Tulsequah Mine Information

The Tulsequah Chief Mine (“the mine”) is a historic underground copper/lead/zinc mine which was operated by Cominco from 1951 to 1957. The mine is located on the Tulsequah River about 10 km upstream from its confluence with the Taku River, in the traditional territory of the Taku River Tlingit First Nation (TRTFN).

The Province remains committed to holding all past and present owners of the Tulsequah Chief Mine accountable to address clean-up of the site.

The Province is continuing to work closely with the Taku River Tlingit First Nation (TRTFN) as well as committed to engaging with stakeholders regarding a long-term approach to reclamation and closure that will include addressing acid rock drainage.

End of Receivership and Status of Chieftain Metals Inc.

  • West Face Capital Inc. is the primary secured creditor of Chieftain Metals Inc. (Chieftain). West Face Capital Inc. did not file materials in the Ontario Superior Court to seek to appoint a receiver by the court-mandated deadline of August 11, 2022. The Province’s position is that this concludes the receivership process. 
  • Chieftain, a company incorporated in Ontario, continues to retain its assets and interests. The process for the dissolution of Chieftain has been stayed by the Ontario Superior Court until after October 2022.

2022 Field Work

  • For the third consecutive summer field season, interim reclamation works continue at the Tulsequah Chief Mine in collaboration with the TRTFN and the Atlin Taku Economic Limited Partnership, the economic arm of the TRTFN.
  • Works occurring in the 2022 field season are consistent with previous years and include:
    • Continuing building and repairing stream crossings and bridges;
    • Airstrip erosion protection; and
    • Implementing year 3 of the 5-year water quality and aquatic effects program in the Tulsequah River, which will support and inform further reclamation plan development for the Tulsequah Chief Mine. 
  • For the second year, Teck Resources Limited has voluntarily provided funding for this work ($1.575M in 2021 and $1.685M in 2022).

Conceptual Closure and Reclamation Plan

In January 2019,  the Ministry of Energy, Mines and Petroleum Resources retained SNC-Lavalin and SRK Consulting to develop a conceptual Closure and Reclamation Plan for the Tulsequah Chief Mine Site.  Multiple technical workshops took place throughout 2019 to review remedial options.  Participants in the workshops included from the Taku River Tlingit First Nation, Teck Resources Limited and the Alaska Department of Natural Resources.

A final version of the conceptual Closure and Reclamation Plan was submitted to the Province in April 2020 – see link below.

The conceptual Closure and Reclamation Plan outlines a phased approach that involves a series of steps designed to reduce the ongoing contamination.  It is designed to be flexible, so changes can be made once more information is gathered from the site. Some of the first steps include repairing bridges, upgrading the access road, establishing an erosion protection berm and repairing the existing airstrip.


The mine is currently owned by Chieftain Metals Inc. (Chieftain) . Chieftain was issued a Mines Act mine permit to do limited construction works associated with the first phase of mine re-development. Chieftain undertook further exploratory drilling and feasibility assessments in anticipation of applying for full mine production approvals. An interim water treatment facility was established on site, but only operated for three months because of operational constraints. In 2015 activities at the mine site ceased, and the mine was shifted into care and maintenance status.  On September 6, 2016, Chieftain was placed into receivership.

In 2020, the BC Government (“the Province”) and the TRTFN participated in a hearing to discharge the receiver. In October 2020, the Ontario Superior Court approved the discharge of the receiver.  The primary secured creditor has until August 11, 2022 to apply to re-appoint a receiver in the proceedings.

Issues of Concern

The Tulsequah River is the primary receiving environment of mine effluent. Except for a short period of time in 2012, when Chieftain operated the interim water treatment facility, untreated acid mine drainage has been discharging into the Tulsequah River since at least 1957.

Acid mine drainage, also referred to as acid rock drainage, refers to the outflow of acidic water from metal or coal mines.

In 2014, Chieftain Metals Corp., at the request of the Ministry of Environment, undertook a comprehensive Aquatic Ecological Risk Assessment which found there had been no unacceptable risk to the Tulsequah River from their discharge during times of the year that are critical for salmon.

In 2016, an Aquatic and Ecological Risk Assessment was undertaken by SLR Consulting (Canada) Ltd.under contract to the B.C. Ministry of Environment and Climate Change Strategy.  The purpose of the 2016 AERA was to provide a current state assessment of potential impacts to aquatic receptors within the Tulsequah River, including the mainstem, braided channels and tributaries surrounding the Site. The report demonstrated metal concentrations pose unacceptable risks to fish, fish eggs and pelagic invertebrates in the zone immediately adjacent to the untreated/undiluted discharges from the mine but decreased in risk within 2km downstream of the mine site – see link below.

Compliance & Enforcement

Environmental Management Act:

On May 11, 2012, the Ministry of Environment (ENV) issued an Advisory for the accidental release of mine water. This was followed by a Warning issued for an unauthorized bypass of the water treatment plant on July 24, 2012, and subsequently a Notice of Non-Compliance for a sludge pond seep on December 6, 2012. Further advisories of non-compliance were issued on January 16, 2013 for not monitoring in accordance with the Discharge and Receiving Environment Authorization Amendment, and on October 15, 2015 for an unauthorized bypass of approved works.

Mines Act:

On September 26, 2016, the Ministry of Energy, Mines and Petroleum Resources’ Deputy Chief Inspector of Mines conducted an inspection at the site. On October 24, 2016, inspection orders were issued pursuant to section 15 (4.1) of the Mines Act for non-compliance with section 21 of the Mines Act and section 10.1.5 of the Health, Safety and Reclamation Code for Mines in British Columbia (the Code).

As Chieftain has not complied with the Deputy Chief Inspector of Mine’s orders issued on October 24, 2016, the Chief Inspector of Mines escalated enforcement action on July 4, 2017 by issuing orders under Section 35 of the Mines Act.  A further order was issued on October 27, 2017 further identifying non-compliance with part 10.7.20 of the Code. The orders required Chieftain to immediately prepare and submit a plan to re-establish compliance at the site. An adequate plan was not received by the set deadline.

In response, the Chief Inspector of Mines utilized their authority under section 17 of the Mines Act to cause work to be done to abate pollution to land and watercourses. The Ministry of Energy, Mines and Petroleum Resources issued a Request for Proposals for the development of a conceptual remediation and closure plan for the site in November 2018, resulting in the Tulsequah Chief Mine Conceptual Closure and Reclamation Plan  (April 2020) plan (link below).

The Ministry of Energy, Mines and Petroleum Resources issued a Notice of Escalating Enforcement Action to Chieftain in December 2018 that contains a detailed timeline of non-compliances under both the Environmental Management Act and the Mines Act – see link below.

Reports & data

Ministry of Energy, Mines and Low-Carbon Innovation (MEMLI)

*Previously (Ministry of Energy and Mines)

Ministry of Environment and Climate Change Strategy (ENV)

Environmental Assessment Office

State of Alaska Reports

B.C.-Alaska Water Monitoring Program