Presentation on theme: "Britannia Mine Remediation Project Britannia Shoreline Public Meeting June 25, 2008 Britannia Shoreline Public Meeting June 25, 2008 www.britanniamine.ca."— Presentation transcript:
Britannia Mine Remediation Project Britannia Shoreline Public Meeting June 25, 2008 Britannia Shoreline Public Meeting June 25, 2008 www.britanniamine.ca
Why are we here? Provide a brief overview of where we are at Engage members of the community about where we are going. –Build on significant stakeholder consultation which contributed to the Overall Remediation Plan
Why are we here? Focus is on the Britannia shoreline and eventually setting resource conservation objectives (RCO).
Agenda Welcome and Introductions Overview of the Britannia Remediation Project Summary of Environmental Monitoring Resource Conservation Objectives Participation and Feedback Closing: Questions and Answers
What’s the Problem? Britannia Mine - “the largest point source of metal pollution in North America discharging to a marine environment” until October 2005 Naturally occurring metal sulphide orebody
Environmental Issues Acid Rock Drainage (ARD) was discharging from the mine (~5million m 3 /year) - copper, zinc, cadmium, pH~3.5 Metal-contaminated groundwater: –Alluvial Fan of Britannia Creek –Waste dump leaching Metal-contaminated surface water (run-off) All the above impact aquatic life in Howe Sound and local waterways: –Squamish River salmon run
Britannia Creek Alluvial Fan (‘Fan Area’) Britannia Creek Mill Building 4100 Level Mine Entrance ‘Concentrate Wharf’ BC Museum of Mining Highway 99
4100 L 2700L 4100 Portal 4100 Plug Mineral Creek Britannia Creek Howe Sound Britannia Beach #10 Shaft Victoria Shaft 3D Cutaway of Britannia Mine 2200 Portal 2700 Portal Jane Basin Mine Levels defined in feet measured downwards from highest elevation in mine
Howe Sound Assessment of contaminated sediments (Environment Canada) Treatment: of mine drainage Management of contaminated groundwater Collection: (Plug installed in 2200 level In 2001 by UBC/CERM3) Mill Management of contaminated waste rock and groundwater Province’s Remedial Concept Prevention: Inflow diversion Use of mine void as storage/ balancing reservoir New Deep Outfall Plug with control valve Inflow Diversions Collection/storage of ARD Treatment of ARD Deep outfall Groundwater capture/treatment Surface water management Contaminated soil management Monitoring & Risk Assessment
Overall Remediation Plan (ORP) Prepared by Golder on behalf of Ministry of Agriculture and Land (MAL) in 2003; Input from Crown Land Restoration Branch, technical consultants, BC and Federal regulators and project stakeholders; Strategy evolved from years of study and assessment since mine closure in 1974
ORP Objectives 1.Reduce discharge of harmful substances (metals) to habitable areas and aquatic communities; 2.Protect, sustain and promote recovery; 3.Achieve and maintain acceptable levels of risk to health and safety for humans and other terrestrial organisms; 4.Implement in a timely and cost effective manner
Review of Progress 1.Immediate Actions 2200 Plug Removal of Mill Building Concentrate Pile Removal of lower settling pond sediment Removal and stabilisation of sedimentation pond Removal of mill slope soils* Ground and storm water interception in Fan Area Surface water diversions in Jane Basin First stage of monitoring and assessment *Now a potential action: surface & groundwater control in lieu
Review of Progress 2.Committed Actions Mine water collection and storage Mine water treatment plant New deep water outfall WTP sludge disposal Stage 2 of monitoring and assessment
Review of Progress 3.Potential Actions Additional Fan Area groundwater interception Additional surface water diversions Remediate additional mine wastes and portals* Additional Fan Area surface and storm water management, collection and treatment** ? Remediate Fan Area soils*** ? Remediate Fan Area inter-tidal zone*** *Some completed/in progress. Review ongoing ** Underway *** Contingent on risk assessment findings
Additional ORP Requirements Environmental remediation is primary focus of the ORP, however additional objectives include: –Mitigation of public health and safety risks –Compliance with Section 10.6 and 10.7 of the BC mine Code
ORP Status Summary Immediate remedial actions have all been implemented (excl. Mill Slopes) Committed remedial actions have all been implemented Potential remedial actions –Most implemented –Remainder under review
ORP Status Summary ‘Potential’ remedial actions ongoing/under consideration –2200 Level Waste Dump Hazardous Waste identified and remedial plan in progress to be implemented this year –2200 Level Waste Dump drainage improvements – to be implemented this year –Beta Portal discharge diversion (potential diversion back into the mine)
Risk Assessment Screening-level risk assessment was used to identify environmental risk and prepare ORP A more detailed aquatic and terrestrial monitoring programme and risk assessment was proposed (Tier 2 Assessment)* The detailed assessment would be used to refine potential risks and select any appropriate additional remedial actions Current status: defining Resource Conservation Objectives
Planning out risk assessment?Planning out risk assessment? –Large site –Mine workings that exist across 2 watersheds Planning out risk assessment?Planning out risk assessment? –Large site –Mine workings that exist across 2 watersheds
Why a Risk Assessment Plan?Why a Risk Assessment Plan? –Large site –Mine workings that exist across 2 watersheds –Ore processing area located along Howe Sound
Furry Creek Watershed Limited surface water sampling Water chemistry generally good. Limited remedial work Recommended that a Problem Formulation/Sampling & Analysis Plan be prepared (first part of a risk assessment)
Britannia Creek Watershed Dominant influence on Britannia Cr water quality is from Jane Creek Some waste materials removed; planning underway to remove Haz Waste at 2200 level. Jane Creek drains a naturally mineralized area.
Britannia Creek Watershed
RA not likely to contribute to near-term remedial actions Natural mineralization of the area may constrain practicability of remediation to plausible RA endpoints Near-term: –Investigate sources –Remediation of selected potential sources
Fan Area Monitoring indicates: –Contaminant concentrations in nearshore groundwater are high –Biological assessment and testing – significant adverse localized effects Risk assessment at present is not seen to play a major role until sources are controlled Development of Resource Conservation Objectives will aid in defining remedial endpoints at this time and will form a basis for future RA. –How clean is clean enough?
Environmental Monitoring Findings Britannia Shoreline 3 main program components: –Marine water quality –Nearshore groundwater quality (porewater) –Shoreline ecology
Marine Surface Water Chemistry - Intertidal
Marine Surface Water - Subtidal Total copper Dissolved copper 0.002 mg/L = chronic WQG 0.003 mg/L = maximum WQG
Pore Water Chemistry 0.002 mg/L = chronic WQG 0.003 mg/L = maximum WQG
Pore Water Toxicity- Mytilus galloprovincialis 2005 2006 (ns)
Caged Bivalve Study - 2005 Change in Weight (g; mean SD) Tissue Copper (mg/kg ww)
Resource Conservation Objectives How good is good enough? –More often thought of in terms of chemical concentrations –Can also be expressed in ecological terms as a shoreline community condition and/or function
Resource Conservation Objectives How good is good enough? –Example: percent cover by mussels and barnacles Community interests and values assist scientists in defining what is “good enough”
Resource Conservation Objectives Shoreline Use: –Human use of the shoreline –Ecological use of the shoreline –What is important to you? Community aspirations should influence resource conservation objectives and remedial measures to attain those
Resource Conservation Objectives In addition to community values, there are regulatory requirements. –Ministry of Environment, Environment Canada, Fisheries and Oceans Canada Agency consultation will take place, following community consultation (projected for Fall 2008) Agency input to the project has been ongoing through the TAC –Agency representatives in attendance tonight.
Now its your turn… Questionnaire available here and online: –http://websurvey.golder.com/wsb.dll/lnikl/BritanniaShorelineConsultation.htmhttp://websurvey.golder.com/wsb.dll/lnikl/BritanniaShorelineConsultation.htm Scientists and engineers working on the project are present this evening to help you Please review the posters and other materials, ask them questions, formulate your thoughts and tell us what you think!