The Agency for Toxic Substances and Disease Registry (ATSDR), a public health agency of the U.S. Department of Health and Human Services, is releasing the final version of the public health assessment (PHA) for the Tri-County Public Airport (TCPA) site.

ATSDR has reviewed available environmental data, exposure scenarios and community health concerns to determine whether exposure associated with the site can lead to adverse health effects. On the basis of this information, ATSDR concludes the following:

• One completed exposure pathway was identified. Persons were exposed to water from contaminated drinking water wells off-site by ingestion, inhalation and/or absorption.
• On the basis of a toxicological evaluation of contaminants present in wells, ATSDR believes that adverse noncancer and cancer health effects are unlikely near the TCPA site. However, concentrations of trichloroethylene (TCE) in some drinking water wells near the TCPA site are similar to concentrations of VOCs described in drinking water studies that have shown possible increased risk of birth defects and higher incidence of childhood leukemia due to ingestion of VOC-contaminated water during pregnancy.
• Three potential exposure pathways were identified; off-site surface water and springs, on-site drinking water wells, and on-site surface soil and sediment. ATSDR believes adverse noncancer and cancer effects are unlikely.
• ATSDR believes exposure to site-related contaminants via drinking water occurred in the past, but has no way to determine the length of exposure. Exposure to drinking water contaminants has been stopped by installing carbon filtration units at residences where exposures exceed the maximum contaminant level (MCL).

The proposed Tri-County Public Airport (TCPA) National Priorities List site is a former World War II Army Airfield. During its peak operating period, the airfield consisted of more than 300 buildings and housed approximately 2,000 personnel. The airfield had a wastewater treatment plant, a 200,000-gallon fuel storage tank, warehouse area, barracks, and a recreation area. The airfield was declared surplus in 1946. Most of the buildings and structures have been removed, but two hangars, a water tower, several water supply wells and a few small buildings remain.

From 1948 to present, the site has been leased to a number of companies. Operations at the site have included, but were not limited to, aircraft restoration, aircraft storage, and manufacturing of farm implements, black powder and roofing materials.

The nature and extent of environmental contamination at the site are still being determined. Presently, no one is now being exposed to site-related contaminants via drinking water at levels above the MCL. ATSDR saw no indication of trespassing at the site; however, the site is not fenced and areas of contaminated soil are still present. On-site workers potentially might be exposed to contaminated soils.

ATSDR makes the following recommendations about the site:

• Provide a more permanent solution for drinking water that meets Safe Drinking Water Act regulations to residences with contaminated well water in the vicinity of TCPA.
• Continue periodic monitoring of the groundwater plume to ensure that private drinking water wells currently outside the plume do not become contaminated by migration of the plume.
• Take appropriate preventive measures to mitigate exposure if these wells do become contaminated.
• Inform trespassers and present workers on the site that they should avoid unnecessary contact with site soils and sediment, especially near hangars 1 and 4.

The PHA is available for public review at the following repository:

Herington Public Library
102 S. Broadway
Herington, Kans. 67449

Members of the news media may request an interview with ATSDR staff by calling John Florence or Elaine McEachern in the ATSDR Office of Policy and External Affairs at (404) 498-0070.