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The Suquamish Tribe has expressed concerns about the safety of ingesting seafood from Clam Bay. Even though tribal members currently are not harvesting from Clam Bay because fishing in the area is prohibited, there are plans to open the area and to even enhance the beach to improve the habitat for native littleneck clams.

Because the area is closed, tribal members are not currently being exposed to chemical contaminants. However, based on the elevated levels of arsenic, lead, PAHs, PCBs, and dioxins in native littleneck clams and our ingestion rate estimates, subsistence consumers should not eat those clams from Clam Bay. This recommendation is based on the likelihood of adverse health effects in subsistence consumers (children, pregnant women, and other adults). Although geoduck and sea cucumbers are currently safe to eat, (based on chemical levels only, not biological contaminant levels) any disturbances in the landfill or beach area which would occur during clean-up (remediation) efforts could stir up contaminants, forcing them into the sediment and water column further from the beach impacting these and other subtidal species. For this reason, ATSDR recommends that this area remain closed to fish and shellfish harvesting until remediation is complete and two consecutive sampling events (no sooner that 3 months apart) indicate that fish and shellfish do not contain contaminants at levels of health concern for subsistence or recreational consumers.

A local citizen expressed concerns that radioactive waste generated by the Navy in the 1940s may have been disposed of in the landfill.

Radiation was not detected above naturally occurring background levels in soil from the 17 test pits dug into the landfill. Therefore, human exposure to elevated radiation is not occurring.

ATSDR is mandated to determine if anyone has, is, or could come in contact with chemical contaminants and to stop, reduce, or prevent adverse health effects resulting from such exposures. Even though it is outside of ATSDR's mandate to pursue the matter further, we have contacted EPA which provided documentation to alleviate citizens' concerns regarding radioactive wastes generated by the Navy during nuclear testing in the 1940s.

Hart Crowser Inc. (contractor for the US Army Corps of Engineers) doing historical research for the Remedial Investigation report asked the Defense Nuclear Agency (February 23, 1995) questions regarding radioactive material. The Defense Nuclear Agency, which reviewed historical documents from the 1940s, stated that "radioactive material removed from target vessels for testing was not to be retained indefinitely by the activity concerned, but was to be disposed of by sinking at sea or by replacement on the target vessel." (as reported in the document, Chief of Naval Operations Itr Serial 0138P36 dtd Jun 10, 1947 Subject: Handling and Control of Radiologically Contaminated Material from Crossroads). Additionally, the response states "We found no indication from these documents that contaminated material from the target ships was deposited in landfills."

If anyone has any additional health concerns related to possible exposure at Manchester Annex, they can direct them to Program Evaluation and Record Information Services Branch RE: Manchester Annex, ATSDR, Division of Health Assessment and Consultation, 1600 Clifton Road, NE (E56), Atlanta, Georgia 30333.


We did not evaluate health outcome databases because people are not coming in contact with site contaminants at levels that might cause diseases.


  1. Although signs posted along the beaches of Manchester Annex warn against consuming fish and shellfish from this area, workers from EPA and NOAA/NMFS are known to consume up to 6 meals per year. No adverse health effects are likely to result from that exposure.
  2. Current contaminant levels of arsenic, lead, PCBs, and dioxins in intertidal shellfish would pose a health hazard to subsistence shellfish consumers. However, subsistence consumption is not expected to be occurring at Clam Bay because insufficient numbers of shellfish are available on the beach to support such vigorous harvesting. Additionally, access is restricted and harvesting in this area is advised against by posted signs.
  3. Although soil gas has not been detected at explosive levels, the installation of an impermeable cap on the landfill may cause any methane that is produced during natural landfill material decomposition to migrate to the buildings nearby. Army Corps of Engineers will include an evaluation of methane generation ability of the landfill and will incorporate engineering controls into the landfill remediation design to prevent methane migration into nearby buildings from creating an explosion hazard.
  4. Surface soil contamination poses no apparent public health hazard because contaminant levels are low. Additionally, workers who accidentally ingest, inhale, or dermally contacts contaminated subsurface soils stirred up during construction, environmental investigative, and remediation activities are not expected to experience adverse health effects because of the short duration and frequency of such exposures.
  5. Groundwater contamination does not present a public health hazard because no one is drinking contaminated water. Elevated contaminant levels are sporadic and infrequent and any mixing from the contaminated shallow aquifer and the Outwash Channel Aquifer, where drinking water wells are placed, would be diluted even further and would most likely be non-detectable.


Recommended Actions:
  1. ATSDR recommends that the Manchester Annex beach of Clam Bay remain closed to shellfish harvesting until remediation is complete and two consecutive sampling events (no closer than 3 months apart) indicate that contaminant levels in seafood do not pose a health hazard. ATSDR is requesting to review that data when it becomes available and will make a public health determination at that time as to whether the fish and shellfish are safe to eat.
  2. ATSDR recommends that engineering controls be used during landfill remediation to ensure that contaminated sediments are not stirred up and deposited in areas inhabited by edible subtidal seafood species.
  3. ATSDR has estimated consumption practices of subsistence harvesters based on discussions with only a few Suquamish tribal members which may not represent the actual consumption practices of the majority of the approximately 400 local tribal members living in Kitsap County. Since this area may be opened to harvesting, we would need better estimates of consumption practices. Therefore, ATSDR recommends that a scientific consumption survey be conducted of the local members of the Suquamish Tribe to more accurately evaluate their actual consumption practices as a subsistence population. ATSDR is initiating that survey in cooperation with the Washington Department of Health and the Suquamish Tribe in 1997.

Planned Action:
    ATSDR supports the Army Corps of Engineers' plan to evaluate methane production of the landfill and to use engineering controls in the remediation to prevent migration of methane laterally to upland buildings.


Carole D. Hossom
Environmental Health Scientist
Defense Facilities Assessment Section
Federal Facilities Assessment Branch
Division of Health Assessment and Consultation


Diane Jackson
Chief, Defense Facilities Assessment Section
Federal Facilities Assessment Branch
Division of Health Assessment and Consultation


  1. Hart Crowser, Draft Final Project Management Plan, J-3933-15, July 27, 1994.

  2. Hart Crowser, Draft Remedial Investigation Report Manchester Annex Superfund Site, Manchester, Washington, Volume 1 J-4191-08, March 1996.

  3. Agency for Toxic Substances and Disease Registry. Record of Communication with Bob Keivit, US Environmental Protection Agency Remedial Project Manager, July 30, 1996.

  4. Index, Administrative Record File, Manchester Annex RI/FS, June 2, 1995.

  5. Agency for Toxic Substances and Disease Registry. Record of Communication with Ken Patterson, Engineering Field Activity, Naval Facilities Engineering Command, Northwest. July 30, 1996.

  6. Agency for Toxic Substances and Disease Registry. Record of Communication with Richard Brooks, Suquamish Tribal Fisheries Department. August 3, 1995.

  7. Agency for Toxic Substances and Disease Registry, Site Visit Notes, May 31, 1995.

  8. Agency for Toxic Substances and Disease Registry. Record of Communication with Ralph Totorica, US Army Corps of Engineers, Follow-up to E-mail message. July 29, 1996.

  9. U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Guidance Document for Arsenic in Shellfish. January 1993.

  10. Larsen, EH, Pritzl G and SH Hansen. Arsenic speciation in seafood with emphasis on minor constituents and investigation using high-performance liquid chromatography with detection by inductively coupled plasma mass spectrometry. Journal of Analytical Atomic Spectrometry 1993;8(8):1075-1084.

  11. Johnson, LR and JG Farmer. Use of Human metabolic studies and urinary arsenic speciation in assessing arsenic exposure. Bull Environ Contam Toxicol 1991;46(1):53-61.

  12. Phillips, JH. Arsenic in aquatic organisms: A review emphasizing chemical speciation. Aquat Toxicol 1990;16(3):151-186.

  13. Vaessen, HAMG and A van Ooik. Speciation of arsenic in Dutch total diets: methodology and results. National Institute of Public Health and Environmental Protection. The Netherlands. Original paper translated from Z Lebensm Unters Forsch 1989;189:232-235.

  14. U.S. Environmental Protection Agency. PCBs: Cancer Dose-Response Assessment and Application to Environmental Mixtures. EPA/600/P-96/001F. September 1996.

  15. U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Guidance Document for Lead in Shellfish. August 1993.

  16. Lacey RF, et al. Lead in Water, Infant Diet, and Blood: The Glasgow Duplicate Diet Study. The Science of the Total Environment. Vol. 41 (1985).

  17. Marcus AH. Relationship Between Childhood Blood Lead and Lead in Water or Liquid Diet. Report from Battelle Columbus Division to Office of Toxic Substances, USEPA, Contract No. 68-02-4294 (Feb. 14, 1989).

  18. Marcus AH. Uptake of Lead from Formula and Food by Infants: Reanalysis of the Ryu et al. Data. Report from Battelle Columbus Division to Office of Toxic Substances, USEPA, Contract No. 68-D8-0115 (June 15, 1990).

  19. Moore MR, et al. The Contribution of Drinking Water Lead to Maternal Blood Lead Concentrations. Clinica Chimica Acta 1979;95:129-133.

  20. Ryu JE, et al. Dietary Intake of Lead and Blood Lead Concentration in Early Infancy. American Journal Dis. Child. 1983;137:886-891.

Other Documents Reviewed

    Hart Crowser, Manchester Annex RI/FS, Preliminary Scoping Old Navy Landfill and Fire Training Areas, Manchester, Washington, J-3933-15, April 14, 1994, revised September 27, 1994.

    Hart Crowser, Manchester Annex RI/FS, Addendum No. 1 to Project Management Plan, Manchester, Washington, J-4191-26, September 1, 1995.

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