Another commenter recommended that "sampling period" should be replaced with "collection period" to be consistent with the Safe Drinking Water Information System (SDWIS). Another commenter asked EPA to clarify the difference between "monitoring period" and "sampling period." They also ask EPA to include "lead" in the "trigger level" definition because trigger level is used is in other National Primary Drinking Water Regulations (NPDWRs) such as the Long-term 2 Enhanced Surface Water Treatment Rule.
Commenters asked EPA to add a timeframe to the "pre-stagnation flushing" definition, which could be confused with "flushing" in the 3Ts guidance (USEPA, 2018).
Another commenter asked EPA to reword the "trigger level" definition to be consistent with the "action level" which includes a lead concentration. Another commenter requested that the definition of "trigger level" be clarified with regard to whether if an action level is exceeded, whether trigger level activities should cease. One commenter has a suggested edit for POU device and POE device.
Several commenters asked for the removal of "generally" in the definition of galvanized service line.
Agency Response
Based on public comment, the following definitions have been revised in the final rule to provide more clarity and improve understanding: "action level," "pitcher filter," "first draw sample," "wide-mouth bottle," "find-and-fix," "pre-stagnation flushing," "galvanized service line," "gooseneck, pigtail and connector," "lead service line," "point-of-use device," "school," "elementary school," "secondary school," "tap sampling protocol," "wide-mouth bottle," and changing "trigger level" to "lead trigger level." EPA has created consistency in the use of term throughout the rule where applicable and corrected any errors in definitions, terms and their application to other parts of the LCRR.
Regarding request to include the lead reduction standard in the "pitcher filter" definition, EPA has not included this because the standard may change in the future. The Agency modified the definition to ensure both the pitcher and replacement cartridges are included. While the Agency did not modify the definition to include faucet devices that reduce lead, EPA did revise the risk mitigation measures water systems must take after an LSLR or disturbances to include POU devices. See response to comment Section 6.
In addition, based on comments, EPA has reevaluated "monitoring period," "sampling period," and "compliance period" and has determined that clarity is needed and, thus, has modified the terms and definitions. Further, EPA revised regulatory text to ensure consistent use of the defined terms. EPA has changed these terms to "tap sampling period" for the timeframe when samples must be collected and "tap sampling monitoring period" for the frequency (i.e., semi-annual, annual or triennial). The Agency also clarified that these terms are for monitoring requirements under § 141.86 only.
EPA does not agree that find-and-fix should be referred to differently. The concept of find-and-fix and the terminology was suggested by stakeholders and EPA determined the definition and requirements are clear and understandable. The Agency did, however, clarify that the find-and-fix steps include a site assessment (at the tap sample site with results > 15 ug/L) and treatment assessment (CCT/water quality parameter evaluation). EPA also does not agree that the numerical level in the "find-and-fix" definition should be removed. EPA has retained this for clarity as this initiates the find-and-fix requirements.
EPA has also added several terms and definitions in this final rule based on feedback from commenters, including: "full lead service line replacement," "lead status unknown service line," "system without corrosion control treatment," and "partial lead service line replacement." These have been added to improve communication of replacement events in the rule (§ 141.84) and to better classify service lines if the lead status is unknown. EPA also disagrees with adding a maximum stagnation time to the definition of "pre-stagnation flushing." See response to comment Section 9.
The definition of wide mouth 1-liter bottle has been clarified to specify that it must have an internal mouth diameter of 55 mm.
In response to the comment on the definition of the "trigger level," if a water system has exceeded the trigger level, then subsequently exceeds the action level, the trigger level activities under the rule for that system cease and the action level activities begin.
2.5 Other Existing Definitions Revised in Proposal
Summary of Comments
One commenter suggests that certain phrases included in the "action level" definition be removed. ("lead service line replacement" and "tap sampling"). Commenters suggested EPA revise the definition of "effective corrosion inhibitor residual" instead of including the study requirement in § 141.82. Commenters noted that EPA is using the fifth liter sampling protocol then the "service line sample" definition should be removed from the definitions section. A commenter also requested clarification on "single family structure" due to receiving feedback that "Tier 1 sites" should be residences and not sites used for business. Another commenter requested changes to "find-and-fix," "galvanized service line," "action level" along with several others.
One commenter stated that the "first draw sample" should include a reference to samples taken for schools and child care facilities in accordance with the 3Ts guidance (USEPA, 2018) in addition to the reference to § 141.86.
One commenter expressed concern that the definition of optimal corrosion control has changed from a treatment that minimizes lead to that which reduces it to the trigger level, stating this violates SDWA and lets systems `off the hook' to continuously reduce lead levels and weakens protection of public health in violation of the back-sliding provision. They reference the current definition of OCCT under § 141.2 which states it "minimizes copper and lead concentrations." They express that systems are tasked at all times to continuously reduce lead levels through CCT, and asserted that the proposal removes the responsibility of the system to do this to the "maximum extent feasible." The commenter argues this provides a lower level of protection to public health, stating EPA should remove any provisions that include meeting a lead level to be deemed "optimized" even if it's below the 90[th] percentile trigger level, and failing to do so would be "unlawful."
One commenter asked EPA to specify population size instead of using small, medium, and large systems in the rule, because it is confusing. They state that small systems are defined differently than in other federal safe drinking water regulations, which defines them with a population of 3,300 or fewer. Several commenters asked EPA to retain the current definitions of "small water system" and "medium-size water system" in the final rule. Another commenter states that the definitions for medium and small water systems should indicate if these also apply to non-transient non-community water systems (NTNCWS).
Agency Response
EPA has decided to retain the definitions of small and large water system from the LCRR proposal because to prevent confusion between other NPDWRs. Because of the constraints that water systems serving between 3,301 and 10,000 persons also face, small water systems in the LCRR include those systems that serve 10,000 or fewer persons, and medium-size water system has been updated in this final rule. See response to comment Section 7 for further detail.
In addition, the Agency has amended the following terms to be clearer and avoid misinterpretation: "first-draw sample" and "action level." The final rule prohibits "testing out" of LSLs to count toward LSLR, therefore, as commenters noted, the definition of "service line sample" is no longer applicable. The Agency has removed this definition.
EPA disagrees that a definition for single-family structures is warranted as it is clear it refers to residence and not a nonresidential building.
EPA disagrees with the commenter stating that the numeric value should not be included in the "action level" definition. EPA concluded that it is important that the lead action level and lead trigger level definitions include the 90[th] percentile value that delineates an exceedance which then compels further requirements by water systems to reduce lead levels in drinking water. In agreeance with another commenter, EPA has removed the phrases about LSLR and tap sampling from the action level definition, as these descriptions are more appropriately elsewhere. EPA has not proposed a revision and to the definition of effective corrosion contributor residual and does not believe modification is needed.
EPA maintained the reference to § 141.86 in the definition of first draw sample. Although first draw samples are also collected for child care and school sampling, the protocol uses a different volume and has different stagnation time requirements. Therefore, EPA did not reference § 141.82 in the definition.
EPA did not revise the definition of optimized corrosion control. Adding requirements for a trigger level exceedance did not change the requirement for water systems to continuously reduce lead levels in drinking water. The OCCT definition still means "the treatment that minimizes the lead and copper concentrations at users' taps while insuring that the treatment does not cause the water system to violate any national primary drinking water regulations." The new rule provisions are an improvement to the previous rule requirements for OCCT, because now all water systems must complete corrosion control study if the trigger level is exceeded and implement OCCT if the action level is exceeded (except small systems that elect to implement a small system flexibility option). When a water system meets criteria for optimization (e.g., small or medium-size system that does not exceed the lead trigger level and copper action level for two consecutive six-month monitoring periods under § 141.86) it is "deemed" optimized or re-optimized for the purposes of the LCRR only. However, the water system must still maintain corrosion control continuously, until the State determines in writing that it is no longer necessary.
2.6 Definitions of Child Care Facility and Schools to be Covered Under Testing
Definition of Child Care Facility and Schools
Summary of Comments
Many commenters had concern that the definition included home-based childcares, including those that are unlicensed and those of any size. While others supported the inclusion of these and described how licensing will omit many others that should be required to have testing. In addition, because licensing differs between states and regions, commenters are concerned this will result in a wide variation in applicably of testing in child care facilities.
Several commenters stated that the definition of child care facilities should include those of a certain size, with suggestions of ten or more children. Several commenters are concerned that if home-based child care facilities are included, the water system would not have information on these, they could change frequently and unless there is some routine communication between these facilities and the water systems, then the system cannot identify them. One commenter is concerned if the community water system (CWS) will need to track all child care facilities and the burden associated with this. Several commenters mentioned that if the in-home child care facilities would be included in tap sampling under § 141.86, and therefore should not be included in the definition to avoid duplication of efforts.
Many commenters had concern on the inclusion of "licensed" in the definition of child care facilities. Several explain that this varies widely in states and local jurisdictions so this will create inconsistencies with the rule implementation, especially those that are "registered" not licensed. One commenter asserted that by including only licensed childcares, many facilities are left out. The commenter provided data showing that 24 percent of children in the United States are in unlicensed day cares. One commenter asks EPA to further define licensing in the definition. Another explains that there are several different types of child care facilities in their state, and that in the proposal's definition, by including only licensed facilities, EPA is including only a subset of these. One commenter asks that EPA include "licensed" before "childcare" in all parts of the rule and that this responsibility of testing be transferred to the state's department of human services. Several commenters ask EPA to provide more specificity in the definition and they question which types of facilities are included, such as private facilities.
Many commenters ask that "other location" be deleted from the definition of "school" under § 141.2, as it does not fit with EPA's intent based on cost estimations and could unintentionally include homeschools, nature centers, art and music facilities, athletic sites, museums, etc. These commenters believe the definition to be too broad and explain that it is unclear if private schools are included. One commenter suggests that only those facilities under the state department of education should be included in testing and thus the definition. Many commenters express concern that homeschools are being included in the definition as written and ask for EPA to provide clarification. One such commenter mentions how homeschools are not regulated and the difficulty with finding and tracking these locations, and another describes how the state should be responsible for this list and updating it. Some commenters ask for more clarity in the definition of schools. One commenter asks for clarification if tutoring centers, kindergartens, churches, etc. are included as schools. Another commenter asks that the schools included are only those with state-issued licenses. One commenter supports homeschools to be included in the definition of schools.
Another commenter asked for clarification if community colleges and technical schools are required to be included in school testing under the definition of "school," while another asked to clarify if other facilities like dance academies, churches, park department facilities, etc. are included. One commenter asked EPA to revise the "school" definition to more closely resemble "child care facility." Another commenter explained that schools will be considered private property while service providers manage the PWS. One commenter provided their proposed definition of school which includes a minimum number of students and number of days the facility holds classes or services. It also excludes colleges and universities. Another commenter mentions that private and charter schools may be more difficult to locate and collect samples from.
Agency Response
EPA acknowledges that requiring tap sampling at licensed child care facilities may exclude some unlicensed or in-home child care facilities. However, the Agency determined it is not feasible for water systems to find and track these undocumented child care facilities. Home-based facilities may be included in compliance tap sampling in § 141.86 if they meet site selection tiering criteria. The tap sampling protocol for the school and child care sampling differs from the compliance tap sampling protocol and for facilities located in homes the compliance tap sampling protocol (e.g., 1 liter in volume, first or fifth liter depending on the presence of an LSL) is more appropriate to identify elevated levels of lead. Therefore, EPA has maintained the proposed definition of "child care facility." The final definition of child care facility is "a location that houses a licensed provider of child care, day care or early learning services to children, as determined by the State, local, or tribal licensing agency." EPA believes this provides adequate detail to ensure the majority of child care facilities are captured and is feasible for water systems to comply.
EPA acknowledges commenter concerns and has revised the definition of "school" by removing "or other location" to reduce ambiguity. The Agency did not intend to include sites like museums, nature centers or athletic facilities in the definition and therefore in sampling requirements under § 141.92. Home-based facilities may be included in compliance tap sampling in § 141.86 if they meet site selection tiering criteria. The tap sampling protocol for the school and child care sampling differs from the compliance tap sampling protocol and for facilities located in homes the compliance tap sampling protocol (e.g., 1 liter in volume, first or fifth liter depending on the presence of an LSL) is more appropriate to identify elevated levels of lead.
EPA does not agree that only facilities under the state department of education should be included in testing and therefore excluded this specification from the definition of school, because this may exclude facilities with large student populations. Excluding certain facilities, such a private or any school without a state-issued license could lead to decreased knowledge of lead levels at these facilities and therefore exposure to students. The goal of the LCRR is to protect public health especially those most vulnerable from lead in drinking water. The testing is applicable to elementary and secondary schools and facilities, thereby technical schools, community colleges and universities are not included. To prevent further confusion on school grades to be included in the mandatory testing program in the final rule, EPA has added definitions for "elementary school" and "secondary school" as well. While EPA understands it may be more difficult to locate private or charter schools, since there are fewer in number, the Agency determined it is feasible for water systems to identify these facilities for tap sampling. See response to comment Section 6 for additional information on CWS's requirements to sample for lead in schools and child care facilities.
2.7 Other Needed Definitions
Summary of Comments
One commenter stated the "drinking water outlet" needs clarification regarding schools that no longer use these outlets. Another commenter asked EPA to clarify "metal coupon tests" by including acceptable methods for lead and copper CCT studies, citing references that have cautioned the use of coupon tests. Several commenters ask EPA to define or give guidance on what constitutes a "source change" or "significant treatment change," questioning which changes would fall into these categories.
Another commenter asks EPA to define "secondary students." One commenter urges EPA to update the definition of "optimized corrosion control treatment," because as currently written, it may be placing too much weight on the 90[th] percentile and median concentrations. They state that systems can still have unstable scale when achieving the lowest 90[th] percentile value, and that policy and guidance should be provided to allow for consideration of uncertainties that affect CCT in the field as opposed to in a controlled study.
One commenter suggests including definitions for "full lead service line replacement" and "partial lead service line replacement." Several commenters mention that definitions of "building inlet" and "water main" are not in the rule, and because they are used in the LSL definition they should be explained. One commenter asks for definitions of "orthophosphate measurement," so that systems are all using the same, and "optimization" and "re-optimization." A commenter states that it is important to define "disturbance" as it is used in the preamble. One commenter expresses that the "first-draw sample" definition is not clear with its reference and should be changed to "first liter sample." Another commenter asks that "corrective action" be defined as used in §§ 141.82 and 141.84.
One commenter requested additional detail on what constitutes "localized corrosion control treatment." Several commenters ask EPA to define "pitcher filter tracking and maintenance system" and to include what is required for this in the rule and via guidance. Another commenter asks for the definition of a "notification" for § 141.84 asking if email, voicemail, etc. suffices. Another commenter asks for clarification in the final rule on what defines a "drinking water outlet." "A pipe rig/loop test" is mentioned in § 141.82 in the proposal and a commenter asks EPA to define this.
A commenter asserted that the use of "deemed" in reference to meeting requirements for optimized corrosion control has changed and both SDWIS and the primacy agency do not identify systems as "deemed," thereby a definition is needed. Another commenter states that "lead-bearing plumbing materials" should be modified to "lead-containing plumbing materials" and the "first-draw sample" definition should include the stagnation period.
A commenter recommends the Agency redefine "re-optimization" highlighting its importance for rule requirements such as actions after a trigger level or action level exceedance and include that it must be approved by the state. Another commenter requests that the current definition of "disturbance" as it pertains to LSLs could include maintenance activities, and the definition should preclude these.
One commenter explained that the current definition of OCCT is misapplied by putting too much weight on the 90[th] percentile concentration without considering other factors that can impact CCT. They suggested that there could be systems meeting the lowest 90[th] percentile but still having unstable scales. They ask EPA for the water systems to be given discretion when considering uncertainties and to develop guidance for systems when evaluating factors that could affect the lead levels in drinking water.
Agency Response
In response to commenters, the Agency decided to add the following definitions to the final LCRR: "full lead service line replacement," "partial lead service line replacement," and "lead status unknown service line." It's clear that these definitions are necessary because of new rule provisions under § 141.84 regarding categorization of service lines and LSLRs. EPA has also added the term "system without corrosion control" to ensure consistent implementation of trigger level and action level exceedances for water systems without CCT and for re-optimization requirements for systems with CCT.
As requested by commenters, EPA has included definitions for "localized corrosion control" and "pipe rig/loop test." EPA has also removed "pitcher filter tracking maintenance system" and its associated provisions from the final rule as decisions on tracking systems are best made based on water system capacity. For response to comments regarding source water or treatment changes, see response to comment Section 11.
In response to first-draw sample comments, EPA modifies the definition to specify it is a "one-liter" sample for clarity. As stated, in response to commenters requesting EPA define "secondary students," new definitions of "elementary school" and "secondary school" were added to the final rule. This will clarify these terms in the definition of "school" and which facilities are applicable in § 141.92.
Several areas of the rule have been updated with improved language, such as CCT requirements under §§ 141.81 and 141.82 to address commenters requests for clarification. EPA has established new terms and definitions to categorize the type of service line with regard to its lead status, such as "lead status unknown service line," "galvanized service line," and galvanized requiring replacement under § 141.84 based on commenters recommendations.
For some of the other terms identified in the comments, the Agency added clarifying language in the rule text and preamble. The Agency believes this will resolve the issues described above and improve understanding amongst stakeholders without the need to create new definitions under § 141.2. EPA is working on guidance to address requests from commenters. EPA understands this is a critical component to ensure the rule's effectiveness in protecting public health. The Agency intends to develop implementation guidance targeting the areas of the rule that are most likely to support compliance. In addition to guidance, EPA will also provide training and other supporting materials that will help states and water systems implement the revised rule and promote greater national consistency.
References
National Drinking Water Advisory Council (NDWAC). 2015a. Recommendations to the Administrator for the Long Term Revisions to the Lead and Copper Rule (LCR). December 15, 2015. https://www.epa.gov/sites/production/files/2016-01/documents/ndwacrecommtoadmin121515.pdf.
NDWAC. 2015b. Report of the Lead and Copper Rule Working Group to the National Drinking Water Advisory Council. August 24, 2015. https://www.epa.gov/sites/production/files/2016-01/documents/ndwaclcrwgfinalreportaug2015.pdf.
USEPA. 1998. Consumer Confidence Report Regulation. Federal Register 63(160):44524. August 19, 1998. Washington, D.C.: Government Printing Office.
USEPA. 2000. National Primary Drinking Water Regulations: Public Notification Rule. Federal Register 65(87):25982. May 4, 2000. Washington, D.C.: Government Printing Office.
USEPA. 2006. National Primary Drinking Water Regulations: Long Term 2 Enhanced Surface Water Treatment Rule; Final Rule. Federal Register 71(3): 654. January 5, 2006. Washington, D.C.: Government Printing Office.
USEPA. 2018. 3Ts for Reducing Lead in Drinking Water in Schools and Child Care Facilities: A Training, Testing, and Taking Action Approach (Revised Manual). October 2018. Office of Water. EPA 815-B-18-007. https://www.epa.gov/ground-water-and-drinking-water/3ts-reducing-lead-drinking-water-toolkit.
USEPA. 2019. National Primary Drinking Water Regulations: Proposed Lead and Copper Rule Revisions. Federal Register 84(219):61684. November 13, 2019. Washington, D.C.: Government Printing Office.
USEPA. 2020. National Primary Drinking Water Regulations: Lead and Copper Rule Revisions. Final Rule. Federal Register xx(xxx): p. Date. Washington, D.C.: Government Printing Office.
3 Lead Trigger Level
EPA requested comment on the proposed lead trigger level of 10 ug/L and the actions water systems must take if they exceed this trigger level but not the action level of 15 ug/L, i.e., had a trigger level exceedance (TLE). Specifically, EPA:
       Asked does this level represent an appropriate 90[th] percentile level at which to require systems to initiate progressive actions to reduce drinking water lead levels?
       Requested comment on other 90[th] percentile level thresholds that would be reasonable for water systems to initiate progressive actions to reduce drinking water lead levels.
Most commenters agreed with the incorporation of a trigger level. However, commenters identified a few issues with the proposed trigger level. A significant amount recommended either a lower value (5 ug/L and 1 ug/L were mentioned in some comments), or a health-based value. Commenters also expressed concern that the trigger level would be complex and difficult to implement and interpret.
3.1 General Comments
Summary of Comments
Over a hundred comments addressed general issues associated with the lead trigger level. Most of the commenters either expressed agreement or disagreement with the incorporation of a lead trigger level. Most commenters agreed with the addition of the trigger level. Justifications included: more time for water utilities to determine the cause of the lead exceedances; more time to evaluate corrosion control treatment (CCT); and the prevention of action level exceedances (ALEs). One commenter recommended use of a "bin approach" when dealing with action and trigger levels.
A significant number of commenters recommended lowering the trigger level. Most recommended the level be lower than 10 ug/L as proposed. Several commenters suggested lowering the trigger level to 5 ug/L. One commenter suggested having one benchmark (rather than a trigger level and action level) and setting that at 5 ug/L. One commenter suggested lowering the trigger level to 1 ug/L, mentioning that there is "no safe level of exposure" to lead and that a lower trigger level will let families make "informed decisions about what level of lead contamination they are willing to accept in the water."
Commenters that opposed the trigger level highlighted the complexity of the new rule and that it may be confusing for water systems and customers. One commenter added that the trigger level would result in increased "non-compliance." A commenter asserted that the trigger level actions are excessive and that replacing premise plumbing or addressing poor sampling procedures are sufficient. One commenter warned that the trigger level should be carefully implemented as the new limit may be manipulated to create fear in customers and possibly be "misused by activists." Another commenter mentioned that the trigger level is only good when considering drinking water sources of lead and no other lead sources (i.e., dust, soil). Other commenters suggested eliminating the trigger level and lowering the action level instead.
A few commenters suggested that the trigger level should be a health-based limit. A few commenters asserted that lead levels did not increase over time but may fluctuate over time across sampling locations. They questioned if there was sufficient data to suggest a system with a lead 90[th] percentile of 10 ug/L would exceed the action level of 15 ug/L in future tap sampling, especially if the system does not have lead service lines (LSLs).
A few commenters raised the issue of enforcement. One commenter mentioned that additional trigger level actions must be overseen, reviewed and approved by the state staff. One commenter recommended that if a TLE occurs, the water system should carry out "public education outreach," by sending information to all customers on the issue of lead, and inform customers of ways to mitigate elevated lead. Another commenter suggested that a TLE should first prompt an "assessment" to determine the cause of the elevated lead level as opposed to evaluating CCT. A couple commenters mentioned that a TLE would not prompt sufficient action (i.e., lead service line replacement (LSLR)) to address the elevated lead level thus still leaving families "exposed to lead." Other commenters asked for clarification that the trigger level only applies to lead and not copper and that an alternative term to "trigger level" be used.
Risk communication was another issue raised by commenters. Some commenters expressed concern that the new trigger level would make risk communication more complicated. Other commenters suggested that instead of implementing a trigger level, water systems should focus more on risk communication and continuous optimization of CCT (if the system has CCT). A couple commenters suggested that EPA develop guidance focusing on risk communication.
Agency Response
EPA disagrees with commenters suggesting the elimination of the trigger level. The use of a trigger level of 10 ug/L in the implementation of this treatment technique rule will ensure that systems have a plan in place to rapidly respond if there is an ALE. If the trigger level is exceeded, systems that currently treat for corrosion are required to re-optimize their existing treatment. Systems that do not currently treat for corrosion will be required to conduct a corrosion control study so that the system is prepared to respond quickly if necessary.
EPA disagrees that the trigger level should be eliminated, and the action level should be lowered instead. EPA established the lead action level in 1991 to require small and medium-sized systems exceeding it to install CCT and to require large systems and other systems with optimal corrosion control treatment (OCCT) to conduct LSLR. The action level was based on examination of data at 39 medium sized systems; while it was "limited as a basis for making broad-based estimates of treatment efficacy," EPA concluded that "the data are useful as general indictors of the range of levels systems have achieved with various treatment measures in place." (56 FR 26490; USEPA, 1991). EPA acknowledged in 1991 that the selection of the action level "is not based on a precise statistical analysis of the effectiveness of treatment" but it "reflects EPA's assessment of a level that is generally representative of effective corrosion control treatment, and that is, therefore, useful as a tool for simplifying the implementation of the treatment technique" at those systems. (56 FR 26490). EPA decided to use the same action level as a screen to determine which systems with CCT must also replace LSLs (56 FR 26491). While EPA is not lowering the action level, the Agency is strengthening the public health protections of the treatment technique by improving the sampling procedures to better identify elevated levels of lead. This will result in more systems exceeding the action level and more actions to reduce drinking water exposure to lead.
EPA does not agree that the trigger level should be lowered. The use of a trigger level of 10 ug/L in the implementation of this treatment technique rule provides a reasonable concentration that is below the action level and above the Practical Quantitation Level of 5 ug/L at which to require water systems to take a progressive set of actions to reduce lead levels prior to an ALE and to have a plan in place to rapidly respond if there is an ALE. Requiring such actions of systems only when a trigger level 10 ug/L is exceeded, rather than all systems prioritizes actions at systems with higher lead levels and allows states to work proactively with water systems that are a higher priority. The actions water systems will be required to undertake if their 90[th] percentile exceeds the trigger level will require review and oversight from states to assure that they are effective in reducing drinking water lead levels.
As shown in Exhibits 4-13 and 4-20 of the Economic Analysis for the Final Lead and Copper Rule Revisions," hereafter referred to as the "Final LCRR EA" (USEPA, 2020), setting a lower trigger level would substantially increase the number of water systems required to obtain review and input from their primacy agency to comply with the CCT and LSLR requirements. EPA has concluded it is not practicable for this significant number of water systems to obtain this state review and approval. The number of systems impacted by the trigger level can be estimated by combining the breakout of systems with and without LSLs from Exhibit 4-13 of the Final LCRR EA based on Cornwell et al. (2013) and the percentage of systems projected to exceed the lead trigger level of 10 ug/L but not  the action level of 15 ug/L for the previous rule and final LCRR from Exhibits 4-19 and 4-20 of the Final LCRR EA, respectively. While Exhibit 4-19 shows the percentage of systems between the TL and AL, the baseline LCR does not have a trigger level, so these systems will not be subtracted out from the LCRR to look at incremental impacts.  Under the low and high estimates, 722 and 4,072 CWSs are projected to be impacted by a TLE, respectively. There are also 680 CWS in the low estimate and 2,381 CWSs in the high estimate projected to exceed the lead action level due to the LCRR after subtracting out the ALEs from the existing rule baseline (Exhibit 4-19) to get the increase in ALEs due to the LCRR. The total number of impacted systems above the trigger level that includes systems with a TLE or ALE ranges from 1,402 to 6,453 CWSs. While the system-state interactions are less extensive for TLE, setting the trigger level at 10 ug/L still more than doubles the number of systems impacted under either the low or high estimate scenario for ALEs.
In addition, EPA examined the impacts of a 5 ug/L trigger level using the subset of percent of systems with 90[th] percentiles between 5 and 10 ug/L in Exhibit 4-20 of the Final LCRR EA. Under the low estimate, an additional 2,069 CWSs would be projected to be impacted by the trigger level and under the high estimate, an additional 4,827 CWSs would be projected to be impacted by the trigger level. Combining these CWSs with the ones between 10 and 15 ug/L yields a total of 3,472 CWSs projected to be impacted by a trigger level of 5 ug/L in the low estimate and 11,279 CWS in the high estimate. Even though the system-state interactions are less extensive for TLEs, setting the trigger level at 5 ug/L would represent about a 5-fold increase in the number of systems impacted under either the low or high estimate scenario for ALEs. The high estimate for a 5 ug/L would mean more than 20 percent of CWS would be impacted. Setting an even lower trigger level would have required almost all water systems to obtain review and input from their primacy agencies to comply with the CCT and LSLR requirements. Therefore, EPA has concluded it is not practicable for almost every water system to obtain this state review and approval in the same timeframe.
EPA does not agree that the trigger level should be health-based. The Agency has established a health based maximum contaminant level goal (MCLG) of zero for lead. The trigger level is not a health-based level, rather it is a reasonable level at which to require systems to begin to take a progressive set of actions based upon lead levels at the tap that are appropriate to assure reduced exposure to lead. The concept of including additional thresholds to compel actions before an action level exceedance was suggested by the Association of State Drinking Water Administrators (ASDWA) as a way to focus actions towards the systems with the greatest potential concerns (USEPA, 2018). This regulatory framework is similar to other National Primary Drinking Water Regulations (NPDWRs), such as the Long-Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR), which requires increasing levels of remedial action based on the concentration of the contaminant (USEPA, 2006). EPA has revised the regulatory text in the final rule to improve its clarity and will work with primacy agencies and water systems to assure they understand the different actions that must be taken when systems exceed the lead trigger level or action level.
Commenters raised issues over what the "trigger level" applies to and the use of the term. EPA clarifies that the trigger level only applies to lead, not copper. Also, while EPA appreciates the concern over the terminology, the Agency has decided to maintain use of the term "trigger level" as it initiates an investigatory response as noted in the above paragraph.
EPA agrees with the commenter that raised the concern that the trigger level only addresses lead in drinking water. However, as summarized in the proposed rule federal register notice Section I (USEPA, 2019), EPA highlights the other regulations and efforts that are being carried out to address lead exposure from other sources (i.e. air, soil).
EPA agrees with the commenter suggesting the trigger level should also require water systems to carry out public education outreach. The final rule includes provisions to notify LSL customers when a TLE occurs to provide information about the goal-based LSLR program. For more information on Public Education, refer to response to comment Section 8.
EPA disagrees with commenters that the trigger level results in unnecessary complexity and regulatory burden. EPA determined that a progressive set of actions based upon lead levels at the tap are appropriate to ensure reduced exposure to lead. EPA in its Health Risk Reduction Cost Analysis (HRRCA), as documented in the Final LCRR EA (USEPA, 2020) has found that a significant number of benefits accrue from systems being required to take mitigation activities as a result of TLEs. EPA also examined the costs and found that it is feasible for systems to take the actions required when there is a TLE. It is technically possible for systems to conduct increased tap sampling, take additional steps to improve CCT, and implement a goal-based LSLR program. Requiring these actions when a system's lead levels are high, but not exceeding the action level, will help both systems and states to engage in a manageable and orderly process to reduce lead levels in drinking water so that they remain below the lead action level. Accordingly, inclusion of the trigger level in the final rule will provide for "greater protection of the health of persons" consistent with the statutory authority in Section 1412(b)(9) of the Safe Drinking Water Act (SDWA) for revising existing drinking water standards. Additionally, this proactive approach to lead contamination in response to a trigger level will reduce the likelihood that a water system will exceed the action level in the future or be faced with public health concerns about the need to implement emergency measures such as the distribution of water filters or bottled water in response to a lead crisis.
EPA disagrees with the comments that the trigger level actions are excessive and that replacing premise plumbing or addressing poor sampling procedures are sufficient. Tap sampling is conducted at a small fraction of the number of residences served by a system. Premise plumbing replacement at the sampled house, assuming the system can address it, would only reduce lead for that house. The house next door that is not being sampled may have similar premise plumbing issues that are not being detected. Systems with CCT will re-optimize their existing treatment to try to get below the trigger level.
One commenter stated that lead levels fluctuated at sites, but did not increase over time, and questioned if the system would exceed the action level in future periods, if they don't have LSLs. EPA believes that the trigger level will work well with other changes to the rule to address scenarios like systems that fluctuate above and below the action level. System will no longer be allowed to continue to fluctuate above and below the action level as the LCRR will require them to install CCT or re-optimize existing CCT. Systems without CCT will identify the CCT or small system compliance option that would be implemented if the system exceeds the action level. Fluctuations in lead levels at non-LSL sites may indicate that the existing CCT is not optimized, and the system should re-optimize the CCT to try to get below the trigger level and reduce the variations at sites. For systems without CCT, a TLE will require them to make a recommendation for CCT implemented if there is a subsequent action level exceedance. Sampling pools are not static as new sites enter the sampling pool to replace sites where the customer no longer wants to participate or where an LSL has been replaced. Addition of new sites could affect the 90[th] percentile as well.
EPA would like to clarify for the commenter that assumed that TLEs only trigger planning and do not require any LSLR unless the lead action level is exceeded in the future. The final rule requires water systems to conduct the goal-based full LSLR program at a LSLR rate approved by the state, and if the annual LSLR goal is not reached to conduct public outreach activities, which is an enforceable requirement of the LCRR. For more information on the LSLR requirements, see response to comment Section 6.
EPA acknowledges that risk communication is important and may be challenging for some water systems. However, EPA determined that providing public access to information related to locations of LSLs and tap sampling results will help to educate consumers about the sources of lead in drinking water, the health effects of lead, actions consumers can take and actions the water system is taking to reduce lead in drinking water. EPA received several comments requesting Agency guidance on implementation of the revised rule and in particular on risk communication. EPA understands this is a critical component to ensure the rule's effectiveness in protecting public health. The Agency intends to develop implementation guidance targeting the areas of the rule that are most likely to support compliance. In addition to guidance, EPA will also provide training and other supporting materials that will help states and water systems implement the revised rule and promote greater national consistency.
References
ASDWA. 2018. Comments by the Association of State Drinking Water Administrators (ASDWA) For the Lead and Copper Rule (LCR) Federalism Consultation Docket ID No. EPA-HQ-OW-2018-0007.
Cornwell, D.A, R.A. Brown, and S.H Via. 2016. National Survey of Lead Service Line Occurrence. Journal AWWA. 108(4):E182-E191.
United States Environmental Protection Agency (USEPA). 1991. Drinking Water Regulations; Maximum Contaminant Level Goals and National Primary Drinking Water Regulations for Lead and Copper; Final Rule. Federal Register 56(110): 26460. June 7, 1991. Washington, D.C.: Government Printing Office.
USEPA. 2006. National Primary Drinking Water Regulations: Long Term 2 Enhanced Surface Water Treatment Rule; Final Rule. Federal Register 71(3): 654. January 5, 2006. Washington, D.C.: Government Printing Office. https://www.govinfo.gov/content/pkg/FR-2006-01-05/pdf/06-4.pdf.USEPA. 2019. National Primary Drinking Water Regulations: Proposed Lead and Copper Rule Revisions. Federal Register 84(219):61684. November 13, 2019. Washington, D.C.: Government Printing Office.
USEPA. 2020a. Economic Analysis for the Final Lead and Copper Rule Revisions. Office of Water. December 2020.
4 Corrosion Control Treatment
In the proposed rule, EPA requested comment on the proposed corrosion control treatment (CCT) re-optimization requirements, specifically:
     "EPA requests comment upon the potential actions water systems could take to adjust their corrosion control treatment and how they should work with the State to determine if adjustments to the treatment would better optimize corrosion control."
     EPA received many comments on the proposed requirements, included in § 141.81 (Applicability of Corrosion Control Treatment Steps to Small, Medium, and Large Water Systems) and § 141.82 (Description of Corrosion Control Treatment Requirements). EPA received comments both in support of, and opposition to, the proposed requirements. The Agency received comments on CCT optimization and re-optimization timeframes and steps, corrosion control studies, designation of optimal water quality parameters, corrosion control treatment options, daily optimal water quality parameter calculations and corrosion control treatment review during sanitary surveys.
4.1 General Comments
EPA received general comments on the corrosion control treatment (CCT) optimization and re-optimization requirements proposed in § § 141.81 and 82. EPA also received comments on the deemed criteria proposed in § 141.81(b) for corrosion control optimization or re-optimization. CCT-related comments were also received on the proposed find-and-fix assessment requirement in § 141.82(j) and the small system compliance flexibility options in § 141.93. Finally, EPA received general comments pertaining to the State review of long-term treatment changes or new source additions; consecutive system-related considerations; and other provisions applicable to water systems with optimized and re-optimized corrosion control.
Proposed Corrosion Control Treatment Optimization/Re-Optimization Requirements
Summary of Comments
In the preamble to the proposed rule EPA requested comment on "the overall framework for the proposed LCR revisions," including whether the Agency has "developed proposed revisions that address the variability in conditions among the regulated water systems that affect the levels of lead that may be present in drinking water." In response to these considerations, one commenter believed there would be "a significant number of water systems, particularly community water systems, for which the § 141.81 provisions will not work well," including those with "multiple sources of water supply entering their distribution system, existing corrosion control treatment, more complex source water quality, aged infrastructure also requiring replacement, multiple consecutive water systems with varying distribution system and service line materials, and systems only needing to make minor adjustments to corrosion control treatment."
One commenter expressed general support for the proposed corrosion control treatment requirements and stated that the approach "should help reduce current [environmental justice] disparities." The commenter also suggested that "Because water treatment is consistent across an entire community, stronger requirements that reduce the ability of lead to leach into water from LSLs, leaded solder, and other sources should mitigate, but not eliminate, the disproportionate burden in homes with LSLs."
A second commenter also expressed general support and requested that EPA expand "emphasis on corrosion control programs." The commenter found that the proposal "is likely to be a more economical solution than accelerated and total lead material abatement" and that "a multiple barrier solution through a micro-depositing corrosion control program is also an effective strategy to ensure safety, as has been proven broadly."
Two commenters raised concerns over the variability of conditions from state to state. One commenter asserted that "EPA has disregarded specific concerns for each state" and that "[w]hen using the word `optimal' corrosion control, it restricts a state to force PWSs to implement corrosion control that could have environmentally detrimental impacts and is not the appropriate approach for that state." The second commenter stated, "EPA has assigned several requirements to the States without facilitating the ability to make good decisions for the specific concerns each state may have." The commenter also believed that "use of the wording `optimal' corrosion control restricts any consideration for a state to implement corrosion control that could be more `appropriate' in controlling corrosion" and suggested "chang[ing] the word optimal to adequate to solve this issue."
A commenter believed the proposed revisions "implicitly establish the addition of high-dose orthophosphate addition optimized for minimizing soluble lead release as a `gold standard' for corrosion control treatment," and that the approach "is inappropriate because it (1) limits systems' ability to make timely changes in treatment and sources of supply, (2) limits water systems' ability to respond rapidly to degraded corrosion control performance, and (3) prioritizes performance on a single criterion over all other regulatory and operational considerations."
A commenter raised concerns over the proposed rule because it maintains "the compliance mechanism for corrosion control treatment" that was promulgated under the original Lead and Copper Rule. The commenter believed "water system maintenance of `optimized' water quality parameters does not directly correspond to actual lead levels at consumer taps" and that "such a framework `rewards' water systems for success in maintaining their water quality parameters within `optimal' ranges, even when lead-in-water contamination in their service area is severe." The commenter suggested revising the rule to "replace the LCR's current compliance mechanism for corrosion control treatment with a mechanism that corresponds to lead levels at the tap" and to incorporate "[a] scheme that triggers a violation following a LCR lead action level exceedance." The commenter also suggested EPA "[r]eview all available technologies that would allow water system compliance with non-lead-related national primary drinking water regulations, while also achieving the lowest possible levels of lead at consumer taps." Finally, the commenter requested that, "[s]hould EPA leave [the existing] mechanism in place, it must provide peer-reviewed science showing that: [1] Optimized water quality parameter levels... are reliable predictors of lead-in-water-drinking levels at consumer taps; and [2] Water system maintenance of State-designated "optimal" water quality parameter ranges has prevented large-scale lead-in-water contamination in cities like Washington, DC; Flint, MI; Portland, OR; Newark, NJ; Pittsburgh, PA; and Sebring, OH."
One commenter characterized the proposed corrosion control framework as "marginal improvements to the corrosion control provisions of the LCR." The commenter asserted that "improving corrosion control requirements will only go so far in reducing lead exposure" since it "only serves to limit, not eliminate, exposure to lead." The commenter believed that through a proactive lead service line replacement program, a "constant need to monitor and reoptimize corrosion control would be avoided altogether." Another commenter indicated similar support and rationale for prioritizing the removal of lead service lines over optimization of corrosion control treatment.
A commenter did not support the proposed revisions to the corrosion control treatment requirements based on the belief that it "places the highest emphasis in the water treatment and water quality on protection of lead service lines without regard to the effectiveness of the water system's corrosion control;" "creates a higher cost to provide service to properties with lead service lines;" and "requires all treatment to favor lead service lines which may adversely affect other types of service lines."
With regard to small and medium systems, one commenter believed the proposed rule did not "address legacy issues with current rule related to OCCT," claiming that "[s]mall and medium systems tend to `guess' the right treatment to use with very little data and little to no scientific backing." Another commenter did not believe the "framework for corrosion control will be implemented as presented," claiming that "[s]tates may default to requiring treatment changes because the rule construct creates the impression that action is warranted." The commenter also noted the "proposed rule presents a different administrative structure based on system size," and that "EPA [did] not articulate a basis for the administrative breakpoint in either its benefit-cost analysis or its preamble description of the basis for the rule corrosion control treatment requirements." A third commenter recommended EPA provide justification in the final rule of any "fundamental difference[s] in study or treatment installation requirements for large versus medium-sized systems."
Other commenters broadly suggested states and water systems provide "detailed engineering information about all treatment techniques used by a CWS or NTNCWS to treat their water;" raised concerns over potential public perceptions associated with "prescriptively add[ing] extra chemicals" to drinking water; and suggested a general need for "more research in corrosion control as it relates to all metals, products for use, chemicals, and alternate metal or plastics."
EPA also requested comment on "the complexity of the regulatory requirements that result from targeting different actions for different types of water systems and challenges States and water systems will encounter" and on "ways that the proposed LCR revisions could be simplified and burden, including paperwork burden, could be reduced while still assuring adverse health effects are prevented to the extent feasible." Overall, commenters found the proposed requirements for corrosion control treatment to be complex and suggested EPA simplify the language in the final rule. One of the commenters generally suggested that "EPA more thoughtfully consider the revisions to this rule language, especially with regards to implementation." Several commenters also provided specific suggestions on how § § 141.80, 81 and 82 could be simplified or noted typographical inconsistences in the proposed language.
Commenters also raised general burden concerns over the amount of time it would take system or state staff to understand the proposed requirements and determine system compliance, particularly with regard to § 141.81(a), § 141.81(d) and (e). Another commenter raised a similar concern for "small and medium sized water systems that may not have the personnel or resources to devote to fully understanding the Rule." Commenters also noted terminology and usage as contributing factors to the complexity of the proposed rule. Some did not find a sufficiently clear distinction between `optimization' and `re-optimization.' One of the commenters noted usage of "'optimal' and `optimized' throughout the [proposed rule], sometimes interchangeably" and suggested that "different types of efforts be designated as such: initial CCT or existing CCT, and re-optimized CCT."
Another commenter was concerned the overall optimization/re-optimization proposal introduced the practical quantitation level, as an implicit "treatment objective." The commenter asserted that "[t]he proposed regulatory text draws a connection between the practical quantitation limit and optimized corrosion control;" that "[t]his connection is substantially different than existed under the current LCR, but the Economic Analysis does not take the effect of § 141.81(b)(3) into account;" that "EPA has not attempted to demonstrate whether it is feasible for a sufficient cross-section of water systems in the U.S. to reliably maintain 90th percentile lead levels below the current practical quantitation limit of 5 ug/L so as to consider it `feasible';" and that "[t]he proposed revision also take place [sic] in the context of a proposed rule where primacy agencies have considerable latitude." In light of these concerns, the commenter suggested that "[t]he final rule and associated preamble must be clear that 90th percentile lead levels below the practical quantitation limit is a means of dispensing with additional regulatory burdens not a treatment objective," and that "[w]ater systems of all sizes and descriptions need a clear path forward to compliance and a reliable expectation that if they perform within the parameters of the rule construct they will not be subject to the impulses of regulatory agencies."
Other commenters raised a similar concern with the overall optimization/re-optimization proposal "effectively mak[ing] the trigger level the new standard at which a water system would have to take further action related to corrosion control  -  leaving the action level somewhat less relevant," or otherwise making the trigger level "the de facto action level." The commenters requested that EPA "more fully explain its reasoning for having corrosion control changes contingent upon a trigger level exceedance rather than an action level exceedance."
Commenters also noted the complexity of adjusting corrosion control treatment and the technical expertise required on the part of water systems and states. In light of this, commenters requested the provision of technical training and development of guidance materials to aid water systems and states with the implementation of the proposed corrosion control treatment requirements. Another commenter noted that "[s]imultaneous compliance considerations can be challenging for water systems and States" and requested that "EPA update and maintain the online Decision Tool to Help Utilities Develop Simultaneous Compliance Strategies," which was developed by the Water Research Foundation.
Agency Response
EPA does not agree with the assertion that the provisions in § 141.81 will not work well for community water systems. The Agency recognizes there are many factors to consider when installing or re-optimizing corrosion control treatment (CCT). However, the regulation of lead and copper is complicated by the fact that the presence of these factors and extent to which they may affect CCT effectiveness is unique to each system. Because of their specificity, EPA believes it is not possible to create a national standard that more directly accommodates or addresses each of these factors for the types of systems described in the public comment. Such an approach would result in a regulation that is overly prescriptive and burdensome to implement; the Agency believes a more effective strategy for reducing the presence of lead and copper in drinking water is through strengthening the CCT provisions in § 141.81 and incorporating a trigger level approach that enables systems to address lead and copper corrosion more proactively than under the current rule.
Regarding how the optimal corrosion control treatment (OCCT) provisions intersect with state-specific concerns, EPA notes the goal of the rule is to provide maximum public health protection by reducing lead and copper levels at consumers' taps as close to the MCLGs as is feasible. To accomplish this, EPA established under the 1991 Lead and Copper Rule a treatment technique requirement for systems to install OCCT. Section 1412(b)(7)(A) of the Safe Drinking Water Act (SDWA) requires that such a treatment technique "prevent known or anticipated adverse effects on the health of persons to the extent feasible." For these reasons, the OCCT provisions are not intended to give equal weight to other, non-health-related factors. Doing so would be inconsistent with this statutory provision and could result in systems implementing an OCCT that is less than optimal in its protection of public health. With regard to the terminology suggestion, EPA believes the term `adequate corrosion control' would not  accurately capture these considerations and thus has retained the term `optimal corrosion control' in the final rule.
Regarding the assertion that the proposed CCT requirements will limit a system's ability to make timely changes in source or treatment, or to respond rapidly to degraded corrosion control performance, EPA notes the rule requires consultation with the state regarding such changes because of the potential for unintended consequences that may degrade CCT optimization and put the public at risk. The Agency believes evaluating source and treatment changes  -  in coordination with the state and prior to the system implementing those changes  -  is a critical and necessary component in ensuring the continued protection of public health. Regarding degraded CCT performance, EPA recognizes the need for addressing such issues on a timely basis and has modified provisions in the final rule to address this concern. Systems of any size whose 90th percentiles are between the trigger and action levels may, as specified in final rule § 141.81(d)(1), make state-approved CCT modifications without being required to conduct a CCT study first. Small and medium systems exceeding the lead trigger level or copper action level also may make treatment modifications without being required to conduct a CCT study [§ 141.81(d)(2)(ii)]. For large systems and systems of any size with lead service lines (LSLs) exceeding the lead action level, the Agency believes a CCT study is necessary to ensure continued protection of public health after implementing any necessary CCT changes. In these cases, the final rule does not allow systems to make CCT modifications without first evaluating its impacts through a study. Finally, EPA disagrees with the assertion that the rule prioritizes a performance on single criterion over all other regulatory and operational considerations. Under proposed and final rule § 141.82(c)(1)(i), systems without CCT are required to evaluate the effectiveness of alkalinity and pH adjustment, orthophosphate- or silicate-based corrosion inhibitors, and if appropriate, combinations of the treatments to identify the OCCT for the system. Systems are not required to install orthophosphate-based treatment where such evaluations identify another CCT option (e.g., alkalinity and pH adjustment) as the OCCT. This evaluation process also accounts for the regulatory and operational considerations that were raised as a concern. Under § 141.81(c)(1)(iv), systems must identify chemical or physical constraints limiting or prohibiting the use of a particular CCT. Systems also must evaluate the effect that CCT may have on other drinking water quality treatment processes [§ 141.81(c)(1)(v)]. Systems with CCT also must conduct these activities as specified in § 141.82(c)(2).
 Regarding the suggestion for a regulatory scheme that uses action levels as a basis for triggering a compliance violation, EPA notes such a scheme would implicitly establish maximum contaminant levels (MCLs) for lead and copper. As discussed in the preamble to the 1991 Lead and Copper Rule [56 FR 26476], the regulation of lead and copper is complicated by the fact that a major contributor to tap lead levels is the corrosion of lead-bearing materials that are present within consumers' private premises. Since these are not owned or controlled by a public water system (PWS), EPA determined the statutory definition of "public water system," as defined in section 1401(4) of the Safe Drinking Water Act (SDWA), precludes the Agency from promulgating a drinking water regulation that holds a PWS liable for conditions that are beyond their control. This interpretation also is consistent with the plain language of the statute and with the reasonable approach of requiring systems to address only those problems over which they exercise sufficient control for remedial action. See comment response section 19.2.
Peer-reviewed science relating to the use of WQPs within the LCR framework are documented extensively in the preamble to the 1991 Lead and Copper Rule [50 FR 26466].
Regarding the cited cases of large-scale, lead-in-drinking-water contamination, EPA notes that nearly all resulted from long-term treatment changes that were implemented by consecutive systems without fully evaluating its corrosion control implications or determining the new OWQPs that would be necessary for the system to maintain an optimized CCT. The Agency also notes that, to address consecutive system-related concerns associated with large-scale treatment changes, EPA finalized the change to § 141.82(g) on continued operation and maintenance of optimal corrosion control treatment (OCCT) to apply to consecutive systems receiving water supplied by another system.
EPA disagrees with assertions that improving the corrosion control requirements will only go so far in reducing exposures to lead in drinking water, or that corrosion control treatment constitutes a lesser priority than LSL removal. The Agency notes that even where systems prioritize the removal of all LSLs, it will not sufficiently allow for the discontinuation of CCT because of the presence of other lead sources that will remain in the plumbing of consumers' homes and other buildings. These sources could include interior household pipes; lead solders and fluxes used to connect copper pipes; and alloys containing lead, including some faucets made of brass or bronze. In light of the persistence of these other, non-LSL sources of lead, the use of optimized CCT and related monitoring will continue to be necessary. The Agency thus considers the CCT requirements to be a critical and meaningful component of the rule's framework for reducing public exposure to lead, even for water systems who either do not have LSLs or have successfully removed of all LSLs from the distribution system.
EPA does not agree with the broad claim that the CCT requirements place an emphasis on LSLs over  other sources of lead in drinking water. Under the proposed rule, water systems must install or operate optimal corrosion control treatment, which is defined in § 141.2 as the treatment that "minimizes the lead and copper concentrations at users' taps while insuring that the treatment does not cause the water system to violate any national primary drinking water regulations." The CCT provisions in § § 141.81 and 82 direct systems to install optimized or re-optimized treatment meeting this definition. The specifics of how individual systems shall tailor their CCT to meet this definition is left to the individual discretion of that system and its state. EPA has retained this approach in the final rule. The Agency also believes the assertions about the proposal `favoring' LSLs over other considerations  -  e.g., higher cost to properties with LSLs or adverse impacts on other types of service lines  -  do not account for the extent to which LSLs can be a prevalent source of lead contamination. Numerous studies have evaluated the contribution of lead in drinking water from different sources (e.g., service lines, faucets, meters). A study published by American Water Works Association (AWWA) Water Research Foundation (2008) "Contributions of Service Line and Plumbing Fixtures to Lead and Copper Rule Compliance Issues" (Sandvig et al., 2008) estimates that 50 percent to 75 percent of lead in drinking water comes from LSLs. Given that systems are required to install  optimized corrosion control treatment that minimizes lead and copper concentrations at users' taps and the extent to which LSLs are a significant source of lead, EPA does not believe it would be in the interest of public health for the rule to allow systems to ignore LSL sources since it may result in the installation of a less-than-optimal CCT.
The claim that small and medium systems `guess' the right OCCT using little data or scientific backing appears to assume the rule leaves OCCT designation to the sole discretion of the system. However, the provisions in §§ 141.81 and 141.82 of the existing rule specify that OCCT must be designated by the state. Per § 141.82(d), this designation must be based on the state's consideration of available information, any CCT studies conducted by the system, and the system's OCCT recommendation. Section 141.82(d) also requires systems to provide additional information where it is requested by the state to aid its review, thus providing a mechanism for ensuring that OCCT designations are based on data that is scientifically sound. EPA has retained these existing provisions in the final rule and update them to reflect designation steps and corresponding rule citations for optimized vs. re-optimized OCCT.
Regarding state implementation of the corrosion control treatment framework, the Agency believes action is warranted when a system triggers the CCT re-optimization requirements. EPA has revised provisions in § 141.81(d) to clarify that such an action may include modifications to the existing CCT rather than an outright CCT change. Systems have the opportunity to evaluate whether re-optimization can be achieved through modification of the existing CCT when making its re-optimization treatment recommendation to the state in accordance with § 141.82(a). Upon its review of the recommendation, the state may approve the modification when designating re-optimized OCCT as specified in § 141.82(d)(2) unless the state believes a CCT change is necessary for the system to achieve re-optimization.
With regard to the structure of the CCT requirements, their relation to system size, and whether there are any fundamental differences, EPA notes the matter has been discussed extensively in the preamble to the original rule [56 FR 26492]. Summarizing briefly, the rule does not establish different treatment requirements based on system size; all sizes are uniformly required to optimize CCT. EPA's approach simply establishes a presumption, supported by available data, that certain systems  -  e.g., small and medium systems  -  have optimized CCT if they meet certain levels. Large systems must make a more detailed technical showing of meeting the optimized CCT requirement by leveraging their greater technical sophistication and operational expertise. EPA proposed 10 ug/L trigger level as a reasonable concentration that is below the action level and above the PQL of 5 ug/L at which to require water systems to take a progressive set of actions to reduce lead levels prior to an action level exceedance, and to have a plan in place to rapidly respond if there is an action level exceedance. Requiring these actions when a system's lead levels are high, but not exceeding the action level, will help both systems and states to engage in a manageable and orderly process to reduce lead levels in drinking water so that they remain below the lead action level. Accordingly, inclusion of the trigger level in the final rule will provide for "greater protection of the health of persons" consistent with the statutory authority in Section 1412(b)(9) of the Safe Drinking Water Act (SDWA) for revising existing drinking water standards. Additionally, this proactive approach to lead contamination in response to a trigger level exceedance will allow systems to quickly take action if there is a ALE, while reducing the likelihood that a water system will exceed the action level in the future. Also see trigger level response to comment in Section 3.
Regarding costs and benefits, EPA's Health Risk Reduction Cost Analysis found that a significant number of benefits accrue from systems being required to take mitigation activities as a result of trigger level exceedances. In examining the costs, EPA also found that it is feasible for systems to take the actions required when there is a trigger level exceedance. Small community water systems and non-transient non-community water systems have the added flexibility to select a non-CCT option  -  LSL replacement, installation and maintenance of point-of-use devices, or replacement of lead-bearing plumbing materials  -  where the system finds such a flexibility option to be the most feasible, affordable, and effective compliance alternative compared to CCT.
EPA recognizes some consumers may have specific concerns about the chemicals that are used to mitigate the potential for lead exposures in their drinking water. EPA notes that the corrosion control treatment options remaining in the final rule have been shown to be effective at minimizing lead and copper levels at taps and provide a high level of public health protection in public water supplies. EPA notes that the corrosion control treatment option recommended by a public water system must be approved by the state.
EPA recognizes the general burden concerns raised and has made a number of modifications in the final rule that address many of the general concerns raised by commenters about the burden to systems and states, complexity and effectiveness of the proposed CCT provisions, as well as its successful implementation. EPA has reorganized optimization and re-optimization study requirements based on `bins' the Agency has identified. These `bins' are based on system characteristics such as CCT status,  the presence of LSLs and lead 90th percentile value. See the response in section 4.5.1 for a detailed discussion of each optimization/re-optimization `bin' and its applicable study requirements. EPA also has added a definition of "systems without corrosion control treatment" in the final rule to clarify the instances under which systems would use the optimization or re-optimization pathway. Language throughout § 141.81, particularly § § 141.81(a), (d) and (e), has also been revised to make the specific requirements easier to follow. The Agency believes these modifications will address concerns by simplifying rule requirements and terminology, making it easier for states and systems of all sizes to determine compliance, offer greater clarity on which systems would proceed along a given pathway and more clearly identifying the distinctions between trigger and action level exceedances. The added clarity from these changes also address concerns related to how optimization-related terminology are distinct, particularly as it pertains to installation vs. re-optimization of CCT.
EPA recognizes the concerns raised over the implementation of the practical quantitation level (PQL) as an implicit treatment objective and has revised § 141.81(a) for greater clarity and consistency on the intended path forward to compliance. Large systems without CCT are explicitly required under § 141.81(a)(1)(ii) to complete the treatment installation steps in § 141.81(e) if they exceed the lead PQL. EPA had initially proposed the lead trigger level; however, the Agency believes requiring such action when the lead PQL is exceeded allows states to work proactively with these systems that are a higher priority by virtue of the larger populations they serve and the lack of existing CCT. EPA also has modified § 141.81(a)(1)(iii) to clarify under what circumstances large systems with CCT that exceed the lead PQL, but do not exceed the lead trigger level or the copper action level, may be required by the state to complete the CCT re-optimization steps in § 141.81(d). Because of the general magnitude of the population served by large water systems, EPA believes it is important for states to have the flexibility under § 141.81(a)(1)(iii) to require system re-optimization where it determines further lead reductions are achievable by these systems. EPA concludes these modifications will make the rule more protective of public health while also addressing the concern with states potentially implementing the rule in a manner that uses sub-PQL concentrations as a basis for triggering the optimization/re-optimization requirements.
EPA disagrees with the characterization that the trigger level would effectively be a new standard that makes the action level less relevant, or that it would otherwise be a de facto action level. As discussed above, EPA proposed the trigger level as a reasonable concentration that is below the action level and above the PQL at which to require water systems to take a progressive set of actions to reduce lead levels prior to an action level exceedance, and to have a plan in place to rapidly respond if there is an action level exceedance. See response to comment Section 3.
Finally, EPA received several comments requesting Agency guidance on implementation of the revised rule. EPA understands this is a critical component to ensure the rule's effectiveness in protecting public health. The Agency intends to develop implementation guidance targeting the areas of the rule that are most likely to support compliance. In addition to guidance, EPA will also provide training and other supporting materials to help states and water systems implement the revised rule and promote greater national consistency. Additionally, the Water Research Foundation Tool described was developed jointly and maintained by WRF on its website. However, WRF no longer supports that tool.
References
Sandvig, A., P. Kwan, P.E., G. Kirmeyer, P.E., Dr. B. Maynard, Dr. D. Mast, Dr. R. R. Trussell, P.E., Dr. S. Trussell, P.E., A. Cantor, P.E., MCSD, and A. Prescott. 2008. Contribution of Service Line and Plumbing Fixtures to Lead and Copper Rule Compliance Issues. Denver, Colo.: Awwa Research Foundation. Peer reviewed by AwwaRF Project Advisory Committee.
Deemed Criteria for Corrosion Control Optimization or Re-Optimization
Summary of Comments
EPA received several comments specifically related to the proposed provisions in § 141.81(b), which specifies the criteria under which systems are deemed to have optimized or re-optimized corrosion control.
One commenter stated that "implementation for [§ 141.81](b)] provisions are very complex, and the proposed revisions further complicate the concept of what it means to be deemed," and that "the trigger level adds unnecessary complexity in the revisions to § 141.81(b)(1) and the new (b)(2)." The commenter disagreed that "a PWS can be `re-optimized' and deemed using (b)(3);" and suggested EPA "remove the provision for any size PWS to be considered optimized under (b)(3), or at minimum, require (b)(3) systems to be re-evaluated for the optimization criteria with each round of compliance monitoring." The same commenter also suggested EPA "abandon the `deem' compliance mechanism. Instead, EPA and primacy agencies should simply track which systems have CCT installed or small system flexibilities implemented, and which systems do not." The commenter provided specific implementation suggestions related to the review of systems with a `deemed' milestone status and to subsequent state reporting of system milestones. Finally, the commenter requested "clear guidance from US EPA as to if and when a primacy agency should change the designation (deem) status of a PWS that installs OCCT."
Commenters also sought clarification on several specific aspects related to § 141.81(b). One commenter sought clarity on whether systems previously deemed to have optimized corrosion control treatment that later exceed the lead trigger level, but not the lead action level, would still be considered optimized while undergoing re-optimization steps. One commenter found § 141.81(b)](2)(i) to be "unclear when a State could not require a water system to meet optimal water quality parameters" and provided specific language suggestions. This commenter also raised a more general question on how, under the proposed rule, "a large system [is] deemed optimized if it does not meet (b)(3) of this section."
Another commenter believed the proposed requirements established a "new, unspoken trigger" where large systems "may be required to evaluate for and install corrosion control treatment" if their 90th percentile exceeds 5 μg/L. Two other commenters raised a similar observation and suggested that EPA clarify "under what circumstances large, non (b)(3) water systems without [trigger level exceedances] or copper [action level exceedances] are not optimized and are therefore candidates for re-optimization" and that states require "each of these systems to complete corrosion control treatment steps" in § § 141.81(d) or (e). They also suggested EPA clarify in § 141.81(b)(3) that small and medium water systems, with a corrosion control treatment that has not been designated as optimal by the state, may be required to perform corrosion control treatment studies under § 141.82. One of the commenters also suggested revising the proposed rule to state that "systems with CCT, even when treatment has not been designated cannot turn off the treatment process without state approval."
Two commenters sought to understand the specific circumstances in § 141.81(b)(3)(iii) that qualify as a `new source.' One suggested EPA "[s]pecify by rule (or in guidance, at a minimum) what constitutes a change in source or treatment;" the other requested EPA revise § 141.81(b)(3)(iii) so that it would "not trigger a re-optimization of corrosion control." Commenters also requested general clarification on § 141.81 (b)(3)(iv); whether § 141.81 (b)(3)(iv) should include a reference to the lead action level; and whether the term `date' in § 141.81(b)(3)(v) "refers to the date the sampling was conducted or the date that the results of the sampling are finalized." For the latter, the commenter suggested specifying in the final rule "that the exceedance begins at the end of the sample period once all samples have been collected, properly entered into the compliance calculation, and the state has determined and notified the system an exceedance occurred in the preceding monitoring period."
Finally, commenters provided suggested language for the final rule and noted typographical inconsistences within the proposed language of § 141.81(b).
Agency Response
EPA has revised § 141.81(b) to provide more clarity on which systems can be deemed optimized and how these systems can continue to be deemed optimized under this section. Language also was added to clarify the circumstances under which systems deemed optimized or re-optimized under § 141.81(b) must continue to demonstrate that they qualify in all subsequent rounds of monitoring. EPA has also clarified that where the state has set optimal water quality parameters, small and medium systems that meet the action level but exceed the trigger level cannot be deemed optimized under § 141.81(b)(2). EPA also notes that, as part of the streamlining process, § 141.81(b)(3) was extensively revised to provide greater clarity with subparts (i), (iii),(iv) and (v) deleted and replaced with "RESERVED" in the final rule. Large non-(b)(3) systems are optimized by meeting the optimal water quality parameters specified by the state for optimal corrosion control treatment.
EPA disagrees with the suggestion to abandon the deemed optimized provisions in § 141.81(b). The Agency concludes these provisions continue to serve the purpose of prioritizing optimization actions at systems with higher lead levels and allows states to work proactively with water systems that are a higher priority by virtue of these elevated levels. Removing the provision would substantially increase the number of water systems required to obtain state review. EPA has concluded it is not practicable for such a significant number of water systems to obtain these reviews/approvals from their states. Additionally, such an approach would be overly prescriptive for systems with lower lead 90ths since they may not be able to achieve further reductions. In such cases, the suggested requirements would not provide meaningful opportunities to protect public health. EPA has thus retained the provision in the final rule for administrative ease.
EPA acknowledges the concerns raised over the implementation of the practical quantitation level (PQL) as an implicit trigger. EPA has revised provisions in § 141.81(a) that the Agency believes simultaneously addresses the expressed concerns about the deemed optimized provisions in § 141.81(b). Large systems without corrosion control treatment (CCT) are explicitly required under § 141.81(a)(1)(ii) to complete the treatment installation steps in § 141.81(e) if they exceed the lead PQL. EPA believes requiring such action when the lead PQL is exceeded allows states to work proactively with these systems that are a higher priority by virtue of the larger populations they serve and the lack of existing CCT. EPA also has modified § 141.81(a)(1)(iii) to clarify under what circumstances large systems with CCT that exceed the lead PQL, but do not exceed lead trigger level or the copper action level, may be required by the state to complete the CCT re-optimization steps in § 141.81(d). Because of the general magnitude of the population served by large water systems, EPA believes it is important for states to have the flexibility under § 141.81(a)(1)(iii) to require system re-optimization where it determines further lead reductions are achievable by these systems. EPA has also included revisions in § 141.81(a) that address the concerns related to systems of any size with a non-state-designated CCT. These revisions direct a system without corrosion control treatment to complete the applicable CCT steps prescribed in § 141.81 (d) or (e). EPA also has included a definition in the final rule for the term "system without corrosion control treatment" that specifically identifies these non-state-designated-CCT-systems as fitting the definition of the term.
Corrosion Control Treatment-Related Comments on Proposed Requirement for Find-and-Fix Assessments at Tap Sample Sites Exceeding the Lead Action Level
Summary of Comments
EPA received several CCT-related comments on the proposed requirement for a find-and-fix assessment in accordance with § 141.82(j). (See response to comment section 13 for summaries and responses to other, non-CCT related comments on the proposed find-and-fix provision.) The assessment steps proposed in § 141.82(j) would be triggered "when a tap sample site exceeds the lead action level under monitoring conducted under § 141.86." As stated in the preamble to the proposed rule, "the water system would be required to determine if problems with the CCT are leading to elevated levels of lead in the tap samples and then implement a mitigation strategy if necessary." In addition, the preamble noted that "CCT adjustment may not be necessary to address every exceedance."
One commenter found the proposal to be protective, but stated that "[t]he provision that creates a CCT study is unwarranted and inappropriate for instances when a single compliance sample is >15 ug/L."
Numerous other commenters did not support the proposal, raising concerns over a single, elevated tap sample result potentially triggering the need for a corrosion control study or a system-wide CCT re-evaluation. One of the commenters urged "clarify[ing] the rule to better show that a new corrosion control study is not warranted based on one localized set of sample results." Another stated, "elevated lead levels at individual homes point to the need to investigate local issues such as water use patterns or building plumbing, or localized water quality issues. These isolated instances may do not inform [sic] the effectiveness of CCT, and reevaluation and adjustment of system-wide CCT based on localized issues may lead to adverse impacts on other water quality parameters." A third commenter suggested that "[i]f a distribution system... has documentation that it contains no LSLs, then any trigger level or action level exceedances at a home should be treated as an isolated event and the system should be exempt from corrosion control requirements." A final commenter, similarly echoing concerns about the potential for CCT optimization to be triggered by a single find-and-fix result, stated their position that the proposal "sets rigid timelines for compliance and does not sufficiently allow public water systems to investigate and evaluate both current available CCT measures or future options."
EPA received several requests for clarification on CCT-related aspects of the find-and-fix provisions proposed under § 141.82(j). One commenter requested general clarification on "how systems that have already exceeded an AL or TL are impacted by `find and fix', when they are already in the process of installing, optimizing, or re-optimizing treatment." Another commenter requested clarification on whether proposed § 141.82(j)(1) was intended to apply to all systems or "only systems with optimal corrosion control treatment installed." Another commenter raised concerns over the proposed requirement in § 141.82(j)(3) for water systems to "determine if either localized or centralized adjustment of the optimal corrosion control treatment (initial, modified, or re-optimized) is necessary and submit the recommendation to the State." The commenter sought "greater clarity on what EPA means when it refers to `localize corrosion control treatment.'" The commenter also recommended "that the proposed rule should focus on evaluations of possible system wide corrosion control adjustments," noting that "[w]hile in theory a water system could potentially add small chemical feed stations in various locations throughout its distribution system to supplement phosphate levels in certain neighborhoods, in practice this would be extremely challenging to plan, implement, operate, and maintain." One of the commenters also noted a specific provision of proposed § 141.82(j)(5)  -  "[s]ystems without corrosion control treatment required to install optimal corrosion control treatment shall follow the schedule in § 141.81(e)"  -  and raised the following questions: "Is the EPA suggesting one sample site over 15 ug/L could trigger a water system into the corrosion control steps? If this is the case, why are corrosion control treatment requirements based on the lead and copper 90th percentile of tap samples?"
Agency Response
Many commenters interpreted the proposed rule to require CCT modifications as the typical response to address a site that exceeded a lead concentration of 15 μg/L. EPA has modified final rule § 141.81(j)(3) to further clarify that CCT modification may not be necessary to address every exceedance, and that other distribution system actions may include flushing to reduce water age. . For those instances where the find-and-fix corrosion control assessment monitoring finds that optimal water quality parameters are not being maintained in a portion of the distribution system, systems may need to implement localized or centralized adjustment of corrosion control treatment. A system that does not have existing corrosion control treatment is not required to conduct a corrosion control study or to install treatment as a result of find-and-fix unless the state determines it is necessary. See section 13 for responses to non-CCT-related considerations on find-and-fix requirements.
Corrosion Control Treatment-Related Comments Pertaining to Systems Using the Small System Compliance Flexibility Options Under § 141.93
Summary of Comments
EPA received several comments on corrosion control-related matters that relate to the small system compliance flexibility provisions proposed in § 141.81(f). The proposed revisions prescribe the specific steps and deadlines applicable to small community water systems (CWSs) and non-transient non-community water systems (NTNCWSs) using the small system compliance flexibility options under § 141.93. (Note: For a complete discussion of non-CCT-related comments, see the corresponding section on comments pertaining to the small system flexibility provisions proposed in § 141.93.)
As proposed in § 141.80(d)(3),"[a]ny small water system that complies with the applicable small system compliance flexibility requirements specified by the State under § 141.81 and § 141.93 shall be deemed in compliance with the treatment requirement in paragraph (d)(1) of [§ 141.80]." One commenter sought clarification on how an action level exceedance would affect system compliance with the treatment requirement and whether it would trigger a continuation of the corrosion control steps.
One commenter generally suggested "integrat[ing] these [small system flexibility] options into § 141.81 as methods of CCT." One commenter suggested revising the rule to include "language emphasizing that small systems with CCT already in place cannot stop treatment without prior approval from their primacy agency."
Under § 141.81(f)(3), EPA proposed the specific requirements and time periods for each of the compliance flexibility options. One commenter recommended revising the paragraph to more clearly delineate which of the provisions would be applicable to small CWSs vs. NTNCWSs.
Agency Response
EPA has revised 141.81(a)(3) to clarify that the CCT steps in § 141.81 (d) or (e) apply when the system has selected CCT as the small system option under § 141.93. EPA has also added a requirement that systems with CCT that select a different small system compliance flexibility option must maintain their existing CCT until the state determines it is no longer necessary. Systems that select one of the other compliance flexibility options follow the schedule in § 141.81(f).
The rule requires that systems implement the compliance flexibility option after the first action level exceedance. EPA disagrees with comments that suggested including the small system flexibilities in the regulatory text of § 141.81. The Agency deemed it appropriate to keep small system compliance flexibility requirements together in § 141.93 because they are intended as equivalent options in lieu of CCT.
Under the final rule, all of the compliance flexibility options are available to small and non-transient, non-community water systems as discussed in the responses to comments on § 141.93. As such the schedule in § 141.81 (f)(3) will apply to either type of system using that compliance option.
Corrosion Control Treatment-Related Comments Pertaining to State Review of Long-Term Treatment Changes or New Source Additions
Summary of Comments
As stated in the preamble to the proposed rule, EPA proposed requiring that "all water systems that change their source water or make significant treatment changes obtain approval from their primacy agency prior to making the change." Under the proposed provisions, "any water system deemed to have optimized or re-optimized corrosion control" under § 141.81(b)(3)(iii), or "any water system subject to a reduced monitoring frequency under [§ 141.86(d)(4)]," would be required to notify the State in writing "of any upcoming long-term change in treatment or addition of a new source." EPA expects states will review the proposal and "evaluat[e] and mitigat[e] the impacts of the source water change or treatment change on corrosion control."
Two commenters agreed with the above proposal and for states to approve all source and treatment changes. The commenters further suggested that "the proposed rule should specifically state that systems with CCT, even treatment that has not been designated, cannot turn off the treatment process without State approval" and that final rule "must strictly prohibit changes to water source or water chemistry without a comprehensive and scientiﬁcally robust study of the impact of these changes on lead-in-water levels at the tap and the corrosion control treatment in place (if any)."
Three commenters suggested requiring a CCT study prior to implementing any source water or treatment change. The commenters believed that such an approach would assist water systems in "identify[ing] simultaneous compliance and corrosion control issues prior to any such changes" and prevent unintended impacts that would result in elevated lead and copper levels system-wide. One of the commenters also provided suggested language for EPA consideration.
Commenters also raised concerns over how the review of source water and treatment changes would be implemented by water systems and states, and expressed their position that "[t]here is not enough detailed information in the proposed rule or guidance to help water systems and primacy agencies to understand the potential corrosion impacts of design changes and the required activities for various design projects." Another commenter stated a similar position, that "[w]hile US EPA is proposing that all PWSs notify their primacy agency prior to making a source or treatment change, the onus will remain on the states to determine the impact of potential changes and any required actions for the PWS." The commenter suggested EPA "include more detailed and specific information in the rule or guidance" and noted that their state program has "developed guidance to determine what constitutes a significant change to source or treatment." The commenter provided a detailed list of potential considerations that could be included in the suggested rule or guidance. Briefly, the list identified considerations relating to the level of review that would be required by the state; the need for corrosion control treatment installation or re-optimization, formal treatment studies, and additional water quality parameter monitoring; and impacts to consecutive systems.
With specific regard to treatment changes, one commenter suggested that the final rule "should differentiate between significant treatment changes and minor treatment changes requiring OCCT re-evaluation." The commenter considered alum- to ferric-based coagulant changes to be significant. The commenter considered minor treatment changes to be "powder activated carbon and potassium permanganate addition" and changes in "orthophosphate percent purity or an ortho-polyphosphate blend percentage." Another commenter similarly suggested clarifying, in the final rule or guidance, "what constitutes a change in source or treatment" and whether "a new well installed near an existing well, at the same depth, in the same aquifer, [is] considered a new source." The commenter also suggested providing additional clarity with regard to "[w]hat actions are expected of the customer supply if the seller makes changes to their source or treatment? A third commenter suggested that "[t]he proposed rules or guidance to the State should specifically allow demonstration of no change in treated water quality when implementing a long-term change." As an example, the commenter indicated they had implemented a long-term treatment change to address zebra mussel concerns in the system's raw water infrastructure and were able to demonstrate that no changes in treated water quality had occurred. A fourth commenter noted their state drinking water program "require[s] construction permits for changes in treatment" and certified professional engineers "to complete the design for the improvements/substantive changes" and concluded that this approach had "proven to be helpful should there be large changes."
Agency Response
EPA understands there may be instances where an upcoming long-term change in treatment or addition of a new source may merit CCT re-evaluation to safeguard against potential deterioration in water quality or unintended consequences. EPA also acknowledges commenters' concerns with water systems potentially modifying their existing treatment practices without first informing the State or conducting supporting evaluations or studies demonstrating the need for such a change. In the final rule, the general corrosion control requirements in § § 141.80(d)(4) specify that water systems must notify, and receive approval from, the State pursuant to § 141.90(a)(3) of any upcoming long-term change in treatment or addition of a new source. The State may require additional monitoring or other actions the State deems appropriate to ensure the water system maintains minimal levels of corrosion in its distribution system. The final rule includes an additional monitoring requirement in § 141.86(d)(2)(iv) further specifying that systems adding a new source or making a long-term treatment change shall monitor every six months at the standard number of sites listed under § 141.86(c) until the system meets the lead and copper action levels for two consecutive six-month monitoring periods, unless the State determines that the addition of the new source or long-term change in treatment is not significant and, therefore, does not warrant more frequent monitoring. Systems that do not exceed the lead and copper action levels, and/or the lead trigger level for two consecutive six-month monitoring periods may reduce monitoring in accordance with paragraph § 141.86(d)(4) of this section. If a new source or treatment change is deemed significant by the State, the water system may be required to take appropriate steps such as increased lead, copper, and water quality parameter (WQP) monitoring or the re-evaluation of CCT given the potentially different water quality conditions of the source or treatment change.
Commenters generally supported state review of long-term treatment changes or new source additions; some were concerned with systems shutting off treatment processes where CCT was in place but had not been designated as OCCT. EPA notes that under § 142.10(a)(4) states are required to maintain a program to ensure the design and construction of new or substantially modified public water system facilities will be capable of complying with State primary drinking water regulations. One state commenter noted that its permit review process was helpful in identifying large changes. Several commenters suggested requiring a CCT study for any treatment or source changes. EPA agrees the CCT studies have significant value in evaluating the impacts of potential changes. However, there may be existing sources of information such as previous CCT studies, source water quality, other treatment evaluations or state or system experience that allow for the evaluation of impacts without initiating a new CCT study. That information would be part of the state's review.
Many commenters were concerned with the requirements for state evaluation of treatment or new source additions without some criteria that identify what constitutes such a change or addition. Several commenters offered what considerations would identify a treatment changes or what types of treatment changes would be considered minor. Given the complexity of corrosion chemistry, the wide variability in source water quality and distribution systems materials and EPA's and State's experiences in LCR compliance problems with systems making source or treatment changes or adding new sources, EPA does not believe it is feasible to establish such national criteria that can be used to evaluate treatment or source changes or new source additions.
Finally, with regard to the requirement that systems on reduced tap monitoring must notify the state of any long-term changes in treatment or addition of a new source, EPA notes the provision was added in the 2007 short-term revisions to the Lead and Copper Rule. The examples on long-term treatment changes in § 141.90(a)(3) have been retained in the Revised Lead and Copper Rule. The state must review and approve a change before it is implemented by the system. EPA believes that guidance is the best pathway to provide additional information on long-term treatment changes and addition of new sources. See response to comment section 4.1.1 for further discussion of implementation guidance.
Consecutive System Considerations
Summary of Comments
EPA received comments relating to proposed § 141.82(g). The provisions proposed would require water systems to ensure continued operation and monitoring for optimal corrosion control treatment and re-optimized corrosion control treatment. In § 141.82(g)(1), EPA also proposed these provisions would "apply to all systems, including consecutive systems that distribute water that has been treated to control corrosion by another system." One commenter requested that EPA clarify "the information that will be required from the consecutive system in order to ensure it is in compliance" and "the implications for a wholesale system if the consecutive system does not maintain compliance." The commenter also stated that "[f]or consecutive systems, it is unclear if the wholesale water system is responsible for any exceedances in the consecutive system" and suggested that "[a]ny exceedances, monitoring requirements, and outreach should be the responsibility of the consecutive system and failure to perform any action required by this regulation by a consecutive system should not impact the compliance standing of the wholesale system." A second commenter did not agree with inclusion of this provision but did not provide any additional information or supporting rationale. If maintained in the final rule, the commenter suggested that the provision "be outlined much more clearly, as it is easily missed as currently proposed."
EPA also received comments that suggested revising the proposed corrosion control treatment (CCT) requirements to include further consideration of consecutive water systems. Commenters claimed there to be variability in how states and local regulatory authorities address compliance concerns for these systems and that the revised rule would significantly impact how consecutive systems would comply moving forward, particularly with regard to the optimization/re-optimization and find-and-fix assessment requirements. Commenters also suggested clarifying what would be the regulatory expectations for both the consecutive system as well as the wholesaler and how a trigger level exceedance would factor into those expectations.
One commenter suggested providing clarity on what would be required of consecutive water systems without CCT that exceed the trigger or action level; what impacts it would have on the supplying system; and how exceedances would be addressed "for a consecutive system that receives water from two or more supplying systems." Another commenter suggested adding clarity on "[w]hat actions are expected of the customer supply if the seller makes changes to their source or treatment" and "[w]hat actions are expected of the seller if a customer exceeds a trigger or action level."
Another commenter suggested "clarifying in the rule the expectation for consecutive systems that purchase all of their water from systems that have optimized corrosion control in place" and that "water parameters should not differ significantly from the primary system." A third commenter sought clarity on whether a trigger level exceedance would be "aggregated" among its "member communities" or whether "a single exceedance of either the trigger level or find-and-fix sample" would trigger the proposed rule's optimization requirements. A fourth commenter suggested clarifying "who is the responsible party (wholesale or consecutive system) for the consecutive PWS to achieve compliance of § 141.82(g) to operate and maintain optimal corrosion control treatment (OCCT), including maintaining water quality parameters at or above minimum values or within ranges designated by the State, when the consecutive PWS has no control over the operation and maintenance of the CCT." A fifth commenter suggested clarifying requirements pertaining to "[c]orrosion control designation and re-optimization for consecutive systems." A sixth commenter requested clarification for "when consecutive system monitoring requirements should apply." In light of the interconnected nature of water systems in the commenter's state, the commenter questioned whether the rule would pose a requirement "to have consecutive systems install corrosion control treatment when they do not already have facilities" and claimed that such an approach would be costly for consecutive systems. The commenter recommended EPA clarify the requirements for "consecutive systems that do not have currently constructed treatment facilities and clarify any options that may be available including those requiring cooperation with the wholesale provider."
Finally, one of the commenters recommended that "the rule or guidance be clear that treatment decisions for wholesale or regional systems will continue to be made based on regional data, not the results from a single consecutive system."
Agency Response
EPA recognizes the need for addressing how the optimization and re-optimization requirements intersect with consecutive systems. EPA notes both the proposed and final rules specifically calls out consecutive systems as being subject to the § 141.82(g) requirement for continued operation and monitoring for optimal CCT and re-optimized CCT. The Safe Drinking Water Act (SDWA) requires compliance with all National Primary Drinking Water Regulations (NPDWRs) by all public water systems subject to coverage under the Act. The exceptions to coverage under Section 1411 of the SDWA would not apply to the typical consecutive water system. A consecutive public water system subject to coverage under SDWA is fully responsible for meeting all requirements of the NPDWRs. Therefore, a consecutive system  -  and not its wholesaler, unless they are treated as a single system under a modified monitoring requirement set forth by the State and concurred by EPA (discussed below)  -  would be required to take action to address a trigger/action level exceedance or failure to comply with the continued operation and monitoring for OCCT and re-optimized OCCT requirements under § 141.82(g). Any source water additions or treatment changes on the part of a wholesaler that may impact a consecutive system's ability to maintain optimized or re-optimized CCT would similarly require a consecutive system to take action to ensure it remains in compliance with all rule requirements.
Alternatively, under 40 CFR 141.29, EPA allows states to "modify the monitoring requirements under Part 141 to the extent that the interconnection of the system justifies treating them as a single system for monitoring purposes." However, any monitoring must be conducted pursuant to a schedule specified by the State and concurred by EPA. In that case, any compliance determinations would be based on the data collected under the modified monitoring requirements set forth in the State-approved schedule with which EPA must concur. For the purpose of compliance with the LCRR, these modified monitoring requirements would need to ensure that monitoring locations for both tap samples and distribution water quality parameter samples are representative of taps sampled at sites served by a LSL and water quality parameters throughout the combined distribution system. These representative samples would be used to determine the need for the combined system to optimize/re-optimization treatment, where the lead 90th exceeds a trigger or action level, as well as to determine the combined system's compliance with the provisions of § 141.82(g).
Other Provisions Applicable to Water Systems with Optimized and Re-Optimized Corrosion Control
Summary of Comments
EPA received several comments on other proposed requirements applicable to water systems with optimized or re-optimized corrosion control. First, with regard to designation of optimal corrosion control treatment (OCCT) and optimal water quality parameters, commenters noted language throughout § § 141.81 and 82 of the proposal that reflected state "designation" of OCCT, re-optimized corrosion control treatment, and optimal water quality control parameters (OWQP). The commenters stated that under a typical state process, a water system would submit a proposed recommendation or design and the state would approve it as the OCCT or OWQP. For consistency, commenters suggested revising the language in the final rule to reflect "the State will review and approve."
A second set of provisions for which EPA received comment relates to § 141.82(h), under which the state may modify treatment decisions for optimal corrosion control and re-optimized corrosion control. A commenter requested that EPA clarify the following portion of proposed § 141.82(h): "The State may modify its determination... to ensure that the water system continues to optimize corrosion control treatment re-optimized corrosion control treatment."
EPA received comment on the proposed § 141.82(i), under which EPA "may review optimal corrosion control treatment determinations made by a State." Two commenters supported maintaining this provision in the final rule. One also requested that "more CCT training with appropriate levels of corrosion control lessons to improve staff's technical knowledge on this complex subject, as well as, more funding to hire additional staff."
Agency Response
Regarding terminology relating to designation of OCCT and optimal water quality parameters, EPA disagrees with the suggestion to change the regulatory text relating to a State "designation" of OCCT, re-optimized corrosion control treatment, and optimal water quality control parameters (OWQPs) because the processes for determining the treatment and OWQPs does not consist only of review and approval of the system's recommendations. The State must designate either the system's recommended treatment, or another treatment from a list of treatments provided in the regulations. The State also must determine and subsequently designate the appropriate OWQPs. Therefore a "designation" or specification by the State more accurately describes the process required by the regulations. In addition, the Agency has made the determination to maintain the existing terminology and provisions to avoid confusion and for administrative ease.
EPA has revised § 141.82(h) to address the typographical error pointed out by the requested clarification on this provision.
With regard to the requested Agency implementation guidance relating to § 141.82(i), see the response to comment section 4.1.1.
4.2 Timeframes for CCT Optimization and Re-Optimization
Summary of Comments
EPA requested comment on the proposed corrosion control treatment re-optimization requirements and received several comments on the matter as it relates to the proposed timeframes associated with the re-optimization steps in § 141.81(d). Many of the comments are also applicable to the timeframes associated with the proposed optimal corrosion control treatment installation steps in § 141.81(e).
Under § § 141.81(d)(3) and (e)(3), EPA proposed that water systems would be required to complete corrosion control treatment studies within 18 months. One commenter generally noted that the timeframe required for conducting corrosion control studies would depend on the type of study performed by the water system. According to the commenter, timing could range from three months, for a lead solubility study, to as long as one to two years for a pipe loop/rig study. Other commenters generally stated that they did not believe the proposed timeframe of 18 months for completion of corrosion control studies would be sufficient; that the proposal "sets rigid timelines for compliance and does not sufficiently allow public water systems to investigate and evaluate both current available CCT measures or future options;" and that the timing would be "impossible to meet under most public budgeting and procurement processes."  A third commenter claimed that "[p]lanning for, budgeting, designing and conducting the corrosion control study for CCT re-optimization can be time-consuming and costly, it could take up to three years to plan for and complete the corrosion control study" and suggested revising the rule to provide for "a phased approach to establishing deadlines for CCT re-optimization" that "will give the CWSs an opportunity to conduct an in-depth study and take any corrective actions as needed." A fourth commenter suggested EPA evaluate the timeframes associated with CCT studies and treatment recommendations, "to see if the amount of time can be shortened when possible." Commenters also suggested EPA "ensure that the final rule is structured so that water systems are able to make timely decisions on corrosion control treatment that is appropriate for their specific situation as shown by the information available" and allow a "re-optimization timeline of up to three years." To ensure that the final rule is structured so that water systems are able to make timely decisions on corrosion control treatment that is appropriate for their specific situation as shown by the information available" and allow a "re-optimization timeline of up to three years."
With regard to pipe loop/rig studies, one commenter asserted that "the time required to do a harvested pipe flow through study is not compatible with the proposal requirement that the study be completed and reported to the Primacy Agency in 18 months" and suggested that "[a] more realistic time frame is 30 months." The commenter also stated, "EPA's most recent corrosion control guidance notes that pipe loops can require years of operation to provide useful data" and observed that "[a]s a specific example, in 2017 [EPA] Region 5 issued a letter to Flint noting that pipe loops must be run for a minimum of a year to provide appropriate data on each test condition." The commenter estimated "a best-case scenario of 17 months and a more realistic time frame of 2 + years," based on scientific literature and field experience, and provided a breakout of the timing required for performing each phase of such a study. The commenter estimated at least 3 months would be required for planning, design, and construction of a pipe loop/rig; 3 to 9 months would be required for pipe loop/rig stabilization; 2 months would be required for transition periods to/from different corrosion control treatments; 6 to 12 months would be required for stabilization periods to/from different corrosion control treatments; and 3 months would be required for final data analysis and report development.
A second commenter similarly concluded that "18 months is insufficient" and recommended that "providing states greater flexibility to adjust the 18-month time period if good cause is shown that additional time is needed to complete a corrosion control treatment study, perhaps with a maximum time limit of 45 months." Based on first-hand experience in performing a pipe loop/rig study, the commenter stated requiring 50 months, of which the "pipe rig study itself consumed about 42 months." The commenter noted the following factors that they believe "influenced the need for more than 18 months to complete the pipe rig study:" multiple water sources, LSL harvesting, and pipe loop/rig conditioning. Since the commenter's water system utilized multiple water sources, it was necessary to harvest LSLs for more than one pipe loop/rig and subsequently operate these rigs for the corrosion control study. The commenter stated, "[t]o harvest 32 usable LSLs, [water system] crews excavated over 100 service lines. Many of these service lines proved to be unsuitable for the study because they had been previously repaired, were insufficient in length or were damaged during excavation." Once the pipe loop/rig had been constructed, the commenter noted that "it took approximately eight months to adequately condition the lines." Finally, the commenter stated that "due to regulatory timing under the current rule, [the commenter] began testing the different corrosion control treatments before the lines were adequately conditioned, and as a result experienced challenges, including mechanical issues, which required a temporary cessation of operation, affecting the data collected."
A third commenter stated that pipe loop/rig stabilization can "last for several months before the evaluation of the various conditions can even begin." According to the commenter, "the time required to set up, allow the scales to become stable from both the physical disturbance and then the changing test conditions could easily exceed the total 18 months allowed in the proposed rule for performing pipe loop experiments." Instead, the commenter recommended that the proposal allow systems to "develop a timeline with the state and engage the state more often during any study. In that case the system can provide the data to the state in the event that the pipe loops may take longer than expected to reach a baseline or there is a problem performing the study."
A fourth commenter estimated the necessary timeframe for completing corrosion control studies utilizing pipe loops/rigs is "easily likely to exceed the 18 months mandated in the proposal." The commenter indicated that "[b]udgeting for, selecting, and hiring an engineering firm to assist a water system in evaluating its treatment can take months to over a year;" that "[i]f use of a pipe loop test rig is appropriate for that evaluation, assembling it and acclimating the harvested lead pipe until it is stable enough for statistically useful results can take 6 to 12 months;" and that "[t]esting alternatives may require evaluation of performance over different seasonal water quality conditions."
A commenter suggested that corrosion control studies utilizing pipe loops/rigs "should include water testing for a minimum of 1 full year to evaluate seasonal effects" and "should account for at least 3 years in their time to comply with any study requiring a pipe loop." According to the commenter, "study design and construction will require 6 months minimum, but often longer for construction if space and lead service lines are not readily available." The commenter also noted that LSL excavation "cannot be done during freezing temperature months or rain" and that "[p]ipe loop scales need to acclimate for after at least 1 year of routine operation to provide meaningful results."
A commenter believed that "[p]ipe loop/rigs require significant technical, managerial, and financial capacity which makes them difficult for systems to execute within the proposed rule deadlines." The commenter also shared anecdotal observations related to the performance of these studies by a large system: "lead service line pipe loops took 2.5 years to set up due to substantial challenges with harvesting lead service lines. Then, after the pipe loops were constructed, conditioning, testing, data analysis and report preparation took an additional 2 years."
Other commenters stated their general belief that an 18-month timeframe would be insufficient for performing a corrosion control study that utilized a pipe loop/rig and indicated the time needed to harvest LSLs, stabilize pipe loop/rig conditions, and generate data representative of seasonal water quality fluctuations as general constraints.
EPA proposed requiring water systems to install re-optimized corrosion control treatment, or complete the necessary treatment modifications to achieve re-optimized corrosion control, within 12 months in accordance with proposed § 141.81(d)(5). Water systems installing optimal corrosion control treatment in accordance with proposed § 141.81(e)(5) would be required to do so within 24 months. One commenter generally suggested that EPA revise the proposed rule to "allow primacy states to designate a shorter time frame."
One commenter stated that, "in some instances, it may be possible to take steps more quickly using available information and less time-consuming analyses." However, the commenter believed that "complex cases or situations where significant capital construction" would require more than 12 months to procure funding, contract for design and construction services, and complete construction. The commenter also asserted that the "expectations, oversight, financing, and logistics associated with significant capital improvements to drinking water treatment facilities are such that the [Safe Drinking Water Act] provides a three  -  five-year window for treatment changes." The commenter did not believe "all changes that occur following an evaluation of corrosion control practice will require such an extended timeline," but suggested the rule should not "be constructed in a manner that requires water systems and states to seek variances in order to accomplish required improvements."
Other commenters similarly believed that the proposed timeframe of 12 months would be insufficient. One commenter claimed it would be insufficient "to implement any agreed upon changes to corrosion control treatment;" that "[o]nce the final treatment is agreed upon, significant time is needed to design, permit, and build the appropriate facility;" and that "[m]any systems also have complex situations such as several sources of water entering a system, consecutive system considerations, public communications, and wastewater treatment issues that must be addressed prior to a change in the water chemistry." Another commenter generally stated that the timeline for treatment implementation is "impossible to meet under most public budgeting and procurement processes."