PREDICTING METAL CONTAMINATION IN THE NEWARK BASIN USING A COMPOSITE STRATIGRAPHIC RECORD

Many of the black shales found in the Newark Basin contain high concentrations of metals including arsenic and uranium, and fractures within these units serve to localize groundwater movement (e.g., Serfes et al., 2010; Serfes et al., 2005; Szabo et al., 1997). Many people who live in the Newark Basin rely on well water and are at risk of exposure from certain metals such as arsenic and uranium if their water is sourced from metal-rich intervals and is not properly filtered.

In this project, our principal goal is to test whether the inventory of metals recovered from the comprehensive geochemical database produced from the composite stratigraphic record of the Newark Basin is useful in predicting concentrations of those metals in time-equivalent units from the same formation at different positions in the basin at distances on the order of 10s of km. We will do this in three parts: 1) Using X-Ray Fluorescence (XRF), we will produce quantitative estimates of metal concentrations from several small core samples from an area near Trenton, NJ with a particular focus on arsenic and uranium; 2) Refine our estimates of the concentration of these metals from the time equivalent section of the composite record and test whether this comprehensive chemical stratigraphy has predictive power that extends to larger distances across the basin; 3) Test water from open monitoring wells from this region to see if the prediction from the concentration of metals in bedrock is consistent with what we observe in the local groundwater system. This project gives us the opportunity to test how useful an estimate of the metal content in one section of bedrock is to the prediction of metal concentration in correlative sections at a greater distance.

Serfes, M., Herman, G., Spayd, S., and Reinfelder, J., 2010, Sources, mobilization and transport of arsenic in groundwater in the Passaic and Lockatong Formations of the Newark basin, New Jersey: New Jersey Geological Society Bulletin, v. 77, p. 1-40.

Serfes, M. E., Spayd, S. E., and Herman, G. C., 2005, Arsenic Occurrence, Sources, Mobilization, and Transport in Groundwater in the Newark Basin of New Jersey, Advances in Arsenic Research, Volume 915, American Chemical Society, p. 175-190.

Szabo, Z., Taylor, T. A., Payne, D. F., and Ivahnenko, T., 1997, Relation of hydrogeologic characteristics to distribution of radioactivity in ground water, Newark Basin, New Jersey, 95-4136.