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LT2/Stage 2 Rule

Frequent QuestionsLT2/Stage 2 Rule

I’ve been working on the Stage 2 DBPR reporting form for our district, and am looking at the compliance calculation equations for operation evaluation levels (OELs) and locational running annual averages (LRAAs). I am taking into account the compliance calculation for systems that might miss monitoring at a location. For LRAA’s, the regulation specifies calculation of LRAAs based on the available data. For OELs, the regulation specifies a formula . If a system misses monitoring for any of the previous 3 quarters, would the OEL calculation use the available data also? Another alternative would be to not calculate OELs when there is missing data. Otherwise, the OEL calculation would be biased low.
How much data needs to be grandfathered?
Are consecutive systems exempt from the requirements of the LT2 Rule?
Are IDSE results required to be reported in CCRs? If so, is this monitoring used for compliance purposes?
Are Initial Distribution System Evaluation (IDSE) submissions provided to EPA’s Information Processing and Management Center (IPMC) subject to FOIA requests?
Are systems required to conduct Stage 1 DBPR compliance monitoring concurrent with Stage 2 DBPR IDSE monitoring?
Are systems required to file a report every time an operational evaluation level is exceeded?
Are systems that received a 40/30 certification or a very small system waiver required to prepare an Initial Distribution System Evaluation (IDSE) Report and submit it to the state?
Are the CFE and IFE performance toolbox options available to all systems or only to those systems using conventional or direct filtration?
Are the combined filter performance and individual filter performance standards based on 4 hour measurements?
Are there any specific PN requirements under LT2 source water monitoring?
As established by the Long Term 2 Enhance Surface Water Treatment Rule, source water monitoring for public water systems using new surface water sources or ground water under the direct influence of surface water sources must monitor the source on a schedule approved by the state (40 CFR 141.701(f)(1)). Does monitoring have to be conducted before a new source can be used for drinking water?
As of the publication of the Stage 2 Disinfectants and Disinfections Byproducts Rule (Stage 2 DBPR), what are EPA’s conclusions for the potential association between chlorinated drinking water and adverse health effects?
Can a PWS use the same CDX username & password to access DCTS as a lab & as a PWS?
Can a system receive 40/30 certification if individual samples exceed 40/30 levels, but annual averages for TTHM and HAA5 are below these levels?
Can I start my IDSE monitoring early?
Can systems avoiding filtration receive Crypto treatment credit for a watershed control program?
Can systems on Stage 1 DBPR reduced monitoring that receive a very small system waiver remain on reduced monitoring for Stage 2 DBPR?
Can the state approve a system specific study with fewer than the number of sites required under standard monitoring?
Could you please explain: what is a dual sample set?
Do systems or states conduct the watershed sanitary survey?
Does grandfathered data for Crypto have to include E.coli and turbidity data as well, or is Crypto only sufficient?
Does increased monitoring affect the entire system or only the monitoring site that exceeded the trigger value?
Does the every 30 days mean 30 samples or one sample "every 30 days"?
During the first year of Stage 2 TTHM/HAA5 monitoring are systems required to continue conducting their Stage 1 TTHM/HAA5 monitoring until a full year of Stage 2 TTHM/HAA5 data has been collected and the first LRAA results can be calculated?
EPA Method 524.2 is an approved method for analyzing Total Trihalomethanes (TTHMs) (40 CFR 141.131(b)(1)). Must water samples being analyzed for TTHMs using EPA Method 524.2 be acidified with hydrochloric acid at the time of collection?
Filtered water systems serving fewer than 10,000 people, and not electing to sample for Cryptosporidium, must sample their source water for E. coli. at least once every two weeks for 12 months. Surface water systems sampling for E. coli will be triggered into monitoring their source water for Cryptosporidium if the annual mean E. coli concentration is greater than 10 E. coli/100mL, for systems using lake reservoir sources, or 50 E. coli/100mL, for systems using flowing stream sources. (40 CFR 141.701(a)) Can a water system exclude an extremely high, not typical, E. coli sample result that may be caused by a particular weather event such as excessive run off from a rain event?
Filtered water systems serving fewer than 10,000 people, and not electing to sample for Cryptosporidium, must sample their source water for E. coli. at least once every two weeks for 12 months. Surface water systems sampling for E. coli will be triggered into monitoring their source water for Cryptosporidium if the annual mean E. coli concentration is greater than 10 E. coli/100mL, for systems using lake reservoir sources, or 50 E. coli/100mL, for systems using flowing stream sources. (40 CFR 141.701(a)) If a single E. coli sample is extremely high and will cause the annual mean concentration to exceed the trigger levels, no matter the results of subsequent samples, can the water system stop E. coli sampling and begin Cryptosporidium monitoring?
For LT2, what are the requirements for resampling?
For LT2, what value do I use to calculate my source water average E. coli if the laboratory reports a result as less than the detection limit? What value would I report if the sample result is non-detect and a dilution factor has been applied?
For LT2, who enters lab data into DCTS, the PWS or the lab?
For Schedule 1 systems that use existing Stage 1 sites for Stage 2 compliance, does the LRAA MCL compliance begin-date start in 2nd Quarter 2012, or after 4 quarters of monitoring, same as for the new Stage 2 sampling locations?
How can a system that switches between sources seasonally sample in a way that fulfills the LT2ESWTR requirements? Will the system be locked into using both sources indefinitely?
How do I get to the DCTS and IDSE Tool?
How do I register for the DCTS as a PWS?
How do LT2 systems submit Grandfather Data?
How does Stage 2 DBPR address emergency connections?
How is compliance with the MCL's calculated in the 3 quarters leading up to the first LRAA calculations? There is a mix of sample data from Stage 1 and Stage 2 sites. Is a system wide average (like Stage 1) used for compliance during this interim period?
How is Cryptosporidium data reported in the DCTS?
How is the Bin classification calculated?
How is the population determined in order to categorize systems into the schedules? Are all the populations of the systems in a combined distribution system added together or is the schedule based on the single largest system in the combined distribution system?
How many liters should I collect for my Crypto samples?
How should a system with fewer entry points to the distribution system than the required number of samples near an entry point complete standard monitoring?
How should systems monitor during the interval between the end of IDSE monitoring and the beginning of Stage 2 DBPR compliance sampling?
How should systems with multiple entry points to the distribution system complete standard monitoring if only one sample near an entry point is required?
How would a system that intermittently disinfects comply with the Stage 2 DBPR?
How would a system that is served by both surface water and ground water sources comply with Stage 2 DBPR?
I have a utility that tells me that he has been told that he has to monitor a specific week of the month for TTHMs and HAA5s? Is this true?
I’m submitting a system specific study plan using a hydraulic model. Where do I choose my sites for one round of monitoring on the form?
If a consecutive system has multiple entry points, does a sample need to be taken at each meter?
If a single process (e.g., UV light) is conducted in series, can a system receive additional Crypto log removal credit?
If a system applies for a 40/30 certification and does not qualify, what monitoring schedule will the system be on?
If a system blends groundwater and surface water, should source water samples be collected after blending or before?
If a system commits to providing treatment instead of conducting source water monitoring, can they later decide to conduct source water monitoring?
If a system is required to take 8 high TTHM samples, can all 8 samples be taken at the same location?
If a system modifies its distribution system after completing its IDSE, is it required to complete a new IDSE?
If a treatment plant is already using membrane filtration and is placed in Bin 1, when would the system need to meet the LT2ESWTR operation and reporting requirements?
If only one site exceeds the LRAA, do we need to notify everyone in the City, or just those in the affected area?
If the combined filter effluent (CFE) and the individual filter effluent (IFE) criteria are met, can a system receive Crypto treatment credit for both?
If the main wholesale water system gets a 2-year extension, does the consecutive system also get 2-year extension?
If two plants draw from a single surface water intake, can the plants share one source water sample or must each plant collect its own sample?
Is a public water system (PWS) required to follow the Stage 2 Disinfectant/Disinfection Byproducts Rule requirements if it meets all the conditions in 40 CFR 141.3?
Is there a list of approved laboratories for analyzing Cryptosporidium under the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR)?
Is there a requirement to include Initial Distribution System Evaluation (IDSE) monitoring results for TTHMs and HAA5s in the CCR?
Must challenge testing be conducted for individual sources/systems or can it be done by a manufacturer for a specific type/quality of water?
My lab is telling me they can't enter my lab data because my system is not coming up on their screen. What's wrong?
My laboratory reported a minimum detection level (or minimum reporting level) greater than the upper limit for bin 1 (0.075 oocysts per liter). If that is the case, how can we possibly ever have our results average to less than the bin 2 level? Should we collect more volume per sample than the required 10L minimum to be able to achieve a bin 1 result?
Not all months have 30 days and not all quarters have 90 days. How will this affect compliance tracking?
On the “Unfiltered System Inactivation Requirements” slide, can the 2-log protection be provided by one disinfection method or must it come from a combination of treatment?
Once a state has primacy, is it obligated to use the Stage 2 DBPR data system?
Public water systems that filter their water and serve fewer than 10,000 people must sample their source water for E. coli (or state-approved alternate indicator, see 40 CFR 141.701(a)(5)) or notify the State that it will monitor for Cryptosporidium rather than E. coli (40 CFR 141.701(a)(3)). Systems sampling for E. coli will be required to conduct source water Cryptosporidium sampling if the annual mean concentration of their E. coli sampling is greater than 10 E. coli/100 mL, for systems using lake/reservoir sources, or greater than 50 E. coli/100 mL, for systems using flowing stream sources (40 CFR 141.701(a)(4). How is the annual mean calculated to determine if a water system, conducting E. Coli sampling, is required to conduct Cryptosporidium sampling?
Should I field filter my Cryptosporidium samples?
Should IDSE samples be collected during the warmest month or during the month of highest DBP levels?
Should results from the Initial Distribution System Evaluation (IDSE) standard monitoring required under the Stage 2 Disinfectants and Disinfection Byproducts Rule (DBPR) be used to determine compliance with maximum contaminant levels (MCLs) of the Stage 1 DBPR rule?
Should the results from the Initial Distribution System Evaluation (IDSE) standard monitoring required under the Stage 2 Disinfectants and Disinfection Byproducts Rule be included in the Consumer Confidence Report (CCR)?
Systems choosing to use membrane filtration to meet the additional Cryptosporidium treatment requirements under the Long Term 2 Enhanced Surface Water Treatment Rule (LT2) are required to conduct direct integrity tests on each membrane unit at a frequency of not less than once each day that the membrane unit is in operation (40 CFR 141.719(b)(3)(vi)). Does this mean once every 24 hours of actual filter running time, or does it mean once per calendar day regardless of runtime.
The "Amount Detected" that is reported in the CCR is based on the Running Annual Averages that are used for compliance after each quarter. A system that was complying with Stage 1 will have one or more quarters of RAAs to compare for this value. However, systems that have NOT had to comply with Stage 1 will have only Stage 2 data and there will be no compliance calculations in 2012. DOES THIS MEAN THE "AMOUNT DETECTED" FOR THESE SYSTEMS WILL BE "N/A"? I believe this is what we did when these systems were doing their IDSEs.
The Long Term 2 Enhance Surface Water Treatment Rule allows systems to receive Cryptosporidium treatment credit by meeting the conditions for one of several microbial toolbox options (40 CFR 141.715). If a water system chooses the membrane filter option, must all the water pass through the filter?
The Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) requires all public waters systems that use surface water or ground water under the direct influence of surface water to monitor their source water for Cryptosporidium (40 CFR 141.701). Are community water systems that are monitoring Cryptosporidium as part of the LT2ESWTR required to include the results in the Consumer Confidence Report?
The recovery rate of a matrix spike sample is below the quality control acceptance criteria identified in the analytical method (13% - 111%). Is the corresponding field sample valid? What steps should be taken?
Under the Stage 2 Disinfectants and Disinfection Byproducts Rule, a wholesale system or consecutive system must comply with the requirements in 40 CFR Part 141, Subpart U, at the same time as the system with the earliest compliance date in the combined distribution system, unless the state determines otherwise (40 CFR 141.600(c)). What are the definitions of wholesale system, consecutive system, and combined distribution system?
We have completed IDSE and included results in our CCR. Do these results need to stay in the CCR for 5 years or can they be removed?
We obtained a result of too numerous to count (TNTC) [or > 2419 for Colilert Quantitray analysis]. Is a resample required? How is this result entered into DCTS?
What are the different system Schedules and their population numbers?
What are the different systems schedules and their population numbers?
What are the purpose and options for the requirement in 40 CFR Part 141, Subpart U, to complete an initial distribution system evaluation (IDSE) under the Stage 2 Disinfectants and Disinfection Byproducts Rule?
What are the source water monitoring requirements of the Long Term 2 Enhanced Surface Water Treatment Rule (LT2)?
What does MRDL stand for?
What E. Coli analysis is required for source water monitoring?
What happens to a system that does not submit an IDSE plan?
What if a system’s high TTHM site and high HAA5 site are the same location?
What is CDX?
What is the definition of "finished water" as it pertains to the Stage 2 DBP Rule?
What is the detection limit for Method 1623?
What is the IDSE Tool? Can I use it?
What is the Information Processing and Management Center (IPMC)?
What is the Long Term 2/Stage 2 Data Collection and Tracking System (LT2/Stage 2 DCTS) and how do I access it?
What is the Stage2/LT2 Listserve and how do I sign up?
What is the timeline for very small system waivers?
What type of funding is available to assist systems in complying with the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) requirements?
When a required LT2 parameter for a specific sampling date (Cryptosporidium, E. coli, or turbidity) is missing, must a public water system (PWS) resample for all three parameters or only the missing parameter?
When a Schedule 3 system finishes the Stage 2 four quarters of monitoring must it continue monitoring at these sites?
When a system is submitting an IDSE plan or report to the Information Processing and Management Center (IPMC), can a system log in, work on the electronic file, log out, and come back later?
When conducting Stage 2 DBPR compliance monitoring, are all sites required to be sampled on the same day?
When creating a composite source water sample from multiple sources, assuming a blended tap is not available, what volumes must be collected from each source? Also, what should the total composite sample volume be?
When creating a monitoring schedule, are systems required to sample on a specific date, such as the 5th of each month, or can the system choose a flexible date, such as the first Monday of each month? How should a system handle weekend sampling, particularly for E. coli monitoring when the maximum holding time is 30 hours?
When determining compliance Schedules, how is a system's population served determined? Are system populations based on the wholesale system's population or the sum of the wholesale system's population and the purchased systems' population?
When do source water monitoring samples have to be submitted to EPA/State for review?
When you refer to “inactivation credits” or “log credits,” do we use the same contact time (CT) tables as for Giardia-virus removal or are there Crypto-specific CT tables?
Where can I call or email to get help with the DCTS?
Which systems are required to perform OEL evaluations? It seems this is only required for those near the MCL.
While using the IDSE Tool, I accidentally uploaded an incorrect file to the DCTS, how do I delete it?
Why are my justifications not saved in the IDSE Tool?
Why does EPA need to see my E.coli lab certification before I'm registered in DCTS?
Why is the DCTS flagging the data my lab entered?
Will a reporting violation (e.g., a system submitted its quarterly data on April 22, 12 days after the required date of April 10) make a system ineligible for a 40/30 certification?
Will systems submit sampling schedules to EPA or to the state?
Will the LT2ESWTR data system automatically calculate Bin classification?

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