This last winter, while still in Bonaire, Barb and I read two interesting books by Timothy Egan. So interesting, that they have influenced our travel plans as we head west. One, Lasso the Wind: Away to the New West, is a social history, with each chapter dedicated to a particular site in the western states. One of the chapters is about the rape of the environment in Butte, Montana. We vowed to see for ourselves. This posting is about that visit.
(The other book is The Big Burn, and that will relate to a later post in our blog.)
From Wikipedia, the free encyclopedia
The Berkeley Pit is a former open pit copper mine located in Butte, Montana, United States. It is one mile long by half a mile wide with an approximate depth of 1,780 feet (540 m). It is filled to a depth of about 900 feet (270 m) with water that is heavily acidic (2.5 pH level), about the acidity of cola or lemon juice. As a result, the pit is laden with heavy metals and dangerous chemicals that leach from the rock, including copper, arsenic, cadmium, zinc, and sulfuric acid.
The mine was opened in 1955 and operated by Anaconda Copper and later by the Atlantic Richfield Company (ARCO), until its closure on Earth Day 1982. When the pit was closed, the water pumps in the nearby Kelley Mine, 3,800 feet below the surface, were turned off, and groundwater from the surrounding aquifers began to slowly fill the pit, rising at about the rate of one foot a month. Since the pit closure in 1982, the level has risen to within 150 feet of the natural groundwater level.
The pit and its water present a serious environmental problem because the water, with dissolved oxygen, allows pyrite and sulfide minerals in the ore and wall rocks to decay, releasing acid. When the pit water level eventually reaches the natural water table, estimated to occur by around 2020, the pit water will reverse flow back into surrounding groundwater, polluting into Silver Bow Creek which is the headwaters of Clark Fork River. The acidic water in the pit carries a heavy load of dissolved heavy metals. In fact, the water contains so much dissolved metal (up to 187 ppm Cu) that some material is mined directly from the water.
In the 1990s plans were devised for solving the groundwater problem. Water flowing into the pit has been diverted to slow the rise of the water level. Plans have been made for more extensive treatment in the future. The Berkeley Pit has since become one of the largest Superfund sites.
The pit is currently a tourist attraction, with an adjacent gift shop. A $2 admission fee is charged to go out on the viewing platform.
From other sources:
Butte is the largest U.S. Environmental Protection Agency (EPA) Superfund site in America. It is their job, along with the Montana Bureau of Mines and Geology and other groups, to maintain it as a terminal sink and keep the pathogens contained to help the public stay safe and healthy. Water levels in the East Camp/Berkeley Pit system will not be allowed to exceed the established Safe Water Level (SWL) of 5,410 feet
- Within eight years of approaching the SWL, design of final water-treatment plant shall begin, with construction completed four years prior to the projected date for water to reach SWL. This will allow for a shake-down period, for optimizing plant operations.
- Long-term, ground-water and surface-water monitoring program will be implemented.
An estimated 3,000 to 4,000 snow geese perished in December 2016 in the Berkeley Pit’s toxic water, sucumming from both heavy metals and sulfuric acid, according to U.S. Fish and Wildlife Service. The companies responsible for the pit, Montana Resources and Atlantic Richfield Co., could be fined as much as $5,000 per bird. The report says the birds’ condition was similar to the 342 snow geese that died in November 1995 when a flock landed — almost 21 years to the day — on the pit during a snowstorm and perished.
From the time it was located in 1875 until it was purchased by Marcus Daly and associates in 1879, ownership of fractional shares in the Orphan Girl Mine changed hands many times. The Orphan Girl eventually operated to a depth of over 3,000 feet. While not a huge producer according to Butte standards, by 1944 hardrock miners had removed a respectable 7,626,540 ounces of silver as well as lead and zinc from her depths. Cool temperatures between 55 and 65 degrees made the Orphan Girl—affectionately nicknamed “Orphan Annie” or “the Girl”—a desirable place to work unlike some “hot boxes” where temperatures could top 100 degrees. By the end of the 1920s, the Anaconda Company owned the Girl and operated it until the 1950s. In 1965, the Girl became the site of the World Museum of Mining with its stated mission to preserve the history of mining and the cultural heritage of attendant mining communities. Many of the original structures are still visible, including the 100-foot-tall headframe and the Hoist House, which houses exhibits as well as original equipment. Visible are the cages that were crammed with six or seven miners for their daily trip 2700-feet down the shaft.
The World Museum of Mining’s most prominent feature, besides offering underground mine tours of The Orphan Girl Mine, is the “composite re-creation of an Old West mining town, called Hellroarin’ Gulch.” There are fifty exhibit buildings, with sixty-six exhibits in the mining yard alone, that revolve around not only mining, but the ethnic and culture groups that worked in this dangerous profession It is described as “an authentic reproduction of an 1890’s mining camp. Buildings include a bank, funeral parlor, jail, post office, city hall, union hall, school, the sauerkraut factory, saloon, and Chinese laundry.
The highlight of our visit was the trip down into the mine using a special entrance created by the School of Mines for the Museum. Accompanied by a guide, our group descended some 65 feet. Although the original shafts were some 2700 feet deep, that is no longer possible, since the shafts are now flooded to a depth of about 100 feet.