The Kansas Department of Health and Environment (KDHE) Bureau of Air and Radiation (BAR) licensed radium dial shops. According to BAR records, the former Karnish Instruments, Inc (KII) operated a facility repairing aircraft instruments from approximately 1965 to 1969. The former radium dial shop facility was located at 4711 East 31st Street South in Wichita, Kansas.
Radioluminescent paint—a mixture of a radionuclide, usually radium-226, and a phosphor, usually zinc sulfide—was developed in the early 1900s. The mixture was initially used on watch and clock faces and later adapted for use on instruments, most notably aircraft dials. As part of radium’s decay process it emits an alpha particle that can excite the phosphor which eventually releases a photon. The end results are dials that “glow” and can be read at night without light.
Exposure to high levels of radium results in an increased incidence of bone, liver, and breast cancer. Radium-226 is a hazardous substance, as defined by section 101(14) of the CERCLA, and is listed at 40 CFR part 302.4 as a radionuclide.
In an ongoing effort to evaluate these facilities, KDHE conducted field work in March 2007 to support a Unified Focus Assessment (UFA) Report issued in May 2007. Groundwater samples and soil samples at the Site were collected for the UFA. Analysis included radium-226; the eight Resource Conservation and Recovery Act (RCRA) metals, mercury, and volatile organic compounds (VOCs). The UFA identified several areas that had elevated radium concentrations exceeding the standard established at 40 CFR § 192.12 for a cleanup level not to exceed background plus five pCi/g; however, the UFA did not identify or find any areas that contained buried waste, septic tanks, containers, or a leachate field.
On April 21, 2009, KDHE referred this site to the EPA for a response action. The EPA is closely coordinating site activities with KDHE and the Sedgwick County Health Department. The Sedgwick County Health Department has volunteered to coordinate Site activities with the local governing bodies.
The objective of this removal action is to protect public health or welfare or the environment by responding to the release of hazardous substances and pollutants or contaminants into the environment as presented by soils contaminated with radium-226 at the Site. Contaminated soils that exceed 5 pico Curies per gram (pCi/g) plus background will be excavated and properly disposed of. The EPA conducted field activities for a Removal Site Evaluation (RSE) in June of 2009. Field screening with radiation detectors and radiation analysis of soil samples further defined the lateral, vertical, and aerial extent of contamination.
The Action Memorandum, signed August 23, 2010, outlines the scope of work covered by the removal action. The removal action was completed on October 7, 2010. The transportation, treatment, storage and disposal of the hazardous substances was done in accordance with all applicable local, state, and federal requirements.
At this time, no post removal Site control will be necessary.
