1. Chlorine Disinfection of Drinking Water California Unified Program 8 th Annual Training Conference February 8, 2006 Presented by: Paul G. Beswick Metropolitan Water District of Southern California Environmental Support Services (213) 217-5533pbeswick@mwdh2o.com

2. TO DISTRIBUTION SYSTEM Typical Water Treatment Plant PRE- CHLORINATION Cl 2 Kills disease causing organisms and helps control taste-and-odor causing substances. DAF 9-20-00 FILTRATION Filters out remaining suspended particles CLEARWELL Provides contact time for disinfection. Stores water for high demand. Cl 2 NH 3 CHLORAMINES Kills disease causing organisms. Provides disinfectant residual for the distribution system. SEDIMENTATION Settles out larger suspended particles. COAGULATION / FLOCCULATION Gathers together fine light particles to form larger particles (floc) to aid the sedimentation and filtration processes. FLASH MIX Mixes chemicals with raw water containing fine particles that will not readily settle or filter out of the water. Cl 2 NaOH CORROSION CONTROL Adjusts the pH of the treated water to inhibit corrosion of pipelines.

3. The Chlorine Disinfection Process Public Health benefits of chlorination Public Health benefits of chlorination Process flow Process flow Process components Process components

4. Chlorination Public Health Benefit A critical role protecting US drinking water supply from waterborne infectious diseases for over 90 years A critical role protecting US drinking water supply from waterborne infectious diseases for over 90 years Cholera, typhoid, dysentery, hepatitis A virtually eliminated Cholera, typhoid, dysentery, hepatitis A virtually eliminated In over 98% of disinfection systems In over 98% of disinfection systems Germicidal potency, residual disinfection properties, efficiency, economy Germicidal potency, residual disinfection properties, efficiency, economy

5. Chlorination Public Health Benefit

6. All Uses of Chlorine

7. The Chlorination Process

8. Chlorine Rail Car Unloading 90 Ton rail cars

9. Chlorine Trailer Unloading 17/19 Ton Trailers

10. Stationary Chlorine Tank 25 ton stationary tank

11. Chlorine Cylinder Storage 1 ton cylinders

12. Chlorine Evaporators

13. Chlorinators

14. Ejectors

15. Treatment Chemical Storage ChemicalQtyCapacity Chlorine3 90 ton rail cars Caustic (25%) 8 127,000/ 50,000 gal. Aqueous Ammonia (19%) 4 13,000/10,000 gal.

16. Chlorine System Safety - What we are doing 24 hour monitoring and access control 24 hour monitoring and access control Detailed operating procedures Detailed operating procedures Highly trained staff Highly trained staff Leak sensors and alarms Leak sensors and alarms Automatic supply shut-off valves Automatic supply shut-off valves Chlorine containment and neutralization Chlorine containment and neutralization On-site emergency response capability + strong relationship with fire dept responders On-site emergency response capability + strong relationship with fire dept responders

17. Operator on duty 24 hours a day. Chlorine alarms are received in the Control Room. Chlorine facilities are visually inspected twice a shift. Control Room

19. Chlorine Trailer Manway Remote emergency shut-off capability Highly sensitive chlorine gas detector

20. Multiple Emergency Shut-off Locations Controlled from several strategic locations Shut-off is immediate

21. Monel Flex Hose Connection Durable/flexible connection Inspected/replaced regularly

22. Chlorine Gas Monitoring Continuous monitoring, alarms locally and in Control Room Sensors strategically placed throughout plant Calibrated regularly

23. Chlorine leak alarms Audio/Visual chlorine gas leak alarms - immediate notification to all plant personnel.

24. Vacuum Operation Chlorine piped to points of use throughout plant under vacuum Safest method of transmission

25. New chlorine containment facilities

26. Chlorine Cargo Trailers Inside Containment Chlorine Storage Bay

27. Caustic Neutralization System Two 3.5-Ton Chlorine Scrubbers

28. Chlorine Rail Car Containment

30. Chlorine Rail Car Scrubbers

31. Good Relations With Fire Dept. Responders

32. LAFD Visits Jensen Plant

34. Where Is The Real Chlorine Release Threat?!

35. Rural Bexar County, Texas June 28, 2004 3 dead, 50 hospitalized

36. Graniteville, South Carolina January 6, 2005 9 killed, 554 hospitalized, ~5,400 evacuated

40. Where Is The Real Chlorine Release Threat?! Two train wrecks in 6 months Two train wrecks in 6 months –resulted in significant chlorine releases –12 dead –over 600 taken to hospital –over 5,000 evacuated.

41. Chlorine Rail Transportation Issues Rail freight cost cutting, lack of re- investment, explosive growth, stretched resources Rail freight cost cutting, lack of re- investment, explosive growth, stretched resources Security Security –In transit –Storage while in transit Identifying hazmat derailment Identifying hazmat derailment Warning local first responders Warning local first responders Mobilizing specialist response team Mobilizing specialist response team