The Story Behind Montana's Acid Lake Will Fascinate You
Did you know Montana has something that’s often called an “acid pit of doom?”
The Berkeley Pit is a former open pit copper mine located in Butte. It’s filled with water that is heavily acidic, laden with heavy metals, rich with dangerous chemicals, and just a real problem in general.
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When the pit was closed, the water pumps in the nearby Kelly shaft were turned off. Groundwater from the surrounding aquifers began to fill the pit slowly, rising at a rate of about one foot per month.
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This presents a major environmental problem. The water, with dissolved oxygen, makes the minerals in the ore and wall rocks decay. This releases the acid.
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The water has the acidity of cola or lemon juice.
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This will reverse flow back into surrounding groundwater, polluting Silver Bow Creek, the headwaters of the Clark Fork River. Needless to say, this would be a disaster.
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Sadly, they died horribly, and that’s when it was discovered that the water was acidic enough to eat away at the intestines of anything that drank enough of it.
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For $2, you can step out on a viewing platform and see it for yourself.
The Berkeley Pit is a small part of Butte’s fascinating history. When you’re there, make sure to check out the World Museum of Mining.
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