WRF Webcast Biofilter Conversion Guidance Manual

No part of this presentation may be copied, reproduced, or otherwise utilized without permission. WRF Webcast Biofilter Conversion Guidance Manual March 28, 2017

Biofiltration: Defining Benefits and Developing Utility Guidance By 2017, determine biofiltration effectiveness at removing multiple contaminants, define benefits and communicate to key stakeholders, and provide utility guidance on optimizing biofiltration.

Focus Area Projects Project Title 4459 Development of a Biofiltration Knowledge Base 4496 Converting Conventional Filters to Biofilters 4555 Optimizing Biofiltration for Various Source Water Quality 4559 4620 Simultaneous Removal of Multiple Chemical Contaminants Using Biofiltration Practical Monitoring Tools for the Biological Processes in Biofiltration 4719 Biofiltration Guidance Manual

Biofilter Conversion Guidance Manual WRF Project #4496

Speakers Jess Brown, PhD, PE Carollo Engineers Giridhar Upadhyaya, PhD, PE Carollo Engineers Ashley Evans, PE Arcadis

Agenda Motivation, Objectives & Approach Survey Results Case Studies How suitable is biofiltration for my facility and what are recommended mitigation strategies? Assessment Tool Guidance Manual

Motivation, Objectives & Approach

Coagulant Polymer Chlorine Chlorine Fluoride Ammonia Sodium Hydroxide Conventional to Biological Filtration Raw Water Rapid Mix Flocculation / Sedimentation Filtration Clearwell Distribution System Conventional Water Treatment

Coagulant Polymer Chlorine (Backup Only) Chlorine Fluoride Ammonia Sodium Hydroxide Conventional to Biological Filtration Raw Water Rapid Mix Flocculation / Sedimentation Biofiltration Clearwell Distribution System Conventional Water Treatment Biofiltration Operation

Ozone Coagulant Polymer Chlorine (Backup Only) Ozone Chlorine Fluoride Ammonia Sodium Hydroxide Conventional to Biological Filtration Raw Water Ozone Rapid Mix Flocculation / Sedimentation Ozone Biofiltration Clearwell Distribution System Conventional Water Treatment Biofiltration Operation Optional Ozone Addition

Project Driver Multiple factors may control bioacclimation and biofilter performance Construction Type Based on WRF 4459: Biofiltration Knowledge Base No industry guidance for testing, designing, and implementing this transition Success factors? Optimal operating conditions? Case studies? Issues and challenges? Mitigation strategies? New Construction 48% Retrofit 52% Source: WRF Project 4459

Overall Project Objective To catalog and summarize current biofilter conversion practices with a focus on: Planning Evaluation (testing) Conversion implementation Operation and monitoring Process optimization Developed Conversion Assessment Tool Conversion Guidance Manual

Research Approach Conversion Survey Lit Review Case Studies

Research Approach Conversion Survey Lit Review Case Studies Project Team Experiences

Research Approach Conversion Survey Lit Review Case Studies Project Team Experiences

Survey Results

Utility Survey Design and Participants Facility Information Water Quality Information Driver for Biofiltration Evaluation Phase Planning Activities Implementation Experience Lessons Learned 17 full-scale facilities! 23 to 750 MGD 2 to >17 years 61% were retrofitted from existing conventional filters 41% river, 24% reservoir & 35% blended source waters 70 questions in 7 categories!

Design Capacity (MGD) Participants Represented a Combined 2,286 MGD in Biofilter Capacity 800 750 Biofiltration Facility Design Capacity 700 600 500 400 300 280 240 220 200 150 120 110 75 59 54 50 40 30 30 30 25 23 100 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Facilities

Years of Operation 18 16 Participants Represented Over 140 Years of Combined Biofilter Operational Experience 17 Years of Biofilter Operation 14 12 10 8 11 10+ 10+ 10+ 10+ 10+ 10+ 9 9 8 7 7 6 4 2 4 3 3 2 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Facilities

Participants Included Facilities with a Range of Biofiltration Design & Operating Schemes Treatment Scheme Backwash Scheme GAC/S - Chlorine Residual 18% GAC or GAC/S - No Ozone 18% GAC or GAC/S - Ozone 17% A/S - Ozone 47% Legend: GAC: Granular Activated Carbon S: Sand A: Anthracite Chloraminated Backwash 9% Chlorinated Backwash 27% Non- Chlorinated Backwash 64%

Most Utilities Targeted More than One Treatment Objective with Biofiltration Primary Drivers for Conversion Highlighted in Purple Number of Facilities 0 2 4 6 8 10 12 14 Organics Removal (TOC, AOC, etc.) Costs / Media Change-out Frequency Disinfection Byproducts Precursor Removal Taste and Odor Removal Increased Loading Rate Metals (Fe/Mn) Removal Distribution System Water Quality Stability Chlorite Removal In Use at Other Plants

Key Themes were Identified for Each Stage of the Conversion Process Evaluation Few infrastructure evaluations Pilot scale or full-scale evaluations Optimization strategies unavailable Limited knowledge transfer Planning No implementation plans No mitigation strategies prior to start-up No biofiltration process training Monitoring parameters varied Implementation Timing based on other factors (e.g., media replacement or construction schedule) No biofiltration process optimization Costs not tracked

No. of Facilities Most Facilities Completed Either a Pilot or Full-Scale Evaluation Prior to Conversion 7 6 5 4 3 2 1 0 Bench & Pilot Pilot Pilot & Full-Scale Demo / Full- Scale None

Most Participating Utilities Converted to Biofiltration with Minimal Planning Related to the Biofiltration Process Implementation Plans None Construction Start- Up Document Extensive 13 3 1 Biofiltration Process Training None 16 Extensive 1 Monitoring Plans A Few New Parameters Several New Parameters Extensive 12 4 1 Number of Facilities

Implementation Experiences Varied Across the Participating Utilities Utility A Utility B Utility C Utility D Full-Scale Challenges? Yes Some No Yes Continuous No Tried Optimization? No No Yes Not Successful Yes Not Successful Summary Still Deciding No Issues Continuous Issues Significant Planning

Lessons Learned: Mitigation Strategies were Generally Not Developed until Challenges Occurred Algae Control Nutrient & Headloss Monitoring Manganese Control Copper sulfate added pre-settling when temp >18 C Monitored headloss to signal underdrain fouling Monitored for free ammonia and phosphorus Switched from ferric to alum coagulant Replaced filter media

Case Studies

Aspects Evaluated in Case Studies Performance of biofilters versus conventional filters Effects of media type Effects of media age Mn release during filter conversion Data compared included: Design and operating characteristics Water quality Microbial parameters Morsang WTP, France

Key Findings from the Case Studies Hydraulic and water treatment performance similar before and after conversion Media age did not impact performance Faster acclimation on GAC compared to anthracite Legacy Mn release immediately after conversion mitigated through: GAC media Performance enhancement strategies

Conventional Filtration VS Biofiltration

Ferric Chloride Aluminum Sulfate X Chlorine Ozone X Chlorine Ammonia Chlorine Conventional Filtration VS Biofiltration Media Age: 10 years Bottom Layer: 8 inches sand Top Layer: 26 inches anthracite Raw Water Rapid Mix Flocculation / Sedimentation Ozone Contactor Biofilters Filters Clearwell Distribution System Parameters Evaluated - Hydraulic (Runtime, Headloss) - TOC and turbidity removal Provision for Chlorinated Backwash

Clean-bed Headloss (ft) N = 88 N = 2785 Loading Rate (gpm/ft 2 ) N = 361 N = 359 Filter Runtime (hour) N = 361 N = 359 Similar Hydraulic Performance Before and After Conversion 5.0 4.0 3.0 2.0 1.0 0.0 1 2 Before After 30 20 10 0 1 2 Before After 1.5 1.0 0.5 0.0 1 2 Before After Based on Median Values

Effluent TOC (mg/l) N = 53 N = 49 Influent Turbidity (NTU) N = 4322 N = 4293 Effluent Turbidity (NTU) N = 4316 N = 4286 Similar Effluent Turbidity and TOC Before and After Conversion 1.0 0.8 0.6 0.4 0.2 0.0 1 2 Before After 0.10 0.08 0.06 0.04 0.02 0.00 1 2 Before After Filter/Biofilter Influent TOC data were not available 2.50 2.00 1.50 1.00 0.50 0.00 1 2 Before After Based on Median Values

Effects of Media Type

Does Media Type Affect Biofilter Performance? Media age: 14 years Filter No. Media Type Chlorinated Influent? Filter 1 Anthracite/sand Yes Filter 4 Anthracite/sand No Filter 6 GAC/sand No Parameters Evaluated - Hydraulic (Run length, Headloss) - Water quality (Turbidity and aldehyde removal, Mn leaching)

Headloss was Similar Before and After Conversion to Biofiltration Max 75 th percentile Median 25 th percentile Min

Lower Run Length Observed in GAC System After Conversion to Biofiltration

Similar Terminal Turbidity Before and After Conversion to Biofiltration

Aldehyde (µg/l) Faster Biological Acclimation Observed in the GAC Biofilter Compared to the Anthracite Biofilters 90 80 70 60 50 40 30 20 10 0 Conversion Influent 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Aldehyde (µg/l) Faster Biological Acclimation Observed in the GAC Biofilter Compared to the Anthracite Biofilters 90 80 70 60 50 40 30 20 10 0 Conversion Influent Cl2 Anth 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Aldehyde (µg/l) Faster Biological Acclimation Observed in the GAC Biofilter Compared to the Anthracite Biofilters 90 80 70 60 50 40 30 20 10 0 Conversion Influent Cl2 Anth No Cl2 GAC 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Aldehyde (µg/l) Faster Biological Acclimation Observed in the GAC Biofilter Compared to the Anthracite Biofilters 90 80 70 60 50 40 30 20 10 0 Conversion Influent Cl2 Anth No Cl2 GAC No Cl2 Anth 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Total Mn (mg/l) Legacy Mn was not Released from the GAC Biofilter during Filter Conversion 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 Cl2 Anth 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Total Mn (mg/l) Legacy Mn was not Released from the GAC Biofilter during Filter Conversion 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 Cl2 Anth No Cl2 GAC 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Total Mn (mg/l) Legacy Mn was not Released from the GAC Biofilter during Filter Conversion 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 Cl2 Anth No Cl2 GAC No Cl2 Anth 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Total Mn (mg/l) Legacy Mn was not Released from the GAC Biofilter during Filter Conversion 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 Similar trend for dissolved Mn Dissolved Mn was 35 to 100 percent of total Mn Cl2 Anth No Cl2 GAC No Cl2 Anth 0.00 0 25 50 75 100 125 150 175 200 225 250 275 300 Time (days)

Can Mn Release be Controlled/Minimized during Filter Conversion?

X Chlorine Can Mn Release be Controlled/Minimized During Conversion? Filter No. Media Type Filter Type Filter 19 Anthracite Conventional Filter 21 Anthracite Biofilter Filter 24 Anthracite Engineered Biofilter (ph 7.8, 0.02 mg/l P)

Dissolved Manganese (mg/l) 0.11 0.10 0.09 Performance Enhancement Strategies Helped Minimize Mn Release Conversion Filter Influent 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 8/9 8/25 9/10 9/26 10/12 10/28 11/13 11/29 12/15 12/31

Dissolved Manganese (mg/l) 0.11 0.10 Performance Enhancement Strategies Helped Minimize Mn Release Conversion Filter Influent 0.09 Filter 19 - Conv. Filter 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 8/9 8/25 9/10 9/26 10/12 10/28 11/13 11/29 12/15 12/31

Dissolved Manganese (mg/l) 0.11 0.10 0.09 0.08 Performance Enhancement Strategies Helped Minimize Mn Release Conversion Filter Influent Filter 19 - Conv. Filter Filter 21 - Biofilter 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 8/9 8/25 9/10 9/26 10/12 10/28 11/13 11/29 12/15 12/31

Dissolved Manganese (mg/l) 0.11 0.10 0.09 0.08 Performance Enhancement Strategies Helped Minimize Mn Release Conversion Filter Influent Filter 19 - Conv. Filter Filter 21 - Biofilter Filter 24 - Eng. Biofilter 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 8/9 8/25 9/10 9/26 10/12 10/28 11/13 11/29 12/15 12/31

Dissolved Mn Removal (mg/l) 0.10 0.08 0.06 Performance Enhancement Strategies Helped Minimize Mn Release Conversion Filter 19 - Conv. Filter 0.04 0.02 0.00-0.02-0.04-0.06 8/9 8/25 9/10 9/26 10/12 10/28 11/13 11/29 12/15 12/31

Dissolved Mn Removal (mg/l) 0.10 0.08 0.06 0.04 Performance Enhancement Strategies Helped Minimize Mn Release Conversion Filter 19 - Conv. Filter Filter 21 - Biofilter 0.02 0.00-0.02-0.04-0.06 8/9 8/25 9/10 9/26 10/12 10/28 11/13 11/29 12/15 12/31

Dissolved Mn Removal (mg/l) 0.10 0.08 0.06 0.04 Performance Enhancement Strategies Helped Minimize Mn Release Conversion Filter 19 - Conv. Filter Filter 21 - Biofilter Filter 24 - Eng. Biofilter 0.02 0.00-0.02-0.04-0.06 8/9 8/25 9/10 9/26 10/12 10/28 11/13 11/29 12/15 12/31

Conversion Assessment Tool

Development of the Assessment Tool was a Collaborative Process Participants: Project Team Utilities & PAC Utility Survey of Full-Scale Biofilters Developed Draft Assessment Tool Finalized Assessment Tool & Industry Roll-Out Updates Updates Workshop No. 1: Review of Survey Results and Themes Workshop No. 2: "As Is," "Should Be," "Uncertainties" and "Tools" Workshop No. 3: Assessment Tool Draft Workshop No. 4: Assessment Tool Live Preview Beta- Testing

The Conversion Assessment Tool The Tool Does: Identify factors that can negatively affect biofilter performance Identify associated mitigation strategies Establishes facilityspecific relative suitability for conversion The Tool Does Not: Apply to groundwater Limit the application of biofiltration Replace a robust process evaluation (e.g., pilot study)

Download the Assessment Tool from the Project Website The Macro-Based Excel (.xlsx) can be Downloaded and Saved Locally Look under Web Tools http://www.waterrf.org/pages/projects.aspx?pid=4496

Step 1: Complete Survey Questions Utilities answer 24 multiple choice or select all that apply questions related to: Water Quality Design Criteria Performance Goals Operational Information Other Key Factors

Step 2: Data Calculator (Optional) Utilities may enter water quality data instead of selecting a range for the filter influent: TOC Temperature AOC The Assessment Tool will also calculate key statistics and compare them to data provided in the Biofiltration Knowledge Base.

Step 3: Conversion Assessment Report Utilities are provided a printer-friendly report summarizing, for each question answered: Category Question Selected answer Suitability for conversion to biofiltration Text description of suitability Mitigation strategies

Step 3: Conversion Assessment Report

Step 4: Conversion Assessment Report Utilities are provided a printer-friendly report comparing their planned facility to those facilities in the Biofiltration Knowledge Base Graphs summarize Knowledge Base Facilities Option Selected by the Utility Highlighted in Blue

Guidance Manual

Key Steps were Identified for Each Stage of the Conversion Process Planning Evaluation Implementation

Biofilter Conversion Planning Tasks Conversion Assessment Tool Assess potential benefits & challenges Determine water treatment & operational goals Determine suitability Assess existing facility & resources Identify potential monitoring parameters Identify aspects to be evaluated Determine potential process modifications Evaluation at Bench-, Pilot-, or Full-Scale Systems

Biofilter Conversion Evaluation Tasks Identify Water Sources Revisit Treatment Goals Determine Biological Acclimation Testing Design Assess Available Budget Determine Testing Parameters Determine Testing Schedule Refine Monitoring Parameters Conduct Testing Determine Removal Efficiency/Kinetics Assess Effectiveness of Monitoring Parameters Test Process Optimization Strategies Determine Process Upsets Select Key Parameters for Full-Scale Implementation Evaluate Effectiveness of Mitigation Strategies

Biofilter Conversion Implementation Tasks Relocate Chlorine Injection Implement Process Modifications Add Ozone Contactor (if desired) Implement Other Modifications Start Biofilter Operation Assess System Performance Optimize Operating Conditions Test the Modifications Implement Mitigation Strategies

WRF 4496: Converting to Biofiltration?

Other Project Team Members Jason Carter - Arcadis Chance Lauderdale - HDR Orren Schneider American Water John Dyksen Suez Scott Summers University of Colorado Foundation Research Managers Hsiao-wen Chen Kenan Ozekin Acknowledgements Project Advisory Committee Chris Owen Tampa Bay Water David Scott Toronto Water Eva Nieminski Utah Department of Environmental Quality Hua Jiang Tulsa Metropolitan Utility Authority Jen Smith CDM Smith Participating Utilities City of Peoria, AZ City of Phoenix, AZ Greenville Utilities Commission, NC Greater Cincinnati Water Works, OH Gwinnett County Department of Water Resources, GA Iowa American Water Jordan Valley Water Conservancy District, UT Kentucky American Water Lyonnaise-Des-Eaux, France Metropolitan Water District of Southern California, CA New Jersey American Water Newport News Waterworks, VA Suez, NJ Trinity River Authority, TX Tampa Bay Water, FL Toronto Water, Canada City of Tulsa, OK Utah Department of Environmental Quality, UT

Questions & Answers

Thank You Comments or questions, please contact: kozekin@waterrf.org GUpadhyaya@carollo.com Jbrown@Carollo.com Ashley.Evans@arcadis.com For more information visit: www.waterrf.org