USF Libraries
USF Digital Collections

Comparison of the use of single and multiple oxidants on the generation of particulate matter in water distribution syst...

MISSING IMAGE

Material Information

Title:
Comparison of the use of single and multiple oxidants on the generation of particulate matter in water distribution systems derived from groundwater sources containing hydrogen sulfide and dissolved organics
Physical Description:
Book
Language:
English
Creator:
Minnis, Rochelle J
Publisher:
University of South Florida
Place of Publication:
Tampa, Fla
Publication Date:

Subjects

Subjects / Keywords:
Turbidity
UV irradiation
Chlorine
Chloramine
Particle count
Dissertations, Academic -- Environmental Engineering -- Masters -- USF
Genre:
bibliography   ( marcgt )
theses   ( marcgt )
non-fiction   ( marcgt )

Notes

Abstract:
ABSTRACT: Due to increasingly stringent regulations, concerns about disinfection byproduct formation, and the need for improved control of distribution system water quality, there has been a shift towards the use of alternative disinfectants and oxidants in the production of drinking water. Technologies that modify water chemistry, such as hydrogen peroxide, UV irradiation, chlorine and/or chloramines may result in the generation of mineral and organic precipitates. Turbidity provides an indirect measure of the presence of particles by evaluating the light scattering properties of water. Turbidity levels are currently not monitored or regulated in treated groundwater. An important water quality parameter that influences groundwater quality is hydrogen sulfide. The control of sulfides in groundwater is of importance because its presence can cause odor and taste complaints, corrosion of pipes and other plumbing fixtures, and black-water problems in distribution systems (Levine et. ^al, 2004). In addition, sulfides can impose a significant oxidant demand and possibly interfere with disinfection treatments. Characteristics of particles from untreated and treated groundwater were tested as part of a field study to evaluate alternative wellhead treatment approaches for controlling hydrogen sulfide. A 1 gallon per minute (gpm) pilot-plant was used to test several groundwater treatment scenarios. The chemicals tested included chlorine, monochloramine, and hydrogen peroxide either alone or in tandem. Photochemical oxidation was evaluated using UV and advanced oxidation was evaluated using hydrogen peroxide coupled with UV. Testing was conducted either on water pumped directly from the well at ambient (7.0-7.5), or pretreated with caustic soda to evaluate the impact of elevated pH (8.2) conditions. The formation of particles was quantified using turbidity, solids (total, dissolved and suspended), and particle counts before and after oxidation. The particulate matt er was characterized using a particle size analyzer in conjunction with scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). Treatment systems that rely on in-line treatment lack mechanisms for particle removal, therefore particles generated through treatment are introduced into the distribution system. It is evident from this project that treatment systems should be optimized to prevent particle formation.
Thesis:
Thesis (M.S.)--University of South Florida, 2005.
Bibliography:
Includes bibliographical references.
System Details:
System requirements: World Wide Web browser and PDF reader.
System Details:
Mode of access: World Wide Web.
Statement of Responsibility:
by Rochelle J. Minnis.
General Note:
Title from PDF of title page.
General Note:
Document formatted into pages; contains 145 pages.

Record Information

Source Institution:
University of South Florida Library
Holding Location:
University of South Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 001913675
oclc - 174144064
usfldc doi - E14-SFE0001390
usfldc handle - e14.1390
System ID:
SFS0025710:00001


This item is only available as the following downloads:


Full Text

PAGE 1

Comparison of the Use of Single and Multiple Oxidan ts on the Generation of Particulate Matter in Water Distribution Systems Derived from G roundwater Sources Containing Hydrogen Sulfide and Dissolved Organics by Rochelle J. Minnis A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Environmental Engineering Department of Civil and Environmental Engineering College of Engineering University of South Florida Major Professor: Audrey D. Levine, Ph.D. Carlos A. Smith, Ph.D. Carl Biver, Ph.D. Date of Approval: November 8, 2005 Keywords: turbidity, uv irradiation, chlorine, chlo ramine, particle count Copyright 2005, Rochelle J. Minnis

PAGE 2

Dedication I would like to dedicate this thesis to my family, especially my father, Mr. Randolph J. Minnis, my mother, Mrs. Julieth N. Minn is, and my sister Roya J. Ndimba. Without their support, encouragement and faith in m y abilities, this thesis would not have been written.

PAGE 3

Acknowledgements Primarily, I would like to thank my major professor Dr. Audrey D. Levine for her support and guidance over the past two years. She introduced me to the world of environmental engineering and that is a gift beyond measure. Her wealth of knowledge about environmental issues is outstanding and her d edication to her students is commendable. Her belief in my abilities allowed me to continue on this journey in spite of my own lagging confidence and many tearful days. I would also like to thank Dr. Carlos A. Smith, and Dr. Carl Biver, for their guidance and encouragement while I pursued both my BSc. in Chemical Engineering and MSc. in Environmental Engineering. Special thanks go out to Salah Albustami and Camilo Romero who were with me in the field every day, in good weather and bad. W ithout you guys, there would be no data for this thesis. I want to thank the staff in the USF Environmental Engineering lab for their help with the laboratory tests and David Edwards from the USF Center for Ocean Technology/MEMS Lab for his help with the SEM and EDS analyses. I want to thank the staff of Aloha Utilities especi ally Mike McDonald, Charlie Painter, and Jack Burke for the construction of pil ot plant and help with start-up and operation.

PAGE 4

i Table of Contents List of Tables..................................... ................................................... .............................iv List of Figures.................................... ................................................... .............................ix Abstract........................................... ................................................... ................................xi Introduction....................................... ................................................... ...............................1 Objectives......................................... ................................................... ...............................3 Background......................................... ................................................... .............................4 Groundwater Quality in Florida..................... ................................................... ......4 Sulfide Chemistry.................................. ................................................... ..............8 Sulfide Control in Groundwater..................... ................................................... ......9 Chlorine Oxidation of Sulfide...................... .............................................11 Hydrogen Peroxide Oxidation of Sulfide............. ....................................12 Ultraviolet (UV) Irradiation....................... ...............................................13 Hydrogen-Peroxide/UV Advanced Oxidation Process.... .........................13 Particles in Groundwater........................... ................................................... .........14 Types of Particles Found in Groundwater............ ....................................15 Causes of Particle Presence in Groundwater......... ...................................15

PAGE 5

ii Particle Characterization Methods.................. ................................................... ...16 Turbidity.......................................... ................................................... ......17 Particle Count and Size Distribution............... ..........................................18 Scanning Electron Microscopy (SEM)................. ....................................18 Article 1: Potential for Colloidal Particle Formati on Resulting from Groundwater Disinfection....................................... ................................................... ............19 Abstract........................................... ................................................... ...................19 Introduction....................................... ................................................... .................20 Background......................................... ................................................... ...............25 Methods............................................ ................................................... ..................27 Results and Discussion............................. ................................................... .........34 Conclusions........................................ ................................................... ................41 Acknowledgements................................... ................................................... .........42 Article 2: A Pilot Study Used to Evaluate In-Pipe C ontrol of Hydrogen Sulfide for Wellhead Treatment of Groundwater...................... .................................................43 Abstract........................................... ................................................... ...................43 Introduction....................................... ................................................... .................44 Background......................................... ................................................... ...............46 Sulfide in Groundwater............................. ................................................46 Treatment Alternatives for the Control of Hydrogen Sulfide...................48 Oxidation.......................................... .............................................48 Hydrogen Peroxide Oxidation of Hydrogen Sulfide.... ....49 Hydrogen-Peroxide/UV Advanced Oxidation Process.... .50 Methods............................................ ................................................... ..................51

PAGE 6

iii Experimental Design................................ .................................................52 Analytical Tests................................... ................................................... ..53 Hydrogen Peroxide Determination.................... .......................................53 Bench-Scale Tests.................................. ................................................... 55 Pilot Plant Design................................. ................................................... .55 Results and Discussion............................. ................................................... .........57 Bench-Scale Tests.................................. ................................................... 58 Pilot Scale Tests.................................. ................................................... ...59 Conclusions & Recommendations...................... ..................................................6 4 Acknowledgements................................... ................................................... .........64 Conclusions........................................ ................................................... ............................65 Engineering Implications........................... ................................................... ....................67 Recommendations for Further Research............... ................................................... .........69 References......................................... ................................................... .............................72 Bibliography....................................... ................................................... ...........................75 Appendices......................................... ................................................... ............................77 Appendix A: Pilot Plant Design and Operation....... ................................................... ......78 Appendix B: Procedure for Hydrogen Peroxide Measure ment........................................84 Appendix C: Bench Scale and Pilot Plant Data....... ................................................... ......88 Appendix D: Laboratory Tests....................... ................................................... ..............127

PAGE 7

iv List of Tables Table 1: Summary of the five major requirements pro posed by the GWR........................5 Table 2: Comparison of regulations pertain to parti cles and disinfection rules in groundwater and surface water treatment............ .................................................7 Table 3: Values of K2 obtained from various sources..................... ...................................8 Table 4: Factors that influence particle formation. ................................................... ........15 Table 5: Chlorine oxidation of iron, manganese, and hydrogen sulfide...........................22 Table 6: Comparison of regulations pertaining to pa rticles and disinfection rules in groundwater and surface water treatment......... .............................................24 Table 7: Potential forms of mineral precipitates in groundwater and their corresponding solubility products at 25C.......... ...............................................26 Table 8: Detention times of reactors............... ................................................... ...............28 Table 9: Summary of analytical parameters tested... ................................................... .....31 Table 10: Summary of untreated water quality data f rom a groundwater source in west-central Florida (2004-2005 monitoring data)... ........................................34 Table 11: Affect of disinfection treatment on water quality parameters at pH 8.2..........36 Table 12: Affect of pH on total particle count..... ................................................... ..........39

PAGE 8

v Table 13: Secondary drinking water standards set fo r compounds that contribute to odor and taste problems......................... ................................................... ....44 Table 14: Summary of FDEP treatment recommendations for control of total sulfide in new or altered wells (adapted from FDEP Chapter 62-555.315 (5))............................................... ................................................... ..................45 Table 15: Values of K2 obtained from various sources..................... ...............................47 Table 16: Summary of bench-scale and pilot-scale te sts conducted.................................52 Table 17: Summary of analytical parameters tested.. ................................................... ....54 Table 18: Detention times of reactors.............. ................................................... ..............56 Table 19: Summary of untreated water quality data f rom a groundwater source in west-central Florida (2004-2005 monitoring data)... ........................................57 Table 20: Prediction of elemental sulfur produced a t ambient pH...................................61 Table 21: Prediction of elemental sulfur produced a t pH 8.2........................................... 61 Table 22: Prediction of elemental sulfur produced d uring chlorination after hydrogen peroxide addition......................... ................................................... ..63 Table A 1: Detention times of reactors………………………………… ……………….. 80 Table C 1: Peroxide sulfide ratio = 1:1 (well 9)... ................................................... .........90 Table C 2: Peroxide sulfide ratio 2:1 (well 9)..... ................................................... ...........90 Table C 3: Peroxide sulfide ratio 3:1 (well 9)..... ................................................... ...........91 Table C 4: Peroxide sulfide ratio 4:1 (well 9)..... ................................................... ...........92 Table C 5: Peroxide sulfide ratio 5:1 (well 9)..... ................................................... ...........93 Table C 6: Peroxide sulfide ratio 6:1 (well 9)..... ................................................... ...........94

PAGE 9

vi Table C 7: Chlorine demand data for well 1 at ambie nt pH.............................................9 4 Table C 8: Chlorine demand data for well 1 at pH 8. 3.................................................. ...95 Table C 9: Chlorine demand data for well 2 at ambie nt pH.............................................9 5 Table C 10: Chlorine demand data for well 2 at pH 8 .3................................................. ..96 Table C 11: Chlorine demand data for well 3 at ambi ent pH...........................................96 Table C 12: Chlorine demand data for well 3 at pH 8 .3................................................. ..97 Table C 13: Chlorine demand data for well 4 at pH 8 .3................................................. ..97 Table C 14: Chlorine demand data for well 6 at ambi ent pH...........................................97 Table C 15: Chlorine demand data for well 6 at pH 8 .3................................................. ..98 Table C 16: Chlorine demand data for well 7 at ambi ent pH...........................................98 Table C 17: Chlorine Demand data for well 7 at pH 8 .3................................................. .99 Table C 18: Chlorine demand data for well 8 at ambi ent pH...........................................99 Table C 19: Chlorine demand data for well 8 at pH 8 .3................................................. 100 Table C 20: Chlorine demand data for well 9 at ambi ent pH.........................................100 Table C 21: Chlorine demand data for well 9 at pH 8 .3................................................. 100 Table C 22: Combined peroxide, chlorine and ammonia runs at well 2 10/20/2004.....101 Table C 23: Combined peroxide chlorine and ammonia runs at well 3 11/10/2004 at pH 7.8.......................................... ................................................... .........102 Table C 24: Combined peroxide, chlorine and ammonia runs at well 3 11/10/2004 at pH 7.8.......................................... ................................................... .........103

PAGE 10

vii Table C 25: Combined peroxide, chlorine and ammonia runs at well 4 11/11/2004 at pH 7.8.......................................... ................................................... .........104 Table C 26: Combined peroxide, chlorine and ammonia runs at well 4 11/11/2004 at pH 8.2.......................................... ................................................... .........106 Table C 27: Combined peroxide, chlorine and ammonia runs at well 8 10/19/2004 at pH 8.3.......................................... ................................................... .........107 Table C 28: Combined peroxide chlorine and ammonia runs at well 9 10/18/2004 at pH 8.3.......................................... ................................................... .........109 Table C 29: Field tests to test oxidant combination s at ambient pH 8/15/2005.............111 Table C 30: Field tests to test oxidant combination s at pH 8.2 8/23/2005....................115 Table C 31: Field tests to test oxidant combination s at ambient pH 9/5/2005..............119 Table C 32: Field tests to test oxidant combination s at pH 8.2 9/10/2005....................123 Table D 1: Total solids............................ ................................................... .....................129 Table D 2: Total dissolved solids, mg/L............ ................................................... ..........130 Table D 3: Size distribution of raw water particles 8/16/2005.......................................13 1 Table D 4: Size distribution of particles after hyd rogen peroxide treatment at ambient pH 8/16/2005............................... ................................................... .132 Table D 5: Size distribution of particles after hyd rogen peroxide-UV treatment at ambient pH 8/16/2005............................... ................................................... .133 Table D 6: Size distribution of particles after hyd rogen peroxide-UV-chlorineammonia treatment at ambient pH 8/16/2005.......... .....................................134 Table D 7: Size distribution of particles after hyd rogen peroxide-UV-chlorine treatment at ambient pH 8/16/2005.................. .............................................135

PAGE 11

viii Table D 8: Size distribution of particles after hyd rogen peroxide-chlorine treatment at ambient pH 8/16/2005.................. .............................................136 Table D 9: Size distribution of particles after hyd rogen peroxide-chlorine treatment at ambient pH 8/16/2005.................. .............................................137 Table D 10: Size distribution of particles after UV treatment at ambient pH 8/16/2005.......................................... ................................................... .......138 Table D 11: Size distribution of particles after UV -chlorine treatment at ambient pH 8/16/2005....................................... ................................................... ....139 Table D 12: Size distribution of particles after UV -chlorine-ammonia treatment at ambient pH 8/16/2005............................... ..................................................1 40 Table D 13: Size distribution of particles after ch lorine treatment at ambient pH 8/16/2005.......................................... ................................................... .......141 Table D 14: Size distribution of particles after ch lorine-ammonia treatment at ambient pH 8/16/2005............................... ..................................................1 42 Table D 15: Size distribution of particles at eleva ted pH 8/23/2005..............................143 Table D 16: Size distribution of particles at ambie nt pH 9/5/2005................................144 Table D 17: Size distribution of particles at eleva ted pH 9/10/2005..............................145

PAGE 12

ix List of Figures Figure 1: Theoretical distribution of sulfide speci es in water as a function of pH.............9 Figure 2: pE-pH equilibrium diagram for thermodynam ically stable sulfur species........10 Figure 3: Schematic of pilot plant................. ................................................... .................29 Figure 4: Response of turbidity to sulfide levels i n well 9........................................... ....35 Figure 5: Turbidity formed as a result of disinfect ion treatment...................................... 37 Figure 6: Comparison of % total and suspended solid s from disinfection treatments......................................... ................................................... ..............38 Figure 7: Scanning electron micrographs of particle s in untreated groundwater. The approximate size of the particles are a) 2 micr ons b) 3 microns c) 3 microns and d) 15 microns.......................... ................................................... ...40 Figure 8: Scanning electron micrographs of particle s in treated groundwater.................41 Figure 9: Scanning electron micrographs of microorg anisms in groundwater that are attached to particulate matter................. ................................................... ..41 Figure 10: Illustration of sulfide equilibrium in t erms of pH......................................... ..47 Figure 11: pE-pH equilibrium diagram for thermodyna mically stable sulfur species (Thermodynamic constants from Stumm and Mor gan 1999)............49

PAGE 13

x Figure 12: Hydrogen sulfide removal using a hydroge n peroxide to hydrogen sulfide ratio of 1:1............................... ................................................... .........58 Figure 13: % Sulfide removal at ambient and elevate d pH levels....................................59 Figure 14: Average turbidity values for ambient pH and pH 8.2.....................................62 Figure 15: Average turbidity values after chlorine addition at ambient pH and pH 8.2................................................ ................................................... .................63 Figure A 1: Schematic of pilot plant unit……………..... .................................................79 Figure A 2: Results from tracer tests for a) the en tire pilot plant and b) the individual reactors................................ ................................................... ......82

PAGE 14

xi Comparison of the Use of Single and Multiple Oxidan ts on the Generation of Particulate Matter in Water Distribution Systems De rived from Groundwater Sources Containing Hydrogen Sulfide and Dissolved O rganics Rochelle J. Minnis ABSTRACT Due to increasingly stringent regulations, concerns about disinfection byproduct formation, and the need for improved control of dis tribution system water quality, there has been a shift towards the use of alternative dis infectants and oxidants in the production of drinking water. Technologies that modify water chemistry, such as hydrogen peroxide, UV irradiation, chlorine and/or chloramin es may result in the generation of mineral and organic precipitates. Turbidity provid es an indirect measure of the presence of particles by evaluating the light scattering pro perties of water. Turbidity levels are currently not monitored or regulated in treated gro undwater. An important water quality parameter that influence s groundwater quality is hydrogen sulfide. The control of sulfides in groun dwater is of importance because its presence can cause odor and taste complaints, corro sion of pipes and other plumbing

PAGE 15

xii fixtures, and black-water problems in distribution systems (Levine et. al, 2004). In addition, sulfides can impose a significant oxidant demand and possibly interfere with disinfection treatments. Characteristics of particles from untreated and tre ated groundwater were tested as part of a field study to evaluate alternative wellh ead treatment approaches for controlling hydrogen sulfide. A 1 gallon per minute (gpm) pilot -plant was used to test several groundwater treatment scenarios. The chemicals tes ted included chlorine, monochloramine, and hydrogen peroxide either alone or in tandem. Photochemical oxidation was evaluated using UV and advanced oxida tion was evaluated using hydrogen peroxide coupled with UV. Testing was conducted ei ther on water pumped directly from the well at ambient (7.0-7.5), or pretreated with c austic soda to evaluate the impact of elevated pH (8.2) conditions. The formation of par ticles was quantified using turbidity, solids (total, dissolved and suspended), and partic le counts before and after oxidation. The particulate matter was characterized using a pa rticle size analyzer in conjunction with scanning electron microscopy coupled with ener gy dispersive spectroscopy (SEM/EDS). Treatment systems that rely on in-line treatment la ck mechanisms for particle removal, therefore particles generated through trea tment are introduced into the distribution system. It is evident from this proje ct that treatment systems should be optimized to prevent particle formation.

PAGE 16

1 Introduction The presence of particulate matter in water systems is of importance because particles in water may be comprised of microorganis ms (EPA Guidance Manual, 1999) or inert organic or inorganic constituents. The pr esence of particles may act to shield pathogens (viruses, bacteria, and protozoa) from th e action of disinfectants (chlorine, ozone, UV irradiation). Particulate matter can als o provide surface area for accumulation of microbial substrates and biofilms (EPA Guidance Manual, 1999). There has been a shift in the drinking water indust ry towards the use of alternative treatments because of the need for improved control of distribution system water quality. The use of these alternative treatments can modify water chemistry and may impact the concentration of particulate matter in treated wate r. The impact that these treatments have on particle type and concentration needs to be addressed to develop proper engineering control strategies. One of the major water quality factors that control s the solubility of particles in water is pH. pH also impacts the degree of sulfur ionizatio n which influences the effectiveness of

PAGE 17

2 removal pathways and the end products of oxidation reactions. At pH levels below 7.5, sulfur formation is favored whereas above 7.5, sulf ate is the preferred product. Many water treatment plants adjust the pH and alkalinity of water in order to meet specific corrosion indices such as the Langelier index. The refore, the impact that disinfectants and oxidants have on particle characteristics at di fferent pH levels needs to be understood.

PAGE 18

3 Objectives This research project was conducted to evaluate the degree to which particulate matter is generated as a byproduct of groundwater t reatment for the control of hydrogen sulfide. The specific objectives are: 1. Evaluate the impact of disinfection on the formatio n or dissolution of mineral and organic particles at ambient and elevated pH levels 2. Compare alternative oxidation technologies for the control of hydrogen sulfide in groundwater at ambient and elevated pH levels.

PAGE 19

4 Background Background information on ground water quality is p rovided in this section. Two parameters that affect water quality are discussed: hydrogen sulfide and the presence of particles. Methods for sulfide removal appropriate for small water systems are summarized. Groundwater Quality in Florida More than 90 percent of Floridians rely on groundwa ter as their source for drinking water. In 2000, the United States Environ mental Protection Agency (USEPA) proposed the Groundwater Rule (GWR) to regulate all groundwater sources that supply drinking water. This regulation is intended to pro tect public health by reducing the potential for exposure to microbial contaminants in drinking water (USEPA, 2005). The major components of the GWR are outlined in Table 1 (USEPA, 2000). The emphasis of the requirements is in monitoring for fecal contami nation and designing disinfection systems to provide the capability of 4-log inactiva tion or removal of viruses (USEPA, 2000).

PAGE 20

5 Table 1: Summary of the five major requirements pro posed by the GWR Component Explanation Frequency Periodic Sanitary Surveys of Groundwater Systems The Sanitary survey evaluates and documents the strengths and weaknesses of the water system’s sources, treatment, storage, distribution, network, operation and maintenance, and overall management. Once every three years for community water systems and at least once every five years for non-community water systems Hydrogeological Assessments of wells Identifies groundwater wells that are sensitive to fecal contamination. The GWR identifies three aquifer types that are sensitive: Karst, fractured bedrock, and gravel aquifers. One test for each groundwater system that does not provide treatment to 4-log inactivation or removal of viruses is required and should be conducted before three years or five years elapse after publication of the Final Rule in the Federal Register for community water systems and non community water systems respectively. Source Water Monitoring Identifies the systems with source water contamination and systems with high sensitivity to possible fecal contamination by testing for total coliforms. EPA requests comment on monitoring frequency Corrective Treatment Systems must eliminate the source of contamination, correct the significant deficiency, provide an alternative source water, or provide a treatment to achieve a 99.99 percent (4-log) inactivation or removal of viruses. Must apply an appropriate treatment technique within 90 days of detection of the significant deficiency or source water contamination. If unable to do so, they must have a State-approved plan and schedule for doing so. Compliance Monitoring Ensures that disinfection treatment is reliably operated where it is used. EPA requests comment on monitory frequency.

PAGE 21

6 Until the GWR is implemented, groundwater disinfect ion is governed by monitoring for indicator bacteria in the distributi on system and must meet appropriate regulations under the Safe Drinking Water Act (SDWA ) for primary and secondary contaminants. A summary of other regulatory requir ements is outlined in Table 2 (USEPA, 2000). Hydrogen sulfide and the presence o f particulates in water are not directly addressed in any of the current regulation s.

PAGE 22

Table 2: Comparison of regulations pertain to parti cles and disinfection rules in groundwater and surf ace water treatment Regulations Existing or Future Date Anticipated for Final Rule Description Monitored at Treatment Plant or Distribution System Total Coliform Rule (TCR) Existing (1989), but under revision. TCR monitors for the presence of total and fecal coliform. Presence indicates that other harmful bacteria may be present. The total number and location of samples is based on the population served. Distribution System Lead & Copper Rule (LCR) Revised in 2000 LCR sets maximum contaminant levels (MCLs) for lead (0.015mg/L) and copper (1.3 mg/L) based on the 90th percentile level of tap water samples. Distribution System Long Term 2 Enhanced Surface Water Treatment Rule July 2005 Requires monitoring for large systems (>10,000 people) of Cryptosporidium for two years to characterize water quality. Then depending on the concentration, methods of removal in addition to conventional treatment and filtering will have to be implemented. Small systems (< 10,000 people), monitor E.Coli. Treatment Plant stage 2 disinfectants/disinfection byproducts rule July 2005 Regulates the disinfectant concentration and disinfection byproduct amounts in treated water. Large and medium systems must comply with 0.0080/0.060mg/L TTHM/HAA5 LRAA six years after promulgation and after ten years for small systems Distribution System a,bOnly applies to groundwater sources that are under the direct influence of surface water 7

PAGE 23

8 Sulfide Chemistry Sulfur exists in nine oxidation states in water and can transition from one state to another depending on localized chemical and biologi cal reactions. Sulfides in water are undesirable because of their “rotten egg” odor and their corrosivity properties (Dohnalek, 1983). The term “total sulfides” refer to dissolve d hydrogen sulfide (H2S), ionized sulfide (HSand S2-), and acid-soluble metallic sulfides, and polysulf ides. The equilibrium equations for the three sulfide species are outlined in equations 1 and 2 and illustrated in Figure 1 with respect to pH. Variou s values have been reported for the second equilibrium constant at 25C. A summary of values is given in Table 3. + -+ H HS S H2 ( ) ( ) () S H H HS K2 7 110+ -= = at C T20 = (1) + -+ H S HS2 ( ) ( ) + -= HS H S K2 2 at C T20= (2) Table 3: Values of K2 obtained from various sources Source Benjamin, 2002 Garrels, et.al, 1965 Sillen, et. al 1964 Knox, 1906 Maronny, 1959 Value 10-12.92 10-14 10-17.1 10-14.92 10-13.78 The speciation of reduced sulfur in water is contro lled mainly by pH as shown in Figure 1. The form of reduced sulfur in water dict ates the effectiveness of the type of treatment used. The non-ionized form of reduced su lfur (hydrogen sulfide) is very volatile and is mostly present at the pH levels bel ow six. Thus, the use of aeration can be

PAGE 24

9 more effective for stripping the volatile form of h ydrogen sulfide from water. The pH levels of most water sources range from approximate ly 6.5 to 8.5. Above a pH of 8 bisulfide (HS-) is the prevalent form of reduced sulfur. Polysul fides (Sn 2-) are prevalent above the second equilibrium constant (see Table 3) 0 20 40 60 80 100 02468101214 pHDistribution of Reduced S, %H2S HSS2pH Range of Source Water Figure 1: Theoretical distribution of sulfide speci es in water as a function of pH Sulfide Control in Groundwater Methods for sulfide control in groundwater include aeration, oxidation (biological or chemical), and anion exchange. The following se ction discusses the use of oxidation for sulfide control.

PAGE 25

10 The addition of oxidants such as chlorine, hydrogen peroxide or ozone to groundwater serves to increase its oxidation potent ial because of reactions with reduced constituents in water. The extent of the change in oxidation potential is influenced by the reaction rates. By manipulating the pH and the dos ages of chemical oxidants, the oxidation potential and end products of sulfur oxid ation can be controlled. This is illustrated in Figure 2. -10 -5 0 5 10 15 20 246810 pHpEH2S SO4 -2HS-SH2O O2H2 Oxidantaddition pH Control Oxidantaddition Figure 2: pE-pH equilibrium diagram for thermodynam ically stable sulfur species

PAGE 26

11 Chlorine Oxidation of Sulfide Chlorine is widely used in water treatment as a dis infectant. Because chlorine is a strong oxidant, it can oxidize reduced forms of sul fide. Chlorine is added to water as gaseous chlorine (Cl2), or liquid chlorine (sodium hypochlorite). Sodiu m hypochlorite disassociates in water according to reaction (4). ++ OCl Na NaOCl (4) The OClion then reacts with H2S or HSto form sulfur or sulfate according to reactions (5)-(8) (Lyn, 1992). O H Cl S S H OCl2 0 2+ + +(5) -+ + + OH Cl S HS OCl0 (6) + -+ + + Cl H SO S H OCl 4 2 42 4 2 (7) + -+ + + Cl H SO HS OCl 4 42 4 (8) Reactions (5) and (6) are more likely to occur at p H levels below 7.5 while reactions (7) and (8) are more likely to occur above pH 7.5 (Cade na, 1988). According to a study conducted by Lyn and Taylor on a water source in Pinellas County, Florida, one of the side effects of using c hlorine for the oxidation of sulfide is that it always produces turbidity in the treated wa ter. However, while elevated turbidity

PAGE 27

12 levels were noted in their study, no particle analy sis was ever done to verify that the turbidity was indeed caused by sulfur precipitation Hydrogen Peroxide Oxidation of Sulfide Hydrogen peroxide is a powerful oxidant with an oxi dation potential of -1.76V (Dohnalek, 1983). Only a few other oxidizers excee d the power of peroxide, such as elemental fluorine, ozone, peroxodisulfate (Dohnale k, 1988), and peroxide coupled with UV irradiation, ozone, or iron to yield hydroxyl ra dicals. Several benefits that are associated with using hydrogen peroxide include: it breaks down into oxygen and water, it does not contribute to disinfection-by-products, and it is neither toxic nor corrosive (Dohnalek, 1988). The reactions that can occur bet ween hydrogen peroxide and sulfide are shown in equations (9) and (10) (Dohnalek, 1988 ). Limited data are available on the kinetics of these reactions in groundwater (Black, 1952, Hoffman, 1977, Levine, 2004). 0 2 2 2 8 1 2 S O H H O H HS + + ++ pH < 8.0 (9) + -+ + + H O H SO O H HS2 2 4 2 24 4 pH > 8.0 (10)

PAGE 28

13 Ultraviolet (UV) Irradiation UV irradiation can be an effective disinfectant. I t is widely used in wastewater disinfection. UV can also reduce sulfides in groun dwater through photolysis. Most UV lamps operate at a maximum energy output of 253.7 n m, which provides for inactivation of microorganisms in the water. Because of the lac k of residual left in the water after UV irradiation, it is often used in conjunction with o ther oxidants such as hydrogen peroxide, ozone, or chlorine. These treatments are known as advanced oxidation processes. It can also be used as a primary disinfectant, followed by chlorine or chloramines as secondary disinfectants. Hydrogen-Peroxide/UV Advanced Oxidation Process Hydrogen peroxide in conjunction with UV irradiatio n is an advanced oxidation process that is widely used for oxidation of organi c contaminants in groundwater. The UV reacts with hydrogen peroxide to form hydroxyl r adicals which are more powerful than any other oxidant used for hydrogen sulfide ox idation. The oxidation potential of hydroxyl radicals is 2.8V (U.S. Peroxide, 2005). G laze et. al. gave the following reactions as a proposed pathway that may be used fo r this process (equations 11a-11f). OH hv O H + 22 2 (11a) O H HO O H OH2 2 2 2+ + (11b)

PAGE 29

14 2 2O H OH OH + (11c) 2 2 2 2 2O O H HO HO + + (11d) O H O OH O H HO2 2 2 2 2+ + + (11e) O H O OH HO2 2 2+ + + (11f) This treatment has bee proven effective in oxidizin g organic compounds in both water and wastewater (Kang et al 1997, Crittenden e t al 1999, Lopez, 2003) and has not been evaluated to a great extent for its treatment of inorganics. Particles in Groundwater Particles in groundwater are a concern because they may shelter microorganisms from inactivation by disinfectants, provide a sorbe nt site for pesticides, synthetic organic chemicals, and heavy metals (USEPA, 1999). They ar e also of concern because they prevent treated water from being aesthetically plea sing to consumers by giving the water a cloudy appearance. These particles can range in size from below one micron to over 20 microns (McCarthy, 1993). There are many causes for the prese nce of these particles in groundwater including water quality within the aqui fer and chemical changes due to treatment. Common methods used for particle charac terization include turbidity measurements, particle counting, and scanning elect ron microscopy. The following sections outline the types of particles in groundwa ter, their sources, and characterization methods.

PAGE 30

15 Types of Particles Found in Groundwater The organic particles in groundwater consist of mic roorganisms including viruses and bacteria, natural organic matter (NOM) or synth etic organics which (McCarthy, 1993) may give water an unpleasant color, taste, an d/or odor. When treated by chlorine, NOM may react to form to disinfection-by-products, including trihalomethanes and haloacetic acids, which are regulated under the Saf e Drinking Water Act. One approach to reduce the production of disinfection byproducts is to reduce the amount of chlorine that is used for treatment by using other oxidants or by adding ammonia to the water to form chloramines (AWWA, 1999). The inorganic parti cles may consist of mineral precipitates such as iron, calcium, and manganese, rock and mineral fragments, metal sulfides, elemental sulfur, silts and clays (McCarthy, 1993). Causes of Particle Presence in Groundwater There are several contributing factors to particle formation in groundwater as are listed in Table 4. Table 4: Factors that influence particle formation Factor Impact pH Changes Increase in pH results in precipitation of minerals while a decrease in pH results in dissolution of minerals Redox Potential Increases or decreases in redox potential affect th e solubility of nutrients in water, especially minerals Partial Pressure Changes in partial pressures of gases such as cause s a disruption in the equilibrium status of those systems and may result in precipitation or dissolution depending on which pathway reestablishe s equilibrium conditions.

PAGE 31

16 Typically, the mineral content of precipitates in g roundwater depends on local geohydrology and includes iron and manganese oxides calcium carbonates, or metal sulfides. These precipitates may also be formed by microbiological activity or anthropogenic influences (McCarthy, 1993). Particles can also be generated through water treat ment. The introduction of oxidants and disinfectants, such as chlorine and/or chloramines modifies water chemistry and may promote the precipitation of minerals and o rganic materials. Groundwater treatments such as forced-draft aeration (Duranceau et al. 2002) and softening have the potential to generate particles. Filtration and me mbrane technologies selectively remove particles. Particle Characterization Methods There are many methods used to characterize particl es in groundwater. The methods used in this project are described in the following section. The methods are turbidity measurements, particle count with size distribution and scanning election microscopy (SEM) in conjunction with energy dispersive spectro scopy (EDS).

PAGE 32

17 Turbidity Turbidity is a measurement of the relative clarity of water. It is not to be confused with color, however, the particles that cause turbidity may affect the color of the water and the color of the water may interfere with the measureme nt of turbidity. Turbidity is quantified using principles of nephelometry and ope rates by passing a beam of light at a wavelength of 450 nm through a sample of water. Th e intensity of the scattered light is measured by a photoelectric cell perpendicular to t he light source. The current standard units of measurement are nephelometric turbidity un its (NTUs) and are derived based on the light scattering signal from different concentr ations of a colloidal formazin suspension. Turbidity is a primary drinking water contaminant under the Safe Drinking Water Act (SWDA). The maximum contaminant level (M CL) for turbidity in surface water is 0.3 NTU, but there is no limit currently s et for groundwater. The primary downfall for turbidity measurement is that it gives no indication as to the amount of particles in a water source or the size of those pa rticles. There is no direct correlation between particle size, light scattering, and partic le mass. There are also inconsistencies in turbidity measurements due to variations in turb idimeter models, calibration techniques, and standard operating procedures.

PAGE 33

18 Particle Count and Size Distribution Particle count is an important measurement for the assessment of water quality and treatment efficiency (AWWARF, 1995). This meas urement allows for total particle count as well as obtaining a size distribution. Th is measurement correlates to turbidity measurements except in cases of very low turbidity samples (AWWARF, 1995). In a study performed by Borrill and McKean, it was found that there was a correlation between particle count and turbidity in a high turb idity water with a R2 value of 0.87, but a poor correlation between the two measurements for filtered water with a R2 value of only 0.40 (AWWARF, 1995). Particle counting has mo stly been associated with evaluating filter performance in water treatment pl ants (AWWARF, 1995). Scanning Electron Microscopy (SEM) Scanning electron microscopy (SEM) allows for resea rch into the structure and properties of particles that are too small to be se en with a normal microscope. This technology provides detailed 3-dimensional images o f microscopic particles. The SEM works by bombarding a sample with a concentrated be am of high energy electrons which excites the sample and creates an image. Therefore by studying the interaction of the disinfectants with the water and evaluating the par ticles produced, conclusions can be drawn about the impact that disinfection has on gro und water quality.

PAGE 34

19 Article 1: Potential for Colloidal Particle Formati on Resulting from Groundwater Disinfection Abstract Typically, groundwater treatment systems are target ed at removal of dissolved minerals (e.g. iron, manganese, calcium, magnesium) and/or dissolved gases (carbon dioxide, hydrogen sulfide) followed by disinfection In other cases, disinfection may be the sole treatment step. The upcoming groundwater rule (GWR) will introduce more detailed requirements for disinfection and monitori ng of water systems served by groundwater. In many groundwater treatment systems disinfection consists of in-line introduction of disinfectant chemicals such as ozon e, chlorine, or chlorine and ammonia. The effectiveness of disinfection is assessed throu gh distribution system monitoring in accordance with the Total Coliform Rule (TCR). Lim ited information is available on secondary reactions that occur downstream of chemic al addition. Water quality impacts associated with disinfection are evaluated in this paper with an emphasis on the potential for formation of colloidal particles due to oxidati on, precipitation, or biological reactions. Pilot-scale disinfection of a groundwater source in west-central Florida was conducted using chlorine, chlorine-ammonia, UV, UV-chlorine, and UV-chlorine-ammonia at

PAGE 35

20 ambient (7.0-7.5) and elevated (8.2-8.3) pH. Under ambient pH conditions, the use of UV as a primary disinfectant followed by chloramina tion produced the highest concentration of particulate material. However, un der elevated pH conditions, higher particle concentrations were associated with the us e of chlorine alone or in combination with ammonia. In general, submicron colloidal part icles (< 0.2 microns) consisting of organic microspheres with trace amounts of iron and sulfur were generated downstream of chemical addition. Key words— chlorine, UV irradiation, sulfur, groundwater rule, 4-log inactivation Introduction The groundwater rule (GWR) will require all groundw ater treatment systems to be capable of achieving 4-log inactivation or remov al of viruses and the maintenance of a disinfectant residual throughout the distribution s ystem (GWR, 2000). Design of disinfection systems requires that the product of t he residual disinfectant concentration (C) and contact time (T), or CT value, is appropria te for 4-log virus inactivation based on the disinfectant chemical, pH, and temperature. Th e effectiveness of disinfection is assessed through monitoring of total coliforms and disinfectant residuals in the distribution system, in accordance with the Total C oliform Rule (TCR). Chlorine is the most widely used disinfectant for g roundwater systems (Sincero, 2003) and, in most cases, it is added in either gas eous (Cl2) or liquid (NaOCl) form. The

PAGE 36

21 addition of chlorine to water can result in a chang e in pH, depending on the form of chlorine, the dose, and the alkalinity. Gaseous ch lorine can result in a pH decrease, whereas the use of sodium hypochlorite can increase the pH as shown in equations (1) and (2). Cl2 + H2O H+ + Cl+ HOCl (1) NaOCl + H2O Na+ + HOCl + OH(2) The extent of pH change due to the addition of eith er form of chlorine is controlled by the concentrations of alkalinity and dissolved carbon dioxide and the extent of treatment prior to chlorination. Groundwater ty pically contains dissolved carbon dioxide that can react with the hydroxide released during the addition of sodium hypochlorite, resulting in an increase in alkalinit y. The pH affects the degree of ionization of hypochlorous acid as shown in equatio n (3) HOCl H+ + OClpK = 7.5 (3) Because the oxidation potential of hypochlorous aci d and hypochlorite are different, 1.611 and 0.81, respectively (Lide, 1990 ), the pH impacts the net oxidation potential available for disinfection. Over the past decade, chlorination practices have s hifted due to concerns about water system security and the hazards of on-site st orage of gaseous chlorine, many

PAGE 37

22 utilities have switched from the use of gaseous chl orine to liquid chlorine. In addition, more stringent limits for disinfection byproducts ( DBPs) have prompted utilities to convert from the traditional practice of maintainin g a free chlorine residual to the use of a primary disinfectant followed by chloramination for maintenance of a residual in the distribution system. In addition to chlorine, prim ary disinfectants include ozone or UV. The addition of ammonia to form chloramines can als o impact the pH. Chlorine and other disinfection chemicals also reac t with reduced minerals and organics in water. The dose of disinfectant chemic al needed to meet the CT requirements includes the dose required to satisfy oxidation rea ctions and the dose required to maintain a disinfectant residual between 0.2 and 5 mg/L. Co nstituents in groundwater that react with disinfection chemicals include hydrogen sulfid e, reduced iron, and reduced manganese. A summary of the chlorine demand associ ated with these oxidation reactions is given in Table 5. The chlorination reactions ca n result in a net increase or decrease in pH, depending on the chemical dose and alkalinity. In addition, the solubility of the reaction products is impacted by pH. Table 5: Chlorine oxidation of iron, manganese, and hydrogen sulfide Oxidation Reaction Chlorine requirement, mg/mg Fe+2 + HOCl Fe+3 + Cl+ OH0.94 Mn+2 + Cl2 + 2H2O MnO2(s) + 2Cl+ H+ 1.27 H2S + 4HOCl SO4 -2 + Cl+ 4 H+ 8.23 H2S + HOCl So + Cl+ OH2.06

PAGE 38

23 It has been widely reported that particulate matter can interfere with disinfection effectiveness in drinking water systems by shieldin g pathogens from the action of disinfectants, and may provide surface area for the accumulation of microbial substrates and biofilms (USEPA, 1999). Thus the formation of particulates through oxidation reactions may impact disinfection effectiveness. Typically, the concentration of particulate matter in water systems is assessed through monitoring of turbidity. In surface water treatment systems, turbidity is used as a measure of the effectiveness of filtration. The Su rface Water Treatment Rule (SWTR) requires that treated water turbidity must be below 0.3 NTU in at least 95 percent of the samples measured per month and must never exceed 1 NTU (EPA Guidance Manual, 1999). However, limited information is available a bout turbidity levels in groundwater and the potential role of particulate matter in dis infection systems. The regulations that apply to groundwater treatment are outlined in Tabl e 6.

PAGE 39

Table 6: Comparison of regulations pertaining to pa rticles and disinfection rules in groundwater and s urface water treatment Regulations Existing or Future Implementation Date Description Monitored at Treatment Plant or Distribution System Total Coliform Rule (TCR) Existing (1989), but under revision. TCR monitors for the presence of total and fecal coliform. Presence indicates that other harmful bacteria may be present. The total number and location of samples is based on the population served. Distribution System Lead & Copper Rule (LCR) Revised in 2000 LCR sets maximum contaminant levels (MCLs) for lead (0.015mg/L) and copper (1.3 mg/L) based on the 90th percentile level of tap water samples. Need to explain how samples are collected Distribution System Long Term 2 Enhanced Surface Water Treatment Rule July 2005 Requires monthly monitoring for large sys tems (>10,000 people) of Cryptosporidium for two years to characterize water quality. Then depending on the concentration, methods of removal in addition to conventional treatment and filtering will have to be implemented. Small systems (< 10,000 people), monitor E.Coli. Treatment Plant stage 2 disinfectants/disinfection byproducts rule Regulates the disinfectant concentration and disinfection byproduct amounts in treated water. Large and medium systems must comply with 0.0080/0.060mg/L TTHM/HAA5 LRAA six years after promulgation and after ten years for small systems. Plant and distribution system 24

PAGE 40

25 The purpose of this paper is to evaluate the potent ial for particulate material to form in groundwater as a result of disinfection. T he objectives are: 1. Identify sources and characteristics of groundwater particles 2. Examine particle characteristics in a Floridan grou ndwater. 3. Evaluate the impact of disinfection treatment on pa rticle characteristics at ambient and elevated pH levels. Background Sources of particles in groundwater include mineral s, microorganisms, and organic material. Water treatment technologies, su ch as those used for oxidation, disinfection, and softening can act to modify the t ypes and characteristics of groundwater particles by oxidation, precipitation reactions or by liquid-solid separation. Organic particles may consist of microorganisms such as vir uses, bacteria, protozoa, and algae, natural organic matter (NOM), or synthetic organics due to localized contamination (need reference here). Inorganic particles in groundwate r consist of mineral precipitates such as iron, calcium, and manganese, rock and mineral f ragments, metal sulfides, elemental sulfur, silts, and/or clays (McCarthy, 1993). The dominant cations in water inclu de calcium, magnesium, iron, and manganese. These con stituents can precipitate with carbonates, sulfates, sulfides, phosphates, hydroxi des, and fluorides. A summary of the solubility products for mineral precipitates that m ay form in groundwater is given in

PAGE 41

26 Table 7 (Lide, 1990).In general, higher values of s olubility products reflect a higher degree of solubility. Table 7: Potential forms of mineral precipitates in groundwater and their corresponding solubility products at 25C Cations Anions Calcium, Ca2+ Ferrous Iron, Fe2+ Ferric Iron, Fe3+ Magnesium, Mg2+ Manganese, Mn2+ Carbonate, CO3 2-4.96*10-9 3.07*10-11 6.82*10-6 2.24*10-11 Fluoride, F1.46*10-10 2.36*10-6 7.42*10-11 Hydroxide, OH4.68*10-6 4.87*10-17 2.64*10-39 5.61*10-12 2.06*10-13 Sulfate, SO4 27.10*10-5 Sulfides, S21.59*10-19 4.65*10-14 Phosphates, PO4 32.07*10-33 9.92*10-29 9.92*10-29 9.86*10-25 The major factors that contribute to the presence o f particles in groundwater are pH, redox potential, and partial pressure fluctuations (McCarthy, 1993). Particles may also be generated through water treat ment. The introduction of oxidants and disinfectants, such as chlorine and/or chloramines can affect the chemistry

PAGE 42

27 of water and may promote the precipitation of miner als and organic materials. Groundwater treatments such as forced-draft aeratio n (Duranceau et al. 2002) and softening have the potential to generate particles. Filtration and membrane technologies selectively remove particles. Most of the groundwa ter treatment plants that do not use aeration or softening do not have mechanisms in pla ce for particle removal. The possible generation of other treatments such as disinfection producing particles that may need to be removed is rarely given consideration. As such, this paper was produced to show that there is a potential for particle generation from d isinfection treatment. Methods This project consisted of bench-scale and pilot-sca le testing of groundwater derived from wells in west-central Florida. The ut ility withdraws two million gallons per day (MGD) from the Floridan aquifer through eight w ells distributed through their service area. Prior to 2005, water was treated at each well site using in-line addition of chlorine and a polyphosphate corrosion inhibitor, f ollowed by a 10 minute reaction time in a hydropneumatic tank. Under typical operating conditions, the pumps at each treatment system do not operate continuously, but c ycle on and off in response to pressure demands within the system. The ability to store treated water within the existing system is limited to hydropneumatic tanks at the we ll sites with a combined effective volume of 27,500 gallons and a 500,00 gallon ground storage tank that provides supplemental storage. The utility is in the proces s of modifying their treatment to

PAGE 43

28 provide chlorine as a primary disinfectant, followe d by the addition of ammonia to form chloramines for secondary disinfection. The bench-scale tests were conducted to gain inform ation about the optimum chlorine dose and pH levels, and changes in water q uality. For the bench-scale tests 1 or 2 liter reactors were used. Samples were collected using a special sampling device that minimized exposure to air. The impact of disinfection on particle concentratio ns and characteristics was evaluated. The disinfectants tested included chlor ine, chloramine, UV, UV-chlorine, or UV-chloramine were evaluated using a 1 gpm (3.78 L/ min) pilot plant unit. The treatments were tested at ambient pH and elevated p H. An elevated pH of 8.2-8.3 was used to simulate treatment plants that control corr osion using pH and alkalinity control. Talk Water was pumped from one of the wells into a 1 gallon per minute (3.78 L/min) pilot plant. The detention times for relevant segm ents of the pilot plant are summarized in Table 8. The schematic for the pilot plant is s hown in Figure 3. Table 8: Detention times of reactors From To Detention Time (min) Inlet Outlet 22 pH Injection UV Unit 2 UV Unit Chlorine Injection 5 Chlorine Injection Ammonia Injection 3 Ammonia Injection Outlet 10

PAGE 44

Figure 3: Schematic of pilot plant 29

PAGE 45

30 A 10.5% sodium hypochlorite (liquid chlorine) solut ion was dosed to the system within the range of 21-25 mg/L. For chloram ine experiments, a 25% ammonium hydroxide (ammonia) solution was dosed to the syste m within the range of 0.1 to 1 mg/L based on a 1:4 ratio of ammonia to chlorine residua l. The UV intensity ranged from 10 to 20 mWsec/cm2. Water quality tests were performed on the bench-sca le and pilot-scale tests. The procedures for each test were based on Standard Met hods for the Examination of Water and Watewater, 20th Edition (1998). A list of the tests conducted is outlined in Table 9. Field analyses were conducted at the well site and laboratory analyses were conducted in the USF environmental laboratory.

PAGE 46

Table 9: Summary of analytical parameters tested Test Field or Lab Standard Method, 20th Editionnumber Instrument Used Detection Limit/Sensitivity Storage/ Preservation Alkalinity, mg/L CaCO3 Field 2320 B. Titration Method Bromocresol green/methyl red 20 mg/L CaCO3 N/A Color(true & apparent), mg/L PtCo Field 2120 C Spectrometric Method Hach DR/2400 Portable Spectrophotometer 5 PtCo Units N/A Conductivity, S/cm Field 2510 B Laboratory Method Hach sension 156 Portable Multiparameter Meter 20 S/cm N/A ORP, mV Field ExStik pH and ORP Probe 999mV N/A pH Field 4500-H+ B. Electrometric Method Hach sension 156 Portable Multiparameter Meter 0.01 pH units N/A Solids (total, suspended, and dissolved) (0.2m filter used) Lab 2540 A-D. Solids N/A 10 mg/L Store at 4C and begin test within three days Sulfate, mg/L SO4 2Field 4500SO4 2E. Turbidimetric method Hach DR/2400 Portable Spectrophotometer 2 mg/L as SO4 2N/A Sulfide, mg/L S2Field 4500-S2 D Methylene blue method Hach DR/2400 Portable Spectrophotometer 0.1 mg/L as S2N/A 31

PAGE 47

Table 9: continued Temperature, C Field 2550 B. Laboratory Method. Hach sension 156 Portable Multiparameter Meter 0.01C N/A TOC, mg/L TOC Lab 5310 C. Persulfate-UV Method Sei vers 800 Portable Total Organic Carbon Analyzer 0.05 mg/L Acidified to pH=2 with sulfuric acid and analyze as soon as possible Turbidity, NTU Field 2130 B Nephelometric Turbidity Hach model 2100 AN Laboratory Turbidimeter 0.01 NTU 32

PAGE 48

33 Sample aliquots were also stored and preserved for Scanning Electron Microscopy(SEM) / Electron Dispersive Spectroscopy (EDS) analysis. 5 mL of 10% gluteraldehyde was added to 20 mL of sample to yiel d an overall gluteraldehyde concentration of 2%. Following gluteraldehyde pres ervation, particulate matter was concentrated by filtration though a 47 mm nylon fil ter with a pore size of 0.1 m. The filters were rinsed 3 times with deionized water to remove the salts and then dehydrated using a graded series of ethanol (30%, 50%, 70%, 95 %, and 100%). Samples were submerged in each ethanol solution for a minimum of two sequential 10 minute periods. After the final soak, the ethanol was decanted off and the samples were dried overnight at 50C. In order to minimize field sample contamination, th e samples were collected using a special sampling device that prevented expo sure to the atmosphere for field tests. The samples were then analyzed immediately. The Er lenmeyer flasks used to hold the samples in the field were rinsed thoroughly with Na nopureTM water twice, then rinsed with sample three times. 10-50mL disposable serolo gical pipettes were used and rinsed with NanopureTM water after each use and discarded after each expe riment. The samples that were transported to the lab were collected in black or foil-covered BOD bottles to prevent photoreactions. The bottles and stoppers w ere pre-cleaned by soaking in 1% nitric acid overnight, then rinsed with NanopureTM water and allowed to air dry for 24 hours. The samples for SEM were preserved immediat ely to prevent bacterial growth.

PAGE 49

34 Results and Discussion The goal of this study was to identify the sources of particles in this groundwater source, and to characterize the particl es found in both the raw and treated water. Therefore this section first discusses the source water quality and the sources of potential particle formation, followed by the chara cterization of particles formed from treatment using turbidity analysis, solids data ana lysis, particle count, and SEM analysis. Source water characteristics are summarized in Tabl e 10. Sulfide and TOC are the major contributors to oxidant demand in gro undwater. Table 10: Summary of untreated water quality data f rom a groundwater source in west-central Florida (2004-2005 monitoring data) Parameter Range Average Standard Deviation n pH 7.22 7.77 7.46 0.10 46 Temperature, C 25 – 31 26 1.5 23 Conductivity S/cm 479 – 661 529 36 41 Turbidity, NTU 0.1 5.1 0.7 1.1 44 Anions Alkalinity, mg/L CaCO3 130-240 199 19 32 Sulfate, mg/L SO4 211 – 43 27 6 25 Sulfide, mg/L S20.8 3.4 2.3 0.5 47 Chloride, mg/L Cl21 – 26 23 4 2 Cations Calcium, mg/L Ca2+ 80.8 116.3 92.3 16.4 6 Magnesium, mg/L Mg2+ 3.78 – 6.95 5.05 1.34 6 Ferrous Iron, mg/L Fe2+ <0.01-0.47 0.10 0.12 21 TOC, mg/L C 2.6-3.5 3.1 0.31 9 True Color mg/L PtCo 3 12 7 3 6

PAGE 50

35 From the parameters shown in Table 7, sulfide was o f most interest because of its variability. Therefore, figure 4 shows the relatio nship between turbidity and sulfide. An inverse relationship was detected. When the sulfid e levels increased, turbidity decreased. However, the relationship was not linear (r2 value= 0.27) or exponential (r2 =0.38). The variability of turbidity in untreated groundwater i s affected by changes in sulfide levels. It is clearly seen that an increase in sulfide leve ls result in a decrease in turbidity. 0 1 2 3 1.522.533.5 Sulfide, mg/LTurbidity, NTU Figure 4: Response of turbidity to sulfide levels i n well 9 From Table 10, the major constituents that will con tribute to mineral formation are calcium, magnesium, carbonate, sulfate, sulfide and chloride. Based on the Ksp values given in Table 7, the species that are most likely to form are calcium carbonate, magnesium carbonate, and magnesium hydroxide. The effects of treatment on all of these constituents are shown in Table 11.

PAGE 51

36 Table 11: Affect of disinfection treatment on water quality parameters at pH 8.2 Treatment Parameter Raw Water Chlorine Only ChlorineAmmonia UV Only UVChlorine UV-ChlorineAmmonia Alkalinity, mg/L CaCO3 195 225 235 225 225 240 Sulfide, S22.49 0 0 1.12 0 0 Sulfate, SO4 236.6 37 36.1 36.9 37.2 37.8 Calcium, m g/L Ca2+ 59 54 51 61 57 57 Magnesium, mg/L Mg2+ 7.4 7.2 7.3 7.2 7.2 7.3 TOC, mg/L C 3.0 2.7 2.8 2.7 2.7 2.7 Chlorine Demand, mg/L Cl2 13.9 13.6 17.2 11.0 The sulfide in the water was oxidized to a combinat ion of sulfur and sulfate. The dissolved calcium and magnesium decreased with trea tment, which indicates mineral precipitation. There was also a decrease in solubl e TOC, which is an indication of organic particle precipitation. Although the decre ase was slight, the fact that only about 40 percent of the mass of the organic particles is comprised of carbon, the total mass of organics that precipitates out may be significant. At ambient pH, the addition of the disinfectants ca uses the turbidity levels to increase as shown in figure 5. All treatments gene rated turbidity levels above 1 NTU at ambient pH. The turbidity increases in chlorine an d chloramine were moderate with increases of approximately 4 and 2 NTUs respectivel y. However, when the experiments were conducted with UV, a significant spike in turb idity was seen. Combining UV with

PAGE 52

37 chlorine or chloramine generates greater turbidity levels than UV only at ambient pH. However, when the pH is elevated, the reverse is se en, in that the turbidity generated due to UV disinfection was minimal whereas the turbidit y generated by chlorine and chloramine treatments was the highest. The UV-chlo rine and UV-chloramine produced turbidity levels between those treatments. All tre atments with the exception of UV only at an elevated pH of 8.2 showed turbidity levels ab ove 0.3 NTU, which is the standard for surface water which is outlined in the Surface Wate r Treatment Rule.. 0 2 4 6 8 10 12 14 16 18 20 NaOCl OnlyNH2Cl OnlyUV OnlyUV/NaOClUV/NH2ClTurbidity Formed, NTU ambient pH elevated pH Figure 5: Turbidity formed as a result of disinfect ion treatment The weight of the total solids was another variable that was affected by the addition of disinfectants to the water (Figure 6). The treatments that included chlorine showed roughly the same increase in mass of total s olids of approximately 20% from that in raw water, but the UV treatment showed a slight decrease. However, taking into

PAGE 53

38 account the errors associated with the test, it is justified to say that there was relatively no change in total solids associated with UV. Elevati ng the pH slightly decreased the mass of total solids produced by the chloramine only and UV-chloramine treatments, and had the reverse affect on chlorine and UV-chlorine. Ad ding disinfectants to the water had an interesting affect on suspended particles. For all treatments besides chloramine only and UV-chloramine, the change in suspended solids was n egative. This is significant because it indicates that the particles generated through t reatment are smaller than the filter pore size used to obtain the results which was 0.2m. T herefore, if a water treatment plant wanted to filter this water to remove the particles it would have to be a filter that would allow them to capture particles smaller that 0.2m. -5 0 5 10 15 20 25 30 NaO C l O nl y N H2Cl Onl y U V Onl y U V /N a OCl UV/NH 2Cl % Change in Mass for Total Solids-70 -60 -50 -40 -30 -20 -10 0 10 20 30 % Change in Mass for Suspended Solids Total Solids at ambient pH Total Solids at elevated pH Suspended Solids at ambient pH Suspended Solids at elevated pH Figure 6: Comparison of % total and suspended solid s from disinfection treatments The total particle count was measured to see how tr eatment affects the number of particles and how the number of particles is affect ed by changes in pH. Table 12 outlines

PAGE 54

39 the total particle count for the treatments and the impact that pH has on them. The average raw water particle count is 4636/mL with a standard deviation of 2979/mL. Disinfection addition greatly raised the total part icle count at ambient pH. The greatest increase on particle count was seen by chloramine o nly and UV-chloramine treatments which parallels the results seen from the total sol ids data. Elevating pH causes a significant change in the particle count number for UV-Chlorine in that it decreased by 113%. This is in direct contrast with the total so lids data which showed a mass increase of almost 20%. The remaining treatments also showe d this inverse relationship between change in mass of total solids and change in partic le count. Table 12: Affect of pH on total particle count Treatment Count at Ambient pH, #/mL Count at Raised pH, #/mL Particle Count (AmbientRaised), #/mL % Change in Particle Count, % Chlorine Only 3.5E+04 4.9E+04 -1.4E+04 -40 Chloramine Only 5.3E+04 3.6E+04 1.6E+04 32 UV Only 1.5E+04 1.7E+04 -0.2E+04 -13 UV-Chlorine 1.6E+04 3.4E+4 -1.8+04 -113 UV-Chloramine 5.0E+04 3.6E+04 1.3E+04 26 The addition of disinfectants did not seem to impac t the size distribution of the particles above 1 micron. However, it was establis hed from the suspended solids data that the majority of particles that are generated b y disinfection addition are less that 1 micron in size. This observation was further corro borated by the SEM analysis. The particles found in the analysis of the untreated gr oundwater ranged from 1 micron to over

PAGE 55

40 15 microns as shown in Figure 7. The particles wer e mostly microorganisms, with trace amounts of inorganic matter such as iron and sulfur Figure 7: Scanning electron micrographs of particle s in untreated groundwater. The approximate size of the particles are a) 2 micr ons b) 3 microns c) 3 microns and d) 15 microns After the addition of disinfectants to the water, t he size range of the particles changed. The majority of the particles were less t han 1 micron as shown in figure 8. The EDS analysis still showed that the major elements w ithin these particles were carbon and oxygen, meaning that they are organic in nature. 5 m 1 m 1 m 1 m

PAGE 56

41 Figure 8: Scanning electron micrographs of particle s in treated groundwater The SEM micrographs also highlights one of the issu es associated with particles in water. Figure 9 clearly shows microorganisms th at are attached to particulate matter. The microorganisms shown are possibly using the par ticles as shields from disinfection, a food source, or as a substance to grow on. Figure 9: Scanning electron micrographs of microorg anisms in groundwater that are attached to particulate matter Conclusions The experimental studies described in this paper su ggest the following conclusions with respect to the particles found in untreated groundwater and the effect that disinfection using chlorine, chloramine, and/o r UV has on them. 500 n m 1 m 1 m 5 m

PAGE 57

42 1. The sources of particles in treated groundwater inc lude mineral precipitates of carbonates, calcium, and magnesium. From the SEM analysis, the particles were composed of mostly car bon and oxygen, suggesting that they are mostly organics. 2. The particles found in the untreated water ranged f rom 1 micron to over 15 microns, while the particles produced from treat ment were smaller than 1 micron. 3. There is a need for a mechanism to be put into plac e that would remove the particles generated through treatment before th e water is sent out to the distribution because of the high turbidity levels s een by all treatment except UV Only at elevated pH. These turbidity lev els exceed the 0.3 NTU turbidity limit set by the Surface Water Treatm ent Rule. Acknowledgements This project was funded by Aloha Utilities as part of a larger project on treatment alternatives. Jack Burke, Mike McDonald, and Charl ie Painter assisted in the construction of pilot plant, start-up and operation Salah Albustami and Camilo Romero assisted with field and laboratory analyses. Dave Edwards conducted the SEM/EDS analyses.

PAGE 58

43 Article 2: A Pilot Study Used to Evaluate In-Pipe C ontrol of Hydrogen Sulfide for Well-head Treatment of Groundwater Abstract In many groundwater treatment systems, chlorine ser ves a dual role as an oxidant and as a disinfectant. The chlorine demand exerted by hydrogen sulfide ranges from 5 to 8 mg chlorine per mg hydrogen sulfide. In groundwa ter systems that contain dissolved organic carbon and hydrogen sulfide, the high chlor ine dosages can lead to the formation of disinfection byproducts. One approach to reduci ng the chlorine demand is developing a pre-treatment system to oxidize the hydrogen sulf ide prior to chlorination. This project was conducted to evaluate the use of alternative ox idants appropriate for well-head treatment of groundwater. Oxidants evaluated inclu ded hydrogen peroxide and photochemical oxidation using UV or hydrogen peroxi de coupled with UV. While each oxidant was capable of reducing the hydrogen sulfid e concentration, reaction rates and reaction products varied. To minimize the producti on of turbidity, it was necessary to optimize the pH within a fairly narrow window.

PAGE 59

44 Introduction The control of sulfides in groundwater is of import ance because its presence can cause odor and taste complaints, corrosion of pipes and other plumbing fixtures, and black-water problems in distribution systems (Levin e et. al, 2004). Currently, the Safe Drinking Water Act (SDWA) or any of its amendments do not specifically address hydrogen sulfide. However, sulfides are indirectly regulated through the secondary drinking water standard for taste and odor. The se condary contaminants and their limits in water are outlined in Table 13 (USEPA, 2005). Table 13: Secondary drinking water standards set fo r compounds that contribute to odor and taste problems Contaminant Secondary Maximum Contaminant Level Chloride 250 mg/L Copper 1 mg/L Foaming Agents 0.5 mg/L Iron 0.3 mg/L Manganese 0.05 mg/L pH 6.5 8.5 Sulfate 250 mg/L Threshold Odor Number (TON) 3 TON Total Dissolved Solids 500 mg/L Zinc 5 mg/L

PAGE 60

45 In 2003, the Florida Department of Environmental Pr otection implemented a new rule pertaining to hydrogen sulfide removal under C hapter 62-555.35(5) (FDEP, 2005). This rule was implemented to control copper pipe co rrosion and black water production which is caused by the interaction of sulfides with copper (FDEP, 2003). The rule calls for a minimum of one sample of raw water to be meas ured for total sulfides and action is recommended if the total sulfide level is above 0.3 mg/L. The treatment recommendations are outlined in Table 14. Some of the major drawbacks associated with this rule are the lack of guidelines for sampling f or sulfide testing, lack of the number of samples needed to categorize the sulfide level, and lack of a monitoring frequency. Table 14: Summary of FDEP treatment recommendations for control of total sulfide in new or altered wells (adapted from FDEP Chapter 62-555.315 (5)) pH range Total Sulfide concentration in untreated water, mg/L <7.2 7.2 >7.2 Treatment recommendations Maximum removal efficiency <0.3 X X X Chlorination >90% X X Conventional aeration 0.3 to 0.6 X Conventional aeration with pH adjustment ~40-50% X X Forced draft aeration 0.6 to 3 X Forced draft aeration with pH adjustment ~90% >3.0 X X X Packed tower aeration with pH adjustment >90% Typically, for small water treatment systems, hydro gen sulfide is controlled through in-pipe treatment using chlorination. Aera tion is also used in many treatment

PAGE 61

46 facilities, but that also requires disinfection dow nstream to comply with disinfection regulations. The objective of this study is to eva luate the efficacy of using alternative oxidants for in-pipe oxidation of hydrogen sulfide prior to chlorination. Hydrogen peroxide was used in this study because of past res earch on the effectiveness of its use to control hydrogen sulfide levels in wastewater (Cade na, 1988, Tomar, 1994, Hoffman, 1977) and groundwater (Dohnalek, 1983). This paper is based on a case study done in west-central Florida. Background This section covers sulfide chemistry in groundwate r. Also discussed are treatment alternatives for its control with the emp hasis on oxidation treatments. Sulfide in Groundwater Sulfur exists in a nine oxidation states in water a nd can transition from one state to the next depending on localized chemical and bio logical reactions. Sulfide is formed in water through the action of sulfur reducing bact eria decomposing organic matter (Dohnalek, 1983) or by the desulfuration of organic compounds. Sulfides in water are undesirable because of their “rotten egg” odor and their corrosivity properties (Dohnalek, 1983). Total sulfides refer to dissolved hydrogen sulfide (H2S), ionized sulfide (HSand S2-) and acid-soluble metallic sulfides, and polysulfi des. The equilibrium equations for

PAGE 62

47 the three sulfide species are outlined in equations 1 and 2 and illustrated in Figure 10 with respect to pH. Various values have been reported f or the second equilibrium constant at 25C. A summary of values is given in Table 15. + -+ H HS S H2 ( ) ( ) () S H H HS K2 7 110+ -= = at C T20 = (1) + -+ H S HS2 ( ) ( ) + -= HS H S K2 2 at C T20 = (2) Table 15: Values of K2 obtained from various sources Source Benjamin, 2002 Garrels, et.al, 1965 Sillen, et. al 1964 Knox, 1906 Maronny, 1959 Value 10-12.92 10-14 10-17.1 10-14.92 10-13.78 0 20 40 60 80 100 02468101214 pHDistribution of Reduced S, %H2S HSS2pH Range of Source Water Figure 10: Illustration of sulfide equilibrium in t erms of pH

PAGE 63

48 Treatment Alternatives for the Control of Hydrogen Sulfide In addition to the treatment methods outlined in Ta ble 14, it is worthwhile to consider alternative approaches for control of hydr ogen sulfide that might be appropriate for small water systems such as anion exchange. Ox idation treatments are discussed below. Oxidation The addition of oxidants such as chlorine, hydrogen peroxide or ozone to groundwater serves to increase its oxidation potent ial. By manipulating the pH and the extent of the increase of oxidation potential which is controlled by chemical oxidant addition, the end products of sulfur oxidation can be controlled. This is illustrated in Figure 11. Theoretically, at a pH below 7, the pro duct formed from the oxidation of sulfide is either elemental sulfur or sulfate, depe nding on the oxidant’s affect on the overall potential and at a pH above 7 only sulfate is formed, regardless of the oxidant used.

PAGE 64

49 -10 -5 0 5 10 15 20 246810 pHpEH2S SO4 -2HS-SH2O O2H2 Oxidantaddition pH Control Oxidantaddition Figure 11: pE-pH equilibrium diagram for thermodyna mically stable sulfur species (Thermodynamic constants from Stumm and Morgan 1999 ) Hydrogen Peroxide Oxidation of Hydrogen Sulfide Hydrogen peroxide is a powerful oxidant with an oxi dation potential of -1.76V (Dohnalek, 1983). Cadena et. al states that sulfat e is the major product of peroxidesulfide oxidation over a pH of 7.5. 0 2 2 2 8 1 2 S O H H O H HS + + ++ pH < 7.5 (3)

PAGE 65

50 + -+ + + H O H SO O H HS2 2 4 2 24 4 pH > 7.5 (4) Only a few other oxidizers exceed the power of pero xide, such as elemental fluorine, ozone, and peroxodisulfate (Dohnalek, 198 8), and advanced oxidation technologies that generate hydroxyl radicals. Seve ral benefits that are associated with using hydrogen peroxide are that it breaks down int o oxygen and water, it does not contribute to disinfection-by-products, and it is n either toxic nor corrosive (Dohnalek, 1988). The kinetics for hydrogen peroxide oxidatio n of sulfide depends on dose, pH and temperature. Hydrogen-Peroxide/UV Advanced Oxidation Process Hydrogen peroxide in conjunction with UV irradiatio n is an advanced oxidation process that is gaining ground as an alternative to traditional treatment methods such as chlorination. The UV reacts with hydrogen peroxide to form hydroxyl radicals which are more powerful than any other oxidant used for hydro gen sulfide oxidation. Glaze et. al. gave the following reactions as a proposed pathway that may be used for this process (equations 5a-5f). OH hv O H + 22 2 (5a) O H HO O H OH2 2 2 2+ + (5b) 2 2O H OH OH + (5c)

PAGE 66

51 2 2 2 2 2O O H HO HO + + (5d) O H O OH O H HO2 2 2 2 2+ + + (5e) O H O OH HO2 2 2+ + + (5f) This treatment has been proven effective in oxidizi ng organic compounds in both water and wastewater (Kang et al 1997, Crittenden e t al 1999, Lopez, 2003) and has not been evaluated for the removal of hydrogen sulfide. Therefore, there is a need for research into this topic, as it may provide a new o ption for sulfide control in groundwater treatment. Methods All water samples used in this project were obtaine d from a utility in west-central Florida that produces two million gallons per day ( MGD) from the Floridan aquifer. Treatment consists of in-pipe treatment at each of eight well sites using chlorination. Bench-scale and pilot-scale tests were used to eval uate the effectiveness of alternative treatment approaches for control of hydrogen sulfid e in groundwater before chlorination. Information on the experimental design and methodol ogies used in this study is given below.

PAGE 67

52 Experimental Design Bench-scale tests were completed at several wells t o evaluate the hydrogen peroxide reaction rates and obtain the correct chem ical dose and pH level. Pilot-scale tests were completed to evaluate the effectiveness of the hydrogen peroxide on sulfide removal in a flow-through system prior to chlorinat ion, and also to evaluate its effect on other water quality parameters. An outline of the oxidation tests conducted is given in Table 16. Table 16: Summary of bench-scale and pilot-scale te sts conducted Testing Goals Technology pH Optimum Chemical Dose Requirements Sulfide removal/ conversion Turbidity formation potential Chlorine demand Bench-scale Tests Hydrogen Peroxide Yes Yes Yes No Yes Hydrogen PeroxideChlorine Yes Yes Yes No Yes Pilot -Scale Tests Chlorine Yes Yes Yes Yes Yes Hydrogen peroxide Yes Yes Yes Yes Yes Hydrogen peroxide-UV Yes Yes Yes Yes Yes Hydrogen peroxidechlorine Yes Yes Yes Yes Yes Hydrogen peroxide-UVchlorine Yes Yes Yes Yes Yes

PAGE 68

53 Analytical Tests Analytical tests were performed on the bench-scale and pilot-scale tests. The procedures for each test were based on Standard Met hods for the Examination of Water and Wastewater, 20th Edition (1998). A list of the tests conducted is given in Table 17. Field analyses were conducted at the well site and laboratory analyses were conducted in the USF environmental laboratory. Hydrogen Peroxide Determination The method used for measuring hydrogen peroxide was derived from its reaction with titanium ions which forms a yellow colored com plex. This complex absorbs most strongly at 410nm and can be measured spectrophotom etrically to determine hydrogen peroxide concentrations in the ppm range. The reag ent for making hydrogen peroxide determinations is an acidic solution of titanium pr epared by adding 24 mL of titanium tetrachloride to 300 mL of 6M HCl. This reagent ne eds to be tightly capped and stored in a cool dark place. The interferences are strong al kaline samples, turbidity, reducing agents, and any substance that absorbs at 410 nm.

PAGE 69

Table 17: Summary of analytical parameters tested Test Field or Lab Standard Method, 20th Edition-number Instrument Used Detection Limit/ Sensitivity Storage/ Preservation Alkalinity, mg/L CaCO3 Field 2320 B. Titration Method Bromocresol green/methyl red 20 mg/L CaCO3 N/A Color(true & apparent), mg/L PtCo Field 2120 C Spectrometric Method Hach DR/2400 Portable Spectrophotometer 5 PtCo Units N/A Conductivity, S/cm Field 2510 B Laboratory Method Hach sension 156 Portable Multiparameter Meter 20 S/cm N/A ORP, mV Field ExStik pH and ORP Probe 999mV N/A pH Field 4500-H+ B. Electrometric Method Hach sension 156 Portable Multiparameter Meter 0.01 pH units N/A Sulfate, mg/L SO4 2Field 4500SO4 2E. Turbidimetric method Hach DR/2400 Portable Spectrophotometer 2 mg/L as SO4 2N/A Sulfide, mg/L S2Field 4500-S2 D Methylene blue method Hach DR/2400 Portable Spectrophotometer 0.1 mg/L as S2N/A Temperature, C Field 2550 B. Laboratory Method. Hach sension 156 Portable Multiparameter Meter 0.01C N/A TOC, mg/L TOC Lab 5310 C. Persulfate-UV Method Seivers 800 Portable Total Organic Carbon Analyzer 0.05 mg/L Acidified to pH=2 with sulfuric acid and analyze as soon as possible Turbidity, NTU Field 2130 B Nephelometric Turbidity Hach model 2100 AN Laboratory Turbidimeter 0.01 NTU 54

PAGE 70

55 Bench-Scale Tests The bench-scale tests were conducted to gain inform ation about the optimum hydrogen peroxide dose, optimum pH level, the react ions rates, and changes in water quality. For the bench-scale tests 1 or 2 liter ba tch reactors were used. Samples were collected using a special sampling device that mini mized hydrogen sulfide loss. Water entered at the bottom of the device and overflowed at the top. The samples were collected from a tube located midway on the device. This allowed for minimum gaseous exchange. A 3% hydrogen peroxide solution was dosed at concen trations of 1.5 to 18 mg/L. The sulfide levels were monitored at one minute int ervals 10 minutes. This allowed for the evaluation of the reaction kinetics and allowed for the determination of the reactor dimensions and detention times for the pilot plant. These experiments were conducted at pH levels within the range of 7.5 to 8.5 to determi ne the optimum pH for this treatment. Based on these experiments conducted, it was determ ined that a 0.5mg hydrogen peroxide per mg sulfide was the optimum ratio and t he optimum pH was 8.3. Pilot Plant Design From the results gathered from the bench-scale test s, a pilot-scale treatment unit was built. In-line chemical treatment of groundwat er was tested in a flow-through pilot

PAGE 71

56 plant consisting of approximately 40 meters of clea r schedule 40 PVC pipe (2 inch ID) with approximately 8 meters of inch ID connectors joining each section of pipe. Chemical injection ports containing in-line mixers were placed at intervals through the plant to allow for injection of different test chem icals. Tracer tests using either salt solutions or dyes we re conducted to evaluate the hydraulic conditions and the detention times for ea ch portion of the pilot plant. The sequence of chemical addition points, detention tim e of each segment of the pilot plant, and chemical dose ranges are summarized in Table 18 Table 18: Detention times of reactors From To Detention Time (min) Chemical Dose Range, mg/L Inlet Outlet 20 N/A pH Injection Hydrogen Peroxide Injection 1 N/A Hydrogen Peroxide Injection UV Unit 1 1.15-1.35 UV Unit Chlorine Injection 5 1.15-1.35 Chlorine Injection Outlet 13 21-25 The hydrogen peroxide dose was approximately 1.25 m g/L. This dosage was based on the optimum ratio of 0.5 mg of hydrogen pe roxide/mg sulfide that was derived from the bench-scale tests, using an average sulfid e level of 2.5 mg/L based on historical sulfide data for the well. The hydrogen peroxide c oncentration was tested photometrically using a titanium chloride method. A 10.5% sodium hypochlorite (liquid chlorine) solution was dosed to the system within t he range of 21-25 mg/L.

PAGE 72

57 Results and Discussion The source water characteristics are summarized in Table 19. From the table, it is seen that sulfide levels for the wells vary from 0. 8 to 3.4 mg/L. However, over 90% of the sulfide measurements above 2 mg/L were from wel l 9. Therefore, the majority of the bench-scale and pilot testing was done at well 9. Table 19: Summary of untreated water quality data f rom a groundwater source in west-central Florida (2004-2005 monitoring data) Parameter Range Average Standard Deviation Number of samples pH 7.22 7.77 7.46 0.10 46 Temperature, C 25 – 31 26 1.5 23 Conductivity S/cm 479 – 661 529 36 41 Turbidity, NTU 0.1 5.1 0.7 1.1 44 Anions Alkalinity, mg/L CaCO3 130-240 199 19 32 Sulfate, mg/L SO4 211 – 43 27 6 25 Sulfide, mg/L S20.8 3.4 2.3 0.5 47 Chloride, mg/L Cl21 – 26 23 4 2 Cations Calcium, mg/L Ca2+ 80.8 116.3 92.3 16.4 6 Magnesium, mg/L Mg2+ 3.78 – 6.95 5.05 1.34 6 Ferrous Iron, mg/L Fe2+ <0.01-0.47 0.10 0.12 21 TOC, mg/L C 2.6-3.5 3.1 0.31 9 True Color mg/L PtCo 3 12 7 3 6

PAGE 73

58 Bench-Scale Tests From the bench scale tests using a hydrogen peroxid e to hydrogen sulfide ratio of 0.5:1 at pH 8.2, it can be seen in figure 12 that a pproximately 70 to 85% of the sulfide was removed within the first six minutes of the rea ction for three wells. After that, the reaction plateaued and little change in sulfide lev el was noted. 0 1 2 3 02468 Time (min)Hydrogen sulfide, mg/L well 9 well 8 well 2 Figure 12: Hydrogen sulfide removal using a hydroge n peroxide to hydrogen sulfide ratio of 1:1 The initial rate of hydrogen sulfide removal could be modeled as a zero order reaction for the first two minutes. After two minutes, the rate of hydrogen sulfide removal was modeled as a pseudo first order reaction with a rat e constant of 0.05 min-1 (Levine, 2004).

PAGE 74

59 Pilot Scale Tests The pilot scale tests were conducted to evaluate th e effectiveness of using hydrogen peroxide as a pretreatment before chlorina tion. For these tests, two pH levels were used: ambient and elevated. The sulfide remov al amount and percentages are shown in figure 13. The results validated the resu lts from the bench scale tests in that better sulfide removal is achieved at a pH of 8.2. 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 PeroxideUVPeroxide-UVAvaerage Sulfide Removed, mg/L0 10 20 30 40 50 60 70% Sulfide Removed Ambient pH pH 8.2 % Removal Ambient pH % Removal pH 8.2 Figure 13: % Sulfide removal at ambient and elevate d pH levels Based on the stoichiometric equation for the reacti on between hydrogen peroxide and hydrogen sulfide, + -+ + + H O H SO O H HS2 2 4 2 24 4 pH > 8.0

PAGE 75

60 for each mole of sulfide consumed, a mole of sulfat e is produced. Therefore, from a theoretical point of view, the change in the amount of sulfate can be evaluated. For ambient pH, 0.59 mg of sulfide was consumed usi ng hydrogen peroxide only. Therefore, -= mmolHS mmolS mmolHS mgS mmolS mgS 018 .0 32 1 59.02 2 2 2was consumed. Therefore, 0.018mmol of sulfate or -= 2 4 2 4 2 4 2 477.1 96 018 .0 mgSO mmolSO mgSO mmolSO should have been produced. The sulfate measurement s were taken using a spectrophotometer with limited sensitivity. The te st has an error associated with it of 2mg/L. The measured sulfate formed was 0.5 mg/L. Therefore, the theoretical amount of sulfur that was produced can be calculated from the stoichiometric equation, 0 2 2 2 8 1 2 S O H H O H HS + + ++ which is only supposed to occur at pH levels below 8. The amount of sulfide that produced the e lemental sulfur is -= = mmolHS mmolSO mmolHS mgSO mmolSO mgSO mgSO mgSO mgSO 01323 .0 1 96 1 27.1 27.1 5.0 77.12 4 2 4 2 4 2 4 2 4 2 4 2 4 For every mole of sulfide consumed, 1/8mole of elem ental sulfur is formed, therefore,

PAGE 76

61 0 0 0 0053 .0 32 8 1 01323 .0mgS mmolS mgS mmolHS mmolS mmolHS = -or 78.3 g of elemental sulfur is produced per liter of water. The element al sulfur predictions are outlined in Tables 20 and 21. Table 20: Prediction of elemental sulfur produced a t ambient pH Theoretical Sulfate Produced, mg/L SO4 2Actual Sulfate Produced, mg/L SO4 2Prediction of amount of elemental sulfur produced, mg/L Peroxide only 1.77 0.5 0.053 UV Only 3.36 6 -0.110 Peroxide-UV 3.36 1.5 0.078 Table 21: Prediction of elemental sulfur produced a t pH 8.2 Theoretical Sulfate Produced, mg/L SO4 2Actual Sulfate Produced, mg/L SO4 2Prediction of amount of elemental sulfur produced, mg/L Peroxide only 3.17 -0.5 0.153 UV Only 4.13 -1.5 0.234 Peroxide-UV 4.64 -2.7 0.306 When analyzing the solids data to see if this corre sponded to a rise in suspended solids, it was found that there wasn’t. However, t he error associated with the suspended solids test is 10 mg/L. The same problem is seen with turbidity. With the production of elemental sulfur, an increase in turbidity is expec ted. However, the opposite is seen in Figure 6. For both pH levels, the turbidity levels decreased. Therefore, it leads to the conclusion that the amount of elemental sulfur prod uced is too small to create a signal for turbidity. This leads to the question of what is a ctually contributing to turbidity levels in

PAGE 77

62 this water. When looking into this issue, it was d etermined that the majority of the particles were organic in nature (Minnis et. al, 20 05). -1.0 -0.5 0.0 0.5 1.0 1.5 Raw WaterH2O2 OnlyUV OnlyH2O2 -UVlog (Turbidity, NTU) Ambient pH pH 8.2 Figure 14: Average turbidity values for ambient pH and pH 8.2 When chlorine was added after the pretreatments, it oxidized the remaining sulfide in the water. The end product of sulfide o xidation by chlorine is sulfate above a pH of 7.5 (Cadena, 1988) according to the reaction + -+ + + Cl H SO HS OCl4 42 4 and forms elemental sulfur according to the reactio n -+ + + OH Cl S HS OCl0. Figure 11 shows the potential pathways for these re actions. The elemental sulfur predictions are outlined in Tables 22 and 23.

PAGE 78

63 Table 22: Prediction of elemental sulfur produced d uring chlorination after hydrogen peroxide addition Sulfide, mg/L S2Sulfate, mg/L SO4 2% Conversion (S2to SO4 2-) Theoretical Sulfate Produced, mg/L SO4 2(100% conversion) Prediction of amount of elemental sulfur produced, -Ambient pH (1) 1.865 4 71% 5.6 0.533 Ambient pH (2) 1.675 3 90% 5.0 0.675 pH 8.2 (1) 1.51 4 89% 4.5 0.177 pH 8.2 (2) 1.36 3 73% 4.1 0.360 With the addition of chlorine, there was an increas e in turbidity as shown in Figure 15. However, the sulfur generated was very small and cannot account for the turbidity signal. Another possibility source is th at the combined effects of the two oxidants result in the production of turbidity from other sources. Figure 15: Average turbidity values after chlorine addition at ambient pH and pH 8.2 -1 0 1 2 Raw WaterH2O2/NaOClUV/NaOClH2O2/UV/NaOCllog (Turbidity, NTU) Ambient pH pH 8.2

PAGE 79

64 Conclusions & Recommendations Hydrogen peroxide was effective in removing 40 to 4 5% of sulfide at a pH of 8.2 in a pilot flow through system using a hydrogen per oxide-sulfide ratio of 0.5:1. Hydrogen peroxide use as a pretreatment for hydroge n sulfide removal before chlorination is recommended only for those utilitie s that use filters because of the amount of turbidity generated. The hydrogen peroxide also had a positive effect on chlorine demand, reducing it by 8.4 and 1.4 % at ambient pH and pH 8.2 respectively. Acknowledgements Funding for this project was provided by Aloha Util ities, Inc. The assistance of Jack Burke, Mike McDonald, and Charlie Painter of A loha Utilities is appreciated. Salah Albustami and Camilo Romero of USF assisted with fi eld and laboratory analyses.

PAGE 80

65 Conclusions Several alternative oxidation treatments for the re moval of hydrogen sulfide were tested to evaluate the impact on turbidity generati on. The major conclusions from this project are: 1. Turbidity in groundwater is a variable parameter th at depends on many factors including pH. 2. The sources of particles in treated groundwater inc lude mineral precipitates of carbonates, calcium, and magnesium. From the SEM a nalysis, the particles were composed of mostly carbon and oxygen, suggesting th at they are mostly organics. 3. The particles found in the untreated water ranged f rom 1 micron to over 15 microns, while the particles produced from treatmen t were smaller than 1 micron. 4. There is a need for a mechanism to be put into plac e that would remove the particles generated through treatment before the wa ter is sent out to the

PAGE 81

66 distribution because of the high turbidity levels s een by all treatment except UV Only at elevated pH. These turbidity levels exceed the 0.3 NTU turbidity limit set by the Surface Water Treatment Rule. 5. Using hydrogen peroxide only or coupled with UV as a pretreatment for hydrogen sulfide before chlorination is recommended only for water treatment plants that filter because of the turbidity levels generated.

PAGE 82

67 Engineering Implications Historically, groundwater sources were considered t o be relatively safe and for the most part protected from contamination (EPA, 2005). However, societal development and encroachment on natural resources have resulted in increasing vulnerability of groundwater systems. To improve protection of publ ic health, the EPA drafted a proposed groundwater rule that addresses increased disinfection and monitoring. One of the side effects of using disinfectants such as liq uid chlorine, chloramine, and UV irradiation is the potential for generation of part iculate matter. Turbidity is not a water quality parameter that is currently monitored or regulated in groundwater. Turbidity in groundwater cannot be taken lightly as it can serve as a shield for pathogens from disinfectants, can provid e substrate for microorganisms within the distribution system, and can serve as a home fo r organisms to grow on. Based on the research conducted in this project, it is evident t hat the particles present in untreated groundwater should be characterized and their respo nse to disinfectants should be evaluated.

PAGE 83

68 One of the important finds of this study was that t he particles that were generated from disinfectant treatment tended to be in the sub -micron range. One of the implications of this if that if a utility wanted to remove these particles before the treated water is sent out into the distribution system, it could not be a chieved by using conventional granular media filtration. Instead, other methods such as n anofiltration may have to be employed. Or, it may be more feasible to remove the substance s that react with the disinfectants to prevent particle formation before disinfection. This study was completed on a groundwater system in west-central Florida, therefore the conclusions and recommendations drawn may not be applicable to every groundwater system. But, to avoid potential proble ms associated with turbidity generation, a comprehensive study of the groundwate r source and affects of alternative disinfectant treatment needs to be completed before implementation of alternative treatment systems. This will allow a utility to ma ke the best choice in treatment for their groundwater source.

PAGE 84

69 Recommendations for Further Research Recommendations for further research on the effect of disinfection on particle characteristics, and control of hydrogen sulfide in groundwater are presented in this section. 1. Research the particle characteristics found in untr eated and disinfected groundwater using different characterization method s. This would provide additional information about these particles. 2. Research other groundwater system particles and the effect that chlorine, chloramine, and UV irradiation have on the particle characteristics. Turbidity levels should be compared to the findings of this r esearch to establish whether or not there are commonalities among the source waters that may be contributing to the turbidity generation. 3. Research on the reactions and reaction kinetics tha t are occurring when the disinfectants are applied to the water that cause t he particles to form. The kinetic

PAGE 85

70 studies may give insight into the mechanisms of the reactions. This may give engineers the opportunity to establish a way to mak e those reactions unfavorable thus circumventing the problem. 4. Research alternative disinfection treatments such a s ozone and chlorine dioxide, to evaluate whether or not they have an effect on g roundwater particles. This may provide an alternative treatment to chlorine, chlor amine, or UV. 5. Evaluate pretreatment options before disinfection. These pretreatment options include nanofiltration and anion exchange to remove the substances that are present in the groundwater that are reacting with t he disinfectant. This study should be done on a flow-through system, so that th e evaluation more closely mimics a full-scale treatment plant. 6. Research the impact that rainfall has on particle c haracteristics in groundwater. This could give indications on how sensitive the gr oundwater source is to contamination from above ground sources. 7. Research the effect that storage has on sulfide rev ersion in groundwater that has been disinfected. This should be done at different temperatures and storage time lengths to evaluate what happens when water is stag nant in the distribution system. In addition, the reactivity of this water with metals such as copper and

PAGE 86

71 iron should be evaluated. This would provide insig ht onto which conditions promote metal sulfide production and ways to correc t it.

PAGE 87

72 References APHA, AWWA, WEF (1998). Standard Methods for the Examination of Water and Wastewater, 20th Edition. Baltimore, MD. American Water Works Association Research Foundatio n (1995). A Practical Guide to On-Line Particle Counting, Denver, CO. Benjamin, Mark M. (2002). Water Chemistry, International Edition, Singapore. Black, A. P., and Goodson, James, B. Jr. (1952). Th e Oxidation of Sulfides by Chlorine in Dilute Aqueous Solutions. Journal of the American Water Works Association, 4, 309-316. Borril, R. J., and McKean, J. (1993). A New Tool fo r Improving Water Quality—The Particle Monitor, Proc. Of the AWWA Water Quality Technology Conferen ce, Denver, CO. Cadena, Fernando, and Peters, Robert W. (1988). Eva luation of chemical oxidizers for hydrogen sulfide control. Journal Water Pollution Control Federation, 60, 7, 1259-1263. Chang, James C. (1990). Solubility Product Constants. CRC Handbook of Chemistry and Physics. 71st Edition, Boca Raton, FL. Crittenden, John C., Hu, Shumin, Hand, David W., an d Green, Sarah A. (1999). A Kinetic Model For H2O2/UV Process in a Completely Mixed Batch Reactor. Water Resources, 33 (No.10), 2315-2328. Dohnalek, David A., and FitzPatrick, Joseph A. (198 3). The chemistry of reduced sulfur species and their removal from groundwater supplies, Journal of the American Water Works Association, Vol. 75, (6), p 298-308.

PAGE 88

73 Duranceau, Steven J., Lovins, William A. III, Powel l, Robert M., Strully, Michael E. (2003). Turbidity Formation and Removal Following F orced-Draft Aeration. American Water Works Association WQTC Conference. Florida Department of Environmental Protection (200 3). Chapter 62-555.315(5). Retrieved from the World Wide Web on September 30, 2005: http://www.dep.state.fl.us/legal/rules/drinkingwate r/62-555.pdf. Hoffman, M. R. (1977). Kinetics and Mechanism of Ox idation of Hydrogen Sulfide by Hydrogen Peroxide in Acidic Solution. Environmental Science and Technology, 11, (1), 61-66. Kang Joon-Wun, Lee, Kyung-Hyuk (1997). A Kinetic Mo del of the Hydrogen Peroxide/UV Process for the Treatment of Hazardous Waste Chemicals. Environmental Engineering Science, 14 (No. 3), 183-192. Knox, J. (1906). Zur Kenntnis der Ionenbildung des Schwefels und der Komplexionen des Quecksilbers. Z Electochem., 12, 477-481. Levine, Audrey D., Raymer, Blake J., and Jahn, John a (2004). Hydrogen sulfide and turbidity control using catalysed oxidation coupled with filtration for groundwater treatment. Journal of Water Supply Research and Technology—AQU A, vol.53, (5), 325-337. Levine, Audrey D., Minnis, Rochelle J., Al Bustami, Salah, Romero, Camilo, and Dodge, Barbara M. (2005). Evaluation of alternative techno logies for control of hydrogen sulfide from groundwater sources in the Seven Sprin gs Service Area. Lide, David R. ((1990). CRC Handbook of Chemistry a nd Physics. 71st Edition, Boca Raton, Fl. Lopez, Antonio, Bozzi, Anna, Mascolo, Guiseppe, and Kiwi, John. (2003). Kinetic investigation on UV and UV/H2O2 degradations of pharmaceutical intermediates in aqueous solution. Journal of Photochemistry and Photobiology A: Chemi stry, 156, 121-126. Lyn, T., and Taylor J., (1992), Assessing Sulfur Tu rbidity Formation Following Chlorination and Corrosion Control. Journal of American Water Works Association, 90, 3, 74-88. Marony, G. (1959). Constnats de dissociation de l’h ydrogen sulfure. Electrochim. Acta., 1, 58-69. McCarthy, J. F., and Deguelder, C. (1993), Sampling a nd Characterization of Colloids and Particles in Groundwater for Studying Their Rol e in Contaminant Transport.

PAGE 89

74 Chapter 6 in Environmental Particles Vol. 2, edited by Jacques Buffle and Herman P. van Leeuwen, Environmental Analytical and Physical Chemistry Series, CRC Press, Inc. Boca Raton, Florida. Stumm, W., and Morgan J. J. (1996). Aquatic Chemistry, John Wiley & Sons, New York. Tomar, M. Abdullah, T.H.A. (1994). Evaluation of Ch emicals to control the generation of Malodorous Hydrogen Sulfide in Wastewater, Water Research, 45, (2), 145152. U.S. Environmental Protection Agency (1993). Append ix B. Determination of Turbidity by Nephelometry. Environmental Monitoring Systems L aboratory, Office of Research and Development, U.S. Environmental Protec tion Agency, Cincinatti, Ohio 45268. U. S. Environmental Protection Agency (2005), Groun dwater and Drinking Water. Retrieved September 1, 2005 from the World Wide Web : http://www.epa.gov/safewater. U.S. Environmental Protection Agency (2000). The Gr oundwater Rule. Retreived from the World Wide Web: http://www.epa.gov/safewater/gw r.html. U.S. Environmental Protection Agency (1999). EPA Gu idance Manual for Compliance with the Interim Enhanced Surface Water Treatment R ule: Turbidity Provisions. U. S. Peroxide. Retrieved September 29, 2005 from t he World Wide Web: http://www.h2o2.com.

PAGE 90

75 Bibliography Fitts, Charles R. (2002) Groundwater Science. Elsevier Science Ltd. Academic Press London, UK. Levine, Audrey D., Viciere Joseph, Xu, Tianbo, and Sallam, Mayssoon. Preliminary Comparison of the Use of Formazin and Styrene Divin yl Benzene as Standards for Calibration of Nephelometric Turbidity. Univers ity of South Florida, Tampa, FL. Lin, Shu-Sung, and Gurol, Mirate D. (1998). Catalyt ic Decomposition of Hydrogen Peroxide on Iron Oxide: Kinetics, Mechanism, and Im plications. Environmental Science and Technology, 32, 1417-1423. Miller, Christopher M., and Valentine, Richard L. ( 1999). Mechanistic Studies of Surface Catalyzed H2O2 Decomposition and Contaminant Degradation in The P resence of Sand. Pergammon, 33 (No. 12), 2805-2816. Morse, John W., Millero, Frank J., Cornwel, Jeffrey C., and Rickard, David (1987). The Chemistry of the Hydrogen Sulfide and Iron Sulfide Systems in Natural Waters. Earth Science Reviews, 24, 1-42. Price, Michael (1996). Introducing Groundwater. Chapman & Hall, 2-6 Boundary Row, London, UK. Thampi, Mohan V. (1991). Water Treatment Controlled by H2S Levels. Water Engineering & Management, 138 (No. 5), 42-44. Truong, Giang Le, De Laat, Joseph, Legube, Bernard (2004). Effects of chloride and sulfate on the rate of oxidation of ferrous iron by H2O2. Water Research, 38, 2384-2394. Wang, Gen-Shuh, Liao, Chih-Hsiang, and Wu, Fang-Jui (2001). Photodegradation of humic acids in the presence of hydrogen peroxide. Chemosphere, 42, 379-387.

PAGE 91

76 Weishar, James L., Aiken, George R., Bergamaschi Br ian A., Fram, Miranda S., Fujii, Roger, and Mopper, Kenneth (2003). Evaluation of Sp ecific Ultraviolet Absorbance as an Indicator of the Chemical Composit ion of Reactivity of Dissolved Organic Carbon. Environmental Science & Technology, 37 (No. 20), 4702-4708.

PAGE 92

77 Appendices

PAGE 93

78 Appendix A: Pilot Plant Design and Operation The pilot plant consisted of pipe reactors that sim ulated plug flow reactors, chemical injection ports, sample taps and a UV unit Two inch diameter clear schedule 40 PVC pipes were used as the reactors and inch d iameter clear schedule 40 PVC pipes were used as connectors. There were five chemical injection ports included for sodium hydroxide (pH control), hydrogen peroxide, sodium h ypochlorite, ammonium hydroxide, and a corrosion inhibitor. The UV unit is located between the hydrogen peroxide injection port and the sodium hypochlorite injectio n port. A schematic of the pilot plant is shown in Figure 1. The flow rate was controlled by a flow meter that ranged from 0 to 2 gallons per minute. The injection pumps were low flow pump and tank systems. The flowrate varied from approximately 3 mL/min to appr oximately 17 mL/min.

PAGE 94

Figure A 1: Schematic of Pilot Plant Unit 79 Appendix A (continued)

PAGE 95

80 Appendix A (continued) The detention times for the reactors in the pilot p lant are outlined in Table 1. Table A 1: Detention times of reactors From To Detention Time (min) Inlet Outlet 22 Inlet pH Injection ~0 pH Injection Hydrogen Peroxide Injection 1 Hydrogen Peroxide Injection UV Unit 1 UV Unit Chlorine Injection 5 Chlorine Injection Ammonium Hydroxide Injection 3 Ammonium Hydroxide Injection Outlet 10 The detention times were verified using a tracer te sts. The first tracer test was completed using a saturated salt solution to verify the overall detention time of the pilot. The salt solution was injected at the pH injection port (residence time between inlet and pH injection port ~0) and conductivity measurements were taken in one minute intervals

PAGE 96

81 Appendix A (continued) for forty minutes. This is illustrated in Figure 1 a. After the overall residence time was verified, tracer tests needed to be conducted on in dividual reactor times. Again, a saturated salt solution was injected at the pH inje ction port and conductivity measurements were taken in twenty second intervals. This is illustrated in Figure 1b.

PAGE 97

82 Appendix A (continued) a) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 010203040 Time (min)Conductivity (mS/cm) b) 0.0 0.5 1.0 1.5 2.0 2.5 0200400600800100012001400 Time (seconds)Conductivity (mS/cm) After UV Chlorine injection Ammonia Injection Figure A 2: Results from tracer tests for a) the en tire pilot plant and b) the individual reactors Before operation, the pilot plant is run at full sp eed to allow any impurities to flush through the system with the chemical pumps tu rned off. While the pilot plant is

PAGE 98

83 Appendix A (continued) flushing, the chemical concentrations in the tank w ere taken. Once the pilot has flushed, then the flow rate desired is set. For the experim ents run, the preferred flow rate was 1 gallon per minute. Before every run, the initial hydrogen sulfide conc entration in the water was taken. This was the basis for the calculated dosag es for the chemicals. The sodium hypochlorite (liquid chlorine) dose was based on a molar ratio of 5 moles of chlorine for every mole of sulfide. The residual chlorine was t hen measured. The pumps were then manually adjusted to obtain the desired chlorine re sidual. The ammonium chloride dose was based on a mole ratio of 1 mole of ammonia per 4 moles of chlorine. The hydrogen peroxide dose was based on a mass ratio of 0.5 mg o f hydrogen peroxide per mg of sulfide. The chemical pumps were then set to dose the system correctly.

PAGE 99

84 Appendix B: Procedure for Hydrogen Peroxide Measure ment The following section describes in detail the proce dure used to measure hydrogen peroxide. The method was developed by Allen Hunter in the USF Environmental Engineering Laboratory. Introduction Titanium ions in aqueous solution form a yellow col ored complex with hydrogen peroxide. This complex absorbs most strongly at 410 nm and can be measured spectrophotometrically to determine hydrogen peroxi de concentrations in the ppm range. Required reagents and equipment 1. Titanium tetrachloride (TiCl4) 2. 6M HCl 3. 125mL Erlenmeyer flask 4. Small glass funnel 5. Spectrophotometer 6. Storage container with tight fitting lid

PAGE 100

85 Appendix B (continued) Warning: Titanium Chloride is highly volatile liquid and hyd rolyzes instantly upon contact with atmospheric moisture to form a dense w hite smoke of HCl and TiO2. Titanium chloride should not be opened outside of a properly functioning fume hood. Chemical resistant gloves and goggles must be worn while working with pure TiCl4. Contact with liquid water is highly energetic and c auses spattering. Procedure for Preparing the Titanium Reagent 1. Place 30 mL of 6M HCl into a 125 or 250mL Erlenmeye r flask. 2. Set a clean and DRY, small (less than 30 grams) gla ss funnel ,with a top diameter greater than that of the flask, into the mouth of the flask so that it rests lightly on top. 3. Make certain the stem of the funnel is at least 1 c m above the surface of the liquid in the flask this prevents clogging of the funnel and reduces the risk the heat evolved in the reaction with the acid ic solution from pushing the TiCl4 back up the funnel. 4. Using a mechanical pipetter with a cotton vapor bar rier tip, add 2.4mL TiCl4 into the funnel. A white smoke will evolve from al l surfaces with the

PAGE 101

86 Appendix B (continued) TiCl4 on them. Eject the pipette tip into the mouth of t he funnel and allow the apparatus to sit until the white smoke trapped in the Erlenmeyer flask has settled and a yellow solid residue (if present) can be seen on the tip of the funnel stem. 5. Rinse the outer surface of the pipette tip and the funnel into the flask with another 20.0 mL of HCl. If any yellow residue still remains, transfer the flask contents into a beaker and dip the funnel tip into the solution until all residue is dissolved. The reagent can now be safely handled outside the fume hood, safety precautions are now similar to th ose of 6-8M HCl. 6. Store the reagent tightly capped in a cool dark pla ce. Hydrogen peroxide determination 1. For a 10 mL volume, add 100mL of the titanium reagent for samples and standards 1-50ppm H2O2. Addition of excess reagent has no apparent effect other than dissolution of the sample. If the absorbance range and variance are outside of working conditions for the instrument, attempt choosing an absorbance cuvette with a different pat h length; Shorter for higher concentrations, and longer for lower concent rations.

PAGE 102

87 Appendix B (continued) 2. Prepare a linear calibration curve using known conc entrations of H2O2. Add equal portions of the titanium reagent to sampl es and standards. Blank the spectrophotometer with a deionized water sample treated with the titanium reagent. Make sample measurements with respect to the calibration curve. Some instruments allow direct me asurement after establishing an internal calibration curve using st andards. Interferences 1. Strongly alkaline samples may need to be partially neutralized before determination. Reagent E is strongly acidic, but a high pH can cause precipitation of the titanium ions and complexes. 2. Turbidity will interfere with any absorption method Filtration of sample prior to reagent addition or other turbidity reduct ion method may be incorporated. Intermediate turbidity can be handle d by blanking with a untreated sample – standard additions should be use d to verify linearity of calibration under these conditions. If calibration deviates significantly from linear, reduce turbidity by another means befo re analysis. 3. Any substance with a strong absorbance at 410 nm wi ll cause a positive interference and a loss of sensitivity.

PAGE 103

88 Appendix C: Bench Scale and Pilot Plant Data Table C 1: Peroxide sulfide ratio = 1:1 (well 9)... ................................................... .........90 Table C 2: Peroxide sulfide ratio 2:1 (well 9)..... ................................................... ...........90 Table C 3: Peroxide sulfide ratio 3:1 (well 9)..... ................................................... ...........91 Table C 4: Peroxide sulfide ratio 4:1 (well 9)..... ................................................... ...........92 Table C 5: Peroxide sulfide ratio 5:1 (well 9)..... ................................................... ...........93 Table C 6: Peroxide sulfide ratio 6:1 (well 9)..... ................................................... ...........94 Table C 7: Chlorine demand data for well 1 at ambie nt pH.............................................9 4 Table C 8: Chlorine demand data for well 1 at pH 8. 3.................................................. ...95 Table C 9: Chlorine demand data for well 2 at ambie nt pH.............................................9 5 Table C 10: Chlorine demand data for well 2 at pH 8 .3................................................. ..96 Table C 11: Chlorine demand data for well 3 at ambi ent pH...........................................96 Table C 12: Chlorine demand data for well 3 at pH 8 .3................................................. ..97 Table C 13: Chlorine demand data for well 4 at pH 8 .3................................................. ..97 Table C 14: Chlorine demand data for well 6 at ambi ent pH...........................................97 Table C 15: Chlorine demand data for well 6 at pH 8 .3................................................. ..98 Table C 16: Chlorine demand data for well 7 at ambi ent pH...........................................98 Table C 17: Chlorine Demand data for well 7 at pH 8 .3................................................. .99

PAGE 104

89 Table C 18: Chlorine demand data for well 8 at ambi ent pH...........................................99 Table C 19: Chlorine demand data for well 8 at pH 8 .3................................................. 100 Table C 20: Chlorine demand data for well 9 at ambi ent pH.........................................100 Table C 21: Chlorine demand data for well 9 at pH 8 .3................................................. 100 Table C 22: Combined peroxide, chlorine and ammonia runs at well 2 10/20/2004.....101 Table C 23: Combined peroxide chlorine and ammonia runs at well 3 11/10/2004 at pH 7.8.......................................... ................................................... .........102 Table C 24: Combined peroxide, chlorine and ammonia runs at well 3 11/10/2004 at pH 7.8.......................................... ................................................... .........103 Table C 25: Combined peroxide, chlorine and ammonia runs at well 4 11/11/2004 at pH 7.8.......................................... ................................................... .........104 Table C 26: Combined peroxide, chlorine and ammonia runs at well 4 11/11/2004 at pH 8.2.......................................... ................................................... .........106 Table C 27: Combined peroxide, chlorine and ammonia runs at well 8 10/19/2004 at pH 8.3.......................................... ................................................... .........107 Table C 28: Combined peroxide chlorine and ammonia runs at well 9 10/18/2004 at pH 8.3.......................................... ................................................... .........109 Table C 29: Field tests to test oxidant combination s at ambient pH 8/15/2005.............111 Table C 30: Field tests to test oxidant combination s at pH 8.2 8/23/2005....................115 Table C 31: Field tests to test oxidant combination s at ambient pH 9/5/2005..............119 Table C 32: Field tests to test oxidant combination s at pH 8.2 9/10/2005....................123

PAGE 105

90 Appendix C (continued) Bench Scale Tests Table C 1: Peroxide sulfide ratio = 1:1 (well 9) Sulfide, mg S2-/L Time, min pH 7.8 pH 7.9 pH 8.0 pH 8.1 pH 8.2 pH 8.3 pH 8.4 pH 8.5 0 3.0445 2.7240 3.8457 3.6854 2.5638 3.2047 2.7240 2. 5638 1 3.0445 2.2433 3.6854 2.7240 2.4035 2.4035 2.5638 2.7240 2 1.2819 2.4035 2.2433 2.5638 2.4035 2.0831 2.5638 1.9228 3 1.6024 1.2819 1.9228 1.7626 1.7626 2.2433 2.2433 1.9228 4 2.0831 1.2819 1.9228 1.9228 2.0831 2.0831 3.0445 1.4421 5 1.4421 0.9614 2.0831 1.9228 1.7626 2.0831 1.9228 1.6024 6 0.6409 1.6024 2.0831 1.9228 1.4421 2.0831 1.4421 7 2.7240 0.8012 1.7626 2.2433 1.6024 1.6024 1.7626 8 0.9614 1.4421 1.6024 1.6024 1.1217 1.9228 1.602 4 Table C 2: Peroxide sulfide ratio 2:1 (well 9) Sulfide, mg S2-/L Time, min pH 7.8 pH 8.0 pH 8.2 pH 8.3 pH 8.4 pH 8.5 0 2.5638 2.8842 2.724 3.3650 2.8842 3.3650 1 2.4035 2.5638 2.5638 2.2433 2.7240 2.5638 2 1.4421 2.0831 2.724 2.2433 2.4035 2.0831 3 1.2819 1.6024 2.2433 2.2433 2.2433 1.7626

PAGE 106

91 Appendix C (continued) Table C 2: continued 4 0.9614 1.4421 2.0831 1.9228 1.9228 1.7626 5 0.8012 0.8012 1.9228 1.9228 1.7626 1.9228 6 1.1217 1.6024 1.9228 1.7626 1.9228 7 1.4421 1.9228 1.7626 1.9228 8 1.4421 1.2626 1.4421 1.6024 9 1.4421 1.4421 1.4421 1.6024 10 1.6024 1.6024 1.4421 1.4421 Table C 3: Peroxide sulfide ratio 3:1 (well 9) Sulfide, mg S2-/L Time, min pH 8.0 pH 8.2 pH 8.4 pH 8.6 0 2.724 2.8842 2.7240 3.2047 1 2.0831 2.2433 2.8842 2.5638 2 1.6024 2.2433 2.5638 2.0831 3 1.6024 2.2433 2.2433 2.0831 4 1.4421 2.0831 1.9228 2.0831 5 1.2819 1.7626 1.9228 2.2433 6 1.6024 1.7626 2.2433 7 1.4421 1.7626 1.9228 8 1.4221 1.9228 1.9228 9 1.2819 1.9228 1.9228

PAGE 107

92 Appendix C (continued) Table C 4: Peroxide sulfide ratio 4:1 (well 9) Sulfide, mg S2-/L Time, min pH 8.0 pH 8.2 pH 8.4 pH 8.6 0 2.8842 2.7240 2.8842 3.3650 1 2.2433 2.7240 2.2433 2.7240 2 2.0831 2.4035 2.2433 2.5638 3 1.9228 2.5638 2.5638 1.9228 4 1.7626 2.2433 2.5638 1.7626 5 1.4421 1.9228 1.9228 1.7626 6 1.1217 1.7626 1.9228 1.7626 7 1.2819 1.6024 1.7626 1.9228 8 0.9614 1.9228 1.9228 2.0831 9 1.7626 1.7626

PAGE 108

93 Appendix C (continued) Table C 5: Peroxide sulfide ratio 5:1 (well 9) Sulfide, mg S2-/L Time, min pH 8.0 pH 8.2 pH 8.4 pH 8.6 0 2.5638 3.3650 2.8842 3.2047 1 2.724 2.7240 2.4035 2.8842 2 2.2433 2.7240 2.7240 2.7240 3 2.4035 2.2433 2.5638 2.2433 4 2.4035 2.2433 2.5638 2.0831 5 2.0831 1.9228 2.5638 2.2433 6 1.7626 2.0831 2.2433 7 1.6024 2.8842 1.9228 2.2433 8 1.7626 2.0831 1.7626 2.2433 9 1.6024 2.0831 1.9228 2.2433

PAGE 109

94 Appendix C (continued) Table C 6: Peroxide sulfide ratio 6:1 (well 9) mg S2-/L Time, min pH 8.0 pH 8.2 pH 8.4 pH 8.6 0 3.2047 3.2047 2.8842 2.5638 1 2.4035 3.0445 2.4035 2.8842 2 2.5638 2.8842 2.2433 2.0831 3 2.2433 2.4035 2.2433 2.5638 4 2.0831 2.4035 2.0831 2.2433 5 1.9228 2.0831 2.0831 1.4421 6 1.4421 2.0831 1.7626 1.6024 7 1.6024 2.5638 1.9228 1.6024 8 1.4421 2.5638 1.6024 1.4421 9 1.2819 2.2433 1.4421 1.6024 Table C 7: Chlorine demand data for well 1 at ambie nt pH Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 7.14 0.00 0.00 0 90 10.58 7.16 0.00 0.00 5 7.17 0.28 4.00 6.58 10 7.17 4.00 6.58 15 7.18 0.37 3.70 6.88 20 7.19 3.70 6.88

PAGE 110

95 Appendix C (continued) Table C 8: Chlorine demand data for well 1 at pH 8. 3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0.00 0.00 8.29 0.000 0.00 0 80.00 9.41 8.34 0.000 0.00 5 8.34 0.460 3.500 5.91 10 8.33 3.400 6.01 15 8.33 0.360 3.000 6.41 20 8.32 2.900 6.51 Table C 9: Chlorine demand data for well 2 at ambie nt pH Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 7.47 0.59 0.00 0.00 0 120 14.11 7.53 0.00 0.00 5 7.51 3.20 10.91 10 7.51 1.00 3.20 10.91 15 7.51 1.39 3.30 10.81 20 7.53 1.04 3.20 10.91

PAGE 111

96 Appendix C (continued) Table C 10: Chlorine demand data for well 2 at pH 8 .3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 8.30 0.00 0.00 0 120 14.11 8.37 0.00 0.00 5 8.37 6.50 7.61 10 8.38 5.90 8.21 15 8.37 5.60 8.51 20 8.37 5.60 8.51 Table C 11: Chlorine demand data for well 3 at ambi ent pH Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 7.53 0.00 0.00 0 140 16.46 7.64 0.52 0.00 0.00 5 0 7.64 4.30 12.16 10 0 7.58 0.75 4.00 12.46 15 0 7.58 3.80 12.66 20 0 7.58 1.04 3.70 12.76

PAGE 112

97 Appendix C (continued) Table C 12: Chlorine demand data for well 3 at pH 8 .3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0.00 0.00 8.32 0.000 0.00 0 140.00 16.46 8.43 1.030 0.000 0.00 5 8.43 4.800 11.66 10 8.39 1.880 4.400 12.06 15 8.38 4.100 12.36 20 8.38 2.270 4.000 12.46 Table C 13: Chlorine demand data for well 4 at pH 8 .3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 7.42 0.00 0 200 23.52 7.52 0.00 10 7.51 0.52 6.50 17.02 20 7.52 0.63 5.80 17.72 Table C 14: Chlorine demand data for well 6 at ambi ent pH Time (min) NaOC l (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 7.28 0.47 0.00 0.00 0 130 15.29 7.37 0.00 0.00 5 7.42 0.66 5.50 9.79 10 7.42 0.62 5.50 9.79 15 7.43 5.10 10.19 20 7.43 4.90 10.39

PAGE 113

98 Appendix C (continued) Table C 15: Chlorine demand data for well 6 at pH 8 .3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 8.30 0.00 0.00 0 120 14.11 8.38 0.00 0.00 5 8.35 0.34 6.70 7.41 10 6.80 7.31 15 0.65 5.70 8.41 20 5.80 8.31 Table C 16: Chlorine demand data for well 7 at ambi ent pH Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 7.37 2.86 0.00 0.00 0 60 7.06 7.40 0.00 0.00 5 7.44 3.50 3.56 10 7.43 2.48 4.00 3.06 15 7.44 3.10 3.96 20 7.44 3.00 4.06

PAGE 114

99 Appendix C (continued) Table C 17: Chlorine Demand data for well 7 at pH 8 .3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0.00 0.00 8.30 2.680 0.000 0.00 3 70.00 8.23 8.34 0.000 0.00 9 8.33 5.400 2.83 14 8.33 2.270 4.500 3.73 19 8.32 4.100 4.13 28 8.32 4.000 4.23 Table C 18: Chlorine demand data for well 8 at ambi ent pH Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 300.00 17.64 7.40 0.00 2 7.45 0.00 5 7.45 4.30 13.34 10 7.45 2.08 4.1 13.54 15 7.46 3.5 14.14 20 7.46 3.2 14.44

PAGE 115

100 Appendix C (continued) Table C 19: Chlorine demand data for well 8 at pH 8 .3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 8.32 0.00 0.00 3 320 18.82 8.40 1.34 0.00 0.00 5 8.40 5.20 13.62 10 8.38 5.40 13.42 15 8.38 5.40 13.42 20 8.38 5.40 13.42 Table C 20: Chlorine demand data for well 9 at ambi ent pH Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0.00 0.00 7.42 0.00 0.00 0 280.00 32.93 7.53 1.36 0.00 0.00 5 7.49 5.50 27.43 10 7.48 4.17 5.20 27.73 15 7.46 4.80 28.13 20 7.45 8.70 4.10 28.83 Table C 21: Chlorine demand data for well 9 at pH 8 .3 Time (min) NaOCl (L) NaOCl (mg/L Cl2) pH Turbidity, NTU Residual Cl2, mg/L Cl2 Chlorine Demand, Cl2 0 0 0.00 8.29 0.00 0.00 0 260 30.58 8.54 0.00 0.00 5 8.45 6.50 24.08 10 8.44 2.30 5.60 24.98 15 8.41 5.00 25.58 20 8.41 7.84 4.50 26.08

PAGE 116

Table C 22: Combined peroxide, chlorine and ammonia runs at well 2 10/20/2004 Initial Conditions: Temp. (C) Conductivity (S/cm) ORP (mV) pH Turbidity (NTU) DO (mg/L) Sulfide (mg/L) 25.8 402 61 7.57 0.222 0.41 0.88 Set Parameters: pH Volume (L) Peroxide ratio 8.3 2 0.5:1 Temp. (C) Time (min) H2S (mg/L) measured by probe pH H2O2 added (L) Cl2 Added (L) Residual Cl2 (mg/L) Turbidity (NTU) NH3 Added (L) Residual Chloramine (mg/L as Cl2) Free NH3 (mg/L as N) 26.4 0 -8.30 0 0 0 -0 0 0 26.6 0 0.804 8.30 29.5 0 0 -0 0 0 26.7 1 0.407 8.29 0 0 0 -0 0 0 26.8 2 0.299 8.28 0 0 0 -0 0 0 26.9 4 0.231 8.29 0 0 0 -0 0 0 27 6 0.190 8.28 0 0 0 -0 0 0 27.1 8 0.124 8.28 0 0 0 -0 0 0 27.2 --8.27 0 80 0.6 0.181 0 0 0 101 Appendix C (continued)

PAGE 117

Table C 22: Continued 27.3 --8.28 0 40 1.4 -0 0 0 27.5 --8.29 0 40 1.9 0.202 0 0 0 27.8 --8.30 0 40 2.6 -0 0 0 27.9 --8.29 0 40 3.4 0.238 0 0 0 28 --8.29 0 40 4.1 -0 0 0 28.2 --8.30 0 40 5.4 0.245 0 0 0 28.6 --8.43 0 0 --148 0 0 28.6 --8.43 0 0 4.9 0.238 0 4.35 0 Table C 23: Combined peroxide chlorine and ammonia runs at well 3 11/10/2004 at pH 7.8 Initial Conditions: Temp. (C) Conductivity (S/cm) ORP (mV) pH Turbidity (NTU) DO (mg/L) Sulfide (mg/L) 25 400 -118 7.48 0.162 1.02 1.372 Set Parameters: pH Volume (L) Peroxide ratio 7.8 2 0.5:1 102 Appendix C (continued)

PAGE 118

Table C 23: Continued Temp. (C) Time (min) H2S (mg/L) pH H2O2 added (L) Cl2 Added (L) Residual Cl2 (mg/L) Turbidity (NTU) NH3 Added (L) Residual Chloramine (mg/L as Cl2) Free NH3 (mg/L as N) -0 1.715 7.8 57.5 0 0 0.162 0 0 0 -1 1.407 7.8 -0 0 -0 0 0 -2 1.177 7.8 -0 0 -0 0 0 -2 -7.8 -280 1.7 0.336 0 0 0 ---7.83 --0 -0 0 0 Table C 24: Combined peroxide, chlorine and ammonia runs at well 3 11/10/2004 at pH 7.8 Initial Conditions: Temp. (C) Conductivity (S/cm) ORP (mV) pH Turbidity (NTU) DO (mg/L) Sulfide (mg/L) 25 400 -118 7.48 0.162 1.02 1.718 Set Parameters: pH Volume (L) Peroxide ratio 8.2 2 0.5:1 103 Appendix C (continued)

PAGE 119

Table C 24: Continued Temp. (C) Time (min) H2S (mg/L) measured by probe pH H2O2 added (L) Cl2 Added (L) Residual Cl2 (mg/L) Turbidity (NTU) NH3 Added (L) Residual Chloramine (mg/L as Cl2) Free NH3 (mg/L as N) 25 0 -8.2 57.5 0 0 -0 0 0 25 1 0.734 8.2 -0 0 -0 0 0 25.1 2 0.646 8.2 -0 0 -0 0 0 25.1 2 -8.28 -350 5.9 0.484 0 0 0 -5 min after last chlorine dose -----8.1 1.59 below detecti on limit (0.04) Table C 25: Combined peroxide, chlorine and ammonia runs at well 4 11/11/2004 at pH 7.8 Initial Conditions: Temp. (C) Conductivity (S/cm) ORP (mV) pH Turbidity (NTU) DO (mg/L) Sulfide (mg/L) 25 424 -105 7.37 0.506 0.9 1.254 (probe)/1.000 (spec) 104 Appendix C (continued)

PAGE 120

Table C 25: Continued Set Parameters: pH Volume (L) Peroxide ratio 7.8 2 0.5:1 Temp. (C) Time (min) H2S (mg/L) measured by probe pH H2O2 added (L) Cl2 Added (L) Residual Cl2 (mg/L) Turbidity (NTU) NH3 Added (L) Chloramine formed (mg/L as Cl2) Free NH3 (mg/L as N) 25 0 -7.8 41.8 0 0 -0 0 0 25 1 0.413 7.8 -0 0 -0 0 0 25.1 2 0.32 7.8 -0 0 -0 0 0 25.1 2 -7.8 -280 5 -0 0 0 25.1 7 -7.95 ---0.315 13.8 3.31 0.23 105 Appendix C (continued)

PAGE 121

Table C 26: Combined peroxide, chlorine and ammonia runs at well 4 11/11/2004 at pH 8.2 Initial Conditions: Temp. (C) Conductivity (S/cm) ORP (mV) pH Turbidity (NTU) DO (mg/L) Sulfide (mg/L) 25 424 -105 7.37 0.506 0.9 1.254 (probe)/1.000 (spec) Set Parameters: pH Volume (L) Peroxide ratio 8.2 2 0.5:1 Temp. (C) Time (min) H2S (mg/L) measured by probe pH H2O2 added (L) Cl2 Added (L) Residual Cl2 (mg/L) Turbidity (NTU) NH3 Added (L) Chloramine formed (mg/L as Cl2) Free NH3 (mg/L as N) 25 0 -8.21 42 0 0 -0 0 0 25 1 0.932 8.21 -0 0 -0 0 0 25.1 2 0.792 8.21 -0 0 -0 0 0 25.1 2 -8.23 -300 3 0.162 0 0 0 106 Appendix C (continued)

PAGE 122

Table C 26: Continued 25.2 7 -8.23 -30 3.9 -8.1 1.59 -25.7 --8.23 -30 4.6 ----26.1 5 min after last chlorine addition -8.34 ---0.568 12.7 3.92 Below detection limit Table C 27: Combined peroxide, chlorine and ammonia runs at well 8 10/19/2004 at pH 8.3 Initial Conditions: Temp. (C) Conductivity (S/cm) ORP (mV) pH Turbidity (NTU) DO (mg/L) Sulfide (mg/L) 25.5 494 -34 7.27 6 0.8 1.06 Set Parameters: pH Volume (L) Peroxide ratio 8.3 2 0.5:1 107 Appendix C (continued)

PAGE 123

Table C 27: Continued Temp. (C) Time (min) H2S (mg/L) measured by probe pH H2O2 added (L) Cl2 Added (L) Residual Cl2 (mg/L) Turbidity (NTU) NH3 Added (L) Chloramine formed (mg/L as Cl2) Free NH3 (mg/L as N) 25.5 0 -8.3 0 0 0 25.5 0 1.048 8.3 34 0 0 -1 0.593 8.3 0 0 0 26.4 2 0.482 8.29 0 0 0 26.5 4 0.376 8.29 0 0 0 -6 0.319 8.29 0 0 0 -8 0.249 8.29 0 0 0 ---8.27 0 120 0.8 ---0 40 1.6 27.4 --8.28 0 40 2.6 27.5 --8.28 0 40 3.2 27.7 --8.28 0 40 4.5 27.8 --8.29 0 40 6 28 --8.41 0 0 0 28 --8.41 0 0 5 108 Appendix C (continued)

PAGE 124

Table C 28: Combined peroxide chlorine and ammonia runs at well 9 10/18/2004 at pH 8.3 Initial Conditions: Temp. (C) Conductivity (S/cm) ORP (mV) pH Turbidity (NTU) DO (mg/L) Sulfide (mg/L) 24.9 479 -126 7.34 0.181 0.71 2.77 Set Parameters: pH Volume (L) Peroxide ratio 8.3 2 0.5:1 Temp. (C) Time (min) H2S (mg/L) measured by probe pH H2O2 added (L) Cl2 Added (L) Residual Cl2 (mg/L) Turbidity (NTU) NH3 Added (L) Chloramine formed (mg/L as Cl2) Free NH3 (mg/L as N) 25.1 0 -8.3 0 0 0 -0 0 0 25.2 0 -8.3 100 0 0 -0 0 0 25.2 1 2.106 8.3 0 0 0 -0 0 0 25.3 2 1.722 8.31 0 0 0 -0 0 0 25.4 4 1.15 8.33 0 0 0 -0 0 0 25.6 6 0.89 8.33 0 0 0 -0 0 0 25.7 8 0.881 8.32 0 0 0 -0 0 0 25.9 9 -8.34 0 320 3 0.94 0 0 0 109 Appendix C (continued)

PAGE 125

Table C 28: Continued 26 --8.32 0 20 2.6 -0 0 0 26.6 --8.3 0 20 2.4 4.31 0 0 0 26.8 --8.29 0 20 3.1 -0 0 0 27 --8.29 0 20 3.8 5.67 0 0 0 27.2 --8.28 0 20 3.6 -0 0 0 27.6 --8.27 0 20 3.8 -0 0 0 ---0 20 3.9 7.11 0 0 0 ---0 40 5.1(t)/ 4.7 (f) -0 0 0 28.3 --8.36 0 0 0 -14.1 0 0 ---8.36 0 0 0 8.2 0 3.69 0.05 (lower limit) 110 Appendix C (continued)

PAGE 126

111 Appendix C (continued) Table C 29: Field tests to test oxidant combination s at ambient pH 8/15/2005 Sample Number Treatment Temperature, C pH Alkalinity, mg/L CaCO3 Conductivity, S/cm Dissolved Oxygen, mg/L O2 1 Raw Water 26.5 7.41 190 528 0.22 2 H2O2 Only 26.8 7.42 200 531 0.11 3 H2O2/UV 27.7 7.45 190 539 0.64 4 H2O2/UV/NH2Cl 28.5 7.83 220 635 0.86 5 H2O2/UV/NaOCl 28.7 7.49 190 618 0.82 6 H2O2/NaOCl 28.8 7.50 200 679 1.51 7 H2O2/NH2Cl 29.1 7.85 200 697 0.63 8 UV Only 28.9 7.45 200 555 0.41 9 UV/NaOCl 29.4 7.48 190 694 0.95 10 UV/NH2Cl 29.5 7.98 210 710 1.08 11 NaOCl Only 29.7 7.27 190 697 1.01 12 NH2Cl Only 30.0 7.94 210 731 0.90

PAGE 127

112 Appendix C (continued) Table C 29: Continued Sample Number Treatment ORP, mV Turbidity, NTU TOC, mg/L Hydrogen Sulfide, mg/L S2Sulfate, mg/L SO4 2Hydrogen Peroxide Dose, mg/L H2O2 1 Raw Water -187 0.565 2.83 2.455 29 2 H2O2 Only -192 0.121 2.71 1.865 30 1.25 3 H2O2/UV -218 19.8 2.57 1.115 30 1.25 4 H2O2/UV/N H2Cl -36 26.3 2.67 0 33 1.25 5 H2O2/UV/N aOCl -27 29 2.76 0 32 1.25 6 H2O2/NaO Cl 543 23 2.66 0 34 1.25 7 H2O2/NH2C l 310 24.6 3.11 0 34 1.25 8 UV Only -239 11.3 2.49 1.345 35 9 UV/NaOCl 220 14.9 2.51 0 36 10 UV/NH2Cl 275 18.5 2.61 0 34 11 NaOCl Only 295 2.81 2.6 0 36 12 NH2Cl Only 297 2.03 2.69 0 36

PAGE 128

113 Appendix C (continued) Table C 29: Continued Sample Number Treatment Residual Hydrogen Peroxide, mg/L H2O2 UV Intensity Sodium Hypochlorite Dose, mg/L Cl2 Residual Total Chlorine, mg/L Cl2 Residual Free Chlorine, mg/L Cl2 1 Raw Water 2 H2O2 Only 0 3 H2O2/UV 0 13.1 4 H2O2/UV/NH2Cl 13.1 22.51 1.0 1.0 5 H2O2/UV/NaOCl 13.1 22.51 1.0 0.5 6 H2O2/NaOCl 22.51 2.8 2.3 7 H2O2/NH2Cl 22.51 4.8 4.2 8 UV Only 13.1 9 UV/NaOCl 13.1 22.51 1.8 0.4 10 UV/NH2Cl 13.1 22.51 3.6 2.7 11 NaOCl Only 22.51 1.0 0.7 12 NH2Cl Only 22.51 1.9 1.8

PAGE 129

114 Appendix C (continued) Table C 29: Continued Sample Number Treatment Ammonium Chloride Dose, mg/L NH3-N Free Ammonia, mg/L NH3-N Residual Chloramine, mg/L Cl2 1 Raw Water N/A 2 H2O2 Only 3 H2O2/UV 4 H2O2/UV/NH2Cl 2.63 0.9 0.35 5 H2O2/UV/NaOCl 6 H2O2/NaOCl 7 H2O2/NH2Cl 2.63 0.54 4.38 8 UV Only 9 UV/NaOCl 10 UV/NH2Cl 2.63 0.05 3.55 11 NaOCl Only 12 NH2Cl Only 2.63 0.4 1.61

PAGE 130

115 Appendix C (continued) Table C 30: Field tests to test oxidant combination s at pH 8.2 8/23/2005 Sample Number Treatment Temperature, C pH Alkalinity, mg/L CaCO3 Conductivity, uS/cm Dissolved Oxygen, mg/L O2 1 Raw Water 26.3 7.41 190 516 0.37 2 H2O2 Only 27.0 8.23 220 550 0.53 3 H2O2/UV 27.5 8.25 220 561 0.25 4 H2O2/UV/NH2Cl 28.6 8.81 240 670 0.52 5 H2O2/UV/NaOCl 29.4 8.25 230 703 1.01 6 H2O2/NaOCl 28.6 8.12 230 667 1.01 7 H2O2/NH2Cl 28.9 8.81 230 672 1.23 8 UV Only 28.3 7.93 220 569 0.12 9 UV/NaOCl 29.0 8.10 240 666 0.95 10 UV/NH2Cl 29.0 8.75 240 546 1.35 11 NaOCl Only 27.7 8.15 210 660 0.12 12 NH2Cl Only 27.2 8.85 240 652 0.92

PAGE 131

116 Appendix C (continued) Table C 30: Continued Sample Number Treatment ORP, mV Turbidity, NTU TOC, mg/L Hydrogen Sulfide, mg/L S2Sulfate, mg/L SO4 2Hydrogen Peroxide Dose, mg/L H2O2 1 Raw Water -225 0.424 5.3 2.5 25 2 H2O2 Only -254 0.22 3.29 1.71 26 1.19 3 H2O2/UV -252 0.726 2.8 1.36 27 1.19 4 H2O2/UV/NH2Cl 143 13.9 2.66 0 30 1.19 5 H2O2/UV/NaOCl 558 8.66 3.93 0 30 1.19 6 H2O2/NaOCl 287 6.6 2.58 0 30 1.19 7 H2O2/NH2Cl 207 6.47 2.54 0 33 1.19 8 UV Only -187 0.64 2.56 1.25 29 9 UV/NaOCl 406 4.64 2.8 0 33 10 UV/NH2Cl 54 4.31 2.54 0 33 11 NaOCl Only 265 5.58 2.66 0 33 12 NH2Cl Only 184 6.85 2.61 0 33

PAGE 132

117 Appendix C (continued) Table C 30: Continued Sample Number Treatment Residual Hydrogen Peroxide, mg/L H2O2 UV Intensity Sodium Hypochlorite Dose, mg/L Cl2 Residual Total Chlorine, mg/L Cl2 Residual Free Chlorine, mg/L Cl2 1 Raw Water N/A 2 H2O2 Only 0 3 H2O2/UV 0 14.1 4 H2O2/UV/NH2Cl 14.1 21.59 5.3 3.9 5 H2O2/UV/NaOCl 14.1 21.59 4.9 4.2 6 H2O2/NaOCl 21.59 0.9 0.7 7 H2O2/NH2Cl 21.59 0.9 0.7 8 UV Only 14.1 9 UV/NaOCl 14.1 21.59 1.5 0.1 10 UV/NH2Cl 14.1 21.59 2.07 0.1 11 NaOCl Only 21.59 0.6 0.1 12 NH2Cl Only 21.59 0.54 0.5

PAGE 133

118 Appendix C (continued) Table C 30: Continued Sample Number Treatment Ammonium Chloride Dose, mg/L NH3-N Free Ammonia, mg/L NH3N Residual Chloramine, mg/L Cl2 1 Raw Water N/A N/A N/A 2 H2O2 Only 3 H2O2/UV 4 H2O2/UV/NH2Cl 2.15 0.4 4.66 5 H2O2/UV/NaOCl 6 H2O2/NaOCl 7 H2O2/NH2Cl 2.15 0.58 0.8 8 UV Only 9 UV/NaOCl 10 UV/NH2Cl 2.15 1.04 2.21 11 NaOCl Only 12 NH2Cl Only 2.15 1.04 0.68

PAGE 134

119 Appendix C (continued) Table C 31: Field tests to test oxidant combination s at ambient pH 9/5/2005 Sample Number Treatment Temperature, C pH Alkalinity, mg/L CaCO3 Conductivity, uS/cm A. Color T. Color 1 Raw Water 27.1 7.10 190 546 14 14 2 H2O2 Only 28.2 7.39 180 537 12 20 3 H2O2/UV 28.5 7.41 190 534 127 38 4 H2O2/UV/NH2Cl 29.8 7.66 200 958 206 52 5 H2O2/UV/Na OCl 29.5 7.60 230 741 187 29 6 H2O2/NaOCl 30.6 7.49 210 772 135 11 7 H2O2/NH2Cl 30.4 7.56 190 757 221 10 8 UV Only 28.6 7.47 180 550 70 41 9 UV/NaOCl 29.3 7.57 230 722 158 22 10 UV/NH2Cl 29.6 7.53 180 740 136 36 11 NaOCl Only 30.2 7.55 220 765 78 35 12 NH2Cl Only 30.5 8.08 200 775 70 31

PAGE 135

120 Appendix C (continued) Table C 31: Continued Sample Number Treatment ORP, mV Turbidity, NTU TOC, mg/L Sulfide, mg/L S2Sulfate, mg/L SO4 2Hydrogen Peroxide Dose, mg/L H2O2 1 Raw Water -115 0.314 2.55 2.265 31.0 2 H2O2 Only -192 0.48 4.21 1.675 31.0 1.24 3 H2O2/UV -233 24 2.71 0.905 28.0 1.24 4 H2O2/UV/N H2Cl 705 33.8 2.62 33.0 1.24 5 H2O2/UV/N aOCl 679 30.3 3.06 34.0 1.24 6 H2O2/NaO Cl 659 12.1 2.72 34.0 1.24 7 H2O2/NH2C l 375 30.6 3.38 32.0 1.24 8 UV Only -188 16.6 3.03 1.135 30.0 9 UV/NaOCl 662 19.4 2.70 34.0 10 UV/NH2Cl 461 20.1 2.76 31.0 11 NaOCl Only 673 5.77 2.62 34.0 12 NH2Cl Only 391 2.28 2.71 36.0

PAGE 136

121 Appendix C (continued) Table C 31: Continued Sample Number Treatment Residual Hydrogen Peroxide, mg/L H2O2 UV Intensity Sodium Hypochlorite Dose, mg/L Cl2 Residual Total Chlorine, mg/L Cl2 Residual Free Chlorine, mg/L Cl2 1 Raw Water 2 H2O2 Only 0.97 3 H2O2/UV 0.87 13.7 4 H2O2/UV/N H2Cl 13.7 20.72 12.8 6.3 5 H2O2/UV/N aOCl 13.7 20.72 8.8 7.8 6 H2O2/NaO Cl 20.72 4.0 3.7 7 H2O2/NH2C l 20.72 5.8 5.4 8 UV Only 13.7 9 UV/NaOCl 13.7 20.72 6.9 6.9 10 UV/NH2Cl 13.7 20.72 2.5 2.3 11 NaOCl Only 20.72 9.2 8.8 12 NH2Cl Only 20.72 9.2 8.8

PAGE 137

122 Appendix C (continued) Table C 31: Continued Sample Number Treatment Ammonium Chloride Dose, mg/L NH3-N Free Ammonia, mg/L NH3-N Residual Chloramine, mg/L Cl2 1 Raw Water 2 H2O2 Only 3 H2O2/UV 4 H2O2/UV/NH2Cl 1.83 0.05 6.42 5 H2O2/UV/NaOCl 6 H2O2/NaOCl 7 H2O2/NH2Cl 1.83 0.26 4.86 8 UV Only 9 UV/NaOCl 10 UV/NH2Cl 1.83 0.05 0.47 11 NaOCl Only 12 NH2Cl Only 1.83 0.88 9.08

PAGE 138

123 Appendix C (continued) Table C 32: Field tests to test oxidant combination s at pH 8.2 9/10/2005 Sample Number Treatment Temperature, C pH Alkalinity, mg/L CaCO3 Conductivity, uS/cm A. Color T. Color 1 Raw Water 28.2 7.58 200 532 10 9 2 H2O2 Only 29.0 8.32 230 562 14 11 3 H2O2/UV 28.7 8.36 220 550 14 13 4 H2O2/UV/NH2Cl 28.9 8.60 220 650 66 13 5 H2O2/UV/NaOCl 28.2 8.36 300 672 130 14 6 H2O2/NaOCl 28.6 8.35 240 690 116 16 7 H2O2/NH2Cl 29.3 8.53 220 664 106 17 8 UV Only 29.0 8.40 230 564 15 13 9 UV/NaOCl 29.2 8.39 210 692 116 4 10 UV/NH2Cl 28.8 8.56 240 661 120 19 11 NaOCl Only 28.8 8.39 240 688 133 11 12 NH2Cl Only 29.2 8.59 230 682 131 16

PAGE 139

124 Appendix C (continued) Table C 32: Continued Sample Number Treatment ORP, mV Turbidity, NTU TOC, mg/L Sulfide, mg/L S2Sulfate, mg/L SO4 2Hydroge n Peroxide Dose, mg/L H2O2 1 Raw Water 301 0.118 3.00 2.485 36.6 2 H2O2 Only 312 0.211 2.88 1.360 34.7 1.27 3 H2O2/UV 360 0.126 2.63 0.725 34.6 1.27 4 H2O2/UV/NH2Cl 406 18.3 2.66 36.1 1.27 5 H2O2/UV/Na OCl 652 24.7 2.68 36.5 1.27 6 H2O2/NaOCl 609 21.4 2.67 37.3 1.27 7 H2O2/NH2Cl 404 21.5 2.65 37.1 1.27 8 UV Only 330 0.095 2.71 0.985 36.9 9 UV/NaOCl 238 22.5 2.71 37.2 10 UV/NH2Cl 353 21.4 2.69 37.8 11 NaOCl Only 633 23.6 2.70 37.0 12 NH2Cl Only 396 22.2 2.79 36.1

PAGE 140

125 Appendix C (continued) Table C 32: Continued Sample Number Treatment Residual Hydrogen Peroxide, mg/L H2O2 UV Intensity Sodium Hypochlorite Dose, mg/L Cl2 Residual Total Chlorine, mg/L Cl2 Residual Free Chlorine, mg/L Cl2 1 Raw Water 2 H2O2 Only 3 H2O2/UV 0 11.1 4 H2O2/UV/NH2Cl 0 11.1 17.59 6.88 0.6 5 H2O2/UV/NaOCl 11.1 17.59 4.0 3.9 6 H2O2/NaOCl 17.59 3.6 3.6 7 H2O2/NH2Cl 17.59 6.64 1.96 8 UV Only 11.1 9 UV/NaOCl 11.1 17.59 0.4 0.2 10 UV/NH2Cl 11.1 17.59 6.6 0.26 11 NaOCl Only 17.59 3.7 3.6 12 NH2Cl Only 17.59 3.96 2.34

PAGE 141

126 Appendix C (continued) Table C 32: Continued Sample Number Treatment Ammonium Chloride Dose, mg/L NH3N Free Ammonia, mg/L NH3-N Residual Chloramine, mg/L Cl2 1 Raw Water 2 H2O2 Only 3 H2O2/UV 4 H2O2/UV/NH2Cl 1.99 0.82 5.9 5 H2O2/UV/NaOCl 6 H2O2/NaOCl 7 H2O2/NH2Cl 1.99 8 UV Only 9 UV/NaOCl 10 UV/NH2Cl 1.99 11 NaOCl Only 12 NH2Cl Only 1.99

PAGE 142

127 Appendix D: Laboratory Tests Table D 1: Total solids............................ ................................................... .....................129 Table D 2: Total dissolved solids, mg/L............ ................................................... ..........130 Table D 3: Size distribution of raw water particles 8/16/2005.......................................13 1 Table D 4: Size distribution of particles after hyd rogen peroxide treatment at ambient pH 8/16/2005............................... ................................................... .132 Table D 5: Size distribution of particles after hyd rogen peroxide-UV treatment at ambient pH 8/16/2005............................... ................................................... .133 Table D 6: Size distribution of particles after hyd rogen peroxide-UV-chlorineammonia treatment at ambient pH 8/16/2005.......... .....................................134 Table D 7: Size distribution of particles after hyd rogen peroxide-UV-chlorine treatment at ambient pH 8/16/2005.................. .............................................135 Table D 8: Size distribution of particles after hyd rogen peroxide-chlorine treatment at ambient pH 8/16/2005.................. .............................................136 Table D 9: Size distribution of particles after hyd rogen peroxide-chlorine treatment at ambient pH 8/16/2005.................. .............................................137 Table D 10: Size distribution of particles after UV treatment at ambient pH 8/16/2005.......................................... ................................................... .......138 Table D 11: Size distribution of particles after UV -chlorine treatment at ambient pH 8/16/2005....................................... ................................................... ....139 Table D 12: Size distribution of particles after UV -chlorine-ammonia treatment at ambient pH 8/16/2005............................... ..................................................1 40 Table D 13: Size distribution of particles after ch lorine treatment at ambient pH 8/16/2005.......................................... ................................................... .......141

PAGE 143

128 Table D 14: Size distribution of particles after ch lorine-ammonia treatment at ambient pH 8/16/2005............................... ..................................................1 42 Table D 15: Size distribution of particles at eleva ted pH 8/23/2005..............................143 Table D 16: Size distribution of particles at ambie nt pH 9/5/2005................................144 Table D 17: Size distribution of particles at eleva ted pH 9/10/2005..............................145

PAGE 144

Table D 1: Total solids Date 8/15/2005 8/23/2005 9/5/2005 9/10/2005 No. Treatment Average, mg/L Std. Dev., mg/L Average, mg/L Std. Dev., mg/L Average, mg/L Std. Dev., mg/L Average, mg/L Std. Dev., mg/L 1 Raw Water 287 0.79 292 1.57 331 6.29 290 0.00 2 H2O2 Only 286 3.93 300 1.57 323 0.79 307 4.71 3 H2O2/UV 291 3.93 317 6.29 317 5.50 301 3.93 4 H2O2/UV/NH2Cl 320 1.57 313 0.00 483 5.50 312 2.36 5 UV Only 284 2.36 360 1.57 422 1.57 361 5.50 6 UV/NH2Cl 338 0.00 364 4.71 419 7.86 365 0.16 7 NaOCl Only 346 9.43 308 0.79 415 2.36 338 0.79 8 UV/NaOCl 347 1.57 308 2.36 321 0.00 298 11.00 9 NH2Cl Only 346 5.50 361 0.79 401 7.86 363 7.07 10 H2O2/UV/NaOCl 351 2.36 318 2.36 400 1.57 344 1.57 11 H2O2/NaOCl 348 8.64 360 6.29 420 1.57 371 0.79 12 H2O2/NH2Cl 353 0.79 309 11.00 424 7.86 369 9.43 129 Appendix D (continued)

PAGE 145

Table D 2: Total dissolved solids, mg/L Date 8/15/2005 8/23/2005 9/5/2005 9/10/2005 No. Treatment Average, mg/L Std. Dev., mg/L Average, mg/L Std. Dev., mg/L Average, mg/L Std. Dev., mg/L Average, mg/L Std. Dev., mg/L 1 Raw Water 256 5.50 261 4.71 259 42.43 288 2 2 H2O2 Only 303 278 6.29 288 6.29 305 13 3 H2O2/UV 266 3.93 283 3.14 292 2.36 308 21 4 H2O2/UV/NH2Cl 289 4.71 281 2.36 441 14.93 336 25 5 UV Only 268 10.21 338 5.50 387 3.93 372 16 6 UV/NH2Cl 323 6.29 326 1.57 387 5.50 352 21 7 NaOCl Only 326 14.14 269 14.93 374 6.29 339 2 8 UV/NaOCl 322 4.71 282 11.79 289 5.50 308 1 9 NH2Cl Only 322 5.50 337 3.14 377 3.14 367 2 10 H2O2/UV/NaOCl 331 12.57 289 0.79 377 3.93 338 2 11 H2O2/NaOCl 326 7.07 333 7.86 398 12.57 365 5 12 H2O2/NH2Cl 324 8.64 279 6.29 392 4.71 357 1 130 Appendix D (continued)

PAGE 146

Table D 3: Size distribution of raw water particles 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mLm Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mLm 1 1 1.99 1.5 0.99 0.27 0.30 2156 2156 1.1E+03 1.4E+ 03 7.3E+02 7.2E+03 3.6E+03 3.34 2 2 2.99 2.5 0.99 0.40 0.17 347 347 1.8E+02 1.4E+02 7.1E+01 2.0E+03 1.0E+03 2.54 3 3 3.99 3.5 0.99 0.54 0.12 212 212 1.1E+02 6.1E+01 3.1E+01 1.7E+03 8.7E+02 2.33 4 4 4.99 4.5 0.99 0.65 0.10 89 89 4.5E+01 2.0E+01 1 .0E+01 9.2E+02 4.7E+02 1.95 5 5 5.99 5.5 0.99 0.74 0.08 92 92 4.7E+01 1.7E+01 8 .5E+00 1.2E+03 6.0E+02 1.97 6 6 6.99 6.5 0.99 0.81 0.07 52 52 2.6E+01 8.0E+00 4 .1E+00 7.8E+02 4.0E+02 1.72 7 7 7.99 7.5 0.99 0.87 0.06 48 48 2.4E+01 6.4E+00 3 .2E+00 8.3E+02 4.2E+02 1.68 8 8 8.99 8.5 0.99 0.93 0.05 24 24 1.2E+01 2.8E+00 1 .4E+00 4.7E+02 2.5E+02 1.38 9 9 9.99 9.5 0.99 0.98 0.05 28 28 1.4E+01 2.9E+00 1 .5E+00 6.1E+02 3.1E+02 1.45 10 10 10.99 10.5 0.99 1.02 0.04 8 8 4.1E+00 7.7E-01 3.9E-01 2.0E+02 10.E+01 0.91 11 11 11.99 11.5 0.99 1.06 0.04 7 7 3.6E+00 6.2E-01 3.1E-01 1.9E+02 9.7E+01 0.86 12 12 12.99 12.5 0.99 1.10 0.03 8 8 3.9E+00 6.1E-01 3.1E-01 2.2E+02 1.1E+02 0.88 13 13 13.99 13.5 0.99 1.13 0.03 16 16 7.9E+00 1.2E+ 00 5.9E-01 4.9E+02 2.5E+02 1.20 14 14 14.99 14.5 0.99 1.16 0.03 8 8 4.1E+00 5.6E-01 2.8E-01 2.7E+02 1.4E+02 0.91 15 15 15.99 15.5 0.99 1.19 0.03 8 8 4.1E+00 5.2E-01 2.6E-01 2.9E+02 1.5E+02 0.91 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.00E+0 0 0.00E+0 0 0.00E+0 0 0.00E+0 0 0.0E+00 131 Appendix D (continued)

PAGE 147

Table D 4: Size distribution of particles after hyd rogen peroxide treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mLm Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./m L-m 1 1 1.99 1.5 0.99 0.27 0.30 3204 3204 1.6E+03 2.1E+03 1.1E+03 1.1E+04 5.4E+03 3.5 2 2 2.99 2.5 0.99 0.40 0.17 266 266 1.4E+02 1.1E+02 5.4E+01 1.5E+03 7.8E+02 2.4 3 3 3.99 3.5 0.99 0.54 0.12 161 161 8.2E+01 4.6E+01 2.3E+01 1.3E+03 6.6E+02 2.2 4 4 4.99 4.5 0.99 0.65 0.10 111 111 5.7E+01 2.5E+01 1.3E+01 1.2E+03 5.9E+02 2.2 5 5 5.99 5.5 0.99 0.74 0.08 50 50 2.6E+01 9.1E+00 4 .6E+00 6.4E+02 3.3E+02 1.7 6 6 6.99 6.5 0.99 0.81 0.07 111 111 5.6E+01 1.7E+01 8.7E+00 1.7E+03 8.5E+02 2.1 7 7 7.99 7.5 0.99 0.87 0.06 60 60 3.1E+01 8.1E+00 4 .1E+00 1.1E+03 5.3E+02 1.8 8 8 8.99 8.5 0.99 0.93 0.05 70 70 3.6E+01 8.3E+00 4 .2E+00 1.4E+03 7.1E+02 1.9 9 9 9.99 9.5 0.99 0.98 0.05 9 9 4.9E+00 1.0E+00 5.2 E-01 2.1E+02 1.1E+02 9.9 10 10 10.99 10.5 0.99 1.02 0.04 20 20 1.0E+01 1.9E+ 00 9.8E-01 4.9E+02 2.5E+02 1.3 11 11 11.99 11.5 0.99 1.06 0.04 29 29 1.5E+01 2.6E+ 00 1.3E+00 7.9E+02 4.0E+02 1.5 12 12 12.99 12.5 0.99 1.10 0.03 19 19 1.0E+01 1.6E+ 00 8.1E-01 5.8E+02 2.9E+02 1.3 13 13 13.99 13.5 0.99 1.13 0.03 19 19 1.0E+01 1.5E+ 00 7.5E-01 6.2E+02 3.2E+02 1.3 14 14 14.99 14.5 0.99 1.16 0.03 10 10 5.2E+00 7.0E01 3.6E-01 3.4E+02 1.7E+02 1.0 15 15 15.99 15.5 0.99 1.19 0.03 10 10 5.2E+00 6.5E01 3.3E-01 3.7E+02 1.9E+02 1.0 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 132 Appendix D (continued)

PAGE 148

Table D 5: Size distribution of particles after hyd rogen peroxide-UV treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mLm Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mLm 1 1 1.99 1.5 0.99 0.17 0.30 264950 264950 1.4E+05 1 .8E+05 9.0E+04 8.9E+05 4.5E+05 5.4 2 2 2.99 2.5 0.99 0.40 0.17 28270 28270 1.4E+04 1.1 E+04 5.8E+03 1.6E+05 8.2E+04 4.5 3 3 3.99 3.5 0.99 0.54 0.12 23428 23428 1.2E+04 6.7 E+03 3.4E+03 1.9E+05 9.6E+04 4.4 4 4 4.99 4.5 0.99 0.65 0.10 4847 4847 2.5E+03 1.1E+ 03 5.5E+02 5.1E+04 2.6E+04 3.7 5 5 5.99 5.5 0.99 0.74 0.08 7271 7271 3.7E+03 1.3E+ 03 6.7E+02 9.3E+04 4.7E+04 3.9 6 6 6.99 6.5 0.99 0.81 0.07 9694 9694 4.9E+03 1.5E+ 03 7.6E+02 1.5E+05 7.4E+04 4.0 7 7 7.99 7.5 0.99 0.87 0.06 4039 4039 2.1E+03 5.4E+ 02 2.7E+02 7.0E+04 3.6E+04 3.6 8 8 8.99 8.5 0.99 0.93 0.05 6463 6463 3.3E+03 7.6E+ 02 3.9E+02 1.3E+05 6.5E+04 3.8 9 9 9.99 9.5 0.99 0.98 0.05 3231 3231 1.6E+03 3.4E+ 02 1.7E+02 7.1E+04 3.6E+04 3.5 10 10 10.99 10.5 0.99 1.02 0.04 1616 1616 8.2E+02 1 .5E+02 7.8E+01 3.9E+04 2.0E+04 3.2 11 11 11.99 11.5 0.99 1.06 0.04 807 807 4.1E+02 7.0 E+01 3.6E+01 2.2E+04 1.1E+04 2.9 12 12 12.99 12.5 0.99 1.10 0.03 807 807 4.1E+02 6.5E+0 1 3.3E+01 2.4E+04 1.2E+04 2.9 13 13 13.99 13.5 0.99 1.13 0.03 807 807 4.1E+02 6.0 E+01 3.0E+01 2.5E+04 1.3E+04 2.9 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 808 808 4.1E+02 5.2 E+01 2.7E+01 2.9E+04 1.5E+04 2.9 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 133 Appendix D (continued)

PAGE 149

Table D 6: Size distribution of particles after hyd rogen peroxide-UV-chlorine-ammonia treatment at amb ient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 347045 347045 1.8E+05 2 .3E+05 1.2E+05 1.2E+06 5.9E+05 5.5 2 2 2.99 2.5 0.99 0.40 0.17 19733 19733 1.0E+04 7.9 E+03 4.0E+03 1.1E+05 5.7E+04 4.3 3 3 3.99 3.5 0.99 0.54 0.12 13159 13159 6.7E+03 3.8 E+03 1.9E+03 1.1E+05 5.4E+04 4.1 4 4 4.99 4.5 0.99 0.65 0.10 9047 9047 4.6E+03 2.0E+ 03 1.0E+03 9.4E+04 4.8E+04 4.0 5 5 5.99 5.5 0.99 0.74 0.08 5757 5757 2.9E+03 1.1E+ 03 5.3E+02 7.3E+04 3.7E+04 3.8 6 6 6.99 6.5 0.99 0.81 0.07 3289 3289 1.7E+03 5.1E+ 02 2.6E+02 5.0E+04 2.5E+04 3.5 7 7 7.99 7.5 0.99 0.87 0.06 5757 5757 2.9E+03 7.7E+ 02 3.9E+02 1.0E+05 5.1E+04 3.8 8 8 8.99 8.5 0.99 0.93 0.05 4112 4112 2.1E+03 4.8E+ 02 2.5E+02 8.1E+04 4.1E+04 3.6 9 9 9.99 9.5 0.99 0.98 0.05 8224 8224 4.2E+03 8.7E+ 02 4.4E+02 1.8E+05 9.2E+04 3.9 10 10 10.99 10.5 0.99 1.02 0.04 1645 1645 8.4E+02 1 .6E+02 8.0E+01 4.0E+04 2.0E+04 3.2 11 11 11.99 11.5 0.99 1.06 0.04 4111 4111 2.1E+03 3 .6E+02 1.8E+02 1.1E+05 5.6E+04 3.6 12 12 12.99 12.5 0.99 1.10 0.03 822 822 4.2E+02 6.6E+0 1 3.3E+01 2.4E+04 1.2E+04 2.9 13 13 13.99 13.5 0.99 1.13 0.03 822 822 4.2E+02 6.1 E+01 3.1E+01 2.6E+04 1.3E+04 2.9 14 14 14.99 14.5 0.99 1.16 0.03 822 822 4.2E+02 5.7 E+01 2.9E+01 2.8E+04 1.4E+04 2.9 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 134 Appendix D (continued)

PAGE 150

Table D 7: Size distribution of particles after hyd rogen peroxide-UV-chlorine treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 322674 322674 1.6E+05 2 .2E+05 1.1E+05 1.1E+06 5.5E+05 5.5 2 2 2.99 2.5 0.99 0.40 0.17 16789 16789 8.5E+03 6.7 E+03 3.4E+03 9.6E+04 4.9E+04 4.2 3 3 3.99 3.5 0.99 0.54 0.12 15595 15595 7.9E+03 4.5 E+03 2.3E+03 1.3E+05 6.4E+04 4.2 4 4 4.99 4.5 0.99 0.65 0.10 2399 2399 1.2E+03 5.3E+ 02 2.7E+02 2.5E+04 1.3E+04 3.4 5 5 5.99 5.5 0.99 0.74 0.08 10797 10797 5.5E+03 2.0 E+03 10.0E+02 1.4E+05 7.0E+04 4.0 6 6 6.99 6.5 0.99 0.81 0.07 4798 4798 2.4E+03 7.4E+ 02 3.8E+02 7.2E+04 3.7E+04 3.7 7 7 7.99 7.5 0.99 0.87 0.06 1199 1199 6.1E+02 1.6E+ 02 8.1E+01 2.1E+04 1.1E+04 3.1 8 8 8.99 8.5 0.99 0.93 0.05 3599 3599 1.8E+03 4.2E+ 02 2.2E+02 7.1E+04 3.6E+04 3.6 9 9 9.99 9.5 0.99 0.98 0.05 1199 1199 6.1E+02 1.3E+ 02 6.4E+01 2.7E+04 1.3E+04 3.1 10 10 10.99 10.5 0.99 1.02 0.04 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 11 11 11.99 11.5 0.99 1.06 0.04 1199 1199 6.1E+02 1.0E +02 5.3E+01 3.2E+04 1.6E+04 3.1 12 12 12.99 12.5 0.99 1.10 0.03 1199 1199 6.1E+02 9 .6E+01 4.9E+01 3.5E+04 1.8E+04 3.1 13 13 13.99 13.5 0.99 1.13 0.03 1199 1199 6.1E+02 8 .9E+01 4.5E+01 3.8E+04 1.9E+04 3.1 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 135 Appendix D (continued)

PAGE 151

Table D 8: Size distribution of particles after hyd rogen peroxide-chlorine treatment at ambient pH 8/1 6/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 296270 296270 1.5E+05 2 .0E+05 1.0E+05 9.9E+05 5.0E+05 5.5 2 2 2.99 2.5 0.99 0.40 0.17 18732 18732 9.5E+03 7.5 E+03 3.8E+03 1.1E+05 5.5E+04 4.3 3 3 3.99 3.5 0.99 0.54 0.12 8197 8197 4.2E+03 2.4E+ 03 1.2E+03 6.6E+04 3.4E+04 3.9 4 4 4.99 4.5 0.99 0.65 0.10 10541 10541 5.4E+03 2.3 E+03 1.2E+03 1.1E+05 5.6E+04 4.0 5 5 5.99 5.5 0.99 0.74 0.08 4684 4684 2.4E+03 8.5E+ 02 4.3E+02 6.0E+04 3.0E+04 3.7 6 6 6.99 6.5 0.99 0.81 0.07 1171 1171 6.0E+02 1.8E+ 02 9.2E+01 1.8E+04 9.0E+03 3.1 7 7 7.99 7.5 0.99 0.87 0.06 3513 3513 1.8E+03 4.7E+ 02 2.4E+02 6.1E+04 3.1E+04 3.6 8 8 8.99 8.5 0.99 0.93 0.05 4684 4684 2.4E+03 5.5E+ 02 2.8E+02 9.2E+04 4.7E+04 3.7 9 9 9.99 9.5 0.99 0.98 0.05 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 10 10 10.99 10.5 0.99 1.02 0.04 2342 2342 1.2E+03 2 .2E+02 1.1E+02 5.7E+04 2.9E+04 11 11 11.99 11.5 0.99 1.06 0.04 2341 2341 1.2E+03 2 .0E+02 1.0E+02 6.3E+04 3.2E+04 3.4 12 12 12.99 12.5 0.99 1.10 0.03 0 0 0.0E+00 0.0E+00 0. 0E+00 0.0E+00 0.0E+00 13 13 13.99 13.5 0.99 1.13 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 136 Appendix D (continued)

PAGE 152

Table D 9: Size distribution of particles after hyd rogen peroxide-chlorine treatment at ambient pH 8/1 6/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 159710 159710 8.1E+04 1 .1E+05 5.4E+04 5.3E+05 2.7E+05 5.2 2 2 2.99 2.5 0.99 0.40 0.17 3842 3842 2.0E+03 1.5E+ 03 7.8E+02 2.2E+04 1.1E+04 3.6 3 3 3.99 3.5 0.99 0.54 0.12 3849 3849 2.0E+03 1.1E+ 03 5.6E+02 3.1E+04 1.6E+04 3.6 4 4 4.99 4.5 0.99 0.65 0.10 1925 1925 9.8E+02 4.3E+ 02 2.2E+02 2.0E+04 1.0E+04 3.3 5 5 5.99 5.5 0.99 0.74 0.08 1924 1924 9.8E+02 3.5E+ 02 1.8E+02 2.5E+04 1.3E+04 3.3 6 6 6.99 6.5 0.99 0.81 0.07 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 7 7 7.99 7.5 0.99 0.87 0.06 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 8 8 8.99 8.5 0.99 0.93 0.05 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 9 9 9.99 9.5 0.99 0.98 0.05 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 10 10 10.99 10.5 0.99 1.02 0.04 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 11 11 11.99 11.5 0.99 1.06 0.04 0 0 0.0E+00 0.0E+00 0. 0E+00 0.0E+00 0.0E+00 12 12 12.99 12.5 0.99 1.10 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 13 13 13.99 13.5 0.99 1.13 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 137 Appendix D (continued)

PAGE 153

Table D 10: Size distribution of particles after UV treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 734 734 3.7E+02 4.9E+02 2.5E+02 2.5E+03 1.3E+03 2.9 2 2 2.99 2.5 0.99 0.40 0.17 53 53 2.7E+01 2.1E+01 1 .1E+01 3.0E+02 1.5E+02 1.7 3 3 3.99 3.5 0.99 0.54 0.12 21 21 1.1E+01 6.0E+00 3 .1E+00 1.7E+02 8.6E+01 1.3 4 4 4.99 4.5 0.99 0.65 0.10 7 7 3.5E+00 1.5E+00 7.8 E-01 7.2E+01 3.7E+01 0.8 5 5 5.99 5.5 0.99 0.74 0.08 13 13 6.6E+00 2.4E+00 1 .2E+00 1.7E+02 8.4E+01 1.1 6 6 6.99 6.5 0.99 0.81 0.07 6 6 2.9E+00 8.9E-01 4.5 E-01 8.7E+01 4.4E+01 0.8 7 7 7.99 7.5 0.99 0.87 0.06 3 3 1.4E+00 3.7E-01 1.9 E-01 4.8E+01 2.5E+01 0.5 8 8 8.99 8.5 0.99 0.93 0.05 3 3 1.4E+00 3.3E-01 1.7 E-01 5.5E+01 2.8E+01 0.5 9 9 9.99 9.5 0.99 0.98 0.05 1 1 4.7E-01 9.8E-02 5.0 E-02 2.0E+01 1.0E+01 10 10 10.99 10.5 0.99 1.02 0.04 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 11 11 11.99 11.5 0.99 1.06 0.04 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 12 12 12.99 12.5 0.99 1.10 0.03 0 0 0.0E+00 0.0E+00 0. 0E+00 0.0E+00 0.0E+00 13 13 13.99 13.5 0.99 1.13 0.03 1 1 4.7E-01 6.9E-02 3.5E-02 2.9E+01 1.5E+01 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 1 1 4.7E-01 5.6E-02 2.9E-02 3.6E+01 1.8E+01 138 Appendix D (continued)

PAGE 154

Table D 11: Size distribution of particles after UV -chlorine treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 204652 204652 1.0E+05 1 .4E+05 7.0E+04 6.9E+05 3.5E+05 5.3 2 2 2.99 2.5 0.99 0.40 0.17 22384 22384 1.1E+04 9.0 E+03 4.6E+03 1.3E+05 6.5E+04 4.4 3 3 3.99 3.5 0.99 0.54 0.12 10659 10659 5.4E+03 3.1 E+03 1.6E+03 8.6E+04 4.4E+04 4.0 4 4 4.99 4.5 0.99 0.65 0.10 12791 12791 6.5E+03 2.9 E+03 1.45E+03 1.3E+05 6.8E+04 4.1 5 5 5.99 5.5 0.99 0.74 0.08 7461 7461 3.8E+03 1.4E+ 03 6.9E+02 9.5E+04 4.8E+04 3.9 6 6 6.99 6.5 0.99 0.81 0.07 3198 3198 1.6E+03 4.9E+ 02 2.5E+02 4.8E+04 2.5E+04 3.5 7 7 7.99 7.5 0.99 0.87 0.06 3198 3198 1.6E+03 4.3E+ 02 2.2E+02 5.6E+04 2.8E+04 3.5 8 8 8.99 8.5 0.99 0.93 0.05 6395 6395 3.3E+03 7.5E+ 02 3.8E+02 1.3E+05 6.4E+04 3.8 9 9 9.99 9.5 0.99 0.98 0.05 2132 2132 1.1E+03 2.3E+ 02 1.1E+02 4.7E+04 2.4E+04 3.3 10 10 10.99 10.5 0.99 1.02 0.04 2132 2132 1.1E+03 2 .0E+02 1.0E+02 5.2E+04 2.6E+04 11 11 11.99 11.5 0.99 1.06 0.04 1066 1066 5.4E+02 9.3E +01 4.7E+01 2.9E+04 1.5E+04 3.0 12 12 12.99 12.5 0.99 1.10 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 13 13 13.99 13.5 0.99 1.13 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 139 Appendix D (continued)

PAGE 155

Table D 12: Size distribution of particles after UV -chlorine-ammonia treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 61959 61959 3.2E+04 4.1 E+04 2.1E+04 2.1E+05 1.1E+05 4.8 2 2 2.99 2.5 0.99 0.40 0.17 875 875 4.4E+02 3.5E+02 1.8E+02 5.0E+03 2.5E+03 3.0 3 3 3.99 3.5 0.99 0.54 0.12 623 623 3.2E+02 1.8E+02 9.1E+01 5.0E+03 2.6E+03 2.8 4 4 4.99 4.5 0.99 0.65 0.10 498 498 2.5E+02 1.1E+02 5.6E+01 5.2E+03 2.6E+03 2.7 5 5 5.99 5.5 0.99 0.74 0.08 250 250 1.3E+02 4.6E+01 2.3E+01 3.2E+03 1.6E+03 2.4 6 6 6.99 6.5 0.99 0.81 0.07 249 249 1.3E+02 3.8E+01 2.0E+01 3.8E+03 1.9E+03 2.4 7 7 7.99 7.5 0.99 0.87 0.06 500 500 2.5E+02 6.7E+01 3 .4E+01 8.7E+03 4.4E+03 2.7 8 8 8.99 8.5 0.99 0.93 0.05 625 625 3.2E+02 7.4E+01 3.7E+01 1.2E+04 6.3E+03 2.8 9 9 9.99 9.5 0.99 0.98 0.05 375 375 1.9E+02 4.0E+01 2.0E+01 8.3E+03 4.2E+03 2.6 10 10 10.99 10.5 0.99 1.02 0.04 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 11 11 11.99 11.5 0.99 1.06 0.04 250 250 1.3E+02 2.2E+0 1 1.1E+01 6.7E+03 3.4E+03 2.4 12 12 12.99 12.5 0.99 1.10 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 13 13 13.99 13.5 0.99 1.13 0.03 125 125 6.4E+01 9.3 E+00 4.7E+00 3.9E+03 2.0E+03 2.1 14 14 14.99 14.5 0.99 1.16 0.03 250 250 1.3E+02 1.7 E+01 8.8E+00 8.4E+03 4.3E+03 15 15 15.99 15.5 0.99 1.19 0.03 250 250 1.3E+02 1.6 E+01 8.2E+00 9.0E+03 4.6E+03 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 140 Appendix D (continued)

PAGE 156

Table D 13: Size distribution of particles after ch lorine treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 12054 12054 6.1E+03 8.1 E+03 4.1E+03 4.0E+04 2.1E+04 4.1 2 2 2.99 2.5 0.99 0.40 0.17 214 214 1.1E+02 8.6E+01 4.4E+01 1.2E+03 6.2E+02 2.3 3 3 3.99 3.5 0.99 0.54 0.12 51 51 2.6E+01 1.5E+01 7 .5E+00 4.2E+02 2.1E+02 1.7 4 4 4.99 4.5 0.99 0.65 0.10 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 5 5 5.99 5.5 0.99 0.74 0.08 107 107 5.5E+01 2.0E+01 9.9E+00 1.4E+03 7.0E+02 2.0 6 6 6.99 6.5 0.99 0.81 0.07 107 107 5.4E+01 1.6E+01 8.3E+00 1.6E+03 8.2E+02 2.0 7 7 7.99 7.5 0.99 0.87 0.06 54 54 2.7E+01 7.2E+00 3 .6E+00 9.3E+02 4.7E+02 1.7 8 8 8.99 8.5 0.99 0.93 0.05 54 54 2.7E+01 6.3E+00 3 .2E+00 1.1E+03 5.4E+02 1.7 9 9 9.99 9.5 0.99 0.98 0.05 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 10 10 10.99 10.5 0.99 1.02 0.04 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 11 11 11.99 11.5 0.99 1.06 0.04 54 54 2.7E+01 4.7E+00 2.4E+00 1.4E+03 7.3E+02 1.7 12 12 12.99 12.5 0.99 1.10 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 13 13 13.99 13.5 0.99 1.13 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 141 Appendix D (continued)

PAGE 157

Table D 14: Size distribution of particles after ch lorine-ammonia treatment at ambient pH 8/16/2005 Channel No. Lower Limit dp m Upper Limit dp m Mean Diam. dpi m dpi m log dpi dp in m log dpi Corrected Count Number conc. Ni, No./mL Volume Conc. Vi m3/mL Ni/dpi No./mL-m Vi/dpi m3/mLm Ni/ log dpi No./mL Vi/ log dpi m3/mL log Ni/ dpi in No./mL-m 1 1 1.99 1.5 0.99 0.17 0.30 9081 9081 4.6E+03 6.1E+ 03 3.1E+03 3.0E+04 1.5E+04 4.0 2 2 2.99 2.5 0.99 0.40 0.17 222 222 1.1E+02 8.9E+01 4.5E+01 1.3E+03 6.5E+02 2.4 3 3 3.99 3.5 0.99 0.54 0.12 101 101 5.2E+01 2.9E+01 1.5E+01 8.2E+02 4.2E+02 2.0 4 4 4.99 4.5 0.99 0.65 0.10 28 28 1.4E+01 6.3E+00 3 .2E+00 2.9E+02 1.5E+02 1.5 5 5 5.99 5.5 0.99 0.74 0.08 74 74 3.8E+01 1.3E+01 6 .8E+00 9.4E+02 4.8E+02 1.9 6 6 6.99 6.5 0.99 0.81 0.07 29 29 1.5E+01 4.4E+00 2 .3E+00 4.4E+02 2.2E+02 1.5 7 7 7.99 7.5 0.99 0.87 0.06 0 0 0.0E+00 0.0E+00 0.0 E+00 0.0E+00 0.0E+00 8 8 8.99 8.5 0.99 0.93 0.05 15 15 7.5E+00 1.7E+00 8.4 E-01 2.9E+02 1.5E+02 1.2 9 9 9.99 9.5 0.99 0.98 0.05 74 74 3.8E+01 7.8E+00 4 .0E+00 1.6E+03 8.3E+02 1.9 10 10 10.99 10.5 0.99 1.02 0.04 15 15 7.5E+00 1.4E+ 00 7.2E-01 3.6E+02 1.8E+02 11 11 11.99 11.5 0.99 1.06 0.04 30 30 1.5E+01 2.6E+ 00 1.3E+00 7.9E+02 4.0E+02 1.5 12 12 12.99 12.5 0.99 1.10 0.03 30 30 1.5E+01 2.4E+ 00 1.2E+00 8.6E+02 4.4E+02 1.5 13 13 13.99 13.5 0.99 1.13 0.03 15 15 7.5E+00 1.1E+ 00 5.6E-01 4.6E+02 2.4E+02 1.2 14 14 14.99 14.5 0.99 1.16 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 15 15 15.99 15.5 0.99 1.19 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 16 16 16.99 16.5 0.99 1.22 0.03 0 0 0.0E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 142 Appendix D (continued)

PAGE 158

Table D 15: Size distribution of particles at eleva ted pH 8/23/2005 Corrected Count for Treatments Lower Limit dp um Upper Limit dp um Raw Water Hydrogen Peroxide Hydrogen Peroxide-UV Hydrogen Peroxide-UV-Chloramine Hydrogen Peroxide-UV-Chlorine Hydrogen Peroxide-Chlorine Hydrogen Peroxide-Chloramine UV UV-Chlorine UV-Chloramine Chlorine Chloramine 1 1.99 3579 3536 1230 5066 18708 2740 6446 13233 31534 16868 1719 30 83 2 2.99 382 249 229 395 1471 289 589 1354 632 466 10 6 204 3 3.99 239 158 131 257 276 104 515 1024 505 311 77 89 4 4.99 111 65 49 83 276 98 230 396 168 249 49 62 5 5.99 95 19 36 129 735 74 166 396 84 124 14 98 6 6.99 72 46 42 110 368 86 120 165 211 93 35 27 7 7.99 24 28 38 55 0 6 83 0 211 155 0 53 8 8.99 16 19 13 83 92 18 74 66 84 31 7 71 9 9.99 24 9 13 64 0 25 18 66 84 62 7 9 10 10.99 8 9 13 55 0 6 74 0 0 31 0 9 11 11.99 8 9 6 18 0 6 46 66 0 0 7 27 12 12.99 0 0 6 9 0 0 9 0 0 0 0 0 13 13.99 0 0 2 9 92 0 0 0 0 0 0 18 14 14.99 8 0 4 18 0 0 0 0 0 31 0 0 15 15.99 0 0 9 73 0 18 9 33 0 31 0 18 16 16.99 0 0 6 28 0 0 0 0 42 0 0 0 143 Appendix D (continued)

PAGE 159

Table D 16: Size distribution of particles at ambie nt pH 9/5/2005 Corrected Count for Treatments Lower Limit dp um Upper Limit dp um Raw Water Hydrogen Peroxide Hydroge n Peroxide -UV Hydrogen Peroxide-UV-Chloramine Hydrogen Peroxide-UV-Chlorine Hydrogen Peroxide-Chlorine Hydrogen Peroxide-Chloramine UV UV-Chlorine UV-Chloramine Chlorine Chloramine 1 1.99 593 6701 8352 184 19623 22225 11100 9864 12843 28232 25353 4 6300 2 2.99 459 958 793 23 1309 2060 3089 806 917 2992 2 187 2004 3 3.99 347 640 243 15 2156 3092 830 1209 459 2995 1 537 801 4 4.99 139 292 59 9 1002 1619 361 537 184 2111 1181 401 5 5.99 125 167 120 9 1079 1398 605 739 275 2026 165 5 1002 6 6.99 74 157 61 9 1079 1031 365 201 92 1499 887 80 1 7 7.99 84 83 0 7 462 734 243 336 92 2292 1004 400 8 8.99 50 94 0 3 617 1031 0 269 275 2204 531 400 9 9.99 36 42 60 2 463 589 0 336 0 1675 177 200 10 10.99 40 21 0 5 848 368 0 201 0 1410 0 100 11 11.99 34 35 61 2 617 589 0 134 184 882 58 100 12 12.99 17 35 0 1 231 221 0 0 92 353 0 0 13 13.99 15 30 0 1 231 295 0 201 184 264 59 0 14 14.99 13 7 0 1 0 74 0 67 92 88 59 0 15 15.99 20 5 0 0 308 295 0 0 0 617 0 0 16 16.99 4 0 0 1 77 74 0 0 184 88 0 100 144 Appendix D (continued)

PAGE 160

Table D 17: Size distribution of particles at eleva ted pH 9/10/2005 Corrected Count for Treatments Lower Limit dp um Upper Limit dp um Raw Water Hydrogen Peroxide Hydrogen PeroxideUV Hydrogen Peroxide-UV-Chloramine Hydrogen Peroxide-UV-Chlorine UV-Chloramine Chlorine Chloramine 1 1.99 6265 3680 2564 10260 25895 21651 25575 30285 2 2.99 797 331 612 144 1827 3474.8 4323.74 2484.66 3 3.99 658 211 175 72 2108 2806.57 4779.31 1774.76 4 4.99 312 151 29 72 552 1603.75 2729.22 532.427 5 5.99 312 301 29 96 281 2004.69 2155.53 532.427 6 6.99 243 30 29 72 281 1202.82 1594.51 177.476 7 7.99 35 30 58 24 141 801.877 1809.62 0 8 8.99 104 91 29 48 422 1069.17 1134.71 354.951 9 9.99 35 91 0 24 0 267.292 1134.71 0 10 10.99 0 91 0 0 281 801.877 1138.94 177.476 11 11.99 35 60 0 0 0 267.292 911.15 177.476 12 12.99 0 0 0 24 0 0 113.894 0 13 13.99 0 0 0 0 0 133.646 227.788 0 14 14.99 0 0 0 24 0 0 227.788 0 15 15.99 35 0 0 0 141 267.292 569.469 0 16 16.99 0 0 0 24 0 0 341.681 0 145 Appendix D (continued)


xml version 1.0 encoding UTF-8 standalone no
record xmlns http:www.loc.govMARC21slim xmlns:xsi http:www.w3.org2001XMLSchema-instance xsi:schemaLocation http:www.loc.govstandardsmarcxmlschemaMARC21slim.xsd
leader nam Ka
controlfield tag 001 001913675
003 fts
005 20071015133609.0
006 m||||e|||d||||||||
007 cr mnu|||uuuuu
008 071015s2005 flu sbm 000 0 eng d
datafield ind1 8 ind2 024
subfield code a E14-SFE0001390
040
FHM
c FHM
035
(OCoLC)174144064
049
FHMM
090
TA170 (ONLINE)
1 100
Minnis, Rochelle J.
0 245
Comparison of the use of single and multiple oxidants on the generation of particulate matter in water distribution systems derived from groundwater sources containing hydrogen sulfide and dissolved organics
h [electronic resource] /
by Rochelle J. Minnis.
260
[Tampa, Fla] :
b University of South Florida,
2005.
3 520
ABSTRACT: Due to increasingly stringent regulations, concerns about disinfection byproduct formation, and the need for improved control of distribution system water quality, there has been a shift towards the use of alternative disinfectants and oxidants in the production of drinking water. Technologies that modify water chemistry, such as hydrogen peroxide, UV irradiation, chlorine and/or chloramines may result in the generation of mineral and organic precipitates. Turbidity provides an indirect measure of the presence of particles by evaluating the light scattering properties of water. Turbidity levels are currently not monitored or regulated in treated groundwater. An important water quality parameter that influences groundwater quality is hydrogen sulfide. The control of sulfides in groundwater is of importance because its presence can cause odor and taste complaints, corrosion of pipes and other plumbing fixtures, and black-water problems in distribution systems (Levine et. ^al, 2004). In addition, sulfides can impose a significant oxidant demand and possibly interfere with disinfection treatments. Characteristics of particles from untreated and treated groundwater were tested as part of a field study to evaluate alternative wellhead treatment approaches for controlling hydrogen sulfide. A 1 gallon per minute (gpm) pilot-plant was used to test several groundwater treatment scenarios. The chemicals tested included chlorine, monochloramine, and hydrogen peroxide either alone or in tandem. Photochemical oxidation was evaluated using UV and advanced oxidation was evaluated using hydrogen peroxide coupled with UV. Testing was conducted either on water pumped directly from the well at ambient (7.0-7.5), or pretreated with caustic soda to evaluate the impact of elevated pH (8.2) conditions. The formation of particles was quantified using turbidity, solids (total, dissolved and suspended), and particle counts before and after oxidation. The particulate matt er was characterized using a particle size analyzer in conjunction with scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). Treatment systems that rely on in-line treatment lack mechanisms for particle removal, therefore particles generated through treatment are introduced into the distribution system. It is evident from this project that treatment systems should be optimized to prevent particle formation.
502
Thesis (M.S.)--University of South Florida, 2005.
504
Includes bibliographical references.
516
Text (Electronic thesis) in PDF format.
538
System requirements: World Wide Web browser and PDF reader.
Mode of access: World Wide Web.
500
Title from PDF of title page.
Document formatted into pages; contains 145 pages.
590
Adviser: Audrey D. Levine, Ph.D.
653
Turbidity.
UV irradiation.
Chlorine.
Chloramine.
Particle count.
690
Dissertations, Academic
z USF
x Environmental Engineering
Masters.
773
t USF Electronic Theses and Dissertations.
4 856
u http://digital.lib.usf.edu/?e14.1390