CONSTRAINING THE SOURCE OF BORON THAT LOCALLY CONTAMINATES THE GROUNDWATER IN THE NEWARK BASIN, NEW JERSEY

The Newark basin was formed during the Triassic-Jurassic rifting and subsequently filled with up to 8 km of the Triassic-Jurassic lacustrine rocks. In this basin, the groundwater is locally contaminated with Boron, exceeding the limit (500 ug/L to 3,000 ug/L) set by the EPA health advisory. Hence, this current project aims at identifying the source of Boron and associated trace elements by analyzing selected ore deposits (Barite, Sphalerite, Galena, Pyrite, Chalcopyrite) and the Late Triassic lacustrine rocks of the Newark basin.

Preliminary results show that sphalerite, galena, barite, and the lacustrine rocks show a low concentration of boron (<40 ppm). Therefore, on the basis of the available data, these ore deposits and the host rocks are not possible sources of boron. The Ba-Pb-Zn-rich fluids flowing through these Boron-depleted lacustrine rocks are, therefore, depleted in Boron. Hence, the analyzed ore are also Boron-depleted and are not the source of Boron that contaminated groundwater. Sulfides (pyrite and chalcopyrite) associated with diabase can, however, be a source of boron.