ELEVATED BORON ASSOCIATED WITH LITHIUM, SODIUM, SULFATE, AND ARSENIC IN NEWARK BASIN PRIVATE WELLS

Two hydrogeochemical environments have been identified within the Newark Basin of New Jersey with boron in private well water at concentrations above the U.S. Environmental Protection Agency health advisory for children (2,000 µg/L). In wells drilled in the lower Passaic Formation, elevated boron (up to 18,000 µg/L) is associated with high concentrations of lithium, sodium, sulfate, arsenic, hardness, total dissolved solids, and high pH. Elevated boron (up to 6,000 µg/L) in wells along the periphery of diabase intrusions is associated with normal concentrations of lithium and sulfate, moderately elevated sodium, elevated arsenic, very high pH, near zero hardness, and low total dissolved solids. The source of boron in these groundwaters has yet to be determined.

A private well study of 376 homes in the Passaic and Lockatong Formations, for arsenic and boron, found 94 homes (25%) exceeding the New Jersey arsenic maximum contaminant level, 18 homes (5%) exceeding the boron health advisory, and 12 homes (3%) exceeding for both arsenic and boron. The primary health concerns for boron exposure are testicular toxicity and infertility in males, as well as developmental effects for unborn babies, infants, and children. Removing boron from well water is extremely difficult due to its presence as an uncharged ion B(OH)₃ below pH 9.24. Experiments with reverse osmosis had only a 15% removal rate for boron even in well water at pH 9.9 where the B(OH)₄^- anion should predominate.