When Chieftain Metals began operating a water treatment plant at its Tulsequah Chief site some observers thought that the acid mine drainage problem was solved, while others noted concerns about the company’s finances and ability to operate the plant effectively. Unfortunately those concerns have been realized.
The Tulsequah Chief mine was operated by Cominco in the 1950’s. The mine site is on the Tulsequah River, the main tributary to the Taku River, upriver of prime salmon spawning and rearing habitat, including Flannigan Slough. When metal prices dropped Cominco abandoned the site without undertaking any decommissioning or pollution control. As the current owner of the Tulsequah Chief site, Chieftain is responsible for remediating the historic acid mine drainage. A series of cleanup orders from the British Columbia and Canadian governments, as well as government permits, require that the pollution be halted.
In June 6, 2012, letter Chieftain notified Environment Canada of its “intention to curtail activities” at the water treatment plant and “enter into a period of non-compliance with the conditions of Waste Water Discharge Permit #105719.” Chieftain noted that “plant operation has not met expectations” and listed engineering problems, including larger amounts of toxic sludge than expected and challenges in disposing it. Chieftain also noted that operating costs were projected to be approximately $1 million/yr, but actually were on a pace to be over $4 million/yr. As a result acid mine drainage, and its associated toxic heavy metals, is probably once again flowing into the Tulsequah River. Previous inspections have found the discharge to be acutely lethal to fish and other aquatic organisms.
Chieftain’s June 6 letter to Environment Canada says the water treatment plant will not resume full operation until the technical problems are fixed and the company is able to obtain financing for mine development. No timeline for this has been provided. Given the financial difficulties faced by previous owner Redfern, and now Chieftain, it is certainly conceivable that Chieftain will not be able to obtain additional financing.
Chieftain, and even Environment Canada, has suggested that the only way to permanently halt the pollution is to develop the mine. While re-developing an abandoned, previously operating mine to address historic pollution problems caused by inadequate decommissioning of the site might be the most economically attractive approach for the company and the Province, relying on mining as a remediation strategy has significant risks.
In reviewing the current Tulsequah Chief mining situation I see two major issues with operating for closure: (1) where to safely store a large quantity of potentially acid producing waste in perpetuity; and, (2) how to provide access to the mine – both a road and river-barge access are problematic in terms of their impacts.
From an engineering perspective, an operating mine is not necessary to halt the acid mine drainage. In fact, in 1992 Redfern and SRK Consulting developed a plan for mine remediation that could be implemented without an operating mine, but regulatory agencies allowed the company to delay implementation in hopes of re-opening the mine.
Operating for closure is an attempt to compensate for previous poor management decisions. Such a strategy may create new problems equal to or worse than the original problem and does not guarantee that future management decisions will be exempt from management errors.
Starting up a new mine at the Tulsequah Chief site is not necessary to address the historic acid mine drainage problems. Given the economic and access challenges facing the Tulsequah Chief proposal a new mine may never happen. For 20 years now the Province has been looking for an operator to mine for closure, and for most of this time pollution from the mine has been impacting the river. It’s probably time to make some tough, but realistic, decisions to look at remediation strategies that are not dependent on an operating mine.
• Dr. Chambers is the president of the Center for Science in Public Participation, a non-profit corporation formed to provide technical assistance on mining and water quality to public interest groups and tribal governments. He has 15 years of technical and management experience in the mineral exploration industry, and for the past 20 years he has served as an advisor on the environmental effects of mining projects both nationally and internationally.