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Water Health Assessment
(Dover Township) Toms River, New Jersey
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Background and Statement of Issues
Draft for Public Comment -- November 16, 1999
Purpose
To address concerns about elevated incidence of childhood cancer in Dover Township (Ocean County), the New Jersey Department of Health and Se'nior Services (NJDHSS) and the federal Agency for Toxic Substances and Disease Registry (ATSDR), in cooperation with the Ocean County Health Department (OCHD)
and the Citizens' Action Committee on Childhood Cancer Cluster (CACCCC), developed and are implementing a Public Health Response Plan (NJDHSS and ATSDR, 1996). One part of the plan is a thorough analysis of the quality of the public drinking water supply serving most of the township, conducted by the NJDHSS and the New Jersey
Department of Environmental Protection (NJDEP). Beginning in March 1996, samples of water have been collected from the community drinking water supply and analyzed for hundreds of organic and inorganic chemicals and for radiologic activity. The purpose of this evaluation is to identify whether there are any unusual characteristics of the water system that would warrant further public health investigation or actions to reduce exposure.
This Health Consultation presents the results of this water supply evaluation for the period March 1996 through June 1999. To establish context, this Public Health Consultation also provides a description and history of the community water supply and a summary of the sampling and analytical methods employed.
United Water Toms River
Most of Dover Township, Ocean County is served by United Water Toms River (UWTR), an investor-owned water company, formerly called Toms River Water Company. Portions of the township located on the barrier island are served by other community water systems (note 1). (These systems were not evaluated and are not
discussed in this Public Health Consultation.) Some mainland areas of the township are not served by any community water system; homes in these areas obtain their drinking water from private wells. It should also be noted that within the area served by -UWTR, some homes may not be connected to UWTR, but instead use private wells for drinking water. Figure 1 shows the present, approximate service area of UWTR. (Note that LTWTR also serves the
borough of South Toms River and part of Berkeley Township.)
Note 1 A community water system (or public water system) consists of any drinking water delivery system with at least 15 service connections or 25 residents.
Water Sources The approximately 85,000 customers of UWTR receive their drinking water by interconnected distribution system supplying water from eight "points of entry.
Each point of entry (located on Figure 1) is fed water by one or more groundwater wells tapping into underground water-bearing sands, or aquifers. UWTR currently operates more than 20 wells that feed these points of entry; the specific wells and well fields used at any time are determined by UWTR, in response to daily and seasonal changes in water demand. A schematic diagram illustrating the relationship between wells, points of entry, and
the distribution system is provided as Figure 2.
Table I summarizes the characteristics of each well in service in the system, arranged by point of entry, and including years of operation, well depth, pump' capacity, and the aquifer tapped. Most wells withdraw groundwater from the shallow Kirkwood-Cohansey aquifer system; others tap the deeper Piney Point and Potomac/Raritan/Magothy aquifers.
Water from each point of entry is treated with hypochlorite for disinfection, and lime for pH adjustment and corrosion control before entering the distribution system. Wells at some points of entry are also treated to control iron. After 1988, water from wells #26 and
#28 at the Parkway well field underwent packed tower aeration treatment to remove volatile organic chemicals. Granular activated carbon treatment was instituted for tile output from these two wells in May 1997. As of June 1999, Parkway wells #22 and #29 also are being treated with granular activated carbon.
History of Compliance Monitoring (Before 1996) Under State and federal regulations (note 2), all community water systems in New Jersey are required to test regularly the drinking water that is piped to homes and businesses. Drinking water must be tested by laboratories certified by NJDEP to conduct specific tests. Community water systems are required to report the results of analyses to the NJDEP; these results are then compared to drinking
water standards (called Maximum Contaminant Levels, or MCLS) established by regulations based on both federal and State Safe Drinking Water Acts. Where and how frequently samples are taken, and which laboratory tests must be done, are also set by U.S. Environmental Protection Agency (USEPA) and NJDEP rules under the federal and State Safe Drinking Water Acts, respectively.
Sampling location is an important consideration in drinking water testing. Samples of untreated well water reflect the quality of water as it is drawn from the underground aquifer. For regulatory compliance, samples for most contaminants are usually taken at the point of entry to the distribution system. Samples at these locations characterize treated water entering the distribution system. Samples taken in the distribution system provide a description of actual water quality
experienced by consumers because: 1) the concentration of some contaminants may be affected by the composition of the distribution system pipes or building plumbing (such as lead); 2) the concentration of some contaminants may change with time spent in the distribution system (such as disinfection by-products or bacteria).
Note 2. New Jersey Administrative Code, Title 7, Chapter 10, New Jersey Safe Drinking Water Act Regulations; U.S. Code of Federal Regulations, Title 40, Chapter 1, Subchapter D, Part 14 1, National Primary Drinking Water Regulations.
A single sample from a community water system that exceeds a drinking water standard does not necessarily mean that the standard is violated. NJDEP usually conducts or requires additional sampling to confirm the presence of contamination and to determine its extent and sources. For some kinds of contaminants subject to seasonal variation (such as disinfection by-products), multiple samples over a period of time are typically required before a regulatory decision is made.
UWTR drinking water is subjected to routine tests for approximately 80 regulated chemical, radiological and microbiological contaminants. These tests, the standards used to evaluate them, the sampling frequency, and UWTR's compliance history before 1996 are summarized in Table 2. Details of interest are provided below.
Drinking water at various locations in the distribution system and leaving each UWTR point of entry has been tested for volatile organic chemicals. 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). NJDEP regulations setting a MCL of I ug/l for TCE became effective in 1988. In response, UWTR completed installation of a packed
tower aeration treatment system (air stripper) in 1988 to remove volatile organic chemicals from wells #26 and #28. Since then, treatment has been generally effective at removing TCE, but there have been occasional low level detections due to treatment failures and sporadic occurrences of TCF- in well #29. 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.
The distribution system is monitored quarterly for disinfection by-products (that is,
trihalomethanes). All sample results have been low and typical for a community water supply that uses groundwater and disinfects with chlorine.
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.
Lead and copper have been tested in samples taken from different locations in the distribution system in accordance with state and federal regulations. These metals are commonly found in drinking water samples due to corrosion of building plumbing. Although the lead and copper test results met standards, UWTR has installed corrosion control treatment to comply with regulations, because it serves a relatively large population.
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.
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.
Microbiological testing at UWTR consists of approximately 100 samples per month tested for the presence of total coliform bacteria. Samples are taken from different locations in the water distribution system throughout the month. The total coliform bacteria test is an indicator for the possible presence of other, disease-causing bacteria. The absence of total coliform bacteria indicates that the water delivered to consumers is free
of disease-causing bacteria. There have been no bacteriological violations in the UWTR system.
National Priorities List (NPL) Sites in Relation to the Community Water Supply There
are two NPL sites in Dover Township (Ocean County), Ciba-Geigy (CERCLIS #NJDOOI502517) and Reich Farm (CERCLIS #NJD980529713). The source of Reich Farm contamination was the dumping in 1971 of chemical wastes from a Union Carbide Corporation facility in Bound Brook, New Jersey by a waste hauling contractor. Both sites are thought to have impacted certain community water supply wells at some time period. 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.
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.). These issues are or will be more fully described in other documents developed under the Public Health Response Plan, in particular the Public Health Assessment for Reich Farm (NJDHSS and ATDSR, 1999) and the Public Health Assessment for Ciba-Geigy currently in
preparation by NJDHSS and ATSDR.
Community Concerns
The elevated incidence of childhood cancer in Dover Township (NJDHSS, 1997) has raised concerns in the community about possible links with environmental contamination, particularly in relation to the two Superfund sites. At a public meeting in March 1996, members of the community expressed specific concerns about the community drinking water supply. To address this concern the NJDHSS and ATSDR, in cooperation with the NJDEP, committed
to extensive sampling and testing of the community water supply, which is the subject of this Public Health Consultation.
Statement of Issues
This Public Health Consultation comprehensively examines and evaluates the chemical and radiological characteristics of the UWTR supply, based on extensive sampling and analysis conducted from March 1996 to June 1999. In addition, the NJDHSS and ATSDR consider whether there are aspects of the community water supply that are unusual or unique, indicating that water-related exposures should be examined in the epidemiologic investigation of childhood cancer incidence in Dover Township.
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