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Long Term 2 (LT2) Enhanced Surface Water Treatment Rule

Long Term 2 (LT2) Enhanced Surface Water Treatment Rule

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Long Term 2 (LT2) Enhanced Surface Water Treatment Rule

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  1. Long Term 2 (LT2) Enhanced Surface Water Treatment Rule TCEQ Environmental Trade Fair May 2015

  2. Surface Water • Serves majority of people in U.S. • Source for most large systems in Texas • Especially vulnerable to microbial contamination • Cryptosporidium, E. coli, and Giardialamblia present in most surface water • Series of regulations addresses heightened risk

  3. SWTR (1989) • All Subpart H systems • Reduce risks from Giardia lamblia & viruses IESWTR (1998) • Subpart H systems serving > 10,000 • Address Crypto with improved treatment LT1ESWTR (2002) • Requirements similar to IESWTR applied to Subpart H systems serving < 10,000 LT2ESWTR (2006) • All Subpart H systems • Target additional treatment at highest-risk systems Surface Water Treatment Rules Summary

  4. Subpart H Sources • Surface Water – rivers, lakes, reservoirs, canals, etc. • Ground Water Under the Direct Influence of Surface Water (GUI) • Rainwater Collection Systems

  5. What is Cryptosporidium? • Protozoan parasite that lives and reproduces in one host • Transmission • Contaminated food or water • Direct contact with feces • Direct or indirect contact with sick individuals • Oocysts are very small: 4-5 microns • Can survive for months without a host

  6. Cryptosporidium (Crypto) • Resistant to traditional disinfectants such as free chlorine • Can pass through some filters due to small size • Typical filtration treatment techniques and alternative disinfectants (Chlorine Dioxide, Ozone, UV) can remove and/or inactivate Crypto

  7. Health Effects of Cryptosporidium • Causes cryptosporidiosis • Mild to sever diarrhea, dehydration, stomach cramps, and slight fever • Immunocompromised individuals can die from infection • No known cure for cryptosporidiosis

  8. Outbreaks Cryptosporidiosis Outbreaks in U.S. Municipal Water Supplies

  9. Purpose of the LT2ESWTR • Improve public health protection for surface water, GUI, and rainwater systems • Reduce illness caused by Crypto and other microorganisms • Tailor requirements based on: • Level of treatment • Source water quality • Water system size • Provide system with flexibility

  10. LT2ESWTR Overview • Source water monitoring • Screening procedure for small systems • Target treatment for highest-risk systems • Additional treatment expected to be the exception instead of the rule

  11. 1 0 2 3 4 5 LT2ESWTR Process Systems Subject to LT2 Small systems w/ low E. coli Initial Round Source Water Monitoring Systems installing max treatment Bin 1 systems Bin Classification Choose Toolbox Option(s) Implement Tool(s) Second Round Source Water Monitoring

  12. Round 2 Start-up Package for Monitoring Plans Sent out to systems prior to sampling start dates and includes: • Sampling requirements • Sampling location worksheet • Sampling location schematics • Sampling schedules for Crypto and E. coli

  13. Single Source Sample Location Water Treatment plant LT2 Sample point Raw water intake Source water Backwash water recycle(if applicable) Raw water chemical building LT2 Sample point Chemicaladdition Backwash water recycle(if applicable)

  14. Multiple Sources Sample Location Raw water blending station Chemical addition Source water “A” LT2 Sample point Raw water intake Water Treatment plant Source water “B” Backwash water recycle(if applicable)

  15. Round 2 Schedules

  16. Combined Distribution Systems • The Combined Distribution System (CDS) requirements only apply to systems (wholesalers) that provide (not necessarily sell) water to at least one other PWS • Monitoring requirements are based on the population of the largest water system in a CDS

  17. Source Water Monitoring Round 2: Schedules 1-3 24 samples plus two matrix spikes required for: • Cryptosporidium • Select an EPA certified lab to conduct Cryptoanalysis • E. coli • Select a NELAP certified lab to conduct analysis with the approved enumeration method • Turbidity • Conduct turbidity analysis at your own treatment plant

  18. Source Water Monitoring Round 2: Schedules 1-3 • Matrix spike samples for the 1st and 13thsample • Collect samples within a two-day window on either side of the dates specified in LT2 monitoring plan • Send individual sampling results to the LT2 Program by email at, by facsimile at 512-239-6050, or by correspondence at: LT2 Program TCEQ Public Drinking Water Section – MC 155 PO Box 13087 Austin, TX 78711-3087

  19. Source Water Monitoring Round 2: Schedule 4 • Option to monitor for e. coli instead of Cryptosporidium • Collect one sample every 2 weeks for 12 months (26 samples total) • Cryptosporidium monitoring is triggered if a 12 month running average exceeds 100 colony forming units (CFU) per 100 mL

  20. Source Water Monitoring Round 2: Schedule 4 • Cryptosporidium Monitoring Options • Once per month for 24 months • Twice per month for 12 months • Samples still must be equally spaced over the 12 or 24 month period

  21. Treatment Options • Water systems can opt out of source water monitoring • Provide 5.5-log removal/inactivation of Crypto at ALL times • Need to prove the 5.5-log removal/inactivation by a Demonstration of Performance • Also, is source water monitoring is indicating a Bin 4 level of treatment, system can stop monitoring and agree to provide full treatment

  22. Treatment Options • Consider before choosing treatment: • Currently most systems in Texas are classified as Bin 1 in Texas • There are 9 PWSs (10 plants) classified as Bin 2 systems and required to provide additional treatment at their plants • Full treatment option may be a viable option if you already provide “Bin 1” filtration and use either ozone or UV (see rule CT tables)

  23. Calculating Bin Concentration • At the end of testing, TCEQ staff determine the system’s “Bin” level. This will determine the amount of treatment required by the system. • Crypto testing: For 24 to 27 samples, TCEQ calculates the average concentration for every rolling 12 month period and selects the highest average. • E. coli testing: Calculate the average concentration for all samples.

  24. Bin Classification • Water systems serving less than 10,000 people which only monitored for E. coli are automatically placed into Bin 1 • Does not include small systems which triggered Crypto sampling by having an E. coli average greater than 100 MPN/100mL

  25. Levels of Additional Treatment

  26. CryptoRemoval Credits • Treatment plants using coagulation, flocculation, and granular media filtration receive 2,5-log Crypto removal credit. • Treatment plants using coagulation, flocculation, clarification, and granular media filtration receive 3.0-log Crypto removal credit. • TCEQ assigns Crypto removal credit to treatment plants using bag, cartridge, or membrane filters on an individual basis.

  27. Microbial Toolbox Options • Watershed control program • Alternative source • Pre-sedimentation basin with coagulation • Two-stage lime softening • Bank filtration • Combined Filter (CFE) Performance • Individual Filter (IFE) Performance • Demonstration of Performance

  28. Microbial Toolbox Options • Bag or Cartridge Filters (individual filters) • Bag or Cartridge Filters (in series) • Membrane Filtration • Second stage Filtration • Slow sand Filters • Chlorine dioxide • Ozone • Ultraviolet (UV)

  29. Treatment Compliance Deadlines

  30. Treatment Compliance Deadlines • States may allow up to an additional two years for complying with treatment requirements for systems making capital improvements

  31. QUESTIONS? Tamira Konkin-Garcia (512) 239-1298 Sean Ables, P.G. (512) 239-1758