It was a dark and stormy night To get out of the bad weather a group of migrating geese stopped to rest on Lake Berkeley in Montana The next morning 342 birds floated dead on the water The water had eaten through their insides Lake Berkeley sits on top of an old copper mine When the mine closed in 1982 groundwater began to seep in Sulfides from the surrounding rocks mixed with the water to form sulfuric acid Now the lake has a pH of 2 5 it is as acidic as lemon juice When employees of the Bureau of Mines go out on the water they take a fiberglass boat An aluminum boat might dissolve leaving them stranded in the water As if the acidity weren t bad enough the water also contains high concentrations of dissolved metals like copper cadmium and arsenic In fact there is so much dissolved copper that a nearby company mines directly from the water removing up to 400 000 pounds of copper a month To do this they line canals with scrap iron and direct the Berkeley water through The copper ions trade places with the iron in this single replacement reaction Lake Berkeley is the largest contaminated body of water in the United States No fish swim beneath the brownish red surface No plants grow along the lake s yellow shores When birds land on the water now park rangers use gunfire or heavy metal music to scare them away For a long time it was assumed that nothing could live in such toxic water But in 1995 the same year as the birds deaths a green slime was found on a rope in the water Since then over 100 different bacteria algae and yeast have been found in the lake Some of these cells have been seen nowhere else on Earth These creatures may be the key to cleaning up the water One species of lake yeast can absorb 80 of the metals found in the water When the yeast die they sink to the lake floor taking the trapped metals with them Several species of algae produce bicarbonate a basic compound that would neutralize the acidic water Once the lake conditions improve larger organisms could then use the algae as a food source The water in Lake Berkeley continues to rise 6 to 8 inches a month By 2022 or 2023 the water will have risen to a point that it will contaminate local aquifers and groundwater It is unlikely that nature or man will have figured out a way to clean up the lake in time Questions 1 Describe the chemistry of Lake Berkeley What caused these conditions 2 What organisms live in Lake Berkeley Why is this surprising 3 How could the organisms living in Lake Berkeley help clean up the lake