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Sarah Kanouse, Environmental monitoring infrastructure visible inside the Rocky Flats National Wildlife Refuge, 2 June 2014, Flickr

Issue Brief

Military to Wildlife Conversions

Military to Wildlife Conversion (M2W) is the process of reclassifying former U.S. military bases as national wildlife refuges. The DOD oversees the United States military, while the DOE’s duties include overseeing nuclear weapons production.During this process, the Department of Defense (DOD) and Department of Energy (DOE) transfer custody of military sites to the Department of the Interior’s (DOI) Fish and Wildlife Service (FWS). The FWS is charged with environmental conservation and the protection of plant and animal species on federal lands. U.S. Fish and Wildlife Service, National Wildlife Refuge System, “Refuge List by State,” https://www.fws.gov/refuges/profiles/ByState.cfm?state=CO.As of 2020, there are eight national wildlife refuges in Colorado. Rocky Mountain Arsenal was a DOD-operated chemical weapons plant that became a national wildlife refuge in 1992. Rocky Flats was a DOE site that produced plutonium detonators for nuclear weapons; it was designated as a national wildlife refuge in 2001 and came under the administrative purview of the U.S. Fish and Wildlife Service in 2007. Both sites are located near Denver, CO.Two of these refuges, Rocky Mountain Arsenal and Rocky Flats, are former military bases and weapons manufacturing plants respectively. These sites exemplify the major issues surrounding M2W, including post-Cold War contamination and the interplay of military and environmental interests.

M2W is one option for military bases undergoing closure. Bases might be closed due to financial burden, obsolete technology and infrastructure, contamination, or lack of need. Arms reduction treaties and slackening Cold War tensions between the United States and Soviet Union contributed to the closure of many bases in the late 1980s. Since 1988, four hundred DOD sites have been closed or reclassified under the federal Base Realignment and Closure (BRAC) commission. Still more military sites have seen closure or conversion under the DOE’s Office of Legacy Management and its environmental remediation efforts. To date (2020), more than fifteen percent of closed military bases have been slated for conversion to national wildlife refuges.

Sites selected for M2W are often severely contaminated. Pollutants from chemical and nuclear weapons plants may be carcinogenic (causing cancer), mutagenic (causing genetic mutations), and/or teratogenic (causing birth defects). These pollutants make their way into the soil, groundwater, and air surrounding the sites. Rocky Mountain Arsenal and Rocky Flats are both notorious for the pollution they caused during their operations. For 40 years, Rocky Mountain Arsenal produced rocket fuels, explosives, and chemical weapons, including but not limited to mustard gas, chlorine gas, Lewisite, napalm, and VX nerve agent. Shell Chemical (now Shell Oil) produced commercial chemical products at the site as well. The two entities produced so much pollution that in 1974, the Colorado Department of Public Health and Environment (CDPHE) ordered them to cease polluting ground and surface waters. Litigation between the U.S. Army (on behalf of Rocky Mountain Arsenal), the state of Colorado, and the Environmental Protection Agency (EPA) persisted into the twenty-first century.

More infamous still is Rocky Flats, which officially operated as a nuclear weapons plant from 1952 to 1989 (production actually continued until 1992). The site of two major plutonium fires in 1957 and 1969, as well as a number of other accidents, Rocky Flats was once labeled by the DOE as the “most dangerous weapons plant in the nation” because of its rampant contamination of land and workers. In June 1989, the FBI conducted a raid of Rocky Flats on suspicion of its violating the Resource Conservation and Recovery Act, the Clean Water Act, and other federal environmental laws.

Given the destructive history of facilities like Rocky Mountain Arsenal and Rocky Flats, environmental conservation seems like an unlikely enterprise. Yet Rocky Mountain Arsenal was designated as a national wildlife refuge in 1992. In 1989, the EPA formally added Rocky Flats to the National Priorities List of the nation's most contaminated sites, but by 2001 Rocky Flats had also become a national wildlife refuge. Under BRAC, twenty-one DOD sites have been reclassified as national wildlife refuges, amounting to more than 1.1 million acres of converted land. The DOE has also signed sites over to the FWS for conversion to wildlife and research parks. The rationales for conversion vary. Some sites have high biodiversity due to their extensive buffer zones, which historically protected them from civilian access and development. Environmental interest groups might act to preserve this biodiversity, as was the case when bald eagles were discovered at Rocky Mountain Arsenal. Some groups argue that if sites are too contaminated for human development, then they might as well be put to use as conservation land. Still others argue that nature can repair all things, even nuclear destruction wrought by humans. These claims fail to acknowledge lingering dangers of contamination, as well as the military’s continual degradation of the environment, instead depicting the United States military as environmental steward—a dubious role given its history of environmental violations.


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