Colorado cleaned up Rocky Mountain Arsenal; refuge now supports more than 330 animal species

Rocky Mountain Arsenal National Wildlife Refuge Just 10 miles northeast of Denver, Colorado, the Rocky Mountain Arsenal National Wildlife Refuge is now a vast urban wildlife sanctuary where bison graze, bald eagles fly over lakes and black-footed ferrets live in the grasslands. Covering about 15,000 acres, the refuge is home to more than 330 species of mammals, birds, reptiles, amphibians and fish.But the landscape once had a very different purpose. According to University of Colorado, Denver, in 1942, during World War II, the US Army selected about 17,000 acres of farmland in Commerce City for the production of chemical weapons and rocket fuel. From the 1950s through the 1980s, facilities at the Arsenal were also leased to Shell for pesticide production.Decades of chemical manufacturing left the land and groundwater heavily contaminated. More than 600 chemicals were identified at the site, which was placed on the Superfund National Priorities List in 1987.Millions of pounds of toxic waste were dumped at the Arsenal over the years, while several major spills were recorded. A 1947 spill released about 100,000 gallons of benzene. In 1978, another incident involved 58,864 gallons of d...