Data from the Private Well Testing Act Program
The test results from the PWTA Program can be divided into two categories: primary contaminants, that are biological or chemical substances regulated based on potential health effects and secondary parameters, which are regulated for non health-based purposes (e.g., aesthetics, taste, corrosivity).
The PWTA Program uses the same federal and state primary standards that apply to New Jersey's public water systems to define which wells "pass" or "fail" under the PWTA Program with two exceptions. As discussed in Part 1, New Jersey adopted a more stringent, MCL for arsenic of 5 µg/l compared to the federal MCL of 10 µg/l. In addition, since no MCL exists for lead, the ground water standard was used. The ground water standard is 5 µg/l.
Bacteriological: Fecal Coliform or Escherichia coli (E. coli)
Fecal waste from humans and animals may contain disease-causing microorganisms.
Illness can remove or
occur if contaminated water inactivate the pathogens.
is consumed without adequate Therefore, it is important to
treatment to detect fecal
contamination in ground water, especially for systems that do not treat the water prior delivery. Fecal contamination is usually determined by testing water for the presence certain fecal-derived “indicator” bacteria, such as total coliform, fecal coliform
to of or
Escherichia coli (E. coli). These bacteria are present in untreated wastes from and warm-blooded animals. The presence of these bacteria “indicates” that the contaminated and thus may contain disease-causing microorganisms.
humans water is
Sources – septic tanks, cracked sewer lines, contaminated surface waters including lakes, streams, rivers and wetlands, storm water runoff and detention/infiltration basins, runoff from agricultural lands, feedlots, stockyards, land-applied sludge or manure, manure storage areas and landfills.
Counties that Sampled – All counties are required to test for total coliform bacteria. Because the presence of total coliform bacteria is suggestive, but not conclusive proof that fecal contamination is present, all total coliform-positive samples are required to be further tested for either fecal coliform or E. coli bacteria. (Note: Many labs conduct total coliform and fecal coliform /E. coli tests simultaneously to avoid the extra cost and time-delay involved in conducting follow-up testing of total coliform -positive samples. Also, some methods are designed to test for both total coliform and E. coli simultaneously).
MCL – If a sample tests positive for either fecal coliform or E. coli, the well fails the test. The presence of either fecal coliform or E. coli is considered sufficient evidence of fecal contamination.