The Department of Energy (DOE) prepared this Environmental Assessment (EA) to evaluate the potential environmental consequences of providing a financial assistance grant under the American Recovery and Reinvestment Act of 2009 (Recovery Act) (Recovery Act; Public Law 111-5, 123 Stat. 115) to Battelle Memorial Institute to facilitate the installation of 540 additional solar panels, 10 solar concentrating modules, and 8 small wind energy systems at the City of Ellensburg's Renewable Energy Park located in Ellensburg, Kittitas County, Washington. This EA analyzes the potential environmental impacts of DOE's proposed action of providing the Recovery Act funding and of the No-Action Alternative. In this EA, DOE evaluated impacts to air quality, noise, aesthetics and visual resources, soils and geology, water resources, biological resources, and cultural resources. After performing a screening analysis of other environmental resource areas, DOE concluded that impacts to some aspects of the environment would not be likely to occur or would be negligible. The proposed project would be designed in compliance with federal and state air quality regulations, would reduce greenhouse gas emissions, and would have a net beneficial impact on air quality in the region. Operation of the concentrating solar modules and eight small wind systems would cause a negligible increase in noise outdoors near the adjacent interstate and Recreation Park. The aesthetics of the City of Ellensburg's Renewable Energy Park would change with the addition of ten 18-foot diameter solar concentrating modules and eight wind towers ranging from 40 to 100 feet in height; however, these changes would be in compliance with the City and County proposed regulations for wind turbines. Adverse impacts to visual resources would be minimal. There would be no adverse impacts to the 100-year floodplain profiles associated with Reecer Creek, and no increase in risk to lives or property in the area from the project. Developing 3 acres for further construction of the Renewable Energy Park would not adversely impact any plant or animal species because the project site is small and isolated from larger tracks of undisturbed land, and because plant and animal species found there are common and widespread in the region. The risk of collisions between the wind turbines and migratory birds and bats is not likely due to the configuration of the turbines (parallel to bird movements toward the wetlands and grouped configuration), the relatively short height of the turbines, and placement in previously disturbed habitat. In support of this EA, a cultural resources inventory was conducted for the area of potential effect (project site). No archaeological resources were identified, and DOE determined that no historic properties would be affected by Battelle's project. In summary, expanding the Renewable Energy Park with additional solar panels, solar concentrating modules, and small wind turbines would not likely result in significant adverse environmental impacts, particularly considering the other existing surrounding uses.