bluuebunny/crossref_metadata_2025 huggingface dataset:
USEPA Implements Stormwater Regulations
Authors: Scharfenaker Mark A.
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. Mark Scharfenaker, who wrote this month's article on stormwater regulations, is a contributing editor of the Journal.
Performance Chart Increases Crew Productivity
Authors: Siu Stanley Y.
Published: February 2018

Productivity management plays an important role in the improvement of quality of service and efficiency in public works. This study describes the water crew performance chart, a simple productivity measurement method that was developed in Winnipeg's Operations Department. Using a simple formula, maintenance crew supervisors calculate the productivity index of their crews and plot the results on the chart daily. Since 1987, when use of the chart began, productivity of crews has increased. Management sees the chart as a way workers can get daily feedback on what they do. Deviation from typical performance is easier to detect, and crew members are motivated to improve their performance.
Removing Lead From Drinking Water With a Point‐of‐Use GAC Fixed‐Bed Adsorber
Authors: Kuennen Roy W. , Taylor Roy M. , Van Dyke Karl , Groenevelt Kevin
Published: February 2018

An evaluation was carried out of a point‐of‐use (POU) granular activated carbon (GAG) fixed‐bed adsorber (FBA) for removing soluble and insoluble lead from drinking water. Several factors affected the removal of lead from water by GAC, including carbon type, particle size distribution, solution pH, contact time of water with GAC, surface loading of lead onto GAC, competitive interactions with other heavy metals, and the design of the POU–GAC–FBA. Minicolumns were used to determine the relative capacities of GAG for lead under varying water conditions and to help identify mechanisms of lead removal.
Small Water Systems at a Crossroads
Authors: Cromwell John E. , Harner Water L. , Africa Jay C. , Schmidt J. Stephen
Published: February 2018

Owners and customers of small water systems are at a crossroads. They will soon face the need to make significant investments and bear much greater operating costs to comply with increasingly stringent performance requirements under the Safe Drinking Water Act. Meeting thest demands will expose additional needs to replace deteriorate infrastructurs. A piecemeal approach to coping with the new environment could become a trap if the full scope of these liabilities is not appreciated at the outset. By taking a comprehensive view, systems can either find the assurance they need to move forward confidently on their own or discover restructuring opportunities involving alternative structural or institutional arrangements. This article describes the strategy adopted by Pennsylvania to improve visibility and thereby enhance the viability of small systems.
Removing Natural Organic Matter by Conventional Slow Sand Filtration
Authors: Collins M. Robin , Eighmy T. Taylor , Fenstermacher James M. , Spanos Stergios K.
Published: February 2018

This article evaluates the capacity of slow sand filters to remove natural organic matter (NOM) and organic precursor materials as quantified by dissolved organic carbon, UV absorbance, and trihalomethane formation potential from source waters with varying levels of NOM. Municipal facilities were sampled to provide baseline data and to evaluate the effects of two different filter cleaning techniques, normal scraping and harrowing, on NOM and particulate removal. Pilot‐scale filter studies were conducted to evaluate the influence of two different flow rates on NOM removal, particulate removal, and filter biomass development.
Meeting the Monitoring Challenges of the Lead and Copper Rule
Authors: Frey Michelle
Published: February 2018

Michelle Frey is a civil engineer with Black & Veatch, 1500 Meadow Lane Parkway, Kansas City, MO 64114. A member of the AWWA Water Utility Council's Technical Advisory Workgroup on pesticides and synthetic organic chemicals, she was formerly a member of the staff of AWWA's Government Affairs Office in Washington, D.C.
USEPA's Ban on Asbestos‐Containing Products Invalidated
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 asbestos and coordinates development of future articles.
Animation and Visualization of Water Quality in Distribution Systems
Authors: Deininger Rolf A. , Clark Robert M. , Hess Alan F. , Bernstam Elmer V.
Published: February 2018

Water may undergo a number of changes in the distribution system, making the quality of the water at the customer's tap different from the quality of the water that leaves the treatment plant. Such changes in quality may be caused by chemical or biological variations or by a loss of system integrity. A computer‐visualization technique, coupled with a dynamic water quality model for analyzing spatial and temporal water quality variations, was studied at two systems.
Developing and Utilizing Data Bases for Water Main Rehabilitation
Authors: Habibian Ahmad
Published: February 2018

Managing the maintenance and rehabilitation of a water distribution network can be greatly improved with the aid of an automated data‐manipulating system. The building blocks of a data‐base system are described in this article. When appropriate, examples are cited from the practical experience of the Washington Suburban Sanitary Commission.
Procedure for Preserving Lead in Drinking Water Samples
Authors: Feldmann Charles R. , Walasek James B. , Lobring Larry B.
Published: February 2018

The US Environmental Protection Agency's requirement that drinking water samples collected for lead analysis be acidified at the time of collection poses two problems: (1) restrictions on mailing nitric acid and (2) safety concerns associated with the possible handling of nitric acid by nontechnical persons. A study was undertaken that showed that acidification could be delayed up to 14 days and that analysis could then be carried out after waiting 28 h, without loss of lead.
Quality Is Defined by the Customer
Authors: Reinert Robert H.
Published: February 2018

The author argues that water industry personnel must move from being scientists and technicians in a defensive stance to customer service providers who promote quality drinking water. The water industry must answer customer concerns about water quality with redoubled efforts to improve quality and also involve customers in decisions that affect the quantity and quality of water.
New Regs Set for Phase V Contaminants
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 the Phase V Rule.
Compact Treatment Plant Layout
Authors: Corbin Darryl J. , Monk Robert D.G. , Hoffman Cynthia J. , Crumb S. Frank
Published: February 2018

One of the last steps in the preliminary design of a treatment plant is to develop the plant layout. By this stage of the design process, the site has been selected, the treatment processes have been identified, and the approximate dimensions of the process units have normally been established. The engineer then must arrange the process units on the site. There are a number of alternative basic plant layouts. The particular plant layout selected can have a significant effect on construction cost, hydraulics, plant performance, operation and maintenance (O&M), and ease of expansion. This article describes a compact plant layout that simplifies O&M and minimizes construction cost.
Intake Modeling Yields Significant Savings
Authors: Montgomery Brad
Published: February 2018

Increased system demands and maintenance requirements dictated that the Kentucky‐American Water Company expand one of its intake facilities. Because the utility did not have the operational flexibility or pumping capacity to vary flow rates or remove the pump station or individual pumps from service, model studies were conducted to determine what measures needed to be taken to operate new intake pumps at maximum efficiency during the lowest river water levels. These studies eliminated the need for major structural renovation or replacement of the intake.
Estimating Costs for Treatment Plant Construction
Authors: Qasim Syed R. , Lim Siang W. (Daniel) , Motley Edward M. , Heung Kim G.
Published: February 2018

Preliminary cost estimates can be used to compare the economics of various treatment processes or the costs of major project components. Such estimates do not, however, represent the actual construction and operation and maintenance costs of the project. Actual project costs are site‐specific, cannot be generalized, and must be developed for individual circumstances.
Avoiding Litigation and Preserving Public Confidence Through Compliance Auditing
Authors: Koorse Steven J.
Published: February 2018

This article encourages water suppliers to engage in a systematic compliance evaluation of their operations with respect to the host of environmental laws and regulations to which they are subject. The article begins with an overview of the compliance auditing process and then discusses its potential benefits. A description is given of the auditing procedure and how it can be tailored to fit the needs of individual water systems.
Effect of Separation Processes on the Formation of Brominated THMs
Authors: Summers R. Scott , Benz Mathias A. , Shukairy Hiba M. , Cummings Laura
Published: February 2018

Separation treatment processes are being investigated as a way to control the formation of disinfection by‐products (DBPs) in finished waters. These processes remove natural organic matter before a disinfectant is applied, thus limiting the amount of material available to form DBPs. Four separation processes were examined in this study—granular activated carbon adsorption, powdered activated carbon adsorption, anion exchange, and membrane filtration—using two waters. Results showed that (1) as the dissolved organic carbon (DOC) decreased, the chlorination of diluted organic matter solutions held at constant bromide concentrations yielded a shift to brominated trihalomethanes (THMs); (2) at low DOC concentrations, the percentage of formed brominated trihalomethanes was higher in treated effluent than in influent water; and (3) the processes were most effective for controlling the formation of chloroform and least effective for controlling the formation of bromoform. Based on these results, it can be concluded that effective control of brominated THMs by these separation processes may be difficult for waters containing significant concentrations of bromide.
Determining Beryllium in Drinking Water by Graphite Furnace Atomic Absorption Spectroscopy
Authors: Lytle Darren A. , Schock Michael R. , Dues Nicholas R. , Doerger James U.
Published: February 2018

A direct graphite furnace atomic absorption spectroscopy method for the analysis of beryllium in drinking water has been derived from a method for determining beryllium in urine. Ammonium phosphomolybdate and ascorbic acid were employed as matrix modifiers. The matrix modifiers successfully eliminated common chemical interferences in water samples analyzed for beryllium content, as well as interferences encountered during jar testing of beryllium removal by alum coagulation. The method proved to be a simple, accurate, and precise alternative to the method of standard additions. Method detection limit was 0.03 μg/L, with a linear calibration range of 0–6 μg/L.
Improving the Disinfection Detention Time of a Water Plant Clearwell
Authors: Bishop Mark M. , Morgan J. Mark , Cornwell Brendon , Jamison Donald K.
Published: February 2018

Disinfection detention time, one of the key factors in determining compliance with the Surface Water Treatment Rule, was evaluated in this study to determine (1) whether typical water plant basins can be modified with intrabasin baffles to improve detention time and (2) whether model basins can simulate full‐scale systems. The results of the work show that both a rectangular and a circular basin can be modeled quite accurately by small‐scale basins. Tracer tests showed that T10 detention time can be improved with simple intrabasin baffle walls to approximately 60 percent of theoretical detention time.
The Creative Organization
Authors: Gerstberger Richard L.
Published: February 2018

The truly creative organization is one that integrates the concepts of total quality and empowerment. It is founded on the concepts of continuous improvement and continual innovation, is guided by the clear anticipation of customer wants and needs, and develops a sense of commitment and team spirit throughout the organization that supports self‐responsibility and personal growth and development.
Effect of Ozone Dosage and Subsequent Biodegradation on Removal of DBP Precursors
Authors: Jr. Gerald E. Speitel , Symons James M. , Diehl Alicia C. , Sorensen Harvey W. , Cipparone Lori A.
Published: February 2018

Batch experiments with two Texas surface waters were employed to study the removal of the precursors of trihalomethanes (THMs) and haloacetic acids (HAAs) by ozonation alone and with subsequent biodegradation. Ozone doses of 0.5 to 5 mg/mg total organic carbon (TOC) were tested. Little biodegradation of THM precursors occurred in the absence of preozonation, whereas 25–30 percent of HAA precursors were biodegraded without ozonation. Ozonation and biodegradation combined removed up to 50 percent of THM precursors and up to 70 percent of HAA precursors. In some cases, ozone dosages larger than that now used in practice (1 mg/mg TOC) enhanced removal by the two processes combined. HAA precursors appeared to be more biodegradable than THM precursors, and ozonation enhanced HAA precursor biodegradation more than precursor biodegradation
Committee Report: Research Needs for Inorganic Contaminants
Authors: Committee Inorganic Contaminants Research
Published: February 2018

This report discusses research needs for specific inorganic contaminants of concern to the water industry. Aluminum, arsenic and selenium, bromide, iron and manganese, nitrate, and radionuclides are examined in terms of their significance and occurrence. The types of conventional and emerging treatment technologies used to reduce concentrations of these contaminants in water supplies are identified.
A Cryptosporidiosis Outbreak in a Filtered‐Water Supply
Authors: Leland Dave , McAnulty Jeremy , Keene William , Stevens Gary
Published: February 2018

From January to June 1992, a large outbreak of cryptosporidiosis occurred in Jackson County, Oregon. Epidemiologic investigations associated 43 cases of cryptosporidiosis with the drinking water system in the small community of Talent, Ore. Mechanical and operational deficiencies at one of the city's water filtration plants along with unusually poor raw‐water supply conditions because of low stream flows were possible cocauses of the outbreak. Correction of the deficiencies in the filter plant resulted in substantial improvement in treated‐water quality, and this improvement coincided with the end of the Talent‐related outbreak.
Computerized Corrosion Control
Authors: Rothberg Michael R. , Scuras Sean E. , Leonardo Don , Hale Jess
Published: February 2018

One of the problems with implementing corrosion control has been the difficulty in designing a comprehensive control strategy. The Rothberg, Tamburini & Winsor Model for Corrosion Control and Process Chemistry is a microcomputer spreadsheet‐based tool developed to provide the same information as Caldwell‐Lawrence (C‐L) diagrams regarding pH and CaCO3 equilibrium. To overcome the drawbacks of the diagrams, the model provides a numerical solution based on a specific user's water characteristics and can quickly analyze alternatives. Multiple chemicals can be evaluated simultaneously.
Planning a Distribution System Flushing Program
Authors: Chaddeton Ronald A. , Christensen G. Lee , Henry‐Unrath Patricia
Published: February 2018

The main objective of flushing distribution systems is to improve water quality and service. Flushing programs preserve and improve water quality and control bacterial growth. An effective flushing program anticipates and prevents water quality problems and customer complaints. The fundamental mechanics of flushing are well defined, but little has been known about how to evaluate or optimize the effectiveness of flushing programs. More than half the utilities surveyed for this article have flushing programs and use customer complaints to locate problems in the distribution system. A spreadsheet was used to order areas within a distribution system by flushing priority on the basis of complaint data. Each area could be flushed in anticipation of the peak of complaints. A general planning method or protocol was developed to assist with program organization and analysis. A review of a flushing program conducted by the Philadelphia Suburban Water Company is included.
Nitrification in a Distribution System
Authors: Skadsen Janice
Published: February 2018

Symptoms indicative of nitrification occurred in the Ann Arbor, Mich., system during the late summer of 1990. The episode was characterized by decreases in monochloramine residual and increases in heterotrophic plate count (HPC) bacteria and nitrite. The cause of the nitrification was most probably a high dosage of ammonia combined with granular activated carbon filtration and discontinuation of the hydrant flushing program. The incident was ultimately halted by free chlorination of the distribution system. During free chlorination, an unexpected increase in HPC bacteria was observed in areas not affected by nitrification. Recommendations for future control of nitrification include more stringent control of ammonia, increased monitoring of nitrite and nitrate, development and implementation of a hydrant flushing program, and experimentation with the effects of pH.
Investigating the Preferential Dissolution of Lead From Solder Particulates
Authors: Lytle Darren A. , Shock Michael R. , Dues Nick R. , Clark Patrick J.
Published: February 2018

During a building corrosion control study, bottles containing acid‐preserved water samples with high levels of lead often had particulate material on the bottom. Scanning electron microscope analysis of the particles showed the presence of tin and the absence of lead, indicating the probable source of lead to be lead–tin solder. A leaching study was done to investigate the effectiveness of the standard 0.15 percent nitric acid preservation procedure for dissolving lead corrosion by‐products. Results indicate that the technique was adequate for dissolving lead from lead–tin solder particles but not for tin.
Laboratory Management: Facing the Challenges of the Future
Authors: Davis Marshall K. , Wolfe Roy L.
Published: February 2018

In a sluggish economy and facing demands for higher productivity, better quality, and improved service, laboratory managers must examine the effectiveness of laboratory operating procedures as well as management practices. The Water Quality Division of the Metropolitan Water District of Southern California (MWD) is substantially changing its approach to management and laboratory operations to address the new challenges that face environmental laboratories in the 1990s. These changes involve strategic planning, implementation of time tracking and productivity measurements, and use of more progressive management concepts such as total quality management (TQM).
Quality Assurance and Quality Control for Drinking Water Laboratories
Authors: Winter John A. , Budde William L. , Novielli Frank
Published: February 2018

Soon after the US Environmental Protection Agency (USEPA) was formed in 1972, agency administrators realized that in order to make appropriate decisions for environmental regulation, they must be assured that data being generated by the agency and the 50 states were valid and legally defensible. Thus in 1979, USEPA established a mandatory quality assurance (QA) program for all data generated by or for the agency. QA responsibilities were assigned to the Office of Research and Development. QA guidance in water chemistry and microbiology was assigned to the Environmental Monitoring Systems Laboratory (EMSL) in Cincinnati, Ohio, and QA guidance in water radiochemistry became the responsibility of the EMSL in Las Vegas, Nev.
Controlling the Formation of Chlorate Ion in Liquid Hypochlorite Feedstocks
Authors: Gordon Gilbert , Adam Luke C. , Bubnis Bernard P. , Hoyt Brian , Gillette Stephen J. , Wilczak Andrzej
Published: February 2018

Experiments were carried out to confirm the presence of chlorate ion (ClO3−) in the treated water of utilities that use hypochlorination. Sixteen commercially produced, concentrated liquid hypochlorite feedstocks were analyzed for ClO3−, and levels as high as 158 g percent ClO3− relative to hypochlorite ion were measured. Finished‐water samples from the utilities surveyed contained as much as 0.30 mg ClO3−/L, primarily the result of decomposition of the liquid hypochlorite feedstocks. Although both dilution and lower temperatures can be effective in minimizing ClO3− formation, it was observed that diluting the initial liquid hypochlorite concentration by a factor of 2 is more effective than decreasing the temperature from 24 to 10°C. A methodology is proposed that predicts the dilution or temperature reduction (or both) required to avoid significant ClO3− formation in the feedstock solutions.
The Occurrence of DBPs in Utah Drinking Waters
Authors: Nieminski Eva C. , Chaudhuri Sanwat , Lamoreaux Terry
Published: February 2018

Disinfection by‐products (DBPs) in water treatment facilities in Utah were studied to determine their occurrence and to evaluate the correlation between levels of trihalomethanes (THMs) and other DBPs. Water samples from 14 medium and large treatment plants and 21 small plants were analyzed for DBPs at three times: as instantaneous formation, at the longest retention time in the distribution system, and as seven‐day formation potential. THMs in plant effluents accounted for 64 percent (weight basis) of all DBPs measured, whereas haloacetic acids accounted for 30 percent, haloacetonitriles 3 percent, haloketones 2 percent, and 2,4,6‐trichlorophenol and chloropicrin traces. The formation of all measured DBPs except trichlorophenol increased with the simulated distribution holding time. Chlorate was found (at $50 μg/L) in finished waters that had been disinfected with liquid chlorine.
Probabilistic Evaluation of Packed‐Tower Aeration Designs for VOC Removal
Authors: Freiburger Eric J. , Jacobs Timothy L. , Ball William P.
Published: February 2018

The design of packed towers for the removal of volatile organic chemicals (WCs) depends strongly on compound volatility and rates of mass transfer. Uncertainty in Henry's constant and mass transfer coefficients greatly affects the predicted performance of completed packed‐tower treatment systems. This research focuses on evaluating the reliability of packed‐tower aeration designs by modeling Henry's constant and mass transfer coefficients as random variables with established distributions using Monte Carlo simulation. A case study consisting of alternative designs to achieve a given required contaminant removal is presented to show how design parameter uncertainty affects the predicted system performance and the cost of resulting designs. It was demonstrated that the probability of failure is an important design consideration in addition to cost and that full consideration of design alternatives will include design parameters outside of those that offer a given deterministically predicted performance.
Using a Hydraulic Model to Predict Hollow‐Fiber UF Performance
Authors: Jones Kimberly L. , Odderstol Eric S. , Wetterau Greg E. , Clark Mark M.
Published: February 2018

A hydraulic model was developed to determine all flows and pressures in a continuous‐flow hollow‐fiber ultrafiltration (UF) system. A pilot‐scale UF system was constructed to test the validity of the model. Deionized water was filtered through the system to simulate nonfouling conditions, and two colloidal suspensions of powdered activated carbon and clay simulated fouling conditions. All flows and pressures were continuously logged for later analysis. For fouling conditions, the flux was described by the resistance‐in‐series model, and a relationship was developed to describe the increase in effective membrane resistance as a function of time. This fitted function was then input into the hydraulic model to predict the flows and pressures in the system under nonsteady fouling conditions. For nonfouling and fouling conditions, the predicted flows and pressures correlated well with the system flows and pressures.
Investigating Filter Performance as a Function of the Ratio of Filter Size to Media Size
Authors: Lang John S. , Giron Jonathan J. , Hansen Amy T. , Trussell R. Rhodes , Jr. Willie E. Hodges
Published: February 2018

The size of the filters used in a water treatment pilot study has a big impact on the cost of the pilot facility itself. It has been shown that errors can be avoided by maintaining an adequate ratio between filter column diameter and media diameter (D/d). The purpose of this study was to investigate the effect of this same scaleup parameter on the filtration process itself. Five pilot‐filter columns were operated in parallel with a full‐scale filter. In these tests, (D/d) ranged from 26:1 for the smallest column to 6,000:1 for the full‐scale filter. No significant differences were observed in the mean rate of head loss buildup, the effluent turbidity, or the effluent particle count for any of the filters, although the variance in the estimate of rate of head buildup was much greater for the smallest filter. A D/d ratio of 50 or greater is recommended for most pilot‐filter operations.
Wanted: Intuitive, Strategic Thinkers
Authors: McKeever Jeanne
Published: February 2018

This erratum corrects figure 8 in the article The Occurrence of DBPs in Utah Drinking Waters, which appeared in the September 1993 issue of Journal AWWA.
Working With a Politically Active Community
Authors: Sultan Martin B.
Published: February 2018

Not too many years ago, the public accepted the judgment of engineers and public works officials regarding the need for and the configuration of major public works projects. This faith has since been replaced with skepticism, distrust, environmental activism, and a strong desire to limit government spending. Taken together, these factors demand that special efforts be made when public works projects are planned. This is especially true in a politically active and knowledgeable community such as Fairfax County, Virginia.
Examining the Impact of Aquifer Storage and Recovery on DBRs
Authors: Singer Philip C. , Pyne R. David G. , AVS Mallikarjun , Miller Cass T. , Mojonnier Carolyn
Published: February 2018

The underground storage of treated drinking water results in the elimination of trihalomethanes (THMs) and haloacetic acids (HAAs) produced during treatment and in a decrease in the concentration of residual disinfection by‐product (DBP) precursors. Removal of THMs is associated with denitrifying conditions, whereas HAAs are removed under aerobic conditions. The findings are consistent with a biological mechanism for DBP and DBP precursor removal.
The Performance and Microbiology of Ozone‐Enhanced Biological Filtration
Authors: Jr. James P. Malley , Eighmy T. Taylor , Collins M. Robin , Royce Jennifer A. , Morgan Daniel F.
Published: February 2018

Pilot‐scale studies were conducted to determine the effects of preozonation and water column biofilm support media on slow sand filtration. The performance of the enhanced slow sand filters was compared with that of the full‐scale treatment facility at Andover, Mass., which uses preozonation and granular activated carbon to enhance its conventional processes. Preozonation and biofilm support were observed to have a positive influence on filter performance, transformation of natural organic matter, microbiology, and removal of biodegradable dissolved organic carbon (BDOC). The pilot filter with the media of a larger effective size, an ozone dose of 2 mg per mg of nonpurgeable dissolved organic carbon (NPDOC), and biofilm support produced removals of turbidity, NPDOC, UV absorbance, and trihalomethane formation potential comparable to the full‐scale facility. And the enhanced pilot filter produced a lower finished‐water BDOC value than the full‐scale plant. Thus, enhanced slow sand filters hold promise for utilities that must comply with the Surface Water Treatment Rule and future disinfection by‐product rules.
Predicting and Verifying TOC Removal by PAC in Pilot‐Scale UF Systems
Authors: Adham Samer S. , Snoeyink Vernon L. , Clark Mark M. , Anselme Christophe
Published: February 2018

A modeling technique was developed to predict organics removal by powdered activated carbon (PAC) added as a pretreatment to hollow‐fiber ultrafiltration (UF). Model predictions were successfully verified for large‐ and small‐scale PAC‐UF pilot plants. Experiments were conducted using different water sources, PAC dosages, and backwashing frequencies. Natural organic matter in the water sources, represented by total organic carbon, was the target compound studied. The modeling procedure can be used in the design and evaluation of PAC‐UF systems.
Particle Removal and Head Loss Development in Biological Filters
Authors: Goldgrabe Julie C. , Summers R. Scott , Miltner Richard J.
Published: February 2018

The physical performance of granular media filters was studied under prechlorinated, backwash‐chlorinated, and nonchlorinated conditions. Overall, biological filtration produced a high‐quality water. Although effluent turbidities showed little difference between the performance of biological filters and conventional prechlorinated filters, differences were shown with particle counts. Although prechlorination yielded slightly better net particle removal than biological filtration, the overall order of magnitude and size range of particles removed was similar. Biological filtration also produced economical filter run times.
Overcoming the flood: how midwestern utilities managed disaster
Authors: Reid Joe
Published: February 2018

The value of detailed emergency plans became clear last summer to managers of drinking water utilities in Missouri, Illinois, and Iowa.

In 1993, massive flooding threatened midwestem drinking water treatment plants. In this article, the author reviews the experiences of four utilities—three of them subsidiaries of American Water Works Service Co. (AWWSC). AWWSC's Iowa‐American plant in Davenport was threatened, but it was never in immediate danger because it had recently built facilities above the 5000‐year floodplain. However, both Missouri‐American and Illinois‐American were stricken. Local workers in both places solved problems using equal parts of creativity and perseverance: in addition, AWWSC's New Jersey headquarters office supplied expert assistance. by telephone, computer, and an on‐site crisis team. A fourth plant, Des Moines Water Works, had no headquarters office to turn to, but its 235 employees efficiently staffed vital operational and engineering support teams. Meanwhile, General Manager L.D; McMullen spent 4 hours a day answering questions from the media. Officials at all four utilities noted the importance of planning and coordination to successful resolution of the crisis. In addition, they all stressed the value of communication among staff members and with the public.
Emergency preparedness and response
Authors: Shimoda Todd A.
Published: February 2018

Should an emergency strike, system safety and reliability can be increased if utilities have a plan of action.

Your utility probably runs like clockwork, the water moving smoothly from process to process before it flows through the distribution system. But would you still be able to operate reliably if a tornado struck or an earthquake hit or an outbreak of waterborne disease erupted? If you don't have an emergency preparedness plan in effect and disaster strikes, your utility will be scrambling to recover. And in hindsight, you will wish you'd had a plan at the ready. Following the step‐bystep process described here can increase the safety of your water supply, even in the event of an emergency.
Water industry best practices
Authors: Green Neville , Patrick Roger
Published: February 2018

The Sydney Water Board studied best practices around the world to see how its operations could be improved.

Studying the practices that make leading organizations efficient and at the same time able to provide high‐quality services can identify enormous potential for improvement. The Sydney Water Board (SWB) has embraced a program for change based on a study of “best practice” at a number of organizations worldwide. Key results of the study are presented here. The practices, systems, and technology that determine “best practice” were discovered with the cooperation of the organizations achieving a designated level of performance. In some cases, this involved organizations outside the water and wastewater industries. The changes that will be implemented at the SWB are far‐reaching, reducing costs in the areas studied by as much as 30 percent, while benefiting customer service and the environment.
Toxicological studies on MX, a disinfection by‐product
Authors: Daniel F. Bernard , Robinson Merrel , Olson Greg R. , Stober Judy A. , Page Norbert P.
Published: February 2018

Although its adverse effects on rats and mice are clear, MX requires further study before conclusions regarding its effect on humans can be made.

MX may be the most important single mutagen so far identified in chlorine‐disinfected waters. The objective of these studies was to determine the toxicity of MX to mammals by repeatedly administering varying dosages of the compound to B6C3F1 mice and Fischer rats. Toxicity was evidenced in rats by decreased food and water consumption—and decreased body weight gain at a high MX dosage. Similar weight loss was observed in male mice at MX dosages of 8, 16, and 64 mg/kg body weight. Based on these decreased body weight gains, the presence of stomach lesions, and other changes, 8 mg/kg was considered to be the lowest adverse effect level for oral exposure to MX for 14 days in mice and rats. Additional research is required to elucidate the effect of MX in drinking water on human health.
Exhausting and regenerating resin for uranium removal
Authors: Zhang Zhihe , Clifford Dennis A.
Published: February 2018

As expected, lowering the pH adversely affected uranium removal by anion resin—but at a lower than anticipated pH.

Uranium removal with chloride‐form anion exchange resin was studied near Houston, Texas, where an abandoned water supply well contained 120 μg/L uranium and 25 pCi/L radium. With this neutral‐pH, sulfate‐free water, the resin exhibited enormous capacity for the uranyl tricarbonate complex, still removing 95 percent uranium after nearly 16 months without regeneration and after 302,000 bed volumes of throughput. Computer predictions indicate, however, that the presence of sulfate in feedwater would significantly shorten the run length. The efficiency of uranium removal did not deteriorate at a feed pH as low as 5.6, but when the pH was lowered to 4.3, uranium removal decreased to 50 percent and the run length was shortened to 5,000 bed volumes. Results indicate that sodium chloride (NaCl) was an adequate regenerant and, within the range of 0.5 to 4.0 N, the more concentrated the NaCl, the more efficient it was.
Training for the next century
Authors: Rossiter David L.
Published: February 2018

Training isn't just for operators—and today it's likely to be brought to your TV screen by satellite.

This Roundtable discussion was moderated by David L. Rossiter, director of the technical and education department, AWWA, 6666 W. Quincy Ave., Denver, CO 80235. Other participants were John DeKam, director of AWWA's Michigan Section, outgoing chair of AWWA's Education Committee, and superintendent of the Bay Metropolitan Water Treatment Plant, 2691 N. Euclid Road, Bay City, MI 48706; Donna G. Jensen, water quality consultant, 197 Saddle Mountain Dr., Clancy, MT 59634, formerly field services program manager for the drinking water and subdivision section of the Water Quality Bureau, Montana Department of Health and Environmental Sciences; Ray Pirkl, director of distance learning programs, Portland Community College, 12000 S.W. 49th Ave., P.O. Box 19000, Portland, OR 97280‐0990, and a board member of the Portland Valley Water District; and Robert C. Renner, principal of Process Applications Inc., 2627 Redwing Road, Suite 340, Fort Collins. CO 80526. The discussion was held June 7, 1993, in San Antonio, Texas, and was updated by participants in March 1994.
SCADA trends and integration perspectives
Authors: Jentgen Lawrence A. , Wehmeyer Mark G.
Published: February 2018

The latest trends in SCADA system technology, a rapidly changing field, are being put into practice by the Navajo Tribal Utility Authority.

Supervisory control and data acquisition (SCADA) system technology—used by drinking water utilities to monitor and control remote facilities—has changed substantially in the past two to three years. This change has followed exponential advances in computer system performance, electronics, software, and standards. New SCADA systems, with their improved capacity for data management and communication with related systems, are a better bargain than previous SCADA systems. “Open systems,” in which all components can communicate regardless of brand name, are a common goal for manufacturers and users. Communication standards for utilities associated with open systems, utilities communication architecture, is described, as is the implementation of a SCADA system by the Navajo Tribal Utility Authority.
Synthetic adsorbent versus GAC for TCE removal
Authors: Hand David W. , Jr. Jon A. Herlevich , Perram David L. , Crittenden John C.
Published: February 2018

Results showed that the synthetic adsorbent studied is more efficient than GAC in removing trichloroethene from a groundwater—as well as being more resistant to fouling by natural organic matter.

The performance of a synthetic adsorbent in removing trichloroethene (TCE) from a groundwater containing natural organic matter (NOM) was compared with that of granular activated carbon (GAC). Adsorption equilibrium, kinetic, and pilot‐plant experiments were used to compare the adsorbents. Adsorption isotherm studies showed that the synthetic adsorbent had three to four times more TCE capacity than GAC over a TCE concentration range of 10‐2,000 μg/L. When preexposed for 24 weeks to a groundwater containing NOM, the synthetic adsorbent showed an average 12 percent loss in capacity compared with the single‐solute isotherm performed on the virgin adsorbent; GAC showed an average 35 percent loss in its virgin capacity for a preexposed time of only 10 weeks. Rapid small‐scale column tests and model calculations predicted pilot‐plant effluent profiles for the synthetic adsorbent. The pilot‐plant data confirmed that the synthetic adsorbent is more efficient than GAC in removing TCE.
Crafting a New Arsenic Rule
Authors: Pontius Frederick W.
Published: February 2018

Arsenic has long been known to be harmful to human health at high levels of exposure. The regulation of arsenic, however, presents several technical and policy challenges to the US Environmental Protection Agency (USEPA). The complexity of the issues involved has caused the agency to miss several deadlines during its efforts to prepare a primary drinking water regulation for arsenic, despite more than a decade of deliberations. The background, status, and issues involved in the development of this regulation are reviewed in this article.
Enhanced coagulation for arsenic removal
Authors: Cheng Robert C. , Liang Sun , Wang Hsiao‐Chiu , Beuhler Mark D.
Published: February 2018

Preliminary bench‐ and pilot‐scale investigations showed that coagulation is a promising treatment for removing arsenic from drinking water but that further work is needed, primarily on full‐scale plants.

The possible use of enhanced coagulation for arsenic removal was examined at the facilities of a California utility in 1992 and 1993. The tests were conducted at bench, pilot, and demonstration scales, with two source waters. Alum and ferric chloride, with cationic polymer, were investigated at various influent arsenic concentrations. The investigators concluded that for the source waters tested, enhanced coagulation could be effective for arsenic removal and that less ferric chloride than alum, on a weight basis, is needed to achieve the same removal.
Regulatory Compliance Costs
Authors: III John E. Cromwell
Published: February 2018

Understanding cost estimates is important to regulators as well as to utilities and their customers.

This roundtable discussion was moderated by John Cromwell, manager of special studies, Apogee Research Inc., 4350 East–West Highway, Bethesda, MD 20814. Other participants were: Janet L. Auerbach, chief, Regulation Management Branch, Drinking Water Standards Division, USEPA, 401 M St. SW, Washington, DC 20460; Jack DeMarco, superintendent of water quality and treatment, Cincinnati Water Works, 5651 Kellogg Ave., Cincinnati, OH 45228; Vanessa M. Leiby, executive director, Association of State Drinking Water Administrators, 1120 Connecticut Ave. NW, Suite 1060, Washington, DC 20036; Robert Raucher, vice‐president, RCG/Hagler Bailly, P.O. Drawer O, Boulder, CO 80306; and John S. Young Jr., vice‐president–engineering, American Water Works Service Co., 1025 Laurel Oak Rd., Voorhees, NJ 08043.
Protecting Consumers From Cryptosporidiosis
Authors: Miller Kenneth J.
Published: February 2018

The author answers the question: What can US drinking water suppliers do to protect consumers from cryptosporidium? He suggests the following as steps to take in protecting consumers: recognize that cryptosporidium oocysts are present in all surface water supplies; protect our watersheds; consider using ozone as a primary disinfectant; monitor raw water; optimize coagulant dosages; produce filtered water with low turbidity; evaluate and optimize filter media; evaluate backwash practices; advise people who may be at risk; and establish a policy making cryptosporidiosis a reportable disease.
NOM characterization and treatability
Authors: Owen Douglas M. , Amy Gary L. , Chowdhury Zaid K. , Paode Rajendra , McCoy George , Viscosil Kathy
Published: February 2018

These authors recommend that water treatment plant designers and operators use an integrated approach to optimize the collective effects of the treatment train for removing NOM.

Because it is not practical to analyze for each individual chemical compound present in natural organic matter (NOM), surrogate characterization methods were south that could identify interrelationships between NOM and its teratability. Source‐related and seasonal differences, effects of ozonation and coagulation on NOM, characterization of NOM in sequential unit processes including granular activated carbon, and aspects of bromide‐NOM interactions are explored. Whereas coagulants remove NOM intact, particularly higher‐molecular‐weight fractions, ozone converts humic to nonhumic material, resulting in NOM fractions that colud be difficult to remove by subsequent of separation techniques unles the bromide concentration is equalized in the individual fractions.
Take the Test: What Drives Your Utility's Monitoring Program?
Authors: Burlingame Gary A.
Published: February 2018

What motivates the people at your utility when it comes time to establish a water quality monitoring program? Does your utility simply do what is required under the SDWA, or does it assess whether the requirements are indeed adequate to document the quality of its drinking water? These and other questions are discussed in this Viewpoint.
SDWA Reauthorization: Progress or Politics
Authors: Pontius Frederick W.
Published: February 2018

The 104th session of Congress has only just begun, but the signs of change have been evident since last November's election. New members, new committee structure, and a new political order have set the stage for Congress to shape and consider legislative proposals thought inconceivable only a few years ago. Speculating on what might happen to the Safe Drinking Water Act (SDWA) is risky given the new political environment‐‐no one can say for sure what will happen.
Planning for the ICR
Authors: Owen Douglas M.
Published: February 2018

Utilities should begin final planning for the Information Collection Rule now.

The Information Collection Rule (ICR), developed as a part of the negotiated rule‐making (“reg neg”) package in 1993, will provide data to support further regulatory development for the proposed Disinfectants/Disinfection By‐products Rule and the Enhanced Surface Water Treatment Rule. Consequently, the development of valid, representative data is crucial to the success of future rule‐making processes. Considering the importance of the ICR effort, however, the time allowed for preparation is limited. Because of the complexity of the sampling and analytical programs, data entry requirements, and potential treatability studies, it is crucial that utilities begin final planning now. This article highlights important aspects of ICR requirements and makes specific recommendations to assist utilities in planning.
Enhanced coagulation: a preliminary evaluation
Authors: Cheng Robert C. , Krasner Stuart W. , Green James F. , Wattier Kevin L.
Published: February 2018

Enhanced coagulation, proposed as a best available technology in Stage 1 of the Disinfectants/Disinfection By‐products (D/DBP) Rule, is capable of controlling DBPs at a large California utility but will add to the cost of treatment.

Researchers conducted preliminary enhanced coagulation tests at the Metropolitan Water District of Southern California's (MWDSC's) 5.5‐mgd demonstration plant from August to October 1992. California State Project water and Colorado River water were tested. The first goal was to determine whether this mode of operation is an effective strategy for controlling disinfection by‐products (DBPs) and DBP precursors at MWDSC facilities. If this strategy proved to be successful, the second objective was to estimate the additional operational costs of complying with the proposed Disinfectants/DBP Rule and to identify the coagulation conditions that minimize these costs. Although the results show that enhanced coagulation can meet the criteria being considered for the rule, this process will increase MWDSC's cost of treatment.
Low‐pressure membranes: assessing integrity
Authors: Adham Samer S. , Jacangelo Joseph G. , Laîné Jean‐Michel
Published: February 2018

Although low‐pressure membranes are effective for removing selected microorganisms from untreated water supplies, until now the monitoring of their integrity has been neglected.

Several methods for monitoring the integrity of low‐pressure membranes were identified and evaluated using pilot‐scale systems. These techniques included particle counting, particle monitoring, turbidity monitoring, bubble‐point testing, air‐pressure‐hold testing, and sonic sensing. Although it does not provide continuous integrity monitoring throughout the filtration cycle, the air‐pressure‐hold test was the most effective direct monitoring method. Of the techniques that provide continuous monitoring, particle counting was the most sensitive.