Tulsequah Mine Information

The Tulsequah Chief mine, located 100 km south-west of Atlin B.C., is a historic copper/lead/zinc, silver and gold producer which operated from 1950 to 1957. The mine site is on the Tulsequah River about 10 km upstream from its confluence with the Taku River which drains into Taku Inlet near Juneau, Alaska.


In 1997, Redfern Resources Ltd. applied to the Province for an Environmental Assessment (EA) Certificate to develop a 2,250-tonne-per-day underground copper, lead, zinc, gold and silver mine at the old mine site. It conducted various development activities until winding down in 2008 and being placed in receivership in 2009.

The mine is currently owned by Chieftain Metals (Chieftain), who acquired the property in 2010 and received an EA certificate in 2012. Chieftain agreed to address historic acid rock drainage issues as part of re-development of the mine.

In 2012, Chieftan Metals obtained a Mines Act (MA) permit for limited construction works associated with the first phase of mine re-development. As part of the coordinated permitting, an Environmental Management Act (EMA) permit for effluent discharge associated with construction of the mine was also issued. The intent was that water impacted from early construction activities, as well as a portion of water from the historic underground workings would be collected and treated. However the construction of the mine was suspended and the site was placed in a care and maintenance status. On September 6, 2016 Chieftain Metals was placed into receivership.

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 Metals operated a temporary acid-water treatment plant, untreated acid mine drainage has been discharging into the 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. The acid drainage is created when naturally occurring sulphide minerals in the mined rock and waste rock are exposed to air and water. This process can go on for many years, creating potentially serious environmental issues.

In October 2016, the Alaska Department of Fish and Game released a report on Tulsequah Chief Acid Mine Drainage and Dolly Varden Char Whole Body Metals Concentrations that showed no significant difference in metal concentration in fish captured near the mine site compared to fish captured upstream and downstream.

Key Inter-Ministry Actions

Government implemented the Tulsequah Chief working group in September 2016 to bring together all provincial regulating agencies to ensure communication and coordination of action.

Shortly after Chieftain Metals was placed under receivership, on September 26, 2016, inspectors from the Ministry of Energy and Mines, the Ministry of Environment and a member of the Taku River Tlingit, inspected the Tulsequah Chief mine site. Inspectors found a number of non-compliance issues at the site including no caretaker on site, drainage and maintenance issues at the sediment pond, and the unsecured storage of chemicals. On September 26, 2016, the Ministry of Energy and Mines Deputy Chief Inspector of Mines issued orders under the Mines Act to address the deficiencies described in the inspection report.

The Ministry of Energy and Mines hired a contractor to properly secure all chemicals identified on site. This work was completed at the beginning of December 2016. Due to winter and freezing conditions at the mine, the plan to address drainage and maintenance aspects of the sediment pond has been scheduled for summer 2017.

Aquatic & Ecological Risk Assessment

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. However, in summer 2016, in response to concerns about the risk assessment findings, the Ministry of Environment instructed the company to complete another Aquatic Ecological Risk Assessment. Chieftain Metals did not complete this second assessment prior to the court-ordered receivership. In response, the B.C. Ministry of Environment has undertaken to complete the Aquatic Ecological Risk Assessment; all the field work was completed in 2016 and the final report has now been released – see link to the report below. The findings from the study have established whether and to what extent mine effluent may be impacting the environment and provided recommendations for next steps.

Compliance & Enforcement

As neither Chieftain Metals nor its Receiver has complied with the Deputy Chief Inspector of Mine’s orders issued on September 28, 2016, the Chief Inspector of Mines escalated enforcement action on July 4, 2017 by issuing orders under Section 35 of the Mines Act.  The orders require the Company and/or its Receiver to immediately prepare and submit a plan to re-establish compliance in relation to the issues identified in the previous inspection report - see link below.  Remedial action plans are required to be submitted to the Chief Inspector of Mines by July 31, 2017. If the orders are not complied with, further escalation of enforcement actions will be considered. 

Chieftain Metals’ primary secured creditor has advised the Ministry of Energy and Mines that it intends to retain an environmental consultant to review existing data and develop a set of remediation concepts for the mine by the end of September 2017. Should the remediation plan be unduly delayed or not meet Ministry requirement, the Ministry of Energy and Mines will take further action and may initiate the development of a remediation and closure plan for the site. 

Reports & data

Ministry of Energy, Mines and Petroleum Resources (MEMPR)*

*Previously (MEM)

Ministry of Environment and Climate Change Strategy (ENV)

Environmental Assessment Office

State of Alaska Reports