Risk Management of a Small Craft Harbour in British Columbia

Transcription

1 Risk Management of a Small Craft Harbour in British Columbia LIZANNE MELOCHE GOLDER CHRIS MCDONALD FISHERIES AND OCEANS CANADA 10 May 2018

2 OUTLINE Small Craft Harbour Management 01 Tool for Liability Estimation at SCHs 02 Case Study - Risk Management of a remote SCH in BC 03 Establishing Harbour Authorities 04 Questions 05

3 Small Craft Harbour s goal is a sustainable national network of safe and accessible harbours that are: fully operational in good working condition managed and maintained by selfsufficient harbour authorities that represent the interests of users and communities Fisheries and Oceans Canada Small Craft Harbours Across the country SCH operates and maintains approximately 1015 Harbours 721 of these are considered to be Core Harbours. Core Harbours: Harbours managed by a Harbour Authority and are critical to the Fishing Industry. 3

4 Harbour Management Challenges HARBOUR MANAGEMENT CONTAMINATED SITES Small Craft Harbours are often located in small remote communities where: Management and maintenance of the Harbour can be a challenge. Harbour Authority and management is not clearly defined. Harbours can become a dumping ground for both local and transient users of the facility. Common contaminated sites issues at Small Craft Harbours include: Waste dumping in the inter- and subtidal zones (commonly including batteries, boats, engines, fuel tanks and bottles lots of bottles) Boat maintenance deposit of metals, solvents, paint into the intertidal. Creosote treated pilings that, although considered a beneficial use, contribute PAH contamination to the waterlot. 4

5 Contaminated Sites The general goal for contaminated sites management at Small Craft Harbours includes: Identifying suspected areas of contamination, sampling those areas to confirm if contamination is present, Establishing a liability, and Working to eliminate that liability via remediation, risk assessment or risk management. 5

6 Liability Estimation Tool for Small Craft Harbours MARCH 2016 Objective to develop a transparent and consistent approach to estimate liabilities for Small Craft Harbour (SCH) Sites in BC Tool was developed and applied to rank six SCH sites in coastal BC Applied to sites with limited data, provides high level liability estimate Relied on guidance in Risk Based Strategy for the Assessment and Management of Environmental Contamination at Fisheries and Oceans Canada SCHs Management considerations: SCHs are commercial facilities, similar in terms of physical setting and site activities, higher degree of risk tolerance 6

7 Conceptual Site Model Small Craft Harbours Boat maintenance (metals, PAHs, PHCs, TBT) Poor quality fill (metals, PAHs, PHCs) Stormwater outfall (metals, PAHs, PHCs) Boat grid (metals, TBT) Wharf Infrastructure (PAHs, metals) Moored vessels on wharf/floats or shoreline (metals, PAHs, PHCs) Debris under wharf/floats (metals, PAHs, PHCs) Contaminant Sources receptors Surface Runoff a a Leaching Groundwater Transport Leaching a. Fish and birds are considered as receptors if biomagnyfing COPCs are identified 7

8 Liability Estimation for SCHs CATEGORIZATION OF SITES Available chemistry data were screened against low threshold and high threshold screening values Sites were categorized as negligible to low, moderate, or high risk based on the number and magnitude of exceedances Negligible to low risk sites: did not warrant future action (COPC below their respective thresholds) Moderate risk: recommended for risk assessment/risk management (exceedances were lower magnitude and/or not widespread) High risk: recommended for physical remediation (for costing purposes) 8

9 Liability Estimation for SCHs COSTING AND RESULTS Standardized costs assigned for risk assessment Weight of evidence approach assumed for ecological receptors Tissue samples added if biomagnifying contaminants identified Human Health Risk Assessment added if contamination identified in intertidal area Dredging costs estimated based on area exceeding upper threshold Used some parameters from sediment costing tool developed by Golder (FCSAP costing tool) Assumed transport of sediment to waste facility via tug boat and covered scow Overall reduction in liabilities at all six sites using this approach versus previous methods 9

10 Case Study SMALL CRAFT HARBOUR COASTAL BC SCH located in a remote community in coastal BC (population of approx. 400) A sediment investigation and risk assessment were conducted in 2016 as a first step to determine whether physical remediation was warranted and if so, to what extent. The risk assessment consisted of an aquatic weight of evidence assessment and a human health risk assessment 10

11 Case Study - Risk Assessment SUMMER 2016 FIELD PROGRAM Field work conducted August Co-located samples collected for chemistry, toxicity, and benthic taxonomy to support the weight of evidence assessment Intertidal sediment samples collected for the human health risk assessment Auxiliary parameters also measured as indicators of bioavailability (e.g. AVS, SEM, TOC). Grabs were difficult to obtain in some locations debris noted in underwater camera footage Intertidal sediment sample collection Co-located samples for chemistry, toxicity, and benthic community 11

12 Case Study Risk Assessment HUMAN HEALTH RISK ASSESSMENT HHRA evaluated risks to recreational receptors of all ages using the SCH for swimming or wading Sediment data were screened against soil quality guidelines protective of human health to select contaminants of potential concern (COPCs) No COPCs were identified in the intertidal data risks were considered acceptable for the intertidal zone Ingestion of suspended sediment while swimming was retained as a potential exposure pathway for metals and PAHs in subtidal sediments Based on the calculated exposure doses under a conservative exposure scenario, risks were considered acceptable for swimmers. Swimmers at the SCH August

13 Case Study - Risk Assessment AQUATIC WEIGHT OF EVIDENCE ASSESSMENT Aquatic risk assessment evaluated risks to benthic invertebrates as the primary ecological receptors as they are in direct contact with sediment at all times A weight-of evidence (WOE) approach was used: Sediment chemistry: Comparison to BC sediment criteria, bioavailability considered in evaluation Toxicity 20 day survival and growth using a marine polychaete Benthic Community Abundance, Richness, Diversity Lines of evidence assigned weightings a priori Comparisons made to a reference station Assessment Endpoint: Maintain a healthy benthic community that is productive and diverse and able to support fish and wildlife 13

14 Case Study - Risk Assessment AQUATIC WEIGHT OF EVIDENCE ASSESSMENT 20-day survival and growth of the marine polychaete Neanthes arenaceodentata Sample ID Survival (%) (Mean ± SD) Control 100 ± 0.0 SE015 (reference) 100 ± 0.0 SE ± 8.9 SE ± 8.9 SE ± 11.0 SE ± 0.0 SE ± 0.0 Average Individual Dry Weight (mg) (Mean ± SD) 12.8 ± ± 1.5* 9.9 ± 1.9* 11.2 ± ± 1.5* 11.0 ± ± 2.7* Sediment Toxicity Line of Evidence Results: No significant effect on mortality Some minor effects to growth in one sample (sulphide was elevated at test initiation in porewater at both reference and SE006 potential confounding factor) * Statistically significant reduction in endpoint compared to control 20-50% reduction compared to reference, but not statistically significant 14

15 Case Study - Risk Assessment AQUATIC WEIGHT OF EVIDENCE Benthic Community Line of Evidence Results: Station Total Abundance Total Richness SE015 (reference) SE SE SE %-50% reduction compared to reference SE015 >50% reduction compared to referencese015 SE SE %-50% reduction compared to reference SE015 >50% reduction compared to referencese015 SE015 was considered an appropriate reference sample for comparison SE003, % reduction in abundance or richness, but all major taxa groups present SE004, 006, 009 > 50% reduction, abundance highly impacted Grain size and TOC not very different between reference and WOE samples, not likely confounding factor 15

16 Case Study - Risk Assessment AQUATIC WEIGHT OF EVIDENCE ASSESSMENT WOE results suggested a low to moderate risk for benthic invertebrates within the waterot Impacts were not correlated with contamination Risks were driven by impacts to benthic community at some locations near the wharf structure more likely attributable to presence of debris (e.g. habitat alteration) Physical remediation of sediment not recommended Recommended removal of debris 16

17 Case Study - Risk Management DEBRIS REMOVAL OCTOBER 2017/MARCH 2018 Scope of work Reconnaissance divers, side scan sonar Removal of debris, focus on hazardous items Collection of benthic samples Risk communication Partnership with local First Nations (assistance with field work, waste disposal) 17

18 Case Study - Risk Management DEBRIS REMOVAL - RECONNAISSANCE Divers observed a wide variety of debris during reconnaissance and coverage was extensive Domestic debris dominant around first finger (cans, plastics, bicycles etc) Fishing debris (nets, traps, boat parts) was dominant around second and third finger Several batteries observed Eel grass beds observed closer to foreshore Removal focused on hazardous items (batteries) Cleared five larger areas (10 x 10 m) to monitor recovery of benthic community 18

19 Case Study Risk Management DEBRIS REMOVAL Based on sidescan sonar results and diver observations, waterlot was classified into areas of high, moderate, and low magnitude of debris presence low moderate high 19

20 Case Study Risk Management DEBRIS REMOVAL With the assistance of the local First Nation, Golder and DFO removed a total of 18 m 3 of debris from the SCH waterlot including: 30 lead-based batteries A portable generator Outboard motor Oil canisters and a fuel pump 15 abandoned crab and prawn traps Benthic community samples were collected from five cleared areas at the SCH and two reference areas. These stations be resampled in one year to monitor recovery 20

21 Case Study Risk Management RISK COMMUNICATION Golder, Fisheries and Oceans Canada, and members of community met in March 2018 to discuss strategies for risk management of the SCH, specifically reducing the input of debris and improving stewardship of the waterlot Some strategies that will be explored include: Educational campaigns directed toward local school Use of underwater video footage as an educational prop Involvement of school groups in the next round of benthic sampling children can learn about the local biology and develop an interest in maintaining a healthy aquatic ecosystem Ongoing work with Fisheries and Oceans to establish a local harbour authority 21

22 Establishing a Harbour Authority HARBOUR AUTHORITIES The creation of Harbour Authorities helps the Small Craft Harbour program to: provide essential services to harbour users keep essential harbour facilities in good repair establish and enforce rules, and represent the needs of users at the community level. Currently the SCH does not have a Harbour Authority established. DFO and the community are working together to establish a Harbour Authority to manage the SCH. 22

23 Establishing a Harbour Authority DFO and the community are working together to establish not only the education plan for site users outlined earlier but also to become the Authority and Harbour Manager for the site. To make this happen, the community is working to develop a business plan, Establish site-use rules that will meet the needs of the community and also ensure a safe and clean harbour. SCH is providing support to the First Nation to participate in the abandoned and wrecked vessels removal program, clean harbour initiatives and other required management activities. 23

24 To Summarize RISK MANAGEMENT CASE STUDY The environmental liability established at the site was the trigger for further work to assess and clean up the Harbour. Upon further assessment it was decided that the scope of this work extends beyond simple remediation of site debris. Establishing a local harbour authority and educating site users is essential to the ongoing site clean-up activities and to ensuring the site is not re-contaminated in the future. 24

25 Thank you. 25