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Overview of the Microbial and Disinfection By Products Rules in Alaska

Overview of the Microbial and Disinfection By Products Rules in Alaska. Presented by: Jeanine Oakland Statewide Compliance/Enforcement Coordinator Drinking Water Program, ADEC. Presentation Objectives. Brief overview of the background of the Microbial and Disinfection By Product (DBP) Rules

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Overview of the Microbial and Disinfection By Products Rules in Alaska

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  1. Overview of the Microbial and Disinfection By Products Rules in Alaska Presented by: Jeanine Oakland Statewide Compliance/Enforcement Coordinator Drinking Water Program, ADEC

  2. Presentation Objectives • Brief overview of the background of the Microbial and Disinfection By Product (DBP) Rules • Review of the Public Water System (PWS) compliance with Stage 1 and Long Term 1 Rules in Alaska • Discuss common violations PWS are generating under these rules • Significant Non-Complier (SNC) status

  3. Background information • Disinfection of drinking water is one of the major public health advances in the 20th century. One hundred years ago, typhoid and cholera epidemics were common through American cities; disinfection was a major factor in reducing these epidemics. • What we know now……….. • Some microbial pathogens, such as Cryptosporidium, can cause illness and are resistant to traditional disinfection practices. • Disinfectants themselves can react with naturally-occurring materials in the water to form unintended byproducts which pose health risks.

  4. What does this mean for Drinking Water Professionals? We are charged with striking a balance between strengthening disinfection practices to provide protection against microbial pathogens while minimizing the creation of disinfection by products.

  5. Public Health Impacts for Enhanced Surface Water Treatment Rules The Science Advisory Board (SAB) cited drinking water contamination as one of the most important environmental risks and indicated that disease-causing microbiological contaminants (i.e., pathogens such as, bacteria, protozoa, and viruses) are probably the greatest remaining health risk management challenge for drinking water suppliers. EPA has determined that the presence of microbiological pathogens in public water supplies is a health concern. If finished water supplies contain microbiological contaminants, illnesses and disease outbreaks may result. • Disease symptoms may include diarrhea, cramps, nausea, jaundice, headaches, and fatigue. • Cryptosporidiosis in particular can manifest into a severe infection that can last several weeks and can cause death in individuals with compromised immune systems • 1993 Milwaukee, WI Cryptosporidium caused intestinal illness affecting 400,000 people. 4,000 were hospitalized and at least 50 deaths were attributed to this outbreak at a public water system.

  6. Public Health Impacts for Disinfection By Products • Epidemiology and toxicology studies have shown a link between bladder, rectal and colon cancers and DBP exposure. • Additionally, human epidemiology studies report an association between chlorinated drinking water and reproductive and developmental endpoints such as spontaneous abortion, stillbirth, neural tube defects, pre-term delivery, intrauterine growth retardation, and low birth weight.

  7. Alaska’s Public Water System Overview • Total of 1,597 Public Water Systems (CWS, NTNC, TNC) • 282 use Surface water Source (includes GWUDISW, and SW Purchased systems) • 1,315 use Ground water Source (includes GW Purchased) • 460 PWS are practicing some form of disinfection • Filtration Types: Majority of Alaska PWS fall into the “Alternative” filtration category under Enhanced Surface Water Treatment Rules, remaining are listed; • 36 Direct Filtration 2 Slow sand 7 Unfiltered • 15 Conventional 1 Diatomaceous Earth DEFINITIONS CWS- Community Water System (Class A) NTNC- Non-Transient Non-Community Water System (Class A) TNC- Transient Non-Community Water System (Class B) GWUDISW- Ground Water Under the Direct Influence of Surface water Purchased Systems- Public Water Systems that purchases water from another water system

  8. Enhanced Surface Water Treatment Rules: The Basics • Interim Enhanced SWTR-Applies to SW and Ground water under direct influence of surface water (GWUDI) serving greater than 10,000 people • Long Term 1 ESWTR-Applies to SW and GWUDI systems serving less than 10,000 people • Requiressystems to achieve a 2-log removal (99 percent) of Cryptosporidium. • Filtered systems must comply with strengthened combined filter effluent (CFE) turbidity performance requirements (specific requirements based on type of filtration used by system) • Conventional/Direct filtration systems subject to continuous individual filter monitoring requirements (based on # of filters) – follow up actions may be required • Long Term 2 ESWTR -Applies to all SW and GWUDI systems • Requires systems to monitor source water in order to calculate average Cryptosporidium concentration to determine whether additional treatment is required. (Filtered systems under 10,000 monitor source water for E. Coli in lieu of Cryptosporidium monitoring)

  9. All LT1 violations by violation category Treatment Technique 19% Monitoring/Reporting 81%

  10. What were the Monitoring/Reporting (M/R) violations issued for? • Failure to collect and report all the required combined filter effluent turbidity samples; and/or • Failure to report that all individual filter monitoring had been conducted • What were the Treatment Technique (TT) violations issued for? • Combined filter effluent exceeds 1 NTU/state-set maximum requirements; and/or • More than 5% of the monthly combined filter effluent samples exceed 0.3 NTU/state-set maximum standards This violation applies to conventional/direct filtration systems only

  11. Northern Western Southeast These 3 areas represent the largest number of systems in violation of LT1, but they also have the largest number of conventional and direct filtration systems

  12. Disinfection By Product Rules: The Basics • Stage 1- All CWS/NTNC systems that add a disinfectant (and TNC that use chlorine dioxide) • Required to monitor for DBPs (TTHM/HAA5s, and Bromate for ozone systems), compliance calculated on running annual average. • Required to collect distribution chlorine sample at same time and place as Total Coliform sample(s), compliance calculated on running annual average. • For SW systems using Conventional filtration have additional requirements for removing DBP precursors, quarterly compliance calculated on running annual average. • Stage 2-All CWS/NTNC systems that add a disinfectant other than UV • Requires some systems to complete an Initial Distribution System Evaluation (IDSE) to characterize DBP levels and identify monitoring locations in distribution system • IDSE Options: Standard Monitoring, System Specific Study, 40/30 Certification, and/or Very Small System Waiver • Required to monitor for DBPs (TTHM/HAA5s), compliance calculated on Locational running annual average

  13. Percentage of all Stage 1 violations issued by Region Northern Area 32% Western AK 32% Mat-Su Valley 5% Anchorage 2% Kodiak, Aleutians, Dillingham 13% Southeast 10% Kenai Peninsula 6%

  14. Stage 1 violations issued by violation type Maximum Contaminant Level (MCL) or Maximum Residual Disinfectant Level (MRDL) Treatment Technique (TT) 1% 7% 60% of ALL Stage 1 violations are for failure to monitor/report distribution chlorine at the same time and place as routine total coliform bacteria sample. Monitoring/Reporting 92%

  15. What were the Monitoring/Reporting (M/R) violations issued for? • Failure to collect and report distribution chlorine samples; • Failure to collect and report TTHM/HAA5 samples; • What were the Maximum Contaminant Level (MCL) and/or Maximum Residual Disinfectant Level (MRDL) violations issued for? • Exceeding TTHM/HAA5 MCL NOTE: No MRDL violations have been issued. • What were the Treatment Technique (TT) violations issued for? • Failure to meet DBP precursor removal (TOC) This requirement only applies to conventional filtration systems

  16. Significant Non-Complier (SNC) (pronounced “snick”) EPA set the SNC criteria for each Safe Drinking Water Act (SDWA) rule based on violation type (severity) and frequency of the violations. EPA also set criteria for how a system can Return to Compliance (RTC) their SNC status (i.e. get off the SNC List) The acronym “SNC” refers to the status of serious, frequent, or persistent non-compliance of the Drinking Water regulations by a PWS.

  17. Surface Water and Stage 1 SNC • SNC Criteria: • Various combinations of violations (M/R, MRDL, MCL, and/or TT) in a 12 month period • Based on routine monitoring requirements • Includes either major or minor violations Surface Water SNC(Includes Surface Water Treatment Rule, Enhanced Surface Water Treatment Rule, and Long-Term 1 Enhanced Surface Water Treatment Rule) How to RTC Submit 6 (SIX!) consecutive months with ZERO SWTR violations • How to RTC • Submit 12 (TWELVE!) consecutive months of ZERO DBPR violations Stage 1 SNC

  18. DW Program Tracks Compliance Trends Stage 1 SNCs No SNC list from EPA

  19. CCR VOC TCR Surface Water Stage 1 Nitrate Failure to consistently monitor distribution chlorine at same time and location as routine Total Coliform (bacti) sample. (OVER 70% of Stage 1 SNCs)

  20. In Summary……. • Important to strike that balance between strengthening disinfection practices to provide protection against microbial pathogens while minimizing the creation of disinfection by products. • Overall PWS struggle with the monitoring and reporting for LT1 and Stage 1. Without monitoring we cannot know the quality of water being served to customers. • NOTE: In particular for Stage 1- Take your distribution chlorine samples consistently at the same time and location of your routine total coliform bacteria sample!

  21. References EPA Websites LT1 Information http://www.epa.gov/safewater/mdbp/lt1eswtr.html LT2 Information http://www.epa.gov/safewater/disinfection/lt2/index.html Stage 1 Information(will have to search this page a little more than the others for Stage 1 specific information) http://www.epa.gov/safewater/mdbp/implement.html Stage 2 Information http://www.epa.gov/safewater/disinfection/stage2/index.html DW Program Website Link to Operator Report Forms (by filtration type) http://www.dec.state.ak.us/eh/dw/publications/forms.html Link to “How to take a Distribution Chlorine Sample” handout http://www.dec.state.ak.us/eh/docs/dw/Chlorine%20Residual%20Sample%20Document.pdf

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