— Two environmental groups have sued another Lower Yakima Valley dairy for alleged groundwater pollution.

Outlook-based Community Association for the Restoration of the Environment and the Washington, D.C.-based Center for Food Safety filed a lawsuit Wednesday in U.S. District Court against Haak & Sons Dairy of Outlook, saying the dairy allowed manure to contaminate the drinking water in private, residential wells.

Last week, the groups sued four other Lower Yakima Valley dairies — Liberty-Bosma Dairy, Cow Palace, D&A Dairy and the George DeRuyter and Sons Dairy, all located in Yakima County north of Granger and Sunnyside.

The dairies have 20 days to respond to the suits.