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Scituate, MA, United States

Soller J.,Soller Environmental LLC | Bartrand T.,Corona Environmental Consulting | Ravenscroft J.,U.S. Environmental Protection Agency | Molina M.,U.S. Environmental Protection Agency | And 4 more authors.
Environmental Modelling and Software | Year: 2015

Scientific evidence supporting recreational water quality benchmarks primarily stems from epidemiological studies conducted at beaches impacted by human fecal sources. Epidemiological studies conducted at locations impacted by non-human faecal sources have provided ambiguous and inconsistent estimates of risk. Quantitative Microbial Risk Assessment (QMRA) is another tool to evaluate potential human health risks from recreational exposures to non-human faecal contamination. The potential risk differential between human and selected non-human faecal sources has been characterized previously for direct deposition of animal feces to water. In this evaluation, we examine the human illness potential from a recreational exposure to freshwater impacted by rainfall-induced runoff containing agricultural animal faecal material. Risks associated with these sources would be at least an order of magnitude lower than the benchmark level of public health protection associated with current US recreational water quality criteria, which are based on contamination from human sewage sources. © 2015 Elsevier Ltd. Source

Dotson A.D.,University of Alaska Anchorage | Westerhoff P.,Arizona State University | Ghosh A.,Corona Environmental Consulting
ACS Symposium Series | Year: 2014

A systematic study of disinfection byproduct (DBP) formation from dissolved organic matter (DOM) of six southwestern water samples, three of which were collected during climatic events was performed. DOM was evaluated in its natural state in whole water samples and in a fractionated state where the DOM was isolated through concentration and resin fractionation. Study included evaluation of DBP formation at 1 hour and 7 days during a DBP formation potential test to elucidate the rate of DOM reactivity. Additionally, fractionated DOM was isolated in a manner such that mathematical reconstruction of whole water DBP formation was possible using the results of individual DOM fraction DBP formation potential tests. © 2014 American Chemical Society. Source

McGuire M.J.,Michael J. McCuirc Inc. | Suffet I.H.,University of California at Los Angeles | Rosen J.,Corona Environmental Consulting
Journal - American Water Works Association | Year: 2014

On fan, 9,2014, a spill of "crude" 4-methylcyclohexanemethanol (MCHM) into the Elk River in West Virginia contaminated the water supply for 300,000 people. Ehe crude MCHM caused an intense licorice odor in the drinking water that supplied the area in and around Charleston, W.Va. A sensitive analytical method developed by a commercial laboratory was used to verify the concentrations of crude MCHM presented to a consumer panel selected using specific criteria. The method used for the panel studies was ASTM E679-04, which has been used to determine other odor thresholds in water. The odor threshold and odor recognition concentrations for crude MCHM in water were estimated by the consumer panel to be 0.55 and 7.4 μg/L, respectively. Two estimates of the odor objection concentration were 7.7 and 8.8 μg/L. © 2014 American Water Works Association. Source

Li X.,University of California at Davis | Green P.G.,University of California at Davis | Seidel C.,Corona Environmental Consulting | Gorman C.,Corona Environmental Consulting | Darby J.L.,University of California at Davis
Journal - American Water Works Association | Year: 2016

Regeneration of strong base anion (SBA) exchange resin produces concentrated and hazardous brine. In this research, one alternative regenerant and two brine treatment options were investigated to reduce the hazardous characteristics of the brine. These options included replacing sodium chloride with sodium bicarbonate as the regenerant, using ferrous sulfate (FeSO4) to reduce/coagulate hexavalent chromium (CrVI) in the brine, and applying weak base anion (WBA) exchange resin and chemical reductive media (CRM) to adsorb/reduce CrVI. It was found that bicarbonate was as effective as chloride in regenerating chromium-saturated resins, and the affinity of the bicarbonate-form resin for chromium was similar to that of the chloride-form resin. It was observed that FeSO4 applied at doses close to the stoichiometric ratio achieved almost complete removal of total chromium from the SBA brine. In column tests, two CRM exhibited more than 20 times greater removal capacity for total chromium than did the WBA exchange resins. © 2016 American Water Works Association. Source

Soller J.A.,Soller Environmental LLC | Eftim S.,ICF International | Wade T.J.,U.S. Environmental Protection Agency | Ichida A.M.,ICF International | And 6 more authors.
Microbial Risk Analysis | Year: 2016

We conducted a supplemental water quality monitoring study and quantitative microbial risk assessment (QMRA) to complement the United States environmental protection agency's (U.S. EPA) National Epidemiological and Environmental Assessment of Recreational water study at Boquerón beach in Puerto Rico to estimate the gastrointestinal (GI) illness levels associated with recreational water exposures. The previously reported epidemiological study had sufficient statistical power to detect an average illness rate of approximately 17 swimming associated GI illnesses per 1000 recreation events or greater, and found no consistent relationships between water quality measured by fecal indicator organisms (FIO) and swimming-associated illnesses (U.S. EPA, 2010a). The QMRA incorporated monitoring data for pathogens and fecal indicators collected during the epidemiological study period and calculated average swimming-associated illness levels that were approximately two GI illnesses per 1000 recreation events. To our knowledge, this is the first time that a comprehensive water quality monitoring program and QMRA analysis has been conducted in parallel with a recreational water epidemiological study. The QMRA results were consistent with the low rate of reported illnesses during the 2009 epidemiological study (i.e. <17 GI illnesses per 1000 recreation events) and provide additional context for understanding the epidemiological results. The results illustrate that coupling QMRA with an epidemiological study at a single study site provides a unique ability to understand human health illnesses especially under conditions where water quality, as measured by traditional FIO is good and/or average illness rates are lower than can be quantified via epidemiological methods alone. © 2015 Elsevier B.V. Source

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