1 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
2 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
3 Disinfection & Filtration 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
4 Understanding “log” removal Refers to percent of Crypto that is removed or inactivated by treatment or other measures Log% removal/inactivation 0.5-log68.4% 1-log90% 2-log99% 3-log99.9% 4-log99.99% 5-log99.999%
5 “Log” Removal Example 1 System B Both systems provide the same level of Crypto removal/inactivation, but System B provides higher quality finished water Source Water Crypto Reduction Finished Water 1 Crypto oocyst 2-log removal/ inactivation (99%) 1 Crypto oocyst System A 100,000 Crypto oocysts 100 Crypto oocysts 2-log removal/ inactivation (99%) 1,000 Crypto oocysts
6 “Log” Removal Example 2 5-log removal/ inactivation (99.999%) System B Both systems provide the same public health protection, but System A must work harder! Source Water Crypto Reduction Finished Water 1 Crypto oocyst 2-log removal/ inactivation (99%) 1 Crypto oocyst System A 100,000 Crypto oocysts 100 Crypto oocysts
7 “Log” Removal Example 3 System B 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! Source Water Crypto Reduction Finished Water 10 Crypto oocysts 2-log removal/ inactivation (99%) 1 Crypto oocyst System A 1,000 Crypto oocysts 3-log removal/ inactivation (99.9%) 1 Crypto oocyst
8 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
9 SWTRs Summary All Subpart H systems Reduce risks from Giardia lamblia & viruses SWTR (1989) Subpart H systems serving > 10,000 Address Crypto with improved treatment IESWTR (1998) Requirements similar to IESWTR applied to Subpart H systems serving < 10,000 LT1ESWTR (2002) All Subpart H systems Target additional treatment at highest-risk systems LT2ESWTR (2005) Questions? NEXT
10 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
11 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
12 Schedules If you have a Subpart H source and are this kind of system: You are on Schedule number: System serving 100,000 or more people OR a wholesale system in a CDS that contains a system serving >100,000 1 System serving 50,000 to 99,999 people OR a wholesale system in a CDS that contains a system serving 50,000 to 99,999 2 System serving 10,000 to 49,999 people OR a wholesale system in a CDS that contains a system serving 10,000 to 49,999 3 System serving fewer than 10,000 and not a wholesale system 4
13 LT2ESWTR Process Initial Round Source Water Monitoring Bin Classification Choose Toolbox Option(s) Implement Tool(s) Second Round Source Water Monitoring Bin 1 systems Small systems w/ low E. coli Systems installing max treatment Systems Subject to LT2 0
14 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 Source Water Monitoring 1
15 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 Bin & Treatment Overview 2
16 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 Toolbox Options 3
17 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 4
18 Subsequent source water monitoring 6 years after initial bin classification (filtered systems) Same requirements apply Can lead to bin reclassification Covered in future trainings Follow-Up Monitoring 5
19 Implementation Timeline Treatment installation Possible extension Crypto monitoring Schedule Crypto monitoring Treatment installation Crypto Monitoring Possible extension Schedule Treatment installation Crypto monitoring Possible extension Crypto Monitoring 3 Schedule 3
Implementation Timeline Crypt o Monitoring Treatment installation Possible extension E. coli 4 Crypt o Treatment installation Crypt o E. coli 4 Possible extension E. coli Schedule 4
21 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
22 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)
23 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
24 Source Water Sampling Schedules System Population Submit Sampling Schedule & Location Begin Monitoring > 100,000July 1, 2006Oct. 1, ,000 to 99,999Jan. 1, 2007April 1, ,000 to 49,999Jan. 1, 2008April 1, 2008 < 10,000July 1, 2008Oct. 1, 2008 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
25 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.
26 Sampling Before Chemical Treatment & Filter Backwash Recycle Sample point Filter backwash recycle (if applicable) Treatment plant Source water Chemical addition Filter backwash recycle (if applicable) Raw water intake Raw water chemical building Sample point 1 Note: Sample point 1 is BEFORE introduction of recycle Sample point 2
27 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 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.
28 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.
29 Reporting Results (cont.) What am I required to report? For Crytpo Analysis 1. PWS ID# 2. Facility ID # 3. Sample Collection Date 4. Sample Type (field or matrix spike) 5. Sample Volume Filtered (L) 6. Was 100% of filtered volume examined (yes/no) 7. Number of oocysts counted For E. Coli Analysis 1. PWS ID# 2. Facility ID # 3. Sample Collection Date 4. Analytical method # 5. Method Type 6. Source Type 7. E. Coli/100 mL 8. Turbidity (only for systems greater than 10,000)
30 Questions???? Drinking Water Program Drinking Water Program website: EPA website: