bluuebunny/crossref_metadata_2025 huggingface dataset:
Ozonation: Assessing Its Role in the Formation and Control of Disinfection By‐products
Authors: Jacangelo Joseph G. , Patania Nancy L. , Reagan Kevin M. , Aieta E. Marco , Krasner Stuart W. , McGuire Michael J.
Published: February 2018

An increasing number of chlorinated by‐products resulting from disinfection practices will be regulated as a result of the 1986 amendments to the Safe Drinking Water Act. Consequently, ozone is being employed more frequently for the control of trihalomethanes and other disinfection by‐products (DBPs). To evaluate the impact of ozonation on the formation and control of DBPs in drinking water, studies were conducted at four utilities. Treatment modifications were made on the process trains at each plant either at full or pilot scale to incorporate ozone in the treatment process. Samples were collected before and after ozone was added to the treatment train and were analyzed for selected DBPs. In general, treatment trains that employed ozonation followed by chloramination were the most effective in reducing trihalomethanes and other halogenated DBPs. Increases were found, however, in some compounds such as chloropicrin and aldehydes.
Surveying an Irish Bar
Authors: Mannion John B.
Published: February 2018

Through a conversation with Harp Nolan and Mick Mahoney at an Irish bar, Mr. Mannion urges participation in the new AWWA utility survey. The data will be used to help supply water utility information to the federal government.
Value of Briskin Interview Challenged
Authors: Kelley William A.
Published: February 2018

William Kelley did not like the JOURNAL (Face to Face, July 1989) giving Jeanne Briskin from EPA space for her views on lead and her draft regulation. He also objects to the last question where she said she thought women's rights questions were involved in some of the lack of acceptance of her draft regulation. Mr. Kelley asks for a response in a future JOURNAL issue from knowledgeable people discussing the pros and cons of technical issues.
Hands Off That Hydra Head!
Authors: Mannion John B.
Published: February 2018

The water industry is faced with conflicting issues (two Hydra heads) concerning asbestos: a suggested health‐based maximum contaminant level in drinking water based on the knowledge that inhaled asbestos is harmful, and those who say that people can safely drink, or ingest, water with asbestos fibers and the US ban on asbestos should not be taken as a rationale for a similar ban elsewhere. This approach has put water utility managers in a difficult position in responding to customers about this issue. Mr. Mannion suggests that, as always, respond honestly and say the rule is a silly embarrassment, will be implemented and the consumer will pay. Mr. Mannion suggests that Congress and regulators would benefit from more balanced information. He also states that the mutually agreed upon goal of safe drinking water for all is difficult to achieve when the industry is forced to cope with false or minor problems, like the asbestos rule.
Committee Report: Membrane Desalting Technologies
Authors:   AWWA Water Desalting and Reuse Committee
Published: February 2018

Many decision‐makers in the water supply field are not familiar with advances in membrane technologies for desalting, softening, trihalomethane precursor removal, and wastewater reuse. Membrane technologies should be considered as a water treatment alternative, particularly when adequate low‐cost freshwater supplies are not available. Two such technologies, reverse osmosis and electrodialysis, are described in this report, as well as system design considerations and costs.
Cost and Performance of a Membrane Pilot Plant
Authors: Taylor James S. , Mulford L.A. , Duranceau S.J. , Barrett W.M.
Published: February 2018

The cost and effectiveness of trihalomethane (THM) control and potable water production by a membrane process were investigated during a one‐year project at Flagler Beach, Fla., where the feedwater was a highly organic groundwater. Results of the study showed that the membrane system could control the formation of THMs for an extended period, producing a finished water that exceeded quality and quantity requirements. Construction and operating costs for a membrane plant at Flagler Beach would be about the same as for a conventional softening plant—but the finished water would be of a superior quality. The membrane plant was observed to be less labor intensive and easier to operate than a softening plant.
Acid‐Base Reactions in Gas Transfer: A Mathematical Approach
Authors: Howe Kerry J. , Lawler Desmond F.
Published: February 2018

Acid‐base reactions occur simultaneously with gas transfer reactions in several common applications in water and wastewater treatment. A simple methodology to account quantitatively for the effects of the acid‐base reactions on the gas transfer rate was developed, checked by comparison with laboratory data, and applied to an actual drinking water problem situation. Equations for application to a variety of gas‐liquid contacting reactors are given. The rate of gas adsorption or stripping was shown to be drastically influenced by pH in applicable cases. Laboratory results for stripping of carbon dioxide in batch reactors and continuous‐flow countercurrent packed towers compared excellently with the theory. The theory was applied to a full‐scale operating system in which hydrogen sulfide is stripped from a groundwater drinking water supply; simultaneous stripping of carbon dioxide and oxidation of the sulfide were accounted for. Reduction of the influent pH was recommended to improve the stripping of the hydrogen sulfide.
Developing an Incentive Program for Field Service Workers
Authors: Grasso Curtis J.
Published: February 2018

The Indianapolis Water Company developed computer software to improve the productivity of its customer service operations. The software measures, routes, schedules, and maps customer field service activities. The software uses customer location, time of day, type of service, and time elements to develop routes that minimize driving distances for service workers. The software also evaluates a worker's job performance by measuring productivity and work quality. It generates daily, weekly, and monthly summary statistics for managers and supervisors. Under this program, worker productivity increased 100 percent and overall mileage dropped 40 percent.
Planning and Analysis for Water Reuse Projects
Authors: Asano Takashi , Mills Richard A.
Published: February 2018

Drought‐induced water shortages and concern for long‐term reliable water supplies are giving impetus to exploring innovative options for water supply. Water pollution control efforts have made available treated effluent, which can be an economical water supply compared with the increasing expense of developing new sources. Poorly conceived planning efforts, however, often lead to the rejection of worthwhile water reclamation and reuse projects or to the implementation of projects that will not achieve the intended goals. This article discusses the critical planning factors in wastewater reclamation and reuse and presents a systematic approach for the successful implementation of water reuse projects.
Eating Anchovies at the Opera
Authors: Mannion John B.
Published: February 2018

Some utilities love National Drinking Water Week and others turn their backs, just like some like eating anchovies and listening to opera and others do not. Two explanations are given for the nonobservers: celebrating Drinking Water Week serves no useful purpose, or the utility might not know how to do the job. The lack of skill can be overcome with the use of the AWWA kit of materials, suggestions and how‐to‐do‐it instructions, and advanced planning and arrangements. The primary purpose of the week is self‐evident–to increase the public's understanding and appreciation of its water service. Experience reveals a secondary benefit: an increase in employee pride. Participation in Drinking Water week is encouraged.
MCL Noncompliance: Is the Laboratory at Fault?
Authors: Koorse Steven J.
Published: February 2018

This article describes the role of the laboratory in developing and determining compliance with maximum contaminant levels (MCLs) under the Safe Drinking Water Act (SDWA). It begins with a brief overview of the pertinent provisions of the SDWA and discusses laboratory performance variability. The article also details how the US Environmental Protection Agency develops MCLs and highlights how laboratory performance variability can impair a water system's ability to comply with those limits. Some suggestions are offered that are designed to help water systems cope with analytical variability in the regulatory process.
Technical Note: Adsorption Capacity of GAC for Synthetic Organics
Authors: Speth Thomas F. , Miltner Richard J.
Published: February 2018

Isotherms are presented for 58 compounds in distilled–deionized water, filtered river water, and filtered groundwater. The compounds, which ranged from volatile organics to insecticides, are either regulated or being considered for regulation by the US Environmental Protection Agency.
Talking Turkey With a Turkey
Authors: Mannion John B.
Published: February 2018

Mr. Mannion responds to complaints about AWWA members and volunteering. He states that AWWA is the creation of the industry and exists because water professionals and water utilities need a forum for common action–a way to do things that an individual or single utility cannot do alone. The economies and technical progress achieved through associations are incalculably greater than any local water utility could accomplish by itself. Mr. Mannion sees professional‐industrial volunteerism not as an act of charity but as enlightened self‐interest, a means of serving a common cause, that also serves one's own interests. He requests encouragement and support for AWWA volunteers.
Radium‐226 and Tritium in Public Well Supplies of the Greater Chicago Area
Authors: Kristoff Ljerka M. , Lordi David T. , Lue‐Hing Cecil
Published: February 2018

Relatively higher levels of total alpha and beta radioactivities encountered in wastewater of one of the wastewater treatment facilities operated by the Metropolitan Water Reclamation District of Greater Chicago prompted a radiological survey of the municipal well water supplies in the region. The concentrations of total alpha activity, total beta activity, and radium‐226 were found to be higher in waters from wells with depths greater than 1,200 ft (366m) than in waters from wells of less than 850 ft (259 m) depth. The waters from 10 of the deep wells were found to contain an unmeasurable concentration of tritium, but all of the shallow‐well waters contained tritium at 0.3 nCi/L.
WaterTech Welcomed
Authors: Buckley Hugh
Published: February 2018

The author welcomes the birth of WaterTech USA (recently renamed Water for People). The author relates that during the International Drinking Water Supply and Sanitation Decade, many wells in developing countries were constructed and equipped with hand pumps that could not be maintained by the communities. Much research, development and intercultural exchange during the next 10 years resulted in the development of simplified hand pumps that are village‐level operation and maintenance (VLOM). As the problems of providing clean water and sanitary conditions in developing countries are being redefined from this experience, the author feels that this is a most opportune time for AWWA, with its resources and large supporting industry, to enter the field.
Reducing Water Demand During Drought Years
Authors: Gilbert Jerome B. , Bishop Walter J. , Weber Jack A.
Published: February 2018

Responding to second and third consecutive drought years, East Bay Municipal Utility District implemented drought programs with mandatory conservation goals by customer group, strict ordinances on water use, an inclining‐block rate structure, and an extensive public relations program. These measures collectively achieved reductions in consumption during the summers of 1988 and 1989 of 30 and 27 percent, respectively, compared with the targeted 25 and 15 percent conservation levels that had been established for these periods.
Measuring Aluminum During Water Treatment: Methodology and Application
Authors: Van Benschoten John E. , Edzwald James K.
Published: February 2018

A method for determining aluminum during water treatment is described. The procedure, which involves filtration and cation exchange to isolate specific aluminum fractions followed by analysis, was applied to two municipal water treatment plants. Results showed that 70‐80 percent of the aluminum present in the treated water was in the dissolved form. Residual aluminum concentrations and the extent of oversaturation were affected by the pH of coagulation, the treated water pH, and temperature.
Slow Sand Filtration in Small Systems in Oregon
Authors: Leland David E. , Damewood Mel
Published: February 2018

Small water systems face immense difficulties in meeting the requirements of the Surface Water Treatment Rule. This article describes partnerships formed between the state regulatory agency, communities, and consulting engineers in Oregon to assist small communities in meeting these requirements. A case study is presented of a small community that successfully installed slow sand filtration, which has proved to be an effective and appropriate treatment technology. Also described are several associated demonstration projects undertaken by state water program staff to develop pilot filter and design guidelines for use in future projects.
Who Reads a Water Quality Report?
Authors: Yoo R. Scott
Published: February 2018

The San Jose Water Co.'s annual water quality report is the cornerstone of the utility's public education program. The report, created in response to news reports about the quality of groundwater in Silicon Valley, attempts to “set the record straight” regarding the quality of water delivered to customers. The report, a bill stuffer, is sent to all customers. It describes water supply sources, treatment processes, and water quality control programs; it also includes a table comparing local water quality with state and federal drinking water standards. The author conducted an informal survey of industry practices concerning water quality reports. All respondents provide some type of water quality data for customers on request, but only 3 percent of regularly distribute such reports to all customers.
Flocculation in Turbulent Flow: Measurement and Modeling of Particle Size Distributions
Authors: Casson Leonard W. , Lawler Desmond F.
Published: February 2018

Fluid motion in an oscillating‐grid flocculator was investigated quantitatively with a laser Doppler velocimeter for two mixing conditions. Batch flocculation experiments were performed for monodisperse, bimodal, and trimodal latex suspensions. The effects of mixing intensity, particle charge, and suspension concentration on the rate of change in particle size distributions were studied. Experimental results indicated that large eddies are relatively unimportant for flocculation and that flocculation is induced by eddies of approximately the same size as the particles. A method for estimating the velocity gradients in eddies of different sizes in the flow was developed and incorporated into an existing mathematical model for flocculation. The predictions of the revised flocculation model were compared with the experimental results and indicated that the velocity gradients of the eddies adequately describe the interparticle contacts resulting from mixing during flocculation.
Toxicology and Drinking Water Regulations
Authors: Pontius Frederick W.
Published: February 2018

Articles in this section of the Journal are dedicated to providing current information about legislative and regulatory developments pertinent to the drinking water industry. They address needs and concerns of water utilities from a practical standpoint; they are not intended to reflect official positions or policies of AWWA. Frederick W. Pontius, AWWA regulatory engineer, prepared this article summarizing US Environmental Protection Agency approaches for establishing drinking water standards based on contaminant toxicology data. He will also coordinate development of future articles. Pontius monitors and evaluates legislation and regulations that affect the water industry, prepares official AWWA statements on drinking water issues, and represents the association at meetings, workshops, and study groups.
Wetlands
Authors: Babcock Hope , Inhoffer Wendell R. , Ellis William B. , Reinert Robert H. , Studt John F. , Stark Kirk , Hall Robert E.
Published: February 2018

This discussion took place in Washington, D.C., July 19, 1990. The moderator was Robert H. Reinert, vice‐president, Malcolm Pirnie, 100 Eisenhower Dr., Paramus, NJ07652. Members of the panel were: Hope Babcock, general counsel, National Audubon Society, 801 Pennsylvania Ave. S.E., Suite 301, Washington, DC 20003; William B. Ellis, principal, vice‐president, and director, McSweeney, Burtch & Crump, 11 S. 12th St., Richmond. VA 23219; Robert E. Hall, intergovernmental affairs coordinator‐federal, Denver Water Department, 1600 W. 12th Ave., Denver, CO 80220; Wendell R. Inhoffer, general superintendent and chief engineer, Passaic Valley Water Commission, 1525 Main Ave., Clifton, NJ 07011; Kirk Stark, environmental scientist, elevated cases team, US Environmental Protection Agency, 401 M St. S. W., Washington, DC 20406; and John F. Studt, chief, regulatory branch, US Army Corps of Engineers, 20 Massachusetts Ave. N.W., Washington, DC 20314‐1000.
Risk Feedback: An Important Step in Risk Communication
Authors: Benjamin Sally L. , Belluck David A.
Published: February 2018

Communicating with citizens about the possible health effects of exposure to environmental contaminants offers government agencies a significant and growing challenge. Interactive risk communication requires a strong risk‐feedback component. Risk feedback is a structured process whereby the agency solicits, receives, and evaluates citizen input for inclusion in a risk‐management plan. Procedures for planning and managing risk feedback are presented, and these techniques are applied to a hypothetical drinking‐water‐contamination situation.
Operator Certification
Authors: Hay Kenneth M. , Lay Trudie , Kerri Kenneth D. , Gault Galen , Moehlman Stephen E. , Fox Larry J. , Schulz Michael
Published: February 2018

This discussion took place June 19, 1990, in Cincinnati, Ohio, at the Annual Conference. Panel moderator was Trudie Lay, AWWA's small systems program manager. Participants were: Larry J. Fox, state program manager, Louisiana Operator Certification, Louisiana Dept. of Health and Hospitals, 325 Loyola Ave, Room 403, New Orleans, LA 70122; Galen Gault, director, Operations & Maintenance Div., Jones & Henry Engineers Inc., 2000 W. Central Ave., Toledo, OH 43606; Kenneth M. Hay, education‐training specialist; US Environmental Protection Agency, 401 M St. S. W., Washington, DC 20460; Kenneth D. Kerri, professor, civil engineering, Office of Water Programs, California State University, 6000 J St., Sacramento. CA 95819; Stephen E. Moehlman, executive director, Association of Boards of Certification, 426$f12 5th St., Ames, IA 50010; and Michael Schulz, head, Training Section, Environment Canada, 3439 River Rd. S., Ottawa, Ontario, Canada K1A 1C8.
Ultrafiltration of Lake Water: Effect of Pretreatment on the Partitioning of Organics, THMFP, and Flux
Authors: Laîné Jean‐Michel , Clark Mark M. , Mallevialle Joël
Published: February 2018

Pretreatment processes consisting of various combinations of coagulation‐flocculation and powdered activated carbon (PAC) adsorption were evaluated for use in ultrafiltration (UF) of a lake water. Permeate quality was judged on the basis of the removal of nonpurgeable organic carbon (NPOC), ultraviolet‐light‐absorbing compounds, turbidity, and trihalomethane (THM) precursors. The development of permeate flux and the flux recovery after backwash were also monitored and modeled with the series resistance model. It was shown that for ultrafiltration to be effective in removing NPOC and THM precursors, pretreatment with PAC is required. Coagulation treatment before UF also results in the removal of more organic matter than by UF alone but appears to be more important in conditioning the filter cake and enhancing flux.
Irish Guilt in Moderation
Authors: Mannion John B.
Published: February 2018

Using a dialogue between two fictional characters, Mannion espouses the benefits of moderation in all things–including regulation and treatment of drinking water.
Federal Groundwater Laws
Authors: Saner Robert J. , Pontius Frederick W.
Published: February 2018

Articles in this section of the Journal are dedicated to providing current information about legislative and regulatory developments pertinent to the drinking water industry. They address needs and concerns of water utilities from a practical standpoint; they are not intended to reflect official positions or policies of AWWA. Robert J. Saner, of the Washington, D.C., law firm White, Fine & Verville, and Frederick W. Pontius, AWWA associate director for regulatory affairs, prepared this summary of existing federal groundwater statutes based on a larger groundwater legislative project conducted by the AWWA Groundwater Protection Technical Advisory Workgroup and financed by the Water Industry Technical Action Fund.
The Impact of Ozonation on Particle Stability and the Removal of TOC and THM Precursors
Authors: Chang S. David , Singer Philip C.
Published: February 2018

Waters from seven utilities that use ozone as a preoxidant were analyzed to determine the impact of ozone on the removal of total organic carbon (TOC) and trihalomethane (THM) precursors and on the collision efficiency factor and electrophoretic mobility of suspended particles in the water. Water quality characteristics that favor the use of ozone as a coagulant aid were identified. Preozonation was shown to lower THM formation potential by about 10 percent at the dosages commonly used in practice, and optimal ozone‐induced particle destabilization was found to occur in waters with hardness‐to‐TOC ratios >25 mg CaCO3/mg C and ozone doses of about 0.4–0.8 mg O3/mg C.
The New Radionuclide Regulations—A Preview
Authors: Pontius Frederick W.
Published: February 2018

Articles in this section of the Journal are dedicated to providing current information about legislative and regulatory developments pertinent to the drinking water industry. They address needs and concerns of water utilities from a practical standpoint; they are not intended to reflect official positions or policies of AWWA. Frederick W. Pontius, associate director for regulatory affairs, prepared this article on the upcoming radionuclide regulations and coordinates development of future articles. Pontius monitors and evaluates legislation and regulations that affect the drinking water industry, prepares official AWWA statements on drinking water issues, and represents the association at meetings, workshops, and study groups.
Radioactivity in Water Treatment Wastes: A USEPA Perspective
Authors: Parrotta Marc J.
Published: February 2018

Radioactive substances, such as radium, in water treatment wastes often result in difficult and confusing situations for those people with responsibility for handling and disposing of the wastes. In 1990, the US Environmental Protection Agency signaled its concern by issuing guidance for the disposal of radionuclide‐bearing wastes and for stemming potential radiation hazards.
THM Formation by the Transfer of Active Chlorine From Monochloramine to Phloroacetophenone
Authors: Topudurti Kirankumar V. , Haas Charles N.
Published: February 2018

The purpose of this study was to investigate whether there is a direct transfer of active chlorine (Cl+) from monochloramine to phloroacetophenone (PAP), leading to the formation of trihalomethanes. The reactions of monochloramine and free chlorine with PAP were studied in batch and flow‐through reactors. Chloroform was found to be formed at neutral pH, primarily as a result of direct transfer of Cl+ from monochloramine to PAP. Although the chloroform concentration was two orders of magnitude less with monochloramine than with free chlorine, monochloramine can still produce significant concentrations of chloroform.
Investigating the Mechanism of Inactivation of Escherichia coli B by Monochloramine
Authors: Jacangelo Joseph G. , Olivieri Vincent P. , Kawata Kazuyoshi
Published: February 2018

To better understand the mode of action of monochloramine, its effect on the structural and physiological integrity of Escherichia coli B was studied. The disinfectant did not severely damage the cell envelope of the bacterium or affect nucleic acid function. Inhibition of typical protein‐associated biological activities, e.g., bacterial transport, respiration, and substrate dehydrogenation, were observed at concentrations normally used for disinfection. Differences in rates of kill and inhibition of various biological activities suggest that the shoulder formation on inactivation curves was due to reactions at many sensitive sites in the bacterium, the extent of which determined whether the organism remained recoverable.
Main Features of Large Water Treatment Plants in Japan
Authors: Kawamura Susumu , Trussell R. Rhodes
Published: February 2018

Japan, one of the most industrialized countries in the world, has water treatment processes that have some unique features. Similar in size and latitude to the state of California, Japan has a population of 120 million people heavily concentrated in large urban areas. Seasonal typhoons, as well as population density, affect the requirements of water treatment. This article summarizes a visit to six treatment plants in the Tokyo and Osaka regions.
Evaluating the Performance of Two Plastic Packings in a Crossflow Aeration Tower
Authors: Little John C. , Selleck Robert E.
Published: February 2018

The gas and liquid resistances to mass transfer were determined for two polypropylene packings placed in an experimental crossflow tower. The results were then compared with corresponding counterflow data as well as with several counterflow mass transfer correlation equations. The liquid‐side mass transfer properties of the two packings proved to he nearly identical for both types of operation, whereas Onda's countertlow gas‐side equation failed to yield accurate results with either mode of operation or packing type. Crossflow air pressure drop gradients were also evaluated, with conflicting results.
Association of Microorganisms With Surfaces in Distribution Systems
Authors: Herson Diane S. , Marshall Dana R. , Baker Katherine H. , Victoreen Hugo T.
Published: February 2018

Studies were conducted with particles obtained from a drinking water distribution system. Upon nutrient addition, both the indigenous attached population of bacteria and added coliforms accumulated in association with the particles. This dramatic increase in numbers of organisms associated with the particles was not reflected in plate counts of the particle‐containing water. These results indicate the potential role of surfaces in harboring organisms that are not detected by sampling the bulk water—until the bacteria are suddenly released into the water.
Effective Revenue Bond Marketing—Put Your Best Foot Forward
Authors: Benson Robert B.
Published: February 2018

Utility administrators trying to control rising costs and rates tend to give little attention to effective revenue bond marketing as a cost‐cutting technique when planning capital improvements. Effective bond marketing involves the process of establishing the optimum debt funding requirements and the subsequent marketing of bonds at the most favorable interest rates. The process requires a clear understanding of the roles of marketing team members and the bond rating process, which are addressed by the author.
Effect of Initial Concentration of a SOC in Natural Water on Its Adsorption by Activated Carbon
Authors: Najm Issam N. , Snoeyink Vernon L. , Richard Yves
Published: February 2018

One of the main factors affecting the equilibrium capacity of activated carbon for synthetic organic chemicals (SOCs) in natural water is the presence of background organic matter (BOM). However, the initial SOC concentration also plays an important role in determining the capacity of the carbon. The objective of this study was to develop a means of quantifying the effect of initial SOC concentration in different types of waters on its adsorption isotherm. The method used approximates the complex mixture of BOM with a single equivalent background compound (EBC). The initial concentration and single‐solute isotherm constants of the EBC were calculated based on the BOM's competitive effect on the adsorption of the SOC on activated carbon. The EBC method was then successfully used to predict the equilibrium capacity of powdered activated carbon for 2,4,6‐trichlorophenol in several natural and finished waters when present at different initial concentrations.
Review of Effects of Silver‐Impregnated Carbon Filters on Microbial Water Quality
Authors: Bell Frank A.
Published: February 2018

The purpose of this article is to examine information regarding the antibacterial characteristics of silver when used in drinking water treatment, available data on bacterial populations in effluents from silver‐impregnated filter units, regulatory and test programs relating to the bacteriostatic action of silver in filters, and recent health effects research.
Standardized Compliance Monitoring
Authors: Pontius Frederick W.
Published: February 2018

Articles in this section of the JOURNAL are dedicated to providing current information about legislative and regulatory developments. They address needs and concerns of water utilities from a practical standpoint; they are not intended to reflect official positions or policies of AWWA. Frederick W. Pontius, AWWA associate director for regulatory affairs, prepared this discussion regarding standardized compliance monitoring and coordinates development of future articles. Pontius monitors and evaluates legislation and regulations that affect the water industry, prepares official AWWA statements on drinking water issues, and represents the association at meetings, workshops, and study groups.
Evaluating Modifications to Slow Sand Filters
Authors: Collins M. Robin , Eighmy T. Taylor , Malley James P.
Published: February 2018

Slow sand filtration may be not only the cheapest and simplest treatment process to operate and maintain but also the most efficient under appropriate circumstances. Limitations of conventional slow sand filters include significant reductions in filter run lengths should raw water turbidity and algal content exceed relatively low levels, poor organic precursor removals, and relatively long filter cleaning downtimes and ripening periods. This review article summarizes and evaluates modifications to slow sand filters that may address these limitations without compromising the simplicity of the treatment process.
Application of Gene Probe Technology to the Water Industry
Authors: Richardson Kenneth J. , Stewart Mic H. , Wolfe Roy L.
Published: February 2018

Recent advances in gene probe technology have provided the water industry with a powerful new technique for monitoring water supplies for an increasingly complex group of microbes. The basic principles of gene probe technology, including gene probe construction, labeling, hybridization, and detection, are summarized. Recent developments such as chemiluminescent detection systems and nucleic acid amplification are outlined. Environmental applications of gene probe technology to microbes of specific interest to the water industry are discussed and compared with traditional detection techniques. Finally, the potential for application of gene probe technology to the water industry is evaluated.
Pilot Testing the Haberer Process in the United States
Authors: Stukenberg John R. , Hesby James C.
Published: February 2018

Perhaps for the first time in the United States, the Haberer process was shown in a Shreveport, La., pilot unit to be capable of flocculating and removing solids from a turbid surface water (contact flocculation) and of simultaneously treating the water with powdered activated carbon (PAC) to remove soluble organic compounds. The overall reduction in trihalomethane formation potential was 63–66 percent when PAC was used in the system, but it is expected that even greater reductions could be achieved if either the type or the dosage of PAC was optimized.
Permeation of Polybutylene Pipe and Gasket Material by Organic Chemicals
Authors: Park Jae K. , Bontoux Laurent , Holsen T.M. , Jenkins D. , Selleck R.E.
Published: February 2018

Recent investigations have found that organic chemicals may contaminate drinking water by permeating buried plastic pipes and gasket materials. Pipe–bottle direct‐exposure experiments and microbalance experiments were conducted in order to determine the susceptibility of polybutylene (PB) piping material and gasket materials to permeation by a wide range of organic chemicals. Many lipophilic compounds tested were found to permeate to a detectable level in consumers' tap water within a month at one third of their aqueous solubilities. It was also found that PB was more permeable than low‐density polyethylene to toluene and that chlorinated hydrocarbons permeated PB faster than unchlorinated hydrocarbons. Gasoline compositions such as benzene, toluene, ethyl benzene, and xylenes appeared to be highly permeable to PB and gasket material. The organic chemicals were approximately 5 to 100 times more permeable in gasket materials than in PB.
Process Selection for Potable Reuse Health Effects Studies
Authors: Lauer William C. , Rogers Stephen E. , LaChance Anthony M. , Nealey Myron K.
Published: February 2018

Denver's direct potable water reuse demonstration project has spanned nearly two decades. Following more than 10 years of pilot study, a 44‐L/s (1‐mgd) treatment plant was constructed to further evaluate the most promising processes to convert unchlorinated secondary wastewater directly to drinking water quality. The $17‐million facility began full operation in 1985 and originally incorporated the following treatment processes: lime clarification, recarbonation, filtration, selective ion exchange with regenerant recovery system, two‐stage activated carbon adsorption with thermal regeneration system, ozonation, reverse osmosis, air stripping, and chlorine dioxide disinfection. During the first two and one‐half years of demonstration plant operation, researchers evaluated three distinct process sequences and numerous process optimization and pilot studies. The culmination of this work was the selection of the treatment process sequence to be used during the remainder of the five‐year project. The health effects treatment sequence was derived following evaluation of the data and consultation with Denver's project advisory committee. The treatment train includes lime clarification (pH 11.0), recarbonation (pH 7.7), filtration, ultraviolet disinfection, activated carbon adsorption (42 minutes of empty bed contact time), reverse osmosis, air stripping, ozonation, and chloramination as a residual disinfectant. Exhaustive testing of this process sequence will be used to compare the quality of direct potable reuse water and Denver's high‐quality drinking water.
Comparative Subchronic Toxicity of Chlorine and Monochloramine in the B6C3F1 Mouse
Authors: Daniel F. Bernard , Ringhand H. Paul , Robinson Merrell , Stober Judy A. , Olson Greg R. , Page Norbert P.
Published: February 2018

Separate groups of male and female B6C3F1 mice were administered chlorine and monochloramine in drinking water for 90 consecutive days. Both disinfectants were supplied at 12.5, 25, 50, 100, and 200 mg/L. Criteria evaluated included mortality, clinical signs, body weight, food consumption, hematology, clinical chemistry, organ weights, gross pathology, and histopathology. Overall, the correlation of the biochemical, hematological, and organ weight data, in the absence of histopathology and observable clinical signs of toxicity, suggests that the chlorine and monochloramine induced effects via an indirect mechanism, e.g., nutritional deficiencies, rather than a direct toxicological effect on specific organs or tissues.
Olson Defends Study Again
Authors: Olson Betty , Clark Debbi
Published: February 2018

Betty Olson, author of research that challenged the efficacy of the Colilert test, defends her research against criticisms from Stephen C. Edberg and Michael Katamay. The criticisms were published in the August 1991 issue of Journal AWWA. This is part of a long‐term dialogue in the letters column, which was sparked by an article (“Update Researcher challenges efficacy of E. coli analytical technology”) that appeared in the September 1990 issue of Journal AWWA. Letters of criticism and Olson's responses were printed in 1991 in the January, March, and August issues of Journal AWWA.
USEPA's Proposed Radon MCL: Too High, Too low, Or Just Right?
Authors: Pontius Frederick W.
Published: February 2018

The U.S. Environmental Protection Agency (USEPA) proposed National Drinking Water Regulations July 18, 1991, for six radionuclides, including radon. One of the more than 600 sets of comments submitted in response to this proposed rule, most focused on radon. Comments are sharply divided over how radon should be regulated in drinking water. Opinions about the most appropriate level for the radon maximum contaminant level (MCL) are widely divergent. An overview of submitted comments regarding the radon MCL and the issues behind the current debate are the focus of this article.
Urban Drought Response in Southern California: 1990–91
Authors: Shaw Douglas T. , Henderson R. Todd , Cardona Martha E.
Published: February 2018

Analysis of weekly water use in Los Angeles and San Diego, California, indicates that drought response programs in both cities achieved 22–25 percent reductions in 1991, despite differences in their respective approaches to conservation. Most of the reductions were achieved during the summer of 1991, but water use even during a late fall wet period continued to be significantly below levels that would have been expected without conservation. It is suggested that more attention be given to actual levels of compliance with water use restrictions than to nominal differences of voluntary versus mandatory conservation.
Developing a Long‐Term Drought Plan for Phoenix
Authors: Dziegielewski Benedykt , Jr. William R. Mee , Larson Keith R.
Published: February 2018

Assessing the economic consequences of potential water supply shortages can help water agencies determine the need for investment in long‐term protection from drought. In Phoenix, Ariz., the risk of drought damage in the long term justifies the need for additional drought protection through developing standby groundwater supplies and implementing permanent demand‐reduction measures. The most efficient way of dealing with the risk of drought in Phoenix is to maintain the existing standby groundwater supplies, add new wells, and develop a moderate, temporary demand‐reduction program. Without reserve wells, the city would have to resort to additional expensive supply acquisitions or very stringent restrictions on water use during periods of severe drought.
Nonresidential Water Conservation: A Good Investment
Authors: Ploeser Jane H. , Pike Charles W. , Kobrick J. Douglas
Published: February 2018

Business and industrial (nonresidential) water conservation is becoming a major area of emphasis for water utilities throughout the United States. Four factors have led to the growth of nonresidential conservation programs: (1) residential customers who have been asked to conserve expect the business community to do its share as well, (2) recent conservation mandates in several states require that conservation programs include all customer types, (3) a relatively small percentage reduction in nonresidential water use constitutes meaningful demand and drought management strategies, and (4) nonresidential water conservation is cost‐effective. Some of the major areas of water use and the best available conservation technologies and their applications in the business, industrial, governmental, and institutional sectors are outlined. Program components used by states and municipalities are discussed, and the trends in nonresidential conservation are examined.
Combining Methods for the Reduction of Oxychlorine Residuals in Drinking Water
Authors: Griese Mark H. , Kaczur Jerry J. , Gordon Gilbert
Published: February 2018

Previous investigations have shown ferrous iron application to be an effective and economically feasible method of removing residual chlorine dioxide and chlorite ion from drinking water. This treatment, however, was not effective in reducing concentrations of chlorate ion. To address this issue, combined methodologies (alternative chlorine dioxide generation and application together with iron reduction) have been developed that significantly reduce finished‐water oxychlorine residuals. These methodologies and the effect of various treatment conditions toward low‐level chlorate ion formation are the focus of this article.
Using Ion Chromatography to Analyze Inorganic Disinfection By‐products
Authors: Hautman Daniel P. , Bolyard Michele
Published: February 2018

Ion chromatography is used to analyze drinking water for inorganic disinfection by‐products—the oxyhalides of chlorine and bromine—following disinfection. A previous study found chlorite ion (ClO2−) to be unstable in drinking water. This investigation focused on stabilizing and preserving ClO2− by studying several agents known to quench its reaction with species present in drinking water. Based on the initial stability study, ethylenediamine was an effective preservative and was further studied using finished water from various utilities. Also, the measurement of bromate following ozonation of a river water matrix containing 0.037 mg Br−/L is illustrated.
Comparison of the Microextraction Procedure and Method 552 for the Analysis of HAAs and Chlorophenols
Authors: Barth Robert C. , Fair Patricia Snyder
Published: February 2018

A comparison of the accuracy, precision, and detection limits of two methods for determining the concentrations of haloacetic acids and chlorophenols in drinking water is presented. Both methods consist of liquid–liquid extraction of the water sample with methyl‐tertiary‐butyl ether, diazomethane derivatization of the extracts, and analysis by gas chromatography (GC) with electron capture detection. Method 552, developed by the US Environmental Protection Agency, and a microextraction method, developed by the Metropolitan Water District of Southern California, gave comparable precision and method detection limits in fortified reagent water and the drinking‐water samples examined in this study. The microextraction method provided greater accuracy in routine applications because of the use of procedural standards for GC calibration. Because the microextraction method is also less labor‐intensive, it is preferred in most drinking‐water applications.
Pilot Study of the Effects of Ozone and PEROXONE on In‐line Direct Filtration
Authors: Tobiason John E. , Edzwald James K. , Schneider Orren D. , Fox Michael B. , Dunn Howard J.
Published: February 2018

The effects of preoxidation with ozone and PEROXONE (hydrogen peroxide and ozone) on in‐line filtration performance were examined by conducting pilot‐scale experiments and comparing the results with full‐scale plant performance. Preoxidation did not allow for a reduction in coagulant (combined alum and cationic polymer) doses for good treatment yet sometimes caused increased filter run lengths because of lower head loss or delayed turbidity breakthrough. Filter effluent turbidities were similar for no‐oxidant and preoxidant trains. Dissolved organic carbon levels in filtered waters were higher for the preoxidation train as compared with no preoxidation. PEROXONE was moderately more effective than ozone alone in eliminating odors in filtered waters.
DBP Control by Nanofiltration: Cost and Performance
Authors: Blau Trisha J. , Taylor James S. , Morris Kevin E. , Mulford L.A.
Published: February 2018

A nanofiltration membrane pilot plant was operated for one year at the Daytona Beach, Fla., Brennan water treatment plant. During that year, the pilot plant was evaluated for disinfection by‐product control and water production. This article discusses selection of the membranes and the quality of the water they produced, along with cost estimates for a 10‐mgd groundwater nanofiltration plant.
Creating a High‐Performance Utility: The Link Between Culture and Organizational Health
Authors: Marlowe Herbert A. , Beaudet Bevin A.
Published: February 2018

Organizational culture has been related to organizational performance in a number of nonutility settings. In this study, actual and desired cultures of a water utility were analyzed along with data on measures of organizational health. The major finding was that the greater the discrepancy between actual and ideal cultures, the lower the level of job satisfaction, the less the degree of job involvement, and the lower the level of commitment to the organization. Implications of these and other findings for utility management are discussed.
SOC Removal in a Membrane Softening Process
Authors: Duranceau Steven J. , Taylor James S. , Mulford Luke A.
Published: February 2018

The authors investigated the rejection of six synthetic organic chemicals (SOCs) in a potable water source by a nanofiltration membrane softening process. Each SOC was studied separately for one month—which was subdivided into four recovery periods. The four largest‐molecular‐weight compounds (chlordane, heptachlor, methoxychlor, and alachlor) were completely rejected by the membrane. Ethylene dibromide, the lowest‐molecular‐weight compound studied, was not rejected by the membrane, whereas dibromochloropropane was partially rejected. Mass balances indicated that SOC recovery decreased as SOC molecular weight (MW) increased, which suggested that the three largest‐MW SOCs had been adsorbed by the membrane. The percentage of SOC rejection increased as MW increased, and the rejection of inorganic solutes increased as MW and species charge increased. No effect on solute mass transfer of any solutes resulted from membrane feed‐stream velocities, which were estimated to vary from 0.19 to 0.52 fps.
Mass Transport Considerations for Pressure‐Driven Membrane Processes
Authors: Wiesner Mark R. , Chellam Shankararaman
Published: February 2018

Numerical simulations and experimental work for evaluating transport mechanisms for colloidal foulants in pressure‐driven membrane systems are discussed. A model for concentration polarization is used to explore the role of ionic strength in determining the distribution of dissolved humic materials near a rejecting membrane. Particle trajectory theory predicts that there should exist a critical particle size above which particles will not deposit on the membrane. For conditions typical of ultrafiltration and microfiltration, which operate in laminar flow and utilize an inside‐out geometry, this critical particle diameter is likely to be in the range of 10–50 μm. Qualitative evidence, based on measurements of permeate flux, supports the theoretical minimum in diffusive back‐transport of particles predicted to occur for particles near 0.1 μm in size.
Selective Alum Recovery From Clarifier Sludge
Authors: Sengupta Arup K. , Shi Bo
Published: February 2018

Hoping to save money and to reduce solid waste, water utilities are evaluating various alternatives for the disposal of clarifier sludge containing 30 to 50 percent hydrated aluminum hydroxide. In this work, the authors studied a selective, simple‐to‐operate alum recovery process using composite membranes made of fine particles of chelating polymers entrapped in thin sheets of porous polytetrafluoroethylene. Laboratory studies using the sludge from the Allentown (Pa.) Water Treatment Plant showed that alum can be recovered selectively without any significant carryover of organic matter (trihalomethane precursors), manganese, or other heavy metals into the recovered alum. The composite membrane was quite robust and durable and exhibited a high affinity toward dissolved aluminum.