6/24/2014 HIGHEST PRIORITIES: No More Taste & Odor Complaints Implementing Strategies to Address Algal Toxins for the City of Fairmont, MN PRESENTATION BY: Troy Nemmers, PE Director of Public Works/ City Engineer Jason Kosmatka, PE AE2S Project Manager CONFERENCE: 2014 Surface Water Treatment Workshop Fargo, ND Presentation Topics • Planning – How did we get to where we are now? • • • • T&O Pil t St d T&O Pilot Study Construction Start‐up Results 1 6/24/2014 FAIRMONT WTP Connections • 4,079 Residential • 500 Commercial • 16 Industrial Population • 10,500 residents Capacity • Built in 1926 • 1961 Expansion ‐ 4.5 MGD 1961 E i 4 5 MGD • New WTP ‐ 5.4 MGD Treatment • Class A Lime Softening with Filtration FACILITY PLANNING Source Water Evaluation Existing Water Source Budd Lake Sufficient Quantity Q y Adequate Quality Taste and Odor Mitigation g Alternative Water Source Groundwater Sufficient Quantity Hardness Removal Requirements (804 mg/l) TDS (1080 mg/l) Sulfate (573 mg/l) Sulfate (573 mg/l) Gross Alpha (25.1 pCi/l) Cost to Develop Budd Lake selected… 2 6/24/2014 FACILITY PLANNING Treatment Target Goals Budd Lake Surface Water Treatment – – – – – – – – – Algae Removal Softening Turbidity Control Pathogen Removal and/or Inactivation TOC Removal Disinfection Emerging Contaminants (ECDs, PCPs, PhACs) Multi‐Barrier Treatment Approach Taste and Odor Control FACILITY PLANNING Taste and Odor Control Blue‐green algae blooms = cyanobacteria Cyanobacteria cells die/burst and release… / Taste and odor constituents Cellular Constituents • Geosmin and 2‐methylisoborneol (MIB) • Aesthetic quality issue • Not regulated MIB geosmin microcystin other cyanotoxins Cyanotoxins • Mi Microcystin and cylindrospermopsin i d li d i • Health hazard studies link to illness, cancer • Currently unregulated • On EPA Contaminant Candidate List Extra-Cellular Extra Cellular Constituents MIB cell lysis geosmin released microcystin other cyanotoxin 3 6/24/2014 FACILITY PLANNING Taste and Odor Control Budd Lake blue‐green algae blooms g Geosmin • Earthy odor • Early spring MIB • • • • Musty odor 10 ng/l threshold Late summer to early fall Late summer to early fall Less prevalent than geosmin Cyanotoxin June T&O event on Budd Lake… Geosmin nanograms/liter (ng/l) Recommended Threshold 30 ng/l Lake Surface ~16,000 ng/l Intake Level (16-20 ft deep) ~70-80 ng/l Microcystin micrograms/liter (µg/l) P t ti l Regulated Potential R l t d Threshold Th h ld Level L l 0 1 – 1 µg/l 0.1 /l Lake Surface ~160 µg/l Intake Level (16-20 ft deep) ~0.5 µg/l • Most prevalent species – Microcystin Budd Lake New Conventional Softening & Filtration Softening & Filtration Water Treatment Plant… Onsite verification of T&O control technologies required prior to finalization of preferred WTP concept Algae Removal Dissolved Air Flotation?? Softening Conventional Softening and Recarbonation Filtration Conventional Filtration Taste & Odor Control ??? Residual Disinfection Chlorine Clearwell High Service Pumps 4 6/24/2014 TASTE AND ODOR PILOT STUDY Treatment Technologies Treatment Technology T&O Removal Efficiency Cyanotoxin Removal Efficiency Piloted? Dissolved Air Flotation (DAF) (cellular) Yes Membranes (extra‐cellular) No, membranes eliminated from consideration Ozone (extra‐cellular) Yes UV with Hydrogen Peroxide (UV/H2O2) (extra‐cellular) Yes Granular Activated Carbon (GAC) Adsorption (extra‐cellular) Yes APPLICATION OF STUDY RESULTS Best performing technology = GAC with KMnO4 MIB/geosmin removal Cyanotoxin (microcystin) removal Multi‐barrier treatment for cyanotoxin removal Supported by Odor Panel preference Results indicate presence of cell bound T&O Results indicate presence of cell‐bound T&O Future WTP should focus on removal of cells in‐tact where possible. Technologies include: • Dissolved Air Flotation (DAF), or • Co‐precipitate with lime solids 5 6/24/2014 FUTURE WTP Budd Lake Treatment Train Selection Softening & Algae Removal Chemical Feeds Flocculant l l Coagulant Lime Soda Ash Phosphate Filter aid Sodium Permanganate Chlorine Ammonia Filtration Conventional Softening and Recarbonation Conventional Filtration Cyanotoxin Oxidation NaMnO4 Taste & Odor Control GAC/BAC Residual Disinfection Chlorine Clearwell High Service Pumps SCIENCE BEHIND TREATMENT DESIGN STEP 1 STEP 2 Settle out as Settle out as much algae as possible Filter out algae Filter out algae carried over from SCB Polymer is our friend (when required)!!!! Found Polyacrylamide Found Polyacrylamide worked best w/ algae Algae is very difficult to filter (~5um) STEP 3 CHOP! Lyse any algae that went through filters Use an oxidant to b t ll ll burst cell wall Cyanotoxins are now more readily assimible as AOC for biological growth 6 6/24/2014 FAIRMONT WTP CONSTRUCTION PHASE Excavation 7 6/24/2014 CONSTRUCTION PHASE Subgrade Level CONSTRUCTION PHASE Subgrade Level 8 6/24/2014 CONSTRUCTION PHASE Gallery Level CONSTRUCTION PHASE Gallery Level 9 6/24/2014 CONSTRUCTION PHASE Operations Level CONSTRUCTION PHASE Operations Level 10 6/24/2014 CONSTRUCTION PHASE Intake Pipe Screen CONSTRUCTION PHASE Intake Pipe Screen 11 6/24/2014 CONSTRUCTION PHASE Intake Pipe Screen CONSTRUCTION PHASE Filters 12 6/24/2014 CONSTRUCTION PHASE Filters CONSTRUCTION PHASE Equipment 13 6/24/2014 CONSTRUCTION PHASE Equipment CONSTRUCTION PHASE Equipment 14 6/24/2014 MISCELLANEOUS STATISTICS • Started in August 2011, g Substantially complete in Sept. 2013 • Demo of old WTP ongoing • Final Completion July 2014 • 8,500 c.y. of cast‐in‐place concrete • 800 tons of rebar • Motion sensing lights • Solar tubes 15 6/24/2014 STARTUP Lessons Learned • No need for seeding • Be mindful of water quality in Reclaim Basin – Dead algae • Conversion of GAC to BAC is Synergistic • Avg. 20‐30 complaints per year with old WTP – One complaint so far STARTUP Algae Bloom – St Startup began in mid‐August t b i id A t 2013 – Severe Algae bloom in early September – Overwhelmed Clarifier – Jar Tested Polymers • AF 4355 EHW (polyacrylamide) – Alge counters available!! counters available!! Raw Water Ammonia Spike! – Large rain event – 0.2 mg NH3/l to 0.7 mg/l – Had to totally adjust disinfection strategy 16 6/24/2014 PERFORMANCE MEASURES Fairmont Surface Water Plant TOC Removal Results 90 80 % TOC removed before biological filters went online % TOC removed after biological filters went online % TOC removal required 70 % TOC Removed 60 50 40 30 20 10 0 Month‐Year PERFORMANCE MEASURES Trihalomethane (THM) Results Cedar Park Rd ‐ Cedar Park Hwy 15 & I90 ‐ Holiday Inn 2555 Lake Avenue ‐ Kenway Engineering Food & Fuel 1025 Bixby Rd ‐Tank Farm 1400 E. 8th St ‐ Cloverleaf Refrigeratio MCL 140 Conccentration µg/L 120 100 80 60 40 20 0 1/17/2012 4/25/2012 7/12/2012 10/30/2012 3/11/2013 6/10/2013 9/10/2013 12/10/2013 3/5/2014 Time 17 6/24/2014 PERFORMANCE MEASURES Haloacetic (HAA5) Results Cedar Park Rd ‐ Cedar Park Hwy 15 & I90 ‐ Holiday Inn 2555 Lake Avenue ‐ Kenway Engineering Food & Fuel Food & Fuel 1025 Bixby Rd ‐Tank 1025 Bixby Rd Tank Farm Farm 1400 E. 8th St ‐ Cloverleaf Refrigeratio 1400 E. 8th St Cloverleaf Refrigeratio MCL 70 60 Concentration µg/L 50 40 30 20 10 0 1/17/2012 4/25/2012 7/12/2012 10/30/2012 3/11/2013 6/10/2013 9/10/2013 12/10/2013 3/5/2014 Time THE FUTURE OF BIOFILTRATION Epiphany in Water Treatment Don’tt Kill It! Feed them, Don Kill It! Feed them, and they will grow!! If the food is there, the biology will grow May have to augment food: Phosphate, ethanol, DO Europe has decades of experience Treatment Candidates: Algal Toxins (MIB, Geosmin, Microcystin) Iron Manganese Treatment Candidates: Raw Water Ammonia ~ 2.0 mg/l with Aeration •Takes 4.57 mg O2 for each mg of NH4+ • Max DO is about 10.5 mg/l ~ 4.0 mg/l with continuous aeration • Ammonia contactor • Study done by Dr. Darren Lytle, EPA Bromate Perchlorate Ozone quenching VOCs Pesticides, MTBE Hexavalent Chromium 18 6/24/2014 THE FUTURE OF BIOFILTRATION Considerations: DO EBCT Food (100C : 10N : 1P) Biofilm (EPS) control Disinfection Strategy Ammonia Analyzer Algae Probes (ATP) Filters in Series Benefits: Chemical Savings $$ Biologically Neutral Water Green/Sustainable It’s Happening More than We Know! Regional Utility Raw Ammonia: 1.6 mg/l Feed 3.8 mg Cl2/l 2.4 : 1 ratio 2.4 : 1 ratio Free Chlorine: 1.35 mg/l Tot. Chlorine: 1.80 mg/l THANK YOU! Questions? Q ti ? Jason Kosmatka, Project Manager [email protected] 19
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