October 1, 2007
Nearly a quarter century in the making, a major milestone at the Milltown Reservoir Sediments Superfund site will be reached this week with the first shipment of wastes to the BP-ARCO repository in Anaconda-Deer Lodge County.
The sediments have been excavated from the bypass channel, which is now nearly complete, and will be shipped starting Tuesday, October 2 via Montana Rail to the repository, a part of the Anaconda Smelter Superfund Site.
With the first shipment, Envirocon, the project contactor, will begin a seven days a week schedule, except for time off at holidays. At one train load per day, Envirocon estimates it will take 800 days to ship more than two million cubic yards of Milltown sediments to the repository.
Under the current schedule, 45 railcars, each capable of carrying 70 cubic yards (or about 100 tons) will be loaded during the day and then shipped that night. The next day Envirocon will use excavators to unload the railcars and 40 ton haul trucks to transport the sediments to cells on the eastside of the repository. The sediments, high in contaminants like arsenic, copper and zinc but also full of organic matter, will be spread with bulldozers into a layer at least 22 inches thick over existing smelter wastes at the repository and then prepared for revegetation.
For more information, see the EPA news release (PDF) and weekly update (PDF). Also see the Associated Press coverage, the Missoulian, and New West.
The Milltown Reservoir at the confluence of the Blackfoot and Clark Fork Rivers was designated a Superfund site in 1983 after local health officials found that the Milltown aquifer was contaminated with arsenic from mine wastes that had washed down the Clark Fork River in 1908.