Assess then Address: Evaluating Contaminant Sources and Selecting Viable Treatment Barriers for the Clapper Road WTP

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1 Assess then Address: Evaluating Contaminant Sources and Selecting Viable Treatment Barriers for the Clapper Road WTP April 14, 2016 Marc Santos, PE Hazen and Sawyer

2 Agenda Background Objectives/Strategy Plant Analysis and Sampling Bench-scale Testing Final Selected Treatment Train Summary and Strategy Checklist 2

3 Clapper Road Water Treatment Plant - Overview Town of Bethlehem 6 MGD Design Flow Groundwater Hudson River Infiltration Gallery and Well Field 20 MG Storage Reservoir Back-up supply Conventional Treatment Trident Clarification 3

4 Clapper Road WTP Process Flow Diagram and Well Field 4

5 Average Water Quality ph 7.0 Alkalinity 153 mg/l as CaCO 3 TOC Iron Manganese Ammonia 2.7 mg/l 3 mg/l 0.6 mg/l 0.5 mg/l 5

6 Key Operational Concerns - Objectives Iron and Manganese Taste and Color Maintain Cl 2 residual through reservoir Moderately High Ammonia high chlorine demand Disinfection Byproducts Treated Water DBPs close to MCLs 6

Project Strategy 1 Understand the contaminant sources

system 2 Optimize existing barriers in WTP and consider

coming into WTP and 3 Identify additional barriers and

7 Project Strategy 1 Understand the contaminant sources and characterize throughout treatment and distribution system 2 Optimize existing barriers in WTP and consider operational changes that will reduce contaminants coming into WTP and 3 Identify additional barriers and select new treatment technologies to deal with contaminants 7

8 Clapper Road WTP Approach Review Process and Historical WQ Plant-wide Sampling Bench-scale Testing: Enhance Coagulation/Removal Fe and Mn Oxidation PAC removal Treatment Train Selection Piloting of Selected Train 8

9 Understand Process and Water Quality Understand process flow diagram Review operating flows and chemical usage Review historical water quality (targets and related parameters) Perform additional WQ testing as needed Identify existing barriers (oxide coated media, clarification, etc.) 9

10 Understand - Plant-wide Sampling Proper sampling techniques and holding time Sufficient sampling points to understand the process Split sampling analysis Record operating data at time of sampling 10

CRWTP Plant-wide Sampling Source to Finished Water Sampling points before and after each process step DBPs Total/dissolved organic carbon THMs

11 CRWTP Plant-wide Sampling Source to Finished Water Sampling points before and after each process step DBPs Total/dissolved organic carbon THMs and HAAs Iron and Manganese Fractionation total, dissolved, colloidal Analysis of Trident buoyant adsorption media Filter core of filter media 11

12 THMs (ug/l) CRWTP Split Sampling - DBPs Eurofins TOB Site 2 Site 3 Site 4 Site 6 Site 7 Site 8 12

13 Fe and Mn Fractionation Total = Particulate + Colloidal + Dissolved Membrane filter: 0.2 or 0.45 µm Particulate Ultrafilter of 30 K Colloidal = Smaller than 0.45 (or 0.2) µm Dissolved Importance of knowing form: Sometimes measured Mn in treated water and concluded that oxidation was ineffective Mn may be present as colloidal Mn (oxidized), but is passing though the filter as very small particles. 13

14 Methods for Determining Metals Fractionation HACH Colorimeter Filters um (colloidal/dissolved) Ultrafiltration 30k (dissolved) 14

15 CRWTP Plant Wide Sampling Manganese Through Plant 15

16 Trident Buoyant Adsorption Media Visible Fe/Mn coating on media Can be cleaned with acid Possible benefit for Mn reduction 16

17 Anthracite/Sand Filter Cores From Opflow August

18 On-site Oxidation Testing Manganese Oxidation 18

19 Optimize and Identify - Bench-scale Testing Manganese Removal - Chemical Oxidation DBP Reduction - Enhanced Coagulation and Clarification 19

20 Chemical Oxidation Fe and Mn Control Considerations Stoichiometry Need to add sufficient oxidant for the oxidation-reduction (redox) reaction TOC (NOM) - affects stoichiometry and kinetics Must also satisfy competing demand for the oxidant from other reduced species (NOM, and any other reduced compounds) Rate of Reaction reaction kinetics Need sufficient time for oxidation Rate affected by ph, NOM, temperature 20

21 Mn Oxidation Testing Chemical Oxidants Chlorine Dioxide Sodium Permanganate Ferrate Doses around stoichiometric ratios Detention times similar to full-scale Chemical Oxidant Chlorine Dioxide Sodium Permanganate Ferrate Stoichiometry Amount 2.46 mg ClO 2 /mg Mn 1.72 mg NaMnO 4 / mg Mn 1.45 mg FeO 2-4 / mg Mn 21

22 Oxidant Demand Testing Results 22

23 Optimize Coagulation : TOC and Oxidized Fe/Mn Removal Conventional Settling DAF 23

24 % UV Removal Optimized Coagulation 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% cm cm cm cm cm cm -1 0% PC 2382 Dose (mg/l) 24

25 Excitation-emission Matrix (EEM) spectroscopy Raw Water Site 1 Enhanced Coagulation with PACl 25

26 Proposed Treatment Train 26

27 Strategy Checklist 1. Understand Sources of target contaminants and pre-cursors Form of metals (fractionation) and carbon (EEM) Current barriers in the process 2. Optimize Alternative source water practices Optimize Coagulation DBPs 3. Identify Oxidize metals remove via clarification Consider other WQ goals when selecting treatment Match treatment to constituent, multistep removal may be needed 27

28 Acknowledgements Dr. John Tobiason and Umass Amherst team Dr. Rob Sharp and Manhattan College team Richard Sayward and Staff Town of Bethlehem Julie Herzner Hazen and Sawyer Dr. Bill Becker Hazen and Sawyer 28

29 Questions / Discussion Marc Santos, PE msantos@hazenandsawyer.com

30 Piloting - DAF 30

31 DAF Jar Tester 31

Delvin DeBoer, Ph.D., PE. MN/ND/SD SWTW April 29, 2014 OUTLINE

Delvin DeBoer, Ph.D., PE. MN/ND/SD SWTW April 29, 2014 OUTLINE Physical/Chemical Process FUNDAMENTALS Delvin DeBoer, Ph.D., PE MN/ND/SD SWTW April 29, 2014 OUTLINE Properties of turbidity and organic matter Mechanisms of coagulation, coagulant chemicals and jar testing