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Long Term 2 Enhanced Surface Water Treatment Rule – LT2. Mark McIntire Drinking Water Program SDWWA Water Seminar February 7, 2006. Please ask questions as we go along. Surface Water Treatment Rule Review. Source for many large systems in SD.
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Long Term 2 Enhanced Surface Water Treatment Rule – LT2 Mark McIntire Drinking Water Program SDWWA Water Seminar February 7, 2006 • Please ask questions as we go along
Surface Water Treatment Rule Review • Source for many large systems in SD. • Especially vulnerable to microbial contamination • Crypto, E. coli, and Giardia lamblia present in most surface waters
Disinfection Essential part of water treatment Creates DBPs Crypto resists traditional disinfectants Filtration Most surface water systems filter Key barrier against microbial contamination Physical process can remove Crypto Disinfection still necessary Disinfection & Filtration
Understanding “log” removal • Refers to percent of Crypto that is removed or inactivated by treatment or other measures
System B “Log” Removal Example 1 System A Source Water 100 Crypto oocysts 100,000 Crypto oocysts 2-log removal/ inactivation (99%) 2-log removal/ inactivation (99%) Crypto Reduction Finished Water 1 Crypto oocyst 1 Crypto oocyst 1,000 Crypto oocysts Both systems provide the same level of Crypto removal/inactivation, but System B provides higher quality finished water
5-log removal/ inactivation (99.999%) System B “Log” Removal Example 2 System A Source Water 100 Crypto oocysts 100,000 Crypto oocysts 2-log removal/ inactivation (99%) Crypto Reduction Finished Water 1 Crypto oocyst 1 Crypto oocyst Both systems provide the same public health protection, but System A must work harder!
System B “Log” Removal Example 3 System A Source Water 1,000 Crypto oocysts 1,000 Crypto oocysts 3-log removal/ inactivation (99.9%) 2-log removal/ inactivation (99%) Crypto Reduction Finished Water 1 Crypto oocyst 10 Crypto oocysts 1 Crypto oocyst System A and B have the same source water Crypto level but System A provides a greater level of removal/inactivation, resulting in higher quality finished water!
M-DBP History • LT2ESWTR (2006) • Improves microbial protection • Builds on SWTR, IESWTR, & LT1ESWTR • Does not change any existing requirements from SWTR suite • Flexible, risk-based rule based on new Crypto data • The amount of Crypto detected in the source water determines the additional levels of required treatment
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 (2005) • All Subpart H systems • Target additional treatment at highest-risk systems SWTRs Summary NEXT Questions?
Purposes of the LT2ESWTR • Improve public health protection • Reduce illness caused by Crypto and other microorganisms • Tailor requirements based on: • Level of treatment • Source water quality • System size • Provide systems and states with flexibility • Most systems will only need to monitor
Applicability • All Subpart H systems • Use surface water or GWUDI sources • CWSs, NTNCWSs, TNCWSs • Wholesale systems • Compliance deadlines and options based on number of people served • Divided into four schedules • Wholesale systems with own Subpart H source(s) comply based on population of largest system in their CDS
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
1 Source Water Monitoring • Requirements based on: • System size • Wholesale status • Source water • Operating calendar • Initial round • Start date based on system size • For wholesale systems, based on largest system in CDS • Grandfathering is permitted
2 Bin & Treatment Overview • Filtered PWSs are classified into one of four bins • Based on initial monitoring results • May set additional requirements • Bin 1: no additional treatment • Bins 2, 3, 4: additional treatment or control processes • Covered in future trainings
3 Toolbox Options • Range of treatment and control process options to meet bin requirements: • Source protection and management • Prefiltration • Treatment performance • Additional filtration • Inactivation* • Offer Crypto treatment credits • Options discussed in depth at future trainings * Unfiltered systems are limited to these tools
4 Implement Option(s) • Install chosen treatment to meet bin requirements: • Schedule 1 – April 1, 2012 • Schedule 2 – October 1, 2012 • Schedule 3 – October 1, 2013 • Schedule 4 – October 1, 2014 • State can allow up to 2 additional years • Covered in future trainings
5 Follow-Up Monitoring • Subsequent source water monitoring • 6 years after initial bin classification (filtered systems) • Same requirements apply • Can lead to bin reclassification • Covered in future trainings
Schedule Schedule 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Treatment installation Possible extension Crypto monitoring Crypto monitoring 2 3 1 1 2 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Crypto monitoring Treatment installation Possible extension Crypto Monitoring Schedule 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 Crypto monitoring Treatment installation Possible extension Crypto Monitoring 3 Implementation Timeline
E. coli E. coli 4 4 E. coli Crypto Treatment installation Possible extension E. coli Crypto Treatment installation E. coli Crypto Monitoring Possible extension E. coli Crypto 4 4 Implementation Timeline Schedule 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Profiling and Benchmarking • Balance risks between microbial pathogens and DBPs • Impact of Stage 2 DBPR and Crypto requirements • Required when altering disinfection • Develop profile for Giardia lamblia and viruses • Calculate benchmark • Requirements go into effect upon completion of initial monitoring
Source Water Sampling • Source Water Monitoring • For systems using surface water and serving 10,000 people or more • Must monitor for Crypto, E. Coli and turbidity once a month for 24 months • Seasonal systems must collect at least 6 samples evenly spaced through months of operation • Systems using surface water and serving less than 10,000 people (Schedule 4 system) must monitor for E. coli once every 2 weeks for 12 months, However (next slide)
Source Water Sampling (cont.) • Systems less than 10,000 people using lake or reservoir sources • If the annual mean E. coli concentration is greater than 10 E. coli per 100 mL, the system must collect 24 Crypto samples in either one or two years • Systems less than 10,000 people using flowing stream sources • If the annual mean E. coli concentration is greater than 50 E. coli per 100 mL, the system must collect 24 Crypto samples in either one or two years
Source Water Sampling Schedules • Systems must submit to State or CDX a sampling schedule that specifies the calendar dates when the system will collect each required sample, 3 months prior to start of sampling • Systems must collect the samples within two days before or two days after the dates indicated in their sampling schedule
Source Water Sampling Locations • Where do I collect my sample? • Systems must submit a description of their sampling location to the State or DCTS at the same time as the sampling schedule is required to be submitted. • Systems must collect source water samples (crypto, E. Coli and turbidity) prior to any chemical treatment. • Systems that recycle filter backwash water must collect source samples prior to the point of filter backwash addition.
Sample point 2 Sampling Before Chemical Treatment & Filter Backwash Recycle Sample point Raw water intake Source water Treatment plant Filter backwash recycle(if applicable) Raw water chemical building Note: Sample point 1 is BEFORE introduction of recycle Sample point 1 Chemicaladdition Filter backwash recycle(if applicable)
Approved Laboratories • Crypto and E. Coli sample analysis must be performed at EPA approved laboratories • Crypto samples must be sent to a lab from the list found on this EPA Website http://www.epa.gov/ogwdw/disinfection/lt2/lab_aprvlabs.html • E. Coli samples for this monitoring must be counts (enumeration), not just presence/absence like routine monthly sampling • Most labs in SD should be able to do this, but ask them first • Also make sure that when you submit samples, the lab sheets indicate that you want E. Coli counts not P/A • Turbidity – the system is allowed to take their own turbidity. • Make sure your turbidimeter has been calibrated according to manufacturers specifications.
Reporting Results • Systems must report results from source water monitoring no later than 10 days after the end of the first month following the month when the sample is collected • EPA should be contacting all systems with a letter telling you how to access the CDX system. • Systems serving at least 10,000 people must submit the results electronically through EPA’s CDX system. • Hopefully the labs will be able to submit the results for you. • Make sure you fill out the lab sheets completely. • Systems serving less than 10,000 will be allowed to submit their source water data directly to the state. However, if the system registers in the CDX system, they may be able to get the labs to submit their results for them.
Reporting Results (cont.) What am I required to report? For E. Coli Analysis • PWS ID# • Facility ID # • Sample Collection Date • Analytical method # • Method Type • Source Type • E. Coli/100 mL • Turbidity (only for systems greater than 10,000) For Crytpo Analysis • PWS ID# • Facility ID # • Sample Collection Date • Sample Type (field or matrix spike) • Sample Volume Filtered (L) • Was 100% of filtered volume examined (yes/no) • Number of oocysts counted
Questions???? • Drinking Water Program 773-3754 • Drinking Water Program website: • http://www.state.sd.us/denr/dw • EPA website: • http://www.epa.gov/OGWDW/