Cerro Gordo County study to measure arsenic in private wells

Image: The Des Moines Lobe was created more than 12,000 years ago by the last glacier to enter Iowa, forming ridges and knobby hills in the central part of the state. It is also known to have left deposits of arsenic. The State Hygienic Lab at the University of Iowa is part of a study to measure the presence of arsenic in the north central county of Cerro Gordo.

Other partners include Doug Schnoebelen, in the University of Iowa Department of Civil and Environmental Engineering; the Iowa Geological Survey; the UI Center for Health Effects of Environmental Contamination (CHEEC); the Iowa Department of Natural Resources; and Shawver Well Company.

“Cerro Gordo is in the Des Moines Lobe, which is known to have geological deposits of arsenic,” said Michael Wichman, associate director of Environmental Health Programs. The Des Moines Lobe is a geological area in central Iowa formed by a glacier 12,000 years ago.

Wichman, Lorelei Kurimski, program consultant, and Don Simmons, environmental program manager, are coordinating the State Hygienic Lab’s portion of the project.

The Hygienic Laboratory has partnered in previous arsenic studies, including a three-year statewide CHEEC study of 475 private wells in 91 of Iowa’s 99 counties in 2008. That project determined that groundwater in Cerro Gordo County has persistent arsenic at levels above 10 parts per billion, which is the allowable level for public water supplies. In a follow-up study by Cerro Gordo County Department of Health, arsenic was detected in 70 percent of the samples; 38 percent measured above 10 parts per billion.

“What we hope to come out of this is a model to estimate the risk of arsenic exposure in groundwater,” Wichman said. “If that model holds true, it could be applied nationwide. So, it is a worthwhile project.”

At least 50 private wells are expected to be tested two times each over a three-year period.

In addition to water, the laboratory will test soil, sand and rock from core samples collected when new wells are drilled. Cerro Gordo County Board of Health enacted an ordinance in 2007 requiring arsenic testing for new and reconstructed wells in the county.

Arsenic is a naturally occurring element that, if ingested at high levels, can cause potentially serious health problems ranging from skin warts to cancer.

Under the Safe Drinking Water Act, public water supply providers are required to test for arsenic in water. There is no such federal requirement for private wells.

The Hygienic Laboratory is the state of Iowa’s environmental and public health laboratory, with facilities located at the University of Iowa’s Research Park campus in Iowa City, in the Des Moines suburb of Ankeny and at the Lakeside Lab in northwestern Iowa. For more information about the laboratory and its programs and services, visit http://www.uhl.uiowa.edu.

STORY SOURCE: Hygienic Laboratory at the University of Iowa, 102 Oakdale Campus, H101 OH, Iowa City, Iowa 52242-5002

MEDIA CONTACT: Pat Blake, 319-335-4177, [email protected]