Environmental Assessment Addressing Activities Associated with Development of a Regional Wastewater Treatment Plant Ellsworth AFB, South Dakota

Ellsworth AFB is faced with having to upgrade its current wastewater treatment systems to meet more stringent State of South Dakota-mandated restrictions on wastewater discharge. Ellsworth AFB is proposing to decommission and demolish its current wastewater treatment plant and allow construction of a new sanitary sewer pipeline on Ellsworth AFB within an easement granted to the South Dakota EDA. The sanitary sewer pipeline would connect to an existing pipeline southeast of the installation that would flow to a proposed future RWWTP off-installation. In addition to evaluating these activities, this EA also evaluates Ellsworth AFB?s contribution to the regional wastewater stream. Under this Proposed Action, decommissioning of the existing WWTP would start in early 2014 and the installation would begin sending flow to the proposed future RWWTP by summer 2014. At no time during the decommissioning process would flow be untreated before the RWWTP goes online. The proposed corridor for establishing a new sewer pipeline would cross portions of the Ellsworth AFB's Prairie Ridge Golf Course and a small, unnamed tributary east of the existing WWTP. This EA has been prepared to evaluate the Proposed Action and alternatives, including the No Action Alternative, and to aid in determining whether a Finding of No Significant Impact/Finding of No Practicable Alternative (FONSI)/(FONPA) can be prepared or whether an Environmental Impact Statement is needed. Resource areas that were considered in the impact analysis are land use infrastructure, noise, air quality, safety, geological resources, water resources, biological resources cultural resources, socioeconomic resources and environmental justice, and hazardous materials and wastes. A previous iteration of this Draft EA was made available to the public for a 30-day review period in April and May 2011.