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  1. From the information reviewed, ATSDR considers the locations in the study area with substantively contaminated private well water to be a public health hazard because of long-term exposures to hazardous substances. Exposure to VOCs is occurring or has occurred principally through ingestion of drinking water and inhalation of indoor air-borne vapors and aerosols released through household water use. Dermal absorption is a less important groundwater exposure route.
  2. ATSDR believes that the available well sampling data may not fully characterize groundwatercontamination within the total study area or identify all well locations at which contaminantexposure may have occurred or may be occurring. Reasons include the following:
    • uncertainty exists about contaminant source(s) and location(s); for example, state and localagencies express concern about potential on-lot sewage sources,
    • uncertainty exists about the direction and rate of groundwater flow,
    • uncertainty exists about changing contaminant patterns over time,
    • some wells shown to contain no, or low, contaminant levels were last sampled as long as 7years ago,
    • one well on Bristol Pike, south of Penn Valley Road sampled in 1987 had unacceptable levelsof contaminants; and it's uncertain whether the well is still being used,
    • available data show that contamination can be absent at a well and present in an adjacent wellwithout apparent evidence of a predictable pattern or cause.
    • only 29 of an estimated 55 wells in use in 1990 in the study area have been sampled
  3. Persons using nearby lakes for recreation might be intermittently exposed to VOCs, primarily through incidental ingestion and inhalation. ATSDR expects the concentrations in lake waters and consequent exposures are not likely to be substantial; however, the available surface water sampling data are not sufficient to confidently evaluate the plausible exposure issues.
  4. People are likely to inhale VOCs that may occur in ambient air in the workplace or in residences either through volatilization of chemicals during domestic use (showering and cooking) of contaminated groundwater or from soil gas migration into structures. Limited soil gas measurements and an analytical review of groundwater/soil gas chemical equilibrium suggest that migration of soil gas from below ground into buildings is a plausible concern. ATSDR believes that building floors and subsurface walls cannot always be counted on to effectively prevent soil gas intrusion. The absence of interior ambient air data makes it impossible to confidently evaluate plausible inhalation exposure issues.
  5. Workers outdoors at Corco Chemical could have been exposed to contaminants in soil through ingestion or inhalation of contaminated particles. Data are not available for determining whether contaminants are present in surface soils around the Para Scientific building or the landfill east of Cedar Lane.
  6. Non-VOCs that have a strong potential to bioaccumulate in biota might be present in sediments in the lake west of Corco Chemical and might be taken up by the food chain. If so, consumption of fish from that lake could result in contaminant exposure. However, information about fish consumption and sediment data are not available to evaluate that plausible pathway.
  7. Community members have expressed concern about a variety of health effects and theirpossible association with the contaminated drinking water. Possible deviations in cancerincidence and mortality rates have been investigated by local health authorities; their findingsindicate there is no increased cancer rate in the Falls Township area. No association with otherreported health effects and exposures to contaminants can be established at this time.


Characterization and Cease/Reduce Exposure Recommendations

  1. Private wells - All residents in the area should be encouraged or required to connect to thepublic water system when it is completed. ATSDR believes that within two years, it would beappropriate to conduct a survey to determine whether there are any wells in the study area thatcontinue to be used either for drinking water or for household purposes (showering, cooking,etc.), or both. After completing that survey, the well sampling programs previously conductedshould be expanded in a manner that will confidently show whether groundwater from any wellsin use contains contaminants at levels of public health concern. Well users whose water containscontaminants at levels of concern should be firmly advised to discontinue such uses. Ownersalso should be advised that filter systems require periodic long-term maintenance.

    Because of the uncertainty of contamination sources and movement in the groundwater, it isappropriate to continue periodic sampling of all private wells in the future to determine whetherwater quality has changed.

  2. Surface water - Within 2 years, it would be appropriate to sample surface waters in Van Sciver Lake (sample initially near the extension of Penn Valley Road), in the lake west of Corco Chemical (sample adjacent to the property), the lake east of Corco Chemical (sample near the cooling water outfall), and Warner Lake (sample area closest to the Meenan Oil recovery operation) to confirm whether contaminants are at levels of health concern.
  3. Ambient air and soil gas - Within 2 years initiate monitoring of interior air for VOCs at several residences or businesses in the study area to determine whether contaminants are present at levels of health concern. At least one location should be on East Penn Valley road where contaminant levels have been highest in well water, and at least one should be near Corco Chemical where substantive levels of VOCs have been detected in soil gas in subsurface soils. Also conduct interior air monitoring at Corco Chemical. Using the results of those analyses, consider conducting similar testing at Para Scientific Company. If analyses warrant, advise owners of steps they might initiate to mitigate elevated air concentrations in homes or in the workplace.
  4. Soils - Conduct sampling of surface soils around the Para Scientific building and at the landfill east of Cedar Lane to determine whether any contaminants are present at levels of health concern.
  5. Fish - At the lake west of Corco Chemical, where non-VOCs may have accumulated in sediments, it would be helpful to know whether eating fish from the lake poses a public health hazard. Consider 1) sampling lake sediments near the Corco Chemical property; or 2) initiating a survey of the community to determine whether there is substantive fishing in the lake; or 3) testing edible portions of fish taken from the lake. Of those three options, testing fish flesh is the most direct method of addressing whether fish consumption might pose an unacceptable exposure.
  6. Sample analyses - Most samples should be analyzed at least for the compounds on EPA'sTarget Compound List (TCL) and Target Analyte List (TAL). If there are conflicting oruncertain results, resampling should be initiated. The most appropriate sampling and analyticalmethods should be selected to define the low concentrations at which many of the compoundsmay pose a public health concern.

Health Activities Recommendation Panel (HARP) Recommendations

The information and data developed in the Falls Township Petitioned Public Health Assessment,have been evaluated by the ATSDR Health Activities Recommendation Panel (HARP) forappropriate followup with respect to health activities. The locations where private well water hasbeen found to contain substantive contamination are a public health hazard because of long-termexposure to hazardous substances at levels of public health concern. The exposure occurred inthe past and still may be occurring. The panel determined the following activities are indicated:biologic indicators of exposure testing, biomedical testing, community health investigation,disease- and symptom-prevalence study, site-specific surveillance, and inclusion of exposedmembers of the community in the TCE subregistry. The panel also determined that communityhealth education and health professional education are needed. If more information becomesavailable indicating that additional human exposure to hazardous substances is occurring or hasoccurred in the past at levels of public health concern, ATSDR will reevaluate the study area forany additional indicated follow-up.


The following public health actions have developed:

  1. ATSDR concurs with the Pennsylvania State Department of Health State Cancer Control Program's efforts to investigate possible cancer clusters in the Falls Township area.
  2. As resources permit, an environmental health education program will be undertaken in the community living near this site. The purpose of the program is to advise the local public health professionals, health care providers and local residents of the nature and possible consequences of exposure to contaminants associated with the site. For health professionals providing clinical care, the value of obtaining a complete and accurate exposure history will be stressed. Information provided on the contaminants of concern may include, but not be limited to, the physical nature of the contaminants, potential pathways and exposure routes, potential health effects, symptoms of exposure, testing and treatment if known. In addition, information will be provided to residents about ways to protect their own health, and prevent adverse health effects from exposure to toxic substances.
  3. A biological indicators of exposure study and a disease- and symptom- prevalence study are recommended to address community health concerns. Those studies will be considered before a long term evaluation such as a site-specific surveillance would be addressed. As resources permit, ATSDR will work with the Pennsylvania Department of Health to implement these follow-up public activities.
  4. PADER reports that Corco Chemical Company has completed a soil and groundwater investigation, has submitted a remediation plan for groundwater, and has removed contaminated soil from around a solvent trap. PADER has approved the groundwater remediation plan, which consists of pumping and treating groundwater on Corco property (Appendix B, #5).
  5. In 1992, the Township of Falls Authority report they have made public water available to residents in their own container from the authority's Penn Valley pump station. Water mains are expected to be extended in 1994 to make the system available everywhere within the study area and also farther south, across the canal.
  6. PADER (and the Bucks County Health Department) would be willing to participate insampling programs. They expect to continue periodic VOC monitoring of water quality in bothlakes used by Corco Chemical.


Environmental Assessor:

    Don Gibeaut
    Environmental Health Engineer
    Remedial Programs Branch
    Division of Health Assessment and Consultation

Health Assessor:

    Stephanie Prausnitz
    Environmental Health Scientist
    Remedial Programs Branch
    Division of Health Assessment and Consultation

Regional Representative:

    Charles J. Walters
    Public Health Advisor
    Office of the Assistant Administrator
    Region III


  1. Petitioner for Falls Township Site. Petition letter to ATSDR. May 27, 1988.
  2. NUS Corporation. Site Inspection of Morrisville Trailer Park. March 25, 1988.
  3. Pennsylvania Department of Environmental Resources. Preliminary Assessment, Corco Chemical Corp. Undated.
  4. Mercuri and Associates. Hydrogeologic Study/Environmental Assessment of Pennwood Crossing Property. January 1987.
  5. Hydro Group, Inc. Hydrogeologic Report. April 1989.
  6. U.S. Environmental Protection Agency. Toxic Release Inventory online data base. 1990.
  7. Stanton JE. Pollution claims catch U.S. eye. The Courier Times 1990 July 31:1,4.
  8. Stark K. Some in Falls Twp. still using tainted well water. The Philadelphia Inquirer 1990 Aug 2:3,35.
  9. Bucks County Health Department. Letter with data concerning Country Lane Trailer Park. April 15, 1985.
  10. Pennsylvania Department of Environmental Resources. Data sheets concerning Falls Township site. 1982.
  11. Pennsylvania Department of Environmental Resources. Data summary concerning Falls Township site. 1985.
  12. Pennsylvania Department of Environmental Resources. Data sheets concerning Falls Township site. 1985.
  13. Aqua Pure Laboratories. Data sheets concerning Falls Township site. 1990.
  14. Pennsylvania Department of Environmental Resources. Data sheet concerning Falls Township site. 1985.
  15. Pennsylvania Department of Environmental Resources. Data Sheets concerning Falls Township site. 1992.
  16. Pennsylvania Department of Environmental Resources. Data summary concerning Falls Township site. 1982.
  17. Pennsylvania Department of Environmental Resources. Data sheet concerning Falls Township site. 1982.
  18. Pennsylvania Department of Environmental Resources. Data sheets concerning Falls Township site. 1983-1985.
  19. BCM Laboratory. Data sheet concerning Falls Township site. 1986.
  20. Pennsylvania Department of Environmental Resources. Data sheets concerning Falls Township site. 1983-1990.
  21. NUS Corporation. Site Inspection. Corco Chemical Corp. October 27, 1989.
  22. R.E. Wright & Associates. Letter concerning Corco Chemical work scope. June 21, 1990.
  23. Pennsylvania Department of Environmental Resources. Data sheet concerning Falls Township site. 1989.
  24. Pennsylvania Department of Environmental Resources. Data sheets concerning Falls Township site. 1985 and 1987.
  25. K-Mart Corporation. Letter and data sheet concerning Falls Township site. May 27, 1983.
  26. R. E. Wright & Associates. Phase I Environmental Assessment and Remedial Investigation. September 10, 1990.
  27. American Cancer Society. Answering Your Questions About Cancer. 71-1MM-Rev.2/84-No.2025-LE. 1984.
  28. Sherman J. Chemical Exposure and Disease: Diagnostic and Investigative Techniques. New York: van Nostrand Reinhold, 1988:19.
  29. Hill RN. Current EPA perspectives on animal selection and extrapolation. In Roloff MV, et al, eds. Human Risk Assessment. The Role of Animal Selection and Extrapolation. London: Taylor and Francis. 1987:11-14.
  30. Stallones RA. Epidemiology and Environmental Hazards. In Gordis L and Libauer CH, eds. Epidemiology and Human Risk Assessment. Oxford: Oxford University Press. 1988:3-10.
  31. Paustenbach DJ. A survey of health risk assessment. In Paustenbach DJ, ed. The Risk Assessment of Environmental Hazards. A Textbook of Case Studies. New York: John Wiley and Sons. 1989:27-124.
  32. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for tetrachloroethylene. Atlanta, Georgia: ATSDR, 1990.
  33. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for trichloroethylene. Atlanta, Georgia: ATSDR, 1989.
  34. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for chloroform. Atlanta, Georgia: ATSDR, 1989.
  35. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for benzene. Atlanta, Georgia: ATSDR, 1989.
  36. National Library of Medicine (NLM). Clinical Effects: Benzene. TOMES (Toxicology, Occupational Medicine and Environmental Series reference database) Vol. 8, 1987.
  37. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for 1,2-dichloroethane. Atlanta, Georgia: ATSDR, 1988 (in draft).
  38. National Library of Medicine (NLM). Integrated Risk Information System online database. 1991.
  39. Review of Residence Information from Cancer Incidence Data for Falls Township in Bucks County, Pennsylvania; Weinberg, GB and S. Staub; Bureau of Epidemiology and Disease Prevention, Pennsylvania Department of Health; November, 1992.
  40. Wilson, J Robert et al. Obstetrics and gynecology, 9th edition. Mosby-Year Book, Inc: St. Louis, 1991.
  41. Ryan, KJ et al. Kistner's gynecology: principles and practice, 5th edition. Year Book Medical Publishers, Inc: Chicago, 1990.
  42. Agency for Toxic Substances and Disease Registry. Public health assessment guidance manual. Atlanta: ATSDR, March 1992.
  43. Andreoli, TE. Cecil essentials of medicine, 2nd edition. W.B. Saunder Company:Philadelphia, 1990.

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