PUBLIC HEALTH ASSESSMENT
MOUNTAIN HOME AIR FORCE BASE
MOUNTAIN HOME, ELMORE COUNTY, IDAHO
Based on an evaluation of available environmental information, ATSDR reached the following conclusions and assigned a public health hazard conclusion category.
- No public health hazards are associated with soil exposures at Mountain Home AFB because contamination was either (1) detected at levels that did not pose a public health hazard; (2) detected at depths below the ground's surface which are not accessible to the public; or (3) detected in areas where site access was restricted, unlikely, or infrequent.
- No public health hazards are associated with drinking water supplied by on-base wells because (1) contaminants were detected at levels that do not pose a public health hazard and (2) drinking water on base is monitored regularly in compliance with federal and state regulations. Trihalomethanes (bromoform, bromodichloromethane, and chlorodibromomethane) and TCE were detected in the base production wells at levels above ATSDR comparison values but below EPA MCLs. Using conservative estimates of potential exposure doses, ATSDR determined that exposure to the base water supply by on-site workers and residents is not expected to pose a public health hazard.
- No public health hazards are associated with the use of off-site drinking water wells because contaminants detected in a private off-base well were at levels which do not pose a public health hazard.
- No public health hazards are associated with surface water and sediment exposures at Mountain Home AFB because (1) limited surface water exists on the base and (2) the surface water is relatively inaccessible to the general public.
Based on a review of available information on contamination of soil, groundwater, and surface
water and sediment, ATSDR concludes that Mountain Home AFB should be assigned to the No
Apparent Public Health Hazard category.
The public health action plan (PHAP) for Mountain Home AFB contains a description of actions taken and those to be taken at and in the vicinity of the base subsequent to the completion of this public health assessment (PHA). The purpose of the PHAP is to ensure that this PHA not only identifies potential and ongoing public health hazards but also provides a plan of action designed to mitigate and prevent adverse human health effects resulting from exposure to hazardous substances in the environment. The following actions at Mountain Home AFB have been completed, are ongoing, or are planned:
- The Air Force completed investigations at the 33 IRP sites to identify potentially contaminated areas. Soil investigation and cleanup are completed at these areas (Table 2).
- The underground storage tanks were removed from the Military Gas Station (ST-32) in 1992.
- Property deeds were amended to impose restrictions and to include contamination issues. Site conditions will be re-evaluated if a change in land use is proposed in the future.
- The building at the Entomology ShopYard (SD-12) was demolished and the underground storage tank was removed in 1987. The site is currently paved with asphalt and used as a parking lot.
- The four underground storage tanks at the Petroleum, Oil, and Lubricants; Gasoline Tank Site (ST-13) were removed in 1988. The site was backfilled with clean soil and covered with a clay cap.
- In 1992, the radioactive materials were removed from the Radioactive Material Burial Site (RW-14) and disposed as low-level radioactive waste.
- The burn pit at the Munitions Disposal Area (OT-16) was cleaned out and backfilled with new soil. The furnace at the site was dismantled in 1992.
- The abandoned underground storage tanks at Titan Missile Maintenance (ST-22) area have been filled with sand.
- The drain trough and oil sump at the Auto Hobby Shop/Munitions Trailer (SD-24) were capped with concrete in the mid-1980s.
- A covered shed was built at the Drum Accumulation Pad (SS-26) in 1990 to house drums containing solvents and wastes.
- The drainage ditch at the Wash Rack (SD-27) was filled in and replaced with an oil/water separator and piping to remove wastewater discharges in 1993.
- Contaminated soils at the Former Wash Water Accumulation Pit (SS-28) were removed and disposed when the site was closed in 1987.
- In 1992, the underground storage tanks and 800 cubic yards of contaminated soil were removed from the Base Exchange Gas Station Site (ST-31) and replaced with clean backfill.
- A fuel hydrant and surrounding soils were removed from the Fuel Hydrant No. 9 System Leak Area (ST-34) in 1991.
- Soil was excavated from a 50 by 3.5 foot area around the spill site at the Jet Fuel Pipeline Leak (ST-35) and brought to an on-base land farm for remediation.
- The oil/water separators located throughout the base (AOC-8) were decommissioned and the associated underground storage tanks were removed in 1997.
- The Air Force will continue to test the base water supply to ensure compliance with state and federal regulations.
- The base-wide groundwater is subject to long-term monitoring and the status of the groundwater at Mountain Home AFB will be re-evaluated every 5 years.
Federal Facilities Assessment Branch
Division of Health Assessment and Consultation
Gary Campbell, Ph.D
Environmental Health Scientist
Federal Facilities Assessment Branch
Division of Health Assessment and Consultation
REFERENCESAir Force - See Department of the Air Force.
ATSDR. 1989. Agency for Toxic Substances and Disease Registry. Toxicological Profile for
Bromodichloromethane. December 1989.
ATSDR. 1990. Agency for Toxic Substances and Disease Registry. Toxicological Profile for
Bromoform and Chlorodibromomethane. TP-90-05. December 1990.
ATSDR. 1991. Agency for Toxic Substances and Disease Registry. Site scoping notes for
Mountain Home AFB, Mountain Home, Idaho.
ATSDR. 1997. Agency for Toxic Substances and Disease Registry. Toxicological Profile for
Trichloroethylene (update). September 1997.
Bigsby, P.R. 1995. Groundwater Geology of Mountain Home Air Force Base, draft prepared for
U.S. Air Force, Mountain Home AFB. April 1995.
Department of the Air Force. 1996. Consultative Letter - Nitrate Study, Mountain Home AFB
from Capt. Fronapfel, Brooks AFB, Texas to Capt. Perry, Mountain Home AFB, Idaho. 1996.
Department of the Air Force. 1997a. Personal correspondence between Lieutenant Doug Ebert,
Mountain Home AFB and Mark Weber, ATSDR. December 1997.
Department of the Air Force. 1997b. Management Action Plan, Mountain Home Air Force Base,
Idaho. December 1997.
Department of the Air Force. 1997c. Mountain Home Air Force Base Community Relations Plan.
Department of the Air Force. 1998. Personal correspondence between Lieutenant Doug Ebert,
Mountain Home AFB and Audrey Wagenaar, Eastern Research Group. March 1998.
EA Engineering. 1993. Identification of Data Gaps, Sampling and Analysis Plan, Sampling and
Analysis Cost Estimates, prepared for Armstrong Laboratory-Brooks Air Force Base, Texas,
Headquarters-Air Combat Command, Bioenvironmental Engineering, Langley Air Force Base,
Virginia and Mountain Home Air Force Base, Idaho. September 1993.
Radian Corporation. 1990. Final Remedial Investigation Report - Mountain Home Air Force
Base, Idaho. Volumes 1-5. March 1990.
Resources Conservation Company. 1989. Installation Restoration Program - Baseline
Endangerment Assessment, Site 8, Mountain Home Air Force Base, Idaho. February 1989.
U.S. Bureau of the Census. 1991. Census of Population and Housing. 1990.
Woodward-Clyde. 1991. IRP Remedial Investigation/Baseline Risk Assessment Operable Unit 4,
Mountain Home AFB, Idaho. December 1991.
Woodward-Clyde. 1992. Record of Decision for Mountain Home AFB, Site 8, Fire Training Area
8, Operable Unit 4. June 1992.
Woodward-Clyde. 1993. Installation Restoration Program - Mountain Home Air Force Base,
Operable Unit No.3 - Remedial Investigation/Feasibility Study. Technical Memorandum - General
Groundwater Quality. June 1993.
Woodward-Clyde. 1994. Installation Restoration Program - Mountain Home AFB, 366th Wing,
Draft Final, Operable Unit 3 Remedial Investigation - Base wide Groundwater and Ecological
Risk Assessment, prepared for the U.S. Department of the Army Corps of Engineers. October
Woodward-Clyde. 1995. Draft Record of Decision for Mountain Home AFB Operable Units Nos.
1,3,5, and 6. July 1995.
Woodward-Clyde. 1996. Installation Restoration Program - Mountain Home Air Force Base,
366th Wing, Final Post-ROD Groundwater Monitoring Plan, prepared for the U.S. Department of
the Army Corps of Engineers. May 1996.