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1. 1 Long Term 2 Enhanced Surface Water Treatment Rule LT2 Mark McIntire
Drinking Water Program
SDWWA Water Seminar
February 7, 2006
2. 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 Surface water includes all water that is open to the atmosphere and subject to surface runoff. This water, which most of the country's large water systems use, includes rivers, lakes, and reservoirs. Surface water is particularly susceptible to microbial contamination from sewage treatment plant discharges and runoff from storm water and snow melt.
Disease-causing microbes such as Crypto, E. coli, and Giardia lamblia are present at varying concentrations in most surface water. The concentration can be much greater after a high rain event due to runoff. Two common sources of microbial contaminants include livestock wastes and septic systems.
EPA has responded to the heightened threat and increased awareness of microbial contamination of surface water sources through a series of rules targeting surface water and GWUDI sources, beginning with the SWTR in 1989. The step-approach to regulating surface water sources reflects the progress of EPAs understanding of surface water contamination.
Surface water includes all water that is open to the atmosphere and subject to surface runoff. This water, which most of the country's large water systems use, includes rivers, lakes, and reservoirs. Surface water is particularly susceptible to microbial contamination from sewage treatment plant discharges and runoff from storm water and snow melt.
Disease-causing microbes such as Crypto, E. coli, and Giardia lamblia are present at varying concentrations in most surface water. The concentration can be much greater after a high rain event due to runoff. Two common sources of microbial contaminants include livestock wastes and septic systems.
EPA has responded to the heightened threat and increased awareness of microbial contamination of surface water sources through a series of rules targeting surface water and GWUDI sources, beginning with the SWTR in 1989. The step-approach to regulating surface water sources reflects the progress of EPAs understanding of surface water contamination.
3. 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 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 throughout American cities. Disinfection was a major factor in reducing these epidemics, and it is an essential part of drinking water treatment today. However, the disinfectants themselves can react with naturally-occurring materials in the water to form unintended organic and inorganic byproducts which may pose health risks.
In addition, data have become available over the past 10 years showing that specific microbial pathogens, such as Crypto, are highly resistant to traditional disinfection practices. In 1993, Cryptosporidium caused 400,000 people in Milwaukee to experience intestinal illness. More than 4,000 were hospitalized, and at least 50 deaths have been attributed to the disease. There have also been cryptosporidiosis outbreaks in Nevada, Oregon, and Georgia over the past several years. However, alternative disinfection practices such as UV, ozone, and chlorine dioxide are proving effective at treating Crypto in source waters.
Because surface water sources are especially vulnerable to microbial contamination, the majority of water systems using surface water sources use a form of physical filtration to provide an extra barrier against microbial contamination and meet regulatory requirements.
Some public water supplies that have pristine sources may be granted a waiver from the filtration requirement. These supplies must provide the same level of treatment as those that filter; however, their treatment is provided through disinfection alone. The LT2ESWTR ensures that these unfiltered systems continue to provide adequate protection against microbial contamination.
Disinfection is still necessary to provide adequate microbial protection in the distribution system. Surface water systems are required to provide continuous disinfection of the drinking water entering the distribution system and to maintain a detectable disinfectant level within the distribution system. The Stage 1 and Stage 2 Disinfectant and Disinfection Byproduct Rules (DBPRs) help ensure that the DBPs formed by the disinfection process do not pose additional public health risks.
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 throughout American cities. Disinfection was a major factor in reducing these epidemics, and it is an essential part of drinking water treatment today. However, the disinfectants themselves can react with naturally-occurring materials in the water to form unintended organic and inorganic byproducts which may pose health risks.
In addition, data have become available over the past 10 years showing that specific microbial pathogens, such as Crypto, are highly resistant to traditional disinfection practices. In 1993, Cryptosporidium caused 400,000 people in Milwaukee to experience intestinal illness. More than 4,000 were hospitalized, and at least 50 deaths have been attributed to the disease. There have also been cryptosporidiosis outbreaks in Nevada, Oregon, and Georgia over the past several years. However, alternative disinfection practices such as UV, ozone, and chlorine dioxide are proving effective at treating Crypto in source waters.
Because surface water sources are especially vulnerable to microbial contamination, the majority of water systems using surface water sources use a form of physical filtration to provide an extra barrier against microbial contamination and meet regulatory requirements.
Some public water supplies that have pristine sources may be granted a waiver from the filtration requirement. These supplies must provide the same level of treatment as those that filter; however, their treatment is provided through disinfection alone. The LT2ESWTR ensures that these unfiltered systems continue to provide adequate protection against microbial contamination.
Disinfection is still necessary to provide adequate microbial protection in the distribution system. Surface water systems are required to provide continuous disinfection of the drinking water entering the distribution system and to maintain a detectable disinfectant level within the distribution system. The Stage 1 and Stage 2 Disinfectant and Disinfection Byproduct Rules (DBPRs) help ensure that the DBPs formed by the disinfection process do not pose additional public health risks.
4. 4 Understanding log removal Refers to percent of Crypto that is removed or inactivated by treatment or other measures
Throughout this training, you will see reference to log removal. For this training, log refers to the percentage of Crypto that treatment or other measures remove or inactivate. 0.5-log is equivalent to 68.4% removal/inactivation; 1-log is equivalent to 90%; 2-log is equivalent to 99%; 3-log is equivalent to 99.9%; 4-log is equivalent to 99.99%; 5-log is equivalent to 99.999%.
Throughout this training, you will see reference to log removal. For this training, log refers to the percentage of Crypto that treatment or other measures remove or inactivate. 0.5-log is equivalent to 68.4% removal/inactivation; 1-log is equivalent to 90%; 2-log is equivalent to 99%; 3-log is equivalent to 99.9%; 4-log is equivalent to 99.99%; 5-log is equivalent to 99.999%.
5. 5 Log Removal Example 1 System B This example shows System A using source water from an unprotected source and System B using water from a more pristine source. Both systems provide 2-log treatment, but because of their different quality source water, System As finished water has 1,000 Crypto oocysts per unit, while System Bs finished water has only 1 Crypto oocyst per unit.
This example shows System A using source water from an unprotected source and System B using water from a more pristine source. Both systems provide 2-log treatment, but because of their different quality source water, System As finished water has 1,000 Crypto oocysts per unit, while System Bs finished water has only 1 Crypto oocyst per unit.
6. 6 Log Removal Example 2 5-log removal/ inactivation (99.999%) System B It is possible for two water systems with the same finished water concentration of Crypto to begin with very different source water concentrations, as shown in this example. System As source water comes from an unprotected source, and System Bs source water comes from a more pristine source. The systems, therefore, have different source water Crypto levels. While both systems have finished water levels of 1 Crypto oocyst per unit, System A has to provide a higher degree of treatment.It is possible for two water systems with the same finished water concentration of Crypto to begin with very different source water concentrations, as shown in this example. System As source water comes from an unprotected source, and System Bs source water comes from a more pristine source. The systems, therefore, have different source water Crypto levels. While both systems have finished water levels of 1 Crypto oocyst per unit, System A has to provide a higher degree of treatment.
7. 7 Log Removal Example 3 System B In this final example, System A is able to produce higher quality finished water than System B, even though Systems A and B have the same source water Crypto level. System A provides 3-log removal/inactivation, resulting in a finished water Crypto level of 1 oocyst per unit. System B provides 2-log removal/inactivation, resulting in a finished water Crypto level of 10 oocysts per unit.
Discussion: Does anyone have an example of a similar situation with real systems?In this final example, System A is able to produce higher quality finished water than System B, even though Systems A and B have the same source water Crypto level. System A provides 3-log removal/inactivation, resulting in a finished water Crypto level of 1 oocyst per unit. System B provides 2-log removal/inactivation, resulting in a finished water Crypto level of 10 oocysts per unit.
Discussion: Does anyone have an example of a similar situation with real systems?
8. 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
Important Speakers Note: If you think your audience needs additional information about the history of the SWTR suite, you will find additional slides on the CD.
The LT2ESWTR builds on, rather than replaces, the requirements of the SWTR, IESWTR, and the LT1ESWTR. It is intended to improve control of microbial pathogens by requiring monitoring and, if necessary, treatment for Crypto. The LT2ESWTR does not change any of the existing requirements of the SWTR suite. Systems still need to ensure that the concentration of disinfectant at the entry point to the system is at least 0.2 mg/L and detectable in the distribution system. In addition, systems still need to provide 4-log and 3-log inactivation/removal of viruses and Giardia respectively as well as at least 2-log removal of Crypto. Finally, systems must continue to meet their CFE and IFE requirements.
Since multiple threats require multiple approaches, the LT2ESWTR and Stage 2 DBPR expand on the foundation of previous M-DBP Rules to target health risks not addressed by prior regulations. By encompassing these previously unaddressed health risks from microbials and DBPs, the M-DBP Suite continues to maximize drinking water quality and public health protection.
Important Speakers Note: If you think your audience needs additional information about the history of the SWTR suite, you will find additional slides on the CD.
The LT2ESWTR builds on, rather than replaces, the requirements of the SWTR, IESWTR, and the LT1ESWTR. It is intended to improve control of microbial pathogens by requiring monitoring and, if necessary, treatment for Crypto. The LT2ESWTR does not change any of the existing requirements of the SWTR suite. Systems still need to ensure that the concentration of disinfectant at the entry point to the system is at least 0.2 mg/L and detectable in the distribution system. In addition, systems still need to provide 4-log and 3-log inactivation/removal of viruses and Giardia respectively as well as at least 2-log removal of Crypto. Finally, systems must continue to meet their CFE and IFE requirements.
Since multiple threats require multiple approaches, the LT2ESWTR and Stage 2 DBPR expand on the foundation of previous M-DBP Rules to target health risks not addressed by prior regulations. By encompassing these previously unaddressed health risks from microbials and DBPs, the M-DBP Suite continues to maximize drinking water quality and public health protection.
9. 9 SWTRs Summary This module discussed the need for regulatory oversight of surface water systems in particular, the roles of disinfection and filtration, and the balance between providing adequate disinfection and controlling the creation of harmful DBPs. The module also provided an overview of the Rules that make up the M-DBP Suite.
The four Surface Water Treatment Rules were developed in response to the 1986 and 1996 Congressional mandates (SDWA Amendments) and represent a progression in an understanding of the risks of microbial contamination. Since the promulgation of the 1989 SWTR, new scientific data has provided a more complete picture of what sources are at the greatest risk for microbial contamination and the effectiveness of treatment for microbial contaminant removal.
The original SWTR focused on reducing the risk of contamination from Giardia lamblia and viruses and applied to all Subpart H systems. The 1998 Interim Enhanced Surface Water Treatment Rule (IESWTR) broadened regulatory focus with the goal of optimizing treatment reliability and to enhance physical removal efficiencies to minimize the Crypto levels in finished water. The Rule also includes disinfection benchmark provisions to ensure continued levels of microbial protection while facilities take the necessary steps to comply with the Stage 1 DBPR standards. The Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) broadened IESWTR applicability to Subpart H systems of all sizes.
Finally, the LT2ESWTR takes into account new scientific data on Crypto occurrence. The Rule is designed to reduce disease incidence associated with Crypto and other pathogenic microorganisms. The LT2ESWTR will supplement the existing SWTRs by targeting additional Crypto treatment requirements to higher risk systems and mitigating risks from uncovered finished water storage facilities. The Rule will also continue to ensure that systems maintain microbial protection as they take steps to reduce the formation of DBPs.
DISCUSSION: Do attendees have any observations that they would like to offer about the M-DBP rules? Have they been successful in your state(s)? Have they improved public health protection in spite of initial skepticism? Have systems been receptive to the new requirements?This module discussed the need for regulatory oversight of surface water systems in particular, the roles of disinfection and filtration, and the balance between providing adequate disinfection and controlling the creation of harmful DBPs. The module also provided an overview of the Rules that make up the M-DBP Suite.
The four Surface Water Treatment Rules were developed in response to the 1986 and 1996 Congressional mandates (SDWA Amendments) and represent a progression in an understanding of the risks of microbial contamination. Since the promulgation of the 1989 SWTR, new scientific data has provided a more complete picture of what sources are at the greatest risk for microbial contamination and the effectiveness of treatment for microbial contaminant removal.
The original SWTR focused on reducing the risk of contamination from Giardia lamblia and viruses and applied to all Subpart H systems. The 1998 Interim Enhanced Surface Water Treatment Rule (IESWTR) broadened regulatory focus with the goal of optimizing treatment reliability and to enhance physical removal efficiencies to minimize the Crypto levels in finished water. The Rule also includes disinfection benchmark provisions to ensure continued levels of microbial protection while facilities take the necessary steps to comply with the Stage 1 DBPR standards. The Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) broadened IESWTR applicability to Subpart H systems of all sizes.
Finally, the LT2ESWTR takes into account new scientific data on Crypto occurrence. The Rule is designed to reduce disease incidence associated with Crypto and other pathogenic microorganisms. The LT2ESWTR will supplement the existing SWTRs by targeting additional Crypto treatment requirements to higher risk systems and mitigating risks from uncovered finished water storage facilities. The Rule will also continue to ensure that systems maintain microbial protection as they take steps to reduce the formation of DBPs.
DISCUSSION: Do attendees have any observations that they would like to offer about the M-DBP rules? Have they been successful in your state(s)? Have they improved public health protection in spite of initial skepticism? Have systems been receptive to the new requirements?
10. 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 In the LT2ESWTR, EPA is addressing a number of public health concerns that remain following implementation of the Interim Enhanced Surface Water Treatment Rule (IESWTR) and Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR), including:
The need for filtered public water systems (PWSs) with higher levels of source water Crypto contamination to provide additional risk-based treatment for Crypto beyond the IESWTR or LT1ESWTR requirements;
The need for unfiltered PWSs to provide risk-based treatment for Crypto to achieve equivalent public health protection with filtered PWSs; and,
The need for PWSs with uncovered finished water storage facilities to take steps to reduce the risk of contamination of treated water prior to distribution to consumers.
The Rule is designed to protect public health by lowering the level of Crypto in finished drinking water to less than 1 oocyst/10,000 L while maintaining public health protection against DBP-related risks (parallel protection is ensured through the simultaneous promulgation of the Stage 2 DBPR).
Current requirements set by the preceding Surface Water Treatment Rules (including 2-log Crypto removal for filtered systems and watershed control programs that minimize the risk of Crypto contamination for unfiltered systems) are adequate for the majority of systems. A subset of PWSs with greater vulnerability to Crypto, however, requires additional treatment. This includes:
Filtered systems with high source water Crypto levels.
Unfiltered systems with high finished water Crypto levels.
Systems with uncovered finished water storage facilities.
New data also indicate the effectiveness of alternative treatment technologies in reducing finished water Crypto levels, including UV, ozone, and chlorine dioxide.
Other effective practices include watershed management programs, pretreatment processes, and additional clarification and filtration processes. These treatments and practices are incorporated in the LT2ESWTRs microbial toolbox, which are discussed briefly later in this module and in detail in future trainings.
The LT2ESWTR is flexible because it targets systems with the greatest public health risks and gives them ample choices in how to address these risks.
In addition to improving public health, the data gathered by systems under the initial monitoring phase will help EPA to determine if the SWTRs need to be changed in the future. EPA anticipates that most systems will only need to monitor their source water to comply with the LT2ESWTR.
Finally, the LT2ESWTR is being released concurrently with the Stage 2 DBPR to ensure that the risks from DBPs are adequately balanced against the need for disinfection.In the LT2ESWTR, EPA is addressing a number of public health concerns that remain following implementation of the Interim Enhanced Surface Water Treatment Rule (IESWTR) and Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR), including:
The need for filtered public water systems (PWSs) with higher levels of source water Crypto contamination to provide additional risk-based treatment for Crypto beyond the IESWTR or LT1ESWTR requirements;
The need for unfiltered PWSs to provide risk-based treatment for Crypto to achieve equivalent public health protection with filtered PWSs; and,
The need for PWSs with uncovered finished water storage facilities to take steps to reduce the risk of contamination of treated water prior to distribution to consumers.
The Rule is designed to protect public health by lowering the level of Crypto in finished drinking water to less than 1 oocyst/10,000 L while maintaining public health protection against DBP-related risks (parallel protection is ensured through the simultaneous promulgation of the Stage 2 DBPR).
Current requirements set by the preceding Surface Water Treatment Rules (including 2-log Crypto removal for filtered systems and watershed control programs that minimize the risk of Crypto contamination for unfiltered systems) are adequate for the majority of systems. A subset of PWSs with greater vulnerability to Crypto, however, requires additional treatment. This includes:
Filtered systems with high source water Crypto levels.
Unfiltered systems with high finished water Crypto levels.
Systems with uncovered finished water storage facilities.
New data also indicate the effectiveness of alternative treatment technologies in reducing finished water Crypto levels, including UV, ozone, and chlorine dioxide.
Other effective practices include watershed management programs, pretreatment processes, and additional clarification and filtration processes. These treatments and practices are incorporated in the LT2ESWTRs microbial toolbox, which are discussed briefly later in this module and in detail in future trainings.
The LT2ESWTR is flexible because it targets systems with the greatest public health risks and gives them ample choices in how to address these risks.
In addition to improving public health, the data gathered by systems under the initial monitoring phase will help EPA to determine if the SWTRs need to be changed in the future. EPA anticipates that most systems will only need to monitor their source water to comply with the LT2ESWTR.
Finally, the LT2ESWTR is being released concurrently with the Stage 2 DBPR to ensure that the risks from DBPs are adequately balanced against the need for disinfection.
11. 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 The LT2ESWTR applies to all Subpart H systems, which are systems using surface water or GWUDI sources.
Wholesale PWSs must comply with the rule based on the population of the largest PWS in their CDS.
The Rule applies to systems of all sizes. The Rule divides systems into several size categories (described in detail on the following slide), which are referred to as schedules, for purposes of staggering compliance deadlines.
Both filtered and unfiltered systems must comply, though requirements vary according to filtration status.
The LT2ESWTR applies to all Subpart H systems, which are systems using surface water or GWUDI sources.
Wholesale PWSs must comply with the rule based on the population of the largest PWS in their CDS.
The Rule applies to systems of all sizes. The Rule divides systems into several size categories (described in detail on the following slide), which are referred to as schedules, for purposes of staggering compliance deadlines.
Both filtered and unfiltered systems must comply, though requirements vary according to filtration status.
12. 12 Schedules EPA has established four schedule categories. The schedule categories were established to simplify the discussion of the LT2ESWTR requirements.
EPA has established four schedule categories. The schedule categories were established to simplify the discussion of the LT2ESWTR requirements.
13. 13 LT2ESWTR Process The LT2ESWTR compliance process involves five steps.
First, systems must conduct initial source water monitoring. Crypto source water monitoring will determine the Crypto risk level for systems. (Though not discussed in depth in this training, Schedule 4 systems may also be conducting E. coli monitoring at this point to determine whether or not Crypto monitoring is necessary, as discussed on the previous slide). Systems can choose to forgo monitoring in favor of installing maximum treatment (i.e., 5.5-log) for Crypto (skipping to Step 3).
Under the second step, systems are classified into bins, based on their initial source water monitoring results. Bin classification determines whether the system will be required to provide additional treatment for Crypto and, if so, how much treatment.
Third, systems that are required to increase their current levels of Crypto treatment must choose from a variety of options (organized in a microbial toolbox).
Fourth, systems will implement their chosen tool(s).
Note that systems that are classified in Bin 1 are not required to meet the requirements of the third and fourth steps. The requirements associated with each bin will be discussed in more detail in future trainings.
Finally, systems will conduct a second round of source water monitoring in order to determine whether bin reclassification is necessary. This will take place either 6 years after bin classification (filtered systems) or 6 years after the determination of mean Crypto levels (unfiltered systems).
The LT2ESWTR compliance process involves five steps.
First, systems must conduct initial source water monitoring. Crypto source water monitoring will determine the Crypto risk level for systems. (Though not discussed in depth in this training, Schedule 4 systems may also be conducting E. coli monitoring at this point to determine whether or not Crypto monitoring is necessary, as discussed on the previous slide). Systems can choose to forgo monitoring in favor of installing maximum treatment (i.e., 5.5-log) for Crypto (skipping to Step 3).
Under the second step, systems are classified into bins, based on their initial source water monitoring results. Bin classification determines whether the system will be required to provide additional treatment for Crypto and, if so, how much treatment.
Third, systems that are required to increase their current levels of Crypto treatment must choose from a variety of options (organized in a microbial toolbox).
Fourth, systems will implement their chosen tool(s).
Note that systems that are classified in Bin 1 are not required to meet the requirements of the third and fourth steps. The requirements associated with each bin will be discussed in more detail in future trainings.
Finally, systems will conduct a second round of source water monitoring in order to determine whether bin reclassification is necessary. This will take place either 6 years after bin classification (filtered systems) or 6 years after the determination of mean Crypto levels (unfiltered systems).
14. 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 The initial source water monitoring requirements are the focus of this training.
When, how often, and for how long systems must conduct initial source water monitoring depends on system size, its source water, whether the system is a wholesale system, whether or not it has filtration in place, and whether it operates year-round.
System size, wholesale status, and filtration status also determine the contaminant(s) for which the system must monitor.
Systems will conduct an initial monitoring round following promulgation of the LT2ESWTR to determine what, if any, additional treatment requirements apply to the system. Start dates are staggered according to system size. Wholesale systems must comply based on the requirements of the largest system in the combined distribution system.
With approval from EPA or the state, PWSs may comply with the initial source water monitoring requirements by using sample results collected before the PWS is required to begin monitoring (i.e., grandfathering). PWSs may grandfather monitoring results either in lieu of or in addition to conducting new monitoring under the Rule. The initial source water monitoring requirements are the focus of this training.
When, how often, and for how long systems must conduct initial source water monitoring depends on system size, its source water, whether the system is a wholesale system, whether or not it has filtration in place, and whether it operates year-round.
System size, wholesale status, and filtration status also determine the contaminant(s) for which the system must monitor.
Systems will conduct an initial monitoring round following promulgation of the LT2ESWTR to determine what, if any, additional treatment requirements apply to the system. Start dates are staggered according to system size. Wholesale systems must comply based on the requirements of the largest system in the combined distribution system.
With approval from EPA or the state, PWSs may comply with the initial source water monitoring requirements by using sample results collected before the PWS is required to begin monitoring (i.e., grandfathering). PWSs may grandfather monitoring results either in lieu of or in addition to conducting new monitoring under the Rule.
15. 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 Bin classification will be covered in-depth in future trainings.
Filtered PWSs will be classified in one of four treatment categories (bins) based on the results of the source water Crypto monitoring.
Bin classification determines the degree of additional Crypto treatment, if any, the filtered PWS must provide.
Occurrence data indicate that most filtered PWSs will be classified in Bin 1, which carries no additional treatment requirements.
PWSs classified in Bins 2, 3, or 4 must achieve an additional 1.0- to 2.5-log of treatment (i.e., 90 to 99.7 percent reduction) for Crypto over and above the 2-log removal currently provided.
Unfiltered systems treatment requirements are based on the results of their initial source water monitoring:
Unfiltered systems with a mean Crypto level of 0.01 oocysts/L or less must provide at least 2-log Crypto inactivation.
Unfiltered systems with a mean Crypto level of greater than 0.01 oocysts/L must provide at least 3-log Crypto inactivation.
This must be accomplished using a minimum of two disinfectants.Bin classification will be covered in-depth in future trainings.
Filtered PWSs will be classified in one of four treatment categories (bins) based on the results of the source water Crypto monitoring.
Bin classification determines the degree of additional Crypto treatment, if any, the filtered PWS must provide.
Occurrence data indicate that most filtered PWSs will be classified in Bin 1, which carries no additional treatment requirements.
PWSs classified in Bins 2, 3, or 4 must achieve an additional 1.0- to 2.5-log of treatment (i.e., 90 to 99.7 percent reduction) for Crypto over and above the 2-log removal currently provided.
Unfiltered systems treatment requirements are based on the results of their initial source water monitoring:
Unfiltered systems with a mean Crypto level of 0.01 oocysts/L or less must provide at least 2-log Crypto inactivation.
Unfiltered systems with a mean Crypto level of greater than 0.01 oocysts/L must provide at least 3-log Crypto inactivation.
This must be accomplished using a minimum of two disinfectants.
16. 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 Microbial toolbox refers to the range of treatment and control processes that systems can use to meet their additional Crypto treatment requirements determined by their bin classification. These options will be discussed in-depth at future trainings.
There are five categories of toolbox options, each of which includes a number of options for which systems can receive Crypto treatment credit. The categories are:
Source protection and management (watershed control programs and alternative source/intake management);
Prefiltration (presedimentation basin with coagulation, two-stage lime softening, and bank filtration);
Treatment performance (combined filter performance, individual filter performance, and demonstration of performance);
Additional filtration (bag and cartridge filters, membrane filtration, second stage filtration, and slow sand filters); and,
Inactivation (chlorine dioxide, ozone, and UV). This is the only option for unfiltered systems.
Depending on the treatment(s) or control process option(s) that a system implements, it will receive a certain amount of credit for Crypto treatment. For example, implementing a watershed control program gives a system a 0.5 log treatment credit.
Unfiltered systems must only use inactivation tools, chlorine dioxide, ozone, or UV to meet their Crypto inactivation requirements.Microbial toolbox refers to the range of treatment and control processes that systems can use to meet their additional Crypto treatment requirements determined by their bin classification. These options will be discussed in-depth at future trainings.
There are five categories of toolbox options, each of which includes a number of options for which systems can receive Crypto treatment credit. The categories are:
Source protection and management (watershed control programs and alternative source/intake management);
Prefiltration (presedimentation basin with coagulation, two-stage lime softening, and bank filtration);
Treatment performance (combined filter performance, individual filter performance, and demonstration of performance);
Additional filtration (bag and cartridge filters, membrane filtration, second stage filtration, and slow sand filters); and,
Inactivation (chlorine dioxide, ozone, and UV). This is the only option for unfiltered systems.
Depending on the treatment(s) or control process option(s) that a system implements, it will receive a certain amount of credit for Crypto treatment. For example, implementing a watershed control program gives a system a 0.5 log treatment credit.
Unfiltered systems must only use inactivation tools, chlorine dioxide, ozone, or UV to meet their Crypto inactivation requirements.
17. 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
The LT2ESWTR specifies the dates by which systems must have their chosen microbial toolbox options in place. Schedule 1 systems (serving 100,000 or more people) must have their tool(s) in place by April 1, 2012; Schedule 2 systems (serving 50,000 99,999 people) have until October 1, 2012; and Schedule 3 systems (serving 10,000 49,999 people) have until October 1, 2013. States may give systems up to an additional 2 years to install treatment.
This step will be discussed in more detail in future trainings.The LT2ESWTR specifies the dates by which systems must have their chosen microbial toolbox options in place. Schedule 1 systems (serving 100,000 or more people) must have their tool(s) in place by April 1, 2012; Schedule 2 systems (serving 50,000 99,999 people) have until October 1, 2012; and Schedule 3 systems (serving 10,000 49,999 people) have until October 1, 2013. States may give systems up to an additional 2 years to install treatment.
This step will be discussed in more detail in future trainings.
18. 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 A second round of source water monitoring will determine if there has been a significant change in source water quality that would affect treatment requirements. This will take place either 6 years after bin classification (filtered systems) or 6 years after the determination of mean Crypto levels (unfiltered systems). These requirements will be discussed in-depth at future trainings.
If EPA does not modify the LT2ESWTR requirements by issuing a new regulation prior to the second round of monitoring, systems must monitor according to the requirements that apply to the initial round of source water monitoring.
Based on this set of results, systems may be reclassified in the LT2ESWTR treatment bins. If EPA changes the LT2ESWTR treatment bin structure to reflect a new analytical method or new risk information, systems may need to undergo a site-specific risk characterization in accordance with the revised rule.
A second round of source water monitoring will determine if there has been a significant change in source water quality that would affect treatment requirements. This will take place either 6 years after bin classification (filtered systems) or 6 years after the determination of mean Crypto levels (unfiltered systems). These requirements will be discussed in-depth at future trainings.
If EPA does not modify the LT2ESWTR requirements by issuing a new regulation prior to the second round of monitoring, systems must monitor according to the requirements that apply to the initial round of source water monitoring.
Based on this set of results, systems may be reclassified in the LT2ESWTR treatment bins. If EPA changes the LT2ESWTR treatment bin structure to reflect a new analytical method or new risk information, systems may need to undergo a site-specific risk characterization in accordance with the revised rule.
19. 19 Implementation Timeline This slide presents a timeline of the key milestones in the rule implementation process for Schedule 1, 2, and 3 systems. The first row displays requirements for Schedule 1 systems (100,000 or more people). The second row displays requirements for Schedule 2 systems (50,000 to 99,999 people). The third row displays requirements for Schedule 3 systems (10,000 to 49,999 people). The focus of this training is on the Schedule 1, 2, and 3 systems because of the nearness of their compliance deadlines. Key milestones for Schedule 4 systems are presented in the next slide.This slide presents a timeline of the key milestones in the rule implementation process for Schedule 1, 2, and 3 systems. The first row displays requirements for Schedule 1 systems (100,000 or more people). The second row displays requirements for Schedule 2 systems (50,000 to 99,999 people). The third row displays requirements for Schedule 3 systems (10,000 to 49,999 people). The focus of this training is on the Schedule 1, 2, and 3 systems because of the nearness of their compliance deadlines. Key milestones for Schedule 4 systems are presented in the next slide.
20. 20 Implementation Timeline This slide presents a timeline of the key milestones in the rule implementation process for Schedule 4 systems (fewer than 10,000 people).
Note that the first row illustrates a small filtered system that only monitors for E. coli. The second row illustrates a Schedule 4 system that samples for Crypto and decides to conduct all of its monitoring in one calendar year. The third row illustrates a Schedule 4 system that must sample for Crypto and chooses to sample for 2 years. If systems monitor twice per month for either of these contaminants, they are only required to conduct initial source water monitoring for 1 year.
This slide presents a timeline of the key milestones in the rule implementation process for Schedule 4 systems (fewer than 10,000 people).
Note that the first row illustrates a small filtered system that only monitors for E. coli. The second row illustrates a Schedule 4 system that samples for Crypto and decides to conduct all of its monitoring in one calendar year. The third row illustrates a Schedule 4 system that must sample for Crypto and chooses to sample for 2 years. If systems monitor twice per month for either of these contaminants, they are only required to conduct initial source water monitoring for 1 year.
21. 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 Profiling and benchmarking will be covered in-depth at future trainings.
Disinfection profiling and benchmarking was established under the IESWTR and the LT1ESWTR and ensures that PWSs maintain adequate protection against pathogens as they reduce risk from DBPs.
EPA is extending profiling and benchmarking requirements to the LT2ESWTR to accomplish the same objective.
Some PWSs will have to make significant changes in their current disinfection practice to meet TTHM and HAA5 requirements under the Stage 2 DBPR and to provide additional treatment for Crypto under the LT2ESWTR.
To ensure that these PWSs maintain disinfection that is effective against a broad spectrum of microbial pathogens, systems must use disinfection profiling and benchmarking to evaluate the effects of significant changes in disinfection practice on current microbial treatment levels. Profiling and benchmarking will be covered in-depth at future trainings.
Disinfection profiling and benchmarking was established under the IESWTR and the LT1ESWTR and ensures that PWSs maintain adequate protection against pathogens as they reduce risk from DBPs.
EPA is extending profiling and benchmarking requirements to the LT2ESWTR to accomplish the same objective.
Some PWSs will have to make significant changes in their current disinfection practice to meet TTHM and HAA5 requirements under the Stage 2 DBPR and to provide additional treatment for Crypto under the LT2ESWTR.
To ensure that these PWSs maintain disinfection that is effective against a broad spectrum of microbial pathogens, systems must use disinfection profiling and benchmarking to evaluate the effects of significant changes in disinfection practice on current microbial treatment levels.
22. 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. 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. 24 Source Water Sampling Schedules
25. 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. 26 Sampling Before Chemical Treatment & Filter Backwash Recycle This slide illustrates two sample points at a system that recycles its filter backwash water. Sample point 1 is before chemical treatment and before the introduction of the filter backwash recycle. Sample point 2, however, is after the point at which filter backwash water is introduced. Sample point 1 is the sampling location that the system would be permitted to use under the LT2ESWTR.This slide illustrates two sample points at a system that recycles its filter backwash water. Sample point 1 is before chemical treatment and before the introduction of the filter backwash recycle. Sample point 2, however, is after the point at which filter backwash water is introduced. Sample point 1 is the sampling location that the system would be permitted to use under the LT2ESWTR.
27. 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
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.
28. 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 EPAs 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. 29 Reporting Results (cont.) What am I required to report?
30. 30 Questions???? Drinking Water Program
773-3754
Drinking Water Program website:
http://www.state.sd.us/denr/dw
EPA website:
http://www.epa.gov/OGWDW/
