The assessment was conducted under the authority of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 and the Superfund Amendments and Reauthorization Act (SARA) of 1986.  Karnish is a former radium dial aircraft instrument repair shop.  Karnish operated on the property from as early as 1965 to as late as 1969 under the name Karnish Instruments, Inc.  Tech-Aire Instruments, Inc. operated on the site from as early as 1982 through 1989 (Kansas Department of Health and Environment [KDHE] 2007).  An investigation at the site by KDHE, reported in December 2006, identified radium-226 impacted soil on the site (KDHE 2007).

1.1.2.1 Location
The former Karnish Instruments site is located at 4711 East 31^st Street South in Wichita, Kansas.  The site is in the northeast quarter of Section 11, Township 28 South, Range 1 East, at the following geographic coordinates:  37.634700 degrees north latitude and 97.281390 degrees west longitude.  The site property occupies approximately 2/3 acre.  The property is in a commercial area in the southeast part of Wichita, Kansas.  A single-story building located on the western portion of the property covers approximately 4,900 square feet of the property.  The on-site building is currently occupied by EBY Construction Company, Inc. (EBY).

1.1.2.2 Description of Threat
The primary contaminant of concern at this Site is Radium-226.  EPA and KDHE have documented Radium-226 concentrations in soil exceeding 5 pCi/g plus background (up to 1,230 pCi/g).  Radium-226 is a hazardous substance as defined by section 101(14) of CERCLA, and is listed at 40 CFR § 302.4 as radionuclides.

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.  Radium has 25 known isotopes, four of which occur in nature, with Radium-226, and to a lesser extent, Radium-228 being the most common.  Radium-226 has the longest half-life at 1,602 years.  Radium is a decay product of uranium and consequently is associated with uranium ores.   Radium decays by emitting alpha and beta particles and gamma rays.  Radium initially decays into radon, a heavy gas, which itself decays into other radioactive solids including polonium, bismuth, lead, and thallium.  Radium in soils does not biodegrade.

EBY workers and nearby merchants at and near the former Site property or passersby may be exposed via routes of inhalation or dermal contact to loose soils in the parking areas.  The greatest risk to humans from radium is through ingestion of food and water documented by the Agency for Toxic Substances and Disease Registry’s Toxicological Profile for Uranium, Section 5.5 (December 1990).  EBY construction personnel at the former Site are exposed by parking and walking through the radium-contaminated soils on a daily basis.  Exposure to high levels of radium results in an increased incidence of bone, liver, and breast cancer.  Radium, like calcium, is retained in bone tissue; bone cancer is the greatest risk from radium exposure.  Death and decreased longevity have been reported as a result of long-term exposure.  Radium has also been shown to affect the blood (anemia), eyes (cataracts), and teeth (increased broken teeth and cavities).  Emitted ionizing radiation from the decay of radium and its daughters can lead to skin damage, hair loss, birth defects, general illness, and cancer.  

KDHE conducted field work in March 2007 to support a Unified Focus Assessment (UFA) report issued in May 2007.  Three groundwater samples and 20 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.  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 5 pCi/g (the cleanup level has been established at 16.5 pCi/g at a depth of six inches up to 1,230 pCi/g of Radium-226 at a depth of two feet); however, the UFA did not identify or find any areas that contained buried waste, septic tanks, containers, or a leachate field.

The EPA conducted field activities for a Removal Site Evaluation (RSE) in June 2009.  Field screening with radiation detectors and radiation analysis of soil samples further defined the lateral, vertical and aerial extent of contamination.  Sample results of 239 pCi/g for radium-226 occurred at a depth of 0 - 2 feet and 10.8 pCi/g occurred at a depth of three to four feet.

Beckie Himes, PIO

Office of Public Affairs

U.S. EPA Region 7

901 N. 5^th Street

Kansas City, KS 66101

Phone: 913-551-7253 or

Toll Free: 1-800-223-0425

himes.beckie@epa.gov

September 2010 - The U.S. Environmental Protection Agency (EPA) Region 7 will conduct a Removal Action (RA) at the Karnish Instruments, Inc. site at 4711 E. 31st Street South in Wichita, Kansas.  The Kansas Department of Health and Environment conducted a Unified Focused Assessment at the site and requested EPA to perform the RA.