PUBLIC HEALTH ASSESSMENT
OGDEN DEFENSE DEPOT
OGDEN, WEBER COUNTY, UTAH
ATSDR concluded that DDOU poses no apparent public health hazard. The available data do not indicate that people are being exposed to contamination. Community-specific health outcome data were not reviewed because there were no completed exposure pathways identified, and no specific community health concerns were identified for which health outcome databases are available.
1. Groundwater on post is contaminated with VOCs, BNAEs, pesticides, and metals. Groundwater off post (beyond the DDOU boundaries) is not currently contaminated at levels above MCLs, although the plume could migrate. Cis-1,2-DCE shallow groundwater contamination is centered near OUs 1, 2, and 4. TCE contamination is centered around OUs 2 and 4. Vinyl chloride contamination is centered near OUs 1 and 4. Groundwater, which is used as drinking water downgradient from the contaminant plume, is a future potential pathway, particularly for residents who live adjacent to the DDOU western boundary. The state engineers' office has identified 11 families drawing water from the shallow aquifer less than one mile downgradient from the plumes. DDOU has conducted an off-post survey of well usage, and determined that seven private wells west of the depot boundary are in use. DDOU will sample those wells and determine their use if requested by the residents. The groundwater contamination plume in the upper aquifer has been defined, and DDOU will begin remediating the shallow aquifer once the treatment system design is complete. Some contaminants exceeding comparison values are not listed for inclusion in future analyses.
2. Water samples have been field-filtered before analysis for metals. A 1986 unfiltered metals analysis showed concentrations more than four times the drinking water standard. EPA and the state agree with DDOU that the source of metals contamination in groundwater is not attributed to DDOU (11)(12). Soils in the region contain naturally occurring metals at high concentrations that may leach into the groundwater. EPA and the state agree that the deep aquifer has not yet been contaminated by DDOU sources. EPA is requesting routine sampling of existing deep wells (10). If routine sampling shows that the deep aquifer is not contaminated and DDOU implements measures to treat the shallow aquifer, then it is likely the deep groundwater would not represent a pathway of exposure.
3. A potential pathway may be associated with Burial Site 1 and other suspected burial areas on the grounds of the Ogden Nature Center (formerly part of DDOU). Drum remnants are visible in several areas at the nature center, but in areas that are infrequently used. An electromagnetometer survey of Burial Site 1 showed subsurface anomalies, possibly indicating additional burial areas or other ground disturbances. Several areas have been excavated to create ponds. None of the ponds were constructed in known or suspected disposal areas. One test pit (TP-1) and one borehole sample (SB-27) were collected from the Ogden Nature Center near Burial Site 1. Undisturbed soil was encountered in the test pit, indicating that the excavation was not in the burial site. The sample was analyzed for BNAEs, pesticides/PCBs, and metals. No soil contamination was detected to a sampling depth of 6.5 feet. If contamination is encountered, people who could be exposed to contaminants through incidental ingestion of and dermal contact with surface soil. The potentially exposed population includes children, other visitors to the nature center, and workers. Those incidental exposures would not be sufficient to cause adverse health effects. The partially exposed metallic debris could be a physical hazard.
5. Waste solvents, oils, and other debris were burned at DDOU from the 1940s to the mid-1960s. Particulates from the burning could have potentially been carried downwind to a housing area some 1,500 feet west-northwest. On-site workers were also potentially exposed. Air was not sampled during the burning period, however, based on the available information, it is likely this pathway would have represented only incidental, short-term exposure.
6. DDOU is drained by Mill and Four-Mile creeks. Both Mill and Four-Mile creeks are irrigation ditches fed by mountain runoff and springs (2). Surface water and sediment studies showed insignificant differences in contaminant concentrations taken from sample points entering (upstream) and leaving (downstream) DDOU. Industrial areas are upstream of DDOU. DDOU will determine if further surface water and sediment analyses are needed. ATSDR will review the information as it becomes available. Although limited, the current surface water data indicate that contamination does not exist at levels of concern and the water could be used for watering crops, lawns, or livestock.
Until remediation is complete, continued surveillance of the shallow groundwater is recommended to ensure that the contamination plume does not affect off-post potable or irrigation wells.
1. All contaminants exceeding their comparison values should be included in the list of future analytes (Table 4).
2. A systematic means of continued surveillance of private well use should be established. Institutional controls should be implemented to prevent future well construction in or near the groundwater contamination areas. The Technical Review Committee (TRC) may be a means to arrange implementation of both surveillance and institutional controls.
3. Because groundwater may be used for drinking by residents west of the DDOU boundary, and because the drinking water is probably not filtered prior before use, metals could be ingested. Seven private wells west of the depot boundary will be sampled and their use determined if requested by the residents. ATSDR recommends that the analyses include unfiltered metals samples.
4. Sampling should be conducted periodically to ensure that contamination does not reach the deep aquifer. ATSDR agrees with routine sampling of existing DDOU deep wells that was requested by EPA.
5. There are no plans at this time to remove debris from the Ogden Nature Center. Areas with suspected debris or visible debris should be restricted and marked such as with signs. ATSDR, also, recommends that DDOU and the Ogden Nature Center collaborate when future pond sites are selected and that subsurface surveys be conducted in any areas scheduled for excavation. Using those surveys to guide land management decisions should prevent human exposure.
The public health action plan (PHAP) for DDOU NPL site contains a description of actions to be taken at and in the vicinity of the site subsequent to the completion of this public health assessment. The purpose of the PHAP is to ensure that this public health assessment not only identifies public health hazards, but provides a plan of action designed to mitigate and prevent adverse human health effects resulting from exposure to hazardous substances in the environment. Included is a commitment on the part of ATSDR to follow up on this plan to ensure that it is implemented. The public health actions to be implemented by are as follows:
- In accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended, DDOU has been evaluated for public health actions. The public health assessment for the above NPL site was reviewed by the Health Activities Recommendation Panel. Because there is no indication that human exposures to site contaminants at levels of public health concern are occurring or have occurred, the site is not being considered for ATSDR follow-up health activities at this time. If during the remediation process, however, data become available indicating that people are being exposed to hazardous substances at levels of public health concern, ATSDR will reevaluate the site for any indicated follow-up activities.
- PCB transformers were stored outdoors in the facility engineering section. PCB contamination as high as 23 ppm was measured in surface soil near the transformer storage area. During the initial site visit, ATSDR recommended sampling surface soil in the adjacent playground area because runoff from the transformer storage area drains to the playground area. DDOU collected surface soil samples from the playground and adjacent drainage areas in April 1992 (24 samples). PCBs were detected in five samples at concentrations ranging from 0.17-2.13 ppm. PCBs are not considered a contaminant of concern at those levels.
- DDOU plans to excavate soil from areas on the playground where PCBs were detected above 0.5 ppm (6). Future runoff from the storage area will be prevented by berming or some other means.
- DDOU has conducted an electromagnetometer survey of Burial Site 1 and it showed subsurface anomalies, possibly indicating additional burial areas or other ground disturbances. During the second ATSDR visit, DDOU agreed to share the study with the Ogden Nature Center. Additionally, ATSDR recommends collaboration between DDOU and the Ogden Nature Center when future pond sites (or other construction projects) are selected so that they are not constructed in suspected burial areas. ATSDR recommends that subsurface surveys are also conducted in any areas of suspected contamination for which construction projects are scheduled, but no previous surveys exist.
- EPA is requesting routine sampling of existing deep wells on DDOU. Results of the data on those samples will be used to evaluate the potential for adverse public health effects from exposure to contaminants in groundwater.
- DDOU will sample seven private wells west of the depot boundary and determine their use if requested by the residents. Results of the data on those samples will be used to evaluate the potential for adverse public health effects from exposure to contaminants in groundwater. ATSDR recommends that the analyses include unfiltered metals samples.
- ATSDR will provide an annual follow up to this PHAP, outlining the actions completed and those in progress. This report will be placed in repositories that contain copies of this public health assessment, and will be provided to persons who request it.
ATSDR will reevaluate and expand the PHAP as needed. New environmental, toxicological, or health outcome data, or the results of implementing the above proposed actions may determine the need for additional actions at the DDOU NPL site.
Defense Facilities Assessment Section
Federal Programs Branch
Edward W. Gregory, Jr., PhD
Defense Facilities Assessment Section
Federal Programs Branch
Environmental Health Scientist
Defense Facilities Assessment Section
Federal Programs Branch
Glenn J. Tucker, PhD
Senior Regional Representative
ATSDR Region VIII, Denver, CO
Ogden City. Statistical Review. 1989.
Defense Depot Ogden, Utah. Detailed Analysis of Alternatives Technical Memorandum for Operable Unit 1. February 8, 1991.
Defense Depot Ogden, Utah. Draft Final Remedial Investigation/Feasibility Study for Operable Unit 1. July 26, 1991.
Army Environmental Hygiene Agency. Surface Water and Sediment Sampling Plan for Defense Depot Ogden, Utah. January 29, 1990.
Defense Depot Ogden, Utah. Request for Public Comment to Proposed Plan for Operable Unit 1. October 3, 1991.
Defense Depot Ogden, Utah. Request for Public Comment to Proposed Plan for Operable Unit 2. June 15, 1990.
Defense Depot Ogden, Utah. Request for Public Comment to Proposed Plan for Operable Unit 3. March 14, 1992.
Defense Depot Ogden, Utah. Request for Public Comment to Proposed Plan for Operable Unit 4. December 6, 1991.
Defense Depot Ogden, Utah. Transcript of Public Meeting Regarding Operable Unit 1. October 17, 1991.
Defense Depot Ogden, Utah. Transcript of Public Meeting Regarding Operable Unit 2. July 2, 1990.
Defense Depot Ogden, Utah. Transcript of Public Meeting Regarding Operable Unit 4. December 17, 1991.
ATSDR. Toxicological Profile for Benzene. May 1989.
ATSDR. Toxicological Profile for Cis and Trans 1,2-Dichloroethene. December 1990.
ATSDR. Toxicological Profile for 1,2-Dichloropropane. December 1989.
ATSDR. Toxicological Profile for Vinyl Chloride. August 1989.
ATSDR. Toxicological Profile for Arsenic. March 1989.
ATSDR. Toxicological Profile for Chromium. July 1989.
ATSDR. Toxicological Profile for Polychlorinated Biphenyls. June 1989.
ATSDR. Preliminary Health Assessment for Ogden Defense Depot Ogden, Utah. March 15, 1989.
Utah Cancer Report. Number 14, Cancer Incidence in Utah by County. March 1990.