May 2006

Creating a new economy through closure

Sullivan Mine closure sets the barrier for sustainable practices

By H. Ednie

After 92 years of production, Teck Cominco’s Sullivan Mine closed on December 21, 2001. Throughout its lifetime, the mine produced over $20 billion in lead, zinc, and silver metal and was home and heart to over four generations of miners and their community in Kimberley, British Columbia.

Sullivan was an underground mine with a complex orebody, composed primarily of sulphide and iron sulphides.

The nature of the mine lends itself to acid rock drainage (ARD) and subsequent challenges including metal leaching into surrounding waters. The long history of the mine, extending far beyond the early days of environmental management such as we recognize today, left legacy issues to be addressed. And the local town of Kimberley, founded in the 1930s as a company town, was faced with a real challenge to remain sustainable after mine closure.

Teck Cominco has earned international recognition for its proactive reclamation and mine closure work—both on the environmental side and in helping the community rebrand itself. In fact, the company hosted, along with the City of Kimberley and the World Bank, the Sullivan Round Table, an international gathering of experts and representatives of communities of interest to examine the social, environmental, and economic legacy of the Sullivan and other mine projects. The aim was to set the stage for the development of best practices in sustainability.

Reclamation of Sullivan

The earliest programs to address environmental concerns at the Sullivan Mine began in the 1960s, targeting waste discharge to watercourses and the reclamation of waste disposal areas on land. Research into revegetation and soil cover technology to turn disturbed land into productive sites began in 1972.

By the mid-1970s, the tailings disposal facilities were upgraded and a drainage and effluent collection and treatment system was under design and construction. The company pioneered the development of high-density sludge water treatment and installed the first operating plant in the world to treat acidic drainage water. By late that decade, the plant was commissioned, arresting the flow of contaminated mine drainage to Mark Creek and tailings effluent to the Cow and James creeks.

By the early 1990s, recognition of the finite life of the mine culminated in the development of a reclamation and closure plan. The company ran vegetation test plots, and worked to prevent negative impact from the tailings and waste sites. In 1991, closure plans were submitted for public review, and the Sullivan Mine Public Liaison Committee was formed. The closure plan addressed the principal concerns including acid rock drainage, protection of watercourses, reclamation of land, and protection of the public from potential safety hazards.

By 1995, the BC Ministry of Energy, Mines, and Petroleum Resources issued a reclamation amendment permit to the mine. However, two years later, the BC Ministry of Environment issued its Contaminated Site Regulations, and the Sullivan Mine had two ministries to work with in the closure and decommissioning of the site.

“The Ministry of Environment’s process was much more directive,” said Bruce Dawson,Teck Cominco who stayed on to oversee reclamation work after a longtime employment at the mine.“It involved multiple stages of investigation, submission and approval of plans, and public review requirements.”

Ultimately, the province became aware there were two ministries vying over one process, and the decision was made that the first ministry on the case took priority over ‘core’ mining activities. However, the Sullivan team had pre-done their work, on ground water, soil contamination, and metal uptake in vegetation, so were in a good position to undertake the collection of information the Ministry of Environment wanted. So, information was available to meet the new Contaminated Site Regulations.

“We met the requirements of both ministries concurrently,” explained Dawson. “For the Ministry of Mines,we’ll place the final engineered soil cover this year and will have met their requirements. For the Ministry of Environment,we can’t meet the soil standards. The Kimberley area soil doesn’t meet them due to the presence of natural mineralization, and the mine wastes exceed the standards. Instead, riskbased standards were used to meet the Ministry of Environment Remediation requirements.”

The ecological risks associated with the retired mine require both aquatic and terrestrial assessments.The aquatic assessment included surface and groundwater sampling, algae and plant collection, fish tissue sampling, insect collection, and food chain observation.

Page 1 of 3. Next
Post a comment

Comments

PDF Version