Question: What Geologically classified as a "massive sulfide ore deposit", uses an earthfill dam on Spring Creek primarily to collect severe acid mine drainage stemming?
Related documents: [0]  [DOC] Iron Mountain Mine, also known as the Richmond Mine at Iron Mountain, is a mine near Redding in Northern California, US. Geologically classified as a "massive sulfide ore deposit", the site was mined for iron, silver, gold, copper, zinc and pyrite intermittently from the 1860s until 1963. The mine is the source of extremely acidic mine drainage which also contains large amounts of zinc, copper and cadmium. One of America's most toxic waste sites, it has been listed as a federal Superfund site since 1983. [END] 
[1]  [DOC] Spring Creek Debris Dam is an earthfill dam on Spring Creek, a tributary of the Sacramento River, in Shasta County in the U.S. state of California. Completed in 1963, the dam, maintained by the U.S. Bureau of Reclamation, serves primarily to collect severe acid mine drainage stemming from the Iron Mountain Mine. The dam forms the Spring Creek Reservoir, less than 1 mi long. Spring Creek and South Fork Spring Creek flow into the reservoir from a 16 sqmi watershed. The dam is directly upstream from the city of Keswick, California and the Keswick Reservoir. [END] 
Answer: 
Iron Mountain Mine
Iron Mountain Mine