Posted: Thursday, December 27, 2012 12:00 PM
Dan Wheat/Capital Press
Raul Fernandez washes the deck around a post-digester separator at George DeRuyter and Sons Dairy. The dairy is the only one in Eastern Washington with an anaerobic digester converting biogas from manure into electricity. That will be changed to make renewable natural gas.
EPA study assumed leakage rate, 'filled with considerable errors'
By DAN WHEAT
SUNNYSIDE, WASH. -- An EPA report saying dairies near Sunnyside are a likely source of nitrate pollution in groundwater and drinking water in the Lower Yakima Valley is "filled with considerable errors" and can't be "scientifically defended to derive at the stated conclusions," according to the Natural Resources Conservation Service.
The EPA study, released Sept. 27, "does not accurately represent the likely discharge rate occurring from dairy waste storage discharge ponds identified in the report," the NRCS said in a Dec. 7 letter to the Environmental Protection Agency.
That's because the EPA used limited site information and assumed values for computing specific discharge, resulting in "findings that are erroneous and unreliable," NRCS state staff wrote.
Tom Eaton, director of EPA's Washington Operations Office in Olympia, agreed his agency assumed leakage rates because the EPA was unable to get design and construction information about the lagoons from the dairies.
"If there are errors in our report we will correct those errors," Eaton said.
The agency has drilled new monitoring wells and should have new data from them in another month that will provide a clearer picture of the problem, he said.
EPA is reviewing 38 letters and emails it received from a public comment period on its report and is continuing to negotiate with the dairies for them to provide clean drinking water to down gradient homes, address sources of nitrates and monitor them, Eaton said.
The EPA supports plans of George DeRuyter & Sons Dairy and Cow Palace Dairy to expand and improve a manure digester to lessen nitrates and produce natural gas, Eaton said.
"That can be a good part of the long-term solution," he said.
The NRCS recommends EPA get accurate estimates to compute the discharge, taking into account whether ponds are lined.
The NRCS recommends greater consideration be given other nitrate sources -- including organic and synthetic fertilizer -- that have more potential to impact groundwater than the ponds.
The NRCS letter, signed by State Resource Conservationist Bonda Habets and State Conservation Engineer Lawrence Johnson, contained equally critical comments from NRCS specialists for nutrient management and agricultural waste management. They recommended the EPA report be retracted and proper data collection begin in earnest.
"It appears the high levels of nitrate found in drinking water wells in the Yakima Valley are coming from multiple sources. More information is needed to help focus attention on site and management issues contributing to pollutants," the NRCS stated.
National experts hired by the Washington Dairy Products Commission and the Washington State Dairy Federation also were critical of EPA methods and findings.
One of them noted manure has sealing characteristics that become more effective over the life of earthen lagoons.
EPA's push for consent orders with four dairy families is inappropriate, said Glorieta Geoscience Inc., Santa Fe, N.M., hired by the state Dairy Products Commission.
"EPA did not produce enforcement-quality data from this study," Glorieta Geoscience said.
The EPA report has created confusion and distrust among affected communities and parties, Yakima County Commission Chairman Rand Elliott said in a letter to the EPA.