faculty dr. temesgen garoma formation of...

World Water Forum College Grant Program 2011-2013 Grant Proposals

College San Diego State University

Faculty Dr. Temesgen Garoma

Project #116

Formation of Halonitromethanes during Ozonation of Drinking Water

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A. Cover Page

A.1. Institution

College Department of Civil, Construction and Environmental Engineering San Diego State University

Address 5500 Campanile Drive City, State, Zip Code San Diego, CA 92182-1324 Website http://ccee.sdsu.edu, http://attila.sdsu.edu/~garoma/ Make Check Payable to San Diego State University Research Foundation

Attn: Eugene Stein, Co-Director, Sponsored Research Contracting and Compliance 5250 Campanile Drive San Diego, CA 92182-1931

A.2. Project Type

Application Strand Check One

Local Project Name Formation of Halonitromethanes during Ozonation of Drinking Water

Global Project Name

A.3. Student Project Manager

Student Project Manager Cintia Lau

Undergraduate or Graduate Undergraduate

Department Department of Civil, Construction and Environmental Engineering

Mobile Phone 619-737-8888

Email [email protected]

A.4. Faculty Project Manger

Faculty Project Manager Temesgen Garoma

Department Department of Civil, Construction and Environmental Engineering

School Address 5500 Campanile Drive, San Diego

CA 92182-1324

Telephone 619-594-0957

Email [email protected]

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B. Project Summary The proposed project will investigate the formation of halonitromethanes, an important class of disinfection byproducts, during ozonation and ozonation followed by chlorination of drinking water. Optimal conditions that will lead to the formation halonitromethanes during ozonation will be also identified so that such conditions can be avoided in engineering practices.

C. Contact Information The primary contact for this proposal is Dr. Temesgen Garoma, Assistant Professor of Environmental Engineering at San Diego State University ([email protected]; 619-594-0957).

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D. Organizational Background

D.1. San Diego State University Research Foundation Established in 1943, the San Diego State University Research Foundation is a self-financed 501(c)(3) nonprofit corporation. As an auxiliary organization within the California State University (CSU) system, the San Diego State University Research Foundation is authorized by the Education Code of the State of California to provide and augment programs that are an integral part of the educational mission of San Diego State University. The purpose of San Diego State University Research Foundation is to further the educational, research and community service mission of San Diego State University. With over 5,800 employees, it is the largest auxiliary within the CSU system.

D.2. San Diego State University Founded in 1897, San Diego State University (SDSU) is the third largest university in California and has a student body of approximately 34,500. SDSU awards bachelors, masters, and doctoral degrees in more than 150 fields. SDSU offers the most doctoral degrees of any campus of the CSU system, currently in sixteen academic and research discipline. In research, SDSU has been ranked the No. 1 most productive research university for four years in a row, among schools with 14 or fewer Ph.D. programs based on the Faculty Scholarly Productivity Index (Academic Analytics, 2010).

D.3. Department of Civil, Construction and Environmental Engineering The Department of Civil, Construction and Environmental Engineering (Department) at SDSU offers bachelors degrees in Civil, Construction and Environmental Engineering, masters degrees in Civil, Construction and Environmental Engineering, and a Ph.D. degree in Civil and Environmental Engineering with the University of California at San Diego. Over the past five years, the enrolment at the Department has increased by more than double and currently about 700 students are enrolled into the various programs at Department.

Mission of the Department The mission of the Department is to provide a high quality undergraduate and graduate education in the civil, environmental, and construction engineering areas as well as the advising and other support needed to ensure the students’ academic success and preparation for a productive engineering career. In addition, through research and continuing professional development, the faculty produce, enhance and promote new developments within their areas of expertise for the benefit of society and the furtherance of their profession.

Educational Objectives The objectives of the Civil, Construction, and Environmental Engineering programs at the Department are to prepare graduates to practice in Civil, Construction, and Environmental Engineering by providing them with the ability to apply the basic principles of the mathematical, physical, and social sciences to the analysis and solution of Civil, Construction, and Environmental Engineering problems; to provide a basic understanding of issues faced during professional practice and a solid foundation for continuing education and graduate study.

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Research Active areas of research in the Department include construction, environmental, geotechnical, structural, transportation, and water resources engineering. The Department has well-equipped laboratories for experimental research in structural, geotechnical and geoenvironmental, environmental, transportation, and water resources engineering. In 2010, the faculty in the Department has attracted more than $2.5 million in external research grants.

Ongoing research projects in the Department that are related to water quality include:

• Developing innovative water and wastewater treatment technologies,

• Understanding the fate and effects of emerging contaminants in the environment,

• Developing treatment technologies for the removal of perchlorate from groundwater,

• Developing effective disinfection technologies for recycled water, and

• Compressible filters.

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E. Project Description

E.1. Water-Related Challenge Addressed by the Project Many water utilities in the U.S., including MWD and some of its member agencies, have been using or exploring ozone as an alternative disinfectant to comply with the stringent requirements of USEPA’s Disinfectants/ Disinfection Byproducts Rule (D/DBPR), which calls for lower concentrations of regulated Disinfection Byproducts (DBPs) than current regulatory levels. Although the use of ozone could reduce the formation of regulated DBPs (Huang et al., 2004), it could lead to the formation of other unregulated DBPs (Richardson, 2003). The goal of the proposed research is to address this challenge by investigating the formation of, and identifying potential precursors of, DBPs formed during ozonation of drinking water. To achieve this goal, the objectives of the research are: (1) to investigate the formation of an important class of DBPs, namely Halonitromethanes (HNMs), during ozonation and ozonation followed by chlorination and (2) to evaluate the effect of operational parameters, such as ozone and chlorine doses, ozone and chlorine contact times, and water quality in terms of pH and alkalinity, on HNM formation.

The focus of the project is local; however, the outcomes from the research can be adopted globally. The research will be conducted in the Environmental Engineering laboratories at SDSU. The laboratories occupy about 3000 square feet with research compartments dedicated to water quality, analytical instrumentation, chemical oxidation, microbiology and bioremediation. All the labs are well-equipped with the modern instrumentation required for physical, chemical, and microbiological analyses.

E.2. Background Disinfection is an important process in water treatment targeted mainly at removing disease causing microorganisms from water supplies. Chlorine is the most widely used disinfectant in the U.S. and several parts of the world because of its efficiency in killing harmful pathogens and its ability to provide residual disinfection in the distribution system. However, there is a growing concern regarding the use of chlorine due to the formation of numerous DBPs. DBPs are formed when chorine reacts with chemical species in water, referred to as DBP precursors. DBP precursors could be organic in nature such as natural organic matters (NOMs), or inorganic in nature, such as bromide and iodide ions (IPCS, 2000).

DBPs formed as a result of chlorination of drinking water has been a major regulatory issue in the U.S. since the Trihalomethanes (THMs) were first discovered in the early 1970s. In the past 40 years, a significant amount of research effort has been directed towards identifying and understanding DBPs, resulting in the identification of more than 700 DBPs (Krasner et al., 2006). However, only eleven DBPs (four THMs, five Haloacetic Acids (HAAs), bromate, and chlorite) are currently regulated under the USEPA’s D/DBPR (USEPA, 2009) .

Due to stringent requirements of Stage 2 D/DBPR issued by USEPA for allowable concentrations of DBPs in drinking water, many utilities in the U.S., including MWD (at Diemer, Jensen, Mills, and Skinner treatment plants) and its member agencies (Helix Water District, City of San Diego, City of Anaheim, San Diego County Water Authority, Calleguas Municipal Water District, and LADWP), have been using ozone as an alternative

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disinfectant. Ozone is often used as a primary disinfectant, while chlorine is used as a secondary disinfectant to provide residual disinfection in the distribution system (Richardson et al., 2007). Although the use of ozone could reduce the formation of THMs and HAAs (Huang et al., 2004), it could lead to the formation of other unregulated DBPs (Richardson, 2003). Therefore, obtaining a fundamental understanding about how DBPs form during ozonation and ozonation followed by chlorination and the factors controlling their formation is of critical importance to utilities using or considering ozonation as an alternative disinfectant.

In a nationwide occurrence study funded by the USEPA, approximately 50 DBPs that received the highest ranking for potential human health risks (i.e., high-priority DBPs) and that were not regulated under the USEPA’s D/DBPR were selected and monitored in drinking waters of twelve water treatment plants during 2000-2002 (Weinberg et al., 2002; Krasner et al., 2006). Two of these plants are located in EPA region 9 which includes Arizona, California, Hawaii and Nevada. Among the DBPs monitored, HNM species were detected at higher concentrations in samples from treatment plants using ozone as an alternative disinfectant. In the same study, nine HNM species (i.e., chloromethane (CNM), dichloronitromethane (DCNM), trichloronitromethane (TCNM), bromonitromethane (BNM), dibromonitromethane (DBNM), tribromonitromethane (TBNM), bromochloronitromethane (BCNM), bromodichloronitromethane (BDCNM), and dibromochloronitromethane (DBCNM)) received special attention because of their potential high toxicity and the level of occurrence in finished waters at some treatment facilities. However, the formation mechanisms and important precursors for these species still remain largely unknown. In this research, we propose to systematically study the formation of HNMs during ozonation and ozonation followed by chlorination from nitrogenous compounds commonly found in natural waters. In addition, we will identify optimal conditions (e.g., ozone and chlorine doses, ozone and chlorine contact times, pH and alkalinity) for formation of these HNMs during ozonation so that such conditions can be avoided in engineering practices.

E.3. Project Outcomes and Benefits There are several anticipated outcomes and benefits from the research. First, the results from the research will provide important information (e.g., factors controlling DBPs formation, potential precursors) for water utilities using or considering ozonation in the MWD service area and elsewhere. Second, the knowledge from the research will improve our understanding of the nature of HNMs formation (e.g., formation mechanisms) during ozonation and ozonation followed by chlorination and directly impact practicing engineers’ ability to control the formation of these compounds in water treatment facilities. Finally, the research results can be used by the USEPA and state regulatory agencies in developing procedures for managing these compounds to eliminate or lessen their risk to human health.

In addition, the data gathered in the research will be disseminated to the scientific community and water utilities. The primary mechanism for communication of the technical component of the research will be sharing the results with local water utilities as well as publication in peer-reviewed journals and presentation at local and national conferences. The Principal Investigator (PI) will also integrate components of the research into an undergraduate course. The PI teaches an undergraduate course, entitled ENVE 441 – Water Treatment Engineering. The goal of the course is to train students in the fundamental concepts of water treatment processes, design of water treatment units, water disinfection, DBPs control, and new and emerging water treatment

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OxygenTank

Ozone Generator

Flow Meter

FlowMeter

Ozone Analyzer

Aqueous OzoneProbe

Sample

To Exhaust

Ozone Analyzer

pH Sensor

Reaction Vessel

Fig. 1: Experimental Setup

technologies. Throughout the course of this research, the PI will incorporate elements of the project into the classroom, providing students the opportunity to participate in current research methodology and design.

The performance measures, quantitate/qualitative outcomes, and potential impacts of the project are summarized in the following table.

Performance Measure Quantitative/Qualitative

Outcome Impact

Provide critical information to water utilities using or consider ozone as alternative disinfectant

Identify factors controlling and potential precursors for DBPS formation

Local/ Global

Improve our understanding of the nature of HNMs formation during ozonation

Elucidate on the formation mechanisms of HNMs

Local/ Global

Adopted (long-term) by state or federal regulatory agencies to develop procedures for managing and controlling DBPs

Eliminate or lessen the risk associated with human health

Local/ Global

Integrate components of the research into an undergraduate course

About 30 students per semester enroll in the class

Local

Disseminate the findings of the research through publication in peer-reviewed journals and presentation at local and national conferences

Submit one article for publication in peer-reviewed journal and make a presentation at local and/or national conferences

Local/ Global

E.4. Research Design and Methods General Experimental Approach: The proposed research involves planning, designing and conducting a number of experiments. The experimental setup for the research (Fig. 1) consists of an oxygen tank, an ozone gas generator, a reaction vessel, and devices for influent and effluent ozone gas and aqueous ozone measurement. The reaction vessel has an internal diameter of 13 cm and a height of 30 cm, and it will be filled with 2.5 L of solution during each experiment. The reaction vessel is equipped with openings for ozone gas inlet and outlet, aqueous ozone probe, and sampling collection. Two glass diffusers will be used to

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sparge ozone gas into the solution at a constant flow rate. The reactor will operated in a semi-batch mode and the contents will be stirred continuously using a magnetic stirrer. The experiments will be conducted at room temperature.

During a typical experimental run, solution of target nitrogenous compounds (amino acids and amines) will be prepared in deionized water, and then the pH and alkalinity of the solution will be adjusted to desired value using dilute solutions of sulfuric acid (H2SO4) and/or sodium hydroxide (NaOH) and sodium bicarbonate (NaHCO3), respectively. Finally, ozone gas will be introduced into the solution and aliquot samples will be withdrawn periodically and analyzed for reaction intermediates and HNM species. For ozonation followed by chlorination treatment, the aliquot samples will be further treated with chlorination at desired concentration and contact time, and then analyzed for reaction intermediates and HNMs.

Analytical Methods: The influent and effluent ozone gas concentrations will be measured using M454 Ozone Analyzer (Teledyne Technologies, Inc., San Diego, CA) calibrated by the Potassium Iodide method. The aqueous ozone concentration will be determined using Q45H Dissolved Ozone Analyzer (Analytical Technology, Inc., Collegeville, PA) calibrated by the Indigo method. HNMs will be measured using USEPA Method 551.1. In the method, a 50 mL aliquot sample will be extracted with three mL of MTBE or five mL of pentane, and then two mL of the extract will be analyzed with an Agilent 6890 HP gas chromatograph (GC) equipped electron capture detector.

Materials: All chemicals, HNM standards, and reagents for the research will be analytical grade. Ozone gas will be generated from zero grade air (Praxair, Inc.) using LG-7 ozone generator (Ozone Engineering, Inc., El Sobrante, CA), and the amount of ozone produced in the oxygen gas will be controlled by changing power input to the generator

E.5. Research Tasks

Task # 1 – Investigate the Formation of Halonitromethanes (HNMs) during Ozonation and Ozonation Followed by Chlorination, and Identify their Potential Precursors

Task 1.1 – Select Model Nitrogenous Compounds: We will select model compounds from two types of nitrogenous organic compounds commonly detected in natural waters – amino acids and amines. We will select one or two model compounds from each group on the basis of their structure and similarity to HNM species, their reactivity with ozone and chlorine, and their expected reaction intermediates which may further react with ozone and chlorine to form HNMs.

Task 1.2 – Investigate the Formation of HNMs during Ozonation and Identify their Potential Precursors: In this task, we will systematically investigate the formation of HNMs from the model compounds selected in Task 1.1. As described in the experimental approach, we will prepare solution of each model compound at environmentally relevant concentrations; adjust the pH and alkalinity of the solution to values of 7.0 and 1.0 mM, respectively; and treat the solution with ozone gas dose of 1 mg/L. pH value of 7.0 and alkalinity of 1.0 mM are selected to mimic operational conditions at water treatment plants. We will collected aliquot samples at frequent time intervals; perform liquid-liquid extraction according to USEPA Method 551.1; and then analyze the extract for reaction intermediates and HNMs using a GC.

Task 1.3 – Investigate the Formation of HNMs during Ozonation Followed by Chlorination, and Identify their Potential Precursors: This task will mirror Task 1.2, varying only in that after ozonation, aliquot samples will be further treated with chlorine to simulate conditions at water

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treatment where ozone is often used as a primary disinfectant, while chlorine is used as a secondary disinfectant to provide residual disinfection in the distribution system. The chlorine treated sample will be subjected to liquid-liquid extraction according to USEPA Method 551.1, and the extract will be analyzed with a GC.

Task # 2 – Evaluate the Effect of Operational Parameters on HNM Formation We will systematically evaluate the influence of operational parameters, such as ozone and chlorine doses, ozone and chlorine contact times, and water quality in terms of pH and alkalinity, on HNM formation. We will vary these parameters so that their values bracket normal operational variations at water treatment plants. For example, pH values generally vary in the range of 6.5 to 7.5. To understand the effect of each parameter individually, we will change one parameter at a time while keeping others constant, and the process will be repeated until the influence of all operational parameters are tested. We will use the data to identify optimal conditions (ozone and chlorine doses, ozone and chlorine contact times, pH and alkalinity) that lead to the for formation of HNMs during ozonation or ozonation followed by chlorination so that such conditions can be avoided in engineering practices.

E.6. Project schedule The project duration is 10 months and detail timeline is given in the table below.

▼▼

PROJECT DURATION (months)RESEARCH ACTIVITIES 107 8 961 2 3 4 5

Task # 1 – Investigate the Formation of Halonitromethanes (HNMs) during Ozonation and Ozonation Followed by Chlorination, and Identify their Potential Precursors

Task # 2–Evaluate the Effect of Operational Parameters on HNM Formation

Task 1.1-Select Model Compounds

Research Activities

Task 1.3-Ozonation Followed by Chlorination

MWD Expo

Effect of Operational Parameters

Task 1.2-Ozonation

Project ReportPrepare Project Progress ReportPrepare Draft and Final Project Report

Prepare PowerPoint Slides for MDW Expo

F. Project Management Team The SDSU project team will work closely with MWD, other project sponsors, and the Helix Water District (a local water agency) on the project. We have assembled a well-qualified team with a number of years of research and professional experience. A brief highlight of the qualifications and responsibilities of each team members is presented below.

Temesgen Garoma, Ph.D., P.E. – Faculty Project Manager: Temesgen Garoma is an assistant professor in the Department of Civil, Construction and Environmental Engineering at SDSU. He holds Ph.D degree in environmental engineering, M.S. degree in geotechnical engineering, and B.S. degree in civil engineering. Dr. Garoma will be responsible for managing the project, providing technical guidance for the project team, planning and designing the experimental

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setup, overseeing the day to day activity of the project, and preparing draft and final project report. He has extensive research experience in the removal environmental pollutants from water using ozonation, advanced oxidation, and biological treatment processes. He has over ten years of professional experience and has been involved in the design of treatment processes for removal of pollutants from water and wastewater, master plan study for wastewater collection and water distribution systems, and feasibility study for recycled water projects.

Mark Umphres, P.E. – Local Water Agency Representative: Mr. Umphres has worked in the water industry for 35 years as a private engineering consultant and public water agency employee. Mr. Umphres was a vice president and regional manager of a San Diego-based consulting engineering office serving public water agencies in southern California. He has served on a number of water-related technical committees and taught as an adjunct instructor for two local community college water treatment certification programs. He is currently the Director of Water Quality and System operations for the Helix Water District. In this position he is responsible for the operation and maintenance of the District’s water treatment plant, reservoirs and distribution system tanks and pump stations. He is also the director of the District’s water quality laboratory.

The Helix Water District, an MWD member agency, owns and operates a 106 mgd capacity water treatment plant. The District has been using ozone as a disinfectant for about ten years. The District covers an area of nearly 50 square miles, serving the cities of La Mesa, El Cajon, Lemon Grove, the community of Spring Valley, and various unincorporated areas near El Cajon.

Youxian Wu, Ph.D. – Director of Environmental Engineering Laboratories: Dr. Wu will be responsible for overall management of sample collection, sample analysis, instrument operation and maintenance, and student training in instrument operation. He has extensive experience in water quality monitoring, water quality analysis, and used state-of-the-art analytical instrumentations (GC/MS, LC/MS, GC/FID, ICPMS, TOC, HPLC, etc). Cintia Lau – Student Project Manager: Cintia is an undergraduate student in the environmental engineering program at SDSU. She will be responsible for sample collection, lab experiments, and data analysis.

Tisha Martz – Project Administrator: Tisha will handle project administration activities, such as budget control, student timesheet, and purchase of supplies.

Name Title/

Organization Address

Phone & E-mail

Temesgen Garoma

Assistant Professor/ San Diego State University

5500 Campanile Drive, San Diego, CA 92182

619-594-0957/ [email protected]

Mark Umphres

Director of Water Quality and System Operations / Helix Water District

9550 Lake Jennings Park Road, Lakeside, CA 92040

619-667-6242/

[email protected]

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Youxian Wu

Director of Environmental Engineering laboratories/ San Diego State University



Cintia Lau

Student Project Manager/ San Diego State University



Tisha Martz

Project administrator/ San Diego State University

5250 Campanile Drive San Diego, CA 92182


G. Certification of Attendance Cintia Lau and Kai Chan have attended the October 7th outreach event representing SDSU and the certificates are attached with the proposal.

H. Project Budget and Breakdown The total cost of the project is $13,591 and we are requesting $10,000 from MWD. The rest will be covered through forgone indirect cost at a rate 39.5% (49.5%- 10%) of the total direct cost, which is equivalent to $3,591. Our total proposed match for the project is 35.9% of the total grant requested.

Project Fund

Description Amount Notes

Grant funds requested $10,000 Requested from MWD

Matching fund $3,591 Forgone indirect cost

Project Total $13,591 Total project cost

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Typewritten Text

Helix WD

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Literature Cited Huang, W.-J., Chen, L.-Y., and Peng, H.-S. (2004) Effect of NOM characteristics on brominated

organics formation by ozonation. Environment International 29: 1049-1055.

IPCS (2000) Disinfectants and Disinfectant Byproducts. In. Geneva: World Health Organization.

Krasner, S.W., Weinberg, H.S., Richardson, S.D., Pastor, S.J., Chinn, R., Sclimenti, M.J. et al. (2006) Occurrence of a new generation of disinfection byproducts. Environmental Science & Technology 40: 7175-7185.

Richardson, S.D. (2003) Disinfection by-products and other emerging contaminants in drinking water. Trac-Trends in Analytical Chemistry 22: 666-684.

Richardson, S.D., Plewa, M.J., Wagner, E.D., Schoeny, R., and DeMarini, D.M. (2007) Occurrence, genotoxicity, and carcinogenicity of regulated and emerging disinfection by-products in drinking water: A review and roadmap for research. Mutation Research-Reviews in Mutation Research 636: 178-242.

USEPA (2009) RegulationsNational Primary Drinking Water RegulationsNational Primary. In.

Weinberg, H.S., Krasner., S.W., and Richardon, S.D. (2002) The Occurrence of Disinfection Byproduct (DBPs) of Health Concern: Results of a Nationwide DBP Occurrence Study. In. Athens, GA: USEPA, EPA/600/R-02/068.

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