Other chemicals also showing up in well tests

BURLEY — Cassia County residents in rural areas, especially people with older wells in the Springdale area, should have their water tested for contaminants.

Idaho Department of Environmental Quality spokesman John Boker said during a Cassia County Commission meeting Monday the agency recently tested 13 domestic wells in the Springdale area between Burley and Declo — along with two surface water sites and two drain sites — three times to capture seasonal variations in the water. The tests included wells that went as deep as 200 feet.

“It’s a hot spot within a hot spot,” Boker said. “The county is a nitrate priority area and that trend is increasing to some extent.”

Along with DEQ, the Idaho State Department of Agriculture, Idaho Department of Water Resources and U.S. Geological Survey Water Resources combined efforts for the study that examined the level of contaminants in more than a dozen Springdale wells.

Boker said not only are there high levels of nitrates, which have been shown to harm pregnant women and babies, but officials are also finding both animal and human pharmaceuticals and personal-care products in the water. Caffeine, human anti-seizure medicine and steroids were detected in some of the samples. Eight of 10 wells showed the presence of antimicrobials used in veterinary practices.

An analysis of the study states although the compounds were detected at low concentrations the frequency and distribution represents a real occurrence of the chemicals in groundwater.

The possible sources of the chemicals were identified as confined-animal feeding operations, septic tanks and legume crop residues, according to the study.

Nitrate concentrations in the area commonly exceed both Idaho and federal drinking water standards of 10 milligrams per liter.

“All but one test came back over 10 mg/L and a lot of them were in the teens,” said Carolyn Firth, a water quality resource conservationist with the Idaho Soil Conservation Commission.

“A reverse osmosis filter is the only filter that will take out nitrates,” said Firth.

Firth said the Snake River aquifer tends to run fairly swiftly through many parts of southern Idaho but is somewhat stagnant underneath Springdale and the Cassia County in general.

“It flows rapidly until it gets to Springdale and then it just sits there,” Firth said.

Boker said new wells should be constructed with the proper sealants to ensure contaminants do not leech into drinking water supply. But many of the wells in the county were built a long time ago and to different standards.

Boker said ultimately the problem is not going to get any better unless the county addresses the source, which could mean regulatory options.

“What disturbs me is that most of it is a preventable thing,” Boker said. “It comes down to economics and agriculture.”

Cassia County Commissioner Paul Christensen said it takes a long time to reduce nitrate levels in an area and the best advice would be for residents in rural areas who have older wells to get them regularly tested.

Cassia County Commissioner Dennis Crane said the commissioners support efforts to educate the public about the problem.

Laurie Welch may be reached at lwelch@magicvalley.com or 208-677-8767.