We synthesized existing data on chemical contaminants in Long Island Sound (LIS) from published reports and unpublished databases. We found several cases of systematic differences between data sources, which complicated the tasks of understanding the health of LIS and of identifying trends over time. Of the three media examined-water, sediment, and biota-sediment (especially in western LIS) most often exhibited pollutant concentrations that were high relative to guidelines and to other estuaries. These high sediment concentrations did not appear to be efficiently transmitted to biota. With the exception of Cd, median pollutant levels in embayment sediments were not higher than in open-water sediments, but the highest levels found in embayments were much higher than at open-water sites, especially for Ag and Hg. Trends over time in contaminant levels were mixed. We identify the most problematic contaminants in LIS and recommend adding Ag to the LIS Study's List of Contaminants of Concern.

No abstract

Increased anaerobic selector hydraulic retention times (HRTs) in a high-purity oxygen activated sludge process resulted in an increase in soluble orthophosphate release and biodegradable COD removal at aeration solids retention times (SRTs) ranging from 1.1 and 1.7 days. Under operating conditions that included biological foam recycling, a well established phosphorus accumulating organism community was observed at HRTs higher than 55 minutes that resulted in a decrease in filament counts and foam stability, providing effective operating conditions for foam control. While enhanced biological phosphorus removal was observed at HRTs between 20 and 60 minutes, its effectiveness with respect to foam control was compromised due to excessive foam trapping and recycling. Thus, increased anaerobic selector HRTs and low aeration SRTs can provide effective measures for biological foam control under conditions that minimize the impacts of foam trapping or that eliminate biological foam recycling.

Increased anaerobic selector hydraulic retention times (HRTs) in a high-purity oxygen activated sludge process resulted in an increase in soluble orthophosphate release and biodegradable chemical oxygen demand removal, confirming that enhanced biological phosphorus removal occurs at aeration solids retention times (SRTs) below 1.7 days. Under operating conditions that included biological foam trapping and recycling, an anaerobic selector with HRTs higher than 55 minutes resulted in a decrease in filament counts and effective foam control. Effective norcardioform control is achieved through the combination of metabolic selective pressure and increased soluble organic substrate removal in the anaerobic selector and low aeration SRT. Water Environ. Res., 79, 472 (2007).