Resolving Drinking Water Non-compliance MCL Violations

1. Resolving Drinking Water Non-complianceMCL Violations

2. KY Public Water System Violation Trends 2012: Chlorine, TOC, Coliforms, CCR, MOR

3. KY Public Water System Violation Trends

5. Total Coliforms/E. coli

6. Total Coliform • Positive total coliform/E.coli is almost always associated with problems with • Sample site • Sampling technique

7. Total Coliform—Sample Site • Sample Site (or “Hey I had a good chlorine residual at that site!!) • No outdoor faucets!! • The #1 reason for positives • No swing faucets • No dirty faucets • No hydrants • No need to disinfect and most definitely don’t “flame” a faucet • Good site and sample locations will reduce and even eliminate positive samples

8. Total Coliform—Sampling • All samplers shall be trained in the proper sampling technique • No old bottles or bottles that have been rolling around in the bed or floorboard of a vehicle • No setting tops down or in pockets or held in the mouth • If removing strainers, do so carefully • Keep samples at 4 degrees C in a dedicated cooler

9. RTCR Assessment Impact In wine there is wisdom, in beer there is strength, in water there is bacteria (David Auerbach 2002)

10. Disinfection By-Products

11. DBPs—At the Source • Start at the source • Pay attention to the source water total organic carbon (TOC) loading • Actual TOC data or UV254 • Is it related to algal blooms or rainfall or agricultural activity? • Treat the source if needed • Be careful using copper sulfate for algal control as it will break up the algae, causing T&O, turbidity and possibly release microtoxins

12. DBPs and Plant Design • It starts with good engineering • Design for the source water needs, not the “technology of the day” • Or the technology should resolve the problem • There should be flexibility in chemical feed points and what chemicals can be applied • This is a case of more is better • Too much design flow capacity (i.e., plant not operating) can create problems in the plant • No flow through means more time for the chlorine to react in sedimentation basins and clearwells

13. DBPs and Coagulation • Then move to the treatment process, starting with coagulation • Optimize coagulation • You may find that the coagulation dosage needed for organics removal is different than that for turbidity removal—this is called “simultaneous compliance” • Try feeding PAC • Although the dosages may be very high • Avoid the pre-chlorine feed site • Look at Step 2 jars or permanent alternative TOC compliance • Particularly if your system has TOC violations but not ones for DBPs

14. DBPs and Disinfection • Once done with the coagulation process, examine plant disinfection practices • Minimize the amount of pre-chlorine added • If chlorine usage is for oxidation as well as disinfection, evaluate other oxidants (KMnO4, H2O2) • Move the point of pre-chlorine addition to top-of-filter • PWSs must request to move the point of chlorination • Watch the chlorine levels leaving the plant • More is not always better

15. DBPs and Disinfection • For disinfection, what if the plant needs to move the point of chlorination but can’t because of the “1 log” C-T inactivation requirement?? • 2013 is a different drinking water world than 1998 • On a case-by-case basis, the DOW may reconsider the 1-log C-T inactivation but cannot lower it below 0.5-log • Back to “simultaneous compliance” • Decreasing DBPs while avoiding TCR problems

16. DBPs and Distribution Systems • And finally the distribution system • DOW data shows that the majority of the PWSs are forming the DBPs in the distribution system • Plant tap levels are low • Good communication between plant, distribution and management personnel is critical • No more “finger-pointing”

17. DBPs and Distribution Systems • Again, it involves good engineering • As the operator(s)—BE INVOLVED! • The engineered project should not compound or create DBP problems • More tanks, booster stations, long lines with minimal usage—not good • More water movement, more tank mixing--good • Does your system have a hydraulic model and does it consider water quality impacts? • In other words, water age

18. DBPs versus Booster Chlorination • This is a real dilemma • Low chlorine in an area with maybe the occasional positive TCR sample (maybe you ought to figure out why…) • Flushing doesn’t seem to help and is expensive • Booster chlorination is considered • Carefully examine where the booster station is placed (back to engineering and hydraulics) • If with a tank, after the tank is preferred • Automatic, SCADA control is preferred with an on-line chlorine analyzer • Seasonal booster chlorination is always when DBP formation is the highest

19. DBPs versus Water Age • Water Age • The older the water, the more likely DBPs will be formed Chlorine + organics + time = DBPs

20. DBPs versus Storage Tanks • Storage tanks • How many tanks are really needed? (and do regulations need to be reviewed to reflect the 2013 world?) • Too many tanks are being used for pressure and so the water in them cannot be adequately turned over • Is there a better way to avoid the tank-to-tank-to-tank movement of water? • Can you do more than monitor the water levels in the tanks—can you control it??

21. Multiple tanks in an area Multiple tanks & booster stations— Driven by terrain

22. DBPs versus Water Mains • Water Mains • In an effort to provide water to all KY residents by 2020, KY drinking water infrastructure is now available to 93-95% of Kentuckians • Residential water usage is dropping • Now estimated at 65 gallons per person per day • Number of people in a residence is dropping • In 1990s it was 3.3, in 2006 it was 2.97 and in 2010 is was 2.49 • May have long mains with little usage • Or big mains to potential high usage areas that never developed

23. DBPs versus Flushing • Flushing should be for more than “spot compliance” • KY regulations only recommend • But good distribution operation dictates that it should be routine practice • Scheduled, unilateral, from the plant out, water quality-based • Not just before compliance monitoring • Consider automatic flushers in areas that require more frequent turnover • And what are you basing that on??

25. In Closing…..

26. DBP Formation and Compliance • Chlorine is a good thing in water treatment • No acute, microbial-based public health concerns • So we can’t just stop chlorinating • Other disinfectants also have by-product issues • Chlorine dioxide, chloramines, ozone • Today’s source water is not getting any cleaner • And systems don’t always have another source water option

27. DBP Formation and Compliance • Today’s operators are challenged with “simultaneous compliance” • How to stay in compliance with regulations that may not work together • Then there is the Clean Water Act impacts on source water and maybe how we treat water (a whole other story) • Remember “We are all downstream” (Ecologist’s Motto)

28. DBP Formation and Compliance • We all have to work smarter not harder because we are all in this together: plant operators, distribution operators, management, engineers, regulators • Gather the data and look at it and stay ahead of the problems • Once you get the NOV, it may be too late • What are the best overall option(s) for protecting public health—not just the cheapest or the newest technology, engineering or operations • There may need to be multiple options • Communicate • Keep trying

29. Comments?? Questions?? KY Drinking Water Program Program Coordinator Compliance Technical Assistance Inspectors Capacity Development Engineering