Dairy cows

Dairy cows feed at a feedlot in Sunnyside, Wash. on Monday, July 23, 2018.

A Lower Valley Dairy has agreed to make significant operational upgrades intended to better protect groundwater and soil from pollution.

Sunnyside Dairy LLC agreed to a settlement with three environmental groups — CARE, Friends of Toppenish Creek, and the Center for Food Safety — after more than a year of negotiations.

The groups sent the dairy a letter of intent to sue in February 2019, accusing the dairy of overapplying manure to fields as fertilizer, storing animal manure in leaky unlined lagoons and composting large amounts of animal waste — all in violation of the federal Solid Waste Act.

The environmental groups filed a complaint against the dairy Tuesday in U.S. District Court, but only so the proposed agreement — which is a federal consent decree — could be entered into the record for approval, said environmental attorney Charlie Tebbutt.

A story in Thursday’s Yakima Herald-Republic focused on the lawsuit but didn’t report the joint filing of the proposed agreement.

The agreement “reflects the mutual objectives of the parties to avoid litigation, if possible, and to work together in collaborative fashion to develop an agreement for raising the environmental standards at Sunnyside even further,” dairy general manager Rosalio Brambila said in a joint news release announcing the settlement.

Under the proposed consent decree, the dairy agrees to make many operational changes, including installing synthetic liners in all manure storage lagoons and groundwater monitoring wells, reducing manure applications to fields and paying $24,000 a year for residential well testing and filtration systems for homes whose water tests above nitrate thresholds considered safe for drinking.

“This consent decree will provide further protections to the Lower Yakima Valley community and requires another dairy to improve its operations to better protect groundwater,” Tebbutt said.

The proposed agreement is scheduled for a Sept. 17 hearing, but a judge could sign off on it before then, Tebbutt said.

The proposed consent decree is similar to one a handful of dairies entered in 2015 after being sued over similar complaints.

High nitrates are harmful to infants, pregnant women and elderly people, according to the Centers for Disease Control and Prevention.

Nitrates naturally occur in soil, but animal waste, heavy use of fertilizers and leaky septic tanks can drastically increase concentrations.

The lawsuit and accompanying settlement are among several the environmental groups have filed in recent years against Lower Valley dairies, which have resulted in settlement talks, Tebbutt said.

“Over a third of the milking cows owned by the big dairies in the Lower Yakima Valley are now under court-enforceable orders to stop polluting the people of the Valley,” Tebbutt said. “It will take years to see the progress from the change in manure management. In the meantime, clean drinking water will continue to be provided to as many homes as possible through these settlements.”

Reach Phil Ferolito at pferolito@yakimaherald.com or on Twitter: @philipferolito