed in Indian Creek and Grindstone Creek during most of the events monitored. Interestingly, the temporal TSS pattern observed at the Desjardins Canal was quite similar to that observed at Red Hill Creek, with the highest TSS concentration measured during spring freshet, and noticeably high TSS concentrations also observed during the April 27 and September 27 wet events. There is no quantitative provincial water quality objective (PWQO) (MOEE, 1994) or Canadian water quality guideline (CWQG) (CCME, 2003) for TSS, although narrative criteria are available for turbidity. TSS was included in the 2007 Hamilton Harbour water sampling dataset primarily to assist in interpretation of PAH and PCB concentration results.

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2007 Field Season in Hamilton Harbour

3.2 Polycyclic Aromatic Hydrocarbons (PAHs) 3.2.1 Total PAH Concentrations Replicate mean ÎŁ15PAH concentrations for the event-based sampling conducted at the WWTPs and tributaries are summarized in Table 8. Variability within each set of replicate samples was generally low. The coefficient of variation (CV) was calculated for each replicate set of PAH concentrations (CV = standard deviation/mean), with a CV of zero signifying no difference between replicate samples. For the 2007 WWTP and tributary dataset, CVs ranged from 0 (multiple stations) to 0.18 (Indian Creek, September 27, 2007; replicates: 969 ng/L, 748 ng/L) and had an overall median CV of 0.00699. The low variability between replicate samples indicates minimal field and laboratory variability and increases confidence in the results. All travel blanks had all 15 PAH compounds analyzed below their respective detection limits (Table 8; Appendix IV), and as such, PAH concentration data were not blank corrected. Many of the 15 PAH compounds analyzed were below their respective detection limits for much of the 2007 sample dataset, particularly the higher molecular weight compounds. PAH concentration results in Table 8 represent an upper limit or maximum total PAH concentrations as results were tabulated assuming PAH compounds less than detection were equal to detection limits. As such, total ÎŁ15PAH concentrations reported at or near 181 ng/L in Table 8 suggest relatively low PAH presence. A less conservative approach to estimating total PAH concentration is presented in Figure 9, whereby total PAH concentrations presented exclude PAH compounds that were not quantified above their respective detection limit. This latter approach represents the minimum total PAH concentration for each sample.

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2007 Field Season in Hamilton Harbour

Table 8: Replicate mean total Σ15PAH concentrations (ng/L) for event-based sampling conducted at the WWTPs and tributaries during 2007. Station March 14 April 27 May 9 August 8 September 11 September 27/28 Median of Spring Large Baseflow Small Large rain Extreme rain all events freshet rain event rain event event event Woodward 09 03 0001 <288a No data <240 <215 <621 <226 <240 Avenue WWTP Skyway WWTP 09 03 0002 <181 <181 <181 <181 <181 <181 <181 Red Hill Creek 09 15 0007 <335 <624 <183 <254 <193 <459 <295 Indian Creek 09 15 0003 <321 <249 <182 <537 <240 <859 <285 Grindstone 09 15 0009 <790 <183 <181 <182 <181 <181 <182 Creek Desjardins 09 15 0008 <214 <226 <182 <183 <181 <189 <186 Canal Travel blanksa See Table <181 <181 <181 <181 <181 <181 <181 3 Notes: Concentrations represent an upper limit as any PAH compound reported by the lab as “less than detection” was assumed equal to its detection limit for purposes of calculating total PAH concentration. The sum of the detection limits for the 15 PAH compounds analyzed is 181 ng/L (Appendix IV). a – Only 1 replicate sample

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Detectable total PAH concentration (ng/L)

2007 Field Season in Hamilton Harbour Mar 14 Apr 27 May 9 Aug 8 Sep 11 Sep 27/28

1000 900 800 700 600 500 400 300 200 100 0 Woodward Avenue WWTP

Skyway WWTP

Red Hill Creek Indian Creek

Grindstone Creek

Desjardins Canal

Figure 9: Replicate mean total Σ15PAH concentrations (ng/L) measured at six locations during six events monitored in Hamilton Harbour during 2007. Notes: Error bars represent plus and minus one standard deviation of replicate samples. “Detectable” total PAH concentrations refers to minimum PAH concentrations which were calculated through excluding PAH compounds that were not quantified above their respective detection limit.

The event during which the highest total Σ15PAH concentration was observed differed between stations; no one event stood out in terms of having consistently high PAH concentrations, although none of the highest PAH concentrations were observed during baseflow. For all events sampled, the highest total PAH concentrations were observed: • At the Woodward Ave WWTP (<621 ng/L) on September 11, 2007 following a large rain event; • In Red Hill Creek (<624 ng/L) and the Desjardins Canal (<226 ng/L) on April 27, 2007 following a large rain event; • In Indian Creek (<859 ng/L) on September 27, 2007 following an extreme rain event; and • In Grindstone Creek (<790 ng/L) on March 14, 2007 during spring freshet. PAH concentrations at the Skyway WWTP were consistently below detection limits (<181 ng/L), so no analysis can be discerned for this sample set. The highest 2007 median total Σ15PAH concentration of all stations sampled was in Red Hill Creek (<295 ng/L); and the 2007 overall maximum total Σ15PAH concentration during any one event was measured in Indian Creek (<859 ng/L) on September 27, 2007. In general, Red Hill Creek and Indian Creek had similar total Σ15PAH concentrations, and both tributaries had consistently higher PAH concentrations than those measured in Grindstone Creek except for on the March 14, 2007 sampling event; only during spring freshet did Grindstone Creek have elevated Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

PAH concentrations. These spatial and temporal patterns observed at the three tributaries may be reflecting the relatively higher urbanization in the Red Hill Creek and Indian Creek watersheds, and the ephemeral observation of high PAH concentrations during periods of particularly high TSS load is likely due to the association of higher molecular weight PAHs with particles.

Detectable total PAH concentration (ng/L)

A very high concentration of TSS was observed at Grindstone Creek during spring freshet (Figure 8; Table 7), which likely explains the anomalously high total Σ15PAH concentration observed on the March 14 sampling event. Additional interpretation of the spring freshet sample from Grindstone Creek is discussed in Section 3.2.3 PAH Compound Profiles. In general however, correlations between TSS and total Σ15PAH concentrations were poor at the WWTPs, Red Hill Creek and Indian Creek (Figure 10). The R2 regression values at these sources ranged from 0.0015 (Indian Creek) to 0.17 (Woodward Ave WWTP); an R2 value could not be computed for Skyway WWTP. These poor regressions may in part be due to many PAH compounds being below their respective detection limits, but likely also reflect dissolved-phase transport of many PAHs. The R2 value for the Grindstone Creek regression was high (0.998), although as mentioned previously, this regression is driven by the high TSS and PAH concentrations during one particular event (spring freshet). The R2 value for the Desjardins Canal regression was also high (0.86), and may be reflecting the more ambient nature of this station relative to the WWTPs and tributaries.

800 700 600 500 Woodward Avenue WWTP

400

Skyway WWTP

300

Red Hill Creek

200

Indian Creek Grindstone Creek

100

Desjardins Canal

0 0

100

200

300

400

500

600

TSS concentration (mg/L)

Figure 10: Correlations between total Σ15PAH and TSS concentrations for eventbased sampling conducted at six stations during 2007.

Notes: Regression equations and lines are not shown for illustrative purposes; however, R2 values are described in the text. Detectable PAH concentrations for Skyway WWTP were 0 for all events.

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2007 Field Season in Hamilton Harbour

In addition, consistently higher total Σ15PAH concentrations were observed at Woodward Ave WWTP (median: <240 ng/L) relative to the Skyway WWTP (median: <181 ng/L), the latter of which had PAH concentrations less than detection for all sampled events. This pattern between the WWTPs may be reflecting the inputs of urban runoff as incorporated into Hamilton’s CSO system routed to the Woodward Ave WWTP, relative to the Skyway WWTP which does not serve a combined sewer system. The total Σ15PAH concentrations at the Woodward Ave WWTP were generally less variable than those in the tributaries. PAH concentrations at the Woodward Ave WWTP ranged by 2.9 fold, while PAH concentrations at Red Hill Creek, Indian Creek and Grindstone Creek ranged 3.4, 4.7 and 4.4 fold, respectively. Important to note however, is that total Σ15PAH concentrations in the tributaries were generally higher than the WWTPs and PAH concentrations at the Desjardins Canal were generally quite low relative to those observed at the tributaries (Table 8).

3.2.2 PAH Loadings Estimated total PAH loadings to Hamilton Harbour during 2007 are summarized in Table 9. Sample size and temporal variability were too low to use a loading calculation method such as the Beale Ratio estimator. In addition, flow data from all sources during the 2007 sampling season are not known. As such, 2007 PAH loading estimates are cursory in nature; however, low, base case and high loading scenarios were estimated to provide a range of potential PAH loadings from each source in the absence of using more rigorous methods. The loading method used however is consistent with the end use of the data, that being relative loading comparisons and demonstration of potential PAH loadings to the Harbour from external sources. The estimated 2007 total PAH loading to Hamilton Harbour from all sources examined ranged from 7,415 g/year to <209,417 g/year, with a base case or best estimate of <64,548 g/year. Estimated total PAH loadings were highest from the Woodward Ave WWTP (<28,092 g/year), followed by the Desjardins Canal (14,713 g/year). The other four sources examined (Skyway WWTP and 3 tributaries) each had estimated total PAH loadings of around 5,000 g/year. Estimated total PAH loading was generally reflective of flow volumes, although loadings from the Skyway WWTP were relatively low given that PAH concentrations from this source were consistently less than detection. The 2007 total PAH loads to Hamilton Harbour appear to be reasonable given order of magnitude comparisons with 1991-1992 Toronto PAH compound loads summarized in Boyd et. al. (1999). Although a direct comparison is not advisable due to differences in methods between the two studies, estimated 2007 PAH loads to Hamilton Harbour are likely lower than estimated 1991-1992 Toronto PAH loads. For example, the annual loads for fluoranthene alone from Etobicoke Creek and Mimico Creek were ~35 kg and 9.3 kg, respectively, values in line with total PAH loads listed for the base case scenarios shown in Table 9.

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Table 9: Estimated low, base case and high PAH loads to Hamilton Harbour from six input sources

Woodward Ave WWTP

Flow (millions m3/year) (HH RAP, PAH concentration (ng/L)b PAH Loading (g/year) 2004)a Min Median Max Min Median Max Low Base High Case 111.95 117.05 146 64 <240 <621 7,165 <28,092 <90,666

Skyway WWTP Red Hill Creek

29.76 13.88

31.72 20.14

43.07 31.05

0 7

<181 <295

<181 <624

0 97

<5,741 <5,941

<7,796 <19,375

Indian Creek

13.88

20.14

31.05

11

<285

<859

153

<5,740

<26,672

Grindstone Creek

11.93

23.74

38.91

0

<182

<790

0

<4,321

<30,739

Desjardins Canal

46.87

79.10

151.19

0

<186

<226

0

<14,713

<34,169

7,415

<64,548

<209,417

Source

Total

Notes: a) For Woodward Ave and Skyway WWTPs, “Min” and “Median” represent the lowest and median total annual flow volume at each plant for 1996-2002 as shown in HH RAP (2004), while “Max” represents the design flow of 400 megalitres/day (MLD) and 118 MLD, respectively. For Red Hill Creek and Grindstone Creek flow, “Min”, “Median” and “Max” represent the lowest, median, and maximum total annual flow volume for 19962002 as shown in HH RAP (2004). For Indian Creek, flow was assumed equal to Red Hill Creek as no flow information was available. For Desjardins Canal, “Min”, “Median” and “Max” represent the lowest, median and maximum total annual flow volume for 1996-2002 as shown in HH RAP (2004), assuming flow into Cootes Paradise equal the flow leaving through the Desjardins Canal. b) For PAH concentration, “Min” represents the lowest detectable mean total PAH concentration of the six events as shown in Figure 9; “Median” represents the median mean total Σ15PAH concentration of the six events as shown in Table 8; “Max” represents the maximum mean total Σ15PAH concentration of the six events as shown in Table 8.

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2007 Field Season in Hamilton Harbour

3.2.3 PAH Compound Profiles PAH compound profiles from the Woodward Ave WWTP and tributaries were examined to determine any differences in PAH profiles between the sources and/or between event types (Figure 11). PAH compound profiles from all Skyway WWTP and travel blank samples could not be examined as all PAH compounds analyzed in these samples were below detection limits. Additionally, PAH compound profiles from Grindstone Creek samples collected May 9, September 11 and September 27 and PAH compound profiles from Desjardins Canal samples collected September 11 also could not be examined as PAH compounds analyzed were all below detection limits. A qualitative examination of the PAH profiles demonstrated that generally, a similar PAH signature was observed between the different stations, and between the different events sampled. This typical PAH signature observed in the 2007 event-based sampling dataset is dominated by fluoranthene, followed by pyrene, and phenanthrene; other PAHs typically observed include chrysene and some of the lower molecular weight compounds, up to and including benzo(k)fluoranthene. Higher molecular weight PAH compounds from perylene through dibenzo(a,h)anthracene were generally not detected in the 2007 event-based dataset. One exception is the September 11 sample from Woodward Ave WWTP which had detectable levels of benzo(g,h,i)perylene; this observation is likely reflecting the overall higher total PAH concentration in this sample relative to the other events sampled. The other exception is the March 14 sample from Grindstone Creek, which had detectable levels of indeno(1,2,3-cd)pyrene and benzo(g,h,i)perylene. This anomalous observation is likely reflecting the very high TSS concentration observed during this event in Grindstone Creek (Figure 8; Table 7), as higher molecular weight PAHs are typically associated with particles, as is explained further below. The dominance of fluoranthene, pyrene and phenanthrene in the PAH profiles of WWTP and tributary waters likely reflects a combination of these compounds’ physicalchemical properties and environmental abundance. PAH compounds with lower molecular weight generally have relatively higher water solubilities than PAH compounds of higher molecular weight. In fact, of the 15 PAH compounds analyzed in this study, the three most water soluble compounds and their water solubilities at 25°C are phenanthrene (435 ug/L), fluoranthene (260 ug/L) and pyrene (133 ug/L); the compound with the next highest solubility is anthracene with a solubility of 59 ug/L at 25°C (BC MOE, 1993). Pending the physical-chemical property of each PAH compound, some compounds have an affinity to volatilize to the atmosphere (low molecular weight), some have an affinity to remain in the dissolved phase (mid-range molecular weight), and some have an affinity to partition to suspended or bottom sediment (high molecular weight). Such physical-chemical properties play a large role in the environmental fate of PAH compounds and what PAH compounds are detected in environmental whole water samples.

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Detectable PAH concentration (ng/L) 250

Detectable PAH concentration (ng/L) 250

Detectable PAH concentration (ng/L) 250

0

Hamilton Harbour Remedial Action Plan Indian Creek Mar 14 rep ave Indian Creek Apr 27 rep ave Indian Creek May 9 rep ave Indian Creek Aug 8 rep ave Indian Creek Sep 11 rep ave Indian Creek Sep 27 rep ave

100

50

0 PERYLENE

DIBENZO(AH)ANTHRACENE

BENZO(G,H,I) PERYLENE

INDENO(1,2,3-CD) PYRENE

200

7,12DIMETHYL(B)ANTH'ENE

250

DIBENZO(AH)ANTHRACENE

BENZO(G,H,I) PERYLENE

INDENO(1,2,3-CD) PYRENE

7,12DIMETHYL(B)ANTH'ENE

PERYLENE

BENZO (K) FLUORANTHENE

150

BENZO (B) FLUORANTHENE

200

BENZO (K) FLUORANTHENE

BENZO(E)PYRENE

BENZO(A)PYRENE

250

BENZO (B) FLUORANTHENE

BENZO(E)PYRENE

BENZO(A)PYRENE

CHRYSENE

BENZO(A)ANTHRACENE

FLUORANTHENE

PYRENE

ANTHRACENE

PHENANTHRENE

0

CHRYSENE

50

FLUORANTHENE

100

BENZO(A)ANTHRACENE

Woodward WWTP Sep 28 rep ave

Woodward WWTP Sep 11 rep ave

PYRENE

150

ANTHRACENE

Woodward WWTP May 9 rep ave

PHENANTHRENE

Woodward WWTP Mar 14 (1 rep)

Detectable PAH concentration (ng/L)

DIBENZO(AH)ANTHRACENE

BENZO(G,H,I) PERYLENE

INDENO(1,2,3-CD) PYRENE

7,12DIMETHYL(B)ANTH'ENE

PERYLENE

BENZO (K) FLUORANTHENE

Woodward WWTP Aug 8 rep ave

Detectable PAH concentration (ng/L)

DIBENZO(AH)ANTHRACENE

BENZO(G,H,I) PERYLENE

INDENO(1,2,3-CD) PYRENE

7,12DIMETHYL(B)ANTH'ENE

PERYLENE

BENZO (K) FLUORANTHENE

BENZO (B) FLUORANTHENE

BENZO(E)PYRENE

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CHRYSENE

BENZO(A)ANTHRACENE

FLUORANTHENE

PYRENE

ANTHRACENE

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DIBENZO(AH)ANTHRACENE

BENZO(G,H,I) PERYLENE

INDENO(1,2,3-CD) PYRENE

7,12DIMETHYL(B)ANTH'ENE

150

PERYLENE

200

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150

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BENZO(E)PYRENE

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CHRYSENE

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FLUORANTHENE

PYRENE

200

BENZO (B) FLUORANTHENE

BENZO(E)PYRENE

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FLUORANTHENE

PYRENE

ANTHRACENE

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0

ANTHRACENE

0

PHENANTHRENE

2007 Field Season in Hamilton Harbour Red Hill Creek Mar 14 rep ave Red Hill Creek Apr 27 rep ave Red Hill Creek May 9 rep ave Red Hill Creek Aug 8 rep ave Red Hill Creek Sep 11 rep ave Red Hill Creek Sep 27 rep ave

100 50

Grindstone Creek Mar 14 rep ave Grindstone Creek Apr 27 rep ave Grindstone Creek Aug 8 rep ave

150

100 50

Desjardins Canal Mar 14 rep ave Desjardins Canal Apr 27 rep ave Desjardins Canal May 9 rep ave Desjardins Canal Aug 8 rep ave Desjardins Canal Sep 27 rep ave

100

50

Figure 11: PAH profiles for event-based samples collected from Woodward Ave WWTP, Red Hill Creek, Indian Creek, Grindstone Creek and the Desjardins Canal during summer 2007.

Notes: “Detectable” total PAH concentrations refers to minimum PAH concentrations which were calculated through excluding PAH compounds that were not quantified above their respective detection limit.

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2007 Field Season in Hamilton Harbour

The PAH profiles presented in Figure 11 are also influenced by environmental abundance. The proportion of PAH compounds in PAH profiles differ depending on the contributing source with the largest PAH sources playing the largest potential role in impacting the signature. Of the PAH compounds analyzed in this study, the compounds found in highest abundance in urban air (in decreasing abundance) are: phenanthrene, fluoranthene and pyrene (Harner and Bidleman, 1998; Motelay-Massei et al., 2005). The PAH profile of urban runoff water is dominated by fluoranthene and phenanthrene, with smaller proportions of several other PAH compounds (Hoffman et al., 1984; Labencki, 2004). The process of atmospheric deposition and subsequent washoff of PAHs from urban surfaces during storm events alters the PAH profile and compound proportions found in urban runoff relative to that in urban air, even with no other PAH source (e.g. asphalt) contributing to runoff (Labencki, 2004). An example of this phenomenon is the approximately equal proportions of fluoranthene and phenanthrene in urban washoff (Labencki, 2004) as opposed to higher proportions of phenanthrene relative to fluoranthene in urban air. Overall, there is a complex interplay of factors which determine measured PAH compound profiles in water samples, the details of which are beyond the scope of the 2007 study. Nonetheless, the contribution of PAH sources such as vehicular emissions and coal tar to in-Harbour PAH concentrations has been addressed by Sofowote et al. (2008) in their source apportionment work for Hamilton Harbour. Exceptions to the general fluoranthene, pyrene and phenanthrene pattern in the 2007 sample dataset can also reveal where there may be an anomaly, i.e. a potential change in PAH source. An interesting observation is that for the events which had relatively high total PAH concentrations in Indian Creek (August 8, September 27), the PAH pattern was still dominated by fluoranthene, but phenanthrene was more abundant than pyrene. Too few samples were collected to know if this is a significant observation reflective of an anomaly that occurred in Indian Creek, or if it is merely reflective of environmental variability. Another interesting observation is the March 14 PAH profile pattern at Grindstone Creek. As mentioned previously, some higher molecular weight PAH compounds were detected, but also interesting is the almost even proportion of a broad range of PAH compounds in the sample, from the lighter, more water soluble PAH compounds through to the heavier, less water soluble PAH compounds. Again, this pattern is likely reflecting the very high TSS concentration measured during this event (Figure 8; Table 7), rather than the signature characterized by high proportions of more water soluble PAHs, such as observed typically in Red Hill Creek and Indian Creek, watersheds which have a higher degree of urbanization and impervious surfaces, and hence, high contributions of urban runoff. PAH concentrations in the waters of Grindstone Creek may typically be lower than Indian Creek and Red Hill Creek; however, the likely source of PAHs in Grindstone Creek - particle loads, rather than the presence of dissolved phase PAH as is detected in stormwater â&#x20AC;&#x201C; affects the PAH compound profile delivered to the Harbour. This difference in PAH source at Grindstone Creek and hence PAH profile may have fate, transport, source control and biological implications for the Harbour, the details of which are beyond the scope of this report.

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2007 Field Season in Hamilton Harbour

Further interpretation of PAH compound concentrations in the event-based 2007 sample set1 through comparison to relevant water quality guidelines such as the PWQOs (MOEE, 1994) or CWQGs (CCME, 2003) is challenging as the analytical method used (MOE PAH3435; Appendix IV) has detection limits for most of the PAH compounds close to or greater than the guidelines (Table 10). In fact, any quantifiable detection of the following PAH compounds under MOE method PAH3435 equates to exceedence of each compound’s respective PWQO: • Anthracene • Fluoranthene • Benzo(a)anthracene • Chrysene • Benzo(k)fluoranthene • Perylene • Benzo(g,h,i)perylene • Dibenzo(a,h)anthracene The only PAH compound that was analyzed with a PWQO greater than its detection limit is phenanthrene. Table 10: Provincial Water Quality Objectives (PWQOs), Canadian Water Quality Guidelines (CWQGs) and detection limits for 15 PAH compounds analyzed PAH Compound PWQO1 CWQG2 MOE (ng/L) (ng/L) method PAH3435 detection limit (ng/L) Phenanthrene 30 400 10 Anthracene 0.8 12 10 Pyrene n/a 25 10 Fluoranthene 0.8 40 10 Benzo(a)anthracene 0.4 18 20 Chrysene 0.1 n/a 10 Benzo(a)pyrene n/a 15 1 Benzo(e)pyrene n/a n/a 10 Benzo(b)fluoranthene n/a n/a 10 Benzo(k)fluoranthene 0.2 n/a 10 Perylene 0.07 n/a 10 7,12n/a n/a 10 Dimethyl(b)anth’ene Indeno(1,2,3-cd)pyrene n/a n/a 20 Benzo(g,h,i)perylene 0.02 n/a 20 Dibenzo(a,h)anthracene 2 n/a 20 Notes: 1 – PWQOs: MOEE (1994); 2 – CWQGs: CCME (2003)

1

Water quality guidelines such as the PWQOs and CWQGs are intended for ambient water quality and therefore not applicable to WWTP effluent. Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

Many PAH compounds also have CWQGs, and for compounds which have both a PWQO and CWQG, the PWQO is consistently a more stringent target. The CWQGs are greater than equivalent PWQOs by about an order of magnitude, and because of their higher absolute value, detection of PAH compounds with CWQGs doesn’t necessarily translate to exceedence of its CWQG. Of the six PAH compounds with CWQGs, only benzo(a)anthracene has a CWQG less than the detection limit under MOE method PAH3435, meaning any detection of benzo(a)anthracene equates to exceedence of its CWQG. Where quantifiable concentrations of PAH compounds were measured (i.e. greater than detection limits), PAH compound concentrations were compared to their respective PWQO and/or CWQG where guidelines exist. Generally, Red Hill Creek and Indian Creek demonstrated similarity in terms of their exceedence pattern of available PWQOs and CWQGs for PAH compounds analyzed in the 2007 dataset. For the water samples collected from these stations: • phenanthrene concentrations often exceeded the PWQO; however, the CWQG for phenanthrene was not exceeded for the events sampled in 2007; • anthracene concentrations exceeded the PWQO and CWQG for some events; • pyrene concentrations often exceeded the CWQG; • fluoranthene concentrations always exceeded the PWQO, and often exceeded the CWQG; • chrysene concentrations exceeded the PWQO for some events; • benzo(a)pyrene concentrations exceeded the CWQG for some events; and • benzo(k)fluoranthene concentrations exceeded the PWQO for one event. Concentrations of benzo(a)anthracene, perylene, benzo(g,h,i)perylene and dibenzo(a,h)anthracene were below detection limits meaning exceedence or meeting of the guidelines for these compounds cannot confidently be determined. Overall, the PWQOs and often the CWQGs are routinely exceeded for the lower molecular weight PAHs analyzed in this study for event-based samples collected from Red Hill Creek and Indian Creek. For samples collected from Grindstone Creek, many of the PAH compounds analyzed were below detection limits so exceedence of the available PWQOs and CWQGs cannot be determined with confidence. The April 27 event demonstrated fluoranthene concentrations in exceedence of the PWQO; however, most of the water quality guideline exceedences at Grindstone Creek were observed for the March 14 spring freshet sample. The PWQO was exceeded for: phenanthrene, anthracene, fluoranthene, benzo(a)anthracene, chrysene, benzo(k)fluoranthene, and benzo(g,h,i)perylene; and the CWQG was exceeded for: phenanthrene, pyrene, fluoranthene, benzo(a)anthracene, and benzo(a)pyrene. The Desjardins Canal sample set is similar to the Grindstone Creek sample set in that many of the PAH compounds analyzed were below detection limits so exceedence of the available PWQOs and CWQGs cannot be determined with confidence. For the water samples collected from the Desjardins Canal: • phenanthrene concentrations were routinely below the PWQO and CWQG; • pyrene concentrations were on par with the CWQG for two events; • fluoranthene concentrations routinely exceeded the PWQO, and were routinely Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

â&#x20AC;˘

below the CWQG chrysene concentrations exceeded the PWQO for one event.

Additional interpretation of PAH results can also be provided through comparing PAH compound concentrations measured during 2007 to those measured in other studies, both earlier studies in Hamilton Harbour and in another urban area. During 1988 â&#x20AC;&#x201C; 1991, 11 influent sources to Hamilton Harbour were centrifuged (six of which were included in the 2007 study) and the centrifuged particles were submitted for chemical analysis (Boyd, 2001). Although the study reported by Boyd (2001) is not directly comparable to the 2007 dataset reported herein due to the difference in media sampled (2007: whole water; 1988-1991: particle-phase only), the Boyd (2001) results can be used to demonstrate if the relative PAH contribution of sources in 1988-1991 are similar to the relative PAH contribution of sources measured during 2007. The three most abundant PAH compounds found in the event-based 2007 dataset (fluoranthene, pyrene, phenanthrene) were examined in terms of their relative presence among sources in the 1988-1991 dataset. Of the sources examined during 2007 (Table 1), the median fluoranthene, pyrene and phenanthrene particle-bound concentrations in the 1988-1991 dataset were highest from the Woodward Ave WWTP, followed by Indian Creek; the lowest median concentrations were measured from the Skyway WWTP. Thus, some changes may have occurred over time in terms of relative PAH concentrations in sources to Hamilton Harbour. PAH concentrations in Woodward Ave WWTP effluent appear to have decreased relative to the other sources as the highest PAH concentrations in 2007 were measured from Red Hill Creek and Indian Creek, followed by the Woodward Ave WWTP (Table 8). Another interesting observation is that in the 2007 dataset, PAH concentrations from Red Hill Creek and Indian Creek were on par with one another whereas in the 19881991 dataset, Indian Creek had consistently higher PAH concentrations relative to Red Hill Creek. Finally, for the sources examined, relative PAH concentrations from the Skyway WWTP were lowest in both the 1988-1991 and 2007 datasets, suggesting relatively low PAH concentrations from this source through time. The 1988-1991 dataset reported by Boyd (2001) was also examined in terms of the relative abundance of fluoranthene, pyrene and phenanthrene from the six sources of interest. From Woodward WWTP, Skyway WWTP and Grindstone Creek, the (decreasing) relative PAH abundance was pyrene, fluoranthene then phenanthrene; however, from Indian Creek, Red Hill Creek and the Desjardins Canal, the (decreasing) relative PAH abundance was fluoranthene, pyrene then phenanthrene. In the 2007 dataset, Indian Creek appeared to have an anomalous PAH profile relative to the other sources examined (Figure 11); however, Indian Creek did not appear anomalous in the 1988-1991 dataset following the cursory analysis applied. Direct comparison between the 2007 and 1991-1992 datasets is not advisable however, due to the differences in media sampled (whole water versus suspended sediment). The three most abundant PAH compounds found in the event-based 2007 dataset (fluoranthene, pyrene, phenanthrene) were also compared to concentrations measured during a 1991-1992 sampling campaign in six Toronto tributaries (Boyd et al., Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

1999). Generally, mean PAH concentrations observed in Red Hill Creek, Indian Creek and Grindstone Creek during 2007 were less than mean concentrations observed in Toronto tributaries monitored during 1991-1992 except for Highland Creek, which had PAH concentrations similar to Red Hill Creek and Indian Creek (Table 11). Thus, eventbased PAH concentrations in Red Hill Creek, Indian Creek and Grindstone Creek appear to be consistent with other urbanized watersheds. Table 11 also demonstrates that despite only having one dry sample for the 2007 dataset in Hamilton Harbour (i.e. baseflow - May 9, 2007), the finding of wet concentrations greater than dry concentrations during 2007 is consistent with the results of the 1991-1992 monitoring in the six Toronto tributaries.

2007 eventbased dataset

Toronto area rivers 19911992 (Boyd et al., 1999)

Table 11: Mean fluoranthene, pyrene and phenanthrene concentrations (ng/L) in Red Hill Creek, Indian Creek and Grindstone Creek relative to concentrations measured during 1991-1992 in six Toronto rivers (Boyd et al., 1999). fluoranthene pyrene phenanthrene Etobicoke Creek Dry 20.7 22.4 5.8 Wet 627.1 906.1 16.4 Mimico Creek Dry 82.4 64.9 51.1 Wet 832.4 593.4 508.5 Humber River Dry 23.5 23.6 8.9 Wet 266.4 229.1 181.2 Don River Dry 30.8 27.9 21.7 Wet 174.7 157.4 139.2 Highland Creek Dry 5.6 7.1 1.4 Wet 66.6 61.1 95.5 Rouge River Dry 8.5 10.1 2.8 Wet 154.3 85.4 107.4 Red Hill Creek Indian Creek Grindstone Creek

Dry Wet Dry Wet Dry Wet

6.5 79.7 11 106.6 <detection 29.4

<detection 60.5 <detection 69.8 <detection 22.9

<detection 50.7 <detection 82.5 <detection 13.2

Notes: For the 2007 event-based dataset in Hamilton Harbour, “dry” conditions represent n=1 (May 9, 2007), and “wet” conditions represent (n=5). Mean concentrations for wet conditions were calculated assuming <detection = 0.

The relative abundance of fluoranthene, pyrene and phenanthrene in Red Hill Creek and Grindstone Creek is the same as that observed in Mimico Creek, Humber River and the Don River in Toronto (Table 11), and for Indian Creek, the pattern is the same as that for the Rouge River (Table 11). While the significance of this observation is not known, it is another line-of-evidence on the ubiquitous nature of these PAH compounds in urban watersheds.

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2007 Field Season in Hamilton Harbour

3.3 Polychlorinated biphenyls (PCBs) 3.3.1 Total PCB Concentrations Replicate mean PCB concentrations for the event-based sampling conducted at the WWTPs and tributaries are summarized in Table 12 following two methods of estimating total PCB concentrations; results are presented graphically in Figure 12 following one method of estimating total PCB concentrations. Variability within each set of replicate samples was generally low, although a few samples did demonstrate substantial variability in PCB concentrations between replicates. Variability between the replicate samples for PCB concentrations was relatively higher than for replicate TSS and PAH concentrations; it is unknown if the PCB replicate samples were more variable due to higher environmental variability, or due to the analytical-based variability. The CV was calculated for each replicate set of PCB concentrations. For the 2007 WWTP and tributary dataset, CVs ranged from 0.00298 (Woodward Ave WWTP, August 8, 2007; replicates: <10.5043 ng/L, <10.5487 ng/L) to 0.469 (Red Hill Creek, August 8, 2007; replicates: <1.1859 ng/L, <2.3628 ng/L) and had an overall median CV of 0.0832. Travel blanks generally had low PCB concentrations with a minimum concentration of 0.0066 ng/L on May 9, 2007 and a maximum, upper limit concentration of <0.91 ng/L on September 28, 2007 (Table 12). Most PCB congeners in the six travel blank samples were below their respective detection limits (Appendix IV); as such, PCB concentration data were not blank corrected. Nonetheless, a caveat to this is that PCB concentrations from a few stations during a few events were close to the travel blank PCB concentration quantified during that event, e.g. Grindstone Creek on September 27, 2007: 0.15 ng/L; travel blank: 0.13 ng/L. Such situations are indicative of the relatively low PCB sample concentrations measured during these events as PCB concentrations were quantified down to absolute levels considered very low by analytical standards. Nonetheless, even with a positive correlation between total PCB concentration in the travel blanks and the total PCB concentration in the sample at the station where the travel blank was collected (Figure 13), potential sample contamination remains relatively low as travel blanks ranged from 0.32% to 3.4% (median 0.51%) of corresponding station sample PCB concentrations.

2

CVs were based on total PCBs estimated through assuming that PCB congeners less than detection were equal to the detection limit (i.e. maximum or upper limit total PCB concentrations).

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2007 Field Season in Hamilton Harbour

Table 12: Replicate mean total Σ82PCB concentrations (ng/L) for event-based sampling conducted at the WWTPs and tributaries during 2007. March 14 April 27 May 9 August 8 September 11 September Median of all Spring freshet Large rain Baseflow Small rain Large rain 27/28 events Station event event event Extreme rain event Min1 Max2 Min1 Max2 Min1 Max2 Min1 Max2 Min1 Max2 Min1 Max2 Min1 Max2 Woodward 1.05 <1.48 No No 2.08 <2.28 10.29 <10.53 4.69 <4.82 24.14 <24.19 4.69 <4.82 Avenue WWTP data data Skyway WWTP 0.38 <1.11 0.48 <0.94 0.54 <1.12 0.59 <0.95 0.94 <1.39 0.20 <1.18 0.51 <1.12 Red Hill Creek 6.62 <7.01 2.45 <2.87 0.33 <0.75 1.01 <1.77 1.30 <1.73 3.94 <4.62 1.87 <2.32 Indian Creek 1.13 <1.51 0.35 <0.67 0.14 <0.67 0.19 <1.30 1.19 <1.60 0.71 <1.47 0.53 <1.39 Grindstone 3.40 <3.69 0.18 <0.61 0.041 <0.82 0.12 <1.11 0.59 <1.04 0.15 <0.69 0.16 <0.93 Creek Desjardins 1.76 <2.25 4.37 <4.79 1.88 <2.59 3.72 <4.49 3.61 <3.86 4.76 <5.13 3.67 <4.18 Canal Travel blanks3 0.026 <0.73 0.016 <0.59 0.0066 <0.67 0.052 <0.65 0.015 <0.71 0.13 <0.91 0.021 <0.69 See Table 3 Notes: 1 - “Min” or minimum total PCB concentrations were calculated assuming any PCB congener reported by the lab as “actual result is less than the reported value” (i.e. less than detection) was equal to zero for purposes of calculating minimum total PCB concentration; this is a less conservative approach to estimating total PCB concentration from reported PCB congener concentrations. 2 - “Max” or maximum total PCB concentrations represent an upper limit as any PCB congener reported by the lab as “actual result is less than the reported value” (i.e. less than detection) was assumed equal to its detection limit for purposes of calculating maximum total PCB concentration. 3 – Only 1 replicate sample

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Detectable total PCB concentration (ng/L)

2007 Field Season in Hamilton Harbour

25

Mar 14 Apr 27 May 9 Aug 8 Sep 11 Sep 27/28

20

15

10

5

0 Woodward Avenue WWTP

Skyway WWTP

Red Hill Creek

Indian Creek Grindstone Creek

Desjardins Canal

Travel blanks

Figure 12: Replicate mean total PCB concentrations (ng/L) measured at six locations during six events monitored in Hamilton Harbour during 2007. Notes: Error bars represent plus and minus one standard deviation of replicate samples. “Detectable” total PCB concentrations refers to minimum PCB concentrations which were calculated assuming any PCB congener reported by the lab as “actual result is less than the reported value” (i.e. less than detection) was equal to zero.

Total PCB concentration in travel blank (ng/L)

0.16 Travel blank collected at Woodward Ave WWTP

0.14

Travel blank collected at Skyway WWTP

0.12 0.1 0.08 0.06 0.04 0.02 0 0

5

10

15

20

25

30

Total PCB concentration in sample (ng/L)

Figure 13: Correlation between total PCB concentrations in travel blanks and total PCB concentrations in samples where travel blanks were collected.

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2007 Field Season in Hamilton Harbour

The event during which the highest total PCB concentration was observed differed between stations; no one event stood out in terms of having consistently high PCB concentrations, although none of the highest PCB concentrations were observed on April 27 (large rain event), May 9 (baseflow) or August 8 (small rain event). For all events sampled, the highest total PCB concentrations were observed: â&#x20AC;˘ At the Woodward Ave WWTP (<24.19 ng/L) and in the Desjardins Canal (<5.13 ng/L) on September 27/28, 2007 following an extreme rain event; â&#x20AC;˘ At the Skyway WWTP (<1.39 ng/L) and in Indian Creek (<1.60 ng/L) on September 11, 2007 following a large rain event; â&#x20AC;˘ In Red Hill Creek (<7.01 ng/L) and Grindstone Creek (<3.69 ng/L) on March 14, 2007 during spring freshet. Despite no overall pattern in temporal variability for all six stations, when stations are examined on an individual or grouped basis, patterns in temporal variability emerge and contribute to the overall high spatial variability in total PCB concentrations. The highest 2007 median total PCB concentration of all stations sampled was at the Woodward Ave WWTP (<4.82 ng/L); and the 2007 overall highest total PCB concentration during any one event was also measured at the Woodward Ave WWTP (<24.19 ng/L) on September 28, 2007, following an extreme rain event (Table 2; Appendix I). In addition to the station with the highest PCB concentrations, total PCB concentrations measured at the Woodward Ave WWTP were also highly variable and ranged over an order-of-magnitude for the events sampled (Figure 12; Table 12). Observation of the highest PCB concentrations at the Woodward Ave WWTP following the largest rain event as well as the highest overall PCB concentration of all WWTP and tributary stations sampled in this study suggests the potential for eventbased PCB contributions to the plant, that is, contributions from the combined sewer system. Relatively low total PCB concentrations at the Woodward Ave WWTP on March 14 and May 9 also support this supposition as runoff water to the combined system would have been minimal during spring freshet and baseflow events, respectively. The difference in temporal concentration patterns between PAHs (Figure 9) and PCBs (Figure 12) at the Woodward Ave WWTP confounds the results as a similar pattern might be expected if both PAH and PCB sources to the plant were similar, such urban runoff. Fate and transport processes of PAHs and PCBs in the urban environment differ which might also explain differences in temporal patterns, so further comparison between these chemical groups was not conducted. The total PCB concentrations at the Woodward Ave WWTP were not strongly correlated to paired TSS concentrations (Figure 14; R2 = 0.41) suggesting the high temporal variability at this station was not driven by fluctuations in particle concentrations, as PCBs have a strong affinity to bind to particles due their physicalchemical properties. Thus, temporal variability in PCB concentrations at the Woodward Ave WWTP appear to reflect pulses in PCB contributions to the plant, either through greater PCB concentrations on particles and/or higher dissolved phase PCB contributions.

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2007 Field Season in Hamilton Harbour

Woodward Avenue WWTP Skyway WWTP Red Hill Creek Indian Creek Grindstone Creek Desjardins Canal

Total PCB concentration (ng/L)

30 25 20 15 10 5 0 0

100

200

300 TSS (mg/L)

400

500

600

Figure 14: Correlation between total PCB and TSS concentrations at six stations for six events sampled in Hamilton Harbour during 2007.

Notes: Regression equations and lines are not shown for illustrative purposes; however, R2 values for each station regression are described in the text.

Total PCB concentrations from the Skyway WWTP (Figure 12; Table 12) demonstrated very little temporal variability - PCB concentrations only ranged 1.5 fold among the six events in contrast to the Woodard Ave WWTP where PCB concentrations ranged over an order-of-magnitude. The relative difference in temporal variability between the WWTPs may be rooted in the Skyway WWTP serving a separate sewer system with little influence from runoff waters which are delivered to the Woodward Ave WWTP from the combined sewer system during events. The WWTPs also differ as total PCB concentrations from the Woodward Ave WWTP were consistently higher than those measured at the Skyway WWTP (Table 12), and during the September 28, 2007 event, over two orders-of-magnitude higher. The two WWTPs are similar in one respect however, as the total PCB concentrations at the Skyway WWTP were also not correlated to paired TSS concentrations (Figure 14; R2 = 0.17) which is not surprising given that both TSS (Figure 8; Table 7) and PCB (Figure 12; Table 12) concentrations demonstrated little variability between events. The three tributaries examined in this study â&#x20AC;&#x201C; Red Hill Creek, Indian Creek, and Grindstone Creek (Figure 12; Table 12) â&#x20AC;&#x201C; all demonstrated some temporal variability during the 2007 season. Indian Creek had the lowest temporal variability of the tributaries as PCB concentrations demonstrated a range of 2.4 fold, and Red Hill Creek had the highest temporal variability at 9.3 fold, or approximately one order-ofmagnitude. Generally, temporal variability in the tributaries was less than that observed at the Woodward Ave WWTP, but greater than that at the Skyway WWTP. Red Hill Creek had the highest median total PCB concentration of the tributaries (<2.32 ng/L), followed by Indian Creek which had the next highest median total PCB concentration (<1.39 ng/L), and finally, Grindstone Creek which had the lowest median total PCB Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

concentration (<0.93 ng/L). Unlike the WWTPs, a potential partial explanatory factor for the temporal variability of PCB concentrations in two of the tributaries was paired TSS concentrations (Figure 14). Total PCB concentrations in Red Hill Creek and Grindstone Creek were strongly correlated to concomitant TSS concentrations (Figure 14), with R2 values of 0.91 and 0.97, respectively. However, these strong correlations are largely influenced by the March 14 spring freshet sampling event, the event when the highest total PCB concentrations were observed at each of these stations, alongside very high TSS concentrations (Table 7; Figure 8). Interestingly, during the March 14 spring freshet event, Grindstone Creek had a higher TSS concentration than Red Hill Creek, but Red Hill Creek had a higher PCB concentration than Grindstone Creek. This observation along with consistently higher PCB concentrations in Red Hill Creek relative to Grindstone Creek and Indian Creek suggests that the Red Hill Creek watershed is a greater PCB source area relative to Grindstone Creek and Indian Creek watersheds. This is in-line with expectations given the historical use of PCBs in the east end of Hamilton. TSS and temporal trends in Indian Creek were different relative to the other two tributaries examined. Total PCB concentrations in Indian Creek were not correlated to paired TSS concentrations (Figure 14; R2 = 0.21), unlike Red Hill Creek and Grindstone Creek. Also, the highest total PCB concentration was observed on the September 11 sampling event (<1.60 ng/L), not on the March 14 spring freshet event like Red Hill Creek and Grindstone Creek, although total PCB concentrations observed in Indian Creek on the March 14 spring freshet event (<1.51 ng/L) were similar in magnitude to September 11. While PCB concentrations in Indian Creek didnâ&#x20AC;&#x2122;t demonstrate a strong spring freshet spike in total PCB concentration like that observed in Red Hill Creek and Grindstone Creek, spring freshet conveyance of PCBs was also of note in Indian Creek. Total PCB concentrations at the Desjardins Canal demonstrated relatively low temporal variability, although not as low as that observed at the Skyway WWTP. Total PCB concentrations at the Canal demonstrated a 2.3 fold range in concentrations, similar in magnitude to the range observed in Indian Creek (2.4 fold). Overall, the total PCB concentrations at the Desjardins Canal were not correlated to paired TSS concentrations (Figure 14; R2 = 0.015), thus fluctuations in TSS concentrations do not appear to be an explanatory factor in temporal PCB trends observed at the Canal. Confounding the results however, they occasionally appear to play a role on an event basis and be an explanatory factor in variability between replicate samples. For example, the replicate samples collected on April 27 had PCB concentrations of 5.7 ng/L and 3.8 ng/L, and corresponding TSS concentrations of 66.3 mg/L and 46.9 mg/L, respectively, demonstrating a positive correlation between PCB and TSS concentrations. However, replicate samples collected on September 27 had PCB concentrations of 4.6 ng/L and 5.7 ng/L, and corresponding TSS concentrations of 41.1 mg/L and 43.8 mg/L, demonstrating the complex nature of TSS variability on PCB concentrations at the Desjardins Canal. A significant observation of the Desjardins Canal 2007 dataset is that the median total PCB concentration at the Canal is greater than the medians for the Skyway WWTP Hamilton Harbour Remedial Action Plan

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and the three tributaries monitored. This finding was not in-line with expectations as receiving water bodies such as Cootes Paradise are generally expected to have lower ambient contaminant concentrations relative to potential incoming sources. The temporal variability in total PCB concentrations at the Desjardins Canal and the lack of overall correlation between PCBs and TSS suggest complex PCB dynamics at the Canal. Source areas and/or the magnitude of contributions to PCB concentrations measured at the Desjardins Canal may shift pending the nature of the event and erratic hydrodynamics at the Canal. Direction of water flow at the Canal can be from Cootes Paradise to the Harbour, or visa versa, the latter of particular note due to seiche events. The six events monitored in 2007 as categorized in Table 2 may not correspond to conditions of water flow at the Desjardins Canal. Water sampled at the Desjardins Canal could be representative of conditions in Cootes Paradise or Hamilton Harbour, with predications of which scenario might prevail on what day not possible based on meteorological conditions alone. These complications were known in advance of sampling, but sampling was still conducted at the Canal as estimated Cootes Paradise PCB loadings would be conservative in nature and correspond to a “worst-case” scenario (1.4 2007 Field Season Limitations). In order to further interpret PCB results from the Desjardins Canal station, the field notes were referenced for qualitative observation of flow during each event monitored. For example, on March 14, 2007, “heavy flow from Cootes Paradise” was noted, but on September 27, 2007, “flow from Bay” was noted (D. Supper, 2007, pers. comm.). Upon examining water sampling results for these two events, a correlation between PCB concentration and direction of flow appears evident as March 14, 2007 had the lowest PCB concentration at the Desjardins Canal of <2.25 ng/L, while September 27, 2007 had the highest concentration of <5.13 ng/L. Further examination of the field notes suggests the relationship is not this simple. Field notes for April 27, 2007 indicate “flow in easterly direction” and the PCB concentration was <4.79 ng/L; for May 9, 2007, the notes indicate “significant lake effect flow” and “lake effect flow = east winds” and the PCB concentration was <2.59 ng/L; and for September 11, 2007, the notes indicate “flow from Cootes Paradise” and the PCB concentration was <3.86 ng/L (D. Supper, 2007, pers. comm.). Thus, noted flow from the Harbour doesn’t always coincide with relatively higher PCB concentrations. A possible reason may be strong currents at depth which are not visually apparent at the water surface. In summary, explanatory factors for the variability in PCB concentrations at the Desjardins Canal could not be discerned. For this reason and also because of elevated PCB concentrations at the canal, follow-up work is recommended to investigate if relatively high PCB concentrations at the Desjardins Canal are representative of conditions in Hamilton Harbour, or if they represent an uncharacterized source of PCBs to Cootes Paradise. Further interpretation of the 2007 event-based sample set was made through comparison of total PCB concentrations to the PWQO of 1 ng/L (MOEE, 1994)3; there is 3

Water quality guidelines such as the PWQOs and CWQGs are intended for ambient water quality and therefore not applicable to WWTP effluent. Hamilton Harbour Remedial Action Plan

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no current CWQG for PCBs as “[e]nvironmental exposure is predominantly via sediment, soil, and/or tissue, therefore, the reader is referred to the respective guidelines for these media (CCME, 2003, p.7). Median total PCB concentrations during 2007 (Table 12) were greater than the PWQO in Red Hill Creek and the Desjardins Canal, and less than the PWQO in Grindstone Creek; median total PCB concentrations in Indian Creek were approximately equal to the PWQO. Further examination of the data indicate that in Red Hill Creek, all events were greater than the PWQO except for baseflow. In Indian Creek, all events were approximately equal to the PWQO, except for the baseflow event which had total PCB concentrations less than the PWQO. The PWQO exceedence pattern in Grindstone Creek was again different, as only the spring freshet event had PCB concentrations greater than the PWQO; the other events and baseflow had PCB concentrations less than (or close to) the PWQO. In contrast to the tributaries, PCB concentrations at the Desjardins Canal were consistently above the PWQO for all events monitored in 2007. Additional interpretation of PCB results can also be provided through comparing PCB concentrations measured during 2007 to those measured in other studies, both earlier studies in Hamilton Harbour and another urban area. PCB concentrations from the Woodward Ave WWTP were monitored as far back as 1974 when a PCB concentration of 300 ng/L was measured in Woodward Ave WWTP effluent, and “[a]t that time, Hamilton had one of the highest PCB effluent concentrations in Ontario… (Shannon et al, 1976).” (MOE, 1986). Follow-up studies conducted in 1982-1983 found that the Woodward Ave and Skyway WWTPs had final effluent mean PCB concentrations of 43 (+/- 8) ng/L and 30 (+/- 13) ng/L, respectively; maximum PCB concentrations from these WWTPs were 190 ng/L and 200 ng/L, respectively (MOE, 1986). Comparison of relative PCB concentrations at the Woodward Ave and Skyway WWTPs for past and present time periods suggests that PCB concentrations in Skyway WWTP effluent used to be on par with concentrations measured in Woodward Ave WWTP effluent, whereas PCB concentrations in Woodward Ave WWTP effluent are now about an order-of-magnitude greater than concentrations in Skyway WWTP effluent. Assuming the historical monitoring data are representative of overall effluent conditions at both plants and respective sewersheds have remained static over time, PCB inputs to the Skyway WWTP likely declined at a much faster rate than PCB inputs to Woodward Ave WWTP following the 1970s decline in PCB use. A detailed study of seasonal variations of contaminant concentrations in Woodward Ave WWTP influent and effluent was made in 1982-1983 and reported in MOE (1987). This report found an overall average PCB concentration in effluent of 30 ng/L and that "influent levels of PCBs were highest during the summer season due mainly to a relatively heavy loading of 0.1 kg which occurred on August 8" (MOE, 1987, p.62). While event-based contributions may have had significant influence on PCB concentrations in influent (and subsequently effluent), MOE (1987) also suggested that “[a] further cause of excessive influent contaminant concentrations is the presence of industrial sources within the area. During cleanup operations or peak production periods, a particular industry or group of industries may account for shock loads of pollutants in the [WWTP] influent” (MOE, 1987, p.62). Although it is difficult to assess due to sparse historical monitoring data, the relative roles of event-based versus direct Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

industrial PCB contributions to WWTP influent loading have likely changed over time following the decline of active PCB use. The MOE (1987) study also demonstrated that PCB concentrations can vary widely between monitoring events and seasons. The winter average PCB effluent concentration was 60 ng/L, the spring average was 8.7 ng/L and summer average was 20 ng/L; this trend is in contrast to a winter average PCB influent concentration of 140 ng/L, a spring average of 70 ng/L and a summer average of 170 ng/L (MOE, 1987, p. B42). Thus, treatment processes at the plant play a role in the PCB concentrations in final effluent (removal efficiency of PCBs averaged 90%), and although solid versus liquid fractions were not analyzed separately in the 2007 dataset (whole water only), data in MOE (1987) show that PCB concentrations in influent and effluent were driven by PCB concentrations on the solid fraction (MOE, 1987, p. B-28). A point of note is that this is in contrast to trends undertaken by MOE (1987) for loads, whereby influent loads were driven by solid phase load, while effluent loads were driven by liquid phase load (MOE, 1987, p.B-42). A detailed discussion of loads is discussed in Section 3.3.2 PCB Loadings. PCB concentrations at the Woodward Ave WWTP were variable in the 2007 dataset, consistent with previous (MOE, 1987) monitoring efforts at the plant. Overall temporal trends suggest PCB concentrations to and from Woodward Ave WWTP appear to have declined over time as suggested in MOE (1986, p.11) and by comparison of historical monitoring data (MOE, 1986; MOE, 1987) to the 2007 dataset (Table 12) which had relatively lower PCB concentrations in effluent. This trend is likely due to decreased PCB usage and suggests that Woodward Ave WWTP may have historically been a much larger source of PCBs to the Harbour relative to current contributions from the plant4. Another dataset that provides historical context for the 2007 dataset is that reported in Boyd (2001). During 1988 â&#x20AC;&#x201C; 1991, 11 influent sources to Hamilton Harbour were centrifuged (six of which were included in the 2007 study) and the centrifuged particles were submitted for chemical analysis (Boyd, 2001). Although the study reported by Boyd (2001) is not directly comparable to the 2007 dataset reported herein due to the difference in media sampled (2007: whole water; 1988-1991: particle-phase only), the Boyd (2001) results can be used to demonstrate if the relative PCB contributions of sources are similar between the 1988-1991 and 2007 time periods. Of the sources examined during 2007 (Table 1), the median PCB particle-bound concentrations in the 1988-1991 dataset were highest from the Woodward Ave WWTP (305 ng/g dw); all other median PCB concentrations were less than the detection limit of 20 ng/g dw. Further interpretation of the 1998-1991 dataset is available through examining the maximum concentrations; maximum PCB concentrations were highest from the Woodward Ave WWTP (6300 ng/g dw), followed by the Skyway WWTP (180 ng/g dw), Red Hill Creek (80 ng/g dw), Desjardins Canal (55 ng/g) and Grindstone Creek/Indian Creek (<20 ng/g). A monitoring study by the MOE in the 1980s also found that PCB concentrations in tributaries were below detection limits (Harlow and Hodson, 4

Strathearne Ave CSO was also a relatively large historical source of PCBs to the Harbour according to MOE (1985) and Harlow and Hodson (1988).

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2007 Field Season in Hamilton Harbour

1988, p.35). Comparison of the 1988-1991 historical monitoring results (Boyd, 2001) to the 2007 dataset (Table 12; Figure 12) demonstrate that Woodward Ave WWTP has consistently had the highest PCB concentrations of the sources examined, and that the relative PCB concentrations from the sources examined have changed little over time. Red Hill Creek has consistently had higher PCB concentrations than those from Grindstone Creek and Indian Creek. One exception is that at present, the Skyway WWTP appears to have lower PCB concentrations relative to the other sources in contrast to the past when it appeared to be a relatively larger source to the Harbour; this finding is consistent with the other historical monitoring studies discussed above (MOE, 1986). Another source of data that aided in interpretation of 2007 Red Hill Creek monitoring results (Table 12; Figure 12) was the City of Hamilton Public Works Department (2008) report that summarized monitoring conducted in 2007 at the former Rennie and Brampton Street landfills. The Rennie and Brampton Street landfills were previously identified as contaminating the adjacent Red Hill Creek through leachate seeps, and as such, in 2003 (Rennie) and 2004 (Brampton), a leachate collection system came online in the area surrounding the closed landfill sites to mitigate contaminated groundwater from entering Red Hill Creek. Preliminary monitoring results from Red Hill Creek and leachate collection system suggested that the system appeared to be functioning as intended through mitigating the migration of impacted groundwater to the Creek (City of Hamilton Public Works Department, 2008). The 2007 monitoring reported herein includes a station in Red Hill Creek (09 15 0007), which is located downstream from the former Rennie Street landfill, but upstream from the Brampton Street landfill, meaning monitoring results at station 09 15 0007 in Red Hill Creek are likely integrative of any inputs from the Rennie Street landfill, but not the Brampton Street landfill. When examining PCB concentrations, this geography is significant as PCB concentrations in groundwater have generally been higher in the Rennie Street landfill relative to the Brampton Street landfill (City of Hamilton Public Works Department, 2008), so monitoring results from Red Hill Creek in 2007 are more likely to be conservative in nature. The groundwater monitoring conducted in 2007 as reported in City of Hamilton Public Works Department (2008) shows PCB concentrations up to 40,000 ng/L at MW644 (Rennie Street Landfill) on October 17, 2007, and concentrations over 1,000 ng/g at many stations during several monitoring occasions. Accompanying surface water samples collected from Red Hill Creek (stations SW1 through SW5) show PCB concentrations less than the detection limit of 50 ng/L (City of Hamilton Public Works Department, 2008). Although a detection limit of 50 ng/L is too high for a more rigorous analysis, the 2007 monitoring results reported herein for Red Hill Creek (Table 12) are consistent with the City of Hamilton Public Works Department results in that PCB concentrations in Red Hill Creek are orders of magnitude below PCB concentrations in Rennie Street landfill leachate, suggesting that PCB inputs from the Rennie Street landfill to Red Hill Creek are minimal if at all present. Although PCB concentrations were higher during 2007 in Red Hill Creek relative to Indian Creek and Grindstone Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

Creek (Table 12), this is likely due to the more urbanized nature of Red Hill Creek and historically higher use of PCBs in this watershed, rather than large direct inputs of PCBs from landfill leachate. A caveat to comparing the 2007 dataset reported herein to historical datasets is that field and lab methods were different between studies, and analytical capabilities have improved drastically over the past few decades. Nonetheless, comparison of the 2007 event-based dataset with earlier studies in Hamilton suggests that PCB concentrations from the WWTPs to Hamilton Harbour have declined over time, likely also leading to reduced PCB loadings to the Harbour due to the dominance of Woodward Ave WWTP in terms of PCB concentration (Figure 12) and flow. Regarding the tributaries, results suggest that PCB concentrations have always been highest in Red Hill Creek relative to Indian Creek and Grindstone Creek, and in all likelihood, PCB concentrations in Red Hill Creek have also declined over time due to the installation of leachate collection systems at the former Rennie and Brampton Street landfills. A regional interpretation on the 2007 Hamilton Harbour PCB concentration tributary results can be made through comparison to PCB concentrations measured during a 1991-1992 sampling campaign in Toronto tributaries (Boyd et al., 1999). Generally, mean PCB concentrations observed in Red Hill Creek, Indian Creek and Grindstone Creek during 2007 were less than mean concentrations observed in Toronto tributaries monitored during 1991-1992, by about an order-of-magnitude (Table 13). Thus, event-based PCB concentrations in Red Hill Creek, Indian Creek and Grindstone Creek do not appear anomalous when compared to another urban area, although a caveat to this is that PCB concentrations in Toronto streams have likely decreased since 1992. Also, despite only having one dry sample for the 2007 dataset in Hamilton Harbour (i.e. May 9, 2007), the finding of wet concentrations greater than dry concentrations during 2007 in Hamilton is consistent with the results of the 1991-1992 Toronto tributary monitoring (Table 13).

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2007 eventbased dataset

Toronto area rivers 1991-92 (Boyd et al., 1999)

Table 13: Mean PCB concentrations in Red Hill Creek, Indian Creek and Grindstone Creek relative to mean 1991-1992 Toronto tributary PCB concentrations (Boyd et al., 1999) Tributary Event- PCB type Concentration (ng/L) Etobicoke Creek Dry 3.7 Wet 19.1 Mimico Creek Dry Wet 12.4 Humber River Dry 1.2 Wet 6.7 Don River Dry Wet 11.2 Red Hill Creek Indian Creek Grindstone Creek

Dry Wet Dry Wet Dry wet

0.33 3.06 0.14 0.72 0.04 0.89

Notes: Although monitoring results for six tributaries were presented in Boyd et al. (1999), no PCB data were available for Highland Creek and Rouge River. For the 2007 event-based dataset in Hamilton Harbour, “dry” conditions represent n=1 (May 9, 2007), and “wet” conditions represent (n=5). Concentrations were calculated assuming <detection = 0 (i.e. minimum PCB concentrations).

3.3.2 PCB Loadings Estimated total PCB loadings to Hamilton Harbour during 2007 are summarized in Table 14. Sample size and temporal variability were too low to use a loading calculation method such as the Beale Ratio estimator. In addition, flow data from all sources during the 2007 sampling season are not known. As such, 2007 PCB loading estimates are cursory in nature; however, low, base case and high loading scenarios were estimated to provide a range of potential PCB loadings from each source in the absence of using more rigorous methods. The loading method used however is consistent with the end use of the data, that being relative loading comparisons and demonstration of potential PCB loadings to the Harbour from external sources. The estimated 2007 total PCB loading to Hamilton Harbour from all sources examined ranged from 213 g/year to <4,778 g/year, with a base case or best estimate of <1,027 g/year. Estimated total PCB loadings were highest from the Woodward Ave WWTP (<564 g/year), followed by the Desjardins Canal (<331 g/year). The other four sources examined (Skyway WWTP and 3 tributaries) each had estimated total PCB loadings ranging between <22 g/year (Grindstone Creek) to <47 g/year. Estimated total PCB loading was generally reflective of flow volumes. Hamilton Harbour Remedial Action Plan

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Table 14: Estimated low, base case and high PCB loads to Hamilton Harbour from six input sources

Woodward Ave WWTP

Flow (millions m3/year) (HH RAP, PCB concentration (ng/L)b PCB Loading (g/year) 2004)a Min Median Max Min Median Max Low Base High Case 111.95 117.05 146 1.05 <4.82 <24.19 118 <564 <3,532

Skyway WWTP Red Hill Creek

29.76 13.88

31.72 20.14

43.07 31.05

0.20 0.33

<1.12 <2.32

<1.39 <7.01

6.0 4.6

<36 <47

<60 <218

Indian Creek

13.88

20.14

31.05

0.14

<1.39

<1.6

1.9

<28

<50

Grindstone Creek

11.93

23.74

38.91

0.04

<0.93

<3.69

0.48

<22

<144

Desjardins Canal

46.87

79.10

151.19

1.76

<4.18

<5.13

82

<331

<776

213

<1,027

<4,778

Source

Total

Notes: a) For Woodward Ave and Skyway WWTPs, “Min” and “Median” represent the lowest and median total annual flow volume at each plant for 1996-2002 as shown in HH RAP (2004), while “Max” represents the design flow of 400 MLD and 118 MLD, respectively. For Red Hill Creek and Grindstone Creek flow, “Min”, “Median” and “Max” represent the lowest, median, and maximum total annual flow volume for 19962002 as shown in HH RAP (2004). For Indian Creek, flow was assumed equal to Red Hill Creek as no flow information was available. For Desjardins Canal, “Min”, “Median” and “Max” represent the lowest, median and maximum total annual flow volume for 1996-2002 as shown in HH RAP (2004), assuming flow into Cootes Paradise equal the flow leaving through the Desjardins Canal. b) For PCB concentration, “Min” represents the lowest detectable mean total PCB concentration of the six events as shown in Figure 12 and “min” column in Table 12; “Median” represents the median mean total PCB concentration of the six events as shown in “max” column in Table 12; “Max” represents the maximum mean total PCB concentration of the six events as shown in “max” column in Table 12.

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Total PCB loadings to Hamilton Harbour were estimated in this report to update previous loading estimates summarized in Labencki (2008). Side-by-side comparisons of previous PCB loading estimates from Labencki (2008) and updated 2007 PCB loading estimates (Table 14) are shown in Figure 15. Despite the differences in methods used to determine the previous and 2007 update PCB loading estimates, the updated loading estimates are remarkably close to previous loading estimates for all input sources and scenarios (low, base case, high). Two noteworthy exceptions are relative differences in PCB loading estimates from the Woodward Ave WWTP and Red Hill Creek for the “high” scenarios.

5

19.4 kg/year

20.8 kg/year Previous estimate (low)

PCB loads (kg/year)

4

2007 update (low) Previous estimate (base case) 2007 update (base case)

3

Previous estimate (high) 2007 update (high)

2

1

0 Woodward Ave WWTP

Skyway WWTP

Red Hill Creek

Grindstone Creek

Indian Creek

Desjardins Canal

Total

Figure 15: Previous and 2007 update of PCB loading estimates for input sources to Hamilton Harbour. Notes: Previous PCB loading estimates from Labencki (2008, p.22); 2007 update from Table 14.

Although it is difficult to make any definitive conclusions based on the small 2007 sample size and other caveats including differences in lab and field methods between studies, the Woodward Ave WWTP PCB loads were estimated at 19.4 kg/year for the previous “high” scenario (Labencki, 2008), and in the 2007 update, as 3.5 kg/year, a 82% decrease. The Red Hill Creek PCB loads were estimated at 0.589 kg/year for the previous “high” scenario (Labencki, 2008), and in the 2007 update, as 0.218 kg/year, a 63% decrease. Previous loading estimates outlined in Labencki (2008) were based on samples collected during 1988-1991 (Boyd, 2001), so the decrease in PCB loading estimates for these sources could possibly be reflecting a real temporal decline in PCB loads over the past two decades. Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

A potential decline in Woodward Ave WWTP PCB loadings may be due to a decrease in PCB inputs to the plant (Section 3.3.1 Total PCB Concentrations) following decreased PCB usage and the 1985 ban on direct discharge of PCB to the environment (Environment Canada, 2009). In addition, the City of Hamilton sewer use by-law 04-150 was amended in 2006 through by-law 06-228, which reduced the maximum allowable PCB concentration in sewer discharge from 5 ug/L to 1 ug/L, where discharge is permitted under other provisions of the by-law (City of Hamilton, 2006). The temporal decline in PCB loads to the WWTP is also supported by Harlow and Hodson’s supposition made in the 1980s that “a source of PCBs in the city, most likely in the industrial area, may contribute the majority [of PCB loads] to the WTP (Marsalek 1978)” (Harlow and Hodson, 1988, p.35) as stormwater loadings were calculated to account for only 5% of Shannon et al.’s (1976) WWTP influent loadings. Stormwater (i.e. urban runoff) loadings to the Woodward Ave WWTP may now account for a greater proportion of total WWTP influent loads relative to the 1970s and 1980s due to a likely decline in direct industrial loadings to the plant. The potential decline in PCB loadings from Red Hill Creek may be due to the mitigation of the Rennie and Brampton Street landfill sites undertaken in the early 2000s (City of Hamilton Public Works Department, 2008). A Harbour-wide temporal decline in incoming PCB loads is also evident when comparing the 2007 total Harbour and WWTP PCB loads to historical PCB loading estimates cited in the literature (Figure 16). The 1974 PCB loads to the Harbour from the Woodward Ave and Skyway WWTPs were estimated at 25.8 kg/year and <1.3 kg/year, respectively, and no total Harbour loading was provided (Shannon et al., 1976 in Harlow and Hodson, 1988). 60

Total Harbour load Woodward Ave WWTP load

PCB load (kg/year)

50

Skyway WWTP load

40

30

20

10 0.0355

0

n/a

0

1974

1982-1983

1989

0.004

1988-1991

2007

Figure 16: Temporal trends of estimated PCB loads to Hamilton Harbour. Notes: Sources of data are as follows: 1974: Shannon et al. (1976) in Harlow and Hodson (1988); 1982-1983: MOE (1985) except for Woodward Ave WWTP load which is an average of 4.6 kg/year from MOE (1985) and 4.0 kg/year from MOE (1987); 1989: HH RAP (1992a); 1988 – 1991: Labencki (2008) using data from Boyd (2001); 2007: base case values listed in Table 14. Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

The 1982-1983 total PCB load to the Harbour was estimated by MOE (1985) as 50 kg/year, with the total load from the Woodward Ave WWTP at 4.6 kg/year, from the Skyway WWTP at 0.9 kg/year, and from Red Hill Creek at 1.5 kg/year. The MOE (1985) report did not specify where the majority of the total Harbour PCB load of 50 kg/year was entering from but did allude to abnormally high PCB loadings from the Strathearne Avenue CSO as PCB concentrations ranged from 0.5 to 5 ug/L and were deemed “not typical of other outfalls, since it drains an area on which was previously located a transformer manufacturing plant” (MOE, 1985, p.31). Another 1982-1983 PCB loading estimate for the Woodward Ave WWTP was provided by MOE (1987) following an in-depth analysis of seasonal variation of influent and effluent contaminant concentrations at the plant. MOE (1987) estimated the 19821983 total PCB load to the Woodward Ave WWTP as 14.7 kg/year (i.e. influent load), and from the Woodward Ave WWTP to the Harbour as 4.0 kg/year (i.e. effluent load), a value consistent with the other 1982-1983 loading estimate of 4.6 kg/year (MOE, 1985). The difference between the PCB influent and effluent loads at the WWTP suggests that a large portion of the incoming PCB load ends up in the sludge fraction. Another relevant conclusion from this study was that “[a]lmost 75% of the influent polychlorinated biphenyls were concentrated in the solid phase of the wastewater [11.0 kg/year in solid fraction; 3.7 kg/year in liquid fraction], while on the contrary, 75% of the effluent PCB mass was concentrated in the liquid phase [1.1 kg/year in solid fraction; 2.9 kg/year in liquid fraction]” (MOE, 1987, p.59). As mentioned previously in Section 3.3.1 Total PCB Concentrations, this trend is in contrast to concentration trends as both influent and effluent concentrations at the Woodward Ave WWTP were driven by the solid phase (MOE, 1987, p.B-28). An implication of the shift from primarily solid phase loading in influent to primarily liquid phase loading in effluent may be a shift in the PCB congener profile between influent and effluent due to the association of more chlorinated PCBs with the particle phase; congener profiles are discussed in Section 3.3.3 PCB Congener Profiles. The 1989 total Harbour PCB loading estimate was 9.9 kg/year (27.2 g/day; HH RAP, 1992a, p.167). An important caveat to this historical PCB estimate is that the largest PCB sources to the Harbour (26%) were the combined sewer overflows (CSOs) at 2.6 kg/year (7.1 g/day), followed by the atmosphere at 2.6 kg/year (7.0 g/day), Lake Ontario inflow at 1.9 kg/year (5.2 g/day) and then the Woodward Ave WWTP at 1.6 kg/year (4.4 g/day). This means that the 2007 total Harbour loading estimate may not be directly comparable to earlier loading estimates as it does not account for other historically large PCB sources such as the atmosphere and CSOs; another caveat to inter-study comparison is that there are likely major differences and inconsistencies in methods used to estimate loads among studies. Nonetheless, despite the differences in sources examined and methods used, a decline in PCB loadings over time seems a reasonable supposition given the decline in active PCB use over the past several decades. Additional interpretation of PCB loadings can be made through comparison of Hamilton Harbour’s estimated tributary PCB loads to those calculated for other urban areas. Total PCB loadings for Toronto area tributaries in 1991-1992 ranged over two orders-of-magnitude from 55 g/year (152 mg/d) for the Rouge River to 1,683 g/year Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

(4612 mg/d) for the Humber River (Boyd et al., 1999). The estimated 2007 Hamilton Harbour tributary loads were similar in magnitude to Toronto tributaries at the lower end of the loading range (e.g. Rouge River) suggesting that estimates for the Red Hill Creek, Indian Creek and Grindstone Creek are in-line with the expected magnitude of urban tributary PCB loads. A caveat to this inter-study comparison is that PCB loads in Toronto tributaries have likely decreased since 1992. Additionally, tributary loads have not been standardized to load per unit area or flow which can identify anomalous loads as generally larger tributaries are expected to have a larger PCB load given a higher flow volume. More recent loading estimates for Toronto tributaries are lower relative to the Boyd et al. (1999) loading estimates, supporting the supposition of decreased PCB loads since 1992. Combined tributary loads in Toronto are currently estimated at < 1 kg/year, which works out to approximately 200 g/year per tributary on average (B. Gilbert, 2009, pers. comm.). Thus, the 2007 base case PCB loads for the Hamilton tributaries (Table 14) are approximately an order-of-magnitude lower than estimated Toronto tributary PCB loads; however, these estimates have not been standardized to flow.

3.3.3 PCB Congener Profiles PCB congener profiles from the WWTPs and tributaries were examined to determine any differences or anomalies in PCB profiles between the sources and/or between event types (Figure 17). A qualitative examination of the PCB profiles demonstrated that generally, differences in PCB congener signatures were evident between stations, and often times, between the different events sampled at a particular station. The PCB congener profiles typically observed at the WWTPs were enriched with less-chlorinated congeners, whereas the creeks - Red Hill Creek and the Desjardins Canal in particular, showed a stronger Aroclor 1254/1260 signature with higher proportions of more-chlorinated congeners. The travel blanks had a high proportion of less-chlorinated congeners not resembling any technical (Aroclor) mixture. Principle component analysis (PCA) was conducted on all the stations for each event sampled as well as Aroclor mixtures; results are shown in Figure 18(a-f). For most of the events monitored, samples from most of the stations clustered together demonstrating no clear anomalies in source signatures between stations. Also, for most events, samples did not cluster near any one Aroclor signature suggesting PCBs of mixed origins and the influence of weathering, fate and transport processes. There were however a few exceptions worth noting. Samples collected from the Woodward Ave WWTP and Skyway WWTP often clustered away from the other stations, and away from one another. This suggests that the nature of the PCB signature in effluent is different between the two WWTPs. This difference may be due to either differences in the nature of influent (i.e. different PCB Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

sources in sewershed), or may be due to differences in treatment processes between the WWTPs. Other anomalies are the August 8 (2nd replicate) and September 27 (both replicates) Grindstone Creek samples clustered away from the other stations; however, these anomalies were likely due to these samples approaching the detection limits of the PCB analysis.

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Hamilton Harbour Remedial Action Plan

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Woodward Ave WWTP

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2007 Field Season in Hamilton Harbour

8 6

Figure 17: PCB Congener profiles for WWTPs, tributaries, Desjardins Canal, travel blanks and Aroclor mixtures. Notes: PCB Congener profiles were created assuming congeners quantified at less than the detection limit were equal to the detection limit.

A1260 A1016 5 Mar14_900030002a Mar14_900030002b 2.5

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a) PCA plot for March 14, 2007 event; PC1 has eigenvalue of 80.9; % variance is 53.9; PC2 has eigenvalue of 37.4 and % variance of 24.9.

Hamilton Harbour Remedial Action Plan

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Event-based travel blanks

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2007 Field Season in Hamilton Harbour

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c) PCA plot for May 9, 2007 event; PC1 has eigenvalue of 63.69; % variance is 42.1; PC2 has eigenvalue of 42.3 and % variance of 28. Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

A1248g A1248a 9 A1254a

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d) PCA plot for August 8, 2007 event; PC1 has eigenvalue of 85.56; % variance is 46.1; PC2 has eigenvalue of 41.4 and % variance of 22.3.

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-9 A1260 -12 Component 1

e) PCA plot for September 11, 2007 event; PC1 has eigenvalue of 71.0; % variance is 52.7; PC2 has eigenvalue of 32.4 and % variance of 24.1. Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

A1254a

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f) PCA plot for September 27/28, 2007 event; PC1 has eigenvalue of 90.94; % variance is 56.7; PC2 has eigenvalue of 32.6 and % variance of 20.3. Figure 18: Principle Component Analysis (PCA) plots for WWTPs and tributaries relative to Aroclor mixtures during each event monitored in 2007. Notes: PCA was conducted on PCB signatures standardized to PCB congener % of total so samples could be compared against standard Aroclor signatures. PCA run in PAST.exe. Stations are identified by station numbers listed in Table 1.

Differences in PCB congener patterns were not only evident between stations, but also between event types at a particular station demonstrating temporal variability in PCB source signatures. PCA was conducted for the six events sampled at each station to further understand the sources of PCBs to the Harbour (Figure 19). Samples from the Woodward Ave WWTP demonstrated temporal variability in PCB source signature, with samples collected August 8 and September 28 demonstrating a stronger similarity to Aroclors 1016 and 1242 relative to the other events (Figure 19a). Reasons for changes in the PCB pattern between events remain unknown, as it does not appear to be correlated to changes in TSS concentrations (Table 7). It is important to note however that these two events were when the two highest total PCB concentrations were measured at the Woodward Ave WWTP in the 2007 dataset (Figure 12; Table 12). The temporal changes in PCB signature at the Woodward Ave WWTP may be due to changes in incoming PCB sources or changes in treatment processes at the plant, such as retention times which may have an impact on potential degradation (e.g. dechlorination). This latter point and its implications are discussed further below. Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

In contrast to the Woodward Ave WWTP, samples from the Skyway WWTP demonstrated little temporal variability in PCB signature (Figure 19b). This finding is consistent with the Skyway WWTP serving a separated sewer system, where the nature of the influent and hence effluent is likely more consistent relative to the Woodward Ave WWTP where the nature of influent changes pending storm events. Samples collected from Red Hill Creek were a mix of Aroclor patterns and relatively consistent in PCB congener signature, except for the spring freshet sample collected March 14, 2007 (Figure 19c). The March 14 sample showed a stronger influence of Aroclor 1260 relative to the other events, likely due to the high suspended sediment concentration observed during this event (Table 7) and the affinity that morechlorinated congeners have for particles. Samples collected from Indian Creek were also relatively consistent in their PCB congener signature among events, except for the second replicate collected September 11, 2007 (Figure 19d). Investigation of this sample revealed that this replicate had higher proportions of PCB congeners 18 and 28+33 for unknown reasons. Similar to Red Hill Creek, samples from Grindstone Creek were a mix of Aroclor patterns and were relatively consistent in PCB congener signature, except for the spring freshet sample collected March 14, 2007 (Figure 19e). The March 14 sample showed stronger influence of Aroclors 1254g and 1260 relative to the other events, likely due to the high TSS concentration observed during this event (Table 7). Also, as mentioned previously, the August 8 (2nd replicate) Grindstone Creek sample clustered away from the other events. This sample appeared to have an anomalously high proportion of PCB congener 4+10, although investigation into the raw data revealed that the absolute PCB 4+10 concentration was below the detection limit for this sample. Anomalous results for the August 8 (2nd replicate) sample appear to be caused by this sample approaching the detection limits of the PCB analysis and reflect an artefact of analysis methods. Samples collected from the Desjardins Canal during 2007 showed strong clustering, meaning the PCB congener pattern changed little between the events sampled (Figure 19f). One exception was the March 14, 2007 replicate samples which appeared to have a different signature relative to the other events; this may have been due to the relatively higher concentration of TSS observed during spring freshet (Table 7). PCB congener profiles were similar between replicate samples even when replicate samples had variability in total PCB concentration (e.g. April 27, September 27). Generally, samples from the Desjardins Canal showed a stronger similarity to Aroclors 1254g and 1260 relative to the other stations, which had higher proportions of lesschlorinated congeners

Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

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a) PCA plot for Woodward Ave WWTP events; PC1 has eigenvalue of 88.2; % variance is 56.8; PC2 has eigenvalue of 30.1 and % variance of 19.4.

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Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

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Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

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f) PCA plot for Desjardins Canal events; PC1 has eigenvalue of 75.3; % variance is 57.3; PC2 has eigenvalue of 32.1 and % variance of 24.6. Figure 19: Principle Component Analysis (PCA) plots for each WWTP and tributary station monitored demonstrating temporal variability in PCB signature during 2007. Notes: PCA was conducted on PCB signatures standardized to PCB congener % of total so samples could be compared against standard Aroclor signatures. PCA run in PAST.exe

Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

Of particular note in the 2007 event-based dataset were the unexpected PCB congener patterns observed in WWTP effluent and the implications of these signatures: the high proportions of less-chlorinated congeners, and the dissimilarity to typical Aroclor mixtures. The high proportions of di- and tri-chlorinated biphenyls in the WWTP effluent was not expected given the largest estimated PCB loading to the Harbour from the Woodward Ave WWTP and the strong Aroclor 1254g and 1260 signature observed in Hamilton Harbour sediment (Labencki, 2008), a signature inconsistent with one in WWTP effluent. Less-chlorinated congeners (i.e. di- and tri-chlorinated biphenyls) have relatively higher water solubility than more-chlorinated congeners, and therefore are more likely to exist in the dissolved-phase in effluent; a relatively low TSS concentration in WWTP effluent (Table 7) supports the supposition of the PCBs in WWTP effluent being primarily in the dissolved-phase. This has implications on the overall PCB loads to the Harbour as any reductions in suspended solids loadings from the WWTPs, as has been discussed for Woodward Ave WWTP in particular, may not have a significant impact on reducing overall PCB loads from the plant as originally postulated in Labencki (2008, p.28). Generally, the PCB congener patterns observed from the WWTPs, although enriched in less-chlorinated congeners, are not strongly similar to the less-chlorinated Aroclor mixtures such as Aroclor 1016 or 1242, although samples from the Woodward Ave WWTP on August 8 and September 28 showed stronger similarity to these technical mixtures relative to the other events (Figure 19a). One possible explanation for the unique PCB signature of WWTP effluent is dechlorination. Johnson et al. (2006) demonstrated that dechlorinated Aroclor 1254 is more similar to Aroclor 1242 than unaltered Aroclor 1254, which is interesting considering the historical use and presence of Aroclor 1254 in Hamilton Harbour (Harlow and Hodson, 1988; Labencki, 2008). PCB dechlorination can occur due to a number of processes which act to remove chlorine atoms from the biphenyl rings; one such process is biodegradation. Biodegradation can change a PCB congener signature in so much as higher proportions of congeners with ortho-positioned chlorines can be expected as ortho-chlorines are more resistant to biodegradation relative to para- or meta-positioned chlorine atoms (Field and Sierra-Alvarez, 2008). Although not conclusive evidence, it is an interesting observation that PCB congeners that are consistently high in Woodward Ave WWTP effluent are 4+10, 18, 28+33 and 31, all congeners with at least one ortho-chlorine atom on the biphenyl ring. Also supporting the presence of some form of dechlorination in the WWTP samples are the higher proportions of some congeners in WWTP effluent relative to their proportions in Aroclor mixtures. For example, in the August 8, 2007 samples from Woodward Ave WWTP, PCB 4+10 and PCB 18 were approximately 13% and 15% of the total PCB concentration, respectively, when these congeners are generally only found at a maximum of 4% and 11% in a standard Aroclor signature (Aroclor 1016), indicating that the WWTP PCB congener signature has been altered by one or more processes from a standard Aroclor profile. Further investigation of processes which determine the nature of the PCB congener pattern in WWTP effluent is challenging as much of the literature on dechlorination has focused on the microbial reductive dechlorination of PCBs in sediment (Bedard and Quensen, 1995). Also, the PCB congener profile of the WWTP Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

influent is not known, and the PCB congener signature of the waste stream may also be altered though physical-chemical processes and how operators at the WWTP process the waste water. For example, PCBs absorbed to particles may be removed as solids from the waste stream as sludge, and more water-soluble congeners (i.e. lesschlorinated congeners) would be more likely to flow through the liquid waste stream in the plant and be discharged in final effluent. As noted by Bedard and Quensen (1995), a “PCB congener distribution pattern in an environmental sample will present a record of all of the alteration processes to which that sample has been exposed (Brown and Wagner, 1990)” (Bedard and Quensen, 1995, p.133). A number of alteration processes are likely co-occurring at the WWTP to influence the unique PCB signature observed in final effluent during 2007, a supposition consistent with previous studies at the Woodward Ave which “support[ed] the conclusion that a combination of adsorption, biodegradation and volatilization mechanisms play a role in removal of [hazardous contaminants, including PCBs] at the Hamilton [waste water treatment plant]” (MOE, 1987, p.80). Finally, one last implication of the Woodward Ave WWTP PCB signature is that because it is enriched with less-chlorinated, more water-soluble PCB congeners, the receiving water downstream from the WWTP effluent may be an area of high potential pelagic exposure to PCBs. Less-chlorinated PCB congeners may be more bioavailable than more-chlorinated PCB congeners as the latter are more tightly bound to soils and sediment; however, less-chlorinated congeners are more readily metabolized and eliminated and subsequently may have relatively lower bioaccumulation (McFarland and Clarke, 1989). Thus, biological exposure to PCBs in Hamilton Harbour remains a complex issue and further study would be needed to more fully understand what role the WWTP effluent plays in PCB exposure relative to exposure obtained through PCBcontaminated sediments and biomagnification.

Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

4. Results and Discussion of In-Harbour Water Sampling 4.1 Total Suspended Solids (TSS) Replicate mean TSS concentrations for sampling conducted at Hamilton Harbour centre station (09 01 0258) and mid-Windermere Arm (09 01 0352) are presented graphically in Figure 20, and summarized quantitatively in Table 15. Variability within each set of replicate samples was generally low. The coefficient of variation (CV) was calculated for each replicate set of TSS concentrations (CV = standard deviation/mean), with a CV of zero signifying no difference between replicate samples. For the 2007 inHarbour dataset, CVs ranged from 0.016 (Mid-Windermere Arm, July 24, 2007; replicates: 4.4 mg/L, 4.5 mg/L) to 0.23 (Hamilton Harbour centre station, July 24, 2007; replicates: 5.0 mg/L, 3.6 mg/L) and had an overall median CV of 0.036. The low variability between replicate samples indicates minimal field and laboratory variability and increases confidence in the results. Travel blanks were not analyzed for TSS. 14

Apr 2 TSS concentration (mg/L)

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Figure 20: Mean replicate TSS concentrations measured at Hamilton Harbour centre station and mid-Windermere Arm on three sampling occasions during summer 2007. Notes: Error bars represent plus and minus one standard deviation of replicate samples.

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2007 Field Season in Hamilton Harbour

Table 15: Replicate mean TSS concentrations (mg/L) for in-Harbour sampling conducted during 2007. Station April 2 May 31 July 24 Median Hamilton Harbour centre 09 01 0258 7.9 3.6 4.3 4.3 station Mid-Windermere Arm 09 01 0352 12.1 4.2 4.5 4.5 Some temporal variability in TSS concentrations was observed for the in-Harbour sample dataset. TSS concentrations showed little variability between concentrations measured on May 31 and July 24; however, TSS concentrations were much higher on April 2 at both in-Harbour stations relative to concentrations observed at these stations on the other sampling occasions. The highest TSS concentration observed for the 2007 in-Harbour dataset was 12.1 mg/L measured at the mid-Windermere Arm station on April 2, 2007. One possible explanatory factor is that samples collected on April 2 were made following 8.8 mm of rain on April 1, whereas the May 31 and July 24 sampling events are considered â&#x20AC;&#x153;dryâ&#x20AC;? as they follow only trace amounts of rain in the previous few days (Appendix I). Spatial variability was also evident in the in-Harbour TSS concentrations as concentrations were consistently higher at the mid-Windermere Arm station relative to the Hamilton Harbour centre station, albeit the median concentrations were similar (4.5 and 4.3 mg/L, respectively). Further, while the median TSS concentrations in the inHarbour stations were similar to the median concentrations measured at the Woodward Ave and Skyway WWTPs (4.9 mg/L, 3.6 mg/L, respectively), they were much lower than the median concentrations measured at the tributaries (Red Hill Creek: 77.8 mg/L; Indian Creek: 22.9 mg/L; Grindstone Creek 12.4 mg/L). The median TSS concentration at the Desjardins Canal (32.5 mg/L) was about seven fold higher than the median TSS concentration at Hamilton Harbour centre station (4.3 mg/L), suggesting that Cootes Paradise may be a source of TSS to the Harbour via the Desjardins Canal. Results suggest an overall decreasing TSS concentration gradient from the tributaries to the Harbour. Results are in-line with expectations of the tributaries as primary (external) sources of TSS to Hamilton Harbour. There is no quantitative PWQO (MOEE, 1994) or CWQG (CCME, 2003) for TSS, although narrative criteria are available for turbidity. TSS was included in the 2007 Hamilton Harbour water sampling dataset primarily to assist in interpretation of PAH and PCB concentration results.

Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

4.2 Polycyclic Aromatic Hydrocarbons (PAHs) 4.2.1 Total PAH Concentrations Replicate mean Σ15PAH concentrations for the in-Harbour sampling conducted at centre station and mid-Windermere Arm are summarized in Table 16. Variability within each set of replicate samples was generally low. The coefficient of variation (CV) was calculated for each replicate set of PAH concentrations (CV = standard deviation/mean), with a CV of zero signifying no difference between replicate samples. For the 2007 in-Harbour dataset, CVs ranged from 0 (multiple stations) to 0.045 (Hamilton Harbour centre station, April 2, 2007; replicates: 199 ng/L, 212 ng/L) and had an overall median CV of 0.0019. The low variability between replicate samples indicates minimal field and laboratory variability and increases confidence in the results. All travel blanks had all 15 PAH compounds below their respective detection limits (Table 16; Appendix IV: PAH, PCB and TSS Analytical Methods), and as such, PAH concentration data were not blank corrected. Many of the 15 PAH compounds analyzed were below their respective detection limits for much of the 2007 sample dataset, particularly the higher molecular weight compounds. PAH concentration results in Table 16 represent an upper limit or maximum total PAH concentrations as results were tabulated assuming PAH compounds less than detection were equal to detection limits. As such, total Σ15PAH concentrations reported at or near 181 ng/L in Table 16 suggest relatively low PAH presence. A less conservative approach to estimating total PAH concentration is presented in Figure 21, whereby total PAH concentrations presented exclude PAH compounds that were not quantified above their respective detection limit. This latter approach represents the minimum total PAH concentration for each sample. Table 16: Replicate mean total Σ15PAH concentrations (ng/L) for in-Harbour sampling conducted during 2007. Station April 2 May 31 July 24 Median of all events Hamilton Harbour 09 01 0258 <206 <181 <181 <181 centre station Mid-Windermere Arm 09 01 0352 <510 <184 <210 <210 Travel blanksa See Table 6 <181 <181 <181 <181 Note: Concentrations represent an upper limit as any PAH compound reported by the lab as “less than detection” was assumed equal to its detection limit for purposes of calculating total PAHs. The sum of the detection limits for the 15 PAH compounds analyzed is 181 ng/L (Appendix IV). a – Single replicate only Hamilton Harbour Remedial Action Plan

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Detectable total PAH concentration (ng/L)

2007 Field Season in Hamilton Harbour

500

Apr 2 400

May 31 Jul 24

300

200

100

0 Hamilton Harbour centre station

Mid-Windermere Arm

Figure 21: Minimum mean total Σ15PAH concentrations (ng/L) measured at two inHarbour locations on three occasions during 2007. Notes: Error bars represent plus and minus one standard deviation of replicate samples. There is no error bar for mid-Windermere Arm July 24 sample as replicate samples had the same reported concentration (standard deviation = 0). “Detectable” total PAH concentrations refers to minimum PAH concentrations which were calculated through excluding PAH compounds that were not quantified above their respective detection limit.

Some temporal variability in PAH concentrations was observed for the in-Harbour sample dataset. Total PAH concentrations showed little variability between concentrations measured on May 31 and July 24; however, total PAH concentrations were much higher on April 2 at both in-Harbour stations relative to concentrations observed at these stations on the other sampling occasions. The highest total PAH concentration observed for the 2007 in-Harbour dataset was <510 ng/L measured at the mid-Windermere Arm station on April 2, 2007. One possible explanatory factor is that samples collected on April 2 were made following 8.8 mm of rain on April 1, whereas the May 31 and July 24 sampling events are considered “dry” as they follow only trace amounts of rain in the previous few days (Appendix I). A similar temporal pattern to that observed in Figure 21 was also observed for the in-Harbour TSS concentrations (Figure 20; Table 15), suggesting that TSS may be playing a role in ambient PAH concentrations in the Harbour. This is consistent with the finding of a relatively strong correlation between TSS and PAH at the Desjardins Canal during 2007 (Figure 10; 3.2.1 Total PAH Concentrations). Complicating the interpretation of PAH dynamics in the Harbour is that while the tributaries are a likely external source of TSS to the Harbour (4.1 Total Suspended Solids (TSS)), correlations Hamilton Harbour Remedial Action Plan

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between TSS and PAH were not strong in the tributaries for the events sampled during 2007, except for during spring freshet at Grindstone Creek (Figure 10; Section 3.2.1). A TSS-PAH correlation for the in-Harbour stations was not conducted due to the relatively high proportion of samples with PAH concentrations less than detection limits, and therefore, limited dataset. Spatial variability was also evident in the in-Harbour samples, as total PAH concentrations were consistently higher at the mid-Windermere Arm station (median: <210 ng/L) relative to Hamilton Harbour centre station (median: <181 ng/L). The relatively higher ambient total PAH concentration observed mid-Windermere Arm is consistent with the highest estimated PAH loads to the Harbour being from the Woodward Ave WWTP (Table 9), which are delivered to the Harbour via Windermere Arm. Further, the estimated total PAH loads to Windermere Arm from Woodward Ave WWTP and Red Hill Creek is 35 mg/year, whereas the estimated PAH load to the rest of the Harbour from the other four sources examined is 30.4 mg/year. Thus, given the smaller load (30.4 mg/year) to the larger main basin of the Harbour relative to the larger load (35 mg/year) to the smaller basin of Windermere Arm, higher ambient PAH concentrations in Windermere Arm relative to the main basin of the Harbour are expected due to lower dilution potential. These results are consistent with work conducted by the MOE in 2000 whereby higher water column PAH concentrations were observed in Windermere Arm relative to the main basin of the Harbour (Figure 2). Re-suspension of PAHs from Randle Reef sediment also contribute to ambient PAH concentrations in the waters of Hamilton Harbour, however; the 2007 results suggest that external PAH loading sources are an important determinant in ambient PAH concentrations in the water column of Hamilton Harbour. This conclusion is consistent with the PAH source apportionment work conducted by Sofowote et al. (2008), which determined that mobile sources of PAHs (e.g. diesel emissions, gasoline emissions) are an important contributor (~52 â&#x20AC;&#x201C; 61%) to PAH contamination in the Harbour and tributaries, relative to coal-derived PAH sources (~19 â&#x20AC;&#x201C; 26% ), which contribute to PAH contamination most at locations near Randle Reef. Important to note however is that work conducted by Sofowote et al. (2008) was for PAHs on suspended sediments, not whole water samples as examined in this study. Further to the discussion on potential PAH sources to the Harbour, another important observation is that median PAH concentrations in the Harbour (centre station: <181 ng/L; mid-Windermere Arm: <210 ng/L) are generally lower than those observed from the external PAH sources, namely the Woodward Ave WWTP (<240 ng/L) and the tributaries (Red Hill Creek: <295 ng/L; Indian Creek: <285 ng/L; Grindstone Creek <182 ng/L). The median total PAH concentration at the Desjardins Canal (<186 ng/L) was similar to the median PAH concentration at Hamilton Harbour centre station (<181 ng/L), suggesting that Cootes Paradise is not likely a prominent PAH source to Hamilton Harbour. Results are complex however, as Cootes Paradise appears to be a source of TSS to the Harbour (4.1 Total Suspended Solids (TSS)), and TSS and PAH at the Hamilton Harbour Remedial Action Plan

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Desjardins Canal are correlated (Figure 10). Further information on dissolved-phase PAHs relative to particle-phase PAHs at the Desjardins Canal would be necessary for further interpretation; however, it is likely that the water quality at the Desjardins Canal is primarily reflective of the Harbour, except for parameters where inputs from Cootes Paradise are significant relative to ambient conditions in the Harbour (e.g. TSS). Results suggest an overall decreasing PAH concentration gradient from WWTPs and tributaries to the Harbour, in-line with expectations of the WWTPs and tributaries as sources of PAHs to Hamilton Harbour.

4.2.2 PAH Compound Profiles

250

Apr 2 stn 258 rep average Apr 2 stn 352 rep average May 31 stn 352 rep average Jul 24 stn 352 rep average

200 150 100

DIBENZO(AH)ANTHRACENE

BENZO(G,H,I) PERYLENE

INDENO(1,2,3-CD) PYRENE

7,12DIMETHYL(B)ANTH'ENE

PERYLENE

BENZO (K) FLUORANTHENE

BENZO (B) FLUORANTHENE

BENZO(E)PYRENE

BENZO(A)PYRENE

CHRYSENE

BENZO(A)ANTHRACENE

FLUORANTHENE

PYRENE

0

ANTHRACENE

50 PHENANTHRENE

Detectable PAH concentration (ng/L)

PAH compound profiles from Hamilton Harbour centre station (09 01 0258) and mid-Windermere Arm (09 01 0352) were examined to determine any differences in PAH profiles between the two in-Harbour stations and/or between sampling occasions (Figure 22).

Figure 22: PAH compound profiles of water collected from Hamilton Harbour centre station and mid-Windermere Arm on three sampling occasions during summer 2007. Notes: PAH compound profiles from centre station (station 258) on May 31 and July 24, as well as all travel blanks could not be examined as all PAH compounds analyzed in these samples were below detection limits. PAH compounds are displayed by increasing molecular weight. â&#x20AC;&#x153;Detectableâ&#x20AC;? total PAH concentrations refers to minimum PAH concentrations which were calculated through excluding PAH compounds that were not quantified above their respective detection limit. Hamilton Harbour Remedial Action Plan

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For the replicate samples collected April 2, 2007 from Hamilton Harbour centre station, PAH compounds detected (in order of decreasing abundance) were: • pyrene (25, 30 ng/L), fluoranthene (13, 14 ng/L) and phenanthrene (<10, 17 ng/L). For the replicate samples collected from mid-Windermere Arm during 2007, PAH compounds detected (in order of decreasing abundance) were: • pyrene (210, 220 ng/L), fluoranthene (94, 110 ng/L), chrysene (28, 25 ng/L), benzo(a)anthracene (27, 24 ng/L), phenanthrene (15, 13 ng/L) and anthracene (<10, 21 ng/L) on April 2, 2007; • pyrene (11, 11 ng/L), fluoranthene (11, 11 ng/L) and phenanthrene (<10, 11 ng/L) on May 31, 2007; • fluoranthene (25, 25 ng/L) and pyrene (24, 24 ng/L) on July 24, 2007. Samples collected from mid-Windermere Arm had detection of a greater number of PAH compounds reflecting higher overall PAH concentrations in the water column of Windermere Arm relative to Hamilton Harbour centre station. As many of the 15 PAH compounds analyzed were below detection limits, particularly higher molecular weight compounds, and PAH compounds that were quantified were often at “trace” levels according to the laboratory analysis method, further quantitative analysis of PAH compound profiles for the in-Harbour water samples was not conducted. Qualitative analysis indicates that in Hamilton Harbour waters, generally the most abundant PAH compounds (in order of decreasing abundance) were pyrene, fluoranthene, and phenanthrene. These three PAH compounds were also the most abundant PAH compounds in the WWTP and tributary samples (3.2.3 PAH Compound Profiles); however, generally the most abundant PAH was fluoranthene followed by pyrene and phenanthrene, except for Indian Creek where fluoranthene was the most abundant followed by phenanthrene and pyrene. As with the tributary and WWTP PAH profiles, the PAH profiles in the Harbour reflect a complex interplay of abundance (e.g. direct atmospheric inputs, loads from incoming waters, internal PAH sources such as sediment resuspension) and fate/transport processes based on the physical-chemical properties of the PAH compounds. Further assessment and interpretation of the PAH profiles is challenging due to the detection limits used; the full PAH profiles are not known as the detection limit truncates PAHs found at lower ambient levels. Nonetheless, the PAH profile in the Harbour likely reflects urban runoff inputs delivered via Windermere Arm (3.2.2 PAH Loadings), supported by the observation of relatively higher PAH levels in mid-Windermere Arm relative to centre station. The large role of urban runoff is also supported by the source apportionment work by Sofowote et al. (2008), discussed earlier in this section. Further interpretation of PAH compound concentrations measured in the Harbour during 2007 can be made through comparison to relevant water quality guidelines such Hamilton Harbour Remedial Action Plan

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as the PWQOs (MOEE, 1994) or CWQGs (CCME, 2003). Comparison of ambient PAH concentrations to water quality guidelines is challenging however; as the analytical method used (MOE PAH3435; Appendix IV: PAH, PCB and TSS Analytical Methods) has detection limits for most of the PAH compounds close to or greater than the guidelines (3.2.3 PAH Compound Profiles; Table 10). Where quantifiable concentrations of PAH compounds were measured (i.e. greater than detection limits), PAH compound concentrations were compared to their respective PWQO and/or CWQG where guidelines exist. Generally, most exceedences of the PWQOs and/or CWQGs were observed for the April 2, 2007 sampling event at mid-Windermere Arm. For the water samples collected from the two in-Harbour stations on three occasions during the summer of 2007: • phenanthrene concentrations did not exceed the PWQO or CWQG; • anthracene concentrations exceeded the PWQO (but not the CWQG) on April 2 at mid-Windermere Arm; • pyrene concentrations exceeded the CWQG on April 2 at both centre station and mid-Windermere Arm; • fluoranthene concentrations exceeded the PWQO at both centre station and midWindermere Arm and on April 2, exceeded the CWQG at mid-Windermere Arm; • benzo(a)anthracene concentrations exceeded both the PWQO and CWQG on April 2 at mid-Windermere Arm; • chrysene concentrations exceeded the PWQO on April 2 at mid-Windermere Arm.

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4.3 Polychlorinated Biphenyls (PCBs) 4.3.1 Total PCB Concentrations Replicate mean concentrations for the in-Harbour sampling conducted at stations 258 and 352 are summarized in Table 17 following two methods (i.e. “min” and “max”) of estimating total Σ82PCB concentrations; results are presented graphically in Figure 23 following one method (i.e. “min”) of estimating total Σ82PCB concentrations. Variability within each set of replicate samples was generally low. The coefficient of variation (CV) was calculated for each replicate set of PCB concentrations, with a CV of zero signifying no difference between replicate samples. For the 2007 in-Harbour dataset, CVs ranged from 0.0068 (mid-Windermere Arm, July 24, 2007; replicates: <9.340 ng/L, <9.4296 ng/L) to 0.105 (mid-Windermere Arm, April 2, 2007; replicates: <23.9301 ng/L, <27.7658 ng/L) and had an overall median CV of 0.0535. Table 17: Replicate mean total Σ82PCB concentrations (ng/L) for in-Harbour sampling conducted during 2007. April 2 May 31 July 24 Median Station Min1 Max2 Min1 Max2 Min1 Max2 Min1 Max2 Hamilton 09 01 2.46 <2.66 3.11 <3.67 2.85 <3.43 2.85 <3.43 Harbour 0258 centre station Mid09 01 25.78 <25.85 4.81 <5.23 9.11 <9.38 9.11 <9.38 Windermere 0352 Arm Travel See 0.027 <0.31 0.0052 <0.57 0.034 <0.38 0.027 <0.38 3 blanks Table 6 Notes: 1 - “Min” or minimum PCB concentrations were calculated assuming any PCB congener reported by the lab as “actual result is less than the reported value” (i.e. less than detection) was equal to zero for purposes of calculating minimum total PCB concentration; this is a less conservative approach to estimating total PCB concentration from reported PCB congener concentrations. 2 - “Max” or maximum PCB concentrations represent an upper limit as any PCB congener reported by the lab as “actual result is less than the reported value” (i.e. less than detection) was assumed equal to its detection limit for purposes of calculating maximum total PCB concentration. 3 – Single replicates only

5

CVs were calculated based on “maximum” or upper limit total PCB concentrations (PCB congeners less than the detection limit were assumed equal to the detection limit). Hamilton Harbour Remedial Action Plan 68


Detectable total PCB concentration (ng/L)

2007 Field Season in Hamilton Harbour

30

Apr 2 25

May 31 Jul 24

20 15 10 5 0 Hamilton Harbour centre station

Mid-Windermere Arm

Figure 23: Replicate mean total Σ82PCB concentrations (ng/L) measured at two in-Harbour locations on three occasions during 2007. Notes: Error bars represent plus and minus one standard deviation of replicate samples. “Detectable” total PCB concentrations refers to minimum PCB concentrations which were calculated assuming any PCB congener reported by the lab as “actual result is less than the reported value” (i.e. less than detection) was equal to zero.

Travel blanks had low PCB concentrations and had a minimum concentration of 0.0052 ng/L on May 31, 2007 and a maximum, upper limit concentration of <0.57 ng/L on May 31, 2007 (Table 17). Most PCB congeners in the three travel blank samples were below their respective detection limits (Appendix IV: PAH, PCB and TSS Analytical Methods) and travel blank concentrations were approximately two orders of magnitude below sample concentrations; as such, sample PCB concentration data were not blank corrected. For the three in-Harbour surveys conducted during summer 2007, the highest total PCB concentration was measured at Hamilton Harbour centre station on May 31, 2007 (<3.67 ng/L), and at mid-Windermere Arm on April 2, 2007 (<25.85 ng/L). The highest concentration observed at centre station was however similar in magnitude to concentrations measured during the other two surveys at this station (2007 range: <2.66 ng/L - <3.67 ng/L), and also, similar in magnitude to concentrations measured at the Desjardins Canal (Table 12). In contrast to the consistency in total PCB concentrations observed at centre station, relatively large temporal variability was observed at the midWindermere Arm station. Total PCB concentrations at mid-Windermere Arm ranged five-fold between <5.23 ng/L on May 31, 2007, to <25.85 ng/L on April 2, 2007 (Table 17). Potential reasons for the large variability in PCB concentrations in mid-Windermere Arm were investigated, including antecedent weather conditions and associated TSS Hamilton Harbour Remedial Action Plan

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concentrations. Although not conclusive due to small sample size and a large number of other potential factors, antecedent wet weather conditions may have played a role in the high PCB concentrations observed April 2, 2007 at mid-Windermere Arm. The two days preceding the April 2 survey included 8.8 mm of rain (on April 1, 2007), whereas only 0.6 mm and no rain fell in the two days preceding the May 31 and July 24, 2007 surveys, respectively (Appendix I). Another potential factor in the large variability in PCB concentrations observed at the mid-Windermere Arm station is sediment resuspension and the role of TSS. Important to note is that no dredging was carried out April to July 2007 in Windermere Arm (M. Baxter, 2008, pers. comm.), thus any variability in TSS concentrations are likely due to ship traffic and storms rather than navigational dredging projects. As shown in Figure 20, TSS at mid-Windermere Arm was also highest on April 2 relative to the other surveys; however, TSS was also elevated at centre station on April 2 (Figure 23), a temporal pattern not reflected in the total PCB concentration results for this station. In order to investigate apparent inconsistencies between the TSS and total PCB spatial and temporal patterns, the 2007 in-Harbour total PCB concentrations were converted to a theoretical PCB suspended sediment concentration, which assumes all PCB measured in the water samples were bound to present TSS. The theoretical PCB suspended sediment concentrations ranged from 337 ng/g to 1,019 ng/g at centre station, and from 1,245 ng/g to 2,136 ng/g at mid-Windermere Arm (Table 18). For comparison, PCB concentrations in surface sediment at centre station range from 378 ng/g to 827 ng/g, and PCB concentrations in surface sediment in Windermere Arm range from 260 ng/g to 3,500 ng/g, with an area-average concentration of 1,270 ng/g (Labencki, 2008). Thus, the theoretical PCB suspended sediment concentrations appear to be slightly higher than surface sediment results for each respective station, although it is likely that not all PCB measured in the water samples were sediment-bound; some PCBs were likely in the dissolved-phase, which would make the theoretical PCB suspended sediment concentrations more in-line with measured surface sediment concentrations. This comparison suggests that resuspension of surface sediment is a plausible explanation for the in-Harbour PCB concentrations measured during 2007; however, it also remains plausible that theoretical PCB suspended sediment concentrations are higher than surface sediment PCB concentrations due to the presence of an uncharacterized PCB source. In order to further investigate these potential scenarios, in-Harbour water samples should be collected that distinguish between particle-bound and dissolved-phase PCBs, and/or in-Harbour water samples should be collected from the surface and bottom and subsequently be compared. If resuspension of surface sediment is a large driver in PCB water concentrations in Hamilton Harbour, then bottom water samples should have higher concentrations than surface samples. Hamilton Harbour Remedial Action Plan

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Table 18: Theoretical PCB suspended sediment concentrations at centre station and mid-Windermere Arm based on measured PCB and TSS concentrations during three surveys during 2007. Station Mean PCB conc. (ng/L) Centre 2.66 station Mid25.85 Windermere Arm

April 2 Mean Theoretical TSS PCB conc. suspended (mg/L) sediment conc. (ng/g) 7.9 337

3.67

May 31 Mean Theoretical TSS PCB conc. suspended (mg/L) sediment conc. (ng/g) 3.6 1,019

12.1

5.23

4.2

2,136

Mean PCB conc. (ng/L)

1,245

Mean PCB conc. (ng/L)

July 24 Mean Theoretical PCB TSS suspended conc. sediment conc. (mg/L) (ng/g)

3.43

4.3

798

9.38

4.45

2,108

Notes: PCB concentrations represent a maximum or upper limit as any PCB congener reported by the lab as â&#x20AC;&#x153;actual result is less than the reported valueâ&#x20AC;? (i.e. less than detection) was assumed equal to its detection limit for purposes of calculating maximum total PCB concentration.

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PCB concentrations in suspended sediment have been measured in the Harbour by Environment Canada, and at station 9033 - the mouth of Windermere Arm to the Harbour (between the mid-Windermere Arm and centre station) â&#x20AC;&#x201C; concentrations ranged from approximately 300 ng/g to 600 ng/g during 2004 (Labencki, 2008). Assuming all PCBs in water in the particle-phase and using the Environment Canada measured PCB suspended sediment concentrations, TSS concentrations would need to be between 40 and 80 mg/L to explain PCB concentrations of 24 ng/L in Windermere Arm. As the measured TSS concentrations in Windermere Arm were much lower than these theoretical values, data suggest a potentially large role of dissolved-phase PCB in the measured PCB concentrations in water, or potentially, the presence of PCBs in a non-aqueous phase. No obvious oil sheens or unusual conditions were recorded in the field notes along these lines however, that might explain the high PCB concentrations observed, particularly on April 2, 2007. Another interesting observation of the theoretical PCB suspended sediment concentrations is that concentrations were more variable at centre station (range of 3x) relative to mid-Windermere Arm (range of 1.7x). This trend is in contrast to that observed for total PCB concentrations in water (Table 17) as concentrations were more variable at mid-Windermere Arm (range of 5x) relative to centre station (range of 1.4x). Further interpretation of such trends is challenging without data on dissolved-phase versus particle-phase PCB concentrations in water, although intermittent loads of relatively cleaner sediment from the watersheds (e.g. Grindstone Creek) is a potential explanatory factor for relatively greater temporal variability in theoretical PCB suspended sediment concentrations at centre station. Despite the differences in temporal variability between the two in-harbour stations, spatial variability was also apparent between centre station and midWindermere Arm. The total PCB concentrations measured at mid-Windermere Arm were consistently higher than those observed at centre station, and on April 2, 2007, an order of magnitude higher. The higher PCB concentrations and temporal variability in Windermere Arm relative to centre station suggests the potential for a sporadic PCB source to Windermere Arm. This point is further emphasized by the observation of generally higher PCB concentrations in the Harbour waters relative to concentrations measured in WWTP effluent and in the tributaries (Figure 24). This finding supports what was previously believed to be contradictory results reported by Fox et al. (1996) and other studies which suggested higher PCB concentrations mid-Harbour relative to concentrations in incoming streams (Labencki, 2008). The holistic approach taken during 2007 to monitoring PCB concentrations in waters both to and within Hamilton Harbour revealed this very important observation on the state of PCBs in Hamilton Harbour and its watershed and may be important for potential remedial actions and management decisions.

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Mean PCB concentration (ng/L)

25

20

15

10

5

0

Woodward Avenue WWTP

Skyway WWTP

Red Hill Creek

Indian Creek

Grindstone Creek

Desjardins Canal

Hamilton MidHarbour Windermere centre station Arm

Figure 24: Mean PCB concentrations measured at all Hamilton Harbour stations monitored during 2007. Notes: Error bars represent plus and minus one standard deviation of events or surveys sampled. Mean PCB concentrations are minimum PCB concentrations which were calculated assuming any PCB congener reported by the lab as â&#x20AC;&#x153;actual result is less than the reported valueâ&#x20AC;? (i.e. less than detection) was equal to zero.

Further interpretation of the in-Harbour PCB concentrations was also conducted through comparison of the estimated standing stock of PCBs in the Harbourâ&#x20AC;&#x2122;s water column to estimated incoming PCB loads. Assuming a water volume of 2.8 x 1011 L, the (minimum) estimated standing stock of PCBs in the waters of Hamilton Harbour is 840 g to 1,400 g, assuming Harbour-wide average PCB concentrations of 3 ng/L to 5 ng/L, respectively. This standing stock is a minimum and likely higher than 840 g to 1,400 g due to PCB concentrations in Windermere Arm being much greater than main basin concentrations of 3 to 5 ng/L. As the standing stock of PCBs in the Harbour is similar to the estimated (base case) incoming annual PCB loads to the harbour of <1,027 g/year (Table 14), and the residence time of the Harbour is estimated to be less than one year, this suggests that PCBs in the Harbour water column are likely being supplied from a source not accounted for in Table 14, such as resuspension of contaminated sediment and/or an uncharacterized source of PCBs to the Harbour. Hamilton Harbour Remedial Action Plan

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Total PCB concentrations in the in-Harbour 2007 sample set were also compared to the PWQO of 1 ng/L (MOEE, 1994) for additional interpretation; there is no current CWQG for PCBs as “[e]nvironmental exposure is predominantly via sediment, soil, and/or tissue, therefore, the reader is referred to the respective guidelines for these media” (CCME, 2003, p.7). All in-Harbour water samples collected from centre station and mid-Windermere Arm during 2007 had total PCB concentrations greater than the PWQO of 1 ng/L; at mid-Windermere Arm, total PCB concentrations were over an order-of-magnitude greater than PWQO during the April 2 survey. Conversely, PCB concentrations in the tributaries sampled in 2007 were not routinely above the PWQO except for the Desjardins Canal station (3.3.1 Total PCB Concentrations), which further suggests a PCB issue in the Harbour relative to the inflow waters. Additional interpretation of 2007 in-Harbour PCB concentration results can also be made through comparison to concentrations measured in other studies, both earlier studies in Hamilton Harbour and studies on other relevant ambient waters. PCB concentrations in the ambient waters of the Harbour were monitored in 1982, although important to note is that analytical methods have greatly improved over the past few decades making interpretation of historical PCB concentration data somewhat challenging. Mean PCB concentrations in Hamilton Harbour surface waters during 1982 were less than the detection limit of 20 ng/L, and the maximum PCB concentration measured in the 1982 dataset was 30 ng/L (MOE, 1986). Further investigation of the 1982 raw data reveals that “[a]ll occurrences of PCB’s in 1982 were at stations 20 and 268” (MOE, 1986, p.12). As both these stations are located in Windermere Arm and were the only stations in the 1982 study to have PCB water concentrations above the detection limit of 20 ng/L, these data suggest that the spatial gradient observed in 2007 of higher PCB concentrations in Windermere Arm relative to the main basin of the Harbour, was also observed historically. In contrast to the 2007 dataset however, MOE (1986) reported higher PCB concentrations at Woodward Ave and Skyway WWTPs relative to the ambient waters in the Harbour. The reversing of this gradient from 1982 to 2007 may have several explanatory factors, including changes in analytical methods and other artefacts of analysis; however, it may also be due to changes in PCB sources to the Harbour over time or a temporal lag in the recovery of PCB concentrations in the Harbour. PCB concentrations were also monitored in 1984 at two stations in Windermere Arm – one near the mouth of Strathearne Slip (86 ng/L), and one near mid-Windermere Arm (213.7 ng/L) (Mudroch et al., 1989). PCB concentrations reported by Mudroch et al. (1989) were much higher than those reported in MOE (1986), which may be due to differences in methods used between studies, or due to high variability of PCB concentrations in Windermere Arm. Ambient PCB concentrations measured during 2007 were similar to historical results reported by MOE (1986), but were lower than historical results reported by Mudroch et al. (1989), making it challenging to discern any temporal trends in ambient PCB concentrations in the Harbour. Hamilton Harbour Remedial Action Plan

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In-Harbour PCB concentration results were also compared to ambient levels in the Great Lakes for further context. Anderson et al. (1999) reported ambient PCB concentrations in the Great Lakes ranging from 0.1 ng/L in Lake Superior to 1.6 ng/L in the western basin of Lake Erie. PCB concentrations in Hamilton Harbour are well above these ambient levels measured in other regions of the Great Lakes, and Windermere Arm in particular has PCB concentrations which are one to two orders-ofmagnitude above ambient Great Lakes concentrations.

4.3.2 PCB Congener Profiles PCB congener profiles from centre station and mid-Windermere Arm were examined to determine any differences or anomalies in PCB profiles between the stations and/or between surveys (Figure 25). Travel blank PCB congener profiles were also examined and did not resemble PCB profiles of the in-Harbour samples or Aroclor mixtures, suggesting minimal contamination of samples. In general, a qualitative examination of the in-Harbour PCB profiles demonstrated some minor differences in PCB congener signature between the two stations suggesting some spatial variability, and also between surveys at each station suggesting some temporal variability. The PCB congener profile observed at both centre station and mid-Windermere Arm showed a strong similarity to Aroclors 1254g and 1260, with some contribution of less-chlorinated PCB congeners. The presence of Aroclors 1254g and 1260 is consistent with the PCB signature found in Hamilton Harbour sediments (Labencki, 2008). Centre station generally had higher proportions of less-chlorinated congeners than mid-Windermere Arm. It remains to be determined if the presence of these lesschlorinated congeners is due to fate and transport processes such as desorption behaviour of PCBs from sediment (Achman et al., 1996), or due to external contributing sources such as the atmosphere or an uncharacterized source of PCBs. The prevalence of congeners 4+10, 18, and 28+33 in the samples from centre station and mid-Windermere Arm may be indicative of a source of Aroclor 1016 and/or 1242 as these congeners are found in high proportions in these technical mixtures. However, congener 8 â&#x20AC;&#x201C; also prevalent in Aroclors 1016 and 1242 â&#x20AC;&#x201C; is not found in high proportions in the samples, and the proportion pattern of congeners 4+10 through 28+33 does not match, suggesting that the presence of the less-chlorinated congeners in the in-Harbour samples may not be reflecting a technical mixture, but fate and transport processes instead. Explanatory factors for the presence of the lesschlorinated congeners remain inconclusive, and greater study is needed.

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April 2 (1)

May 31 (1)

14

6

Notes: PCB congener profiles were created assuming congeners quantified at less than the detection limit were equal to the detection limit.

The PCB congener profile remained relatively consistent at each station among surveys despite the differences in total PCB concentrations observed, however, the April 2 sampling event had slightly higher proportions of the more-chlorinated congeners, i.e. stronger Aroclor 1254g/1260 signature, and a noticeably higher proportion of congener 149 at mid-Windermere Arm. Also of note, the proportion of the less-chlorinated congeners increased from the April, to May, to July sampling occasions at centre station, suggesting that seasonality may play a role in the presence of these congeners, although this temporal pattern was not as evident at mid-Windermere Arm.

76

207

205

202

200

209 209

207

205

200

194

189

187

180+193

177

171

169

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The PCB congener pattern between centre station and mid-Windermere Arm was also reviewed on an absolute concentration basis (Figure 26) rather than a proportion of total basis (Figure 25). The absolute concentrations of the lesschlorinated congeners were similar between the two stations, and for the April 2 survey, higher at mid-Windermere Arm. Absolute concentrations of the more-chlorinated congeners were always higher at mid-Windermere Arm relative to centre station. This analysis suggests that Windermere Arm is a likely source area in the Harbour for the more-chlorinated congeners (i.e. A1254g/1260 signature), and could potentially be a source area for the less-chlorinated congeners as well. These results in conjunction with the higher proportion of less-chlorinated congeners at centre station relative to Windermere Arm may be indicating a relatively greater transport of less-chlorinated congeners than more-chlorinated congeners from Windermere Arm to centre station. Differential transport of less- versus more-chlorinated PCB congeners may be due to the differing physical-chemical properties between congeners, with the less-chlorinated congeners more likely to be measured in the dissolved phase, while the morechlorinated congeners more likely to be measured in the particle-phase, and transported via sediment loads.

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Principle component analysis (PCA) was conducted for both stations and all surveys relative to Aroclor mixtures; results are shown in Figure 27. For most of the surveys, samples from both stations clustered together demonstrating no clear anomalies in PCB source signatures between stations or between surveys. One exception was the April 2 survey at station 352 - samples clustered closer to Aroclor 1260 demonstrating the strong influence of this technical mixture on the observed PCB profile at this station during this survey. Hamilton Harbour Remedial Action Plan

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Figure 27: Principle component analysis (PCA) plot for PCB congener patterns observed at stations 258 and 352 during three 2007 surveys. Notes: PCA was conducted on PCB signatures standardized to PCB congener % of total so samples could be compared against standard Aroclor signatures. PCA run in PAST.exe

The PCB congener patterns observed at mid-Windermere Arm were compared to PCB profiles of potential sources, including in-situ surface sediment and water from Woodward Ave WWTP and Red Hill Creek. A qualitative comparison of the station 352 (mid-Windermere Arm) PCB congener profile in ambient water (collected in 2007) to the PCB congener profile in surface sediment (collected in 2003; Labencki, 2008) demonstrated a strong similarity between profiles (Figure 28), suggesting resuspension of in-situ surface sediment may be a relatively large source of PCBs to the water column in Windermere Arm.

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Figure 28: PCB congener profiles for water and sediment samples collected from station 352 (mid-Windermere Arm) in 2007 and 2003, respectively. Notes: PCB congener profiles of station 352 surface sediment sampled in 2003 are reported in Labencki (2008).

A PCA plot of the mid-Windermere Arm water samples and potential sources of PCBs to this station such as in-situ surface sediment, Woodward Ave WWTP effluent and water from Red Hill Creek, is shown in Figure 29. The May 31 and July 24 PCB profiles from mid-Windermere Arm were most similar to Red Hill Creek, and the April 2 PCB profiles from mid-Windermere Arm were most similar to in-situ surface sediment collected in 2003 (Labencki, 2008). Important to note however, is that water samples from Red Hill Creek had total PCB concentrations much lower than mid-Windermere Arm (Figure 24), suggesting that Red Hill Creek was not likely the primary source of PCBs to Windermere Arm despite some similarity in PCB signature. Further, while water samples from Woodward Ave WWTP had total PCB concentrations on par with those measured in Windermere Arm (Figure 24), the PCB signatures differed greatly between these stations, suggesting that Woodward Ave WWTP was not likely the primary driver behind high concentrations measured in Windermere Arm during 2007, despite Woodward Ave WWTP being the largest characterized source of PCB load to the Harbour (Table 14). Hamilton Harbour Remedial Action Plan

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Figure 29: Principle Component Analysis (PCA) plot for water samples collected during 2007 from mid-Windermere Arm (station 352), Woodward Ave WWTP (station 900030001), Red Hill Creek (station 900150007) and also for surface sediment samples collected during 2003 at mid-Windermere Arm (station 352). Notes: PCA was conducted on PCB signatures standardized to PCB congener % of total so samples could be compared against standard Aroclor signatures. PC1 has eigenvalue of 88.72; % variance is 62.7; PC2 has eigenvalue of 20.7 and % variance of 14.6. PCA run in PAST.exe PCB congener profiles of station 352 surface sediment sampled in 2003 are reported in Labencki (2008).

While there were some differences in PCB signature observed at midWindermere Arm among surveys, the strong similarity of the April 2 PCB profiles in water to the PCB profiles of in-situ surface sediment at station 352 is important as it was the April 2 survey which had considerably higher total PCB concentrations at station 352 relative to the other two surveys (Figure 23). As mentioned previously, these results suggest that sediment resuspension may be a large source of PCBs measured in water at station 352, however, an uncharacterized source also remains a possibility; these scenarios are consistent with the theoretical PCB suspended sediment results presented in Section 4.3.1 Total PCB Concentrations.. Hamilton Harbour Remedial Action Plan

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A PCA plot of water samples collected during 2007 from centre station and the Desjardins Canal is shown in Figure 30. Results show that while PCB congener profiles from these two stations are variable, they generally cluster together, providing a line-ofevidence that PCB concentrations measured at the Desjardins Canal and centre station are likely driven by similar sources.

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5. Results and Discussion of Sediment Sampling The sediment sample collected from the mouth of Grindstone Creek (station 09 15 0002) on August 8, 2007 had a total PCB concentration of 29 ng/g6, and a total organic carbon (TOC) concentration of 29 mg/g dry weight. The total PCB concentration was below the provincial sediment quality guideline (PSQG) lowest effect level (LEL) of 70 ng/g (MOE, 1993), and well below concentrations observed in the main basin of Hamilton Harbour (Labencki, 2008). Most PCB congeners analyzed (Appendix IV: PAH, PCB and TSS Analytical Methods) were below their detection limit and as such, a meaningful PCB congener profile or comparison to Aroclor patterns can not be conducted. Although only one sediment sample was collected from the mouth of Grindstone Creek and thus may not be representative of more widespread conditions, the low PCB concentration in sediment was consistent with the relatively low PCB concentrations measured in the waters of Grindstone Creek during 2007 (Figure 12). The low PCB concentration measured in the August 2007 sediment sample does not suggest a local PCB source at the mouth of the Grindstone Creek that would be an explanatory factor in elevated PCB concentrations observed in YOY fish in 2006 (Figure 3).

6. Conclusions Several important conclusions relevant to the HH RAP can be drawn from the 2007 Hamilton Harbour field season dataset. This dataset was compiled through eventbased sampling at the WWTPs and tributaries, three in-Harbour ambient water surveys, and a surface sediment grab sample from the mouth of Grindstone Creek. Important to note however, was that the summer of 2007 was unusually dry, and results may not be representative of typical event-based sampling conditions or long-term conditions and trends. The 2007 field season in Hamilton Harbour included sampling for both PAHs and PCBs, although the nature of issues differ between these two groups of chemicals. The consistent presence of PAHs in Harbour waters means chronic exposure of biota to these compounds and may have negative impacts on the health of the native fish populations. On the other hand, the presence of PCBs in Harbour waters, even if periodic in nature, is likely to result in bioaccumulation and biomagnification of these compounds in the aquatic food web, subsequently arising in restrictions on sport fish consumption to mitigate potential negative impacts on human health. While conclusions 6

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pertaining specifically to PAHs and PCBs are discussed separately below, there were some conclusions relevant to both chemical groups. For example, similar scales in temporal variability were observed between PAH and PCB concentrations in effluent at each WWTP examined. During 2007, effluent from Woodward Ave WWTP had relatively large fluctuations in both total PAH and PCB concentrations among events, but the Skyway WWTP had relatively consistent (and low) total PAH and PCB concentrations among events. These results suggest that the CSO system in Hamilton may play a significant role in PAH and PCB concentrations measured in effluent from the Woodward Ave WWTP, and hence load delivered to the Harbour. Also, in comparing spatial trends for the event-based sampling at the tributaries during 2007, differences in patterns between the PAH and PCB datasets reveal the different nature of the Hamilton Harbour watersheds. It was an interesting finding that Indian Creek and Red Hill Creek had similar PAH concentrations, but Red Hill Creek had consistently higher PCB concentrations than Indian Creek and Grindstone Creek, indicative of the different source areas for these two different chemical groups. While PAHs are relatively ubiquitous in the environment due to sources such as vehicular emissions, the presence of PCBs likely reflects historical use patterns; relatively higher PCB concentrations in tributaries such as Red Hill Creek are likely due to a stronger contribution of legacy sources. Another interesting spatial trend that differed between PAHs and PCBs was the contrasting Watershed-Harbour concentration gradient between these groups of chemicals. While PAH concentrations were generally higher at the WWTPs and in tributaries relative to ambient Harbour concentrations, the reverse was true for PCB concentrations, and considered an anomalous finding. Higher ambient PCB concentrations in the Harbour relative to incoming sources characterized is discussed further in Section 6.2 PCBs and Windermere Arm.

6.1 PAHs and Randle Reef PAHs will continue to be measured in the ambient waters of Hamilton Harbour even after the clean-up of Randle Reef due to ongoing PAH loads delivered from external sources. Sources such as the tributaries and the Woodward Ave WWTP, which serves a combined sewer system, integrate and subsequently convey multiple potential inputs, one of which is urban runoff. Based on the 2007 field results, the highest PAH loads to Hamilton Harbour were estimated to be from the Woodward Ave WWTP which are delivered to the Harbour via Windermere Arm; this is consistent with the highest ambient in-Harbour PAH concentrations being found in mid-Windermere Hamilton Harbour Remedial Action Plan

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Arm, relative to Hamilton Harbour centre station. In order to provide an in-depth evaluation of mass balance and/or background levels of PAH in Hamilton Harbour, lower analytical detection limits are needed for PAH analysis given the ambient PAH concentrations in the Harbour. However, if another PAH analytical method is not available, some PAH compounds may be good surrogate compounds for tracking relative PAH presence in waters samples, such as pyrene, fluoranthene or phenanthrene which were the three PAH compounds found in the highest abundance in the Woodward Ave WWTP, tributaries and in the Harbour. It should be noted that the PWQOs and often the CWQGs are routinely exceeded for the lower molecular weight PAHs analyzed in this study for event-based samples collected from Red Hill Creek and Indian Creek. PAH concentrations in the WWTPs, tributaries and in the Harbour are dynamic, likely demonstrating the influence of precipitation events on PAH concentrations measured in the watersheds and waters of Hamilton Harbour.

6.2 PCBs and Windermere Arm PCBs continue to be measured in input waters to Hamilton Harbour indicating that the presence of PCBs in the Harbour is not solely historical in nature. Of the eventbased sampling conducted at the WWTPs and tributaries during 2007, the highest PCB concentration and Harbour load was from the Woodward Ave WWTP. High temporal variability was also observed at the Woodward Ave WWTP, likely driven by CSO contribution to the plant during precipitation events. PCB concentrations and loads from the tributaries were generally highest during spring freshet, and lowest during baseflow. Some temporal variability was observed in the tributaries, a large degree to which can be related to TSS concentrations, as evidenced by high PCB and TSS concentrations during spring freshet. PCB congener profiles demonstrated differences between the stations examined. The PCB congener profile from the Woodward Ave and Skyway WWTPs was enriched in less-chlorinated congeners, and due to a lack of consistency with Aroclor mixtures, may be influenced by dechlorination within the plants. The tributaries generally showed a typical Aroclor 1254/1260 pattern, which was stronger during spring freshet when TSS concentrations were higher. The in-Harbour ambient water monitoring indicated that PCB concentrations at mid-Windermere Arm were consistently higher and temporally more variable than those measured at Hamilton Harbour centre station. During one of the surveys, PCB concentrations at mid-Windermere Arm were an order-of-magnitude higher than at Hamilton Harbour Remedial Action Plan

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centre station; such spatial trends suggest that Windermere Arm is a likely PCB source area to the main basin of the Harbour. Ambient PCB concentrations in Hamilton Harbour remain of concern as concentrations were consistently well above the PWQO and also, concentrations were well above those considered background and those measured in the incoming sources characterized (WWTPs, tributaries). The highest estimated PCB load to the Harbour delivered via Windermere Arm (i.e. Woodward Ave WWTP) is consistent with the highest ambient PCB concentrations (water, sediment) in the Harbour being measured in Windermere Arm. Results remain inconclusive however, as inflows characterized in 2007 do not seem to account for the in-harbour PCB concentrations measured. The PCB congener profile from Woodward Ave WWTP was not consistent with that measured in mid-Windermere Arm 2007 water and 2003 sediment samples, suggesting that Woodward Ave WWTP was not the major source of PCBs to Windermere Arm. The other potential source of PCBs to Windermere Arm - Red Hill Creek - was also not likely the major source of PCBs to Windermere Arm as total PCB concentrations measured in this tributary during 2007 were much lower than those measured in mid-Windermere Arm. Comparison of the total Harbour PCB loading estimate to the estimated standing stock of PCBs in the water column of Hamilton Harbour also suggests that PCBs are being supplied to the Harbour from source(s) other than those characterized in 2007. The 2007 results suggest that the inflow waters characterized do not represent anomalous PCB sources to Hamilton Harbour, and that a PCB source to the Harbour likely still remains that was not characterized during 2007. It remains unknown whether this potential PCB source(s) is an ongoing, locally-controllable source of PCBs; potential remaining PCB sources to the Harbour include resuspension, CSOs, or other, uncharacterized sources. Both event-based inputs and resuspension of contaminated sediment in Windermere Arm may be contributing PCBs to Hamilton Harbour and could be large drivers in the observed elevated PCB concentrations in Windermere Arm waters. Several lines-of-evidence suggest that stormwater inputs, likely delivered via CSOs, may be a major contributor of PCBs to Hamilton Harbour, and Windermere Arm in particular. Although the CSOs were not monitored in 2007, trends and observations at and between the Woodward Ave and Skyway WWTPs were used to interpolate what may be occurring in the Hamilton CSO system. PCB concentrations at the Woodward Ave WWTP (combined sewer system) were highest following a large storm event and were highly variable throughout the event-based sampling during 2007 in general; in contrast, PCB concentrations at the Skyway WWTP (separated sewer system) remained consistently low throughout 2007, suggesting variability in PCB concentrations at the Woodward Ave WWTP may be related to storm events. Additionally, the observed consistency in TSS concentrations in Woodward Ave WWTP effluent despite relatively high variability in PCB concentrations supports event-based PCB contributions to the plant. Temporal variability in total PCB concentrations in effluent likely reflects variability in PCB inputs to the waste water system, being detected in final effluent either as variable PCB particle concentrations or variable Hamilton Harbour Remedial Action Plan

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dissolved-phase PCB concentrations, as variability in TSS concentrations is not an explanatory factor. The likely role of event-based PCB contributions to Hamilton Harbour also includes lines-of-evidence extended to ambient conditions in the Harbour. High temporal variability in Windermere Arm PCB water concentrations was observed during 2007 which may be reflecting event-based PCB contributions. Although many of Hamiltonâ&#x20AC;&#x2122;s CSOs discharge indirectly or directly to Windermere Arm which may be a factor in this high variability, lines-of-evidence also suggest that episodic resuspension of in situ PCB-contaminated surface sediment may also be playing a large role in the elevated PCB water concentrations observed in Windermere Arm. For example, theoretical PCB suspended sediment concentrations - based on measured PCB and TSS concentrations - are consistent with surface sediment PCB concentrations, suggesting that resuspension is a possible driver of the elevated PCB concentrations in the water column. Additionally, the PCB congener profiles of water samples collected from mid-Windermere Arm in 2007 are consistent with surface sediment PCB congener profiles measured in 2003; the similarity between PCB signatures is even stronger when total PCB water concentrations are high at mid-Windermere Arm. Although both eventbased contributions and sediment resuspension may be playing a role in the PCB dynamics of Hamilton Harbour, it remains inconclusive as to what the dominant, controlling process or contribution is, and following this, how these processes relate to PCB concentrations in sport fish. Although monitored as part of the event-based dataset, PCB concentrations at the Desjardins Canal remained relatively consistent during 2007, and concentrations were higher than the other tributaries monitored but on par with concentrations measured in-Harbour. Results suggest either an uncharacterized PCB source to the Cootes Paradise area or that water at the Desjardins Canal is highly influenced by the waters of Hamilton Harbour; implications of each of these scenarios differ. Sampling of YOY fish was planned for 2007 due to elevated PCB concentrations observed during 2006, however, sampling was forfeited in 2007 as not enough YOY fish could be obtained to form a viable sample for PCB analysis. At one of the planned YOY fish sampling locations â&#x20AC;&#x201C; the mouth of Grindstone Creek â&#x20AC;&#x201C; a grab sediment sample was collected and demonstrated only trace levels of PCBs. Despite the very small sample size, these results suggested that elevated PCB concentrations in YOY fish during 2006 at this location were not likely due to a local PCB anomaly, but may be tied to more regional, Harbour-wide trends.

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7. Recommendations As follow-up to the sampling conducted in Hamilton Harbour during 2007, several recommendations have been formed to advance actions towards delisting the relevant BUIs under the Hamilton Harbour RAP. These recommendations include: 1. Use of an analytical PAH method with detection limits lower than MOE method PAH3435 should be employed if a more in-depth analysis of PAH concentrations in the tributaries and in the Harbour is required. Also, the detection limits for each PAH compound relative to its provincial water quality objective (PWQO) should be considered in choosing an appropriate method. Alternatively, determination of relative background PAH levels in the Harbour could potentially be examined through use of surrogate PAH compounds such as pyrene, fluoranthene or phenanthrene which were the three PAH compounds found in the highest abundance in the Woodward Ave WWTP, tributaries and in the Harbour. 2. All water, sediment, and suspended sediment PAH data for the Harbour collected by various agencies (e.g. Environment Canada) should be reviewed in conjunction with the source apportionment work undertaken by Sofowote et al. (2008). Review of these additional data and analyses can provide additional context regarding sediment and water column similarities, interactions, etc. for PAHs, and ultimately, lead to a better understanding of fate and transport of PAHs in Hamilton Harbour. 3. Follow-up field work and sampling should be conducted to determine if there is an active, locally-controllable source of PCBs to Hamilton Harbour, and if an active source is the primary driver behind elevated PCB water concentrations in Hamilton Harbour, relative to resuspension. Due to the anomalously high PCB concentrations measured in Windermere Arm water during 2007, subsequent investigations should focus spatially on Windermere Arm, although a Harbour-wide investigation should be completed for due diligence and the historical call for such actions. This recommended Harbour-wide PCB investigation into the potential presence of an active source should also focus on potential sources not investigated during 2007, that is, potential sources other than the Woodward Ave WWTP, Skyway WWTP, Red Hill Creek, Indian Creek and Grindstone Creek. A full literature review should be conducted for identification of potential PCB sources in the Hamilton Harbour watershed, and following this, the field investigation and sampling should include coverage of these potential sources. A combination of media should be used in the investigation, such as grab water samples and semi-permeable membrane devices (SPMDs); the former sample type has direct environmental relevance and meaning, while the latter allows for a time-integrated picture of conditions between sampling events. Hamilton Harbour Remedial Action Plan

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4. Follow-up field work and sampling should also be conducted to determine if resuspension of PCB-contaminated sediment is a primary driver behind elevated PCB water concentrations in Hamilton Harbour. In order to assist with such an investigation, it is recommended that at stations sampled in the Harbour-wide investigation for Recommendation #3, that paired water samples be collected from both the top of the water column, and near the sediment bed; these samples should be analyzed for both PCBs and TSS. Comparison of these paired samples at each station should reveal if PCB concentrations are correlated to TSS concentrations and if there is a PCB concentration gradient from the sediment bed towards the surface as a result of resuspension of PCB contaminated surface sediment. Additionally, measurement of the proportion PCBs in the dissolved-phase relative to the particle-phase in Harbour water samples should also assist in this investigation, as well as the investigation noted in Recommendation #3. 5. Follow-up field work and sampling should be conducted to determine if elevated PCB concentrations measured at the Desjardins Canal during 2007 represent flow from Hamilton Harbour, or an uncharacterized PCB source to Cootes Paradise. Although lines-of-evidence suggest that the water at the Desjardins Canal is likely from the Harbour (e.g. total PCB concentrations at the Canal are similar to Hamilton Harbour centre station, PCB congener profiles are similar between the Canal and Hamilton Harbour centre station), due diligence should be employed given the sensitive nature of Cootes Paradise, and the full Harbour-wide PCB investigation recommended above (Recommendation #3). This recommended local-scale PCB investigation into the potential presence of an active PCB source to Cootes Paradise should focus on eliminating potential PCB sources such as the Dundas WWTP, Spencer Creek and Chedoke Creek. A combination of media should be used in the investigation, such as grab water samples, SPMDs, and sludge samples from the WWTP. PCB concentrations in sludge samples collected from the Dundas, Woodward Ave and Skyway WWTPs could be compared to determine the relative presence of PCBs in each of the respective sewersheds; thus, the potential magnitude of PCB in effluent from the Dundas WWTP could be extrapolated given the known levels from the Woodward Ave and Skyway WWTPs measured during 2007. 6. YOY fish sampling should be re-attempted at the locations sampled in 2006 (Grindstone Creek, CCIW) to determine if elevated PCB YOY fish concentrations observed in 2006 represent an increasing trend in PCB exposure in Hamilton Harbour. 7. Follow-up actions to the 2007 field season should continue to be conducted in context to the relevant BUIs. Investigations designed to further understand the complex PCB dynamics in Hamilton Harbour will need to consider relationships to Hamilton Harbour Remedial Action Plan

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the BUI Restrictions on Fish and Wildlife Consumption, and how outcomes can be used towards restoration of the impaired beneficial use. For example, high PCB concentrations in water should be considered in terms of pelagic PCB exposure to fish relative to exposure obtained through biomagnification of PCBs acquired through the aquatic food chain from contaminated sediment. Implicit in this determination is the role of incoming PCBs in contamination of sediments relative to historical sediment contamination.

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8. References Achman, D.R., B.J. Brownawell and L. Zhang. 1996. Exchange of Polychlorinated Biphenyls Between Sediment and Water in the Hudson River Estuary. Estuaries. 19: 950-965. Anderson, D.J., Bloem, T.B., Blakenbaker, R.K., Stanko, T.A. 1999. Concentrations of Polychlorinated Biphenyls in the Water Column of the Laurentian Great Lakes: Spring 1993. Journal of Great Lakes Research. 25: 160-170. Bedard, D.L. and J.F. Quensen. 1995. Microbial Reductive Dechlorination of Polychlorinated Biphenyls. Wiley-Liss, Inc. Lily Y. Young, Chapter 4. ISBN 0471521094. Boyd, D. 2001. A summary of Contaminants in suspended sediment at sources to Hamilton Harbour, Technical Memorandum prepared for the Hamilton Harbour Remedial Action Plan, Environmental Monitoring and Reporting Branch, Updated July 2001. Boyd, D., Dâ&#x20AC;&#x2122;Andrea, M. and R. Anderton. 1999. Assessment of Six Tributary Discharges to the Toronto Area Waterfront. Volume 2: Technical Appendix and Data Summary. Report Prepared for the Toronto and Region Remedial Action Plan. May 1999. British Columbia Ministry of Environment (BC MOE). 1993. Polycyclic aromatic hydrocarbons. [online]. Available: http://www.env.gov.bc.ca/wat/wq/BCguidelines/pahs/pahs-01.htm#P249_7909 [May 29, 2009]. Canadian Council of Ministers of the Environment (CCME). 2003. Canadian water quality guidelines for the protection of aquatic life: Summary table. Updated December 2003. In: Canadian environmental quality guidelines, 1999, Canadian Council of Ministers of the Environment, Winnipeg. Canadian Council of Ministers of the Environment (CCME). 2001. Canadian sediment quality guidelines for the protection of aquatic life: Polychlorinated biphenyls (PCBs). Updated. In: Canadian environmental quality guidelines, 1999, Canadian Council of Ministers of the Environment, Winnipeg. City of Hamilton Public Works Department. 2008. Annual Monitoring Report - 2007 Rennie and Brampton Closed Landfill Sites. Final Report. March 2008. Hamilton Harbour Remedial Action Plan

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City of Hamilton. 2006. By-law no. 06-228. [Online]. Available: http://www.myhamilton.ca/myhamilton/CityandGovernment/CityDepartments/Publ icWorks/WaterAndWasteWaterDev/Sewer+Water/SewerByLaw.htm [July 23, 2009]. Environment Canada. 2009. Waste Management – PCB – Polychlorinated Biphenyls. [online]. Available: http://www.ec.gc.ca/drgdwrmd/default.asp?lang=En&n=75C647A7-1 [July 23, 2009]. Environment Canada. 2008. Daily Observation Data | Canada’s National Climate Archive. Hamilton A Station. [online]. Available: http://www.climate.weatheroffice.ec.gc.ca/climateData [May 20, 2009]. Field, J.A. and R. Sierra-Alvarez. 2008. Microbial transformation and degradation of polychlorinated biphenyls. Environmental Pollution. 155: 1-12. Fox, M.E., R.M Khan and P.A. Thiessen. 1996. Loadings of PCBs and PAHs from Hamilton Harbour to Lake Ontario. Water Qual. Res. J. Canada. Vol 31 (3): 593608 Gandhi, N. and M. Diamond. 2005 (unpublished). Preliminary Fate-Transport Modeling Results for Total PCB in Hamilton Harbour. February 4, 2005. Hamilton Harbour Remedial Action Plan (HH RAP) Technical Team. 2004. 1996-2002 Contaminant Loadings and Concentrations to Hamilton Harbour. ISBN 09733779-3-3. March 2004. Hamilton Harbour Remedial Action Plan (HH RAP). 1998. 1998 Status Report. ISBN 0662-27238-2. September 1998. Hamilton Harbour Remedial Action Plan (HH RAP). 1992a. Environmental Conditions and Problem Definition. Second Edition of the Stage 1 Report. ISBN 0-77780174-4. October 1992. Harlow, H.E. and P.V. Hodson. 1988. Chemical Contamination of Hamilton Harbour: A Review. Canadian Technical Report of Fisheries and Aquatic Sciences No. 1603. Fisheries and Oceans Canada. March 1988. Harner, T., and T. Bidleman. 1998. Octanol-air partition coefficient for describing particle/gas partitioning of aromatic compounds in urban air. Environmental Science and Technology. 32: 1494-1502. Hoffman, E.J., Mills, G.L., Latimer, J.S. and J.G. Quinn. 1984. Urban runoff as a source of polycyclic aromatic hydrocarbons to coastal waters. Environmental Hamilton Harbour Remedial Action Plan

91


2007 Field Season in Hamilton Harbour

Science and Technology. 18: 580-587. Johnson, G.W., Quensen, J.F., Chiarenzelli, J.R. and M.C. Hamilton. 2006. Polychlorinated Biphenyls in Environmental Forensics: Contaminant Specific Guide. By: Robert D. Morrison and Brian L. Murphy. Elsevier Science and Technology. Labencki, T. 2008. An Assessment of Polychlorinated Biphenyls (PCBs) in the Hamilton Harbour Area of Concern (AOC) in Support of the Beneficial Use Impairment (BUI): Restrictions on Fish and Wildlife Consumption. Written on behalf of the Hamilton Harbour Remedial Action Plan (HH RAP) Toxic Substances and Sediment Technical Team. August 2008. ISBN: 978-09810874-0-5 (Print Version), ISBN: 978-0-9810874-1-2 (Online Version). Labencki, T. 2004. Characterization of Washoff from Urban Impervious Surfaces. Master of Science thesis, University of Toronto. Marsalek, J. 1978. Polychlorinated biphenyls in surface runoff from two urban test catchments. CCIW unpublished report. McFarland, V.A. and J.U. Clarke. 1989. Environmental Occurrence, Abundance, and Potential Toxicity of Polychlorinated Biphenyl Congeners: Considerations for a Congener-Specific Analysis. Environmental Health Perspectives. 31: 225-239. Milani, D. and L.C. Grapentine. 2006. Application of BEAST sediment quality guidelines to Hamilton Harbour, an Area of Concern. Environment Canada. NWRI Contribution No. 06-407. Motelay-Massei, A., Harner, T., Shoeib, M., Diamond, M., Stern, G. and B. Rosenberg. 2005. Using passive air samplers to assess urban-rural trends for persistent organic pollutants and polycyclic aromatic hydrocarbons. 2. Seasonal trends for PAHs, PCBs, and organochlorine pesticides. Environmental Science and Technology. 39: 5763-5773. Mudroch, A., Onuska, F.I. and L. Kalas. 1989. Distribution of Polychlorinated Biphenylas in Water, Sediment and Biota of Two Harbours. Chemosphere. 18: 2141-2154. Ontario Ministry of the Environment and Energy (MOEE). 1994. Policies Guidelines Provincial Water Quality Objectives of the Ministry of Environment and Energy. Queenâ&#x20AC;&#x2122;s Printer for Ontario. July 1994. Ontario Ministry of the Environment (MOE). 1993. Guidelines for the Protection and Management of Aquatic Sediment Quality in Ontario. Queenâ&#x20AC;&#x2122;s Printer for Ontario. Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

August 1993. Ontario Ministry of the Environment (MOE). 1987. Removal of Hazardous Contaminants (HCs) in the Hamilton WPCP. Submitted to Water Resources Branch, Ontario Ministry of the Environment by Canviro Consultants Ltd. July 1987. Ontario Ministry of the Environment (MOE). 1986. Hamilton Harbour Trace Contaminants â&#x20AC;&#x201C; 1982-83 Loadings to, and Concentrations in the Harbour. Second Edition. Prepared by: D.J. Poulton. July, 1986. Ontario Ministry of the Environment (MOE). 1985. Hamilton Harbour Technical Summary and General Management Options. ISBN 0-7729-0706-4. August 1985. Shannon, E.E., Ludwig, F.J. and Valdmanis, I. 1976. Polychlorinated biphenyls (PCBs) in municipal wastewaters: An Assessment of the Problem in the Canadian Lower Great lakes. Canada-Ontario Agreement on Great Lakes Water Quality. Research Report No. 49. Sofowote, U.M, McCarry, B.E., and C.H. Marvin. 2008. Source Apportionment of PAH in Hamilton Harbour Suspended Sediments: Comparison of Two Factor Analysis Methods. Environmental Science and Technology. 42: 6007-6014. Water Survey of Canada. 2006. Real-Time Hydrometric Data. [online]. Available: http://scitech.pyr.ec.gc.ca/waterweb/disclaimerB.asp Zeman, A.J. and T.S. Patterson. 2003. Sediment survey of Windermere Arm, Hamilton Harbour. Environment Canada, National Water Research Institute, Burlington/Saskatoon, NWRI Contribution No. 03-171.

Hamilton Harbour Remedial Action Plan

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2007 Field Season in Hamilton Harbour

Appendix I: March – September 2007 weather conditions in Hamilton. Data from Hamilton A Station (43° 10.200' N, 79° 55.800' W), Environment Canada (2008).

Daily Data Report for March 2007 D a y

Max Min Temp Temp °C °C

01 -0.4 02 2.6 03 -0.2 04 -1.9 05 -2.7 06 -12.4 07 -7.4 08 -3.8 09 0.6 10 4.9 11 2.8 12 4.8 13 11.7 14 11.1 15 2.5 16 -2.7 17 0.4 18 0.7 19 2.3 20 -0.7 21 8.4 22 12.7 23 11.4 24 7.7 25 3.8 26 20.9 27 18.7 28 8.3 29 6.3 30 11.6 31 5.5 Sum Avg 4.1 Xtrm 20.9

-4.5 -0.7 -3.7 -4.5 -16.7 -21.7 -14.9 -13.2 -11.5 -3.0 -4.3 -5.8 2.5 1.6 -4.4 -6.8 -8.0 -8.6 -6.1 -7.6 -8.3 -0.1 0.1 0.9 0.2 1.6 7.8 0.2 -0.8 -3.1 1.5 -4.6 -21.7

Mean Temp °C -2.5 1.0 -2.0 -3.2 -9.7 -17.1 -11.2 -8.5 -5.5 1.0 -0.8 -0.5 7.1 6.4 -1.0 -4.8 -3.8 -4.0 -1.9 -4.2 0.1 6.3 5.8 4.3 2.0 11.3 13.3 4.3 2.8 4.3 3.5

Heat Deg Days °C 20.5 17.0 20.0 21.2 27.7 35.1 29.2 26.5 23.5 17.0 18.8 18.5 10.9 11.6 19.0 22.8 21.8 22.0 19.9 22.2 17.9 11.7 12.2 13.7 16.0 6.7 4.7 13.7 15.2 13.7 14.5 565.2

Cool Deg Days °C 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Total Rain mm 3.4 1.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.8 0.0 0.0 0.0 T 0.0 0.0 0.0 0.0 0.0 0.0 0.8 5.8 0.0 4.8 T 17.6 0.0 0.0 0.0 0.0 T 35.8

Total Snow cm 6.4 0.8 0.6 0.4 0.2 1.2 0.8 T 0.0 0.0 0.0 0.0 0.0 T T 5.2 4.6 0.2 0.4 T 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 20.8

Total Snow Precip on Grnd cm mm 9.8 2.4 0.4 0.4 0.2 0.8 0.8 T 0.0 1.8 0.0 0.0 0.0 T T 5.2 4.6 0.2 0.4 T 0.8 5.8 0.0 4.8 T 17.6 0.0 0.0 0.0 0.0 T 56.0

25 24 22 22 22 22 23 23 23 21 18 16 12 5 2 T 10 10 8 6 6 2 T T T T 0 0 0 0 0

Dir of Max Gust 10's Deg 6 22 23 25 29

Spd of Max Gust km/h 63 80 63 52 67 <31 <31 <31 <31 44 37 <31 <31 37 56 72 48 44 52 39 46 72 <31 32 35 52 39 50 43 <31 48

26 29

33 32 6 29 25 20 30 19 22 29 5 22 3 4 5 5

-0.2

Hamilton Harbour Remedial Action Plan

22

80 94


2007 Field Season in Hamilton Harbour

Daily Data Report for April 2007 D a y

Max Min Temp Temp °C °C

01 14.4 02 13.5 03 10.4 04 9.3 05 -3.8 06 -4.0 07 -1.4 08 -0.6 09 2.8 10 6.1 11 4.6 12 10.0 13 4.2 14 6.5 15 5.6 16 5.9 17 7.8 18 8.4 19 14.2 20 21.2 21 22.7 22 24.0 23 23.0 24 16.1 25 10.7 26 8.7 27 16.1 28 11.7 29 20.7 30 17.0 Sum Avg 10.2 Xtrm 24.0

2.5 3.6 -0.6 -4.0 -7.0 -7.3 -7.9 -5.4 -3.2 -3.5 -3.4 1.6 -2.4 -2.9 0.2 2.1 3.1 2.5 1.1 5.8 3.6 3.6 9.0 3.9 5.3 4.1 4.2 4.4 4.2 7.7 0.8 -7.9

Mean Temp °C 8.5 8.6 4.9 2.7 -5.4 -5.7 -4.7 -3.0 -0.2 1.3 0.6 5.8 0.9 1.8 2.9 4.0 5.5 5.5 7.7 13.5 13.2 13.8 16.0 10.0 8.0 6.4 10.2 8.1 12.5 12.4

Heat Deg Days °C 9.5 9.4 13.1 15.3 23.4 23.7 22.7 21.0 18.2 16.7 17.4 12.2 17.1 16.2 15.1 14.0 12.5 12.5 10.3 4.5 4.8 4.2 2.0 8.0 10.0 11.6 7.8 9.9 5.5 5.6 374.2

Cool Deg Days °C 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Total Rain mm 8.8 T 0.4 8.2 0.0 0.0 0.0 0.0 0.0 0.0 4.0 5.8 0.0 0.0 0.0 T 2.4 T 0.0 0.0 0.0 0.0 3.2 0.0 1.2 14.2 3.0 0.4 T 0.0 51.6

Total Snow cm 0.0 0.0 0.0 1.4 1.2 T 0.6 1.0 T T T T T 0.4 0.8 T 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5.4

Total Snow Precip on Grnd cm mm 8.8 T 0.4 9.4 1.2 T 0.6 1.0 T T 4.0 5.8 T 0.4 0.8 T 2.4 T 0.0 0.0 0.0 0.0 3.2 0.0 1.2 14.2 3.0 0.4 T 0.0 56.8

0 0 0 0 2 2 1 2 T T 0 0 0 0 T 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Dir of Max Gust 10's Deg 4 23 6 24 27 27 24 26

Spd of Max Gust km/h 35 48 63 67 57 52 46 41 <31 <31 70 56 59 33 46 63 <31 44 M <31 <31 41 89 <31 <31 54 44 <31 44 <31

5 25 26 4 4 34 7 M

22 22

4 23 22

5.5

Hamilton Harbour Remedial Action Plan

22*

89*

95


2007 Field Season in Hamilton Harbour

Daily Data Report for May 2007 D a y

Max Min Temp Temp °C °C

01 9.4 02 17.3 03 14.2 04 17.0 05 17.1 06 12.8 07 21.0 08 24.5 09 26.8 10 23.0 11 25.8 12 13.8 13 16.6 14 18.6 15 28.5 16 16.1 17 14.2 18 17.4 19 21.8 20 15.2 21 18.6 22 18.4 23 28.7 24 31.4 25 28.4 26 18.8 27 23.7 28 21.7 29 24.6 30 30.2 31 29.3 Sum Avg 20.8 Xtrm 31.4

5.1 3.3 5.0 3.9 6.4 3.6 1.2 6.0 12.2 12.5 10.3 7.3 3.8 3.7 15.6 6.5 4.4 2.9 3.9 4.5 2.9 8.8 9.7 14.5 14.9 12.5 11.1 6.9 8.0 12.1 15.6 7.7 1.2

Mean Temp °C 7.3 10.3 9.6 10.5 11.8 8.2 11.1 15.3 19.5 17.8 18.1 10.6 10.2 11.2 22.1 11.3 9.3 10.2 12.9 9.9 10.8 13.6 19.2 23.0 21.7 15.7 17.4 14.3 16.3 21.2 22.5

Heat Deg Days °C

Cool Deg Days °C

Total Rain mm

10.7 7.7 8.4 7.5 6.2 9.8 6.9 2.7 0.0 0.2 0.0 7.4 7.8 6.8 0.0 6.7 8.7 7.8 5.1 8.1 7.2 4.4 0.0 0.0 0.0 2.3 0.6 3.7 1.7 0.0 0.0 138.4

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.5 0.0 0.1 0.0 0.0 0.0 4.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.2 5.0 3.7 0.0 0.0 0.0 0.0 3.2 4.5 23.3

T 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 5.6 0.0 0.0 0.0 0.0 7.2 0.4 0.6 0.0 5.2 0.6 0.0 0.0 0.0 0.0 1.8 T 7.2 0.0 0.0 0.0 T 28.6

Total Snow cm 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Total Snow Precip on Grnd cm mm T 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 5.6 0.0 0.0 0.0 0.0 7.2 0.4 0.6 0.0 5.2 0.6 0.0 0.0 0.0 0.0 1.8 T 7.2 0.0 0.0 0.0 T 28.6

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Dir of Max Gust 10's Deg 4

Spd of Max Gust km/h 41 <31 35 39 46 44 <31 <31 <31 <31 35 48 <31 37 69 33 <31 <31 35 35 <31 <31 <31 33 48 <31 59 37 <31 <31 50

7 7 5 7

3 5 20 26 29

25 30

17 23 21 24

29

14.3

Hamilton Harbour Remedial Action Plan

26

69

96


2007 Field Season in Hamilton Harbour

Daily Data Report for June 2007 D a y

Max Min Temp Temp °C °C

01 26.8 02 30.4 03 24.9 04 22.8 05 17.2 06 18.1 07 28.6 08 30.7 09 22.5 10 25.4 11 27.0 12 31.2 13 30.4 14 23.0 15 26.4 16 28.8 17 30.0 18 31.0 19 29.0 20 23.3 21 26.9 22 22.6 23 24.0 24 28.4 25 31.4 26 33.0 27 33.0 28 27.7 29 25.3 30 26.0 Sum Avg 26.9 Xtrm 33.0S

16.5 14.7 16.6 15.6 7.4 8.3 8.4 12.1 7.9 9.9 12.0 16.0 18.2 14.8 12.3 12.5 16.3 13.7 15.1 11.0 13.4 9.7 6.2 10.8 14.0 15.2 20.0 13.5 11.1 9.7 12.8 6.2

Mean Temp °C 21.7 22.6 20.8 19.2 12.3 13.2 18.5 21.4 15.2 17.7 19.5 23.6 24.3 18.9 19.4 20.7 23.2 22.4 22.1 17.2 20.2 16.2 15.1 19.6 22.7 24.1 26.5 20.6 18.2 17.9

Heat Deg Days °C

Cool Deg Days °C

Total Rain mm

0.0 0.0 0.0 0.0 5.7 4.8 0.0 0.0 2.8 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.8 0.0 1.8 2.9 0.0 0.0 0.0 0.0 0.0 0.0 0.1 19.2

3.7 4.6 2.8 1.2 0.0 0.0 0.5 3.4 0.0 0.0 1.5 5.6 6.3 0.9 1.4 2.7 5.2 4.4 4.1 0.0 2.2 0.0 0.0 1.6 4.7 6.1 8.5 2.6 0.2 0.0 74.2

0.6 0.0 20.4 0.8 1.2 0.0 0.0 6.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 32.6

Total Snow cm 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Total Snow on Dir of Precip Grnd Max cm mm Gust 10's Deg 0.6 0.0 20.4 0.8 1.2 0.0 0.0 6.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 32.6

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Spd of Max Gust km/h <31 <31 32 <31 48 <31 43 93 <31 <31 <31 <31 32 44 <31 35 33 <31 41 43 52 41 <31 33 <31 <31 46 <31 <31 50

14 29 18 25

4 6 23 29 20 31 28 30 23

23

32

19.8

Hamilton Harbour Remedial Action Plan

25

93

97


2007 Field Season in Hamilton Harbour

Daily Data Report for July 2007 D a y

Max Min Temp Temp °C °C

01 21.2 02 24.0 03 26.0 04 20.4 05 28.5 06 28.4 07 29.6 08 27.9 09 33.3 10 32.5 11 25.0 12 26.3 13 23.7 14 23.4 15 24.9 16 27.2 17 24.8 18 27.1 19 29.6 20 24.3 21 25.5 22 27.4 23 26.7 24 23.6 25 27.0 26 28.6 27 26.1 28 29.4 29 28.1 30 30.3 31 33.1 Sum Avg 26.9 Xtrm 33.3

7.7 7.2 11.5 14.8 14.6 14.7 14.6 16.2 19.8 19.4 11.6 9.6 10.7 9.0 11.6 14.0 13.7 16.4 13.5 11.4 10.1 11.7 15.1 14.8 15.0 15.5 17.2 16.7 17.5 15.5 14.8 13.7 7.2

Mean Temp °C 14.5 15.6 18.8 17.6 21.6 21.6 22.1 22.1 26.6 26.0 18.3 18.0 17.2 16.2 18.3 20.6 19.3 21.8 21.6 17.9 17.8 19.6 20.9 19.2 21.0 22.1 21.7 23.1 22.8 22.9 24.0

Heat Deg Days °C 3.5 2.4 0.0 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.8 1.8 0.0 0.0 0.0 0.0 0.0 0.1 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 9.2

Cool Deg Days °C

Total Rain mm

0.0 0.0 0.8 0.0 3.6 3.6 4.1 4.1 8.6 8.0 0.3 0.0 0.0 0.0 0.3 2.6 1.3 3.8 3.6 0.0 0.0 1.6 2.9 1.2 3.0 4.1 3.7 5.1 4.8 4.9 6.0 82.0

0.0 0.0 0.0 9.8 3.8 0.0 0.0 0.6 2.6 0.0 0.0 9.0 0.0 5.0 0.0 0.0 0.0 0.0 5.6 0.0 0.0 0.0 0.6 T T 0.0 2.2 0.0 0.0 0.0 0.0 39.2

Total Snow cm 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Total Snow on Dir of Precip Grnd Max cm mm Gust 10's Deg 0.0 0.0 0.0 9.8 3.8 0.0 0.0 0.6 2.6 0.0 0.0 9.0 0.0 5.0 0.0 0.0 0.0 0.0 5.6 0.0 0.0 0.0 0.6 T T 0.0 2.2 0.0 0.0 0.0 0.0 39.2

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Spd of Max Gust km/h <31 <31 <31 <31 <31 35 37 39 48 48 48 69 32 54 32 <31 <31 <31 54 43 <31 <31 <31 <31 <31 37 <31 <31 <31 <31 <31

25 24 23 24 21 28 23 26 21 25

34 33

20

20.3

Hamilton Harbour Remedial Action Plan

23

69

98


2007 Field Season in Hamilton Harbour

Daily Data Report for August 2007 D a y

Max Min Temp Temp °C °C

01 34.2 02 34.8 03 33.9 04 28.8 05 27.3 06 30.4 07 25.6 08 30.7 09 21.0 10 29.6 11 29.3 12 28.8 13 28.6 14 27.3 15 27.3 16 29.6 17 26.8 18 23.0 19 21.4 20 17.8 21 19.6 22 25.7 23 28.9 24 31.4 25 26.2 26 24.9 27 26.5 28 29.1 29 32.2 30 24.6 31 26.1 Sum Avg 27.5 Xtrm 34.8

18.1 17.3 16.6 15.0 14.2 17.1 16.0 17.3 18.3 18.1 15.7 13.9 13.9 8.0 17.8 14.0 9.0 7.6 10.4 13.8 14.4 15.6 17.6 20.6 13.8 13.5 14.2 14.3 16.4 13.7 12.0 14.8 7.6

Mean Temp °C 26.2 26.1 25.3 21.9 20.8 23.8 20.8 24.0 19.7 23.9 22.5 21.4 21.3 17.7 22.6 21.8 17.9 15.3 15.9 15.8 17.0 20.7 23.3 26.0 20.0 19.2 20.4 21.7 24.3 19.2 19.1

Heat Deg Days °C 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.3 0.0 0.0 0.1 2.7 2.1 2.2 1.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 8.4

Cool Deg Days °C

Total Rain mm

8.2 8.1 7.3 3.9 2.8 5.8 2.8 6.0 1.7 5.9 4.5 3.4 3.3 0.0 4.6 3.8 0.0 0.0 0.0 0.0 0.0 2.7 5.3 8.0 2.0 1.2 2.4 3.7 6.3 1.2 1.1 106.0

0.0 0.0 T 0.0 T T 2.8 0.0 9.8 0.0 0.0 2.2 0.0 0.0 0.0 0.0 0.0 0.0 T 1.0 T T 8.4 5.8 11.0 0.0 0.0 0.0 0.0 0.0 0.0 41.0

Total Snow cm 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Total Snow Precip on Grnd cm mm 0.0 0.0 T 0.0 T T 2.8 0.0 9.8 0.0 0.0 2.2 0.0 0.0 0.0 0.0 0.0 0.0 T 1.0 T T 8.4 5.8 11.0 0.0 0.0 0.0 0.0 0.0 0.0 41.0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Dir of Max Gust 10's Deg

Spd of Max Gust km/h <31 32 33 <31 <31 <31 <31 32 <31 <31 <31 32 <31 32 <31 35 56 <31 <31 43 33 <31 37 63 54 <31 <31 <31 33 <31 <31

21 29

27

28 23 29 29

7 6 21 22 22

23

21.1

Hamilton Harbour Remedial Action Plan

22

63

99


2007 Field Season in Hamilton Harbour

Daily Data Report for September 2007 D a y

Max Min Temp Temp °C °C

01 23.3 02 26.6 03 29.6 04 26.7 05 24.5 06 33.9 07 31.2 08 28.7 09 19.6 10 23.3 11 20.5 12 19.2 13 21.2 14 27.2 15 14.6 16 17.5 17 20.5 18 23.1 19 26.2 20 24.6 21 27.8 22 25.6 23 24.2 24 28.2 25 31.6 26 22.0 27 17.0 28 19.7 29 20.5 30 22.2 Sum Avg 24.0 Xtrm 33.9

12.5 10.8 11.2 11.1 16.3 13.2 19.8 17.5 14.9 12.0 10.7 8.8 7.2 10.0 2.6 1.2 5.2 9.0 11.6 14.0 14.5 9.4 5.3 9.5 15.4 14.4 11.3 9.2 4.8 8.6 10.7 1.2

Mean Temp °C 17.9 18.7 20.4 18.9 20.4 23.6 25.5 23.1 17.3 17.7 15.6 14.0 14.2 18.6 8.6 9.4 12.9 16.1 18.9 19.3 21.2 17.5 14.8 18.9 23.5 18.2 14.2 14.5 12.7 15.4

Heat Deg Days °C

Cool Deg Days °C

Total Rain mm

0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.7 0.3 2.4 4.0 3.8 0.0 9.4 8.6 5.1 1.9 0.0 0.0 0.0 0.5 3.2 0.0 0.0 0.0 3.8 3.5 5.3 2.6 55.2

0.0 0.7 2.4 0.9 2.4 5.6 7.5 5.1 0.0 0.0 0.0 0.0 0.0 0.6 0.0 0.0 0.0 0.0 0.9 1.3 3.2 0.0 0.0 0.9 5.5 0.2 0.0 0.0 0.0 0.0 37.2

0.0 0.0 0.0 0.0 T 0.0 1.6 0.0 9.4 0.0 5.8 0.0 0.0 8.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 20.0 6.2 1.2 0.0 0.0 52.6

Total Snow cm 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Total Snow on Dir of Precip Grnd Max cm mm Gust 10's Deg 0.0 0.0 0.0 0.0 T 0.0 1.6 0.0 9.4 0.0 5.8 0.0 0.0 8.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 20.0 6.2 1.2 0.0 0.0 52.6

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Spd of Max Gust km/h <31 <31 <31 <31 <31 48 67 <31 39 <31 56 33 <31 57 44 <31 <31 <31 <31 <31 <31 39 <31 <31 48 <31 <31 43 <31 <31

20 21 5 28 26 21 32

26

23

29

17.4

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67

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Appendix II: Grindstone Creek hydrographs for 2007 Hydrographs from Water Survey of Canada (2006) for Grindstone Creek station at Aldershot (WSC station 02HB012). Approximate sampling times are indicated.

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Appendix III: Field photographs taken during 2007 Photos taken March 14, 2007 (Spring Freshet)

Red Hill Creek (station 09 15 0007) â&#x20AC;&#x201C; March 14, 2007

Red Hill Creek (station 09 15 0007)â&#x20AC;&#x201C; March 14, 2007 Hamilton Harbour Remedial Action Plan

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Red Hill Creek (station 09 15 0007) – March 14, 2007 – looking upstream

Red Hill Creek (station 09 15 0007) – March 14, 2007

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2007 Field Season in Hamilton Harbour

Indian Creek (station 09 15 0003) – March 14, 2007 – looking downstream

Indian Creek (station 09 15 0003) – March 14, 2007 – looking upstream

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2007 Field Season in Hamilton Harbour

Indian Creek (station 09 15 0003) – March 14, 2007 – at weir

Grindstone Creek (station 09 15 0009) – March 14, 2007 – looking upstream

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2007 Field Season in Hamilton Harbour

Grindstone Creek (station 09 15 0009) – March 14, 2007 – Water Survey of Canada sampling station hut

Desjardins Canal (station 09 15 0008) – March 14, 2007 – at fish gate

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Desjardins Canal (station 09 15 0008) â&#x20AC;&#x201C; March 14, 2007

Desjardins Canal (station 09 15 0008) â&#x20AC;&#x201C; March 14, 2007

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Photos taken August 8, 2007 (following small rain event)

Red Hill Creek (station 09 15 007) – August 8, 2007 – looking south (upstream)

Red Hill Creek (station 09 15 0007) – August 8, 2007 – looking north (downstream)

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2007 Field Season in Hamilton Harbour

Red Hill Creek (station 09 15 0007) – August 8, 2007 – Collection of a water sample

Indian Creek (station 09 15 0003) – August 8, 2007 – looking north

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2007 Field Season in Hamilton Harbour

Indian Creek (station 09 15 0003) – August 8, 2007 – looking south

Indian Creek (station 09 15 0003) – August 8, 2007 – looking north at weir

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2007 Field Season in Hamilton Harbour

Footpath to Indian Creek (station 09 15 0003) – August 8, 2007 - Wardley Park

Grindstone Creek (station 09 15 0009) – August 8, 2007 – looking upstream

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Mouth of Grindstone Creek at Hamilton Harbour – August 8, 2007 – where “Grindstone Creek” young-of-the-year (YOY) fish were sampled in 2006

Mouth of Grindstone Creek – August 8, 2007 – looking out towards Hamilton Harbour

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2007 Field Season in Hamilton Harbour

Mouth of Grindstone Creek – August 8, 2007 – observation of algae

Mouth of Grindstone Creek – August 8, 2007 – observation of algae

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Mouth of Grindstone Creek – August 8, 2007 – collection of sediment sample GL077155

Mouth of Grindstone Creek – August 8, 2007 – homogenization of sediment sample GL077155

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2007 Field Season in Hamilton Harbour

Mouth of Grindstone Creek – August 8, 2007 – identification of Grindstone Creek watershed via signage

Desjardins Canal (station 09 15 0008) – August 8, 2007

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Appendix IV: PAH, PCB and TSS Analytical Methods 15 PAH compounds and their detection limits (ng/L) as analyzed through MOE method PAH3435: Test Code

PAH Compound name

Detection limit

PNANTH PNBAA PNBAP PNBBFA PNBEP PNBKF PNCHRY PNDAHA PNDMBA PNFLAN PNGHIP PNINP PNPERY PNPHEN PNPYR

ANTHRACENE BENZO(A)ANTHRACENE BENZO(A)PYRENE BENZO (B) FLUORANTHENE BENZO(E)PYRENE BENZO (K) FLUORANTHENE CHRYSENE DIBENZO(AH)ANTHRACENE 7,12-DIMETHYL(B)ANTH'ENE FLUORANTHENE BENZO(G,H,I) PERYLENE INDENO(1,2,3-CD) PYRENE PERYLENE PHENANTHRENE PYRENE

10 20 1 10 10 10 10 20 10 10 20 20 10 10 10

Total

/181

82 PCB congeners analyzed through MOE method PCB3459: Test Code

PCB Congener name

PCBTOT PCX001 PCX003 PCX006 PCX008 PCX015 PCX016 PCX018 PCX019 PCX022 PCX031 PCX037

PCB CONGENER TOTAL 2-MONOCHLOROPCB(1) 4-MONOCHLOROPCB(3) 2,3'-DICHLOROPCB(6) 2,4'-DICHLOROPCB(8) 4,4'-DICHLOROPCB(15) 2,2',3-TRICHLOROPCB(16) 2,2',5-TRICHLOROPCB(18) 2,2',6-TRICHLOROPCB(19) 2,3,4'-TRICHLOROPCB(22) 2,4',5-TRICHLOROPCB(31) 3,4,4'-TRICHLOROPCB(37)

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PCX040 PCX041 PCX044 PCX049 PCX052 PCX054 PCX060 PCX066 PCX070 PCX074 PCX077 PCX081 PCX084 PCX085 PCX087 PCX095 PCX097 PCX099 PCX104 PCX105 PCX110 PCX114 PCX118 PCX119 PCX123 PCX126 PCX128 PCX135 PCX137 PCX138 PCX141 PCX149 PCX151 PCX155 PCX156 PCX157 PCX158 PCX167 PCX168 PCX169 PCX170 PCX171 PCX174 PCX177

2,2',3,3'-TETRACHLOROPCB(40) 2,2',3,4-TETRACHLOROPCB(41) 2,2',3,5'-TETRACHLOROPCB(44) 2,2',4,5'-TETRACHLOROPCB(49) 2,2',5,5'-TETRACHLOROPCB(52) 2,2',6,6'-TETRACHLOROPCB(54) 2,3,4,4'-TETRACHLOROPCB(60) 2,3',4,4'-TETRACHLOROPCB(66) 2,3',4',5-TETRACHLOROPCB(70) 2,4,4',5-TETRACHLOROPCB(74) 3,3',4,4'-TETRACHLOROPCB(77) 3,4,4',5-TETRACHLOROPCB(81) PECLPCB(84)+(90)+(101) 2,2',3,4,4'-PENTACHLOROPCB(85) 2,2',3,4,5'-PENTACHLOROPCB(87) 2,2',3,5',6-PENTACHLOROPCB(95) 2,2',3',4,5-PENTACHLOROPCB(97) 2,2',4,4',5-PENTACHLOROPCB(99) 2,2',4,6,6'-PENTACHLOROPCB(104) 2,3,3',4,4'-PENTACHLOROPCB(105) 2,3,3',4',6-PENTACHLOROPCB(110) 2,3,4,4',5-PENTACHLOROPCB(114) 2,3',4,4',5-PENTACHLOROPCB(118) 2,3',4,4',6-PENTACHLOROPCB(119) 2',3,4,4',5-PENTACHLOROPCB(123) 3,3',4,4',5-PENTACHLOROPCB(126) 2,2',3,3',4,4'-HEXACHLOROPCB(128) 2,2',3,3',5,6'-HEXACHLPCB(135) 2,2',3,4,4',5-HEXACHLOROPCB(137) 2,2',3,4,4',5'-HEXACHLOROPCB(138) 2,2',3,4,5,5'-HEXACHLOROPCB(141) 2,2',3,4',5',6-HEXACHLOROPCB(149) 2,2',3,5,5',6-HEXACHLOROPCB(151) 2,2',4,4',6,6'-HEXACHLOROPCB(155) 2,3,3',4,4',5-HEXACHLOROPCB(156) 2,3,3',4,4',5'-HEXACHLOROPCB(157) 22'33'45(129)+233'44'6-HXCLPCB (158) 2,3',4,4',5,5'-HEXACHLOROPCB(167) 22'44'55'(153)+23'44'5'6-HXCLPCB (168) 3,3',4,4',5,5'-HEXACHLOROPCB(169) 2,2',3,3',4,4',5-HEPTACHLOROPCB (170) 2,2',3,3',4,4',6-HEPTACHLOROPCB (171) 2,2',3,3',4,5,6'-HEPPCB(174) 2,2',3,3',4',5,6-HEPTACHLOROPCB (177)

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PCX178 PCX183 PCX187 PCX188 PCX189 PCX191 PCX193 PCX194 PCX199 PCX200 PCX201 PCX202 PCX203 PCX205 PCX206 PCX207 PCX208 PCX209 PCX233 PCX410

2,2',3,3',5,5',6-HEPTACHLOROPCB (178) 2,2',3,4,4',5',6-HEPTACHLOROPCB (183) 2,2',3,4',5,5',6-HEPTACHLOROPCB (187) 2,2',3,4',5,6,6'-HEPTACHLOROPCB (188) 2,3,3',4,4',5,5'-HEPTACHLOROPCB (189) 2,3,3',4,4',5',6-HEPTACHLOROPCB (191) 22'344'55'(180)+233'4'55'6-HPCLPCB (193) 2,2',3,3',4,4',5,5'-OCTACHLOROPCB (194) 2,2',3,3',4,5,5',6'-OCTACHLOROPCB (199) 2,2',3,3',4,5,6,6'-OCTPCB(200) 2,2',3,3',4,5',6,6'-OCTACHLOROPCB (201) 2,2',3,3',5,5',6,6'-OCTACHLOROPCB (202) 2,2',3,4,4',5,5',6-OCTACHLOROPCB (203) 2,3,3',4,4',5,5',6-OCTACHLOROPCB (205) 22'33'44'55'6-NONACHLOROPCB(206) 22'33'44'566'-NONACHLPCB(207) 22'33'455'66'-NONACHLOROPCB(208) DECACHLOROPCB(209) 244'-TRICLPCB(28)+2'34-TRICLPCB (33) 2,2'-DICHLOROPCB(4)+2,6-DICHLPCB (10)

Note: detection limits for PCB congeners under method PCB3459 are sample-specific.

55 PCB congeners analyzed through MOE method PCB3412: Test Code

PCB Congener Name

PCB018 PCB019 PCB022 PCB028 PCB033 PCB037 PCB044 PCB049 PCB052 PCB054 PCB070 PCB074 PCB077 PCB081 PCB087 PCB095

2,2',5-TRICHLOROBIPHENYL 2,2',6-TRI(CL)BIPHENYL 2,3,4'-TRICHLOROBIPHENYL 2,4,4'-TRICHLOROBIPHENYL 2',3,4-TRICHLOROBIPHENYL 3,4,4'-TRICHLOROBIPHENYL 2,2',3,5'-TETRACHLOROBIPHENYL 2,2',4,5'-TETRACHLOROBIPHENYL 2,2',5,5'-TETRACHLOROBIPHENYL 2,2',6,6'-TETRA(CL)BIPHENYL 2,3',4',5-TETRACHLOROBIPHENYL 2,4,4',5-TETRACHLOROBIPHENYL 3,3',4,4'-TETRACHLOROBIPHENYL 3,4,4',5-TETRACHLOROBIPHENYL 2,2'3,4,5'-PENTACHLOROBIPHENYL 2,2'3,5',6-PENTACHLOROBIPHENYL

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PCB099 PCB101 PCB104 PCB105 PCB110 PCB114 PCB118 PCB119 PCB123 PCB126 PCB128 PCB138 PCB149 PCB151 PCB153 PCB155 PCB156 PCB157 PCB158 PCB167 PCB168 PCB169 PCB170 PCB171 PCB177 PCB178 PCB180 PCB183 PCB187 PCB188 PCB189 PCB191 PCB194 PCB199 PCB201 PCB202 PCB205 PCB206 PCB208

2,2'4,4',5-PENTACHLOROBIPHENYL 2,2'4,5,5'-PENTACHLOROBIPHENYL 2,2'4,6,6'-PENTA(CL)BIPHENYL 2,3,3'4,4'-PENTACHLOROBIPHENYL 2,3,3'4',6-PENTACHLOROBIPHENYL 2,2'3,4,5'-PENTACHLOROBIPHENYL 2,3'4,4',5-PENTACHLOROBIPHENYL 2,3'4,4',6-PENTACHLOROBIPHENYL 2'3,4,4',5-PENTA(CL)BIPHENYL 3,3'4,4',5-PENTACHLOROBIPHENYL 22',33',44'-HEXA(CL)BIPHENYL 2,2'3,44'5'-HEXACHLOROBIPHENYL 2,2'3,3'46'-HEXACHLOROBIPHENYL 2,2'3,5,5'6-HEXA(CL)BIPHENYL 22',44',55'-HEXACHLOROBIPHENYL 22',44',66'-HEXA(CL)BIPHENYL 2,3,3'4,4'5-HEXACHLOROBIPHENYL 2,3,3'44'5'-HEXACHLOROBIPHENYL 2,3,3'4,4'6-HEXACHLOROBIPHENYL 23',44',55'-HEXA(CL)BIPHENYL 23',44',5'6-HEXA(CL)BIPHENYL 3,3'4,4'55'-HEXACHLOROBIPHENYL 22'33'44'5-HEPTA(CL)BIPHENYL 22'33'44'6-HEPTA(CL)BIPHENYL 22'33'4'56-HEPTA(CL)BIPHENYL 22'33'55'6-HEPTA(CL)BIPHENYL 22'344'55'-HEPTACHLOROBIPHENYL 22'344'5'6-HEPTA(CL)BIPHENYL 22'34'55'6-HEPTA(CL)BIPHENYL 22'34'566'-HEPTA(CL)BIPHENYL 233'44'55'-HEPTA(CL)BIPHENYL 233'44'5'6-HEPTACHLOROBIPHENYL 22'33'44'55'-OCTACHLOBIPHENYL 22'33'455'6'-OCTA(CL)BIPHENYL 22'33'45'66'-OCTA(CL)BIPHENYL 22'33'55'66'-OCTA(CL)BIPHENYL 233'44'55'6-OCTACHLOBIPHENYL 22'33'44'55'6-OCTACHLOBIPHENYL 22'33'455'66'NONA(CL)BIPHENYL

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MOE Method SS3188 (P. Wilson, 2008, pers. comm.) Principle of Method Suspended Solids refers to all material (residue, particulate) which is removed from a sample when a well-mixed sample aliquot is filtered through a 1.5 to 2.0 µm glass fibre filter. The material on the filter is dried at 103 ±2°C. When relatively large aliquots or whole samples are used the sample aliquot may be transferred to the filtering apparatus via a graduated cylinder. Alternatively, for smaller volumes a transfer or graduated pipette can be used. Suspended Solids is calculated after weighing the dried material (residue) using the following equation: Suspended Solids (mg/L) = (C- D) x 106 V where: C = the weight (g) of the filter plus residue D = the weight (g) of the filter V = volume (mL) of sample Sample Requirements Samples may be collected in plastic or glass containers and refrigerated at 5°C ±4°C. No preservatives should be added. Ideally, a container of sample solely for Suspended Solids should be submitted, to ensure adequate volume. Samples should be analyzed as soon as possible. The sample holding time is up to 14 days. Note: An amount of 200 mL is required for most samples; however, 500 mL is required when a visual estimate shows low Suspended Solids (3-15 mg/L). Shortcomings Interferences Oils and greases inhibit evaporation to a constant weight.

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Hamiltonharbourfieldseasonassessment,labencki,2007  

http://www.hamiltonharbour.ca/resources/documents/HamiltonHarbourFieldSeasonAssessment,Labencki,2007.pdf