Preliminary Technical Evaluation of Three Reports by U.S. Environmental Protection Agency Region 10 on Nitrate in Water Wells, Yakima River Basin, Yakima County, Washington

The Yakima Valley is a large agricultural area where there are multiple potential sources of nitrate in groundwater.  Potential sources are intermingled, i.e., homes with septic systems are on the same properties as the dairies or adjacent to farms and/or dairies.  In 2012, Region 10 of the US Environmental Protection Agency undertook a study to source track and identify nitrogen sources in the Yakima River Basin as part of an enforcement effort focusing on dairies.…