Prior Government Actions
The US EPA estimates 20 percent of the original volume of Torch Lake is filled with stamp sand. Extensive stamp sand deposits are present around the western shore of Torch Lake, and at the north entry of the Portage Waterway. Stamp sand is widespread elsewhere on the Keweenaw, covering miles of Lake Superior shoreline, large areas of inland lakes and streams, and have been used to “make land” in areas that are now residential subdivisions or commercial enterprises. Due to legislative amendments that became effective in early 2015, stamp sand and slag are not subject to regulation under Part 201, Environmental Remediation, of Act 451, Natural Resources and Environmental Protection Act, as amended.
US EPA and EGLE RRD Superfund Section Actions
The EGLE RRD Superfund Section and the US EPA have stabilized many areas (totaling over 800 acres) in the Torch Lake Superfund Site. However, the mass of stamp sand on the bottom of inland lakes has been left for natural recovery. The EGLE RRD Superfund Section has indicated natural recovery is estimated to take in excess of 800 years.
EGLE Water Resources Division (WRD)
In addition to the abandoned mining wastes disposed of in the Project area footprint, historic mining operations produced wastes that were disposed of in waters of the state including the Portage Canal, Lake Superior, Torch Lake, and inland waterways. “Stamp sand,” the finely crushed waste materials from stamp mills, is the most obvious waste material. Being crushed rock, stamp sand is coarse, angular, lacks organic content, is extremely well drained, and extremely physically abrasive. Stamp sand was discharged in huge volumes – dozens of millions of metric tons.
As stamp sand contains materials that may be toxic to aquatic organisms and are physically unsuitable as aquatic habitat, the EGLE WRD has taken action at several inland sites. The WRD obtained funding for remedial activities and has stabilized several deposits.
At Gay, about 90 percent of the 23 million metric tons of stamp sands initially deposited there have already washed down drift as far as the Traverse River (nearly 5 miles) or out into Lake Superior. In 2013, these stamp sands covered 1400 acres upland and 1000 acres sub-aqueous.