By EMILY SCHABACKER/ Montana State News
Toxic water levels approach maximum capacity in Butte’s Berkeley Pit, potentially threatening the city’s groundwater system by 2023. Montana’s environmental advocacy groups have started looking for clean up or containment methods for the abandoned copper mine.
After the mine closed in 1982, rain and groundwater flooded underground shafts, forcing contaminated water to accumulate in the pit. The acidic pond stretches one mile long by a half mile wide and reaches down more than 1,700 feet.
Current water levels reach 5,336 feet above sea level, 74 feet below maximum capacity as determined by the U.S. Environmental Protection Act, according to the website Pit Watch: Berkeley Pit News and Info.
If water levels surpass the capacity line by 50 feet, “the pit and mine water could enter the city’s groundwater,” according to an article from physics.org. Water levels in the pit rise 2 million gallons of water a day or 5 to 6 feet every year, according to vice president of HR at Montana Resources Mike McGivern.
In 2000, the EPA and Montana Resources slowed the rising water levels by building a water treatment plant that processes about 4 million gallons of water a day. Once the water is cleaned, it is either recycled to other Montana Resource mine sites or, according to McGivern, discharged into Silver Bow Creek.
The plant will need to process up to 7 million gallons a day by 2023 in order to prevent overfill. McGivern said that the treatment plant will undergo an adequacy review in 2021 to determine if the plant is “up to the job.”
Daryl Reed from the Department of Environmental Quality and Waste Management assures Montana residents that the pit will not overflow. Reed said, “Currently, there is no completed exposure pathway that threatens Butte’s fresh water supply.”
However, some Butte residents feel differently. According to an article published on the Fox News website, community advocates feel the water treatment plant does not provide a long-term solution. Some feel the Berkeley Pit will negatively affect the town economically, socially, and environmentally.
– edited by Samantha Sundly