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Trenton, NJ, United States

Kauffman G.J.,University of Delaware | Homsey A.R.,University of Delaware | Belden A.C.,University of Delaware | Sanchez J.R.,Delaware River Basin Commission
Environmental Monitoring and Assessment | Year: 2011

In 1940, the tidal Delaware River was "one of the most grossly polluted areas in the United States." During the 1950s, water quality was so poor along the river at Philadelphia that zero oxygen levels prevented migration of American shad leading to near extirpation of the species. Since then, water quality in the Delaware Basin has improved with implementation of the 1961 Delaware River Basin Compact and 1970s Federal Clean Water Act Amendments. At 15 gages along the Delaware River and major tributaries between 1980 and 2005, water quality for dissolved oxygen, phosphorus, nitrogen, and sediment improved at 39%, remained constant at 51%, and degraded at 10% of the stations. Since 1980, improved water-quality stations outnumbered degraded stations by a 4 to 1 margin. Water quality remains good in the nontidal river above Trenton and, while improved, remains fair to poor for phosphorus and nitrogen in the tidal estuary near Philadelphia and in the Lehigh and Schuylkill tributaries. Water quality is good in heavily forested watersheds (>50%) and poor in highly cultivated watersheds. Water quality recovery in the Delaware Basin is coincident with implementation of environmental laws enacted in the 1960s and 1970s and is congruent with return of striped bass, shad, blue crab, and bald eagle populations. © 2010 Springer Science+Business Media B.V. Source

Rodenburg L.A.,Rutgers University | Guo J.,Rutgers University | Du S.,Rutgers University | Cavallo G.J.,Delaware River Basin Commission
Environmental Science and Technology | Year: 2010

The non-Aroclor congener 3,3′-dichlorobiphenyl (PCB 11) has been recently detected in air, water, biota, sediment, and suspended sediment. Although it has been known since at least the 1970s that this congener is produced inadvertently during the production of diarylide yellow pigments, this work presents the first evidence that the use of these pigments in consumer goods results in the dispersion of PCB 11 throughout the environment at levels that are problematic in terms of achieving water quality standards for the sum of polychlorinated biphenyls (PCBs). In this work, PCB 11 is measured at ppb levels in consumer goods that are likely to be discarded in ways that allow them to enter wastewater treatment plants and combined sewer overflows, including newspapers, magazines, cardboard boxes used for food packaging, and plastic bags. Also, using data sets acquired for the purpose of calculating total maximum daily loads (TMDLs) for PCBs, PCB 11 loads to the New York/New Jersey Harbor and Delaware River are calculated. Despite the fact that there are no known manufacturers of diarylide yellow pigments in the Delaware River watershed, the loads of PCB 11 to the Delaware River exceed the TMDL for the sum of PCBs by nearly a factor of 2. The ratio of PCB 11 to a characteristic dechlorination end product, PCB 4 (2,2′-dichlorobiphenyl), in these data sets indicates that dechlorination is not a significant source of PCB 11 in these systems. In the upper Hudson River, where extensive dechlorination of heavy PCB congeners occurs, the ratio is just 0.012. In contrast, downstream in the NY/NJ Harbor as well as in the Delaware River the ratio is much higher and more variable. Pigment use therefore appears to be the main source of PCB 11 in these systems, and this congener is likely to present a significant obstacle to achieving PCB water quality standards throughout the United States. © 2009 American Chemical Society. Source

Rodenburg L.A.,Rutgers University | Du S.,Rutgers University | Fennell D.E.,Rutgers University | Cavallo G.J.,Delaware River Basin Commission
Environmental Science and Technology | Year: 2010

One of the few pathways for environmental transformation of polychlorinated biphenyls (PCBs) is microbial dechlorination under anaerobic conditions, which is reported to occur in contaminated sediments of rivers, lakes and harbors. The goal of this work was to determine whether PCB dechlorination occurs in built waste treatment environments. We analyzed a large database on PCB congener concentrations in effluents and some influents of facilities in the Delaware River Basin. Positive matrix factorization was used to identify the sources of PCBs and to look for evidence of dechlorination. Seven factors were resolved from the data set of 89 congeners in 645 samples. Two of the resolved factors represented dechlorination signals. One of these was dominated by PCBs 4 and 19 and represents an advanced stage of dechlorination of Aroclors to di- and trichlorinated congeners. This dechlorination signal was most prevalent in effluents from sites with contaminated groundwater and from wastewater treatment plants (WWTPs) that serve combined sewers or treat landfill leachate. The other dechlorination signal appeared to represent an intermediate stage of dechlorination, because it was dominated by two coeluting groups of tetrachlorinated congeners: PCBs 44 + 47 + 65 and 45 + 51. This partial dechlorination signal was most prevalent in the 40 WWTPs with separate (sanitary) sewer systems, where it often comprised more than 20% of the PCBs in the effluents. Both dechlorination signals were present in WWTP influents, but were not observed in stormwater runoff, suggesting that dechlorination occurs in sewers. This work represents the first convincing evidence of PCB dechlorination occurring outside of contaminated aquatic sediments or anaerobic digesters. The results suggest that PCBs are dechlorinated by anaerobic bacteria in sewers, landfills, and contaminated groundwater. These two dechlorination signals comprise about 19% of the total loads of PCBs to the Delaware River from the sampled dischargers. © 2010 American Chemical Society. Source

Praipipat P.,Rutgers University | Rodenburg L.A.,Rutgers University | Cavallo G.J.,Delaware River Basin Commission
Environmental Science and Technology | Year: 2013

Polychlorinated biphenyls (PCBs) are toxic, persistent, bioaccumulative compounds that threaten water quality in many areas, including the Delaware River. In 2003, total maximum daily loads for PCBs were promulgated for the tidal portion of the river, requiring the collection of a massive and unprecedented data set on PCBs in an urban estuary using state of the art, high-resolution high mass spectrometry (EPA method 1668 revision A). In previous publications, this data set has been examined using positive matrix factorization (PMF) to apportion PCB sources in the air, water, and permitted discharges to the river. Here, the same technique is used to apportion PCB sources in the sediment. This holistic approach allows the comparison of source types and magnitudes to the air, water, and sediment, and allows conclusions to be drawn about the cycling of PCBs in a typical urbanized estuary. A data set containing 87 chromatographic peaks representing 132 PCB congeners in 81 samples and 6 duplicated samples was analyzed. Seven factors were resolved. Three represent relatively unweathered Aroclors. Two were related to the non-Aroclor sources of diarylide yellow pigments and titanium tetrachloride production. The two remaining factors were probably originally related to Aroclors, but they are so highly weathered as to be unrecognizable as Aroclors, and thus have probably resided in the river for a long time. Comparing the abundance of the resolved PCB factors in the air, water, discharges, and sediment demonstrates that high molecular weight formulations, such as Aroclor 1260 and PCBs 206, 208, and 209 produced during titanium tetrachloride synthesis accumulate preferentially in the sediment, in keeping with their greater hydrophobicity. In contrast, lower molecular weight formulations, including the products of PCB dechlorination occurring in sewers, do not accumulate appreciably. PCB 11 from pigment use does accumulate in sediments and also seems to be distributed throughout the estuary via the atmosphere. © 2013 American Chemical Society. Source

Ostfeld A.,Technion - Israel Institute of Technology | Barchiesi S.,A+ Network | Bonte M.,KWR Watercycle Research Institute | Collier C.R.,Delaware River Basin Commission | And 6 more authors.
Journal of Water and Climate Change | Year: 2012

Despite uncertainty pertaining to methods, assumptions and input data of climate change models, most models point towards a trend of an increasing frequency of flooding and drought events. How these changes reflect water management decisions and what can be done to minimize climate change impacts remains unclear. This paper summarizes and extends the workshop outcomes on 'Climate Change Impacts on Watershed Management: Challenges and Emerging Solutions' held at the IWA World Water Congress and Exhibition, Montréal, 2010, hosted by the IWA Watershed and River Basin Management Specialist Group. The paper discusses climate change impacts on water management of freshwater ecosystems and river basins, and illustrates these with three case studies. It is demonstrated through the case studies that engagement of relevant stakeholders is needed early in the process of building environmental flows and climate change decision-making tools, to result in greater buy-in to decisions made, create new partnerships, and help build stronger water management institutions. New alliances are then created between water managers, policy makers, community members, and scientists. This has been highlighted by the demonstration of the Pangani integrated environmental flow assessment, through the Okavango River Basin case study, and in the more participatory governance approach proposed for the Delaware River Basin. © IWA Publishing 2012. Source

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