EPA settles with Hilmar Cheese for Safe Drinking Water Act violations

On Monday, the U.S. Environmental Protection Agency (EPA) announced a settlement with Hilmar Cheese Company Inc. for Safe Drinking Water Act violations at its facility in Hilmar, California, located in the San Joaquin Valley. The company will pay a $92,000 penalty for findings of permit violations related to the Underground Injection Control Program.

“Facilities that include underground injection in their operations must comply with all permit conditions in order to protect underground sources of drinking water,” said EPA Pacific Southwest Enforcement and Compliance Assurance Division Director Amy Miller. “Ensuring that businesses comply with our regulations is critical to preserving vital groundwater resources.”

Injection wells are used to place fluid underground into porous geologic formations for storage or disposal. The Underground Injection Control Program works with injection well operators throughout the life of an injection well to confirm their practices do not contaminate drinking water. EPA conducts inspections to verify well operator compliance with the injection permit or applicable requirements.

EPA classifies injection wells into one of six types. Hilmar Cheese Company is currently permitted to operate two Class I Non-Hazardous underground injection wells at its facility and is permitted to inject non-hazardous “Class I” fluids associated with its cheesemaking operations. These non-hazardous fluids include brine (salt water), facility wastewater, concentrated salt, and chemical additives (which must be approved by EPA) for the purpose of facility and injection well operation and maintenance.

EPA performed a virtual inspection of the facility in March 2021, and made findings of permit violations that included failure to:

1. Report changes in pressure within the casing/tubing annulus for both injection wells;
2. Maintain a minimum pressure of 100 psi on the annular space of one of its injection wells;
3. Report data as required by the facility permit over two months.

This enforcement action helps ensure continued operation at the Hilmar Cheese Company’s facility complies with its underground injection control permit and avoid contamination of underground sources of drinking water.

Read the public notice for the proposed settlement here.