May 2006

Britannia Mine Reclamation

Showing the world how it’s done

By H. Ednie

Britannia water treatment plant

The Britannia Mine, located 50 kilometres north of Vancouver, British Columbia, was discovered in 1888 by A. A. Forbes, and by the 1920s, boom times were driving much activity on the site. Britannia was in its day the largest producer of copper in the British Empire. Until recently, it was also one of the biggest sources of metal pollution in North America. Operations continued until high costs and taxes caused mine closure in 1974. Since then, the abandoned mine has discharged acidic, metals-laden water from underground workings for copper ore and from tailings and waste dumps throughout the site. But a new future is in the works for Britannia.Through a unique partnership, the BC government is spearheading environmental site reclamation, while those involved with the “Britannia Project,” including the Mining Association of BC and the BC Museum of Mining and its sponsors are developing plans to make the Britannia site a world-class destination for education and recreation.


The mine workings run inland from the coast several kilometres, extending beneath open pits at the summit of an adjacent mountain, where copper, zinc, and cadmium in exposed massive sulphide orebodies leach into the mine.Until last fall, metals toxic to fish have flowed from the workings at up to one cubic metre per second, contaminating the creeks and shoreline ecology, and risking the aquatic life resources in Howe Sound.

“About 5 million cubic metres (5 billion litres) of contaminated water used to enter Howe Sound annually, bringing about 250,000 kilograms per year of contaminants into the Sound. The copper alone was the equivalent of dumping about 70 million pennies into the water,” said David Rector, general manager, BC operations, EPCOR.“The copper in the water is a significant issue, as it is highly toxic. In fact, sailors used to line the bottoms of their ships with copper, to prevent barnacles and other life forms from building up.”

Golder Associates has been project manager for the remedial efforts on behalf of the BC Ministry of Agriculture and Lands since 2001. An overall plan developed by Golder identified a number of remediation projects, which would be undertaken by additional partners.Work has included the construction of an acid rock drainage treatment plant, a new offshore outfall, surface water diversion and drainage measures, installation of a groundwater management system, underground rehabilitation works,and onsite management of over 50,000 cubic metres of metal-contaminated soils. Golder prepared an Overall Mine Closure and Remediation Plan for the project, and manages its implementation, including executing a major environmental monitoring and risk assessment.

“All the major remedial components are now in place,” said Gerry O’Hara, project manager, Golder Associates. “Last May, the groundwater control and management system was installed, and the water treatment plant started up last fall.”

With all the remediation work done on the water management onsite, O’Hara said the results have been visible.“Early in the project, the water quality in Britannia Creek improved about 40 times overnight with the installation of a plug in one of the mine entries – installed by UBC as part of a research program at the site,” he said. “I’ve been on this project four and a half years now, from the conceptual stage through reality, and it’s been a rewarding experience. There was a will to just get on and do the work.”

One of the most significant aspects of the remediation plan is the water treatment plant, which has been designed, built, and now operated by EPCOR. The plant uses a high-density lime sludge treatment process to raise the pH and precipitate metals, with a 1,050 cubic metre per hour design capacity. The overall project had a capital cost about $20 million.

Plant construction began in March 2005, and the first treated water was produced on October 21. Lockerbie Stanley was the building contractor, and Stantec did the engineering. “Having a design/build/operate contract allows you to move quickly,” Rector said.

An interesting feature is that the mine is being used as a reservoir, so the plant can operate in a steady state. It allows control of the inflow into the plant, reducing the variations in inflow, particularly during fall rains and spring thaw.

Three operators are onsite to run the plant, though it uses online monitoring and an advanced control system so it can be run remotely, without needing to be manned 24/7.

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