HEALTH CONSULTATION

Kelly Air Force Base
San Antonio, Bexar County, Texas

CERCLIS No. TX2571724333


October 5, 2000

Prepared by:

U. S. Department of Health and Human Services
Public Health Service

Federal Facilities Assessment Branch
Division of Health Assessment and Consultation
Agency for Toxic Substances and Disease Registry
Atlanta, GA 30333


BACKGROUND AND STATEMENT OF ISSUES

The Agency for Toxic Substances and Disease Registry (ATSDR) received a request from the Environmental Protection Agency, Region VI in Dallas, Texas to review radiological sampling information for Kelly Air Force Base (KAFB). The data pertained to the radiological contamination within Building 324 on the base. This review, similar to a previous review by ATSDR (1) was to determine if radiological contamination levels were within acceptable limits for release of the building to the public or if additional actions would be needed prior to its release. The information supplied to ATSDR was prepared by a contracting agency that performed the radiological survey in the building for the Air Force (2) . The historical review of building operations suggests that radium was used during instrument dial maintenance. The building has now been structurally modified. From the documentation supplied, the modifications include the installation of a tile floor that effectively shields the potential radiological contamination from the detection instrumentation. Therefore, characterization of the reported contamination is difficult.

 

DISCUSSION

ATSDR has reviewed the report and offers the following comments. ATSDR believes the report to be insufficient to adequately determine if the area in question is contaminated above action levels established by the contractor or above surface contamination levels established by the Nuclear Regulatory Commission and as previously discussed [1]. Therefore, it is prudent to keep the area under restricted access and controls. The area thought to be contaminated should be evaluated for the presence of elevated levels of radon-222 as this is a decay product of radium 226 used in the paint. ATSDR agrees with the report that if contamination is present, the chance for migration is low at this time. Our reasoning is that the adhesive used in the installation of the tiles can also serve to fix the contamination in place effectively reducing the chance for contaminant migration. However, if remedial actions are to take place in this building, the remedial actions may increase the likelihood for exposure as large amounts of dust could be generated.

The inability to effectively monitor or to characterize the floor contamination is somewhat troubling as other facilities within KAFB have shown significant levels of radium contamination [1]. ATSDR believes this issue could be partially resolved by testing the monitoring equipment by using a radium source such as one used to calibrate the equipment and placing tile material between the detector and the radium source. These results could be used to better estimate the degree of contamination.


CONCLUSIONS AND RECOMMENDATIONS

Because the amount of information present to determine if Building 324 is radiologically contaminated is insufficient, ATSDR believes the facility should be considered contaminated and the following steps should be considered.

  • Perform radon monitoring in the areas thought to be radiologically contaminated.
  • Obtain a sample of tile from the floor area to test for the presence of contamination.
  • Maintain access control in the area.

    • Paul A. Charp, Ph.D.
    Senior Health Physicist

    REFERENCES

    1. Agency for Toxic Substances and Disease Registry (2000). Public Health Consultation for Kelly Air Force Base, San Antonio, Bexar County, Texas. August 23, 2000.

    2. Aguirre Engineers, Inc. (1999). Radiological consultative letter from Thomas J. O'Dou. Subject: Consultative letter, AEI-Kelly-324, Status survey of Building 324, former radium paint shop. November 10, 1999.