This document discusses odor control in wastewater force mains through superoxygenation. It describes two approaches to odor control - using chemicals or scrubbers to treat odors after formation, or preventing odor formation through superoxygenation. The document then provides details on a specific force main odor control project in Laguna Beach, CA where superoxygenation was used, reducing hydrogen sulfide levels from an average of 145 ppm to under 0.4 ppm.

1. FORCE MAIN ODOR CONTROL LAGUNA BEACH, CA WEF Odors and Air Emissions 2008

2. Allow it to form then treat it Chemicals or Scrubbers Prevent its formation SuperOxygenation TWO APPROACHES IN ODOR CONTROL

3. CORROSION CONCERN

4. Pure Oxygen Sustaining aerobic conditions Preventative form of Odor control Preventative form of Corrosion control Environmentally Friendly SUPER OXYGENATION D.O. levels of 50 – 100 mg/L D.O. Saturation = 40 mg/L at 1 ATM of Pressure using O2

5. TECHNOLOGY OVERVIEW Oxygen Gas Unscreened Raw Wastewater Force Main Oxygenated Raw Water Sidestream Pump

6. ECO 2 ® Oxygenation Cone System Intake System Discharge Oxygen Supply Booster Pump Influent 18” Force main 3 miles long Lift Station Wet Well TYPICAL FORCE MAIN INSTALLATION

7. SYSTEM COMPONENTS

8. Liquid Oxygen SOURCES OF OXYGEN O 2 Generator

9. ONSITE OXYGEN GENERATION

10. COST – LOX vs. GENERATION 5 Year N/A Payback $14,000 $24,500 Annual Operating Cost Electrical Cost $11,000 O&M Cost $3,000 Product Cost $18,500 Annual Lease $6,000 Operating Cost $53,000 $5,000 Capital Cost 1,000 1,000 Oxygen (lbs / day) GENERATION LOX

11. LAGUNA BEACH, CA Coastal Community Env. Conscious 3 Million Visitors / Year 28 Lift Stations 24,000 Users

12. BLUEBIRD FORCE MAIN Bluebird PS Transition Manhole 16,896 LF 24” Dia 1,500 gpm 6 Hr HRT

13. BLUEBIRD PUMP STATION

14. FORCE MAIN DISCHARGE

15. MONTAGE RESORT

16. UNTREATED H2S LEVELS Peak: 800 ppm Average: 145 ppm

17. Guaranteed Performance Level Average H2S < 5 ppm Return on Investment ROI < 4 years Increase Service Life of NCI Invisible Installation PROJECT OBJECTIVES

18. Rules of Thumb Design Data Checklist Design Calculations Performance Standard Economics SYSTEM DESIGN

19. DESIGN RULES OF THUMB 1. Oxygen Demand: 1 Hour HRT = 10 mg/L D.O. Uptake 2. Pressure Check: 1 ft Head Pressure = 1 mg/L D.O.

20. DESIGN DATA CHECKLIST

21. Force Main Specifications 16,896 ft 24” diameter Longest HRT - 6 hr 1,500 gpm ECO 2 System Design O2 Demand = 6 hr * 10 mg/L/hr = 60 mg/L 60 mg/L * 8.34 * 2.1 MGD = 1,000 lbs / day Pressure check = 70 ft = 70 mg/L (> 70 mg/L) (Rule of thumb = 1 ft of head = 1 mg/L) DESIGN CALCULATIONS

22. PERFORMANCE STANDARD Measurement Point at Force Main Discharge Manhole Gas Phase H 2 S Average < 5 ppm H 2 S

23. INSTALLATION INSIDE STATION

24. INSTALLATION LAYOUT Oxygen Generator Force Main Pump Force Main ECO2 Cone Main Level Basement Sidestream Pump

25. SYSTEM COMPONENTS

26. LAGUNA BEACH - H 2 S RESULTS

27. Average: 0.4 ppm LAGUNA BEACH - H 2 S RESULTS

28. BEFORE Average: 145 ppm

29. AFTER Average: 0.4 ppm

30. ECONOMICS - $40,700 Electrical Cost (Oxygen Generator) (15 hp Side stream Pump) - 3.6 Years Payback - $397,000 Capital Cost (Equipment + Installation) - $109,300 Annual Savings $150,000 - Chemical Cost CHEMICAL ECO2

31. Force Main Odor Control Primary Clarifier Odor Control Head Works Odor Control D.O. Discharge / TMDL Standards Lake and River Supplementation APPLICATIONS

32. TRA - Dallas, TX 150 MGD . 14,000 lb O 2 / day Anticipated Results: 0.0 mg/L DS into Primary Clarifier

33. Cheeney Creek WWTP - Fishers, IN 5.0 MGD . 5 hrs HRT Results: 5 - 10 mg/L D.O. at Plant Headworks Allisonville Road Smock Creek Hague Road

34. KSD - Kennebunk, ME 5.0 MGD . 210 lb O 2 / day Results: WWTP Plant D.O. Discharge 8 mg/L

35. GPA - Savannah Harbor, GA 22 MGD . 30,000 lb O2 / day Results: Cone D.O. Discharge 150 mg/L

36. David Shissler, City of Laguna Beach Graham Wright, City of Laguna Beach ACKNOWLEDGMENTS

38. BOD in water under anaerobic conditions causes microbial reduction of: SO 4 2- + BOD + No D.O. --------- H 2 S Sulfate-reducing bacteria cannot grow in the presence of D.O. H 2 S in the presence of O 2 H 2 S + O 2 + bacteria ---------------- H 2 SO 4 ROOT CAUSE OF ODOR / CORROSION

39. How do we influence the Rate of Oxygen Transfer?  DO = K 2 . A / V .(C sat -C act ).  t Increasing the area of Gas/Water contact, A / V Increasing the time of Gas/Water Contact,  t Increasing the D.O. saturation of water, C sat HENRY’S LAW AND GAS TRANSFER

40. FORCE MAIN ODOR CONTROL