Gilman began in the late 1800's as a silver mining town. Zinc and copper were also mined here. In the 1960's the town had a population of a few hundred, but by the 1980's the town and mine was closed down. After the closure of the mine and the abandonment of the town, a 235-acre (0.95 km2) area, which included 8 million tons of mine waste, were designated a Superfund site by the EPA and placed on the National Priorities List in 1986.