bluuebunny/crossref_metadata_2025 huggingface dataset:
PCBs in sealants in water distribution reservoirs
Authors: Sykes Richard G. , Coate Alex R.
Published: February 2018

Disposal of PCB‐laden caulking material turned into a headache for East Bay MUD.

In a routine response to taste and odor complaints, the East Bay Municipal Utility District (EBMUD) drained and cleaned a 65‐mil‐gal reinforced‐concrete reservoir used to store treated water. The polysulfide caulking material used to seal joints between floor panels was in poor condition and required replacement. The deteriorated caulking was analyzed to determine whether it would require special handling before disposal. Analyses indicated that the caulking contained about 20 percent polychlorinated biphenyls (PCBs). Tests confirmed that the caulk did not pose a threat to drinking water quality; however, it was inappropriately released to a nearby drainage course, thus contaminating soils. EBMUD is completing a $2‐million remediation and restoration of the drainage course and is investigating PCBs in sealants in all its distribution system reservoirs. Unless disposed of properly, the PCB‐laden sealants pose a tremendous liability for EBMUD and for other water utilities with similar facilities.
Reducing bad‐debt expenses
Authors: Hamberg Gilbert L.
Published: February 2018

Utilities should terminate bankrupt nonresidential customers and seek payment rather than tolerating nonpayment as an allowed operating expense.

Water utilities should implement aggressive credit and collection strategies to minimize bad‐debt expenses from nonresidential customers. Before customers file for bankruptcy, utilities should have favorable laws and tariff provisions in effect and should implement such provisions for each customer. When customers file for bankruptcy, utilities should intervene and protect their pre‐ and postpetition interests. In a competitive economic climate, such a policy would make sense for utilities.
Technical note: constructing algae counting chambers
Authors: Rashash Diana M.C. , Parker Bruce C.
Published: February 2018

It is possible to easily and inexpensively construct plastic Palmer–Maloney chambers on site.

As shown in the preceding article, occasions arise when it is advantageous to use the Palmer–Maloney (P–M) method for algal enumeration. This method is not frequently used in the United States, possibly because a commercial source for the P–M chambers is difficult to locate. The possibility of constructing plastic P–M chambers on site was explored.
Implications of Unfunded Mandate Reform
Authors: Pontius Frederick W.
Published: February 2018

The Unfunded Mandates Reform Act (UMRA) of 1995 was signed into law March 22, 1995. The subject of contentious debate in Congress, this new law is expected to have sweeping consequences on the federal legislative and regulatory process. Implications of the UMRA are reviewed in this article.
Mutual aid and emergency response for water utilities
Authors: Riordan Raymond A.
Published: February 2018

California's award‐winning II WARN program lays the groundwork for mutual aid to water utilities during emergencies.

Some emergencies are more manageable than others, and most utilities can react effectively if an emergency or malfunction is localized. However, when calamity strikes—e.g., the Northridge, Calif., earthquake in January 1994 or Northern California's flooding in the winter of 1995—normal resources are not enough. To manage such situations, California water utilities have formed the Water Agency Response Network (WARN) to provide mutual aid during crises. In this article, the author describes the history and current operation of mutual‐aid efforts in California and recounts how the East Bay Municipal Utility District helped in the aftermath of the Northridge earthquake.
Record floods sweep through Georgia
Authors: Reid Joe
Published: February 2018

Last summer's flooding in Georgia mirrored the 1993 deluge in the Midwest, except that it hit in only three days.

Last summer, massive flooding once again challenged the ingenuity of drinking water system managers, this time with flash flooding that swept through Georgia and cut off water to more than 300,000 people. Hardest hit was Macon, where 150,000 people were without potable water for three weeks. In small rural communities such as Newton (population 750), the flood's effects stretched on for months. Newton did not fully recover
Time‐averaging water quality assessment
Authors: Reddy L.S. , Ormsbee Lindell E. , Wood Don J.
Published: February 2018

A time‐averaging model is a fast, efficient way to continuously assess water quality in the distribution system.

While reauthorization of the Safe Drinking Water Act is pending, many water utilities are preparing to monitor and regulate levels of distribution system constituents that affect water quality. Most f requently, utilities are concerned about average concentrations rather than about tracing a particular constituent's path. Mathematical and computer models, which provide a quick estimate of average concentrations, could play an important role in this effort. Most water quality models deal primarily with isolated events, such as tracing a particular constituent through adistribution system. This article proposes a simple, time‐averaging model that obtains average, maximum, and minimum constituent concentrations and ages throughout the network. It also computes percentage flow contribution and percentage constituent concentration. The model is illustrated using two water distribution systems, and results are compared with those obtained using a dynamic water quality model. Both models p redict average water quality parameters with no significant deviations; the time‐averaging approach is a simple and efficientalternative to the dynamic model.
The ICR: A Bumpy Road to Promulgation
Authors: Pontius Frederick W.
Published: February 2018

Promulgation of the Information Collection Rule (ICR) is significantly behind schedule. Although many water utilities have been preparing to comply with the ICR, technical and developmental issues have extended its final development. Some of the key issues that have yet to be fully resolved are reviewed here, such as: which systems will monitor; data flow; microbial methods; implementation and enforcement; unfunded mandates; and scheduling.
Bench and pilot testing under the ICR
Authors: Krasner Stuart W. , Westrick James J. , Regli Stig
Published: February 2018

Larger systems with high TOC concentrations are likely to be required by the ICR to conduct bench or pilot studies of granular activated carbon or membranes for the control of DBP precursors.

The Information Collection Rule (ICR) will require surface water systems serving ≥100,000 people with raw‐water total organic carbon (TOC) levels of >4.0 mg/L and groundwater systems serving ≥50,000 people with finished‐water TOC levels of >2.0 mg/L to conduct bench or pilot studies of granular activated carbon or membranes for the control of disinfection by‐product (DBP) precursors. The US Environmental Protection Agency has developed and is considering an approach to ensure that adequate data are obtained and that the resources for performing these studies are appropriately distributed. Also, the AWWA Disinfectants/DBP Technical Advisory Workgroup has developed a database on the geographic and temporal distribution of TOC in the United States.
Technical Note: Interference of Br−, BrO3−, and ClO3− with DOX determination
Authors: Symons James M.
Published: February 2018

Although no interference from bromate or chlorate was detected, a small positive interference of about 12 μg Cl−/L per 1 mg/L bromide was found in the presence of background organic matter.

In the dissolved organic halogen (DOX) analytic test, prior to combustion, the granular activated carbon (GAC) on which the DOX is adsorbed is washed with a sodium nitrate solution designed to remove any inorganic chloride that may have also adsorbed to the GAC. Thus, a potential positive interference is removed. This study investigated the effectiveness of the nitrate wash in eliminating possible interferences from bromide, bromate, and chlorate ions. No interference was detected from bromate or chlorate ion, but a small positive interference of about 12 μg Cl−/L per mg/L of bromide ion was found in the presence of background organic matter.
Evaluating a high‐efficiency ozone injection contactor
Authors: Schulz Christopher R. , Schafran Gary C. , Garrett L. Bernard , Hawkins Randall A.
Published: February 2018

With sidestream venturi injection and a specially designed downflow tube, this recently developed ozone contactor is an attractive alternative to the fine‐bubble diffusion contactor for high ozone concentrations.

A new type of ozone contactor, called the SVI‐DT (sidestream venturi injection with downflow tube) contactor, was evaluated at pilot scale and compared with the performance of a traditional countercurrent flow, fine‐bubble diffusion contactor. The specially designed downflow tube, equipped with one or more pressurized sidestream venturi injectors and installed inside an ozone reactor, facilitated the dissolution of ozone into water. The results showed that the SVI‐DT contactor achieved high mass transfer rates and outperformed the fine‐bubble diffusion contactor in removing color and yielding higher and longer‐lasting dissolved ozone residuals. The hydraulic behavior of the new contactor was also evaluated, and operating limits were established for maintaining stable two‐phase flow conditions in the downflow tube.
Reducing fluoride by managed POU treatment
Authors: Jr. Benjamin W. Lykins , Astle Robert , Schlafer John L. , Shanaghan Peter E.
Published: February 2018

Reducing fluoride at the point of use may be a solution for some small systems.

Through the cooperative efforts of regulatory agencies, utility management, and equipment manufacturers, a small systems demonstration study involving reverse osmosis point‐of‐use (POU) drinking water units for fluoride reduction has been successfully concluded in Suffolk, Va. This three‐year study offers evidence for the regulatory consideration of individual POU treatment units for fluoride reduction in small public water systems if more conventional measures are unavailable.
An advanced oxidation process for DBP control
Authors: Symons James M. , Worley Kevin L.
Published: February 2018

Potentially of use to small systems for disinfection by‐products control, a relatively simple advanced oxidation process was evaluated at bench scale.

Small water utilities often have difficulty operating complicated treatment processes. The advanced oxidation process investigated here is simple, involving only a pump to add hydrogen peroxide and a power supply for the ultraviolet lamps, and the process does not produce any solid residuals. The results of these studies show that a photon‐flux‐driven pseudo‐first‐order model (known as the Prengle–Shimoda rate model) could be used to predict the destruction of total organic carbon, dissolved organic halogen, and dissolved organic halogen precursors.
Correlating Cryptosporidium and Giardia with microbial indicators
Authors: Chauret Christian , Armstrong Neil , Fisher Jason , Sharma Ranu , Springthorpe Susan , Sattar Syed
Published: February 2018

As in other areas of North America, Cryptosporidium oocysts and Giardia cysts were ubiquitous in surface waters of the Ottawa, Canada, region, although the rivers studied are considered relatively pristine.

Concentrations of Cryptosporidium oocysts, Giardia cysts, fecal and total coliforms, fecal streptococci, Aeromonas sp., Pseudomonas aeruginosa, Clostridium perfringens, algae, and coliphages were measured in each of 51 raw water samples from rivers in the Ottawa (Canada) region over three months. This study also examined correlations between the protozoa concentrations and current or potential indicators of water quality in raw surface water. The article also reports the concentrations of Cryptosporidium oocysts and Giardia lamblia cysts in two water treatment plants and in one wastewater plant. Significant correlations between fecal streptococci and Cryptosporidium oocysts and between Giardia and both somatic coliphages and algae were observed in raw surface water samples, but the relationships appear to be watershed‐dependent. No significant correlation was obtained between the presence of the protozoa and that of Clostridium perfringens or any of the other indicators.
Improved monitoring of corrosion processes
Authors: Porter Russell L. , Ferguson John F.
Published: February 2018

This improved monitoring protocol, with its simple experimental design and four methods of analysis, allows for a more complete picture of corrosion processes and inferences about scale buildup.

The effect of orthophosphate addition (1 mg/L as P) on copper and lead–tin solder corrosion was monitored using an experimental coupon exposure apparatus with measurement by standing water metals analysis, gravimetric analysis, direct galvanic current metering, and potentiodynamic scan analysis. Orthophosphate addition appeared to have a significant effect on lead–tin solder corrosion although the results of each analysis differed in magnitude. The effect of orthophosphate addition on copper corrosion was less clear with gravimetric analysis showing a significant effect, whereas metals release analysis showed only a slight effect.
TOC removal in biological filters
Authors: Hozalski Raymond M. , Goel Sudha , Bouwer Edward J.
Published: February 2018

Optimizing the coagulant dosage offers the most effective means of maximizing TOC removal; biofiltration may be used to augment removals.

Laboratory‐scale biologically active sand filters were used to evaluate the effect of natural organic matter (NOM) source and empty bed contact time (EBCT) on the removal of total organic carbon (TOC) from coagulated and ozonated NOM solutions. Ozonation at dosages in the range of 2.0 to 4.0 mg ozone/mg TOC were used to enhance biodegradation of the organic matter. TOC removal in the biofilters ranged from 16 to 33 percent of the biofilter influent concentration. TOC removal was significantly affected by the source of the organic carbon but was independent of EBCT in the range of 4 to 20 min. In the context of an entire water treatment plan, including coagulation and biofiltration, the contribution of biofiltration to TOC removal was relatively small compared with total removals across the entire treatment train. In one biofiltration experiment, however, removal of the biodegradable fraction of TOC was 100 percent, suggesting that biofilters may be effective in reducing subsequent regrowth in distribution systems.
Promoting Efficient Water Use
Authors: Anderson‐Rodriguez Lynn
Published: February 2018

A disturbing trend threatens to return the role of water conservation to that of bygone days, when it was regarded merely as a means to cope with temporary water shortages such as droughts. Water utilities across the United States, and particularly in California, are facing pressures to sell more water to increase revenues. The author voices concerns about developing solutions to address challenges to water conservation programs and maintain support in the water supply community.
Implementing the US Energy Policy Act
Authors: Vickers Amy
Published: February 2018

Since the US Energy Policy Act went into effect two years ago, a new generation of water‐efficient plumbing fixtures has been installed in homes, businesses and institutions. This process will continue through about 2025, by which time all existing high‐volume fixtures will have been replaced. Passage of this act has raised interesting issues that have technical, financial, and policy implications for water utilities‐‐particularly those with conservation programs. This article reviews some of these effects.
What Are the Options for Reuse?
Authors: Crook James
Published: February 2018

Nonpotable uses of reclaimed water are well established, but indirect potable reuse is not as widely accepted.

This Roundtable about water reuse was conducted June 20, 1995, in Anaheim, Calif. Discussion leader was James Crook, director of water reuse, Black & Veatch, 100 Cambridge Park Dr., Cambridge, MA 02140. Other participants were Robert C. Cooper, vice‐president, Bio‐Vir Laboratories, Stone Road, Benicia, CA 94557 and professor emeritus, University of California School of Public Health; Robert Hultquist, senior sanitary engineer with the California Department of Health Services, 2151 Berkeley Way, Berkeley, CA 94704; James J. Morgan, Goldberger Professor of Environmental Engineering Science, California Institute of Technology, Caltech 138‐78, Pasadena, CA 91125; Daniel A. Okun, Kenan Professor of Environmental Engineering, Emeritus, University of North Carolina, CB 8060, Chapel Hill, NC 27599; Thomas G. Richardson, principal engineer, Montgomery Watson, 750 B St., Suite 1610, San Diego, CA 92101; and Ronald Young, general manager of the Irvine Ranch Water District, 15600 Sand Canyon Ave., Irvine, CA 92718.
Revenue instability induced by conservation rates
Authors: Chesnutt Thomas W. , McSpadden Casey , Christianson John
Published: February 2018

When a utility's costs change quickly, rates can be designed to correctly hedge against revenue uncertainty

The shift toward conservation rate structures, although they may provide better incentives to use scarce water wisely, changes who pays what and can increase the variability of future revenue streams to the water agency. Though the definition of the “correct” rate structure varies by community, the managerial strategies necessary to cope with the uncertainty brought about by conservation rate structures apply universally. Revenue instability directly increases water suppliers' borrowing costs and adds indirect costs in the form of more complicated planning to provide for a reliable future water supply. This article describes an empirical study using data from two water agencies that have adopted conservation rate structures. The article proposes ways quantitative tools may be used to (1) measure and cope with added uncertainty and (2) make explicit the magnitude of trade‐offs between revenue stability, equity, and the provision of incentives for efficient use of water resources.
Conservation feebates
Authors: Collinge Robert A.
Published: February 2018

A combination of fees and rebates—“feebates”—offers the economic efficiency of marginal cost pricing but keeps revenues equal to costs.

Municipal water rates are expected to satisfy three objectives: efficiency, revenue neutrality to the utility, and distributional equity. Unfortunately, adjusting rates to efficiently achieve use and conservation targets would ordinarily generate excessive revenues. Rather than mold one tool to the service of three masters, this article suggests combining three separate tools. The first sets the water rate to cover the utility's costs. The second assigns customers allotments to water use. The third either charges a fee for use that exceeds the customer's allotment or hands out rebates for consumption below that allotment. The fees pay for the rebates—thus the term “feebate.” The outcome is (1) revenues to the utility just sufficient to cover costs, (2) efficient water consumption by municipal water customers without conservation mandates, and (3) revenue effects that can be spread fairly across various categories of customers.
Navigating cyberspace: a roadmap to the Internet
Authors: Berberich Charles W.
Published: February 2018

The World Wide Web offers water professional easy‐to‐use access to information, contacts, and interaction.

The Internet is no longer just a specialized tool for academic research, and gaining access to it has been simplified by on‐line service providers. These services offer special‐interest discussion groups and large collections of data to their members. Increasingly, being on the Internet means easy access to the World Wide Web, through which users can gain access to material from computers worldwide. AWWA has a presence on the Internet, as do other professional associations, state and federal government agencies, universities, manufacturers of supplies for the water industry, environmental groups, publications, and consulting firms. A five‐page directory of web site addresses for these information sources is included in this article.
Siting monofills for residuals using GIS
Authors: Karthikeyan K.G. , Elliott Herschel A. , Brandt Robin C.
Published: February 2018

GIS modeling is a useful screening tool for water utilities that plan to establish monofills.

A geographic information system model was developed to locate monofill construction sites for drinking water treatment residuals. Suitability was defined primarily by a site's capacity to prevent leaching of constituents of the residual to groundwater. The model considered land use, topography, bedrock geology, soils, and state regulatory criteria. Adsorption experiments were conducted using cadmium as a representative pollutant to assess the ability of the soils to limit treatment residual migration. Applied in southeastern Pennsylvania, the methodology identified only 6.37 sq mi (16.5 km2), 2.1 percent of the area screened, as suitable for monofills. The major strength of this model is the quick elimination of parcels that fail to meet regulatory or groundwater protection standards. Because it identifies sites that afford the greatest environmental protection, the model is also a valuable aid in winning public acceptance of
The SDWA and Small Systems: What's on Tap?
Authors: Miller Ellen G.
Published: February 2018

The Safe Drinking Water Act (SDWA) has not yet been reauthorized, but some recent developments are encouraging. The Senate unanimously passed S. 1316, a bill that would reauthorize the SDWA. The bill includes changes to the standard‐setting process, establishment of state‐run loan programs, and return of discretionary authority to the states. That the bill was passed by a vote of 99‐0 in the Senate despite environmental lobbying groups spending a lot of money to defeat it, is a strong statement regarding a widely held belief in the need for such changes. In light of these anticipated changes, Ellen Miller asked three small system experts‐‐Tom Duck, Neil Groshong, and John Sadziwicz‐‐what small systems can do now to begin preparing for the reauthorized SDWA.
Inside S. 1316
Authors: Pontius Frederick W. , Warburton Albert E.
Published: February 2018

On November 29, 1995, the Senate passed S. 1316, the Safe Drinking Water Act (SDWA) amendments, by a vote of 99 to 0. Details of the development of S. 1316, the Library of Congress' Congressional Research Service digest, a section‐by‐section summary, and the full text of the bill are available. Only the major provisions of the bill are summarized here: state revolving fund established; standard‐setting process revised; DBPs, radon, arsenic and sulfate addressed; filtration and disinfection addressed; monitoring to be revised; small system variances modified; capacity development addressed; source water quality partnerships; research programs authorized; authorizations provided for program grants; federal agency compliance; and watershed demonstration project.
Inside the Federal Budget Processes
Authors: Pontius Frederick W.
Published: February 2018

Disputes over the federal budget are an annual event for members of Congress, federal agencies, and the President. This year, however, ideological disagreements have been especially sharp. Six months into fiscal year 1996, two government shutdowns have occurred, and the US Environmental Protection Agency (USEPA) is still operating under a temporary budget. The federal budget picture is so complicated that even few members of Congress understand it. This article takes a brief look inside the federal budget process, the forces driving it, and the implications it has for drinking water suppliers.
Sydney Water's public–private partnership
Authors: Alla Pierre M.J. , Manzi David
Published: February 2018

A build–own–operate contract between Australian Water Services and Sydney Water Corporation demonstrates the advantages of such arrangements.

The Prospect Water Filtration Plant will be one of the largest water treatment plants in the world, with an initial capacity of 780 mgd (3,000 ML/d) and a potential future capacity of 1,090 mgd (4,200 ML/d). It has been developed under a build–own–operate (BOO) contract between Australian Water Services (the private operator) and the Sydney Water Corporation (the public authority). This project showcases the advantages of BOO contractual arrangements. The article describes the implementation of the project through competitive bidding, elaborates on the partnership approach, and outlines the main features of the contractual arrangement. Perspectives of both the
Arsenic removal by ferric chloride
Authors: Hering Janet G. , Chen Pen‐Yuan , Wilkie Jennifer A. , Elimelech Menachem , Liang Sun
Published: February 2018

Source water composition affects removal efficiency.

Bench‐scale studies were conducted in model freshwater systems to investigate how various parameters affected arsenic removal during coagulation with ferric chloride and arsenic adsorption onto preformed hydrous ferric oxide. Parameters included arsenic oxidation state and initial concentration, coagulant dosage or adsorbent concentration, pH, and the presence of co‐occurring inorganic solutes. Comparison of coagulation and adsorption experiments and of experimental results with predictions based on surface complexation modeling demonstrated that adsorption is an important (though not the sole) mechanism governing arsenic removal during coagulation. Under comparable conditions, better removal was observed with arsenic(V) [As(V)] than with arsenic(III) [As(III)] in both coagulation and adsorption experiments. Below neutral pH values, As(III) removal–adsorption was significantly decreased in the presence of sulfate, whereas only a slight decrease in As(V) removal–adsorption was observed. At high pH, removal–adsorption of As(V) was increased in the presence of calcium. Removal of As(V) during coagulation with ferric chloride is both more efficient and less sensitive than that of As(III) to variations in source water composition.
Cost of membrane softening in Florida
Authors: Bergman Robert A.
Published: February 2018

Membrane treatment cost data based on actual plant operations provide an easy way to estimate order‐of‐magnitude costs for membrane systems.

Costs for membrane softening plants in Florida with capacities from 1 to 14 mgd (3.8 to 53 ML/d) are presented. Costs for installed membrane system, water treatment plant construction, operation and maintenance, and total treated water production are included based on data from the author's survey of operating membrane softening plants. Unit cost curves are included as a function of installed membrane permeate capacity. The effects of membrane bypass and blending, plant operating factors, concentrate disposal, and amortization at various interest rates are discussed.
Implementing the Information Collection Rule
Authors: Pontius Frederick W.
Published: February 2018

The final Information Collection Rule (ICR) was signed May 1, 1996, by US Environmental Protection Agency (USEPA) Administrator Carol Browner and published in the Federal Register May 14. Generally, the ICR applies to surface water systems serving 100,000 people or more and to groundwater systems serving 50,000 people or more. Detailed applicability criteria included in the final rule determine which requirements will apply to which systems. Implementation of this rule is now beginning under a schedule developed by USEPA and reviewed in this article. Also discussed is AWWA's ICR Assistance Team, or A‐Team, which provides help to water utilities and consultants regarding compliance with the ICR.
An introduction to epidemiology
Authors: Craun Gunther F. , Calderon Rebecca L. , Frost Floyd J.
Published: February 2018

Epidemiology is a complex and subtle science that is being applied increasingly to disease outbreaks caused by drinking water contaminants.

Epidemiologists study the occurrence and causes of disease in human populations and apply this knowledge to the prevention and control of health problems. Studies are increasingly being conducted to determine health risks that may be associated with environmental exposures, especially from drinking water. This article will help drinking water professionals become more familiar with the terminology, types of studies that can be conducted, sources of possible bias, and some of the reasons why results can be controversial.
US outbreaks of cryptosporidiosis
Authors: Solo‐Gabriele Helena , Neumeister Shondra
Published: February 2018

An overview of US cryptosporidiosis outbreaks suggests that conventional treatment processes operated at minimum regulatory compliance levels are ineffective at preventing transmission of the disease.

Drinking water has been implicated as the mode of transmission in several outbreaks of cryptosporidiosis throughout the United States. This review of US outbreaks describes characteristics of the raw water supply, suspected sources of contamination, water treatment methods, and corrective actions. Of the total number of outbreaks, roughly half were associated with groundwater sources; the majority of affected individuals, however, were served by drinking water drawn from surface water. Wastewater was implicated as the source of contamination of raw or treated water for roughly half of the outbreaks. Nonpoint sources, such as agricultural runoff, were suspected sources of contamination in the remaining outbreaks. The majority of affected individuals were served by treatment plants using coagulant addition, filtration, and chlorine disinfection processes. Although treatment deficiencies and suboptimal operational practices were noted during some of the outbreaks, all treatment plants were complying with federal and local regulations. Existing regulations and water supply systems, especially those utilizing surface water sources, should be reevaluated.
Environmental methods for Cryptosporidium
Authors: Jakubowski Walter , Boutros Susan , Faber Walter , Fayer Ron , Ghiorse William , LeChevallier Mark , Rose Joan , Schaub Stephen , Singh Ajaib , Stewart Mic
Published: February 2018

A number of approaches offer promise for addressing the limitations of current antibody‐based detection methods.

This report was prepared by the Working Group on Waterborne Cryptosporidiosis (Technical Task Force E, Developmental Status of Environmental Sampling, Water Testing, and Surrogate Indicators). Methods for detecting Cryptosporidium oocysts in water have centered around microscopic examination of fluorescent antibody‐stained concentrates from large‐volume water samples. The limitations of these antibody‐based methods include the need for experienced analysts, lengthy analytical time, expense, lack of specificity, erratic efficiency, low precision, and difficulty in determining viability. A number of methods, assays, and procedures that have the potential for ameliorating some of these limitations are currently being evaluated. How successful such processes will be remains to be demonstrated by the scientific community.
Improving Small Systems for Fire Protection
Authors: Hoffman Gary L.
Published: February 2018

Safe drinking water, rather than fire protection, is usually the impetus for improvements to water systems. Although smaller systems do not have massive, high‐powered delivery systems, many rural and suburban communities are nevertheless concerned about improving their water transmission capacities to provide or enhance fire‐fighting capacities. This paper discusses the benefits of improved fire‐fighting capacity and describes the improvements one small community has made to increase water pressure and improve transmission in its water system. The experiences of another small community in developing guidelines that address fire flow capabilities are also discussed.
Bromate ion removal by HEEB irradiation
Authors: Siddiqui Mohamed S. , Amy Gary L. , Cooper William J. , Kurucz Charles N. , Waite Thomas D. , Nickelsen Michael G.
Published: February 2018

High‐energy electron‐beam irradiation removes bromate after its formation, when other control strategies are not as effective.

Proposed drinking water regulations will specify a maximum contaminant level of 0.01 mg/L for bromate ion (BrO3−). This study used high‐energy electron‐beam irradiation to remove BrO3− after formation, when other control strategies are not as effective. BrO3− was reduced to bromide ion (Br−), with bromine (HOBr/OBr−) as intermediate. A dose of 60 krads was sufficient to reduce 70 percent of BrO3− from an initial concentration of 100 μg/L. The presence of electron scavengers such as hydrogen peroxide and nitrate significantly reduced BrO3− removal, whereas the addition of the OH radical scavenger such as t‐butanol did not affect the removal of BrO3−. This indicates that aqueous electrons (eaq−) are mainly responsible for BrO3− destruction. The presence of natural organic matter decreased BrO3− reduction efficiency. The reaction of eaq− with various bromine species in water was used to model and simulate experimental data for the destruction of BrO3−. Computer model predictions were in fairly good agreement with the experimental results.
Illinois Community Examines Aquifer Protection Measures
Authors: Cobb Richard P. , Dulka Anthony
Published: February 2018

Marengo, a community in northern Illinois with a population of 4,768, is developing a comprehensive management program to protect the city's groundwater resources. The city has established a groundwater protection team to evaluate various site‐specific programs for managing and protecting the community's five‐year recharge area. This paper discusses the various aspects of Marengo's groundwater protection program including a voluntary pollution prevention program for area businesses.
Source Water Protection Under the Amended SDWA
Authors: Pontius Frederick W.
Published: February 2018

The Safe Drinking Water Act (SDWA) amendments of 1996 contain several important provisions intended to better protect source water from contamination. Three new programs are created, and the existing programs administered by the US Environmental Protection Agency (USEPA) related to source water protection are reauthorized. The amended SDWA provisions are summarized.
Iron oxide adsorption and UF to remove NOM and control fouling
Authors: Chang Yujung , Benjamin Mark M.
Published: February 2018

Addition of iron oxide particles to a UF system can significantly increase NOM removal efficiency, slowing membrane fouling.

This study applied a novel single‐fiber membrane module to study fouling of ultrafiltration (UF) membranes by natural organic matter (NOM) molecules, and used a combined iron oxide–UF process to reduce that fouling. Addition of iron oxide particles to a UF system can significantly increase NOM removal efficiency, because NOM molecules that would otherwise pass through the membrane sorb to the oxides and are retained. Furthermore, despite the fact that iron oxide particles cannot selectively adsorb foulant molecules, their presence in the system can reduce the membrane fouling dramatically. This effect is mediated through two processes: a decrease in the NOM concentration in the circulation loop because of sorption and the formation of iron oxide cake layer deposits on the membrane surface. In such a system, the condensed layer of NOM forms on top of the cake, protecting the underlying membrane surface.
Business planning for small system capacity development
Authors: Cromwell John E. , Rubin Scott J. , Marrocco Frederick A. , Leevan Mark E.
Published: February 2018

Business planning will help small systems harness the power of local informed self‐interest, identify communities that need extra help, and support state and local government efforts to enhance incentives and remove barriers to possible improvements.

Pennsylvania began developing a statewide strategy to address viability of small water systems in 1990. The authors have been continuously involved in this process. Many pieces of the program are in place and provide a foundation for meeting capacity development and affordability provisions of the 1996 Safe Drinking Water Act amendments.
Improving service to small communities
Authors: MacDonald Jacqueline A. , Zander Amy K. , Snoeyink Vernon L.
Published: February 2018

The National Research Council suggests a strategy that dovetails with three key provisions of the 1996 SDWA amendments.

The National Research Council recently published a report calling for a three‐part strategy to improve the quality of water service in small communities. The strategy, outlined in this article, involves improving the sustainability of financing and management of small water systems, enhancing the training of small system operators, and reducing duplication of costly pilot testing efforts for small system technologies. These steps correlate to key provisions of the 1996 Safe Drinking Water Act amendments and should assist the US Environmental Protection Agency, states, and water utilities with implementing those amendments.
Predicting As removal during metal hydroxide precipitation
Authors: McNeill Laurie S. , Edwards Marc
Published: February 2018

Data from two utility surveys led to the development of a simple model for predicting arsenate removal at full‐scale alum coagulation, ferric coagulation, and iron–manganese removal plants.

A simplified isotherm is described that can predict the extent of arsenate removal at drinking water utilities practicing coagulation or iron–manganese (Fe–Mn) removal. If all possible sources of particulate iron and aluminum hydroxide present in the system are accounted for, the model predicts arsenic (As) removal to within ±13 percent (90 percent confidence) for Fe coagulation at pH 6.5–8 and alum coagulation at pH < 7.6. Analysis of full‐scale treatment data suggests that colloidal aluminum (Al) flocs with sorbed arsenate [As(V)] may pass through filters, thereby decreasing overall As removal efficiency. Thus, Al solubility and particle stability must be minimized to improve As removal. If stability and solubility of aluminum hydroxide flocs are not a problem, alum and Fe coagulants have nearly equal capacity for sorbing As(V). Survey results also demonstrate the importance of particulate As.
Ozonation and BDOC removal: effect on water quality
Authors: Cipparone Lori A. , Diehl Alicia C. , Speitel Gerald E.
Published: February 2018

Batch experiments indicate biological treatment improves overall water quality and reduces biological regrowth.

Batch experiments were conducted to determine the effect of several ozone dosages and biological treatment on a surface water. Total organic carbon (TOC) concentration, chlorine demand, bacterial regrowth, and disinfection by‐product (DBP) formation were measured after ozonation and after subsequent biodegradation. TOC removal increased with ozone dosage, but the extent of removal from biodegradation alone leveled out after an ozone dose of 1 mg O3/mg TOC. Chlorine demand reduction was highly correlated with the TOC removal, and chlorine residuals were maintained significantly longer in ozonated and biologically treated water, compared with water treated with ozone alone. Biological organic carbon removal delayed bacterial regrowth in chlorinated water, and DBP formation was reduced for ozone doses at or below 3 mg O3/mg TOC. Although higher chlorine residuals were maintained in the biologically treated water, higher DBP concentrations were not produced, indicating that biological treatment reduced DBP precursor levels.
Evaluation of optical detection methods for waterborne suspensions
Authors: Sethi Virendra , Patnaik Priyamvada , Biswas Pratim , Clark Robert M. , Rice Eugene W.
Published: February 2018

Making design criteria for turbidimeters more stringent would enable an integrated approach to turbidity measurement and particle detection.

Turbidimeters and optical particle counters (OPCs) are used to monitor particulate matter in water. The response from these instruments is governed by the optical properties of the suspension and the instrument design. The recommended design criteria for turbidimeters allow for large tolerances that lead to variations in measurements from different instruments. OPCs provide size‐specific information but may inaccurately size microorganisms or particles having optical properties different from those of the calibration particles. The authors evaluate the effects of optical design parameters in turbidimeters and OPCs. Performance data from two OPCs are presented. A multiple‐angle light‐scattering method was developed to obtain “optical signatures” from suspensions of monodisperse spheres and several microorganism isolates. Such “signatures” provide more optical information on waterborne particles and may also be used to identify specific types of microorganisms in real time.
State Revolving Loan Fund Guidance Issued
Authors: Pontius Frederick W.
Published: February 2018

The Safe Drinking Water Act (SDWA) amendments of 1996 created the first ever state revolving loan fund (SRLF) for drinking water infrastructure. The amendments authorize a total of $9.6 billion for fiscal year 1994 through fiscal year 2003. These funds will provide relief for many financially strapped systems in need of federal assistance to fund improvements in order to comply with SDWA and related regulations.
Predicting liquid bleach decomposition
Authors: Gordon Gilbert , Adam Luke C. , Bubnis Bernard P. , Kuo Ching , Cushing Robert S. , Sakaji Richard H.
Published: February 2018

A hypochlorite ion degradation model helps utilities using liquid bleach to develop control strategies to minimize formation of chlorate ion.

Studies have led to an understanding of how chlorate ion (ClO3–) formation in the pH 6–13 region from decomposing bleach is affected by pH, temperature, NaOCl concentration, chloride ion concentration (by means of an ionic strength effect), and transition metal ion impurities. The hypochlorite ion degradation model developed by Gordon and Adam predicts free available chlorine decomposition, ClO3– formation, and oxygen generation. Thus, a utility applying liquid bleach can use this newly developed model to predict the time‐dependent changes that occur in stored liquid bleach and to develop chemical specifications and control strategies to minimize the formation of ClO3– during the storage of sodium hypochlorite. The field studies reported here provide verification of the model showing a strong correlation between the model predictions and the measured data taken in the field.
Optimizing treatment through Fe and Mn fractionation
Authors: Carlson Kenneth H. , Knocke William R. , Gertig Kevin R.
Published: February 2018

Application of Fe and Mn fractionation procedures helps improve finished water at three treatment facilities.

A series of filtration steps was used to separate iron (Fe) and manganese (Mn) into soluble, colloidal, and particulate fractions. Two case studies demonstrate how fractionation data can improve understanding of the origins and removal of Fe and Mn. The Mn species present in one water source were shown to be regulated by a biogeochemical cycle in which the natural oxidation and reduction of Mn appeared to be microbially mediated. Mn removal was improved by adjusting the application of potassium permanganate to account for this cycle. A groundwater treatment plant was suffering from high postfilter Fe and Mn concentrations. Fractionation data identified the problem as inadequate solids capture, not oxidant dosage, allowing a quick solution. The unexpected oxidation of Mn with chlorine (Cl2) was attributed to Fe oxide surface catalysis. Without adequate particle removal (no coagulant added), applying Cl2 on top of the filters exhibited superior removal to adding Cl2 before a detention basin.
Bromate minimization during ozonation
Authors: Song Rengao , Westerhoff Paul , Minear Roger , Amy Gary
Published: February 2018

A study of BrO3‐ and TOBr production during ozonation indicates that both can be controlled by decreasing HO· and HOBr/OBr‐ concentrations.

Significant levels of both bromate (BrO3‐) and brominated organics, measured as total organic bromine (TOBr), form during ozonation of water containing bromide and natural organic matter (NOM). Ozonation of several ultrafiltration and reverse osmosis membrane NOM isolates leads to approximately 17 percent of the bromide converting to bromate and 7 percent to TOBr. Depressing pH or adding hydroxyl radical scavengers decreases BrO3‐ production but promotes TOBr formation. In the presence of NOM, hydrogen peroxide addition lowers TOBr formation and may increase or decrease BrO3‐ formation, depending on other water quality factors. Ammonia addition decreases both BrO3‐ and TOBr production. Both BrO3‐production and TOBr production decrease when the initial bromide concentration is decreased and the ratio of ozone dosage to dissolved organic carbon is lowered.
Technical note: Does hydroxyl radical oxidize bromide to bromate?
Authors: Symons James M. , Zheng Michael C.H.
Published: February 2018

Exposing bromide ion–laden water to hydrogen peroxide and H2O2–UV‐Vis irradiation did not result in the formation of bromate ion.

Although ozonation of bromide ion–containing water can produce bromate ion, studies with the hydrogen peroxide–ultraviolet‐visible irradiation (H2O2–UV‐Vis) advanced oxidation process demonstrated that this reaction did not occur when this advanced oxidation process was used. Reduction of any HOBr formed by the excess H2O2 used in this process may have prevented bromate formation.
Carboxylic acids: formation and removal in full‐scale plants
Authors: Gagnon Graham A. , Booth Stephen D.J. , Peldszus Sigrid , Mutti Dennis , Smith Franklyn , Huck Peter M.
Published: February 2018

Carboxylic acids were formed upon ozonation but were not completely removed by biological filtration, which could have implications for bacterial regrowth in distribution systems.

This article presents data on the formation and removal of carboxylic acids in a full‐scale treatment plant employing ozonation and biological filtration. Carboxylic acid concentrations increased after ozonation and decreased through subsequent filtration. Simple linear relationships between major water quality parameters (e.g., temperature, pH) and acid formation did not exist. Yields of carboxylic acids on ozonation were an order of magnitude greater than for the corresponding aldehyde. An empirical linear model could describe the removal of carboxylic acids through biological filtration from a practical point of view. However, the data suggest the removal mechanism may be complex. Although contact times in the filters were quite long (on the order of 30 min), removal of several carboxylic acids was incomplete (e.g., average effluent concentration of formate was 44 μg/L).
Protozoa in open reservoirs
Authors: LeChevallier Mark W. , Norton William D. , Atherholt Thomas B.
Published: February 2018

Open finished water reservoirs are vulnerable to microbial contamination, but current analytical techniques do not permit assessment of the organisms' viability.

The impact of storage of potable water in open reservoirs was assessed by examining inlet and effluent water samples from six open finished water reservoirs used by four New Jersey utilities. Water quality parameters investigated included Giardia cysts, Cryptosporidium oocysts, total and fecal coliforms, bacteriophage, heterotrophic plate count bacteria, turbidity, particle counts, chlorine residuals and other parameters. Fifteen percent of inlet samples and 25 percent of effluent samples contained the organisms. When data for cysts and oocysts were combined, the difference in concentrations between the inlet and effluent was statistically significant, even when results were adjusted for analytical recovery efficiency. Although the concentration of protozoa increased following open reservoir storage, the analytical method used does not permit assessment of the organisms' public health significance. Nearly all of the cysts and oocysts were empty or contained undiscernible internal structures, suggesting the health risk is low. The implication of these findings for watershed control programs is discussed.