For the first time since 1982, the Berkeley Pit is not collecting water.

About three million gallons a day are being pumped out, which is roughly the equivalent of the groundwater and stormwater that goes in.

Montana Resources started pumping and treating the most contaminated water body in the nation last week.

Mark Thompson, MR vice president for environmental affairs, said the mine company has been testing the pumping and treating of Berkeley Pit water since sometime in March, but this is the first week the mine has let the water run through the mine’s new wastewater treatment system consistently.