|The Century Instrument Corporation (CIC) site is located at 4440 South Southeast Boulevard (also 4444 and 4502) in Wichita, Kansas. At this location the facility operated as an aircraft instrument repair shop from 1980 to present. The facility possesses a Radioactive Materials License with the state of Kansas issued by KDHEs Bureau of Air and Radiation (BAR). Apparently post-1986 there was a release of radium-226 to soils on the site. In October 31, 1990 BAR filed a “Notice of Intent” regarding violations associated with the handling of radium dial instruments. An 8 by 20 foot area of soil situated near the northeast corner area of the westernmost building at CIC was determined by surface scanning to be radioactive. Remediation of the soil from this area was accomplished in 1999 to BARs satisfaction.
This Unified Focused Assessment (UFA) revealed evidence of the following Recognized Environmental Conditions (RECs) in connection with the property. Concentrations of trichloroethene (TCE) from the background and monitoring well #123 groundwater (GW) samples of 0.015 and 0.013 milligrams per liter (mg/L) respectively exceeded the primary residential Maximum Contaminant Level (MCL) for TCE of 0.005 mg/L. Elevated radiological survey results from a solitary storage semi-trailer and between the middle building and an adjacent storage container. The UFA also revealed evidence of the following Historical Recognized Environmental Conditions (HRECs) in connection with the property. Radioactive material licensing was issued for operations that included receiving possessing, and storing of aircraft instrument dials at this location. A documented release to the environment of Radium-226 above EPA/NCR-MOU screening standards to surficial soils on the property.
Two separate areas screened on the property had elevated readings for radiation. The highest surface reading recorded was 283 microroentgens per hour (µR/hr). This survey point was sampled as location #1s (located on the southside of the solitary semi-trailer situated southeast of the easternmost building). The other elevated location is situated between the center building and an unattached storage container (near the southern ends of the structures). Radiation was indicated with readings near three times the background rate increasing to a maximum of 42 µR/hr. Only trace amounts of radium-226 were detected from the soil samples analyzed from or near these two areas. The EPA/NRC MOU screening level for radium-226 in both residential and non-residential soils is 5 picoCuries per gram (pCi/g) plus background, which for this site is approximately 0.78 pCi/g.
There were no significant levels of radium or heavy metals potentially attributable to radium dial repair operations indicated in soil or GW at the CIC site.
The TCE REC identified in this UFA (the background - 0.015 mg/L and monitoring well #123 GW samples) are part of the GW monitoring network for the Boeing site, which is upgradient to the CIC site. Releases of TCE are well documented at the Boeing site. In 1987 Boeing signed a Consent Agreement with KDHE to investigate and remediate TCE (and associated degradation products). Since the highest TCE results at the CIC site were detected in the upgradient sample, the TCE releases are interpreted to be from the releases at the Boeing Site.
The UFA radiological survey results indicate elevated radiation levels between and along the west wall of a storage container and adjacent east wall of the middle building. Another area of elevated radiation levels was indicated around the solitary semi-trailer used for storage. The site will be referred to KDHE/BAR for further compliance of the radioactive materials license including decontamination and decommissioning of these areas.