INVESTIGATION OF HYDRO-GEOCHEMICAL PROPERTIES OF THE UPPER GLACIAL AQUIFER, JAMAICA, NEW YORK

The Upper Glacial Aquifer of Long Island New York consists of a layer of stratified sediment, which underlies Kings, Queens and Nassau Counties. Previous pumping of water from this aquifer resulted in the encroachment of salt water and other contaminants into the aquifer. With the significant reduction of water being removed from the aquifer, the water levels have recovered and now present potential flood hazards. This investigation attempts to determine the amount of recovery that has taken place, and if equilibrium has been achieved within the aquifer.

The study utilizes data gathered in situ through two USGS wells (40^o42’12.01” N, 73^o47’36.80” W; 40^o42’ 08.44”N, 73^o47’33.69"W) and real time data from one USGS monitoring well (40^o42’05.63”N, 73^o47’40.09”W; http://waterdata.usgs.gov/ny/nwis/uv/?site_no=404205073474101&PARAmeter_cd=72019,72020). located in the vicinity of York College, in Jamaica NY & 40^o42’05.63”N, 73^o47’40.09”W), to determine the fluctuations in water level as well as the gradient of the water flow. Preliminary data suggest that the gradient is consistent with existing regional groundwater flow. Several auger samples up to 180 cm were collected to determine the elemental abundance in surface soils and unsaturated aquifers materials. The 15 cm sections categorized into bulk (<2 mm) and fine (<0.25 mm) from each core were analyzed for a suite of elements by using handheld XRF (x-ray fluorescence spectrometry). NIST 2702 was run with each batch of 10 sections and was ± 3% within the reported value.

Fine fractions consistently show higher elemental abundance. Toxic metals As, Se, Mo, Ag, Cd, Sn, Sb, Hg were not detected in any section. Slightly elevated Pb in surface soils of all cores suggests the ambient Pb accumulation. The study also includes grain size analysis of cores and chemical parameters of groundwater from three wells to determine the aquifer hydro-chemical characteristics. Both field and laboratory analyses will be conducted for further generation of geochemical data from upper glacial aquifers.

Funded by US Dept. of Education (USDOE) Grant titled "Enhancing African American Students' Talents."