Midnite Mine is an inactive former uranium mine in the Selkirk Mountains of eastern Washington. Located within the reservation of the Spokane Tribe of Indians, the mine was operated from 1955 until 1981.
Two open pits, backfilled pits, and a number of waste rock piles and ore/protore stockpiles remain on site. In addition to elevated levels of radioactivity, heavy metals mobilized in acid mine drainage pose a potential threat to human health and the environment. The site drains to Blue Creek, which enters the Spokane Arm of Franklin D. Roosevelt Lake. Contaminated water emerging below the waste rock and ore piles is currently captured for treatment in an on-site treatment system.
Source US EPA