Yakima County, Wash., dairyman Dan DeRuyter said he wants to stay in business, but he’s not sure how long he can fight the Environmental Protection Agency.

Two neighboring dairies, also being sued by the EPA for allegedly endangering public health, have or will close. Liberty Dairy sold its cows last fall. Cow Palace Dairy plans to sell this spring.

That will leave the DeRuyter dairy, started by Dan’s father, George, in 1972, as the sole survivor in a 12-year effort by the dairies to satisfy the EPA they are doing everything required of them to keep manure from spiking nitrate levels in the aquifer.

“I try to be optimistic, but there are a lot of dark clouds, and a lot of uncertainty. I really don’t know how to feel at this point,” DeRuyter said March 25.

The Yakima Valley has numerous sources of nitrates, including farms and other dairies. The EPA singled out for special attention a cluster of large dairies more than a dozen years ago.

DeRuyter and the other dairies signed an agreement with the EPA in 2013 committing to minimize manure seeping into groundwater. The EPA sued in June claiming the dairies broke the agreement and is seeking civil penalties of up to $29,154 a day. The dairies deny the allegations.

No court has thoroughly sorted out the conflicting claims, but U.S. District Judge Thomas O. Rice in Spokane issued a preliminary injunction in December, finding the EPA was justified in claiming public health was in imminent danger.

Rice ordered the dairies to test more wells and provide residents downgradient of the diaries with drinking water. The dairies say they already are testing wells and supplying drinking water.

The dairies are appealing Rice’s ruling to the 9th Circuit Court of Appeals. The EPA and dairies recently agreed to a truce until Aug. 11 to see whether they can work out a settlement.

DeRuyter said he doesn’t know whether the Trump EPA will view the case differently than the Biden EPA.

“I don’t know about that. All I’m looking for is to be treated fairly,” he said. “Being treated fairly would be acknowledging what we’ve done.”

DeRuyter said his dairy, which milks 5,300 cows, has spent more than $10 million to fulfill its agreement with the EPA and has endured far more scrutiny than other dairies.

“I’m not sure what else we can do. We’re already done everything they’ve asked us to do,” he said. “If we are to stay in business, we need to be treated like any other dairy farm.”

When the Cow Palace closes the Yakima Valley will lose more than 100 jobs. DeRuyter said he also has more than 100 employees. Many have worked at the dairy for more than 20 years, he said.

“The people I work with are very loyal to me, and I am loyal to them. I don’t want to give up, not with all the blood, sweat and tears these guys have put into it.”