Water Health Assessment
(Dover Township) Toms River, New Jersey
Draft for Public Comment -- November 16, 1999
The following are quotes of the public comment release of the health assessment on the Toms River area water. Please also read the full report.
1. "However, samples of certain wells at the Parkway well field and parts of the LTWTR distribution system, taken in March and April 1996, were found to contain low levels of trichloroethylene (TCE) and a previously unidentified substance later determined to be styrene-acrylonitrile (SAN) trimer."
2. These contaminants are attributable to the Reich Farm hazardous waste site (CERCLIS #NJD980529713). Two of the Parkway wells (#26 and #28) had been treated by packed tower aeration since 1988 to remove TCE, but a third well (#29) showed sporadic contamination with TCE during this testing period.
3. At present, the public health implications of past SAN trimer contamination cannot be determined since very little is known about its toxicological properties. The NJDHSS, NJDEP and ATSDR support a program of toxicological testing, including the potential for carcinogenicity, currently being developed and coordinated by the U.S. Environmental Protection Agency.
4. In addition to the identification of SAN trimer, the presence of other non-target chemicals in the Reich Farm groundwater plume, and possibly in past samples of the community water supply, is under investigation by a committee coordinated by NJDEP.
5. TCE is classified as a probable human carcinogen based on studies of workers and experimental animals exposed to high levels. While some epidemiologic studies suggest that exposure to TCE in drinking water is possibly related to increased risk of childhood leukemia's, these studies are not conclusive.
6. NJDHSS, NJDEP and ATSDR recommend continued treatment of the Parkway wells affected by the Reich Farm groundwater contamination plume.
7. Gross alpha radiological activity in some points of entry is elevated, particularly those in which a large proportion of water comes from the shallow Kirkwood-Cohansey aquifer.
8. Lead and copper were found in first-draw samples of several of the distribution system (schools) samples, indicating corrosion of metals from building plumbing. Corrosion is a problem common to many water systems and private wells. NJDEP, NJDHSS, and ATSDR recommend routine flushing of taps and water fountains before use to minimize exposure.
9. In the summer of 1987, trichloroethylene (TCE) was detected in the distribution system and traced to the Parkway well field, specifically wells #26, #28 and #29. TCE had also been found in these wells in samples taken in 1986 and 1987 as part of the Remedial Investigation for the Reich Farm Superfund site (NUS, 1986; Ebasco, 1988).
10. The TCE is thought to come from the plume of contaminated groundwater associated with the Reich Farm Superfund site located approximately one mile north of the Parkway well field.
11. Asbestos is now tested for once every nine years in the UWTR system. NJDEP granted UWTR a sampling waiver from this routine test based on the noncorrosive (non-acidic) characteristics of the drinking water (after treatment with lime) in the distribution acidic system. Corrosive (acidic) water has the potential to dissolve the concrete in asbestos cement pipe in the water distribution system, thereby releasing asbestos fibers.
12. Nitrate is tested for once per year at each point of entry. Nitrite is tested for once every three years at each point of entry. All nitrate and nitrite samples taken at UWTR points of entry have been below the allowable limits.
13. Radiological activity is initially assessed by gross alpha and beta activity in samples taken once every four years from the water distribution system, once an initial monitoring period consisting of four quarterly samples has been completed. Historically, radiological results for the UWTR system have been in compliance with radiological activity standards.
14. Two of the wells at the Parkway well field are currently affected by the Reich Farm groundwater contamination plume (and a third well at Parkway is sporadically impacted), but the beginning of the period of contamination is not known with certainty.
15. Shallow wells at the Holly well field were apparently contaminated for a period of time in the mid-1960s with materials from Ciba-Geigy (then known as Toms River Chemical Co.).
16. Volatile Organic Chemicals (Method 524.2) Trichloroethylene (also called TCE) was detected in 11 of 21 distribution (school) drinking water samples from March 28, 1996 at concentrations up to 1.0ug/l
17. TCE was found at 0.9 ug/l in one point of entry sample (Parkway) on April 4, 1996, where it was also detected in three wells (26, 28 and 29) at levels of 5, 8 and 2 ug/l, respectively (Table 6b). The MCL for TCE is 1 ug/l.
18. At the time of sampling, TCE was being removed from wells 26 and 28 through packed tower aeration treatment (also called an air stripper) that was installed in 1988. Since no TCE was detected in the water exiting the air stripper, the TCE in the point of entry sample was most likely attributable to well 29. LTWTR temporarily directed well 29 water through the air stripper in April 1996.
19. As described below in the "Non-target Organic Chemicals" section, the Parkway well field was voluntarily taken off-line by UWTR in November 1996 and returned to service (with wells 26 and 28 being treated and pumped to waste) at the end of May 1997. TCE levels in both wells 26 and 28 have generally ranged between 2 and 6 ug/l from mid-1997 to mid-1999, with levels in well 26 tending lower with time and levels in well 28 tending higher with time (Table 6c).
20. In September and October 1997, traces of TCE (below the method detection limit) were found in well 29 but not at the point of entry. TCE was measured at levels above the method detection limit in well 29 from July to early September 1998, (at less than I ug/1), but was not detectable at the Parkway point of entry in this period. This contamination episode is thought to be related to over-pumping of well 29 relative to wells 26 and 28.
21. The solvents tetrachloroethylene (also called PCE, or perchloroethylene), 1,1,1, trichloroethane (TCA), and 1,2-dichloroethane were also measured at levels up to 2 ug/l in wells 26 and/or 28 in April 1996, but not in the distribution system (school) samples of March 1996. These chemicals were also sporadically reported at lower levels in samples from other shallow Parkway wells. The MCLs for PCE, TCA and 1,2-dichloroethane are 1 ug/l, 30 ug/l and 2 ug/l.
22. TCE and PCE are classified by the International Agency for Research on Cancer (IARC) as probable human carcinogens, based on the weight of evidence from laboratory animal experiments and limited human epidemiologic studies (IARC, 1995). Following long-term, high level exposure, TCE has been shown to produce liver cancer in mice and kidney and testicular tumors in rats (IARC, 1995; ATSDR, 1997a).
23. Chronic, high level PCE exposure produces liver cancer in mice and kidney tumors and mononuclear cell leukemia in rats (IARC, 1995; ATSDR, 1996).
24. Epidemiologic studies of occupationally-exposed workers suggest an association between long-term inhalation exposure to high levels of TCE and increased risk of liver and biliary tract cancer and non-Hodgkin's lymphoma (IARC, 1995; ATSDR, 1997a).
25. Increased risks of esophageal cancer, cervical cancer and non-Hodgkin's lymphoma have been observed in workers exposed to high levels of PCE (IARC, 1995; ATSDR, 1996).
26. TCE and PCE exposure in drinking water has been linked to elevated incidence of cancers in human populations, including leukemia and/or lymphomas in children (MDPH, 1997; Cohn et al., 1994; Lagakos et al., 1984) and to increased risk of adverse developmental effects (Bove et al., 1995; ATSDR, 1997b).
27. Overall, the associations drawn from these limited epidemiologic studies suggest possible risk increases due to exposure to TCE and PCE in drinking water, but are inconclusive. Nonetheless, they do indicate the need for further epidemiologic study (Cantor, 1997).
28. 1,2-Dichloroethane is also classified as a probable human carcinogen (ATSDR, 1994), while there is no evidence to suggest that TCA is carcinogenic (ATSDR, 1995a).
29. Chloroform was also detected at low levels (generally less than 1 or 2 ug/1) with some consistency in some wells, prior to chlorination, indicating that this chemical is present in the aquifer. These wells are: wells 22 and 44 at Parkway, well 32 at South Toms River, well 31 at Route 70, and wells 33, 34 and 35 at Berkeley (Table 6b). According to studies by NJDEP and the USGS, this chemical has previously been detected at low levels elsewhere in the shallow Cohansey aquifer. Although the source or sources are not known with certainty, chloroform in untreated well water may be present due to the common household use of bleach which is discharged to septic tanks and then into groundwater.
30. The safety of THMs and other chemical by-products of disinfection is currently under study. Some of the THMs and other disinfection by-products have been shown to be carcinogenic in laboratory animal studies (IARC, 1991; ATSDR, 1998a; ATSDR, 1991; ATSDR, 1989). Epidemiologic studies of exposure to disinfection by-products indicate that long-term exposure to relatively high levels increases the risk of bladder cancer and possibly rectal cancer (Cantor, 1997; Morris et al., 1992). Recent studies suggest a possible increase in risk of spontaneous abortion or neural tube birth defects from exposure to the relatively high disinfection by-product concentrations found in chlorinated surface water supplies (Swan et al., 1998; Klotz et al., 1998). Federal regulations governing disinfection practices have recently changed to further limit by-product formation while ensuring effective destruction of pathogens.
31. Occasionally, other volatile organic chemicals have been detected within the UWTR system. Well 21 at the Holly well field had low levels of dichlorodifluoromethane (1 to 2 ug/l) on two occasions in 1996 (Table 6b). Xylenes, toluene and/or ethylbenzene were measured (up to 12,ug/l combined) above the detection limits in six of 21 distribution system (school) samples in March 1996, at many of the same sample points where TCE was detected (Table 6a).
32. Ethylbenzene and toluene were measured at trace levels at the Parkway point of entry (but not in any of the component wells) in early April 1996. These compounds are common solvents and are also components of fuel oil and gasoline. MTBE (methyl tertiary-butyl ether), another fuel component and frequent drinking water sample contaminant, has been sporadically detected at low levels (0.3 to 3.0 ug/l) in the Parkway and Route 70 wells and points of entry (Table 6b).
33. MTBE was measured above the detection limit in one school sample (Table 6a), but well below the New Jersey MCL for MTBE of 70 ug/l. Based on animal toxicology studies, MTBE is classified as a possible carcinogen by the USEPA (ATSDR, 1998b).
34. Naphthalene (also measured with one of the semi-volatile methods) was found on two occasions in Berkeley well 34 at a level up to 23 ug/l, and at a trace level in one sample from South Toms River well 38 (Tables 6a and 6b). A trace of naphthalene was also detected in one school (distribution system) sample (Table 6a) . The New Jersey MCL for naphthalene in drinking water is 300 ug/I. The USEPA has determined that there is insufficient information to classify naphthalene as a carcinogen or non-carcinogen (ATSDR, 1995b)
35. Volatile organic chemicals were also found in comparison samples, including typically low levels of THMs (Table 6d). One community supply well also contained trace levels of 1,1,1-trichloroethane, 1,2-dichloroethane and MTBE, each below applicable MCLs.
36. Occasional trace levels of polycyclic aromatic hydrocarbons (PAHS) (for example, fluorene) were found in some well and distribution system (school) samples (Tables 7a and 7b). For the PAHs reported, health based guidance levels range from 300 to 3,000 ug/l.
37. Initial analyses by the NJDEP laboratory, using an analytic method designed for pesticides (USEPA Method 507), indicated the presence of a non-target compound that could not be tentatively identified, particularly in the April 4, 1996 sample from well 26 at the Parkway well field. Subsequent analyses by laboratories of the NJDEP, NJDHSS, USEPA (in Cincinnati, Athens, and Las Vegas) and Union Carbide confirmed the presence of an unknown compound (Richardson et al., 1999). The USEPA Las Vegas laboratory determined the probable structure of the unknown substance, which was consistent with a chemical by-product known to be present in Union Carbide production wastes deposited at the Reich Farm Superfund site in 1971. This substance has been identified as a mixture of isomers of 4-cyano-1,2,3,4-tetrahydro-a-methyl-naphthalene-acetonitrile (THNA) and 4-cyano-1,2,3,4-tetrahydro-1-naphthalene-propionitrile (THNP). Because these closely related compounds are formed as condensation by-products of the styrene-a crylonitrile co-polymerization process and are composed of one part styrene and two parts acrylonitrile, they are collectively referred to as styrene-acrylonitrile (SAN) trimer.
38. The concentration of SAN trimer in Parkway well 26 has ranged between approximately 3 and 5 ug/l, with concentrations tending slightly lower with time (Table 7c). Lesser amounts have been found in wells 28 (approximately 0. 1 ug/1) and, in the summer of 1998, in well 29 (Tables 7b and 7c). The level of trimer is estimated to have been approximately 6 ug/l in well 26 in April 1996, although the analytical method was not designed to quantify the amount present.
39. Diluted levels of trimer were present at the Parkway point of entry and in distribution system (school) sample points (at an estimated level of 1 ug/l or below) in the late March and early April 1996 samples. Based on a detailed review of chromatographs from Parkway well analyses conducted in 1990 by Radian Laboratories for Union Carbide and USEPA, NJDEP staff concluded that SAN trimer was present in samples taken at that time.
40. Upon discovery of SAN trimer in November 1996, the Parkway well field was voluntarily closed by UWTR in response to requests from NJDEP and NJDHSS. A granular activated carbon (GAC) treatment system was designed and constructed for wells 26 and 28 by May 1997. Treated output from these wells is generally discharged to the ground, but may be directed into the distribution system during periods of exceptionally high water demand.
41. In May 1997, the remaining wells in the Parkway well field were restored to service, and the NJDEP and the NJDHSS instituted a program of frequent monitoring of the wells and point of entry. From early July to early September 1998, traces of SAN trimer were detected in well 29 (less than the method detection level of 0. 1 ug/1), but not at the Parkway point of entry. As described above for TCE, this contamination episode is thought to be related to over-pumping of well 29 relative to wells 26 and 28. SAN trimer may also have been present in a well 29 sample in February 1999. UWTR installed additional GAC treatment at the Parkway well field for wells 22 and 29, beginning in June 1999.
42. At the time of its identification in the UWTR system, nothing was known of the toxicity of SAN trimer. Since that time, Union Carbide has sponsored genetic toxicology assays and short-term toxicity testing. This testing revealed that SAN trimer was mutagenic in two of five strains of Salmonella bacteria and that it induced chromosomal aberrations in Chinese hamster ovary cells, but there was no evidence of mutagenicity in two other assays. The lethal single dose was estimated to be 440 and 590 mg/kg in male and female rats. A two-week repeat dosing study showed that daily doses of 300 mg/kg were lethal to rats, while doses of 150 mg/kg resulted in a variety of toxic effects including lethargy, tremors, anemia, and increased liver weight. There was no apparent short-term toxicity at repeated doses of 75 mg/kg. Plans for further toxicological testing are being coordinated by the USEPA and a working group of scientists from the National Institute of Environmental Health Sciences, ATSDR, NJDEP and NJD HSS, with input from Union Carbide and a consultant to the Ocean County Health Department.
43. The NJDEP has formed a committee to evaluate the possible presence of other non- target chemicals, particularly in relation to the Reich Farm groundwater contamination plume. A preliminary evaluation indicates that the following chemicals may be present in the groundwater plume: tetrachlorophdialic anhydride; chlorendic anhydride; chlorostyrene; dichlorostyrene; bis(4-chlorophenyl) sulfone; triallyl isocyanuratc; diphcnylhydrazine picratc or diphenyl amine; N-ethyl- and N-methyl-p-toluenesulfonamide: and SAN dimers. Other possible chemicals are being investigated. The NJDEP committee is expected to issue a report of their findings, separate from this Public Health Consultation. The NJDEP is also carrying out research projects to examine the application of expanded testing methods in other drinking water supplies in the State.
44. In the school distribution system samples in March 1996, "first draw" water samples from seven of the schools reached or exceeded the USEPA Action Level of 20 ug/l for lead (range 20 to 1,930 ug/l). One first draw water sample exceeded the Action Level of 1,300 ug/l for copper (7,130 ug/l). In every case where first draw lead or copper levels were elevated, the corresponding "flushed" level was well below drinking water guidance levels. That is, allowing the water to run through the lines for several minutes resulted in the flushing away of lead and/or copper built up in the water from the building plumbing.
45. Lead can have adverse effects on the neurologic development of children (CDC, 1991). The USEPA has established a drinking water action level for community water supplies of 15 ug/l (based on the 90th percentile of first draw samples taken at representative taps within the system) and a guidance level of 20 ug/l for school drinking water fountains. The action level for copper is based on acute gastrointestinal effects.
46. Barium was detected at some level in all the samples from the distribution system (schools), points of entry and wells, and comparison locations in the approximate range of 10 to 70 ug/l. The MCL for barium is 2,000 ug/l.
47. Mercury was detected in 17 of 21 UWTR distribution system (school) water samples, and in most of the point of entry, well and comparison samples in the range of 0.04 to 0.64 ug/l (Tables 8a, 8b and 8c). However, none exceeded the drinking water MCL of 2 ug/l.
48. Molybdenum was detected in some of the distribution system (school) and comparison samples at levels ranging up to 4 ug/l, and in some of the UWTR points of entry and well samples ranging up to 12 ug/l. Although there is no MCL for this metal, the levels of molybdenum in these samples were below the USEPA lifetime health advisory for molybdenum in drinking water of 40 ug/l.
49. Arsenic, selenium, chromium and cadmium were measured at just above method detection limits in a few well or point of entry samples, in all cases well below MCLs (Table 8b). Chromium was measured at 37 ug/l in one of the comparison wells, a level which is below the MCL of 100 ug/l (Table 8c).
50. (Radiological Activity) However, 13 schools exceeded a gross alpha level of 5 pCi/I (taking into account possible measurement error). This level triggers a regulatory analysis for radium-226 and radium-228. Estimates of combined radium (226 plus 228) activity in these samples were all less than the MCL of 5 pCi/l.
51. The Route 70 and Indian Head points of entry approached or exceeded the combined radium drinking water standard of 5 pCi/I in those and subsequent samples (Table 9b). In response to these findings, UWTR voluntarily reduced use of well #20 at the Indian Head point of entry beginning in the summer of 1996. Measurements from distribution system samples (hydrants) taken 'in July 1996 near the Berkeley and Route 70 points of entry showed relatively high gross alpha and combined radium activity (Table 9a).
52. Radium exposure has been associated with increased risk of bone and paranasal sinus cancers in highly exposed workers (NRC, 1988; NRC, 1990). Few epidemiologic studies have examined the risk of childhood cancers with respect to radium in drinking water. Radium in drinking water has been associated with increased bone cancer incidence in adolescents (Finkelstein and Krieger, 1996) and with leukemia incidence in adults but no children (Lyman et al., 1985). The epidemiologic evidence is insufficient to draw conclusions regarding the risk from radium in drinking water.
53. Uranium activity (for three isotopes: U-238, U-235, and U-234) was measured in April 1996 samples from the Indian Head point of entry and well 20, the Route 70 point of entry and well 3 1, and the Berkeley and Parkway points of entry (Table 9c). Combined uranium ranged from not detectable up to 1.5 pCi/l. Combined thorium activity (for three isotopes: Th-228, Th-230 and Th-232) was measured at 0.2 pCi/I in a sample from well 20. There are no MCLs for thorium or uranium activity
54. In this investigation, a previously unidentified contaminant was discovered in Parkway well water samples in varying estimated concentrations, the highest levels being found in well 26. The unknown material was identified in November 1996 as isomers of THNA and THNP, collectively known as styrene-acrylonitrile (SAN) trimer. The SAN trimer is now known to be an unintended by-product resulting from the synthesis of styrene-acrylonitrile co-polymer. The presence of SAN trimer is attributable to the Reich Farm waste site groundwater contamination plume. The time of initial contamination is not known, nor are historic concentrations known. There is evidence of SAN trimer in the distribution system in March 1996 at levels of approximately 1 ug/l.
55. Exposure to SAN trimer was interrupted in November 1996 by temporary voluntary closure of the Parkway well field. By May 1997, activated carbon treatment of wells 26 and 28 was installed and treated water was discharged to the ground. (However, treated output from these wells may be pumped into the distribution system in times of high water demand.) Because of sporadic detection of SAN trimer in well 29, activated carbon treatment was installed for this well and for well 22 in June 1999, interrupting the potential exposure pathway.
56. The public health implications of SAN trimer contamination cannot yet be assessed. The toxicity testing of the SAN trimer, coordinated by the USEPA, will assist in making this determination.
57. Low levels of trichloroethylene were found in certain wells of the Parkway well field as early as 1986. The installation of a packed tower aeration treatment system at two wells (26 and 28) in 1988 served to reduce exposure to TCE, although TCE detections continued to occur due to sporadic contamination of an untreated well (#29). Subsequent activated carbon treatment of well 29 should interrupt exposure to TCE through this well.
58. While epidemiologic studies suggest an increased risk of leukemias and/or lymphomas from exposure to TCE-contaniinated drinking water, they are not considered conclusive.
59. Occupational radium exposure has been associated with increased risk of bone and paranasal sinus cancers in highly exposed workers. Radium in drinking water has been associated with increased bone cancer incidence in adolescents and with leukemia incidence in adults but not children, but the epidemiologic evidence is inconclusive.
60. Since 1989, federal and State agencies have recommended that all schools establish routine flushing programs to reduce exposure to these metals in drinking water. Exposure to accumulated lead can have adverse effects on the neurologic development of children. High levels of copper in drinking water may result in acute gastrointestinal effects.
61. Although the UWTR system appears typical in most respects, the presence of an unusual chemical at the Parkway well field, a sign of impact from the Reich Farm groundwater contamination plume, appears to be a characteristic unique to the area. Although little is known of the toxicologic implications of this impact, it is reasonable to consider exposure to this water source in epidemiologic investigations of childhood cancer in Dover Township
62. Treatment of the Parkway wells impacted by the Reich Farm groundwater contamination should be continued until such time that the plume no longer threatens the wells. The treatment should include methods to remove volatile and semi-volatile organic chemicals, such as packed tower aeration and/or granular activated carbon. Monitoring (at appropriate intervals) of the effectiveness of treatment systems is necessary to ensure that Reich Farm-related contaminants are not introduced into the distribution system of the community water supply.
63. When reduction of exposure to naturally occurring radiological activity in drinking water is necessary to meet applicable standards, use of wells with higher gross alpha activity should be minimized when possible.
64. To reduce exposure to lead from plumbing, particularly in those schools where lead and copper levels in first draw samples were elevated, the NJDHSS and NJDEP recommend that schools adopt a flushing program. This entails running the drinking water fountains each morning for a minute or two. In addition, schools may choose to provide a supplemental source of bottled water.
65. NJDEP and USEPA should continue to monitor the extent and movement of known contamination plumes in Dover Township, including those associated with the Reich Farm and Ciba-Geigy Superfund sites. Remedial efforts to contain and remove pollutants should be maintained to ensure the quality of future water supplies.
66. NJDEP should continue its evaluation of the potential existence of additional, non-target chemicals in the Reich Farm plume.
67. NJDEP and the U.S. Geological Survey should continue to conduct research into the occurrence and dynamics of radiological contaminants in the Kirkwood-Cohansey aquifer of southern New Jersey.
68. NJDHSS should continue to consider access to water from specific points of entry in the UWTR system in its "Case-control Study of Childhood Cancer in Dover Township (Ocean County), New Jersey, " using computer-modeled, historical re-constructions of the UWTR system under development by ATSDR.
69. USEPA should continue efforts to characterize the toxicology of SAN trimer, including attention to possible carcinogenicity following pre-natal or early post-natal exposure.
70. Where hazardous waste sites threaten water supplies, NJDEP and USEPA should consider expanded testing to encompass pollutant classes of local importance.