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Whittier, California, United States

Maruya K.A.,Southern California Coastal Water Research Project Authority | Dodder N.G.,Southern California Coastal Water Research Project Authority | Sengupta A.,Southern California Coastal Water Research Project Authority | Smith D.J.,California Regional Water Quality Control Board | And 3 more authors.
Environmental Toxicology and Chemistry | Year: 2016

To examine the occurrence and fate of contaminants of emerging concern (CECs) and inform future monitoring of CECs in coastal urban waterways, water, sediment, and fish tissue samples were collected and analyzed for a broad suite of pharmaceuticals and personal care products (PPCPs), commercial and/or household chemicals, current use pesticides, and hormones in an effluent-dominated river and multiple embayments in southern California (USA). In the Santa Clara River, which receives treated wastewater from several facilities, aqueous phase CECs were detectable at stations nearest discharges from municipal wastewater treatment plants but were attenuated downstream. Sucralose and the chlorinated phosphate flame retardants tris(1-chloro-2-propyl) phosphate (TCPP), tris(1,3-dichloro-2-propyl) phosphate (TDCPP), and tris(2-chloroethyl) phosphate (TCEP) were most abundant in water, with maximum concentrations of 35 μg/L, 3.3 μg/L, 1.4 μg/L, and 0.81 μg/L, respectively. Triclocarban, an antimicrobial agent in use for decades, was more prevalent in water than triclosan or nonylphenol. Maximum concentrations of bifenthrin, permethrin, polybrominated diphenyl ethers (PBDEs), and degradates of fipronil exceeded CEC-specific monitoring trigger levels recently established for freshwater and estuarine sediments by factors of 10 to 1000, respectively. Maximum fish tissue concentrations of PBDEs varied widely (370 ng/g and 7.0 ng/g for the Santa Clara River and coastal embayments, respectively), with most species exhibiting concentrations at the lower end of this range. These results suggest that continued monitoring of pyrethroids, PBDEs, and degradates of fipronil in sediment is warranted in these systems. In contrast, aqueous pharmaceutical concentrations in the Santa Clara River were not close to exceeding current monitoring trigger levels, suggesting a lower priority for targeted monitoring in this medium. Environ Toxicol Chem 2016;35:1986–1994. © 2016 SETAC. © 2016 SETAC

McDannel M.,Los Angeles County Sanitation Districts
Proceedings of the Air and Waste Management Association's Annual Conference and Exhibition, AWMA | Year: 2014

A discussion on the generation and utilization of biogas generated from anaerobic digestion of (AD) organic solid waste and wastewater streams covers Zero Waste Energy's approach using dry fermentation, AD to the organic fraction of the solid waste stream through examples of their operating projects and selected projects under development; Harvest Power's anaerobic digestion technologies and projects; options to increase diversion of organic material from landfills, including evaluation of AD; and efforts of one agency to address tightening emission limits on reciprocating internal combustion engines by adapting natural gas emissions control technology to biogas engines. This is an abstract of a paper presented at the AWMA's 107th Annual Conference & Exhibition (Long Beach, CA 6/24-27/2014).

Booth J.A.T.,City of Los Angeles Environmental Monitoring Division | Woodson C.B.,University of Georgia | Sutula M.,Southern California Coastal Water Research Project Authority | Micheli F.,Stanford University | And 6 more authors.
Limnology and Oceanography | Year: 2014

Here we examine a 50+ yr data set from a regionally coordinated southern California water quality monitoring program to assess temporal trends and determine whether nearshore waters are exhibiting changes in dissolved oxygen (DO) content similar to those reported offshore. DO in sub-mixed layer nearshore waters (≤ 10 km from shore) have declined up to four times faster than reported for offshore waters over the last 15 yr. These trends were evident over depth, and along isopycnals. They have no precedent over the past 50 yr and do not appear to be attributable primarily to large-scale climate variability in ocean DO. Coastal biophysical processes, including increased phytoplankton biomass in surface waters, are likely contributing to the recent elevated rate of DO decline in nearshore waters, as evidenced by higher rates of increase in apparent oxygen utilization. It is unclear whether these processes result from upwelling-derived or anthropogenic nutrient inputs. © 2014, by the Association for the Sciences of Limnology and Oceanography, Inc.

Somasundaram S.,Advanced Earth science Inc. | Shenthan T.,Advanced Earth science Inc. | Benson C.,University of Wisconsin - Madison | Nannapaneni S.,Los Angeles County Sanitation Districts
Unsaturated Soils - Proceedings of the 5th International Conference on Unsaturated Soils | Year: 2011

Development of soil water characteristic curves (SWCC) and unsaturated hydraulic conductivity functions for materials containing a significant fraction of coarse granular material, including gravels, cobbles and small boulders, is constrained by the limitations of laboratory equipment and test specimen sizes. This paper presents an approach for obtaining the unsaturated hydraulic parameters for such materials by testing the matrix materials that primarily govern the hydraulic behavior, and developing and applying oversize correction functions to account for the influence of the larger particles and matrix density/porosity. Laboratory SWCC and saturated hydraulic conductivity (Ks) tests on minus #4, minus 25-mm and minus 75-mm fractions of desert alluvium, mine ore, and mine overburden materials were used to develop the oversize correction functions for Ks, and the van Genuchten/Mualem parameters α, n, θs and θr. © 2011 Taylor & Francis Group, London.

Sengupta A.,Southern California Coastal Water Research Project Authority | Lyons J.M.,California Regional Water Quality Control Board | Smith D.J.,California Regional Water Quality Control Board | Drewes J.E.,Colorado School of Mines | And 3 more authors.
Environmental Toxicology and Chemistry | Year: 2014

To inform future monitoring and assessment of chemicals of emerging concern (CECs) in coastal urban watersheds, the occurrence and fate of more than 60 pharmaceuticals and personal care products (PPCPs), commercial/household chemicals, current-use pesticides, and hormones were characterized in 2 effluent-dominated rivers in southern California (USA). Water samples were collected during 2 low-flow events at locations above and below the discharge points of water reclamation plants (WRPs) and analyzed using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. Approximately 50% of targeted CECs were detectable at stations downstream from WRPs, compared with <31% and <10% at the reference stations above the WRPs. Concentrations of chlorinated phosphate flame retardants were highest among the CECs tested, with mean total aggregate concentrations of tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCPP) of 3400ng/L and 2400ng/L for the 2 rivers. Maximum in-stream concentrations of pyrethroids (bifenthrin and permethrin), diclofenac, and galaxolide exceeded risk-based thresholds established for monitoring of CECs in effluent-dominated receiving waters. In contrast, maximum concentrations of PPCPs commonly detected in treated wastewater (e.g., acetaminophen, N,N,diethyl-meta-toluamide [DEET], and gemfibrozil) were less than 10% of established thresholds. Attenuation of target CECs was not observed downstream of WRP discharge until dilution by seawater occurred in the tidal zone, partly because of the short hydraulic residence times in these highly channelized systems (<3 d). In addition to confirming CECs for future in-stream monitoring, these results suggest that conservative mass transport is an important boundary condition for assessment of the input, fate, and effects of CECs in estuaries at the bottom of these watersheds. © 2013 SETAC.

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