Water on the west side of the Butte hill drains distinctly from water on the east side, which flows to the Berkeley Pit. In 1989, under EPA supervision, the Potentially Responsible Parties (PRPs) addressed rising mine waters in the West Camp/Travona Mineshaft area. Groundwater in the area rose to such a level that the lowest-elevation basements nearby in urban Butte were flooded.
The issue was addressed by pumping the West Camp to lower water levels in the old mine workings. The current West Camp water level control system, called WCP-1, pumps from 100 to 350 gallons per minute (average 200) and is piped to the Butte Treatment Lagoons, a water treatment facility that removes metals and arsenic. Pumping continues to keep the water level below the control level of 5,435 feet to prevent flooding of basements and to limit the discharge of contaminated ground water to the alluvial aquifer and Silver Bow Creek.
As noted in this EPA Bulletin from October 2010, the pump station, located near Centennial Avenue, is being upgraded with a new building, a paved road to the site, and on-site security.
Further details are available in the EPA Five Year Review Report (2011) for the greater Butte Mine Flooding Operable Unit (BMFOU). Download that report and associated Appendices, as the Record of Decision (ROD) for the BMFOU, which includes the West Camp, at the Superfund Library.
The most recent EPA Bulletin (Feb. 2012) about the West Camp can be downloaded below.