A GEOCHEMICAL AND SEDIMENTOLOGICAL SURVEY OF THE NORTHERN GATEWAY NRA, NEW YORK

The Gateway National Recreational Area (NRA) is one of America’s first urban national parks. It is located in the states of New York and New Jersey. It covers many units such as Sandy Hook, Staten Island and Jamaica Bay Unit of NY. The Jamaica Bay Unit has a deep history in which it served as a major dumping ground from early to mid 1900s and it is the home of two of New York’s major landfills. This geochemical and sedimentological research concentrate on the northern sites of the Jamaica Bay Unit with emphasis on heavy metal Loading and contaminants in the soil. Field and laboratory investigations included thorough physical and chemical characterization of soil samples, collected near the Fountain Avenue Landfill. Soil profiling was made up to 90 cm depth and samples were collected at 30 cm intervals. All samples were collected in low-tidal conditions and were preserved at 4^oC for further laboratory analysis. Sedimentological results illustrate large variations in the clastic content of the sediments. However, there is a proportional trend between all depths of each sampling site, where the sediments are medium to fine grained with a limited silt and clay. A heavy mineral analysis procedure was conducted on the sieved samples to identify the mineralogical composition of the sediments. Geochemical analysis of the samples was conducted by using a hand-held XRF instrument. This procedure provided critical information concerning the abundance of light and heavy elements within various soil samples. The results of this procedure (hand-held XRF data) were correlated to the mineralogical data in order to precisely determine point-source and origin of the soil enriched with metals. XRF results of the soil samples shows large spatial variation (50 to 200%) in Cl, K, Ca, Fe, Mn, Ti, Mn, Fe and Rb with average concentration of 1.6%, 1.0%, 1.9%, 3.6%, 1194 mg/kg, 8532 mg/kg, 284 mg/kg and 314 mg/kg respectively. Other heavy metals such as Pb, Zn and Sr with average concentration of 100 mg/kg, 11 mg/kg and 112 mg/kg depict low variation, although Pb were detected >500 mg/kg in three soil samples. As, Cu, Hg were not detected in any sample. These results will help to identify the source of dissolved heavy metals in Jamaica bay water.

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