EPA seeks source of pollution in Valley wells

Improved water quality monitoring and better identification of vulnerable ground water supplies are among the needs listed in a report released today that outlines options for dealing with pollution in private drinking wells in the Lower Yakima Valley.

Government agencies also need to find funding options to support initiatives to better manage potential ground water contamination and improve water quality, said the report released by the federal Environmental Protection Agency, Yakima County and the Washington departments of agriculture, ecology and health.

The report distributed and posted by the agencies outlines options for addressing high levels of nitrates and bacteria that are found in shallow aquifers throughout the Lower Valley.

The report covers areas stretching from Sunnyside and Grandview to the east. While not all ground water supplies have been affected, the report said nearly 2,000 people in the area have been exposed to nitrate levels over the maximum contamination level in their drinking water.

Nitrogen is a nutrient in many commercial fertilizers, and the mobile form, nitrate, is found along with bacteria in manure and liquid waste from septic tanks. If nitrate leaches through soil and into aquifers, it can contaminate drinking water supplies.

Elevated nitrate levels can pose a hazard to babies, pregnant women and people with a rare blood enzyme disorder, according to the state Department of Ecology. Fecal bacteria, such as E. coli, also can cause illnesses.

The agencies over the past year have worked with the community, businesses, agricultural producers and the Yakama Nation to identify ways to address nitrate and ground water contamination in the Valley, according to Ecology.

Two challenges facing the agencies in their search for a management solution have been cross-jurisdictional responsibilities and the fact that property owners are responsible for the upkeep of private wells, the state said.

EPA is beginning to sample ground water in the Lower Valley to find the source of contamination.

Residents there have been complaining about nitrate and bacterial pollution in private wells.Many believe the problem mainly is caused by the application of dairy manure and commercial fertilizer to crops.

Tom Eaton, director of EPA's operations in Washington, said the agency is assembling all available information to identify possible sources of contamination and has started a sampling program.

In response to recommendations made in the report, Yakima County commissioners have expressed interest in establishing a local ground water management area to bring focus to the cleanup.

The report recommends local leaders form a coordinating body or petition the EPA to designate the area as a sole source aquifer. Both models have been used in other parts of the state to address aquifer protection and cleanup, according to the state.

The state Department of Agriculture will continue working with dairy farms to ensure they are properly managing manure applications.

* On the net: More information and a copy of the report is available at