PUBLIC HEALTH ASSESSMENT
JANESVILLE, ROCK COUNTY, WISCONSIN
The Wheeler Pit is a former gravel quarry located near Janesville, Wisconsin. The General Motors Company used the site as a disposal site for paints, solvents, fly ash, fertilizers and other wastes from 1960 to 1974. Initial testing indicated that groundwater underlying the site is contaminated with metals and organic compounds. However, the final remedial investigation (RI), completed in 1989, failed to detect significant groundwater contamination at the site. The RI also concluded that the surface soils and soils beneath the waste are not heavily contaminated. Waste materials in the landfill contain a number of metals and polyaromatic hydrocarbons (PAH). Solvent vapors were present in test pits at the site. Testing of nearby private wells in 1984 and 1992 did not reveal site-related contaminants in these wells, although one contained trace amounts of trichloroethylene in 1981. Off-site wells in the direction of groundwater flow do not contain hazardous levels of contaminants. No off-site wells contain contaminants at a level of health concern.
This site poses no apparent public health hazard. To ensure that this site will not pose a publichealth hazard in the future, monitoring wells, especially those along the southern edge of the site,should be monitored at appropriate intervals for potential solvent and metal contamination.
The Wheeler Pit is a 15-acre gravel quarry located east of the City of Janesville in La PrairieTownship, Rock County, Wisconsin, at the intersection of County Highways O and J (SeeAppendices A and B). Actual dumping was limited to approximately 4 acres located in a depressionin the gravel pit The property was placed on the federal National Priorities List in September 1984. In this report, the term "site" refers to the 15-acre quarry property and "disposal area" refers to the3.82 acres where dumping took place.
The Chicago, Milwaukee, St. Paul and Pacific Railroad Company (now CMC Corporation) boughtthe site in 1900. The quarry was initially used as a source of gravel and later for refuse disposal. The property has been leased since 1956 by General Motors (GM) and was used for disposal ofdebris from its nearby truck manufacturing plant until 1974. Between 1960 and 1974 GM disposedof over 22 million gallons of compacted paint sludge , stripping residues, clarifier sludge and fly ashin the disposal area. The sludge and ash were contained by a dike on the north and west sides of thedisposal area. A fertilizer/farm supply service, presently abandoned, and an asphalt company alsooperated on a 20-acre parcel north of the site. Since 1959, the Rock County Highway Departmenthas stored road salt along highway J at the eastern edge of the gravel pit.1
In 1971, liquid slurry was noticed seeping to the surface of the disposal area along the dike, and laboratory analysis revealed the composition of this material to be similar to paint and paint booth scraping samples obtained from GM.1 Soil analysis for metals that year by Soil Testing Services, Inc. yielded inconclusive results. In 1974, the Wisconsin Department of Natural Resources (WDNR) requested that GM close the site and analyze groundwater in accordance with WDNR regulations. In 1975, the disposal area was closed, covered with 0-2 inches of cover material (soil, gravel and clay), graded and seeded.
In October, 1975, WDNR began requiring quarterly groundwater testing for "indicator parameters"(see "Environmental Contamination and Other Hazards" below) and this sampling continuedsporadically for the next eleven years.1 The site was nominated by WDNR for the NationalPriorities List (NPL) in 1983, and a Consent Order requiring GM and CMC to undertake aRemedial Investigation (RI) was signed in 1987. The RI, which was completed in 1989, consistedof groundwater and soil monitoring and a risk assessment.
On September 28, 1990, the U.S. Environmental Protection Agency (EPA) issued a Record ofDecision which outlined the following remedy for the site: consolidation of waste, installation of amulti-layer cap and commencement of a program of groundwater monitoring both on the site and atnearby residences. Construction of the remedy, which incorporated all of these elements, wascompleted in October 1992.
Representatives of the Wisconsin Division of Health (WDOH) conducted a site visit on May 15,1990. Highway "O" runs parallel to and within 75 feet of the site. Automobile access to the site isvia a paved driveway on Highway J. Access to the site was unrestricted (no fences or warning signswere visible) and a gate across the driveway was open during the visit.
A ditch approximately one foot deep runs between the driveway and the site. Despite recent heavyrains, no water was visible in the ditch. Across the ditch a large mound, about two feet high, definesthe boundary of the disposal area. Slight erosion is visible along a steep slope on the southern sideof the mound. Atop the mound is a relatively flat area under which the waste is buried. Trees,brush, and grasses are growing over the waste. Portions of the site are heavily wooded. Lockedgroundwater monitoring wells and barrels (identified as soil boring products) were found throughoutthe site. Otherwise, no garbage, foul odors, or liquid seepage were observed.
An open gravel pit is located adjacent to the site on the property occupied by the asphalt plant. Thispit contained large amounts of concrete, asphalt and other types of general refuse. The asphalt plant,which used the gravel pit, appeared to be abandoned. Numerous large tanks, vats, and drums arestill present at the asphalt plant. A trailer with an apparently functioning well appeared to be in useon the asphalt plant property. Along Highway O, a flat area of gravel was apparently the formerlocation of the fertilizer and pesticide plant. The Rock County salt storage shed along highway Jappeared to be in operation and was located about 100 yards from the site.
The nearest home is about 200 feet east of the site boundary. Three other homes are 100-200 yardssouth of the site. There are homes on farmland to the south and east, and residences in Janesville tothe west. Corn was growing in fields 100-200 yards from the site. Farm houses, gardens, and farmanimals are within one-half mile of the site. There is an expanding industrial area containing a farmchemical distributor and the State Motor Vehicle Licensing Division one-half mile north of the site. Surface water runoff from the site likely flows west to a depression in the former gravel pit. Therewere no obvious gullies or ditches on the site.
The site was again visited by a WDOH representative on July 5, 1993. Trees have been removedfrom the waste area, which has been capped and regraded such that surface water flows readily tothe perimeter of the cap. The cap was covered with gravel and vegetated topsoil. A drainage ditchleading to a seepage pond surrounded the cap.
The only vehicle access was from the driveway west of the site. A six-foot chain link fence toppedby barbed wire surrounds the waste area, the site driveway, the seepage pond and the monitoringwells to the south. Locked gates were present on both the east and west sides of the site.
The Wheeler Pit site is located in a rural area one-half mile east of the City of Janesville, Wisconsin(population 51,000). Interstate Highway 90 is about one-half mile west of the site and urbanizationis occurring along the highway corridor. Land adjacent to the site and the gravel pit is planted withcrops. No crops are grown on the site and hunting on site is unlikely because of the site's small size.
Four major aquifers underlie the site: unconsolidated sand and gravel deposits, two distinct limestone units and sandstone.2 The sand and gravel deposits, which are approximately 350 feet deep, are the source for drinking water wells in the area, including those of the City of Janesville. Groundwater flow in the area is to the west-southwest, toward the Rock River, located approximately two miles west of the site.
Depth to groundwater at the site is approximately 30 feet. Six private wells are located within one-quarter mile of the site, two to the south, two to the east, one to the north and one to the west. Three Janesville municipal wells are within a two mile radius of the site: Well 6 (97.5 feet deep) is approximately 2-1/2 miles northwest, Well 7 (105 feet deep) is approximately 2 miles west-northwest, and Well 8 (120 feet deep) is approximately 1-1/4 miles north-northwest, all on the same side of the Rock River as the site.3
A WDOH representative presented preliminary results of the Wheeler Pit health assessment at a meeting held on Aug. 8, 1990. The meeting, which was attended by approximately 25 people, was held to present EPA's proposed remedy for the site and accept public comments on the proposed remedy. At the meeting, no specific concerns relating to health effects were discussed. No health complaints related to the Wheeler Pit have been received by local public health agencies4. None of those who commented on the public comment release of this health assessment (February 19 - March 19, 1993) identified community health concerns (Appendix D).
This section describes contamination and other hazards associated with the Wheeler Pit Superfundsite. Contaminants of concern are selected for further analysis in the following sections. Environmental sample results are summarized in this section as they apply to both on-site and off-site contamination. Detailed accounts of each sample and results from analysis can be found in theWDNR files for this site and the RI Report for the site.
Ten soil borings taken in 1974 when monitoring wells were installed revealed an eight-foot thickness of cinder ash and paint sludge.5 No further analysis of the waste or soil was performed at that time.
During the RI, test pits were excavated in 1988 and 1989 in an attempt to define the specific area ofwaste disposal. In addition, seven soil borings were taken in April 1989. Contaminants weremeasured in surface soil, in the waste pit itself and in the soil under the waste and compared with"background" levels found in samples of uncontaminated soil taken approximately 500 feetnortheast and 200 feet east of the waste boundaries. Both "background" locations are uphill fromthe waste burial site.
Samples of surface soil, waste and subwaste soil were taken from soil at the waste disposal area and from soil about 200 feet west of the disposal area (see Appendix B). At the western location, cadmium was found in the surface soil at a 0.36 milligrams per kilogram (mg/kg), approximately twice the maximum found in a background sample.6 No other metals, volatile organic compounds (VOCs) or semivolatile organic compounds (SVOCs) were found in surface soil at elevated concentrations.
Lead was found in four soil borings at concentrations up to 1000 times background levels. Cadmium was also found at concentrations up to 10 times background levels. A number ofpolyaromatic hydrocarbons and unidentified SVOCs were found in the test pits but not at levels ofhealth concern. Toluene (0.41 - 85 mg/kg), ethylbenzene (1.4 - 53 mg/kg) and xylene (1.9 -370 mg/kg) were found in all four test pits. Tetrachloroethylene (0.3 mg/kg) was found in one soilboring. These contaminant concentrations are not likely to pose a health concern if the waste is leftundisturbed. See "Air and fugitive dust" below for a description of potential hazards from disturbedwaste.
Air and fugitive dust.
Air from inside the newly excavated test pits was analyzed during the RI. No details were provided in the RI regarding depth of sampling. This analysis revealed xylenes (514 milligrams per cubic meter [mg/m3]) and ethylbenzene (128 mg/m3) in the test pits. The authors of the RI state, "Field air contaminant screening with a photoionization meter on the surface of the site did not reveal evidence of volatile chemicals,"7 but no details about this sampling are provided. No other air or fugitive dust sampling has been performed at the site.8
At the time of the landfill closure in 1974, GM installed eight monitoring wells on the CMCproperty and two on the asphalt plant property to the north. Two more monitoring wells, one in thesouthwest corner of the site and one about 200 feet south of the site, were installed in 1984. Thesewells were analyzed sporadically until 1986 for "indicators" (chromium, zinc, iron, pH, biologicaloxygen demand, chemical oxygen demand, conductivity, alkalinity, and hardness), and phenol. Some samples were analyzed for lead, selenium and silver. This sampling indicated the presence ofarsenic, cadmium, chromium, and lead (Table 1) at levels above Wisconsin groundwater standards.
|Contaminant||Maximum Concentration 1974-86 (pre-RI)||Maximum Concentration 1988-89 (RI)||Comparison Value||WI Groundwater Enf. Std.|
|Total 1,2-Dichloroethylene||ND||62||70% |
|100 (cis) |
µg/L = micrograms per liter = parts per billion
* 1974-1986 samples were drawn from wells with galvanized steel screens, which could lead to erroneously high values.9 See "Quality Control and Quality Assurance".
+ Agency for Toxic Substances and Disease Registry Child Environmental Media Evaluation Guide
@ Calculated from EPA Reference Dose
# EPA Maximum Contaminant Level
& EPA 10-6 Cancer Risk Level
% EPA Lifetime Health Advisory
Prior to the RI, samples were analyzed for VOCs (toluene, trichloroethylene, benzene, xylenes andtetrachloroethylene) and some SVOCs in 1981 and 1986 and once for polychlorinated biphenyls(PCBs) and pesticides in 1984. Bis(2-ethylhexyl)phthalate and di-n-octylphthalate were detected in1981 (Table 1) but no pesticides or PCBs were found in 1984. Tetrachloroethylene was detected in1981 at 0.1 µg/L.
The results from groundwater samples analyzed before the RI are difficult to interpret because (1)the sampling took place sporadically, (2) it was not performed using currently acceptable methods(see "Quality Assurance and Quality Control" below) (3) only metals and "indicators" wereanalyzed for on more than one occasion and, of these compounds, only zinc and iron were analyzedwith enough frequency to observe temporal patterns, and (4) only wells P1 to P8 were monitoredthroughout the study period; monitoring began in wells "A" and "B", the two wells located outsideof the disposal area, in 1983 and residential wells were only sampled once in 1981.
Zinc concentrations peaked in 1976-79 in wells P1 (23.5 feet deep), P4 (23.5 feet deep), P5 (47.5feet deep), P6 (37.5 feet deep), and P7 (27.5 feet deep). Iron concentrations followed a similarpattern. Zinc concentrations through time at these wells are presented in Table 2. Locations of thewells are shown on the map in Appendix C. Well P5 was abandoned in 1979.
mg/L = milligrams per liter = parts per million
During the RI, six on-site wells were constructed and sampled in Sept.-Oct. 1988 and in April 1989and four new wells were constructed and sampled for all VOCs, SVOCs and metals on the EPATarget Compound List in April 1989. The results of groundwater sampling in the 1988-1989 RIare summarized in Table 1. Most exceedances were found in one 33.6-foot deep well locatedapproximately five feet southwest of the disposal area.
"Nitrate + nitrite nitrogen" exceeded the Wisconsin Groundwater Enforcement Standard of 10 mg/L at all monitoring wells, with a maximum concentration of 19 mg/L. No pattern of high nitrate concentrations could be identified. Since nitrate concentrations exceed 10 mg/L in 10% of the wells in Wisconsin,10 wastes buried in the Wheeler Pit cannot be implicated as the sole source of the nitrate exceedances.
No off-site soil samples have been taken. Since no pathways of surface water drainage or soilerosion leading off the site were noted, soil contamination off-site is unlikely.
No off-site air monitoring has been performed. Since the site is vegetated, little wind erosion of soilis likely.
Two monitoring wells, one approximately 300 feet south of the boundary of the waste disposal area (well "B") and one approximately 200 feet east of the waste disposal area but within the site boundaries (well "A"), were sampled during the RI. These wells were constructed in 1984, prior to the RI. Cadmium and chromium were found in both wells (0.5-0.8 µg/L and 3.5-3.8 µg/L, respectively; both below state standards of 10 and 50 µg/L) while BEHP was detected only in well "B" at 2 µg/L. Lead or arsenic were not detected in these wells. 1,2-dichloroethylene was also detected in well "B" but appeared to be a laboratory contaminant.11
Two wells supplying private residences are located approximately 1,000 feet south of the site. Testing by WDNR for metals, VOCs and SVOCs in 1981 revealed traces of tetrachloroethylene (0.03 µg/L; MCL, 5 µg/L) in one of these wells.12 The detection limit for tetrachloroethylene with the method used at that time was 0.02 µg/L.13 WDNR last tested this well and another residential well within 1,000 feet of the site in 1985. No contamination was found at that time.14
In 1986, General Motors analyzed groundwater samples from one well about 100 feet south of the site only for organic compounds and found BEHP (5 µg/L) and 1,4-dichlorobenzene (3 µg/L). A number of organic compounds were also tentatively identified in this sample but not at levels of health concern.15 Off-site monitoring was not performed with enough regularity to analyze time trends in contaminant levels.
The two residential wells and monitoring well were analyzed in January and March 1992 and no metals or VOCs were found at a level of health concern. However, nitrates were found in one residential well at a concentration exceeding the Wisconsin Groundwater Enforcement Standard.16
There are substantial differences between the results of the pre-RI and RI groundwater sampling. Two possible scenarios may explain this result. The first is that the waste pit was releasingcontaminants into groundwater over the first ten years since the pit was closed, and thatcontamination has now dispersed. The second possible explanation is that quality control in earlieranalyses was not as rigorous as that in the RI. For example, 1971 data provided by Soil TestingServices, Inc., is not clearly presented. In addition, groundwater samples taken in the late 1970s andearly 1980s may not have been filtered and the galvanized steel screens used in the wells may haveled to erroneously high results.7
In the RI, precautions were taken in order to insure the validity of the data. In the first round ofanalysis (Oct. 1988), identical samples were analyzed by Warzyn Engineering Inc. and by JacobsEngineering Inc. Results of the two analyses were similar.
Many of the data values are highlighted in the RI indicating that "The associated numerical value isan estimated quantity, because quality control criteria and/or holding times were not met." Thesedetects include many of the SVOC results from surface soil samples and VOC samples fromgroundwater. No further explanation is given for these flags.
There were no apparent physical hazards directly over the waste. Within 500 feet of the waste, stillwithin the site boundaries, there were many physical hazards including glass, metal, empty vats,large steel tanks (20-30 feet high), platforms, and containers of chemicals. The open refuse disposalarea in the gravel pit contained large amounts of old concrete with reinforcing bars and piles of oldasphalt and other materials.
A Toxic Chemical Release Inventory (TRI) search was conducted of the east Janesville and LaPrairie area zip code (53546) for any previously reported toxic chemicals. Certain manufacturersare required to report to the U.S. EPA releases or transferrances of specific hazardous chemicals. This reported information is entered into the automated TRI system. Results of a computer searchdisclosed no reports of hazardous substance releases or transferrances for this zip code.
This section of the assessment describes how people may become exposed to contaminantsoriginating from the site. The phrase "Completed Exposure Pathways" refers to situations wherethere are clear indications that people were exposed to contaminants from the site and for whichthere is sufficient information to evaluate that exposure. The "Potential Exposure Pathways" sectionrefers to exposures where there is insufficient information to link the chemical to a known level ofexposure among an identified population. For each pathway, we describe the chemicals of concern,how the chemicals move to where people may be exposed to them, and the people who may beexposed. This section describes how contaminants could migrate from the site to areas where peoplecould be exposed to them.
Contaminants may leave the soil through percolation into groundwater or through surface erosion. In general, metals and SVOCs remain bound to soil while VOCs are more mobile.17 At present, movement of metals and VOCs through soil does not appear to be significant since levels in groundwater both on and off the site are low. However, data taken before initiation of the RI indicates that contaminants may have left the soil, entered the groundwater and moved off-site (See "Groundwater" below). In addition, tetrachloroethylene was found in one soil boring taken during the RI and was found in 1981 in one on-site and one off-site well. At present, surface soil erosion is unlikely since a cap and dense vegetation covers most of the site.
The site appears to be too small to harbor any significant populations of game animals, and there areno streams or ponds for fishing in the vicinity. Cattle or dairy cows on nearby farms may consumecontaminated groundwater but in the absence of recent groundwater testing of nearby wells it isdifficult to estimate the potential importance of this pathway.
A culvert along Highway O periodically drains into the site during rainstorms, causing localizedflooding. Standing water on the site presumably evaporates or drains into the aquifer. Otherwise,there is no surface water on the site.
While low levels of contaminants were found in groundwater during the RI, groundwater may havecontained higher contaminant levels in the past. Two facts suggest that contaminants may have leftthe soil, entered groundwater, and possibly travelled off-site. First, groundwater zinc and ironconcentrations peaked in 1979, three years after installation of the cap, and then declined. Zincconcentrations in 1984 ranged from 2 to 10 percent of the peak levels. Other contaminants whichwere not analyzed may have followed similar patterns.
Second, since VOCs tend not to bind as tightly to soil as metals, VOCs could have leached and flowed in groundwater more rapidly than metals. Tetrachloroethylene was found in 1981 in groundwater from Well P2, one of the deeper wells (40 feet) in the southwest corner of the site, and in well water from a residence located approximately 1,000 feet southwest of the site. On-site groundwater was not analyzed for VOCs prior to 1981. Groundwater under the site flows west-southwest at approximately 30 to 360 feet per year with little to no vertical gradient.18 Therefore, contaminants in groundwater under the site would be expected to flow in this direction.
Air monitoring over the site did not reveal any site-related contamination. In addition, the site is completely vegetated, making fugitive dust emissions from the site unlikely. However, contaminants may be released in dust and vapors arising from soil disturbed during a digging or building operation.19 A proportion of the VOCs that reached residential water supplies would be released into air inside the homes as water is used.
There are no completed exposure pathways at this site.
Soil ingestion is not expected to be a source of contaminant exposure. One surface soil sample onthe site contains cadmium at a concentration twice the maximum found in a background soil sample. However, this concentration is not of health concern. Thus, ingestion of surface soils by trespassersis not expected to provide significant contaminant exposure. Moreover, the area is sparselypopulated and, during the site visits, there was no evidence of trespassers on the site.
Ingestion of contaminated groundwater is another potential source of contaminant exposure in thepast, present, and future. Drinking water from one well located in a home about 1,000 feet south ofthe site may have contained 0.03 µg/L of tetrachloroethylene when tested in 1981. Nocontamination was found in this and one other nearby well in 1984, and no site-related contaminantshave been detected in the Janesville municipal wells. However, the possibility that contaminatedgroundwater was consumed either prior to or after 1984 cannot be excluded based on available data.
Nitrate concentrations exceed the Wisconsin Groundwater Enforcement Standard at approximately10% of the rural wells in the State. Since no nitrate plume appears to be flowing from the site at themoment, this exceedance may be due to agricultural chemical use in the site area rather than fromwastes buried at the site.
No air emissions are expected from undisturbed soil on the Wheeler Pit site, so inhalation exposureis not expected to be significant under normal conditions. When waste was consolidated during siteremediation, xylene, ethylbenzene, and other VOCs may have been released, but safety measureswere followed to minimize workers' exposure to airborne contamination. People using homes whereVOC contaminated water supplies would breathe VOCs released into the air from tap water.
Potential pathways of dermal absorption are mainly through skin contact with contaminated surfacesoil. Surface soil does not contain any contaminants at levels of health concern. Another potentialpathway for dermal exposure would be from showers and bath water in homes with VOC-contaminated water supplies.
There is no evidence that people are being exposed to contaminants from this site at levels of healthconcern. The major public health concern is that the plume of groundwater contamination either hasaffected or will spread to drinking water supplies of people downgradient from the site. Thecontaminated aquifer serves as the only source of drinking water for the area. Workers may alsoinhale VOCs when consolidating waste at the site. The relevant health effects for each chemical ofconcern are described below.
There is convincing evidence from several epidemiological studies that ingesting arsenic increases an individual's risk of developing skin cancer. If individuals were exposed for a lifetime to the highest concentration found in the groundwater on site, they may have a moderately increased risk of contracting skin cancer. However, researchers have questioned whether the level of cancer risk associated with arsenic exposure which was noted in the epidemiologic studies is valid for the lower dose exposures that may result from drinking water containing 32 µg of arsenic per liter (the maximum concentration found on site). There is some evidence that exposure to arsenic at levels typical of most people's diets (between 10 and 50 µg per day) may be essential or beneficial to health but this positive effect has not been rigorously established.20
Ingesting and inhaling 1,4-dichlorobenzene may possibly cause cancer in humans because oral exposures in laboratory animals are associated with cancer of the liver and kidney. There are no studies regarding cancer in humans following exposure to the chemical via inhalation, ingestion or dermal absorption. No measurable increase in cancer risk would be expected from such exposure to contaminated groundwater at the site. No other health risks would be expected.21
The human health effects of long-term, low-dose exposure to 1,2-dichloroethylene are not known. The potential for either isomer (cis or trans) to cause cancer in humans or laboratory animals has not been studied. A decrease in hematocrit and hemoglobin levels was observed in male rats exposed for 90 days to a concentration 5,000 times the maximum level found in groundwater at the site. No data are available about the chronic effects on humans or animals from exposure to the chemical.22
Ethylbenzene was detected in air inside one of the test pits at 128 mg/m3. No ethylbenzene has been detected in groundwater at or near the site. Throat irritation and chest constriction were reported in human volunteers exposed to 2,000 mg/m3 but 55.3 mg/m3 did not produce any respiratory effects; the concentration inside the test pit may be associated with similar effects. Other effects noted in animals acutely exposed to ethylbenzene include alterations in liver enzyme activity upon 4-day exposure to 1,200 mg/m3. The carcinogenicity of ethylbenzene via inhalation has not been evaluated.23
Tetrachloroethylene was found in 1981 in groundwater on site and in one residential well nearby. Ingesting or inhaling tetrachloroethylene may cause cancer in humans because such exposures to laboratory animals cause cancer of the liver and kidney. There are only limited data linking exposure with cancer in humans. No increase in cancer risk would be expected from such exposure to the low levels found in groundwater at the site. No other health risks would be expected.24
Xylene was detected in air inside of one of the test pits at 514 mg/m3.7 No xylene has been detected in groundwater at or near the site. In humans, inhalation exposure to 100 mg/m3 xylene has been associated with breathlessness and irritation in the nose and throat. Renal and hepatic enzymatic activities have been found to be changed in rats and mice exposed acutely to 50 ppm xylenes. Finally, acute human exposures to 229 mg/m3 xylene have been associated with impairment in a variety of tests of central nervous system function.25
"Health outcome data" is a phrase referring to records of death and disease. When there is evidencethat people near a site have been exposed to contaminants at levels that could lead to an increase inrates of death or disease, a review of health outcome data may be appropriate. A review also may beappropriate if there are reports of unusual clusters of diseases near a site. There is no evidence ofsignificant public exposure to chemicals from the Wheeler Pit, and WDOH is not aware of anyreports of clusters of chronic disease near this site.
As discussed earlier, no health concerns related to the site have been expressed by the community to date.
The Wheeler Pit is a former gravel quarry located near Janesville, Wisconsin. The General MotorsCompany used the site as a disposal site for paints, solvents, fly ash, fertilizers and other wastes from1960 to 1974. Initial testing indicated that groundwater underlying the site is contaminated withmetals and organic compounds. However, the final RI, completed in 1989, failed to detectsignificant groundwater contamination at the site. The RI also concluded that the surface soils andsoils beneath the waste are not heavily contaminated. Waste materials in the landfill contain anumber of metals and polyaromatic hydrocarbons (PAH). Solvent vapors were present in test pits atthe site. Testing of nearby private wells in 1984 and 1992 did not reveal site-related contaminantsin these wells, although one contained trace amounts of trichloroethylene in 1981. Off-site wells inthe direction of groundwater flow do not contain hazardous levels of contaminants.
No off-site wells contain contaminants at a level of health concern.
The Wheeler Pit poses no apparent public health hazard. Nearby residents' water supplies containno detectable VOCs and no metals at levels of health concern. Contaminant concentrations insurface soil, waste and surface water also pose no apparent public health hazard.
- Wells on the southern edge of the site and well "B" (about 300 feet south of the waste disposal area) should continue to be monitored to determine if contaminant movement is occurring.
- Any future activities at the site requiring exposure to contaminants by excavation workers should incorporate appropriate safety measures.
The WDOH and ATSDR's Health Activities Recommendation Panel (HARP) reviewed theinformation about this site to decide if more action of health-related concerns is appropriate. Suchaction might include carrying out more detailed studies on cases of disease near a site or arrangingform educational programs about exposure to toxic chemicals at a site. Because human exposure tocontaminants is not likely to have occurred at the Wheeler Pit site, no additional health activities areneeded at the site. The WDOH and ATSDR will determine the need for further health activities ifhigh levels of contamination are released when the site is cleaned up or if new information shows that public exposure is greater than expected.
The WDOH, in cooperation with ATSDR, will conduct the following activities to respond to the recommendations of this assessment:
- Provide continuing public health education as new information related to public health issues becomes available;
- Review and comment on public health aspects of sampling and subsequent activities to be done pursuant to the Record of Decision, after the lead agency overseeing the investigation provides copies of the plans to the WDOH;
- Advise and consult with the Wisconsin Department of Natural Resources and the EPA onpublic health concerns that may arise as new information about the site becomes available.
Division of Health
Wisconsin Department of Health and Social Services
ATSDR REGIONAL REPRESENTATIVE
Regional Services, Office of the Assistant Administrator
ATSDR TECHNICAL PROJECT OFFICER
State Programs Section, Remedial Programs Branch
Division of Health Assessment and Consultation
This Wheeler Pit public health assessment was prepared by the Wisconsin Division of Health undera cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). Itis in accordance with approved methodology and procedures existing at the time the public health assessment was begun.
Technical Project Officer, SPS, RPB, DHAC
The Division of Health Assessment and Consultation, ATSDR, has reviewed this public health assessment and concurs with the findings.
Robert C. Williams
Director, DHAC, ATSDR
- Warzyn Engineering Inc. (1989). Remedial Investigation Report, Wheeler Pit Site, La Prairie Township, Rock County, Wisconsin: Report 13728.99. Madison, WI, pp. 8-23.
- Remedial Investigation Report, p. 27.
- Hahn, Norman, Hydrogeologist, Wisconsin Department of Natural Resources. 1983. Personal communication cited in Sause, Anne, U.S. Environmental Protection Agency, 1983, Hazard Ranking Score for the Wheeler Pit. Apr. 28, 1983.
- Krause, Helen, Public Health Nurse, Rock County Health Department. Personal communication, 4/2/92.
- Lindorff, David, WDNR Hydrogeologist. 1981. Hydrogeologic evaluation of Wheeler Pit, Janesville. Memorandum to Skip Glor, Southern District, DNR, 4/14/81.
- Remedial Investigation Report, Table 12.
- Remedial Investigation Report, p. 78.
- Remedial Investigation Report, Table 26.
- Dadisman, John, (5/16/90). Chemist, Warzyn, Inc., Personal Communication.
- Hennings, R, DE Lindorff and MD Lemcke. 1991. The condition of our groundwater resource. In: Born, SM and DA Yanggen, eds.: Working together to manage Wisconsin'sgroundwater -- next steps? Madison, WI: University of Wisconsin Extension, pp. 13-32.
- Remedial Investigation Report, Table 14.
- Remedial Investigation Report, Appendix N.
- Degenhart, David, Organic Chemist at the Wisconsin State Laboratory of Hygeine. 4/29/92. Personal Communication.
- Remedial Investigation Report, Appendix N.
- Warzyn Engineering Inc. 1988. Remedial Investigation and Feasibility Study, Wheeler Pit Site: Work Plan 13256, Madison, WI.
- U.S.Environmental Protection Agency. 1992. Analytical Data Report: Wheeler Pit Site, Janesville, WI. Analyzed March 17, 1992.
- Agency for Toxic Substances and Disease Registry. 1989. Toxicological Profiles for Lead, Xylenes and Di(2-ethylhexyl)phthalate. Atlanta, GA.
- Remedial Investigation Report, p. 39.
- Remedial Investigation Report, Table 26.
- Agency for Toxic Substances and Disease Registry. Draft Toxicological Profile for Arsenic. October 1991.
- Agency for Toxic Substances and Disease Registry. Draft Toxicologic Profile for 1,4-Dichlorobenzene. October 1991.
- Agency for Toxic Substances and Disease Registry. Toxicologic Profile for 1,2-Dichloroethylene. December 1989.
- Agency for Toxic Substances and Disease Registry. Toxicological Profile for Ethylbenzene. December, 1990.
- AGency for Toxic Substances and Disease Registry. Toxicological profile for tetrachloroethylene. October 1991.
- Agency for Toxic Substances and Disease Registry. Toxicological Profile for Total Xylenes. December, 1990.
COMMENT: A comment dated March 10, 1993 suggested that the Public Health Assessmentinclude a description of the remedy for which construction was completed in October 1992. Thecommentor also noted that the safety measures recommended in the Public Health Assessment wereincorporated by the workers during construction of the remedy.
RESPONSE: The requested additions have been made.