CHARACTERIZATION OF REDOX STATE OF BROOKLYN-QUEENS AQUIFER SYSTEM, NEW YORK CITY

The groundwater supply system in Jamaica, Queens, New York City, consists of 68 supply wells in 44 well stations and several water storage tanks. In Jamaica, Queens a company called West Side Cooperation served as the site for storage and distribution of PCE/TCE between 1969 to 1992 at the 4.5 acre site. Improper handling of the chemicals has led to severe contamination of soil and groundwater. In order to improve the tracking of plumes and other sites that may have the potential to cause contamination of soil and groundwater in the future, a map of open and closed spills in Kings and Queens County was constructed and 2 aliquots, acidified and non-acidified, groundwater samples from both Westside Corporation and York College (The City University of New York) were collected and analyzed by using High Resolution Inductively Coupled Plasma Mass Spectroscopy (HR-ICP-MS) at Lamont-Doherty Earth Observatory (LDEO), Columbia University. Non-acidified samples were analyzed using Ion-Exchange Chromatography (IC) at Barnard College, Columbia University. The ICP-MS analysis provided concentrations of elemental Silicon, Phosphorous, Sulfur, Calcium, Sodium, Magnesium, Potassium, Strontium, Iron, Manganese and Arsenic. IC analysis provided concentrations of Fluoride, Chloride, Sulfate, Bromide and Nitrate as NO₃. Quality Assurance and Quality Control were monitored by also running NIST Standard 1640A, NIST Standard 1643E, and LDEO internal standard 2009. Standard calibration r-squared values ranged from 0.99918 to 0.99995. The results from the ICP-MS analysis for the redox sensitive elements were lower than expected. This might be due to sampling method, and or sample preparation procedure, which includes the need to centrifuge due to the presence of suspended solids thus yielding the need for initiating different methods for sampling. A closer look also needs to be taken at the interactions these trace metals have on the surface of minerals. This experiment will be carried out by Synchrotron Particle Accelerator facility at Stanford University. The primary thrust of this research is to help better monitor, predict and ultimately curtail plumes of contaminants to improve the quality of the environment and protect public health.