The Cow Palace dairy in Yakima County, Wash., embroiled in a prolonged battle with the Environmental Protection Agency for allegedly polluting groundwater, will close.

Owner Adam Dolsen, whose grandfather started the dairy in 1972, said March 12 that closing the dairy is the hardest decision he’s ever made, but he couldn’t see how he could ever satisfy the EPA.

“It’s really a frustrating group to work with. Their goal is to drive us out of business,” Dolsen said. “I’m spending a ton of money on attorneys every month, and I don’t know where this ends.”

The dairy plans to close in May, putting more than 120 employees out of work. The dairy will sell its 7,500 milking cows.

Washington State Dairy Federation policy director Jay Gordon said the EPA placed unreasonable demands on the dairy.

“I hope the EPA is happy,” Gordon said.

“It’s sad. It’s really, really sad,” he said. “They are one of the most amazing dairy families in the state.”

The EPA declined to comment.

The dairy has been dogged by EPA allegations for more than a decade. Cow Palace and three other dairies entered into agreement with the EPA in 2012 to contain manure.

The EPA filed a new lawsuit last June accusing the three surviving dairies of not doing enough to keep excessive nitrates from seeping into the aquifer. Liberty Dairy closed in October.

U.S. District Judge Thomas Rice ruled in December elevated levels of nitrates in drinking water were an “extreme danger” to public health and ordered Cow Palace, Library and DeRuyter dairies to do more to test area wells for nitrates and supply drinking water to residents.

The dairies argued they had already spent millions of dollars to comply with their agreement with the EPA.

“When we read that decision we thought about how every lawsuit will go back to Rice,” Dolsen said. “We knew we would just continue to lose.”

The dairies appealed Rice’s ruling to the 9th Circuit Court of Appeals. The EPA and diaries recently agreed to stay proceedings until at least August to give the sides time to negotiate a settlement.

Dolsen said he felt like further negotiations would put in the same spot he’s been in. “I just feel like I’m setting myself up for another eight- to 10-year agreement,” he said. “Where we are right now, it’s not a viable situation.”

Save Family Farming, a Washington advocacy group, issued a statement criticizing the EPA. “EPA Region 10 attacks have now claimed three of the four dairies they began targeting over a decade ago,” the statement read.