SECTION 1:
INTRODUCTION
This is a report on the baseline and follow-up activities and findings from the analyses of data collected from participants in the Trichloroethylene (TCE) Subregistry. The TCE Subregistry is part of the National Exposure Registry (NER), which was created and is being maintained by the Agency for Toxic Substances and Disease Registry (ATSDR).
In 1988, ATSDR issued proposed policies and procedures for the National Exposure Registry, which were reviewed extensively by several committees composed of independent scientists, state representatives, representatives of other federal agencies, and other interested persons. The revised polices and procedures were published in the National Exposure Registry Policies and Procedures Manual (1). The TCE Subregistry was the first subregistry to be established as part of the National Exposure Registry program. There are currently four chemical subregistries.
In keeping with NER goals, this report presents the latest TCE Subregistry findings, suggests specific hypotheses for future research, and summarizes ongoing research (1). Data have been collected for baseline and up to five followups. Reports on Baseline and Followup 1 data were previously published (2, 3). However, additional sites have since been added so analyses were rerun on the complete Baseline and Followup 1 data which includes the new registrants. The analyses in this report for most sites cover data from Baseline through Followup 3 (the latest available). The research presented herein focuses on the NER participants and other residential populations who have experienced similar exposures to TCE in drinking water. This report highlights some health outcomes and predictive variables that are either part of current epidemiologic or health studies or should be considered for analysis in future.
The NER Policies and Procedures Manual describes in detail all policies, procedures, and operational details for establishing the TCE and other subregistries of the National Exposure Registry (1). Specific topics from the policies and procedures document are reiterated in this report, where necessary, for clarity.
Section 2 of this report provides background information on why TCE was selected as a primary contaminant for a subregistry and how individual sites were selected. A description of each site and summary information on environmental data is presented. Section 3 provides a description of the methods employed in data collection, and also provides a detailed description of the variables used in data analysis and the analytic methods employed.
Sections 4-7 of the report provide an overview of the characteristics and health status of TCE registrants who participated in the baseline and in up to three subsequent followups. Descriptions of the TCE population at each of these time points and results of comparisons to national norms can be found in Section 4 (Baseline), Section 5 (Followup 1), Section 6 (Followup 2), and Section 7 (Followup 3).
Section 8 discusses the findings from the Baseline and all three Followup comparisons in light of published literature. Section 9 summarizes the findings of this report and discusses recommendations for future activities.
Sections on mortality and intrafile comparisons are not included in this report, although they were previously provided in the Baseline report (2). A separate report on mortality is in progress. Intrafile comparisons may be repeated at a later date for a planned longitudinal analysis.
SECTION 2: BACKGROUND
THE SELECTION OF TCE AS A PRIMARY CONTAMINANT
In 1988, ATSDR selected TCE as the primary chemical for the first subregistry of the National Exposure Registry. In keeping with ATSDR procedures for chemical selection (1), the factors that led to the selection of TCE included the ubiquitousness of TCE in the environment; published evidence of TCE toxicity in worker populations and in toxicologic studies1; and the paucity of information on low-level, long-term exposures to TCE in the environment. Each of these factors suggested that a TCE subregistry could contribute significantly to the detection of an excess in adverse human effects, should they exist, following long-term, low-level exposure to TCE in the environment.
At the time of its selection, TCE was the most prevalent contaminant found at National Priorities List (NPL) sites. In 1988, TCE was listed as present at more than 355 of 951 NPL sites. More recently, in 1997, the ATSDR environmental database, HAZDAT (5) listed TCE as being present at 891 (61.4%) of the 1,450 NPL sites.
As of 1988, the year the TCE Subregistry was established, the available literature indicated that TCE was toxic to humans and animals. A brief synopsis of the literature follows. For humans, research reported in the literature indicated that the principle targets following TCE exposure were the central nervous system (CNS), liver, kidney, and hematologic system (6). Because of the paucity of relevant study information and the uncertainties in interpreting the findings of studies reported in the literature, neither the lowest observable adverse effect levels (LOAELs) nor the no observable adverse effect levels (NOAELs) for most effects in humans, could be specified.
For example, there was limited information regarding lethality in humans resulting from inhalation or oral exposure to TCE (Table 2-1) (6). Reports of acute exposures were poorly quantified or not quantified at all. Data were available for CNS effects in humans resulting from acute and chronic inhalation exposures, but threshold concentrations for acute exposures and effect levels for chronic exposures were inadequately defined. Reports of acute oral and inhalation exposures indicated hepatic and renal effects, but exposure and dose data were not available. Although these studies were considered inconclusive, they indicated that there might be an association between ingestion of water contaminated with TCE and other chlorinated compounds and developmental effects and leukemia in humans. Little information was available for effects in humans with dermal exposure to TCE.
Studies of animals were also limited in 1988, but they too indicated some possible adverse health effects following TCE exposure (Table 2-1). Ingesting or breathing levels of TCE that were much higher than typical environmental levels could possibly produce numerous adverse outcomes such as CNS damage; liver and kidney damage; effects in the blood; tumors of the liver,
1At the time of its selection, TCE was one of the 25 chemicals on the ATSDR Hazardous Substance Priority List (4).
Table 2-1.—Availability of information (1988) on health effects of TCE (human and animal data).
Type of Effect |
Type of Exposure |
|||||
Human data |
Animal Data |
|||||
Dermal |
Inhalation |
Oral |
Dermal |
Inhalation |
Oral |
|
| Lethality | No |
Some |
Some |
No |
Some |
Some |
| Acute | No |
Some |
Some |
No |
Some |
Some |
| Intermediate | No |
No |
No |
No |
Some |
Some |
| Chronic | No |
Some |
No |
No |
Some |
Some |
| Developmental Toxicity |
No |
No |
Some |
No |
Some |
Some |
| Reproductive Toxicity |
No |
No |
No |
No |
Some |
Some |
| Carcinogenicity | No |
Some |
Some |
Some |
Sufficient |
Sufficient |
| No | = | No information available. |
| Some | = | Some information available. |
| Sufficient | = | Sufficient information exists to meet at least one of the criteria for cancer or noncancer end points. |
kidney, lung, and male sex organs; and cancer of tissues that form white blood cells (leukemia). Results of a few studies in pregnant animals exposed to TCE in air or in food showed varied effects on unborn animals or newborns. These studies identified the general range of lethality and principal toxic effects of inhalation and oral exposure to TCE, but did not fully characterize exposure- or dose-effect relationships (6). Threshold and no-effect concentrations or doses were lacking for many of the toxic effects, and some effects (for example, immunosuppression and hematologic effects) needed additional characterization.
Animal data were also insufficient to determine the health effects resulting from acute and chronic exposures. Inhalation studies (7, 8) indicated that TCE was a developmental toxicant, but an NOAEL had not been identified and an evaluation of malformations associated with oral exposure had not been conducted. The effects of oral exposure on fertility or reproductive performance in rodents had been adequately characterized (9, 10), but the threshold for fetal effects had not been defined. Little information was available for effects in animals following dermal exposure to TCE.
In summary, the TCE Subregistry was created in response to the pervasiveness of TCE in the nation's waste sites; the relative lack of information on human health outcomes associated with long-term, low-level exposure to TCE; and the knowledge of adverse health outcomes among people experiencing different types of TCE exposure (for example, short term exposure at high concentrations). Subsequent new knowledge concerning TCE exposure and human health, available since the establishment of the TCE Subregistry, further supports the maintenance of a TCE Subregistry.
TCE SITES: SELECTION AND DESCRIPTION
The site selection process used for developing subregistries in the National Exposure Registry is described in detail in the NER Policies and Procedures Manual (1).
During the site selection process, a total of 279 potential sites were identified as having TCE as a contaminant of drinking water. After reviewing the sites with respect to certain criteria, the sites described in this section were selected as the most appropriate candidates for inclusion in the TCE Subregistry. The criteria for selection included documentation of drinking water contamination and level(s) of contamination, identification of and estimated size of the exposed population, identification of any existing potential exposure or past potential exposure (including duration of exposure and the time elapsed since exposure), identification of susceptible subpopulations, identification of any existing biomonitoring data, identification of the number and levels of secondary contaminants, and confirmation of documented individual exposures. Also, sites where state and local officials supported development of a subregistry were given priority.
A total of 13 sites located in three states were initially selected for inclusion in the TCE Subregistry. Two sites in two states were subsequently added at later dates. The exposure period for each of these sites represents estimated beginning dates and confirmed ending dates of contamination. The beginning dates reflect the most appropriate dates based on existing environmental data and other information obtained from local, state, or other federal agencies.
The type, amount, and quality of environmental data varied greatly from site to site. The quantity, number, and source of chemicals released varied considerably across sites. Also, the local soil and weather conditions very likely affected the environmental measurement and sampling schemes and added to the variations from site to site1.
Table 2-2 provides the name2 and location of each site. The table also provides a summary of environmental data by site. In most cases, documented contamination for a given household address was based on one environmental sample.
1The contaminant levels and sampling dates might also vary within a site when households or residences are compared, especially if they are served by individual wells. For this and other reasons (for example, variations in well construction and depth), the range in TCE sampling results within sites might be great.
2The Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (11), amended by the Superfund Amendments and Reauthorization Act of 1986 (12), provides for recovery of costs incurred for registries from the responsible party(ies). ATSDR assigns unique names and identification numbers to all Superfund sites; tracks the costs incurred by ATSDR, both direct and indirect, for those sites; and prepares cost recovery packages.
Table 2-2.—Summary of environmental data by site.
TCE Subregistry Site |
Year |
Exposure |
Level of TCE |
|
Maximum |
Median |
|||
Michigan |
||||
| Verona Well Field Dowagiac |
1970 |
13.0 |
2,000 |
6.0 |
| McGraw-Edison Corporation | 1975 |
7.0 |
733 |
1.0 |
Indiana |
||||
| Superior Street (Elkhart) | 1976 |
11.0 |
19,380 |
84.0 |
| Central Area (Elkhart) | 1980 |
7.0 |
114 |
0.4 |
| Gemeinhardt Company Inc. | 1972 |
17.0 |
1,600 |
4.0 |
| Conrail Rail Yard | 1970 |
18.0 |
1,520 |
78.0 |
Illinois |
||||
| Acme Solvents Reclamation, Inc. | 1980 |
10.5 |
100 |
1.0 |
| Beloit Corporation | 1983 |
7.5 |
3 |
2.0 |
| Byron Johnson Salvage Yard | 1980 |
10.5 |
249 |
9.1 |
| Frinks Industrial Wastes | 1978 |
12.5 |
16 |
14.0 |
| Southeast Rockford Groundwater Contamination |
1978 |
12.5 |
122 |
15.0 |
| Warner Electric Brake and Clutch Company |
1978 |
6.5 |
5,220 |
234.0 |
Pennsylvania |
||||
| Crossley Farm | 1967 |
20.0 |
24,000 |
53.6 |
Arizona |
||||
| Tucson International Airport Area | 1951 |
33.0 |
409 |
8.8 |
*Exposure period is based on best available evidence of when contamination occurred and when exposure ceased following water treatment or switch to an alternative water source.
† ppb = parts per billion .
The following summaries of the 15 sites included in the TCE Subregistry present a brief description of the source of contamination, the time period of documented contamination, and specific contaminants detected in sampling activities.
DESCRIPTION OF TCE SUBREGISTRY SITES
Michigan
Verona Well Field Area
Verona Well Field (see Figure 1, Appendix A) supplied potable water to the 35,000 residents of Battle Creek, Michigan. Contamination in the area was first documented in August 1981, when water samples collected from a local church revealed volatile organic compound (VOC) contamination. Subsequent sampling of the municipal wells by the Michigan Department of Public Health indicated that 10 of the 28 wells in the field were also contaminated with VOCs. Private water supply wells located in residential areas around the well field were also found to be contaminated. The contaminated municipal well field was listed by the U.S. Environmental Protection Agency (EPA) as a National Priority List (NPL) site in July 1982. In 1983, an EPA remedial investigation identified the primary sources of contamination.
By the end of 1982, 81 of the 142 private wells tested were found to be contaminated according to ATSDR records. The maximum contaminant concentrations in the private wells (see Table 2-3) were much greater than the concentrations in the public water supply. The public water supply was subject to a blending process that lowered the concentration of contamination below the EPA maximum contaminant limit (MCL) of 5 parts per billion (ppb) for drinking water (6). Only those residences using private well water were included in the Battle Creek Epidemiology Study (13) and subsequently, the TCE Subregistry.
Verona registrants were selected to participate in the TCE Subregistry based on their eligibility for inclusion in the 1986 Battle Creek health study (13). All participants associated with the 1986 Battle Creek health study3 (both the exposed and comparison populations) were asked to take part in the National Exposure Registry. The Battle Creek health study, supported by ATSDR, was conducted by the Centers for Disease Control and Prevention (CDC) in conjunction with the Michigan Department of Public Health. The study included VOC-exposed and comparison (very low or no exposure) participants. People who were eligible but had declined to participate in the health study were asked to participate in the TCE Subregistry; 72 people chose to participate. The comparison population from the epidemiology study was not included in the analysis presented in this report.
3The Battle Creek health study was a retrospective cohort study that included two groups: a cohort of people exposed to VOCs and a reference cohort of people who had very low exposure or were unexposed (13). The exposed cohort included current and former residents of homes with contaminated wells in the areas known as Verona Park, Springfield, and Dowagiac.
Table 2-3.—Verona Well Field and Dowagiac, Michigan, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 77 |
0.01 |
2,000 |
6.0 |
| (cis)-1,2,-Dichloroethene | 70 |
ND†† |
3,900 |
6.0 |
| 1,1-Dichloroethane | 59 |
ND |
150 |
2.0 |
| Tetrachloroethylene | 57 |
ND |
230 |
1.0 |
| 1,1,1-Trichloroethane | 55 |
ND |
134 |
3.0 |
| 1,2-Dichloroethane | 51 |
ND |
325 |
3.0 |
| 1,1-Dichloroethene | 51 |
ND |
60 |
1.0 |
| (trans)-1,2-Dichloroethane | 16 |
ND |
1 |
ND |
| Freon | 5 |
ND |
<0.01 |
ND |
| Methylene chloride | 4 |
ND |
3 |
1.5 |
| Chloroform | 3 |
ND |
<0.01 |
ND |
Specific chemical names and table values reported to the 10th or 100th decimal place are values provided to ATSDR.
Note: The Verona Well Field and Dowagiac data were combined here, and elsewhere throughout this reported, for two reasons. First, all registrants associated with these two sites were derived from a listing of participants and nonparticipants of the Battle Creek health study (13). The researchers for that study did not distinguish cases according to site area. Second, the Verona Well Field and Dowagiac sites share the same cost recovery identification number.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn> .
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods .
The beginning exposure date was estimated to be 1970, about 1.5 years after the solvent company identified by EPA as the source of the contamination started its operations. This date was considered to represent the minimum length of time necessary for the contamination to have occurred and for the VOCs to have reached the wells at a detectable level. Most residents with contaminated private wells were changed to a VOC-free water source between 1982 and 1983.
Dowagiac
In 1983, VOCs were discovered in private residential wells in Dowagiac, Michigan, located in Cass County approximately 70 miles southwest of Battle Creek (Figure 2, Appendix A). The source of contamination appeared to be an industrial plant that used solvents to degrease manufactured metal parts. The solvents were stored in underground tanks that are believed to have leaked. Such solvents had been stored in the tanks for decades. Evaluation of the existing environmental data indicated that contamination in Dowagiac started many years before 1977.
The contaminants reported in residential wells are shown in Table 2-3. The exposure period considered for the TCE Subregistry was from January 1, 1975, through December 31, 1981.
McGraw-Edison Corporation
The McGraw-Edison Corporation plant of Albion, Michigan (Figure 3, Appendix A), manufactured air conditioners, humidifiers, dehumidifiers, electric heaters, and air cleaners from 1958 through 1980. From 1970 through 1980, TCE-contaminated industrial distillate (still bottoms) was spread over a dirt road and the parking lots adjacent to the plant to control dust. Based on existing environmental information, it is estimated that 15,000 gallons of contaminated still bottoms was spread on site. Analysis of the on-site residue revealed TCE concentrations as high as 27,000 parts per million (ppm).
Two distinct aquifers lie below the McGraw-Edison plant in unconsolidated glacial sediments containing a sandy unit interspersed with layers of gravel, coal, and silt, and a discontinuous clay layer. The upper aquifer varies in thickness from 1 to 50 feet. The lower aquifer lies 10 to 75 feet below the ground surface and is a minimum of 290 feet thick. The general direction of groundwater flow is south-southwest.
From 1980 to 1981, TCE was found in on-site shallow monitoring wells at a maximum level of 946,937 ppb, and in on-site deep wells at 8,590 ppb. At the time of off-site sampling, the contaminant plume had migrated approximately 0.5 mile. The nearest residence was 0.2 mile away. TCE was the only contaminant detected in most of the well samples (see Table 2-4). Concentrations of TCE as high as 733 ppb were detected in private residential wells.
People with contaminated private wells were initially supplied with bottled water and were later connected to the municipal water system. The period of exposure for subregistry purposes was determined to be from January 1, 1975, through December 31, 1981.
Table 2-4.—McGraw-Edison Corporation, Michigan, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 135 |
ND†† |
733 |
1.0 |
| Chloroform | 4 |
1 |
3 |
2.5 |
| (cis)-1,2-Dichloroethene | 4 |
5 |
18 |
5.5 |
| 1,2-Dichloroethane | 1 |
9 |
9 |
9 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn.
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
Indiana
Superior Street
The Superior Street site is located on the east side of Elkhart and includes the East Jackson Street neighborhood (Figure 4, Appendix A). According to Elkhart County Health Department records, TCE contamination was first documented from samples taken in 1976 in response to citizen complaints. However, the results of the sample analyses were not available for review. The timing of the complaints corresponded with a January 1976 fire at an underground storage tank facility south of Superior Street.
Residential well sampling was again conducted in 1985 and revealed TCE contamination; the results of this sampling are presented in Table 2-5. After the 1985 groundwater investigation, further testing was conducted in adjacent areas (see other Elkhart sites reported in the sections that follow) to identify the range of the contamination. After 1986, either an alternative water supply or installation of a filtration system was provided for residences using contaminated water. The exposure period was from January 1, 1976, through December 31, 1986.
Table 2-5.—Superior Street, Elkhart, Indiana, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 146 |
0.06 |
19,380 |
84.0 |
| Tetrachloroethylene | 77 |
ND†† |
140 |
ND |
| 1,1-Dichloroethene | 74 |
ND |
1,260 |
1.0 |
| 1,1,1-Trichloroethane | 51 |
ND |
2,200 |
2.0 |
| Trichlorofluoromethane | 16 |
ND |
340 |
1.0 |
| 1,1-Dichloroethane | 15 |
ND |
1,120 |
1.0 |
| 1,2-Dichloroethane | 14 |
ND |
54 |
1.0 |
| 1,2-Dichloropropane | 14 |
ND |
40 |
1.0 |
| Benzene | 9 |
2.99 |
7.5 |
4.5 |
| Vinyl chloride | 5 |
ND |
60 |
2.5 |
| Bromodichloromethane | 4 |
ND |
0.7 |
0.1 |
| Chloroethane | 4 |
ND |
5.7 |
ND |
| Chloroform | 4 |
ND |
460 |
26.6 |
| Methylene chloride | 4 |
ND |
21.2 |
0.5 |
| (cis)-1,2,-Dichloroethene | 1 |
9 |
9 |
9 |
| 1,2-Dichloroethylene | 1 |
9 |
9 |
9 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn .
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
Central Area
The Central Area (Figure 5, Appendix A) includes central Elkhart south of the St. Joseph River and east to the Elkhart River, and extends south of the city. There are several possible contaminant sources (many leaking underground storage tanks) throughout this area of the city.
TCE contamination was first noticed in 1983, by residents complaining of a strong odor in their water. According to Elkhart County Health Department files, in 1983 the first samples from residential wells were taken; they revealed TCE and other chemical contamination (Table 2-6). Letters were issued to residents with contaminated wells warning them of the problem. Private well sampling repeated by EPA in 1985 showed migration of the contamination to other residences in the vicinity. At that point, Superfund expenditures were approved to provide bottled water and access to city water for the affected residents.
For purposes of the TCE Subregistry, the exposure period was determined to be from January 1, 1980, through December 31, 1986, when residences were put on an alternative water supply or filtration systems were installed.
Gemeinhardt Company Inc.
The Gemeinhardt Company Inc. is located in the southwestern corner of the city of Elkhart (Figure 6, Appendix A). Gemeinhardt has manufactured flutes and piccolos on the site since the 1940s. TCE was used in the process until 1972. From 1972 through 1980, 1,1,1-trichloroethane was used. Tetrachloroethylene has been used since 1980.
A groundwater problem was first recognized by a Gemeinhardt employee who complained to the Elkhart County Health Department about the water quality at the plant. Sampling was conducted by the health department in September 1983, and revealed residential well contamination (Table 2-7). Contaminated soil was removed from an on-site seepage bed and two dry wells in the fall of 1984.
The contaminant migration was to the north-northwest, with an increase in concentration approximately 2,000 feet from the site. The center of the TCE plume was approximately 1,600 feet to the north-northwest, in the vicinity of another musical instrument manufacturing company using some of the same solvents. The exposure period for TCE Subregistry purposes was from January 1, 1972, through December 31, 1988, when the residences were supplied with an alternative water source or filtration systems were installed.
Conrail Rail Yard
This 675-acre site is owned by the Consolidated Rail Corporation and is situated in the southwest corner of the city of Elkhart, Indiana (Figure 7, Appendix A). At the time of data collection, the site contained 72 rail tracks where cars were electronically separated and switched from one track to another. The yard handled approximately 75 trains per day. Car repair and diesel refueling were also conducted on the site. The Conrail facility has been in operation since about 1956, and was extensively renovated during the period 1979 through 1982. Adjacent to the site are
Table 2-6.—Central Area, Elkhart, Indiana, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 28 |
<0.10 |
114 |
0.4 |
| Tetrachloroethylene | 26 |
ND†† |
105 |
ND |
| 1,1-Dichloroethene | 25 |
ND |
92.1 |
ND |
| 1,1,1-Trichloroethane | 22 |
ND |
0.7 |
ND |
| 1,2-Dichloropropane | 2 |
3 |
3 |
3 |
| Vinyl chloride | 2 |
15 |
22.2 |
18.6 |
| (cis)-1,2,-Dichloroethene | 1 |
240 |
240 |
240 |
| 1,1-Dichloroethane | 1 |
4 |
4 |
4 |
| 1,2-Dichloroethylene | 1 |
1.7 |
1.7 |
1.7 |
| Toluene | 1 |
0.2 |
0.2 |
0.2 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn.
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
light industrial operations; a residential area on County Road Number 1 is located about 2,000 feet beyond the outlying light industrial areas.
The aquifer in this area is located in fairly coarse, highly permeable glacial outwash. The groundwater flow is northwest, toward the St. Joseph River. Information available about the contaminant plume indicated it was 1.5–2.0 miles long and discharged into the St. Joseph River. The groundwater flow rate was calculated to be 0.43 foot per day.
The Elkhart County Health Department requested an investigation by EPA in 1986 to confirm indications that local wells were contaminated with carbon tetrachloride and TCE. Five areas on site were identified as potential sources of the contamination. Residential wells downgradient from these sites were affected by the contaminant plume (Table 2-8).
Table 2-7.—Gemeinhardt Company, Inc., Elkhart, Indiana, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 121 |
ND†† |
1,600 |
4.0 |
| 1,1,1-Trichloroethane | 112 |
ND |
7,100 |
18.2 |
| 1,1-Dichloroethane | 100 |
ND |
160 |
1.5 |
| Tetrachlorethylene | 68 |
ND |
7,500 |
ND |
| 1,1-Dichloroethane | 49 |
ND |
160 |
6.0 |
| Carbon tetrachloride | 23 |
ND |
39 |
ND |
| (trans)-1,2,-Dichloroethene | 23 |
ND |
40 |
5.0 |
| Methylene chloride | 11 |
19.90 |
11,000 |
20.0 |
| Chloromethane | 10 |
9.99 |
180 |
11.5 |
| Chloroform | 4 |
ND |
0.5 |
0.4 |
| Toluene | 3 |
0.20 |
6.8 |
1.3 |
| (cis)-1,2-Dichloroethene | 2 |
3.20 |
7.1 |
5.2 |
| Ethyl bezene | 2 |
2.10 |
5.2 |
3.7 |
| Xylene | 2 |
15.50 |
45.2 |
30.4 |
| Chloroethane | 1 |
9.9 |
9.9 |
9.9 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn .
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
Table 2-8.—Conrail Rail Yard, Elkhart, Indiana, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 51 |
<0.10 |
1,520 |
78.0 |
| Carbon tetrachloride | 51 |
ND†† |
6,860 |
48.0 |
| 1,1-Dichloroethene | 51 |
ND |
60 |
ND |
| Tetrachloroethylene | 51 |
ND |
2.4 |
ND |
| Chloroform | 49 |
ND |
75 |
ND |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn.
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
In 1979, the municipal water system in Elkhart provided service for approximately 41,000 persons. The remaining population obtained its water from private residential wells. One hundred houses using private wells were located north (downgradient) of the site. Since 1987, 76 of the houses with contaminated wells have used whole-house water filters or point-of-use water filters. The remaining 24 houses have been supplied with bottled water.
Using the groundwater flow rate, ATSDR estimated that the period of exposure was from January 1, 1970, until December 31, 1987. Carbon filtration systems were installed after 1987.
Illinois
Acme Solvents Reclamation, Inc.
The Acme Solvents Reclamation facility is located in a low-density residential area of Winnebago County in northern Illinois (Figure 8, Appendix A). The 20-acre facility was active from 1960 through 1973. Still-bottom residues, sludge, nonrecoverable solvents, paints, and oils were disposed of on site in unlined lagoons or stockpiles. Adjacent to the site were other potential sources for groundwater contamination, including an asphalt-lined sanitary landfill to the west and a mixing plant and quarry to the northeast. Two aquifers are located in the Acme site area; one aquifer is in the unconsolidated deposits (loose material) which overlie the area, the other is in the bedrock material. The groundwater flow is from east to west.
In 1981, the Illinois Environmental Protection Agency detected chemicals from the Acme site in nearby residential wells (Table 2-9). The exposure period for TCE Subregistry purposes was from January 1, 1980, through June 2, 1990, when baseline data collection for the TCE Subregistry began. The United States EPA supplied carbon-filtration systems to the residences with contaminated wells in 1990 as part of the remediation efforts.
Beloit Corporation
The Beloit Corporation (Figure 9, Appendix A) manufactures equipment for the pulp and paper industry, and is located on 175 acres along the Rock River north of the city of Rockton, Illinois. Prior to 1986, wastes from its manufacturing and equipment demonstration processes were disposed of in three unlined lagoons located at the northern end of the site near the Rock River. Since 1986, the wastes have been treated in a process waste water treatment system. In 1981, sediments from the lagoons were injected into the subsurface soil at the southern boundary of the site. Approximately 220,000 gallons of sludge were injected into a 10-acre site. On-site groundwater monitoring has been conducted since 1982 by the Beloit Corporation as part of its groundwater compliance monitoring program. Available sampling results from the on-site monitoring showed TCE contamination of up to 42 ppb.
The predominant flow of groundwater is to the south-southwest. Approximately 300 houses were within a 1-mile radius of the facility. All 65 houses in the Blackhawk subdivision, located about 600 feet southeast of the site, used private wells for their water source. Of the 65 private wells, 55 have been sampled by EPA since 1982. Sixteen wells were found to be contaminated with VOCs and three of the sixteen had TCE contamination (Table 2-10). In addition, Rockton municipal well Number 5 is located one-half mile southeast of the site. Although the municipal well was sampled, contamination was not detected. The estimated exposure period was January 1, 1983, through June 2, 1990, when TCE Subregistry data collection began.
Byron Johnson Salvage Yard
The Byron Johnson Salvage Yard is located in a rural area of Ogle County in northern Illinois, between the cities of Byron and Oregon. In 1990, the population within 1.5 miles of the site was estimated to be 500 to 1,000 people, with the majority living west, northwest, and north of the site. The site (Figure 10, Appendix A) consists of two areas: the 20-acre Byron Johnson Salvage Yard, and the 480-acre former Dirk's Farm property. Waste materials containing VOCs, cyanide, and heavy metals had been improperly disposed of during the 1960s and 1970s in both areas, resulting in contamination of soil or sediment and groundwater. Investigation of the site was initiated by EPA in 1970, when a strong chemical odor and soil discoloration in puddles were noticed throughout the salvage yard. Available data from groundwater monitoring wells in the area indicated that both the upper aquifer (Galena-Plateville Dolomite) and lower aquifer (St. Peter Sandstone) were contaminated with VOCs, heavy metals, and cyanide. The plume extended at least 1.5 miles to the
Table 2-9.—Acme Solvents Reclamation, Inc., Illinois, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 49 |
ND†† |
100 |
1.0 |
| Tetrachloroethylene | 17 |
ND |
86 |
3.0 |
| 1,1-Dichloroethane | 16 |
ND |
38 |
4.4 |
| Methylene chloride | 16 |
ND |
22 |
ND |
| 1,1,1-Trichloroethane | 14 |
ND |
8 |
1.5 |
| Bromodichloromethane | 13 |
ND |
20 |
ND |
| Carbon tetrachloride | 13 |
ND |
30 |
ND |
| (trans)-1,2,-Dichloroethane | 13 |
ND |
200 |
8.0 |
| Butyl benzyl phthalate | 12 |
ND |
15.6 |
ND |
| Bis (2-ethylhexyl) phthalate | 12 |
ND |
56.8 |
ND |
| (trans)-1,3-Dichloropropane | 12 |
ND |
15.6 |
ND |
| 1,2-Dichloroethane | 4 |
ND |
4.99 |
0.5 |
| Copper | 3 |
10 |
20 |
10.0 |
| Iron | 3 |
ND |
100 |
ND |
| Magnesium | 3 |
41,000 |
104,000 |
54,100.0 |
| Manganese | 3 |
ND |
50 |
20.0 |
| Zinc | 3 |
ND |
100 |
ND |
| Bromoform | 1 |
0.99 |
0.99 |
0.99 |
| Chloroform | 1 |
0.99 |
0.99 |
0.99 |
| Dibromochloromethane | 1 |
0.99 |
0.99 |
0.99 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn.
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn .
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
Table 2-10.—Beloit Corporation, Illinois, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 5 |
1 |
3 |
2.0 |
| 1,1,1-Trichloroethane | 5 |
1 |
212 |
27.0 |
| Methylene chloride | 4 |
1 |
1 |
1.0 |
| 1,1-Dichloroethene | 3 |
7 |
17 |
7.0 |
| Tetrachloroethylene | 3 |
45 |
300 |
48.0 |
| 1,1-Dichloroethane | 2 |
1 |
2 |
1.5 |
| Bromoform | 1 |
1 |
1 |
1 |
| Dibromochloromethane | 1 |
1 |
1 |
1 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn .
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn .
northwest and 0.5 mile to the west and north, and affected the water quality of residential wells (Table 2-11).
In July 1984, households using water contaminated with greater than 200 ppb TCE were supplied with bottled water, however, residents continued to use contaminated water for other household purposes. For TCE Subregistry purposes, the exposure period was from January 1, 1980, through June 2, 1990, when baseline data collection began.
Frinks Industrial Waste
Frinks Industrial Waste, a 4.8-acre site located 2 miles north of Pecatonica, Illinois (Figure 11, Appendix A), began operation under a state-issued permit in 1979 as a septic tank pumping service. In 1980, the business was expanded to include handling and treatment of industrial wastes. A lagoon for storing wastes was constructed in 1975 and closed in 1980. The wastes included oils, cyanide-containing compounds, solvents, and alkaline- and acid-containing wastes. Disposal methods consisted mainly of gravity separation and disposal in unlined lagoons.
Table 2-11.—Byron Johnson Salvage Yard, Illinois, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 33 |
0.90 |
249 |
9.1 |
| Tetrachloroethylene | 32 |
ND†† |
8 |
0.1 |
| (trans)-1,2-Dichloroethane | 22 |
ND |
12 |
ND |
| 1,1,1-Trichloroethane | 18 |
ND |
21 |
9.5 |
| Carbon tetrachloride | 7 |
1 |
4 |
3.0 |
| 1,1-Dichloroethane | 7 |
3 |
20 |
7.0 |
| 1,1-Dichloroethene | 4 |
2 |
6 |
4.0 |
| Other volatile organic compounds | 3 |
ND |
18 |
16.0 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn .
§ ppb = parts per billion .
¶ These values represent the maximum reading reported from N samples drawn .
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
Groundwater is present at the facility in both the overlying unconsolidated (loose) till and the underlying bedrock. The aquifer most used as a domestic water supply source in the area is in the upper bedrock formation (Galena-Plateville Dolomite). This aquifer occurs at depths ranging from 20 to 60 feet. The primary direction of groundwater flow in the aquifer is to the south at 15.0 feet per year. Contamination has migrated off site to nearby residential wells (see Table 2-12). This area was rural, therefore, few wells were affected. The period of exposure for TCE Subregistry purposes was from January 1, 1978, through June 2, 1990, when TCE Subregistry data collection began.
Southeast Rockford Groundwater Contamination
The Southeast Rockford site (Figure 12, Appendix A) is located in a 2-square-mile residential area. Groundwater contamination in the area was first identified by EPA in 1984 during an investigation of illegal dumping by an electroplating company. In 1984, an investigation by the Winnebago County Health Department revealed a contaminant plume extending for 2 miles from 20th Street to
Table 2-12.—Frinks Industrial Waste, Illinois, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 5 |
5 |
16 |
14.0 |
| 1,1,1-Trichloroethane | 4 |
1 |
2 |
2.0 |
| Other volatile organic compounds | 1 |
4 |
4 |
4 |
| (trans)-1,2-Dichloroethene | 1 |
12 |
12 |
12 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn.
§ ppb = parts per billion .
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn .
the Rock River. The plume is believed to have originated from multiple sources. The principal direction of the groundwater movement in southeast Rockford is from the uplands on the east to the Rock River on the west.
Although municipal water was available, many residents of the Rockford site used private wells. Samples taken in 1984 from houses with shallow wells (50 feet or less) in the sand and gravel aquifer showed elevated levels of VOC contamination (Table 2-13). Rockford municipal well Number 35, located in this area, was drilled much deeper (150 feet) in the sand and gravel aquifer and also had elevated VOC levels. Well Number 35 was closed in 1985 because of this contamination. The period of exposure for TCE Subregistry purposes was January 1, 1978, through June 2, 1990, when baseline data collection began.
Warner Electric Brake and Clutch Company
Warner Electric Brake and Clutch Company (Figure 13, Appendix A) is a manufacturing facility located on 93.3 acres in Roscoe, Illinois (population 1,600). The facility has been in operation since 1957. In the brake, clutch, and drive train component manufacturing process, various organic solvents are used for degreasing and parts cleaning. Two on-site, unlined lagoons were used to dispose of waste solvents as part of the facility's National Pollution Discharge and Elimination System (an EPA program).
Sandy, gravely soils and a shallow aquifer make the groundwater highly susceptible to contamination. Available environmental information indicated that a well-defined contaminant plume
Table 2-13.—Southeast Rockford Groundwater Contamination, Illinois, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 390 |
0.45 |
122 |
15.0 |
| 1,1,1-Trichloroethane | 369 |
ND†† |
436 |
41.0 |
| 1,1-Dichloroethane | 331 |
ND |
133 |
11.0 |
| (trans)-1,2-Dichloroethane | 227 |
ND |
100 |
ND |
| Tetrachloroethylene | 226 |
ND |
32 |
ND |
| 1,1-Dichloroethene | 219 |
ND |
236 |
4.0 |
| 1,2-Dichloroethane | 148 |
ND |
52 |
ND |
| (cis)-1,2-Dichloroethene | 112 |
ND |
456 |
7.5 |
| Chloroform | 57 |
ND |
140 |
ND |
| Methylene chloride | 16 |
ND |
9 |
ND |
| Bromodichloromethane | 2 |
1.50 |
3.7 |
2.6 |
| Benzene | 1 |
6.5 |
6.5 |
6.5 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn .
§ ppb = parts per billion .
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
approximately 5,000 to 7,200 feet long and 12,000 feet wide originated from the unlined lagoons. Groundwater in the vicinity of the plume flows from the north and northeast to the south and southwest toward the Rock River.
The Town of Roscoe, Illinois, does not have a public water supply, so all houses rely on private wells. Two subdivisions comprising 300 houses are located adjacent to the site (Figure 14, Appendix A). The contaminant plume is located directly underneath the two subdivisions. In early 1983, concentrations of TCE exceeding 500 ppb were found by the Winnebago County Public Health Department in the residential wells of 30 houses. Subsequent investigations by the Illinois Department of Public Health revealed about 100 residences with TCE-contaminated wells (Table 2-14). In December 1983, Warner began supplying all residents of the two subdivisions with bottled water. For TCE Subregistry purposes, the exposure period was from January 1, 1978-July 31, 1984.
Table 2-14.—Warner Electric Brake and Clutch Company, Roscoe, Illinois, residential well sampling.
Chemical |
N* |
|
|
|
| Trichloroethylene | 108 |
0.50 |
5,220 |
234.0 |
| 1,1,1-Trichloroethane | 105 |
ND†† |
255 |
10.0 |
| Tetrachloroethylene | 100 |
ND |
45 |
1.0 |
| 1,1-Dichloroethane | 4 |
ND |
8 |
3.7 |
| Methylene chloride | 2 |
1 |
3 |
2.0 |
| Other volatile organic compounds | 2 |
ND |
2 |
1.0 |
| (trans)-1,2-Dichloroethene | 2 |
ND |
1 |
0.5 |
| (cis-1,2,-Dichloroethene | 1 |
6 |
6 |
6 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn .
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
Pennsylvania
Crossley Farm/Hereford Groundwater Site
In November 1983 elevated levels TCE were discovered at the Crossley Farm Site (Figure 16, Appendix A), approximately 65 miles northeast of Philadelphia, Pennsylvania, after citizens complained that their drinking water was of poor quality. In September 1986, in response to more citizen complaints, further testing was done, which detected TCE concentrations ranging from 500 to 19,000 ppb in tap water samples collected from residences (Table 2-15). Carbon filtration systems were installed in homes with elevated levels.
Table 2-15—Crossley Farm/Hereford Groundwater Site, Pennsylvania, residential well sampling.
Chemical |
N* |
|
|
|
| TCE | 62 | 2 | 24,000 | 53.6 |
| Acetone | 4 | ND | 0.6 | 0.6 |
| 1,1,1-Trichloroethane | 1 | 1.27 | 1.27 | 1.27 |
| 1,2-Dichloroethylene | 17 | ND | 90 | ND |
| Chloroform | 1 | 3.14 | 3.14 | 3.14 |
| Methylene chloride | 34 | ND | 1900 | ND |
| Tetrachloroethylene | 44 | ND | 343 | ND |
| trans 1,2-Dichloropropane | 1 | 0.73 | 0.73 | 0.73 |
| Trichlorofluoromethane | 10 | ND | 50 | ND |
Specific chemical names and table values reported to the 10th or 100th decimal place are values that were provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn.
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods .
The source of the contamination was determined to be an abandoned quarry on the Crossley Farm. Illegal waste disposal activity reportedly occurred at the site from the mid-1960s to the mid-1970s. Drums containing mostly liquid wastes from Bally Case and Cooler were disposed at the quarry. Several of the drums had a characteristic solvent odor. As many as 300 drums (possibly more) from Bally Case and Cooler were disposed at Crossley Farm, with activity reaching a peak in 1971.
The Hereford Township was estimated to have a population of 3,016 in 1984. Approximately 23 houses were affected by the contaminant plume and so current and prior residents are eligible for the TCE Subregistry. The period of exposure was January 1967 until filtration systems were installed, which took place between 1983 and 1987.
Arizona
Tucson International Airport Area
The Tucson International Airport Area (TIAA) Superfund site occupies approximately 24 square miles in the southwestern section of Tucson, Pima County, Arizona. It includes the Tucson International Airport, portions of the San Xavier Indian Reservation, residential areas of the City of Tucson and the City of South Tucson, and Air Force Plant Number 44/Hughes Aircraft Company Facility.
Past disposal practices of hazardous waste at the TIAA Superfund site have resulted in groundwater contamination of the regional aquifer. Hughes Aircraft is a primary contributor to the groundwater contamination, which consists of a TCE plume that has migrated to the northwest, crossing the San Xavier Indian Reservation, into residential areas of Tucson where many city and private wells are located.
In the early 1980s, city and private wells in which TCE was detected above the MCL were abandoned. Table 2-16 lists the contamination levels measured in public or private wells affected by the contaminant plume.
Since 1981, the City of Tucson has monitored municipal wells for TCE. Municipal wells are removed from service when TCE levels exceed 5 ppb. As of October 1987, nine municipal wells had been removed from service; one was returned to service following construction of a tower to remove volatile organic compounds, including TCE. Water from multiple wells was mixed during distribution, making it difficult to measure contamination levels. In addition, water from some wells was pumped to an open reservoir where off-gassing occurred.
In order to meet the eligibility criteria of documented exposure for more than 30 days, only those Tucson residents using private wells that had analytical data documenting contamination with TCE were eligible to be enrolled in the TCE Subregistry. A total of 14 wells serving approximately 100 individuals met the criteria. For the purpose of the TCE Subregistry, the period of exposure is estimated to be from 1951, until wells were removed from service, between 1984 and 1987.
Table 2-16.—Tucson International Airport, Tucson, Arizona, (public and private) well sampling.
Chemical |
N*/P> |
|
|
|
| Trichloroethylene | 184 |
<0.3 | 409.0 | 8.8 |
| 1,1,1-Trichloroethane | 4 |
<0.4 | <4.9 | <0.5 |
| 1,1-Dichloroethane | 6 |
<0.4 | <4.7 | 0.7 |
| 1,1-Dichloroethylene | 26 |
ND | 31.0 | 1.1 |
| Trans-1,2-dichloroethylene | 17 |
ND | 13.0 | 2.0 |
| 1,2-Dichloropropane | 3 |
<0.4 | <2.6 | 0.9 |
| Bis-2-ethylhexyl phthalate | 2 |
31.0 | 53.1 | 44.1 |
| Carbon tetrachloride | 6 |
<0.4 | <4.9 | 0.7 |
| Chloroform | 21 |
ND | 40.0 | >4.4 |
| Chromium | 24 |
<10.0 | 37.0 | <10.0 |
| Di-n-butyl phthalate | 1 |
87.8 | 87.8 | 87.8 |
| Isophorone | 1 |
9.0 | 9.0 | 9.0 |
| Methylene chloride | 2 |
<0.5 | <4.8 | 2.7 |
| Tetrachloroethylene | 3 |
<5.1 | <5.3 | <5.1 |
| Trichlorofluoromethane | 1 |
<0.7 | <0.7 | <0.7 |
Specific chemical names and table values reported to the 10th or 100th decimal place are values provided to ATSDR.
* N is the number of samples with reported results for the particular chemical.
† These values represent the minimum reading reported from N samples drawn.
§ ppb = parts per billion.
¶ These values represent the maximum reading reported from N samples drawn.
** These values represent the median reading reported from N samples drawn.
†† ND means nondetectable using available analytical methods.
Agency for Toxic Substances and Disease Registry, 1825 Century Blvd, Atlanta, GA 30345
Contact CDC: 800-232-4636 / TTY: 888-232-6348
