Environmental assessment for the Hoe Creek underground, Coal Gasification Test Site Remediation, Campbell County, Wyoming

The U.S. Department of Energy (DOE) has prepared this EA to assess environmental and human health Issues and to determine potential impacts associated with the proposed Hoe Creek Underground Coal Gasification Test Site Remediation that would be performed at the Hoe Creek site in Campbell County, Wyoming. The Hoe Creek site is located south-southwest of the town of Gillette, Wyoming, and encompasses 71 acres of public land under the stewardship of the Bureau of Land Management. The proposed action identified in the EA is for the DOE to perform air sparging with bioremediation at the Hoe Creek site to remove contaminants resulting from underground coal gasification (UCG) experiments performed there by the DOE in the late 1970s. The proposed action would involve drilling additional wells at two of the UCG test sites to apply oxygen or hydrogen peroxide to the subsurface to volatilize benzene dissolved in the groundwater and enhance bioremediation of non-aqueous phase liquids present in the subsurface. Other alternatives considered are site excavation to remove contaminants, continuation of the annual pump and treat actions that have been used at the site over the last ten years to limit contaminant migration, and the no action alternative. Issues examined in detail in the EA are air quality, geology, human health and safety, noise, soils, solid and hazardous waste, threatened and endangered species, vegetation, water resources, and wildlife. Details of mitigative measures that could be used to limit any detrimental effects resulting from the proposed action or any of the alternatives are discussed, and information on anticipated effects identified by other government agencies is provided