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Newport News, VA, United States

Roth D.K.,Washington Technology | Cornwell D.A.,Environmental Engineering and Technology Inc. | Carpenter A.T.,AWWA Government Affairs Office
Journal - American Water Works Association | Year: 2015

The US Environmental Protection Agency has identified carcinogenic volatile organic compounds (cVOCs) as the first group to be regulated as part of the agency's new strategy to regulate contaminants as a group. The structure of a cVOC group rule has not been published, but the US Environmental Protection Agency has identified two potential approaches: (1) establishing a group maximum contaminant level that is based on the sum of contaminant concentrations or (2) establishing a group maximum contaminant level that is based on the sum risk-weighted contaminant concentrations. Working from these two approaches, the AWWA cVOC Workgroup has developed six potential regulatory scenarios for a group cVOC rule. Case studies of two Long Island, N.Y., utilities were conducted using historical data from those utilities' existing packed tower aeration treatment systems. The performance of the existing packed tower aeration treatment systems when treating historical peak cVOC influent concentrations was modeled to determine compliance with the six potential regulatory scenarios. © 2015 American Water Works Association. Source


Roth D.K.,Washington Technology | Cornwell D.A.,Environmental Engineering and Technology Inc. | Carpenter A.T.,AWWA Government Affairs Office | Roberson J.A.,AWWA Government Affairs Office
Journal - American Water Works Association | Year: 2015

The US Environmental Protection Agency has identified carcinogenic volatile organic compounds (cVOCs) as the first group to be regulated under its new strategy for addressing contaminants as groups. Should this potential regulation be promulgated, utilities that currently do not treat for VOCs may need to implement best available technologies (BATs) for removing cVOCs. Utilities that currently treat for VOCs may need to improve or add BATs to ensure adequate treatment under the potential regulation. This article presents decision trees to assist utilities in selecting BATs on the basis of their particular groundwater source. The researchers contacted manufacturers of selected BAT equipment such as low-profile aeration systems and granular activated carbon systems to obtain information on equipment footprints and costs for a range of flow rates and VOC removal rates. This information was used to project capital and operating costs as well as space requirements for those BATs. © 2015 American Water Works Association. Source


Graf K.C.,University of Florida | Cornwell D.A.,Environmental Engineering and Technology Inc. | Boyer T.H.,University of Florida
Separation and Purification Technology | Year: 2014

The goal of this research was to use bench-scale testing to simulate a two-stage countercurrent sorption process for the removal of dissolved organic carbon (DOC) using a variety of sorbents including magnetic ion exchange (MIEX) resin, anion exchange resin (AER), granular activated carbon (GAC), and powdered activated carbon (PAC). Preliminary experiments used surface water from the St. Johns River (SJR), FL, USA with raw water DOC of 7.4-27.5 mg/L. Preliminary experiments investigated each sorbent at four different mixing speeds and five different contact times. MIEX resin, AERs, GACs, and PAC showed 54%, 20-30%, 5-10%, and 20% DOC removal at a 30 min contact time in preliminary kinetic experiments. DOC removal by the AERs and activated carbons was lower than by the MIEX resin even though the AERs and activated carbons had higher capacity than the MIEX resin. MIEX resin, PFA444 AER, and F400 GAC were selected for additional testing using the SJR water and a surface water from Virginia (VA), USA, which had an average DOC of 3.2 mg/L. Two hour uptake experiments using MIEX, PFA444, and F400 and SJR and VA waters were used to calculate the sorbent dose necessary for 99% removal of the adsorbable fraction of DOC in a two-stage countercurrent process. Finally, bench-scale tests were conducted using MIEX, PFA444, and F400 and SJR and VA waters to simulate the two-stage countercurrent process using the doses calculated from the 2 h uptake experiments. The average two-stage removal of the adsorbable fraction of DOC in SJR water and VA water for F400, PFA444, and MIEX were 109% and 84%, 90% and 88%, and 85% and 94%, respectively. The results showed that the 2 h uptakes experiments and calculations were satisfactory in predicting the doses and corresponding DOC removal in the two-stage countercurrent process. © 2013 Elsevier B.V. All rights reserved. Source


Ishii S.K.L.,University of Florida | Boyer T.H.,Environmental Engineering and Technology Inc. | Cornwell D.A.,Environmental Engineering and Technology Inc. | Via S.H.,AWWA Government Affairs Office
Journal - American Water Works Association | Year: 2015

This work is motivated by technical advancements related to direct potable reuse (DPR) and the importance of public values when considering alternative water resources. This study involved the distribution of an online survey to residents in four US cities about existing tap water supplies and "purified water," defined as "municipal wastewater that has undergone advanced water treatment processes, thus resulting in water quality that, at a minimum, complies with drinking water regulations." Overall, 50-60% of respondents were in support of using purified water as potable water. Contaminant concerns were highest for taste/smell and microbial contaminants in both current tap water and purified water. Survey results highlight the importance of addressing certain areas when communicating about DPR to the public, such as barriers against microbial contamination, the trustworthiness of utilities, potential improvements over the status quo, and community-specific drivers that necessitate the use of purified water in a given setting. © 2015 American Water Works Association. Source


Cornwell D.A.,Environmental Engineering and Technology Inc. | Brown R.A.,Environmental Engineering and Technology Inc. | Via S.H.,AWWA
Journal - American Water Works Association | Year: 2016

This article summarizes findings from two AWWA-sponsored surveys of US community water systems (CWSs) that were conducted to gather information on lead-containing service lines (LSLs) in different regions of the United States for different sizes (population ranges) of water systems. The major objective of this research was to estimate the number of water systems with LSLs and the approximate number of LSLs nationwide and by region. These estimates were ultimately extrapolated to state occurrence. The survey results indicated a national estimate of 6.1 million LSLs (either full or partial) currently present in CWSs of the United States, compared with 10.2 million estimated at the time of the original Lead and Copper Rule (LCR) (USEPA 1991); approximately 11,200 CWSs currently have LSLs compared with more than 15,000 estimated in the original LCR; 15 to 22 million people served by CWSs are estimated to have either a full or partial LSL serving their home out of a total population served by CWSs of about 293 million (7%); and approximately 30% of the CWSs surveyed (national average) reported having some LSLs in their system. © 2016 American Water Works Association. Source

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