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Research about Maryland, New Jersey

Source-linked reports with geographic coverage including Maryland, New Jersey.

4 recordsLinked to original sources

Evidence for shelf acidification during the onset of the Paleocene-Eocene Thermal Maximum

A transect of paleoshelf cores from Maryland and New Jersey contains a ~0.19 m to 1.61 m thick interval with reduced percentages of carbonate during the onset of the Paleocene-Eocene Thermal Maximum (PETM). Outer paleoshelf cores are barren of nannofossils and correspond to two minor disconformities. Middle paleoshelf cores contain a mixture of samples devoid of nannofossils and those with rare specimens characterized by significant dissolution (i.e., etching). The magnitude of the decrease in carbonate cannot be explained by dilution by clastic material or dissolution resulting from the oxidation of organic matter during early diagenesis. The observed preservation pattern implies a shoaling of the calcite compensation depth (CCD) and lysocline to the middle shelf. This reduced carbonate interval is observed during the onset of the PETM on other continental margins raising the possibility that extreme shoaling of the CCD and lysocline was a global signal which is more significant than in previous estimates for the PETM. An alternative scenario is that shoaling was restricted to the northwest Atlantic, enhanced by regional and local factors (eutrophication from rivers, microbial activity associated with warming) that exacerbated the impact of acidification on the shelf.

Maryland, New Jersey

Demonstration and validation of a regenerated cellulose dialysis membrane diffusion sampler for monitoring groundwater quality and remediation progress at DoD sites: Perchlorate and ordnance compounds

This final technical report documents the demonstration and validation of regenerated cellulose dialysis membrane diffusion samplers (RCDM samplers) for use in collecting groundwater samples for perchlorate and a suite of explosives compounds. This project, ER-0313, was funded by the Environmental Security Technology Certification Program (ESTCP). The primary objectives of the project were; (1) to determine the usefulness of RCDM samplers in collecting perchlorate and a suite of explosives compounds from groundwater, (2) to determine the optimum equilibration times for these constituents to diffuse into the RCDM sampler, (3) to compare water-quality results and sampling costs from samples collected with RCDM samplers to samples collected with a low-flow purging technique, and (4) to transfer the technology while gaining regulatory acceptance. Equilibration times were determined in bench-scale testing for perchlorate and 14 nitroaromatic and nitramine explosives compounds. Field comparisons were conducted at two Department of Defense (DoD) sites: (1) Aberdeen Proving Grounds (APG), Maryland, and, (2) Picatinny Arsenal, New Jersey. Samples collected with the two sampling techniques were compared graphically and statistically to determine the significance of any differences found. RCDM samplers were found to cost significantly less than samples collected with a low-flow purging procedure. Sampling time was reduced by 84%, compared to low-flow purging. The total sampling costs per sample were calculated to be 71% less with an RCDM sampler, compared to low-flow purging.

Maryland, New Jersey

Radon-222 and its parent radionuclides in groundwater from two study areas in New Jersey and Maryland, U.S.A.

A study of groundwater chemistry and radionuclide mobility in New Jersey and Maryland was conducted to investigate natural processes that control the mobility of radionuclides in the water-rock system. Groundwater was sampled from two geological units in New Jersey and from six in Maryland. The water sampled was from aquifiers in fractured metamorphic rocks of varying composition and metamorphic grade. In both areas, groundwater chemistry was affected most by aquifier mineralogy and lithology; concentrations of total dissolved U, 226Ra and 222Rn were similarly affected. In evey sample for which measurements were made, dissolved Utotal and 226Ra were present in much lower concentrations than 222Rn when expressed in terms of their radioactivity. On the other hand, the total amount of 222Rn that could be produced in these rocks, given their U contents, is much higher than the concentrations observed in groundwater. Thus, the emanating efficiencies of the aquifer rocks studied must be near 10% or less. Such low emanating efficiencies require that a fraction of the 226Ra in the rock be located close to the water-rock interface so that 222Rn, when produced, can be rapidly and efficiently transferred to the aqueous phase. This condition is established when a similar fraction of the U is in a readily leachable position. No known U or Ra solids were supersaturated in any of the samples. Thus, adsorption processes probably play a role in limiting mobilities of Utotal and 226Ra. Concentrations of Utotal and 226Ra found in the water samples are comparable to those found in experimental studies of adsorption onto mineral surfaces. ?? 1991.

Maryland, New Jersey

Effects of environmental contaminants on snapping turtles of a tidal wetland

Snapping turtles (Chelydra serpentina) were collected from a brackish-water and a nearly freshwater area in the contaminated Hackensack Meadowlands of New Jersey and an uncontaminated freshwater area in Maryland to determine the effects of environmental contaminants on a resident wetland species. No turtles were observed or caught in the Meadowlands at two trapping sites that were the most heavily contaminated by metals. Snapping turtles from the brackish-water area had an unusually low lipid content of body fat and reduced growth compared to turtles from the fresh-water areas in New Jersey and Maryland. Despite the serious metal contamination of the Hackensack Meadowlands, the metal content of kidneys and livers from New Jersey turtles was low and not greatly different from that of the Maryland turtles. Organochlorine pesticide concentrations in body fat were generally low at all three study areas. Polychlorinated biphenyls (PCBs) concentrations in fat were highest in male turtles from the New Jersey brackish-water area. Analysis of blood for amino-levulinic acid dehydratase, albumin, glucose, hemoglobin, osmolality, packed cell volume, total protein, triglycerides, and uric acid failed to reveal any differences among groups that would indicate physiological impairment related to contaminants.

Maryland, New Jersey