Clinton Creek is an abandoned asbestos mine located 100 km northwest of Dawson City, Yukon and is currently managed by the Yukon Government. The open pit mine was open from 1967 to 1987 when the economically valuable asbestos was mined. 16M tones of serpentine rock and 940,000 tones of chrysotile asbestos were removed. While an abandonment plan was attempted, the local creek channels, waste rock and tailings piles destabilized, causing substantial erosion and flooding. Since 2003, the Government of Yukon has managed the remediation plan with the focus to maintain the environmental integrity of the site and ensure there are no adverse effects to human health and safety. Wood was commissioned to carry out field investigations at the site in support of determining mine close options as part of the Clinton Creek remediation design. The 2017 and 2018 field programs included geotechnical assessment of waste rock and tailings areas to evaluate stability. As part of this program, a team of occupational hygienists and safety specialists was assembled to prepare a detailed asbestos exposure safe work procedure and conduct a worker exposure evaluation for asbestos. The process of evaluating potential hazards to workers exposed to naturally occurring asbestos (NOA), the development of safe work practices, completion of a worker exposure assessment and the refinement of the safe work procedures based on the exposure assessment will be presented.

The Government of Yukon had very limited data on potential worker and site occupant exposures that may affect site management, construction and rehabilitation and local inhabitants. The asbestos exposure monitoring program was developed initially by determining the potential exposure scenarios and refining them based on field observations. Ambient air samples were initial collected prior to disturbance activities. The ambient samples were collected inside vehicle cabs, downwind on work and in the mobile decontamination unit among other locations. Daily occupational samples were collected based on the disturbance activity. Samples were collected in general accordance with The National Institute for Occupational Safety and Health (NIOSH) Method 7400 and analysed on-site with select samples analysed by NIOSH Method 7402. The project occupational exposure limits were adjusted for a 12-hour workday.

Based on the worker exposure assessment, it was determined that practical safe work procedures were effective in reducing the airborne asbestos fibre concentrations below the regulatory standards in the Yukon as well as more stringent international standards set for the project (American Conference of Governmental Industrial Hygienists). Based on scientific results, the team confirmed the overly conservative and costly safe work procedures used in the initial field program could be reduced. While base-level personal protective equipment was still required, work procedures (i.e., dust suppression, equipment and worker decontamination and worker rest procedures) were able to be effectively reduced while ensuring a high level of worker protection which lowered project costs and improved on-site productivity. This is a clear, practical project showing practitioners how to evaluate and confirm hazards and adjust on-site protocols accordingly. Aspects of this project can be used for any construction related project where NOA or other natural occurring worker hazards may be a concern.

Patrick Campbell, Senior Associate Environmental Scientist and Manager, Health, Safety, and Environment Group, Wood
Patrick Campbell is a Senior Associate Environmental Scientist and Manager of the Health, Safety, and Environment group in Winnipeg, Manitoba. Patrick has over 20 years of experience in assessing and managing occupational health and safety and environmental issues across Canada. He is a Canadian Certified Environmental Practitioner (EP) and a Canadian Registered Safety Professional (CRSP). Patrick is a Key Speciality Leader in Wood’s Environmental Remediation Service Line. Patrick is well versed the assessment and management of contaminated properties to meet regulatory, legal and site management requirements. As a senior client manager and technical lead, Patrick has managed numerous contracts for Public Services and Procurement Canada, Indigenous Services Canada, Defence Construction Canada/Department of National Defence, Canadian Nuclear Laboratories and other local, provincial and federal agencies. Through practical experience or as a member of an applied research team, Patrick evaluates cost effective and reliable methods of assessment, remediation and risk management of contaminated sites. Patrick has won a number of provincial and a national engineering award for innovative and sustainable measures for environmental remediation and emergency response including the Association of Consulting Engineering Companies’ Tree for Life award. Patrick routinely assists owners, managers and contractors in meeting their environmental obligations through education and consulting services.

Over the last 12 years, Crown-Indigenous Relations and Northern Affairs Canada (CIRNAC) has been conducting environment, health and safety (EHS) compliance audits of their Northern Contaminated Sites Program (NCSP) and projects as part of their EHS Management System (MS). CIRNAC’s portfolio of contaminated sites include abandoned military, oil and gas, and mine sites located throughout Canada’s North and many are located in remote areas. These remote sites pose unique health and safety hazards and environmental aspects since assessment, remediation and monitoring of these sites require remote travel and work; possible interaction with wildlife; as well as regulatory requirements which span multiple jurisdictions. Each year, CIRNAC selects candidate sites to be representative of the varying scope; stage of assessment, remediation or monitoring; contaminant type; and, regional location of the sites within their portfolio. With increasing practice, CIRNAC has modified auditing scope and methods to ensure that the audit objectives are met despite the unique conditions of remote sites. Modifications have included: adjusting for minimal on-site time through off-site interviews; pre-audit document requests; and, prioritizing audit areas to ensure that higher risk areas are covered. This presentation discusses findings from the audit program over multiple years and will demonstrate how CIRNAC has taken these findings and implemented changes to their programs and policies to reduce health and safety risks and potential impact to the environment at their projects sites. Some areas of findings from past audits include: air emissions; fuel and hazardous materials management; wildlife management; remote site access; vehicle safety; safe occupation of workplace; and, safety awareness and training. Sharing these findings and outcomes of the program may help other custodial departments improve the implementation of their own compliance audit program.

Amy Elder, Analyst, Northern Contaminated Sites Program Branch, Crown-Indigenous Relations and Northern Affairs Canada
Amy Elder is an Analyst with Crown-Indigenous Relations and Northern Affairs Canada (CIRNAC) for the Northern Contaminated Sites Program (NCSP) Branch in Gatineau, Quebec. Amy is project manager for the Environment, Health and Safety Compliance Audits for the NCSP and is a Headquarters representative on the CIRNAC NCSP Environment, Health and Safety Working Group.

The Saskatchewan Research Council (SRC) is managing the remediation of 37 legacy mines (Project CLEANS [Cleanup of Abandoned Mines in Northern Saskatchewan]) on public land in northern Saskatchewan on behalf of the Saskatchewan Ministry of the Economy. Canada's first recorded discovery of uranium came in the 1930's when pitchblende, a major uranium bearing mineral, was discovered in the Northwest Territories. The quest for uranium soon led to an exploration boom that resulted in the operation of several mines in the Uranium City area of Saskatchewan. Many of the operating mines established in the 1950-60’s became abandoned once the demand for uranium subsided. These abandoned remote legacy mines now pose potential health and safety risks for the public. Site hazards include openings to the underground mine workings and potentially unstable crown pillars (defined as a rock mass situated above an uppermost stope of the mine). Evaluation of the long-term surface stability of crown pillars overlying the underground mines is an important component of mine closures.

In Saskatchewan, regulatory requirements are in place to address the openings to underground workings and for proper closure and/or monitoring for long-term public safety. However, there are no guidelines for the mitigation of potentially unstable crown pillars. As more legacy mining sites in Canada are reclaimed, similar situations may be encountered in other jurisdictions. With these challenges in mind, Project CLEANS has continued to search and implement mitigation efforts to reduce these risks. The approach selected must also examine the historical mining methods and practice and the effect of time on crown pillar stability. This presentation will review the challenges encountered on Project CLEANS sites and share the steps completed and lessons learned by SRC to forge the path-forward for mitigation of these risks. Through recent remediation applications and case examples from current remote legacy sites, SRC’s approach for crown pillar remediation is presented.

Patty Ogilvie-Evans, Senior Geologist, Saskatchewan Research Council
Patty Ogilvie-Evans is a Senior Geologist with the Saskatchewan Research Council (SRC) and is a part of SRC’s Environment Remediation team working with Project CLEANS (Cleanup of Abandoned Mines in Northern Saskatchewan). Patty has been a Geologist in Saskatchewan for the past 16 years and has a background in underground and open-pit mining and several years of uranium, gold and diamond exploration in Saskatchewan. Patty primarily works closely with the remediation projects to help determine and understand the underground workings on the abandoned legacy sites in Northern Saskatchewan and assists with the overall remediation of these sites as a technical lead. She has been instrumental in the development and progress of the alternative mine closure implemented on remote sites. She graduated from the University of Saskatchewan with a B.Sc. in Geological Science and holds a Professional Geoscientist designation in the province.