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Lessons Learned in Remediafing Legacy Uranium Mine and Mill

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Lessons Learned in Remediafing Legacy Uranium Mine and Mill Lessons Learned in Remediang Legacy Uranium Mine and Mill Sites in Northern Saskatchewan Dianne E. Allen P.Eng., PMP David Sanscarer, Ph.D., P.Eng. and Ian Wilson, AAg Saskatchewan Research Council, SK, Canada 2015 RPIC Federal Contaminated Sites Regional Workshop Edmonton, AB, June 4, 2015 1 Copyright © SRC 2015 Project CLEANS CLeanup of Abandoned Northern Sites Ê Saskatchewan Research Council was contracted by the Government of Saskatchewan in 2006 to manage the remediaon of abandoned uranium sites in northern Saskatchewan Two legacy mill sites with unconsolidated tailings • Gunnar mine and mill (1955 – 1963) • Lorado mill (1957 – 1960) Ê Thirty-five legacy uranium mine sites • SRC has iniated remediaon at 19 of these 2 Copyright © SRC 2015 3 Copyright © SRC 2015 Gunnar Mine and Mill Before Building Demolion in 2011 4 Copyright © SRC 2015 Environmental Legacy and Hazards at Gunnar Ê No decommissioning when closed in 1964 Ê Uranium tailings were deposited in three areas – Mudford Lake; - Gunnar Central – Langley Bay (a part of Lake Athabasca) Ê Buildings standing unl SRC demolished in 2011 Ê Industrial waste products; asbestos products Ê Flooded open pit and underground workings Ê Large amount of waste rock mixed with debris Ê Radioacve loading into Lake Athabasca 5 Copyright © SRC 2015 Lorado Mill Site Before Remediaon Began in 2014 6 Copyright © SRC 2015 Environmental Legacy and Hazards at Lorado ÊGamma radiaon from tailings is above background ÊAcidic runoff over tailings into Nero Lake ÊAluminum precipitate in downstream Beaverlodge Lake ÊParal decommissioning and burial of buildings in 1990 le sink holes and debris ÊIndustrial debris dumps including hazardous materials 7 Copyright © SRC 2015 Public Safety Hazards at Abandoned Mines Adits, portals Raises, shas, breakthroughs Mine workings, crown pillars 8 Copyright © SRC 2015 Public Safety and Environmental Hazards at Abandoned Mines 9 Copyright © SRC 2015 SRC Managing Remediaon Acvies Ê Environmental assessments, including EIS Ê Community engagement Ê Gamma radiaon surveys Ê Asbestos abatement and building demolion Ê Tailings cover design and construcon Ê Water treatment Ê Closure of mine openings; re-contouring waste rock piles Ê Removal of hazardous materials to licensed facilies Ê Burial of non-hazardous materials Ê Environmental monitoring 10 Copyright © SRC 2015 Challenges at Remote Legacy Sites Ê Legacy mines with limited historical & mine engineering informaon Ê Short field season in northern Saskatchewan Ê Remote and no road access Ê High expectaons for regional economic benefit Ê Mulple levels of government funding: NRCan and SK MECON Ê Mulple levels of regulatory oversight: CNSC, EC, DFO, SK MOE Ê Community cynicism due to decades long neglect of these legacy sites 11 Copyright © SRC 2015 SRC Learned How to Meet the Challenges at Remote Legacy Sites Ê Lack of informaon requires: – Assessments and adapve management Ê Complex logiscs requires: – Careful planning – Maximizing use of regional resources, e.g., equipment – Minimizing waste, e.g., sludge from water treatment Ê Community concerns requires: – Commitment to community engagement 12 Copyright © SRC 2015 Aboriginal and Community Engagement Ê We did: – Start early in planning stage – Use local knowledge of site condion – Capacity building before work began (e.g., construcon safety and asbestos abatement) – Hire local personnel – Use local ideas to solve technical and communicaon challenges Ê We learned: – Regional economic benefit takes foresight and commitment Ê We are doing more: – Consulng local businesses and residents for cost-effecve logiscs planning – Facilitang employment readiness (e.g., drivers licenses) – Managing expectaons regarding melines to site closures 13 Copyright © SRC 2015 Regulatory Engagement Ê Being publically funded and managed environmental cleanups regulators have a high interest and buy-in Ê We did: – Regulatory workshops at early planning stage (e.g., seng objecves) – Open communicaon with regulators Ê We learned: – Regulatory relaonships need careful management Ê We are doing more: – Managing expectaons regarding melines and closure criteria – Remembering regulators’ role • “Proponents propose; regulators dispose.” 14 Copyright © SRC 2015 Site Assessments Ê We did: – extensive environmental assessments – gather tradional and local knowledge – engage experienced environmental consultants Ê We learned: – Legacy sites are oen more complex than is readily visible Ê We are doing more: – Phase 1 and 2 assessments for even seemingly simple sites to reduce uncertainty and underesmaon of hazards 15 Copyright © SRC 2015 Innovave Site Assessment Method: Unoccupied Aerial Vehicles (UAV) Rix Athabasca – Smiy Mine • We learned: UAV offers affordable imagery to reveal site aspects 16 Copyright © SRC 2015 During mining (1950s) UAV Point Cloud Data Capture Aer remediaon (2013) Demonstrang Success at the Cayzor Mine 17 Copyright © SRC 2015 Seng Remediaon Objecves Ê We did: – Aboriginal, community and regulatory involvement to: • Set clear objecves • Get buy-in from all pares early in planning process Ê We learned: – referring to objecves prevents or limits scope expansion Ê We are doing more: – Modifying objecves as budget changes – Risk assessments to guide objecve seng 18 Copyright © SRC 2015 Resource Planning Ê We did: – Hire appropriate experse for project management – Select consultants for technical experse and experience – Develop understanding of regional capacity for service delivery Ê We learned: – Legacy sites require specialized and general remediaon experse – Regional resources are limited – Remoteness limits small contractors’ ability to bid Ê We are doing more: – Employment readiness, e.g., environmental monitoring – Planning coordinated projects to reduce mobilizaon costs – Larger contracts to aract regional contractors 19 Copyright © SRC 2015 Risk Assessment and Management Ê We did: – Detailed human health and ecological risk assessments – Community consultaon on: • Site use and future use • Seng priories for sequencing site remediaons Ê We learned: – Remediaon costs of remote legacy sites difficult to esmate – Remote sites that are rarely accessed present less risk to people, e.g., radiaon levels Ê We will do more: – Assessment of hazards associated with underground mine workings – Balancing expenditures for site closure vs. risks to public 20 Copyright © SRC 2015 Assessment of Underground Mine Hazards 21 Copyright © SRC 2015 Innovave Closure Method: Stainless Steel Covers on Mine Openings See: Sanscarer et al., Stainless Steel Covers – An alternave closure method for remote mines. Mine Closure 2015 Conference, Vancouver, June 1-3, 2015 22 Copyright © SRC 2015 Procurement of Services Ê We did: – Incorporate regional aspiraons into criteria in request for proposals – Set regional content targets, bonuses and penales in contract – Keep communies informed of project opportunies Ê We learned: – Sustainability objecves increase support for project – Sustainability targets take commitment and are achievable Ê We are doing more: – early discussions with regional contractors and suppliers 23 Copyright © SRC 2015 PBN Nuna/Milestone Joint Venture Manpower Demographics: 2014 32% 54% 5% 9% Athabasca Basin - Aboriginal Athabasca Basin - Non-Aboriginal Other - Aboriginal Other - Non-Aboriginal Courtesy of PBN Nuna / Milestone Joint Venture 24 Copyright © SRC 2015 PBN Nuna/Milestone Joint Venture Equipment Hours in 2014 35% 65% Athabasca Basin Equipment PNM Equipment 25 Copyright © SRC 2015 Courtesy of PBN Nuna / Milestone Joint Venture Saskatchewan’s Project CLEANS is an example of connuous improvement to meet the challenges of remediang legacy uranium mine and mill sites in northern and remote areas of Canada. 26 Copyright © SRC 2015 Copyright © SRC 2015 .
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