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Water Health Assessment
(Dover Township) Toms River, New Jersey
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Methods
Draft for Public Comment -- November 16, 1999
Methods
In order to perform a thorough evaluation of water quality, water samples from were analyzed for a much broader range of chemical and radiologic contaminants than is required under State and federal regulations. Samples were tested using several standard analytical methods. Some standard methods were modified or enhanced during the investigation to improve measurement of specific contaminants. In addition, non-standard methods were employed to analyze for unregulated classes of contaminants of potential concern.
For each method, all target analytes were evaluated. In addition, some methods were used to consider non-target analytes, that is, substances for which the method is not specifically tuned to measure but is capable of detecting its presence in the sample. For most of the tested contaminants, there are no established regulatory standards, nor are there past data from UWTR or data from other water systems to serve as appropriate comparisons.
The drinking water analyses described below were conducted primarily by the Division of Public Health and Environmental Laboratories of the NJDHSS (hereafter referred to as the NJDHSS Laboratory). Additional testing was done by the laboratory formerly maintained by the NJDEP, the Center for Advanced Food Technology (CAFT) at Rutgers University, QC Laboratories (a commercial laboratory in Southampton, Pennsylvania), and Lancaster Laboratories (a commercial laboratory in Lancaster, Pennsylvania).
For this investigation, all samples of the UWTR system were taken by staff of the NJDHSS or NJDEP. Chain-of-custody of sample containers was documented for each sample from the laboratory to collection and back to (and within) the laboratory. Trip and/or field blanks were collected with each sample batch to be analyzed using organic chemical methods. Laboratory quality control and quality assurance procedures are described for each method in the data package volumes compiled by the NJDHSS Laboratory.
Sampling Strategies
Initially, in March and April 1996, the UWTR system was characterized through the collection of samples from a number of locations in the distribution system, each point of entry then in operation, and several of the wells feeding the points of entry. Other, seasonally used points of entry were sampled as they were brought on line. Eventually, water from each individual well in the UWTR system was sampled.
Subsequent sampling patterns were determined on the basis of findings from these initial rounds of tests and the availability of enhancements to standard analytical methods. As will be discussed below, selected points of entry and wells were subjected to additional monitoring for radiological activity and organic chemicals. Table 3 provides a complete summary of the sampling efforts described in this Health Consultation.
In response to community concerns about the quality of water at Toms River area schools, initial distribution system samples were taken on March 28, 1996 at 21 public and private schools geographically dispersed throughout Dover Township and surrounding communities served by UW'FR. At each school, several sample bottles were filled with tap water in preparation for a variety of chemical and radiological analyses. Two samples were taken for lead and copper: a first draw sample, representing water that has been in contact with plumbing overnight, and a flushed sample, representing water as it was delivered to the school from the distribution system.
At the time of this initial sampling, water in the system originated from five points-of-entry -- South Toms River, Indian Head, Route 70, Berkeley and Parkway -- which feed into the system at various locations. These points of entry were sampled on April 4, 1996 for chemical and radiological analyses. The remaining three points-of-entry were sampled initially as they came on line: April 24, 1996 (Holly) and July 8, 1996 (Brookside and Windsor).
Four community water system wells outside of Dover Township were sampled to provide a basis for comparison, as was a commercial brand of bottled water. Two elementary schools in the Toms River School District but outside of both Dover Township and the UWTR service area (Beachwood and Pine Beach) were also sampled and tested for comparison.
Distribution system samples provide the best indication of the quality of water used by a consumer in the UWTR service area. Untreated well water does not necessarily represent what consumers drink, because: 1) treatment affects water quality (by removal of some contaminants and introduction of some treatment by-products); 2) at some points of entry, water from different wells is blended prior to entry into the system, and, once in the system, water from different points of entry may be mixed; and 3) contaminants such as lead and copper may be introduced by corrosion of water pipes and building plumbing. However, monitoring of untreated water is important to understand the condition of the sources of the water supplying the system rather than as a direct measure of human exposure to contaminants.
Analytical Methods
The standard water testing methods described below have been developed to measure the presence and/or amount of chemical contaminants or radiological activity in a given sample. Each method is designed to detect and quantify the list of specific "target analytes" as shown in Table 4.
Oritanic Chemical Analyses Water samples were tested using the following analytical methods. Organic chemical testing methods generally consist of three distinct steps. First, the target analytes may be extracted from the water; next, analytes may be separated from each other; and finally, analytes are detected and identified. Methods are capable of measuring different chemicals because of differences in the procedures used for extraction, separation and detection. Results are typically expressed in micrograms of chemical per liter of water (itg/1), also known as parts per billion (ppb).
In addition to the list of target analytes, the presence of other, non-target substances may be suggested by some chemical methods. Some of these non-target substances may be tentatively identified by the laboratory analyst although the method was not specifically designed to detect and measure them.
Volatile Organic Chemicals (USEPA Method 524.2) This method identifies and measures approximately 60 volatile organic chemicals in drinking water, including common commercial solvents and dry cleaning fluids, components of fuel oil and gasoline, components of plastics, and many other chemical products and intermediates. These substances are evaporated from the water sample, trapped, separated by a gas chromatograph, and detected with a mass spectrometer. During the investigation, the NJDHSS Laboratory enhanced the standard USEPA method to be able to measure acrylonitrile by a technique called selected ion monitoring.
Semi-volatile Organic Compounds (USEPA Methods 525.2 and 625) The 525.2 method identifies and measures over 35 organic chemicals including phthalates (common components in plastics), some insecticides and herbicides, polychlorinated biphenyis (PCBs), and polycyclic aromatic hydrocarbons (or PAHS, components of crude oil, tar, pitch, or smoke). The 625 method identifies and measures approximately 60 organic chemicals including chlorinated benzenes, ethers, nitrosamines, chlorinated and nitrogen-containing phenols, phthalates and PAHS. Method 625 is intended for analyses of wastewater, and although it has more target analytes than Method 525.2, its method detection limits are less sensitive. In both methods, semi-volatile compounds are extracted, separated by gas chromatography, and detected with a mass spectrometer. (In the course of the investigation, the NJDHSS Laboratory (and Lancaster Laboratories) developed an enhanced version of the 525.2 method capable of measuring styrene-acrylonitrile trimer.)
Pesticides, Pesticide Metabolites, and Related Chemicals (USEPA Methods 504, 505,
507, 515.2 and 531.2) These methods measure approximately 90 commonly used pesticides and pesticide metabolites including herbicides and insecticides, and PCBS. Initial distribution system (school) samples and well samples were analyzed using Methods 505 and 507 only (these two methods cover approximately 60 pesticides and their metabolites). The points of entry were initially analyzed using all pesticide methods. These methods use a variety of special extraction and separation steps, followed by measurement with special detectors. The 505 method analyses were conducted by the NJDHSS Laboratory. The other method analyses were conducted initially by the NJDEP laboratory, but upon closure of the NJDEP's chemical laboratory in July 1996, these analyses were conducted by QC Laboratories.
Non-volatile, High Molecular Weight Organic Chemicals (HPLC-MS Method) This non-standard method identifies and measures nonvolatile, ionic organic chemicals not detectable by the conventional analytical methods described above. The method uses solvent or solid phase extraction, separation by high performance liquid chromatography and detection by a mass spectrometer. This analysis was conducted for NJDEP by the CAFT laboratory at Rutgers.
Inorganic Chemical Analyses A variety of methods were used to detect and measure metals, asbestos and other inorganic substances.
Metals Distribution system, point of entry and well water samples were analyzed for the following metals using graphite furnace atomic absorption spectrometry and inductively coupled plasma spectrometry by the NJDHSS Laboratory: antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, molybdenum, nickel, selenium, thallitun and tin. Mercury was measured using cold vapor atomic absorption spectrometry.
Asbestos
Each school water sample and selected wells were analyzed for asbestos content (number of fibers greater than 10 microns per liter of water) by the NJDHSS Laboratory. Samples were filtered to trap fibers, and the filters were then examined using transmission electron microscopy.
Other Inorganic Substances Nitrate, nitrite, and other inorganic substances were measured on selected samples using standard methods by the NJDHSS Laboratory.
Radiological Activity Analyses Water analyses also included screening methods for "gross" radiological activity, followed by analyses of activity attributable to specific radioactive elemental isotopes. Analytical results are expressed in picocuries of radiological activity per liter of water (pCi/1).
Gross Alpha and Beta Activity Distribution system and points-of-entry samples were screened for gross alpha and beta radiological activity by the NJDEP laboratory and (upon closure of the NJDEP laboratory) by the NJDHSS Laboratory. Samples are evaporated on a stainless steel planchet and alpha and beta particle emissions are counted in a low-background gas flow proportional counter. (In the course of the investigation, the standard method was amended so that sample analysis took place within 48 hours of sample collection.)
Radium For samples where gross alpha activity results were above 5 pCi/L (and some with less than that amount), analyses for two isotopes of radium, radium-226 and radium-228, were conducted. Alpha activity is counted following special extraction procedures designed to isolate each isotope.
Other Tests of Radiological Activity Selected samples were analyzed for additional radiological characteristics: uranium, thorium, radon, and gamma activity. Uranium is extracted from water and measured with alpha spectroscopy using passivated implanted planar silicon. Radon activity in water samples is determined with a standard liquid scintillation technique. Ganuna spectroscopy quantifies ganm-ia activity attributable to specific radioactive isotopes, and is capable of -identifying radionuclides generated by human activities.
Public Health Evaluation of Results: Adult and Child Health Issues
To evaluate the public health implications of the drinking water tests for children and adults, results of analyses were compared to MCLs established by the USEPA and the NJDEP under the federal and State Safe Drinking Water Acts. For substances for which there is no established MCL, other health-based guidance levels set to protect adult and child health, if available, were used for comparison. This Public Health Consultation includes expanded discussion of the public health implications for those substances exhibiting a pattern of occurrence exceeding MCLs or other health-based guidance, or for which little or no toxicological information exists.
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