Nearly 60 interested citizens attended a June 4 annual informational meeting to discuss potential building sites at the former Offutt Air Force Base Atlas “D” Missile Site 3.
Those in attendance included representatives from Iowa Department of Natural Resources and Harrison County.
The site has shown areas of contamination in soil and groundwater, and the U.S. Army Corps of Engineers is taking steps to mitigate that contamination.
Following the closure or sale of a former Department of Defense site, teams search for four types of contaminants – volatile organic compounds, semi-volatile organic compounds, petroleum byproducts, and polychlorinated biphenyls.
Locally, the remedial investigation has found volatile organic compounds in groundwater on some sites and polychlorinated biphenyls in four of nine areas where transformers were located, according to documents on file.
Because of the potential effect on human health with direct exposure to the contaminants, a Time Critical Removal Action is required.
The remediation process has already begun for many of the sites, some of which already have new structures built.
The USACE excavated 2,300 tons of soil, removed 100 tons of concrete, and thermally treated the site to remediate the PCB in the soil. They reported at the meeting that immediate exposures were eliminated, but more investigation is planned.
Additionally, 125 drinking water wells have been sampled within a three-mile radius of the original site. Trichloroethylene was found in several of those wells – some above the EPA maximum contaminant level.
A Granular Activated Carbon filter system was installed in the wells with high TCE amounts, and regular sampling will be done until those wells show no TCE for a full year.
Currently there are 16 existing residential drinking water treatment systems with 10 new installations planned. Each of these systems will undergo quarterly sampling.
The USACE announced at the meeting that any well at the site found with any TCE is eligible for a GAC system.
The final report is available at the Missouri Public Library.