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The Osborn Connecticut Correctional Facility (Osborn CCI) is located in Somers, CT. It is amaximum security prison. Until 1984, the Osborn CCI had its own sewage treatment facility onsite. The sand filter beds received tetrachloroethylene (PCE)-contaminated wastes from the on-site laundry facility. PCE-contaminated groundwater was detected in 1986 in one of the prisonsupply wells located near the former sand filter beds. In 1993, through routine investigationsunrelated to the prison, PCE was also detected in off-site private wells. The maximum level ofPCE detected was in a private well (500 ppb).

Currently, the PCE contamination on and off the Osborn CCI site poses no apparent public health hazard. Residents have been supplied filters for their household water supply and are now able to connect to the municipal water supply system. Prison officials have discontinued use of the PCE-contaminated supply well. No other possible pathways of exposure have been identified for this site, aside from past groundwater exposure.

Residents, Osborn inmates, and staff had consumed PCE-contaminated water in the past. Theseexposures were not sufficient to cause adverse health effects, nor should they impact the health ofresidents, inmates, or prison staff in the future. Available information indicates that residentshad PCE in their water supplies in 1993, with a maximum detection level of 500 ppb. Theexposure could have been up to 18 years (when the homes were built). However homes arecurrently located on the edge of the plume and it is unlikely that the exposures were as long as 18years, or that levels of PCE have ever been significantly above 500 ppb.

The maximum duration of exposure for the prison inmates and staff is 27 years. The prison beganoperation in 1963 and discontinued use of the contaminated well (well S2) in 1990. Themaximum PCE level detected (27 ppb) was in 1986. Water from the contaminated well wasmixed with water from three other supply wells, between 1986 and 1990. The average PCE levelachieved was approximately 7 ppb. In 1990, the prison discontinued use of the contaminatedwell (supply well 2), and PCE levels have been less than 5 ppb since. Again, these exposureswere not sufficient to impact the health of inmates or staff.

Area residents have several concerns including existing health conditions in the community,some that correlated with exposure. Other residents noted that there seem to be more of sometypes of illnesses (such as learning disabilities in children, headaches, and dizziness) in theirneighborhood compared to others.

Area residents also had health concerns related to the stress of coping with the discovery of PCEin their water supply. Several residents reported that the stress has negatively impacted theirhealth and quality of life.

Lingering unanswered concerns continue to aggravate stress levels. These concerns include thelack of quantitative information about the duration and extent of exposure, and whether futureremediation will protect public health.

In a letter dated February 23, 1995 to the Assistant Administrator, ATSDR, the citizens living inthe Rye Hill Circle area of Somers, Connecticut requested ATSDR to assess their exposure totetrachloroethylene (PCE).

ATSDR makes the following recommendations to protect the health of residents, inmates, andprison staff:

  • The municipal water supply system is currently available to all residents in the area, according to the Bureau of Water Management of the Connecticut Department of Environmental Protection. Residents are encouraged to connect to the municipal water supply.
  • Osborn CCI should continue supplying water to the prison facility from wells other than the PCE-contaminated well.
  • ATSDR Regional Representative, Region 1 should maintain open lines of communication withRye Hill Circle residents and discuss findings as needed in informal meetings and/or public availability sessions.


A. Site Description and History

Note: Unless otherwise specified, information in this public health assessment was obtained from the Fuss & O'Neill reports listed in the REFERENCE Section.

Osborn Connecticut Correctional Institute (Osborn CCI)

Osborn CCI has been operational since 1963. The facility is located in Somers, CT on the borderof Somers and Enfield, CT. A dry cleaning facility operated on-site, also beginning in 1963. Thedry cleaning operation generated tetrachloroethylene (PCE) waste. The PCE waste was disposed of in a drying bed (or sand filter bed) associated with wastewater treatment, (Figure 1, Appendix A). Osborn CCI operated its own wastewater treatment facility on-site until 1984. The facilitywas located on the southwestern corner of the property. The wastewater treatment facility ceasedoperation in 1984, when Osborn CCI was connected to the Enfield Sewer System.

Osborn CCI has retrieved its drinking water supply from four on-site groundwater productionwells (S1, S2, S3, and S4) and one well at the Enfield Correction Institute (Figure 1, Appendix A). The Connecticut Department of Public Health and Addictive Services (CDPHAS) begandetecting PCE in supply wells S2, S3, and at trace levels in S4. The maximum level detectedwas 27 ppb. The state provided safe drinking water to Osborn CCI by mixing the water fromthese wells with that from S-4. In August, 1990, the state removed S-2 from service because ofincreases in PCE contamination. In 1991, the state began an on-site investigation to identify thesource. In 1993, the sand filter bed (previously used for waste water treatment) was identified asthe likely primary source of PCE contamination for the aquifer. The boiler plant area was also apossible additional source.

Rye Hill Circle Area

For purposes of this public health assessment, the Rye Hill Circle area includes Rye Hill Circle,White Birch Circle, Wrights Brook Drive, Polo View Drive, and portions of George Wood Road (Figure 1 & 2, Appendix A). Homes on Rye Hill Circle, White Birch Circle, and Wrights Brook Drive were built between 1976 and 1980, and are directly southwest of the Osborn CCI.

The nearest home is approximately 75 feet from the Osborn CCI property line. In February1993, the Sanitarian for the Town of Somers found two homes with PCE levels of 170 ppb intheir private wells during a random sampling event. Private wells of homes located on Rye HillCircle were tested in March and April 1993 and forty-six (46) domestic wells indicated thepresence of PCE. Thirty-five of the 46 wells had levels of PCE between 7.9 and 500 ppb (Figure 3, Appendix A). In April 1993, the state installed granular activated carbon filters in the affected wells. Later that summer, homes located on George Wood Road, Polo View Drive, and White Birch Circle had their drinking water wells sampled. PCE was detected at concentrations ranging from 0.5 to 47 ppb. These residences were also supplied with filters. On September 2, 1993, the Connecticut Department of Environmental Protection (CDEP) identified the "Rye Hill Circle Area" as a state superfund site.

See APPENDIX D for a chronological history of events for the Osborn CCI and the Rye Hill Circle Area.

B. Actions Implemented During the Public Health Assessment Process

ATSDR completed a Health Consultation for the Somers Correctional Facility in November1994. ATSDR held a public availability session in November, 1994, in conjunction with therelease of the Health Consultation. ATSDR staff Ms. Lynelle Phillips, Dr. Frank Schnell, andMs. Susanne Simon spoke with over 30 residents and their families. ATSDR staff also met withthe Connecticut Department of Environmental Protection (CDEP), the Connecticut Departmentof Public Health and Addictive Services (CDPHAS), the Connecticut Attorney General Office(CAGO), and the Somers Pollution Control Authority. In addition, ATSDR staff attended ameeting of the Water Pollution Control Board during this visit. Fact sheets and Case Studies inEnvironmental Medicine were also provided.

ATSDR staff Ms. Lynelle Phillips and Mr. Morris Maslia met with community members inFebruary 1995. About 12 residents attended an informal community meeting at the library anddiscussions centered around continued health concerns, possible clean-up strategies, andquestions about past exposure. Community members requested that ATSDR undertakeinvestigations to better characterize the contaminated aquifer from which the wells obtaineddrinking water and estimate past exposure. During this visit, ATSDR staff also met with theCDEP, CDPHAS, CAGO, and the Water Resources Division of the United States GeologicalSurvey (USGS), Connecticut District.

C. Site Visit

During February 1995, Ms. Phillips and Mr. Maslia conducted a site visit of the propertysurrounding the Osborn CCI.

The location of prison water supply wells, on-site streams, and sample sites were noted. A prisonofficial said that neighborhood children may occasionally trespass onto the property and play inthe woods or streams. However, they are discouraged from this practice. Some tennis balls andfood wrappers were noted during the visit.

In June 1995, ATSDR staff Ms. Susanne Simon, (Region I), Mr. Morris Maslia, andrepresentatives of the USGS conducted a visit of the Osborn CCI. A pilot "pump and treat"system was connected by the CDEP to monitoring well number 8 up gradient of the Rye HillCircle area.

D. Demographics, Land Use and Natural Resource Use

In order to evaluate potential health effects associated with exposure to hazardous substances inthe environment, ATSDR obtains information on the population in the vicinity of the site("demographics"), the types of land use near the site, and natural resource use in the area.

Population information is needed because some types of illnesses and diseases are more commonin certain age groups such as the elderly or children, in certain ethnic groups, or in groups ofpeople with low income. In addition, some groups may be more sensitive to the presence ofhazardous substances in the environment. Information on education levels provides ATSDRsome guidance on what types of health communication programs may be useful near the site inthe future. Land use information is important because sensitive groups of people such as schoolchildren or residents in health care facilities may be located near the site. Use of some naturalresources, such as groundwater, may have an impact on the potential for human exposure tohazardous substances.


Osborn CCI has a male inmate population of 1436 and a staff population of 550. Other prisonsare also located within the complex. The total prison and staff population served by the on-sitewater supply wells is 5346 (3892 inmates and 1454 staff).

In 1990, Somers had a total population of 9,108. Ninety-one percent of the population waswhite. The community is very stable; 94% of the population reported having lived in the sameresidence for five years or more. Somers had a normal age distribution, with 7% of thepopulation five years and under, and 9% 65 and older. Median family income was $58,445 andthe median home value was $207,600. Less than 2% of the population live below the povertylevel (1990 US Census Bureau).

The Rye Hill Circle area is an upper middle class neighborhood with a population ofapproximately 145, half of which are children. About 10 individuals are over the age of 60.

Land Use

The Osborn CCI property covers 550 acres with 49 buildings on site. The property waspurchased by the State of Connecticut in 1960 from Shaker Farms. The land was formerly usedfor agriculture.

Currently, the facility is surrounded by residential, agricultural and undeveloped marsh andwoodland. The Osborn CCI is bordered to the west by two other correctional institutions, theEnfield Medium Security Facility and the Robinson Correctional Facility.

A waste treatment plant was operated on the Osborn CCI land, prior to 1984. The facility used awaste treatment system that consisted of a waste treatment plant, a series of sand filter beds, andtwo sludge drying beds. This system was demolished in 1984, when the facility was tied into theEnfield sewer system. The sand filter beds are now considered to be a significant source of PCE-groundwater contamination (Figure 1).

The Rye Hill Circle area began development in 1976 and is comprised of residential homes Thearea is located south and east of the site. The nearest residence is 75 feet southwest of the site. There are no parks, daycare centers, schools or medical facilities in this neighborhood. Many ofthe residences have in-ground or above-ground swimming pools. Land use is typical ofresidential areas.

Natural Resource Use

Groundwater is the main natural resource used in this area. The Osborn Correctional Facilitycurrently operates three wells on-site that serve the five correctional institutions in Somers andEnfield. A fourth well is on-site, but was removed from service because of extensive PCEcontamination. A fifth well is located at the Enfield Medium-Security Facility (Figure 1).

The Rye Hill Circle area residents continue to retrieve their water supply from private wells. Residents have been provided with granulated activated carbon filters to remove volatile organic compounds before use. Currently a municipal water line has been connected into the Rye Hill Circle area.

Both the Rye Hill Circle residents and the on-site supply wells receive their water from the underlying bedrock aquifer. The on-site supply wells were drilled between 1955 and 1960 to final depths of 500 to 900 feet. Drilling records indicate that the wells in the Rye Hill Circle area vary in depth from 88 to 205 feet. These private wells yield between 6 to 30 gallons of water per minute.

Two streams (Wright's Brook and Woods Stream) flow parallel to each other across the property. Woods Stream is located on the western portion of the site and receives approximately two-thirds of the drainage from the site, while Wright's Brook is located on the eastern portion of the site and receives one-third of the drainage. Both streams flow towards the Rye Hill Circle area. There are no intake pipes for drinking water supplies along the 15 mile downstreampathway. These areas may be used for recreational purposes by area children (Figure 1, Appendix A).


ATSDR believes identifying and addressing community health concerns relevant to this site iscritically important to the Public Health Assessment. Community concerns were communicatedduring several community meetings attended by ATSDR staff, and through phone contact andletters. This section identifies community health concerns regarding possible health effects ofthis site.

Residents of the Rye Hill Circle area voiced concerns about the general health status of theirneighborhood, and the possible relationship to their past PCE exposure (ATSDR 1993, ATSDR 1994).

  • Some residents reported that symptoms correlated with exposure, i.e. when the PCE was removed from their water, the health problems ceased.
  • Other residents noted that there seemed to be more of some types of illnesses (such as learning disabilities in children, headaches, dizziness) in their neighborhood as compared to others.
  • Many requested that ATSDR staff determine whether these health effects could havebeen caused by the PCE exposure.

During a public availability session in November 1994, residents provided (self-reported) healthhistories of themselves and their children. These histories and other health concerns werediscussed privately during the public availability session.

The following is a summary of all the information provided by these residents:

Number of histories: 75
Number of children's histories (<18 years old):
Average age of adults:
Average age of children:
Average years of residence:

Physiological systems reported most frequently included the following:

  • the central nervous system -
  • (headaches with varying severity, dizziness, migraines, nocturnal seizure (1), and disorientation)
  • the reproductive system -
  • (irregular menstruation and menstrual difficulties, infertility)
  • the skin -
  • (rashes, hives, eczema, and hair loss)
  • the gastrointestinal system -
  • (stomach upsets, loss of appetite, weight gain)
  • the musculoskeletal system -
  • (fatigue, muscle/joint/back pain)
  • the endocrine system -
  • (abnormal functioning of pancreas, pituitary, and thyroid)
  • the cardiovascular system -
  • (palpitations, racing heart rate, numbness of extremities)
  • the respiratory system -
  • (lung problems and asthma).
  • Cognitive processes most frequently reported as affected included: memory loss, short attention span and difficulty concentrating, depression and anxiety.
  • Developmental delays in children were frequently reported in the areas of learning, language, motor abilities, and behavioral problems. Several area children were diagnosed with attention deficit disorders of some type.
  • Birth defects include reports of small numbers of cases with missing or deformed digits, weak immune systems, and skin discoloration.
  • Other reports include a small numbers of cases of fibrous breast disease and pre-cancerous cervix.
  • Residents of the Rye Hill Circle area also had health concerns related to the stress of coping withthe discovery of PCE in their water supply. Several residents reported that the stress hasnegatively impacted their health and quality of life. These concerns include the following:

    • the lack of quantitative information about the duration and extent of exposure to PCE prior to its discovery in their water supply in 1993.
    • the adequacy of remedial decisions being made regarding the PCE contamination of theaquifer supplying residents' private wells, and whether they ensure that public health willbe protected in the future.

    Further discussions regarding the summary of health histories and the above health concernsincorporate information about environmental contamination, exposure and toxicologicalanalyses. See the Health Outcome Data and Community Health Concerns Evaluation Section which appears later in this document.

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