History by Ron Eber of the campaign to prevent mining at Rock Mesa in the Three Sisters Wilderness. From 1963 to 1983, environmental activists and organizations including Friends of Three Sisters, the Sierra Club, the Oregon Environmental Council, and the Oregon Wildlife Federation lobbied the U.S. government to invalidate mining permits that the U.S. Forest Service had granted in 1961 for pumice rock mining at Rock Mesa. In July 1983, the Forest Service purchased all the mining claims.