PUBLIC HEALTH ASSESSMENT
SHARPE ARMY DEPOT
(a.k.a. DEFENSE DISTRIBUTION DEPOT SAN JOAQUIN, CALIFORNIA--SHARPE)
LATHROP, SAN JOAQUIN COUNTY, CALIFORNIA
On the basis of ATSDR's evaluation of environmental information collected during the site characterization and remedial process, ATSDR reached the following conclusions and assigned public health conclusion categories.
ATSDR determined that Sharpe poses no apparent public health hazard.
- Groundwater under the site is contaminated with VOCs, primarily TCE and PCE, related to
past equipment maintenance activities. Some VOCs have migrated with the groundwater to
off-site areas. Sharpe monitors on-site potable wells and 30 to 40 private wells near the site,
and the city of Lathrop regularly monitors the public water supply. Only three private wells
were found to contain VOCs at levels marginally above the ATSDR comparison value. The
detected VOCs levels are not expected to pose a human health hazard to users of the private
wells. No other off-site public or potable wells appear to contain site-related VOCs or
pesticides at levels above ATSDR's comparison values. Future exposure should be reduced
further because Sharpe has an active groundwater treatment program to capture and eliminate
Arsenic was detected in on-site potable wells at levels above the ATSDR comparison value, but below the EPA and CA MCL. ATSDR determined that users of the on-site potable wells (i.e., on-site workers and residents) are not expected to develop arsenic-related health effects. The source of the arsenic has not been determined.
- Elevated levels of lead, chromium, and pesticides contaminate on-site surface soils in localized industrial portions of the site as a result of past disposal, storage, and use practices. A fence and regular security patrols limit public access to these areas of surface soil contamination. The pesticide-contaminated soil was removed in 1995, and remediation actions have been proposed for the lead- and chromium-contaminated surface soil. Workers and personnel having access to the area are not expected to contact the isolated areas that have elevated contaminant concentrations with great frequency or for any significant length of time. Only low lead levels below those associated with public health hazards were found in the on-site residential area surface soil.
- People living in on-site residences are not likely to be exposed to elevated indoor TCE concentrations resulting from soil gas infiltration into the buildings. TCE concentrations in soil gas within the residential area were consistently low, and these low TCE levels are not expected to migrate and accumulate in the indoor residential air environment at levels associated with human health hazards. Furthermore, VOC plumes that may contribute to soil gas concentrations are not moving toward the residential area.
- People are not indirectly exposed to site-related contaminants at levels associated with public health hazards when they consume locally grown crops or beef. ATSDR evaluated available data and reviewed scientific literature and determined that crops and livestock would not likely accumulate the arsenic from off-site surface soil in quantities sufficient to cause adverse health effects.
The Comprehensive Environmental Response, Compensation, and Liability Act of 1980 , as amended, requires ATSDR to perform public health actions needed at hazardous waste sites. No public health actions are currently needed because there is no exposures at Sharpe at levels that pose a public health hazard; however, ATSDR recommends the following actions to further characterize potential public health hazards at this site.
- ATSDR recommends continued monitoring of the private wells located near the 7/8 plume to determine whether contaminants have migrated to off-site private wells at levels above the MCL. If contaminants are detected at levels above the MCL, appropriate measures should be taken to prevent the use of the contaminated wells (e.g., alternative water sources).
- ATSDR recommends that Sharpe continue to monitor for arsenic in the on-site potable wells. If results consistently show levels near the MCL, then Sharpe should consider taking measures to reduce the arsenic concentrations. If continued off-site monitoring indicates that arsenic is present in the deep aquifer where wells most likely draw water, ATSDR recommends that this information be made available to private well users in those areas.
- ATSDR recommends that if future land use changes from industrial use, clean up to meet residential standards should be considered.
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
ATSDR. 1989. Preliminary health assessment for Sharpe Army Depot, Lathrop, San Joaquin, California. CERCLIS No. CA8210020832. April 1989.
ATSDR. 1991. Trip Report. Sharpe Army Depot, Lathrop, San Joaquin, California. May 1 and 2, 1991.
ATSDR. 1993a. Toxicological profile for arsenic. Atlanta: US Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry. TP-92/02.
ATSDR. 1993b. Toxicological profile for tetrachloroethylene. Atlanta: US Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry. TP-92/18.
ATSDR. 1996a. Population demographics for Sharpe Army Depot, Lathrop, San Joaquin, California, 1996.
ATSDR. 1996b. Health consultation for Sunflower Army Ammunition Plant (SFAAP), DeSoto, Kansas. Atlanta: US Department of Health and Human Services, Public Health Service.
Centers for Disease Control and Prevention (CDC). 1991. Preventing lead poisoning in young children. Atlanta: US Department of Health and Human Services, Public Health Service.
California Regional Water Quality Control Board (CRWQCB). 1997. Letter from Cori Condon, CRWQCB, to Emilio Gonzalez, ATSDR, regarding VOCs in private wells. September 16, 1997.
Department of Defense (DOD). 1996. Fax sent to Eastern Research Group, Inc. from John Guzman, Installation Restoration Program Manager. Defense Logistics Agency, Defense Distribution Region West. September 1996.
DOD. 1997a. Fax sent to Eastern Research Group, Inc. from John Guzman, Installation Restoration Program Manager. Defense Logistics Agency, Defense Distribution Region West. RE: Private Well Quarterly Monitoring Data. June 1997.
DOD. 1997b. Personal communication between Eastern Research Group, Inc. and John Guzman, Installation Restoration Program Manager. Department of Defense, Defense Logistics Agency, Defense Distribution Region West.
Environmental Protection Agency (EPA). 1989. Development of risk assessment methodology for land application and distribution and marketing of municipal sludge. Washington, DC: US Environmental Protection Agency, Office of Health and Environmental Assessment. EPA 600/6-89/001.
EPA. 1992. Air/Superfund national technical guidance study series: assessing potential indoor air impacts for Superfund sites. Research Triangle Park, NC: Environmental Protection Agency. EPA-451/R-92-002.
Environmental Science & Engineering, Inc. (ESE). 1991a. Remedial investigation/feasibility study (groundwater feasibility study report) volume 1. Environmental Science & Engineering, Inc. November 20, 1991.
ESE. 1991b. Remedial investigation/feasibility study (risk assessment report) volume 1. Environmental Science & Engineering, Inc. November 26, 1991.
ESE. 1993. Remedial investigation/feasibility study record of decision. Operable Unit 1. Environmental Science & Engineering, Inc. January 7, 1993.
ESE. 1994a. Final remedial investigation study at Sharpe site soils risk assessment report. Volume 1. Environmental Science & Engineering, Inc. December 16, 1994.
ESE. 1994b. Final remedial investigation study at Sharpe site soils feasibility study report. Volume 2. Environmental Science & Engineering, Inc. December 16, 1994.
ESE. 1994c. Final remedial investigation study at Sharpe site soils risk assessment report. Volume 1. Appendix K. Environmental Science & Engineering, Inc. December 16, 1994.
ESE. 1996. Final record of decision base wide remedy for Sharpe site. Environmental Science & Engineering, Inc. Gainesville, FL. February 1996.
Gebhardt, G. 1996. Personal communication between Eastern Research Group, Inc. and Glenn Gebhardt, Lathrop, CA, Public Works Department. September 1996.
Lathrop Public Works Department (LPWD). 1996. Lathrop Public Works Department annual drinking water quality report.
Radian Corporation (Radian). 1996. Defensive Logistics Agency (DLA) Defense Distribution Region West (DDRW) Lathrop, California. DDRW-Sharpe FFA annual progress report. January 1996-December 1996. Draft.
Radian. 1997a. Defense Distribution Region West (DDRW) Sharpe, California. Operable Unit 2 pre-design technical summary. Prepared for US Army Corps of Engineers, Huntsville AL. January 1997.
Radian. 1997b. Defense Distribution Region West (DDRW) Sharpe, California. Addendum to the Operable Unit 2 pre-design technical summary. Prepared for US Army Corps of Engineers, Huntsville AL. September 1997.
US Army Corps of Engineers (US ACE). 1996. Defense Distribution Region West (DDRW), Sharpe, California. Well monitoring program quarterly monitoring report: second quarter 1996 sampling round. July 1996. Huntsville, AL: Engineering Support Center.
US Army Center for Health Promotion and Preventive Medicine (US ACHPPM). 1994. Draft Field Study No. 75-23-YS50-94, Health risk assessment of consuming deer from Aberdeen Proving Ground, Maryland. US Army Center for Health Promotion and Preventive Medicine. (October).
US Army Environmental Hygiene Agency (US AEHA). 1994. Draft final risk assessment from consumption of deer muscle and liver from Joliet Army Ammunition Plant. US Army Environmental Hygiene Agency. January 14, 1994.
WEST. 1996. Analytical reports for SHARPE annual potable water supply monitoring. WEST Laboratory, Davis, California. (June).