PUBLIC HEALTH ASSESSMENT
BARNWELL, BARNWELL COUNTY, SOUTH CAROLINA
The Shuron Plant began operations in 1958 as Shuron Continental Optical Company, a former divisionof Textron Inc. The facility manufactured single and multi-vision ocular lenses. In April 1985, thefacility was sold to a group of private investors and operated as Shuron, Inc. This group of investorsfiled for bankruptcy in 1991 and ceased operation early in 1992. The site was added to the U.S.Environmental Protection Agency's (EPA) National Priorities List (NPL) in December 1996.
The Shuron site represents no apparent health hazard. This means that there is no information that arearesidents or others near the site have been exposed to site-related chemicals above levels of concern. We have no information at this time that anyone, either children or adults, are drinking watercontaminated with chemicals from the site. However, if the City of Barnwell #10 well were to becomecontaminated, people could be exposed to several chemicals above levels of concern. No contaminantswere detected in 1996, the last time this well was sampled. No contaminants were detected in themonitoring well closest to the public well. Although groundwater at the site does not flow toward the public well #10 we cannot say with certainty that this well will not be affected by contaminants at thesite. At a minimum, the well should be sampled more frequently than once every three years, preferablyannually.
On-site groundwater is contaminated by high concentrations of volatile organic compounds (VOCs) andinorganic compounds. We know that groundwater and soil are contaminated with site-related chemicals,but believe that no one is being exposed. We do not know if anyone has been on the site frequentlyenough to have been exposed to site-related chemicals in the soil. We believe it is possible that peoplewho used to work at the site could have been exposed to chemicals in soil before the plant was closed.
Trespassers, both children and adults, and any workers on site could be exposed to chemicals presentin soil at the site, but adverse effects are not likely as long as people are not on the site for more thanthree days a week. Since most of the site is fenced, exposure to site-related chemicals in soil is unlikelyto occur.
The following recommendations have been made: monitor the City of Barnwell well #10 at leastannually; complete a biological survey of Turkey Creek to determine if water quality has been affected by operations at the site; and ensure that access to the site continues to be restricted.
The South Carolina Department of Health and Environmental Control (SCDHEC), under a cooperativeagreement with the Agency for Toxic Substances and Disease Registry (ATSDR), evaluated the publichealth significance of the Shuron, Inc. (Shuron) site. SCDHEC-Health Hazard Evaluation (HHE)determined whether exposure to contaminants is likely to cause adverse health effects and recommended actions to reduce or prevent possible health effects. ATSDR is authorized by theComprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), asamended by SARA, to conduct public health assessments at hazardous waste sites.
Shuron, Inc., is on Clinton Street in Barnwell, Barnwell County, South Carolina (Figure 1, AppendixA). The site consists of a 34-acre upland area used as the manufacturing facility and a 51-acre low landarea east and south of the building. The site is bordered by residential areas to the north and west, awetland and Turkey Creek to the east, a railroad right-of-way to the south (Figure 2, Appendix A). Theclosest homes are on Clinton Street across the street from the site and just east of the facility/parking lot. Approximately one-third of the 34-acre facility is paved or occupied by the plant building. The 34-acrepart of the site includes the manufacturing plant building, four waste water settling lagoons , and twosolid lagoons (Figure 3, Appendix A). Other important features of the site include underground fueloil tanks; fill/debris area to the south of the building where polishing compounds and solids weredeposited; a boiler spill area where materials from boiler "blow down"were deposited; and the dischargepipe outfall south of the plant building.
Shuron Inc., began operations in 1958 as Shuron Continental Optical Company, a former division ofTextron Inc. The facility manufactured single and multi-vision ocular lenses. Lens blanks were groundand shaped using grinding and polishing compounds. The grinding process utilized primarily aluminumoxide and garnet; the polishing process used oxides of iron and zirconium. In April 1985, the facilitywas sold to a group of private investors and operated as Shuron, Inc. This group of investors filed forbankruptcy in 1991 and ceased operations early in 1992. In 1994, the site was added to the EPA'sSuperfund Accelerated Cleanup Model (SACM) list and added to the U.S.EPA National Priorities List(NPL) in December 1996.
During its operation, the Shuron facility produced about 270,000 gallons per day (gpd) of waste watercontaining fine-grained grinding and polishing compounds, solvents, and waste oils. Trichloroethenewas used as solvent to clean the lenses after the grinding and polishing process. Floor drains collectedwaste water which was discharged into the basement treatment facility. The waste water was thendischarged to the waste water settling lagoons east of the plant building. Lagoon #1 was in operationuntil 1976, when three additional lagoons (Lagoons #2,3,4) were constructed. Waste water from thelagoons was discharged to the Northern Drainage Ditch that drains to the wetlands. SCDHEC monitoredthe waste water discharge until the facility ceased operations.
There have been many environmental investigations at the Shuron site over the years. The first formalinvestigation was a 1983 biota investigation of Turkey Creek. Texidyne, Inc., conducted a biologicalstudy as required by SCDHEC in conjunction with the facility's National Pollution DischargeElimination System (NPDES) permit renewal. Samples of insects and other organisms were collectedin Turkey Creek near the railroad bridge. The study reported that the waste water discharge did notappear to affect the organisms that live in Turkey Creek.
In 1984, Shuron, Inc. installed monitoring wells MW-1, 2, 3, and 4 in conjunction with the constructionpermit issued for the four Wastewater Settling Lagoons. These wells were sampled on several occasionsbetween 1984 and 1987. Contaminants were not detected at levels above the U.S.EPA MaximumContaminant Levels (MCLs). In 1987, Westinghouse Environmental Services, Inc. (WESI) sampledfour groundwater wells and found several VOCs and metals above MCLs in three of the four wells.Elevated levels of metals, VOCs, and semi-volatile organic compounds (SVOC) were also detected ingroundwater and waste water samples collected by the SCDHEC in 1987. In 1988, WESI sampledwaste, sludge , and soil at the Wastewater Settling Lagoons, Solid Lagoons, and Fill/Debris Area. VOCswere detected at low concentrations in each of the three areas. In 1990, a groundwater assessment wasconducted by WESI, which included the installation of five new monitoring wells (MW-5 through MW-9). Samples collected from new and existing monitoring wells indicated the presence of elevated VOCsand metals near the solid lagoons.
In 1991, SCDHEC completed a Site Screening Inspection which included the collection of several soil,sediment, waste, and groundwater samples. Groundwater samples were collected from monitoring wellsMW-5, MW-8, MW-9, and the City of Barnwell Well #10 (Well #10). VOCs and metals exceedingtheir respective MCLs were only detected in MW-8.
In November 1993, the U.S.EPA collected one water sample from Wastewater Settling Lagoon #2 andtwo sediment samples from the two solid lagoons. In March 1994, the U.S.EPA collected four sedimentsamples in the Northern Drainage Ditch area and two soil samples from one location at the Fill/DebrisArea. Elevated levels of VOCs, Semivolatile Organic Compounds (SVOCs), and metals were detectedin sediment samples.
The Remedial Investigation (RI) and Feasibility Study (FS) were completed by ENSR, Inc. in 1997. In November 1997, the U.S. EPA released the proposed remediation plan for the site to present cleanupalternatives for the site. Most of the data presented in the Environmental Contamination Section of this document were obtained from the RI/FS.
On November 20, 1997, Dianne Minasian, Tracy Shelley, Eric Melaro, and Enayet Ullah fromSCDHEC-HHE visited the Shuron Site and the surrounding community. Conditions at the site havenot changed significantly from the observations noted in the previous site visit of March 17, 1997. Theentire site is surrounded by a chain-link fence. A few 55-gallon drums remain in the concrete yard northof the plant building. Several waste piles containing broken fans, rusted drums, wood and metal scraps,and concrete blocks were noted immediately south and east of the plant building. Once inside the fence,access to the plant building is not restricted as there is an open door on the south side of the building;however, the site is fenced. Overgrown vegetation and trees cover the Fill/Debris area. Drum scrapswere noted outside the on-site building. Project staff noted a soda can and a snack bag inside the fence.
During the first visit, staff noted an opening in the fence near the main gate. During the second visit wenoted that this opening was not secured completely. No identifying signs from EPA or other warningsigns (including a contact address and phone number) were posted around the perimeter of the site. According to the U.S. EPA, as of August 1999, conditions at the site since the 1997 site visit have not changed.
This site is located in Barnwell County which has a 1990 U.S. census population estimate of 21,640. There are about 1,000 people living within one-half mile of the site; 130 of these people are children. About 2,600 people live within one mile of the site. The demographic profile of the population aroundthe site includes a population that is 65% white and 35% black. This is about the same as the State, but slightly different from Barnwell County where the population is 57% white and 43% black.
Land use surrounding the Shuron Site is residential and commercial. Areas directly east and south ofthe site are mainly wetlands and undeveloped. There are several businesses on Highway 64 near thesite (Figure 2, Appendix A). Two high schools and a library are approximately 1-mile from the site. The site topography slopes gently to the east, southeast with elevations ranging from about 190 feetabove mean sea level (msl) on the west of the site to about 160 feet above msl toward the southeasternportion of the property near Turkey Creek. Two intermittent streams collect runoff from the facility anddrain to the wetlands area. Turkey Creek is about 1,700 feet east of the facility.
Groundwater is the primary source of drinking water in the Barnwell area. The aquifer system includesa surficial aquifer, upper and lower Floridan aquifer, Black Mingo aquifer, and Cretacious aquifer. The Pleistocene alluvial terrace unit, which is a part of the surficial aquifer system, is the most prevalentunconfined aquifer in the vicinity of Barnwell. The City of Barnwell's public water supply system haseleven wells within a 4-mile radius of the site. These wells are screened in confined water-bearing unitsat depths 165 to 314 feet below land surface and draw approximately three million gallons of water ina day. One of the City of Barnwell's wells (Well #10) is approximately 300 feet southwest of theShuron facility, across Clinton Street from the site. Based on information from the City of Barnwell,Well #10 produces approximately 500 gallons per minute (gpm) and is screened in four water-bearingunits at depths of 180-185 feet, 210-215 feet, 225-235 feet, and 275-295 feet. These depths correspondto water bearing units in the lower portion of the Floridan aquifer, the Black Mingo aquifer, andpossibly the uppermost portion of the Cretaceous aquifer system.
During phase I of the RI, the EPA conducted a private well survey within half a mile radius north andwest of the site. The EPA identified only one abandoned private well north of the site during the privatewell survey. In 1998, SCDHEC-HHE identified eight private wells within two miles of the site;however, none are used by homeowners for drinking water. Most of these wells are more than 100 feetdeep. There are no private wells between the site and Turkey Creek. All residents within the city limitsuse public water for their water supply. A few of the residents use their wells to water the yard or wash cars.
No health outcome data are readily available for review for the community of Barnwell.
HHE staff contacted the SCDHEC Environmental Quality Control (EQC) and Health Districts forinformation regarding health concerns related to the Shuron Site. Neither of the offices have reportsof site-specific health concerns. In 1994, the EPA prepared a Community Relations Plan (CRP) forthe site. At that time the community did not express any site-specific concerns. They were angeredand frustrated about losing their jobs when the plant was shut down.
The EPA held a public availability session in November 1997, and public meetings in December1997 and January 1998. HHE staff attended all three meetings to determine if the communityexpressed any health concerns about the site. There were only a small number of residents at thesemeetings and they did not voice any site-specific health concerns. The residents expressed a greatdeal of concern about the future use of the site. One community member expressed that lowattendance at the meetings did not mean that community has no concerns.
In January 1998, HHE mailed a general fact sheet and a response card to 774 residents livingapproximately in a one mile radius of the site. The purpose of the mailing was to gather informationabout concerns residents may have about the site. Two hundred and seven cards were returned. Thecommunity expressed concerns about increased cancer rates, asthma and allergies, bronchitis,gastritis, reflux, groundwater contamination, quality of Barnwell City water supply, and use ofTurkey Creek for fishing and recreational purposes. A detailed listing of community concerns and responses is presented in Appendix B.
In April 1999, the draft public health assessment was released for public comment. There were no comments received during the 30-day comment period.
Data presented in this section are from the final Remedial Investigation Report and Feasibility Study(RI/FS). These documents represent the latest available data for the Shuron site. Data weregenerated in three phases (Phase I, II, and III) as part of the RI during 1995 and supplementalinvestigations in March and April 1996.
SCDHEC-HHE selects and discusses these contaminants based upon the following factors:
1. Concentrations of contaminants.
2. Field data quality, laboratory data quality, and sample design.
3. Comparison of on-site and off-site concentrations with public health assessment screening values for (1) non-carcinogenic endpoints and (2) carcinogenic endpoints.
Screening values for public health assessments are contaminant concentrations in specific media thatare used to select contaminants for further evaluation. These values include U.S. MCLs, thosecalculated by SCDHEC, ATSDR's Environmental Media Evaluation Guides (EMEGs), and otherrelevant guidelines. EMEGs are derived from ATSDR Minimal Risk Levels (MRLs). EMEGS arethe estimate of a daily human exposure to a chemical likely to be without an appreciable risk of non-carcinogenic adverse effects. U.S.EPA MCLs are the maximum permissible levels of contaminantsin public water. The South Carolina Water Classification and Standards (SCWCS) are themaximum permissible level of contaminants in surface water developed by the state of South Carolina for protection of human health.
The following source areas were identified and characterized as part of RI: the Boiler Spill Area onthe north side of the plant building where materials from boiler "blow down" apparently weredeposited; the Underground Fuel Oil Tanks; the Fill/Debris Area south of the building wherevarious polishing compounds and other solids were deposited; the Southern Discharge Pipe Outfallsouth of the building; the Wastewater Lagoons; the Solid Lagoons; and, the Northern DrainageDitch. Adjacent on-site areas characterized during the RI included the on-site wetland areas east ofthe facility and the Southern Drainage Ditch south of the facility (Figure 3, Appendix A).
Phase I included the collection of 76 surface soil samples (0-1foot), 52 subsurface soil samples (1-10 feet), two groundwater samples, 31 surface water samples, and 31 sediment samples. Inaddition, six surface soil samples were collected for asbestos analysis. Phase II of the RI includedthe collection of 29 groundwater samples via hydro punch, 27 groundwater samples from new andexisting wells, 45 surface soil and 25 subsurface soil samples. As part of the Phase III investigation,the following samples were collected: groundwater from ten new and nine existing monitoring wells;22 surface soil samples, 14 subsurface soil samples, and nine sediment samples. In addition, 13Phase I surface soil sample locations were resampled during Phase III. The supplementalinvestigation activities conducted in March and April 1996, were designed to verify previousanalytical results at selected groundwater and surface water locations, and measure the hydrauliccharacteristic of the upper water-bearing unit. This included collection of four additionalgroundwater samples, two surface water and sediment samples, screening of soil samples with a field Gas Chromatograph (GC) for selected VOCs, and collection of 22 subsurface soil samples.
Soil at the site has been extensively sampled and evaluated. Surface soil samples were collectedfrom 189 locations and subsurface soil samples were collected from another 68 locations. Soilinvestigations at the site revealed that surface soil (0 to 1 feet in depth) and subsurface soil (1 to 10feet in depth) at the site are contaminated with VOCs, SVOCs, and inorganic compounds. Arsenic,barium, and lead were the only chemicals present above screening levels (Tables 1C and 2C,Appendix C). Generally, inorganic compounds are present at higher concentrations in the surfacesoil, while VOCs are higher in the subsurface soil. Samples collected in the Fill/Debris area and theSolid Lagoon area contained the highest levels of site-related chemicals. The highest levels ofinorganic compounds in subsurface soil were detected near the Wastewater Lagoons area. Althoughbackground samples were collected, they were collected on-site, and two of the six samples did nottruly represent background because they were fairly close to the facility.
Groundwater samples were collected from shallow, intermediate, and deep aquifers. There are nooff-site monitoring wells. Only one background well out of two truly represents backgroundconditions. Twenty-five shallow (unconfined aquifer) monitoring wells were sampled to assess thehorizontal extent of contamination in shallow groundwater. These wells were screened from 5.8 to18 feet below land surface (bls). Intermediate groundwater samples were collected from eightmonitoring wells screened from 50 to 65 feet bls. Deep groundwater samples were collected fromfive monitoring wells screened between 79 to 185 feet bls.
Volatile organic compounds, SVOCs, and inorganic compounds are consistently present in theshallow and intermediate groundwater at the site. A number of chemicals, primarily VOCs, arepresent above screening levels (Table 3C, Appendix C). The highest concentrations are present inthe wells near the Solid Waste Lagoon and near the Fill/Debris area. Trichloroethene (TCE)(5µg/L) was the only chemical present above screening levels (MCLs) in the deep aquifer at thetime of the investigation. TCE was found in monitoring well 252, which is south of the SolidLagoon area.
The deepest monitoring well (MW-238) was screened at a depth of 175 to 185 feet below landsurface which is similar to the uppermost screen interval of the City of Barnwell supply well #10. This monitoring well is just west of the Shuron building, between the site and the public well #10.The uppermost screened interval of Well #10 is at a depth of 180 to 185 feet. Although no VOCs orSVOCs were detected above detection limits in this monitoring well, TCE was detected in another deep well just south of the lagoons.
Surface water and sediment samples were collected from the lagoons, northern and southern ditches,and the wetlands (east of the site) (Figure 2, Appendix A). VOCs, SVOCs, and inorganiccompounds are present in surface water and sediment samples collected from these three areas. Thehighest concentrations in surface water are found in samples collected from several areas of the site. Trichloroethene, bis (2-ethylhexyl) phthalate ester, and lead are present at concentrations aboveSouth Carolina's Water Classification and Standards-Water Quality Criteria (Table 4C, AppendixC). The highest concentrations in sediment are present in samples collected from the Southern Ditch and the Solid Lagoon area (Table 5C, Appendix C).
ENSR collected and analyzed off-site residential surface soil (0 to 3 inches in depth), the City ofBarnwell water supply well, and surface water and sediment from Turkey Creek.
Three off-site surface soil samples were collected from (0 to 3 inches) a nearby residential yardalong Fifth Street, just north of the site. One off-site surface soil sample was collected from 0 to 1foot in depth, west of the Shuron plant building. There were no chemicals detected above screening values in any of these four soil samples.
Three pairs of surface water and sediment samples were collected from Turkey Creek. One samplewas collected east of the Northern Drainage Ditch, a second was collected adjacent to the site, andthe third sample was collected downstream of the site. There were no chemicals detected abovescreening levels in either surface water or sediment from Turkey Creek. A 1983 biological studydid not indicate that waste water discharge from the facility had affected the benthic population in Turkey Creek.
During Phase II of the RI, a water sample was collected from the City of Barnwell Well #10 and analyzed for VOCs, SVOCs, and inorganics. No contaminants were detected above the detectionlimits. SCDHEC Lower Savannah Environmental Quality Control (EQC) District samples this wellevery three years. Well #10 has been sampled by the SCDHEC in 1987 and 1991. No VOCs weredetected above detection limits. The most recent sampling, July 1996, did not detect VOCs,SVOCs, or inorganics in this well. However, this was three years ago, and we do not know thecurrent state of water quality. While on-site groundwater generally flows toward the south and east,this well is only 300 feet from the western edge of the site and could influence local groundwaterflow. To date, only trichloroethene has been detected in one on-site deep well. This on-site deepwell is south of the lagoons and is considerably shallower than the municipal well.
SCDHEC identified eight private wells within two miles of the site. None of these wells are used fora drinking water supply. Some residents reported using them for watering the yard or washingvehicles. The U.S.EPA identified one abandoned private well about 50 feet north of the site as partof their off-site well survey. The U.S. EPA attempted to sample this well during the RI, but could not collect the sample because of obstructions in the well.
The data in this section are from the Remedial Investigation Report and represent the latest availableinformation and data for this site. Quality Assurance and Quality Control (QA/QC) conclusionsdrawn for this public health assessment are determined by the validity of the analysis andconclusions made and the availability and reliability of the referenced information. SCDHECassumes that adequate quality assurance and quality control measures were followed with regard to chain-of-custody, laboratory procedures, and data reporting. Overall, the data appears to be reliable.
During the site visits, SCDHEC staff noted several physical hazards at the Shuron Site. The door onthe south of the Shuron plant building was open. Waste piles containing rusted drums, broken fans,wood and metal scraps, and other debris was noted on the loading docks immediately south of theplant building. Similar piles of refuse were also noted to the east of the building. We also noted afew rusted 55-gallon drums on the concrete yard immediately north of the plant building, within the fence at the site. The site is fenced which should limit the dangers of people hurting themselves on this debris.
The Pathways Analysis Section contains discussions of how chemicals move in the environment andhow people can be exposed to those chemicals. Environmental monitoring data has shown that on-site soil, groundwater, and surface water, are contaminated with site-related chemicals abovescreening levels.
There are two types of exposure pathways, completed and potential. Completed means that we aresure that someone has been exposed to site-related chemicals. For example, there must be a sourceof the chemical (the site), contaminated media at the site (soil), someway people can be exposed (weknow people are getting on the site), and we know people have been exposed (they are eating thedirt). In this example, people could have been exposed in the past, could be exposed now, or in thefuture. This means that someone could have been on the site five years ago, could be on the site now(a trespasser or unprotected worker) or five years from now if the site is not cleaned up (such asworkers at a new business on the site). Currently, we do not believe that people are actuallyexposed to the dirt (meaning they are on site eating the dirt) or drinking contaminated water. Therefore, we have concluded that there are no completed exposure pathways at the site.
The second type of exposure pathway is a potential exposure pathway. This means we do not haveall the information we need to determine whether or not exposure has occurred or will occur in thefuture. For example, if we know that groundwater at the site is contaminated and there is a watersupply well nearby (maybe upgradient) that could at some point in the future become contaminated,it is called a potential exposure pathway. The potential exposure pathways for the communityaround the Shuron Site are shown in Table 1. We know that for the site that groundwater and soilare contaminated with site related chemicals; however, we believe that no one is being exposed. Wedo not know if anyone has really been on the site frequently enough to have been exposed to site-related chemicals in the soil. We believe it is possible that people who used to work at the site could have been exposed to chemicals in soil.
|Exposure Pathways Elements||Time|
|Source||Environmental Medium||Point of Exposure||Route of Exposure||Exposed Population|
|Shuron||Soil||On-site|| Ingestion, |
Inhalation of Dust
|Trespassers, Workers|| Past |
|Shuron||Groundwater||Off-site|| Ingestion, |
|Residents of the City of Barnwell||Future|
Soil samples collected on the site contained several site-related chemicals above screening levels.Although both shallow (0-1 foot) and subsurface soil (0 to 10 feet) are contaminated, contact withdeep soils is unlikely to occur unless these areas are not remediated and are dug up during futureconstruction at the site. Since the site is fenced, exposure to site-related chemicals in soil is unlikely,except for the occasional trespasser or unprotected remediation or construction worker. A smallnumber of off-site soils samples were collected at a nearby residential property. There were no site-related chemicals present above screening levels. Although only a few soil samples were collectedfrom residential areas, surface water drainage is in the opposite direction, toward the wetland area,and run-off from the site is not expected to transport contaminated soils into residential areas.
In 1995, the EPA extended the fence to enclose a portion of the site near the fill/debris area andother potential source areas to prevent exposure to on-site contaminated soil. On-site workers ortrespassers may have been exposed to contaminated soil. However, no data are available to evaluatethe length of potential past exposures.
In general, shallow, intermediate, and deep groundwater beneath the site flows from northwest tosoutheast. However, from the water table contour map of the upper water-bearing unit, thegroundwater beneath the northeastern portion of the site flows eastward and groundwater beneaththe southern portion of the site flows south.
VOCs and inorganics were a concern in the unconfined, semi-confined, and confined water-bearingunits. The extent of contamination is much higher in shallow groundwater than in intermediate anddeep groundwater. VOCs, SVOCs, and inorganics present in soil may have leached intogroundwater as a result of different physical, chemical, and biological processes. No off-sitemonitoring wells were installed as part of the RI. Shallow groundwater at the site may discharge tothe wetlands and eventually to Turkey Creek.
There are 11 City of Barnwell water supply wells within 4 miles of the site. Well #10 is very closeto the site. The community is concerned about groundwater contamination at the site and its affectson Barnwell's water supply. This well is screened in four water-bearing units at depths between 180to 295 feet below land surface. The uppermost screen interval (180-185 feet) of Well #10 is 144feet below the bottom of the upper water-bearing unit and separated by five water-retarding units oflow conductivity. The one on-site monitoring well, screened at the same depth as Well #10, did notcontain any site-related chemicals. Although groundwater at the site does not flow toward the publicwell #10, we cannot say with certainty that this well will not be affected by contaminants at the site. At a minimum, the well should be sampled more frequently that once every three years (at leastannually).
Surface Water-Sediment Pathway
Surface water runoff at the site flows to the south and east. Surface water runoff from the southernhalf of the facility and the areas west of Clinton Street runs into the Southern Drainage Ditch whichthen flows to the wetlands and Turkey Creek. Surface water runoff from the northern half of thefacility runs into the Northern Drainage Ditch. This ditch also empties into the wetlands area andTurkey Creek. Shallow groundwater at the site may discharge into the Southern Drainage Ditch,the wetlands, or Turkey Creek.
The lagoons and the northern and southern drainage ditches are the most likely points of exposure. However, in 1995, the EPA extended the fence around these areas which should prevent exposures to contaminated surface water and sediments on the site . Even though it does not appear as though the site has adversely affected Turkey Creek, a general water quality survey could provide information about the health of the Creek. This information could be used to determine if further sampling of the Creek is warranted. At this point in time, exposure to Turkey Creek in the area near the site should not result in any adverse health effects; therefore, this pathway has been eliminated. The Shuron Plant closed in 1992 and it is possible that discharges to the Creek occurred when the plant was in operation. We have no information to determine if contaminants levels in the creek were a problem while the plant was in operation.
There is often little information about the health effects caused by low level environmentalexposures. Most human exposure studies use information from industrial exposures, where thedoses are much higher. Industrial exposure data normally do not include precise information aboutthe dose, the purity of the chemicals, their interactions with other substances, and the duration of theexposure. For some chemicals, there is no information available on the effects in people; therefore,we use data collected from studies using laboratory animals. Animals do not necessarily show thesame responses that humans do when exposed to toxic substances. However, in animal experimentsusing carefully controlled doses and time periods, researchers observe health effects that they believemay also occur in people.
Information is not available to be able to say with certainty that if a person were exposed tochemicals in soil at the site or in groundwater they would become sick. Most information aboutthese chemicals is usually obtained from laboratory studies. The animals in these studies aretypically exposed at much higher levels than would be expected to occur at the Shuron Site. It isvery difficult to know what levels of these chemicals at the site can cause specific health effects. Thekinds and severity of human health problems that can occur with exposure depend upon severalfactors: the amount of chemical exposure, duration of exposure, and route of exposure; body weight,age, sex, ethnic background, lifestyle factors, and genetic factors; general health of the person;individual reactions to chemicals; and, interactions with other chemicals or drugs.
In order to compare the amounts of a substance that may be taken into the body to known standards,this section uses comparison doses. These doses are based on the amount of a substance that isconsumed per day (milligrams/kilogram body weight/day, mg/kg/day). Comparison doses used inthis section include ATSDR's Minimum Risk Level (MRL), which represents an estimate of dailyhuman exposure to a dose of a chemical that is likely to be without adverse effects (for noncancerouseffects) over a specified duration of exposure, and the U.S.EPA Reference Dose, which is anestimate of the daily exposure of people to a potential hazard that is likely to be safe during alifetime (that does not include cancer). These doses represent levels at which harmful effects areunlikely to occur. They are calculated using safety factors for the most sensitive humanpopulations, and if based upon animal measurements, additional factors are used. .
Groundwater at the site is contaminated with very high levels of several VOCs and lead (Table, 3C,Appendix C). Available information indicates that no one, either children or adults, are drinkinggroundwater contaminated with chemicals from the site. The City of Barnwell well #10 would haveto become contaminated for a person to be exposed to contaminated groundwater at the site. Sincethe well is only tested every three years, we are assuming that if exposure were to occur, it wouldoccur for less than five years. Although there are quite a few chemicals listed in Table 3C abovescreening levels, only those chemicals above levels of concern are discussed in this section. If weassume the length of time people could be exposed to chemicals in groundwater is less than fiveyears rather than a lifetime, the number of chemicals of concern is decreased to five. Thesechemicals include 1,2-dichloroethene, trichloroethene, tetrachloroethene, vinyl chloride, and lead.Exposure to the other chemicals would not result in doses above their respective reference doses orMRLs. Adverse health effects would not be expected to occur from exposure to these otherchemicals because the doses are lower than the levels of concern.
A level of concern is an estimated dose, below which, adverse health effects are not expected tooccur. Levels of concern are normally U.S.EPA reference doses or ATSDR MRLs. This does notmean that if the estimated dose of the chemical is above these levels of concern a person will becomesick, but that there is an increased risk that exposure could cause adverse health effects
Exposure to 1,2-dichloroethene, trichloroethene, tetrachloroethene, and vinyl chloride may beassociated with adverse affects on the liver and kidneys. Most of this information is based on resultsfrom laboratory studies and we do not know if the same problems will occur in people. There is alsolimited evidence of a link between heart, immunological, and developmental problems in peopleexposed to trichloroethene and tetrachloroethene.
Trichlorothene, and to some extent tetrachloroethene, in drinking water in combination with otherVOCs has been associated with congenital mouth and nervous system defects and low birth weight(Bove et al., 1992), childhood leukemia, deaths around the time of birth, childhood disorders, andcongenital abnormalities (Lagakos, 1986). TCE has also been associated with leukemia andrecurrent infections (Byers et al., 1988), and heart disease (Goldberg, 1990). These studies,however, did not provide sufficient evidence that TCE causes these harmful health effects becausethe people were exposed to more than one chemical at the same time. It is difficult to determinewhich chemical or combination of chemicals would be associated with the various adverse effects.Moreover, information on other risk factors that could cause the same adverse effects was notincluded in this study.
Exposure to vinyl chloride could increase the risk of developing cancer. However, for vinyl chlorideto cause an increased cancer risk, a person would have to be exposed to the highest level found onsite. The exposure would have to be over the person's lifetime and they would have to drink a lot ofwater (more than two liters) every day.
On-site soil (0-1 foot), groundwater, and sediment contained high levels of lead. There is noU.S.EPA reference dose for lead so it is difficult to determine what levels of exposure are harmful. Children are at greatest risk of adverse health effects from exposure to lead. Exposure to lead canresult in elevated blood lead levels. Elevated blood lead has been associated with decrease inintelligence (IQ) scores, slow growth, and hearing problems in children and infants. These effectscan happen at low exposure levels and persist as the children get older. Adults do not absorb leadreadily via the digestive tract, whereas children absorb lead more readily. Most absorbed lead isstored in bones. Lead is also distributed to the red blood cells, blood plasma, kidney, liver, andbrain. This storage is cumulative and the body's burden increases over time.
On-site soil also contained other chemicals above screening levels (Table 1C, Appendix C). Lead isthe only chemical that poses a health risk to a person if they were exposed. Arsenic, barium, andlead exceeded screening levels in soil, and were also elevated in on-site sediments. As long astrespassers, both children and adult, are not exposed for more than three days a week, the risk fromthese chemicals is minimal. Since most of the site is fenced, exposure to site-related chemicals in soilis unlikely to occur. If a child were to be exposed to on-site soils for more than three days a weekfor their lifetime, the estimated dose for arsenic would only slightly exceed the level of concern. The U.S.EPA reference dose for arsenic is based on the development of skin problems in people who drank water contaminated with arsenic.
Child Health Subsection
SCDHEC's evaluation contained within this document considered children as a susceptiblesubpopulation. There are approximately 130 children within a half mile of the site. There are nocompleted exposure pathways at the site. Therefore, it is unlikely that children or adults have beenexposed to site-related chemicals at the Shuron site that could cause adverse health effects.
No health outcome data are readily available for the Shuron site.
As part of EPA's Community Relations Plan and public meetings, few residents raised health concerns about the site. During these activities, the community expressed concerns about the future use of the site. Community concerns gathered by SCDHEC through returned response cards included concerns about increased cancer rates, asthma and allergies, gastritis reflux, groundwater contamination, quality of Barnwell City water supply, and use of Turkey Creek for fishing and recreational purposes. A detailed listing of concerns and our responses is presented in Appendix B.
The Shuron Site represents no apparent health hazard. This means that available information donot indicate that area residents or others near the site have been exposed to site-related chemicalsabove levels of concern. Furthermore, available information indicates that no one, either children oradults, are drinking groundwater contaminated with chemicals from the site. No contaminants weredetected in the Barnwell #10 well the last time this well was sampled. However, if this well were tobecome contaminated, people could be exposed to several chemicals above levels of concern. Thecommunity is also concerned about the possibility that on-site groundwater can affect water qualityin this well. Although groundwater at the site does not flow toward the public well #10, we cannotsay with certainty that this well will not be affected by contaminants at the site. At a minimum, thewell should be sampled more frequently that once every three years.
Trespassers and any workers on site could be exposed to chemicals present in soil at the site, butadverse effects are not likely as long as people are not on the site every day. Lead is the onlychemical that poses a health risk to a person if they were exposed. As long as trespassers, bothchildren and adult, are not exposed to the soil for more than three days a week, the risk fromexposure is minimal. Since the site is fenced, exposure to site-related chemicals in soil is unlikely tooccur at levels that could cause adverse health effects. However, if a child were exposed to on-sitesoils for more than three days a week for their lifetime, the estimated dose for arsenic slightlyexceeds the level of concern.
Even though it does not appear as though the site has adversely affected Turkey Creek, a generalwater quality survey could provide information about the health of the Creek. This informationcould be used to determine if futher sampling of the Creek is warranted. At this point in time,exposure to Turkey Creek in the area near the site should not result in any adverse health effects. Therefore, this pathway has been eliminated.
1. Monitor the City of Barnwell well #10 at least annually.
2. Complete a biological survey of Turkey Creek to determine if water quality has been affected byoperations at the Shuron Plant.
3. Ensure that access to the site is restricted.
No further public actions by health agencies are indicated at this time.
The Shuron, Inc. Public Health Assessment was prepared by the South Carolina Department ofHealth and Environmental Control's Division of Health Hazard Evaluation under a cooperativeagreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is inaccordance with approved methodology and procedures existing at the time the public healthassessment was begun.
Technical Project Officer
Superfund Site Assessment Branch (SSAB)
Division of Health Assessment and Consultation (DHAC)
The Division of Health Assessment and Consultation, ATSDR, has reviewed this public health assessment, and concurs with its findings.
Chief, SSAB, DHAC, ATSDR
Tracy Shelley, M.S.
Division of Health Hazard Evaluation
South Carolina Department of Health and Environmental Control
ATSDR Regional Representative
ATSDR Technical Project Officer
Gregory Ulirsch and Roberta Erlwein
Superfund Site Assessment Branch
Division of Health Assessment and Consultation
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Arsenic. ATSDR. 1993.
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Barium. ATSDR.1992.
Agency for Toxic Substances and Disease Registry. Toxicological Profile for 1,2-Dichloroethene.ATSDR. 1996.
Agency for Toxic Substances and Disease Registry. Draft Toxicological Profile for Lead. ATSDR. 1997.
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Tetrachloroethylene.ATSDR. 1997.
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Trichloroethylene.ATSDR. 1997.
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Vinyl Chloride.ATSDR. 1997.
ENSR. Final Remedial Investigation Report for the Shuron Site, Barnwell, South Carolina. January1997.
ENSR. Final Feasibility Study Report for the Shuron Site, Barnwell, South Carolina. April 1997.
Klaassen, C.D., M.O. Amdur, J. Doull. 1986. Casarett and Doull's Toxicology, The Basic Scienceof Poisons. 3rd edition. Macmillan Publishing Company.
Patnaik, Pradyot. 1992. A Comprehensive Guide to the Hazardous properties of ChemicalSubstances. Van Nostrand Reinhold.
Shineldecker, Chris. 1992. Handbook of Environmental Consultant: A guide for Site Assessment. Lewis Publishers Inc.
South Carolina Department of Health and Environmental Control. Site Review Update (SRU) forthe Shuron site, Barnwell, South Carolina. May 1997.
South Carolina Department of Health and Environmental Control. Correspondence from RoseStencil, Lower Savannah EQC District, concerning information on current sampling program of theCity of Barnwell Well #10. March 1997.
South Carolina Statistical Abstract '97.
South Carolina Department of Health and Environmental Control. Water Classifications andStandards. June 1998.
South Carolina Department of Health and Environmental Control, Division of Water SupplyDrinking Water: Common Water Quality Problems And Their Treatment. March 1992.
United States Environmental Protection Agency. Proposed Plan Fact Sheet for Shuron SuperfundSite. November 1997.
United States Bureau of Census. Public Law 94-171 [Machine-readable data files]. The Bureau,Washington, D.C.1990.
United States Environmental Protection Agency. Drinking Water Regulations and HealthAdvisories. October 1996.