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March 2, 2004

Contact: Fred Mumford
(609) 984-1795

DEP Releases Initial Results of Private Well Testing Program
Home Buyers Learn of Water Quality during Property Transactions

(04/15) Trenton - Department of Environmental Protection (DEP) Commissioner Bradley M. Campbell today announced test results from more than 5,000 private drinking water wells sampled across New Jersey from September 2002 through March 2003. The results show an eight percent failure rate for meeting health-based standards for drinking water contaminants, excluding lead.

"The results demonstrate the importance of testing residents' drinking water sources for a variety of contaminants that may need treatment to ensure a safe supply," said Commissioner Campbell. "When contamination issues arise, county and local health officials step in to assist residents taking corrective action."

The report provides a summary of 5,179 well tests triggered by real estate transactions. Based on the results of the first six months of the program, 92 percent of the 5,179 wells, which represent approximately one percent of New Jersey homes with private wells, passed all the required health-based standards, with the exception of lead. For reasons presented below, the lead results are not included in any of the summary results.

Of the eight percent (417 wells) that exceeded a health-based drinking water standard, the most common reason for failure statewide was elevated nitrate levels (189 wells) followed by fecal coliform (92 wells) and volatile organic compounds (71 wells). In the counties where arsenic and mercury testing was required, 72 wells failed for arsenic and 14 wells failed for mercury. Elevated levels of nitrates usually come from fertilizer runoff or septic leaching, fecal coliform stems from septic leaching, sewer leaks or animal waste runoff, while volatile organic compounds originate from improper use and disposal of solvents and fuels. Arsenic occurs naturally in soil and ground water in the Piedmont region of the state and mercury is linked to leaching in soils of air deposition and past pesticide use.

Treatment systems for these various contaminants range from $200-$4,000 with additional costs for annual maintenance. State money from DEP's Spill Fund pays for residents' treatment and maintenance costs for volatile organic compounds and mercury contamination found.

"Families have the right to know whether their drinking water is safe when purchasing homes with private wells," said Commissioner Bradley M. Campbell. "This program is successful due to support from local and county health officers across the state who provide information to persons involved with the private well testing process."

New Jersey is the only state that requires mandatory statewide private well testing upon sale of a home. DEP provides local and county health officials the results of well tests that show an exceedance of a primary or secondary drinking water standard within five days of receipt of the data from laboratories performing the analyses. Only primary drinking water standards are based on health concerns. Secondary drinking water standards address aesthetics such as corrosivity, taste, odor and color. The fundamental goal of the Private Well Testing Act is to ensure that purchasers and lessors of properties served by private wells are fully aware of the quality of the untreated drinking water sources prior to sale or lease. In the future, as more sample results are received, DEP will perform updates to the report's summary tables (Appendix B) by county and municipality of the quality of the water sources that supply New Jersey's private wells.

The private well tests were conducted on untreated (raw) water samples collected prior to entering any water treatment system. Many houses or wells may already have treatment systems in place to remove or lessen the degree of contamination. Although not required, DEP recommends post-treatment samples collected at a kitchen tap to evaluate the effectiveness of a treatment system. The Private Well Testing Act requires landlords of property with private wells (non-public water systems) to complete testing of their water source and to provide notice to their tenants by March 14, 2004. The requirement includes a test once every five years from the initial sampling date.

Shortly after the private well testing program began in September 2002, county and local health officials and DEP staff noted that some of the reported lead results were unexpectedly high. Local health departments often could not confirm the lead results through careful confirmatory sampling. Previously, the presence of lead had been detected only rarely in well water. In most cases high lead levels were attributed to well structures or plumbing, not ground water sources. As a result DEP considers the lead results suspect and did not include them in summary data.

The suspect lead results indicate 640 wells (12 percent) out of the 5,179 tested had levels above the state's Ground Water Quality Standard of 10 parts per billion. Public water systems must act to reduce the corrosiveness of the water when 10 percent of homes within their distribution system tested fall above 15 parts per billion. Lead levels reported in the private wells tested ranged from 1 to12,000 parts per billion, which does not correlate to past ground water studies in New Jersey and indicates a likely problem with the sampling location. A research study is underway with Rutgers University to further evaluate lead sampling and analytical techniques so that DEP may better understand the lead sampling results. A water sample taken at the kitchen tap is being used to help determine actual lead levels being consumed in homes after an elevated level is found during a test from plumbing closer to the well.

The private well tests also look for three naturally occurring secondary parameters: pH, iron, and manganese. A total of 3,089 wells tested (59 percent) exceeded one or more of the recommended limits for secondary parameters. Of the 5,179 wells tested, 2,047 had pH values outside the recommended range of 6.5 to 8.5. Both iron and manganese are inorganic ions that occur naturally in soils and rocks throughout the state. Of the 5,179 wells, 1,457 reported iron levels above the recommended standard of 0.3 mg/l. For manganese, 1,027 of the wells were above 0.05 mg/l, the recommended standard. Testing for secondary parameters determines if the water is suitable for laundering, plumbing, and showering or if prior treatment is needed.

All private well test water samples are analyzed for a core set of parameters: total coliform (if positive, fecal coliform/E. coli), nitrate, all 26 volatile organic compounds with established drinking water standards called maximum contaminant levels, lead, iron, manganese and pH. In some counties, samples must also be tested for the presence of arsenic or mercury and radiological contamination. Laboratory results are submitted to the DEP electronically.

If a well demonstrates an exceedance, or failure, the local health agency normally notifies the well owner plus neighboring homes and businesses of potential problems with the water supplies. For more information about the Private Well Testing Act Program, including treatment methods available for private wells and health effects associated with contaminants, visit



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