The state Board of Health is considering scrapping a little-known rule that prohibits the accumulation of manure in places where it might harm water quality, such as groundwater used by private well owners.

"It's an old rule so it's time we looked at it," said Ned Therien, health policy analyst with the state board in Olympia.

But citizen groups that oppose large, concentrated livestock operations, particularly dairies, say the rule could be a powerful tool to regulate what they believe is a major source of contamination in many rural, Lower Yakima Valley wells.

Jan Whitefoot, spokeswoman for Concerned Citizens for the Yakama Reservation, said state and local health officials should have been using the rule all along to protect groundwater.

"I feel betrayed. Health officials are supposed to be working with us on clean-water issues and not once did they tell us they had this kind of jurisdiction," Whitefoot said Monday in a telephone interview.

Whitefoot and Community Association for the Restoration of the Environment (CARE) of Granger have been trying to directly link dairy manure from storage lagoons and application as fertilizer to high levels of nitrates in many private wells.

So far, water-quality officials with local, state and federal government agencies have declined to single out dairies, saying commercial fertilizer, faulty septic systems and old wells are also sources of the problem.

The U.S. Environmental Protection Agency has been leading a months-long task force that is close to recommending solutions to a water-quality problem that for years has been plaguing many poor, rural residents dependent on unregulated wells.

The Board of Health rule is under a section of the Washington Administrative Code titled "Keeping of animals." It says in part that, "Manure shall not be allowed to accumulate in any place where it prejudicially affects any source of drinking water."

The three-part rule requires "any person, firm or corporation" from keeping animals in a manner that constitutes a nuisance. In "populous districts," waste is supposed to be contained in a water-tight pit or chamber and removed once a week during the warm months of the year.

Local health districts enforce the rules of the state Board of Health.

Gordon Kelly, environmental health director for the Yakima Health District, said the rule is aimed at preventing nuisance situations at hobby farms, not large-scale commercial operations.

"This is used almost exclusively where you have a neighbor with a few pigs and you don't want the manure accumulating," Kelly said.

What's more, said Therien of the state board, the state departments of Ecology and Agriculture appear to have more specific authority over large livestock operations and their manure-management practices.

But Citizens for Sustainable Development of Monroe, Wash., in Snohomish County, which is battling an expansion by a dairy farm there, states that only the health board and its local jurisdictions have an explicit duty to protect the public against hazards posed by agricultural sewage.

The controversy started with a letter to the health board earlier this summer from the Washington Association of Conservation Districts, which asked that one part of the rule be amended.

John Larson, executive director, said the association's member district in Clark County found the provision requiring removal of manure once a week inconsistent with current science. He said the case grew out of a horse farm, not a large livestock operation.

The health board will convene a work group this fall to study the matter, Therien said.

* Leah Beth Ward can be reached at 509-577-7626 or lward@yakimaherald.com.