Drinking Water Tests Negative for Mercury

PULLMAN, Wash. — Washington State University environmental health officials report independent tests found no detection of mercury in water samples taken late last week from the water system near Terre View Extension and Round Top Reservoir roads.

David R. Clark, assistant director of WSU Environmental Health and Safety, said last Thursday that City of Pullman employees noticed mercury on the ends of abandoned WSU drinking water lines along the Ring Road project on the campus’ northeast end. EH&S staff cleaned up the site, including exposed pipes and contaminated soil. The WSU unit also collected drinking water samples from the closest water taps and delivered them to a local laboratory.

On Friday, the labs informed EH&S that there was no mercury detected in the water samples.

“We know that the mercury source is not from the groundwater or the WSU wells, since they are sampled on a routine basis. Mercury has never been found in the groundwater,” said Gene S. Patterson, public health manager for EH&S.

Elemental mercury is not soluble in water, so mercury found in distribution lines would not contaminate the drinking water. “Nevertheless, WSU did sample the water at the closest locations from the mercury location possible. No mercury was detected in the samples,” Patterson said.

Clark said the Department of Health, the Department of Ecology and the Whitman County Department of Health were notified of the mercury discovery and sample results. The City of Pullman received a copy of the laboratory results.

State and county health department officials indicated no additional sampling was necessary at this time.

This part of the Ring Road project includes redesign of portions of the WSU water system and will replace some 500 feet of pipe. The pipe in question had been removed from the line and placed along the roadside by project subcontractors. The older pipe will be removed from the area and examined in mid-September when that portion of the road is regraded.