The proposal to resume mining and barge loading activity at the Maury Island site calls for replacing an existing dock and conveyor, which has 228 wood pilings treated with creosote, with a new steel dock. The new dock is designed in accordance with the state Department of Fish & Wildlife guidance for over-water structures. It will stand higher above the water, to reduce shading, and will extend into deeper water where eelgrass does not grow to further minimize impacts. The new conveyor will be enclosed to prevent material spillage.
The mine boundary has been revised to protect the bluffs, preserve Madrone forest, and minimize visual impacts. Soil contaminated in the past by arsenic emissions from a copper smelter near Tacoma will be handled and contained using methods and criteria approved by the Washington State Department of Ecology, making the mine site the largest area on the island to undergo voluntary remediation at no cost to taxpayers.
The proposed mining actions include mining up to 193 of the site’s 235 acres. A 50-foot-wide vegetated buffer will be maintained around the site perimeter, and the mine boundary will be set back to protect the bluffs along the shore of Puget Sound, keeping a one-mile section of shoreline intact and undisturbed for the life of the mine. A 15-foot buffer, more than three times that required at some mines, will be maintained at all times above the groundwater table.