DefinitionPercent of tested private wells with mercury levels exceeding the maximum contaminant level of 2 micrograms per liter (ug/l)
NumeratorNumber of tested private wells with mercury levels exceeding the maximum contaminant level of 2 ug/l in a specified period of time
DenominatorNumber of tested private wells in a specified period of time
Data Interpretation IssuesNine southern New Jersey counties (Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester, Monmouth, Ocean, and Salem) are required by the New Jersey Private Well Testing Act (PWTA) to monitor for mercury. All sampled wells are located within the Coastal Plain province. Less than one percent of the wells contained mercury levels above the drinking water maximum contaminant level (MCL) of 2 ug/l. The source of mercury in these private wells is not clear.
Why Is This Important?People may be exposed to mercury from a variety of sources, including drinking water. Mercury, carried by wind and rain, is found throughout the environment mostly due to the release of naturally occurring mercury from rock and soil; burning of coal and oil that contains small amounts of mercury; release of mercury from metal smelters; and incineration of materials that contain mercury, such as batteries. Too much mercury in the human body can cause serious damage to the brain, nervous system and kidneys. Young children and developing fetuses are at greatest risk for harmful effects of mercury.
How Are We Doing?Between September 2002 and April 2014, less than 1% of 43,441 private wells in New Jersey tested for mercury exceeded the MCL of 2 micrograms per liter. Mercury exceedances were most commonly found in Camden (2.6% of wells), Cumberland (1.8% of wells), Atlantic (1.7% of wells) and Gloucester (1.7% of wells) Counties. Online maps showing mercury exceedances are available at the county level, municipal level, and for 2 mile by 2 mile grids from NJDEP, [http://arcg.is/1CPkHyC]
What Is Being Done?The New Jersey Private Well Testing Act (N.J.S.A. 58:12A-26 et seq.) became effective in September 2002. The PWTA requires the buyer or the seller of a property to test untreated well water prior to the sale and review the results prior the closing of title. It also requires landlords to test the private well water supplied to their tenants every five years and provide their tenants with a written copy of the results. The data generated by this program are provided to the homeowners by the laboratory performing the analyses and then sent to the New Jersey Department of Environmental Protection (NJDEP). The NJDEP notifies local health agencies when a well within their jurisdiction is tested under the PWTA. The data from the PWTA are used by NJDEP to assess the quality of the water from private wells throughout the state.