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Water Health Assessment
(Dover Township) Toms River, New Jersey
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Inorganic Chemicals
Draft for Public Comment -- November 16, 1999
Inorganic Chemicals
In general, levels of inorganic chemicals in the UWTR system and in the comparison samples are typical of groundwater-based community water systems (Tables 8a, 8b and gc). 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.
One well water sample contained 80 ug/l of lead (Berkeley well 33) in April 1996.
However, the Berkeley point of entry sample corresponding to this well had no detectable levels of lead, and nearby distribution samples did not contain elevated levels of lead. Two follow-up samples collected at this well showed lead levels at about 10 ug/l. Copper levels in all the point of entry and well water samples were well below the action level.
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.
Nickel was detected at low levels (< 10 ug/l) in several water samples from the distribution system, points of entry and wells. Its presence may be attributable to low levels in the source waters as well as to corrosion of pipes and plumbing. There is no current MCL for nickel, although a previous federal standard was 100 ug/l.
The detection of lead and copper in the distribution system (school) samples is largely due to corrosion-related rather than source-related influences. Groundwater in Ocean County (and in southern New Jersey in general) is naturally corrosive; that is, it is slightly acidic with low mineral content and, if untreated,
tends to dissolve metals from pipes and plumbing with which it is in contact. Although UWTR adds lime to adjust the pH and reduce corrosiveness of the water, corrosion of distribution system plumbing and individual building plumbing can still result in the leaching of metals into drinking water.
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. Typical barium levels in New Jersey community water supplies using groundwater range from < 1 to 3,000 ug/l (median 13 ug/l); those using surface water
range from < 1 to 1,320 ug/l (median 9 ug/l). The MCL for barium is 2,000 ug/l.
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.
According to the data from the NJDEP Bureau of Safe Drinking Water, the median mercury level in New Jersey community water systems is less than 0.5 ug/l for groundwater supplies and 0.5 ug/l for surface water supplies. The MCL for mercury is based on prevention of kidney toxicity.
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.
No chromium, cadmium, arsenic, antimony, beryllium, selenium, thallium or tin were found (at detection limits of I or 2 ug/l) in any of the UWTR distribution system (school) samples (Table 8a). These metals were either not detected or found near the detection limits of 1 or 2 ug/l in point of entry or well samples, in all cases well
below MCLS. 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 100ug/l (Table 8c).
Asbestos was not detected in any of the distribution (school) or comparison (school) water samples, nor in the new wells (43, 44 and 45) that came on line during the period of testing. Asbestos could occur in drinking water through the action of acidic water on asbestos-cement distribution system pipes. The NJDHSS Laboratory's detection
limit was 0.02 or 0.03 million fibers per liter; the MCL for asbestos fibers is 7 million fibers (over 10 microns in length) per liter.
Nitrate and nitrite were tested in most of the UWTR wells and points of entry. Total nitrate plus nitrite levels ranged from 0.06 to 2.4 milligrams per liter (mg/1). The MCL for nitrate plus nitrite is 10 mg/l.
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