Mich. Admin. Code R. 325.10604f

Current through Vol. 24-05, April 1, 2024
Section R. 325.10604f - Treatment techniques for lead and copper

Rule 604f.

(1) Treatment techniques for lead and copper are as follows:
(a) This rule, R 325.10410, and R 325.10710a to R 325.10710d are the requirements for lead and copper and apply to community and nontransient noncommunity water supplies. These public water supplies are considered "water supplies" or "supplies" in this rule, R 325.10410, and R 325.10710a to R 325.10710d.
(b) These rules establish a treatment technique that includes requirements for corrosion control treatment, source water treatment, lead service line replacement, and public education. These requirements are triggered, in some cases, by lead and copper action levels measured in samples that are collected at consumers' taps.
(c) Through December 31, 2024, the lead action level is exceeded if the ninetieth percentile lead level is more than 0.015 milligrams per liter (mg/l) in tap water samples collected during a monitoring period conducted under R 325.10710a. Beginning January 1, 2025, the lead action level is exceeded if the ninetieth percentile lead level is more than 0.012 mg/l in tap water samples collected during a monitoring period conducted under R 325.10710a. The copper action level is exceeded if the ninetieth percentile copper level is more than 1.3 mg/l in tap water samples collected during a monitoring period conducted under R 325.10710a. The ninetieth percentile lead and copper levels shall be computed as follows:
(i) The highest lead result or the highest copper result from each sampling site taken during a monitoring period shall be placed in ascending order from the sample with the lowest concentration to the sample with the highest concentration. Each sampling result shall be assigned a number, ascending by single integers beginning with the number 1 for the sample with the lowest contaminant level. The number assigned to the sample with the highest contaminant level shall be equal to the total number of samples taken.
(ii) The number of samples taken during the monitoring period shall be multiplied by 0.9.
(iii) The contaminant concentration in the numbered sample yielded by the calculation in paragraph (ii) of this subdivision is the ninetieth percentile contaminant level.
(iv) If a total of 5 samples are collected per monitoring period, the ninetieth percentile is computed by taking the average of the highest and second highest concentrations.
(v) For a water supply that has been allowed by the department to collect fewer than 5 samples under R 325.10710a(3), the sample result with the highest concentration is considered the 90th percentile value.
(d) A supply shall install and operate optimal corrosion control treatment on the system under subrules (2) and (3) of this rule. A supply that is in compliance with the applicable corrosion control treatment requirements specified by the department under subrules (2) and (3) of this rule is in compliance with the treatment requirement.
(e) A supply exceeding the lead or copper action level shall implement all applicable source water treatment requirements specified by the department under subrule (4) of this rule.
(f) A supply exceeding the lead action level after implementation of applicable corrosion control and source water treatment requirements shall complete the lead service line replacement requirements contained in subrule (5) of this rule. All other supplies shall complete the lead service line replacement requirements contained in subrule (6) of this rule.
(g) Under R 325.10410, all water supplies shall provide a consumer notice of lead and copper tap water monitoring results to persons served at the sites (taps) that are tested. A supply exceeding the lead action level shall implement the public education requirements specified in R 325.10410.
(h) Tap water monitoring for lead and copper, monitoring for water quality parameters, source water monitoring for lead and copper, and analyses of the monitoring results under this subrule shall be completed under R 325.10605, R 325.10710a, R 325.10710b, and R 325.10710c.
(i) A supply shall report, to the department, the information required by the treatment provisions of this subrule and R 325.10710d.
(j) A supply shall maintain records under R 325.11506(1)(e).
(k) Failure to comply with the applicable requirements of this rule, R 325.10410, R 325.10710a, R 325.10710b, R 325.10710c, R 325.10605, R 325.10710d, and R 325.11506(1)(e) constitutes a violation of these rules for lead or copper, as applicable.
(l) When notified of a new source or long-term change in treatment as required under R 325.10710d(a)(iii), the department may require the supply to conduct a new or updated corrosion control study as described in R 325.10604f(3)(c), additional monitoring, or other action the department considers appropriate to ensure the supply maintains optimal corrosion control.
(m) The department may require the supply to conduct a new or updated corrosion control study as described in R 325.10604f(3)(c).
(2) Corrosion control treatment steps apply to small, medium size, and large water supplies as follows:
(a) A supply shall complete the applicable corrosion control treatment requirements described in subrule (3) of this rule by the deadlines established in this rule. A large water supply (serving more than 50,000 persons) shall complete the corrosion control treatment steps specified in subdivision (d) of this subrule, unless the supply is considered to have optimized corrosion control under subdivision (b) (ii) or (iii) of this subrule. A small water system (serving 3,300 or fewer persons) and a medium size water system (serving more than 3,300, but fewer than 50,001 persons) shall complete the corrosion control treatment steps specified in subdivision (e) of this subrule unless the supply is considered to have optimized corrosion control under subdivision (b)(i), (ii), or (iii) of this subrule.
(b) A supply is considered to have optimized corrosion control and is not required to complete the applicable corrosion control treatment steps identified in subrule (3) of this rule if the supply is in compliance with 1 of the criteria specified in paragraphs (i) to (iii) of this subdivision. A supply which is considered to have optimized corrosion control under this subdivision and which has treatment in place, or is receiving water from a supply considered optimized under this subdivision, shall continue to operate and maintain optimal corrosion control treatment and meet the requirements that the department determines appropriate to ensure optimal corrosion control treatment is maintained. All of the following provisions apply to being considered to have optimized corrosion control:
(i) A small or medium size water supply is considered to have optimized corrosion control if the supply is in compliance with the lead and copper action levels during each of 2 consecutive 6-month monitoring periods during which monitoring is conducted under R 325.10710a.
(ii) A water supply may be considered by the department to have optimized corrosion control treatment if the supply demonstrates, to the satisfaction of the department, that it has conducted activities equivalent to the corrosion control steps applicable to the system under subrule (3) of this rule. Supplies considered to have optimized corrosion control under this subdivision shall operate in compliance with the department designated optimal water quality control parameters under subrule (3)(g) of this rule and continue to conduct lead and copper tap and water quality parameter sampling under R 325.10710a(4)(c) and R 325.10710b(4), respectively. A supply shall provide the department with all of the following information to support a determination under this subdivision:
(A) The results of all test samples collected for each of the water quality parameters specified in subrule (3)(c)(iii) of this rule.
(B) A report that explains the test methods used by the water supply to evaluate the corrosion control treatments listed in subrule (3) of this rule, the results of all tests conducted, and the basis for the supply's selection of optimal corrosion control treatment.
(C) A report that explains how corrosion control has been installed and how it is being maintained to ensure minimal lead and copper concentrations at consumers' taps.
(D) The results of tap water samples collected under R 325.10710a at least once every 6 months for 1 year after corrosion control has been installed.
(iii) A water supply is considered to have optimized corrosion control if it submits results of tap water monitoring conducted under R 325.10710a and source water monitoring conducted under R 325.10710c that demonstrates, for 2 consecutive 6-month monitoring periods, that the difference between the ninetieth percentile tap water lead level computed under subrule (1)(c) of this rule and the highest source water lead concentration is less than the practical quantitation level for lead. In addition, all of the following provisions apply:
(A) A supply whose highest source water lead level is below the method detection limit is considered to have optimized corrosion control under this paragraph if the supply's ninetieth percentile tap water lead level is less than or equal to the practical quantitation level for lead for 2 consecutive 6-month monitoring periods.
(B) A water supply considered to have optimized corrosion control under this paragraph shall continue monitoring for lead and copper at the tap not less frequently than once every 3 calendar years using the reduced number of sites specified in R 325.10710a(3) and collecting the samples at times and locations specified in R 325.10710a(4)(d)(iv).
(C) A water supply considered to have optimized corrosion control under this subdivision shall notify the department, in writing, under R 325.10710d(a)(iii) of an upcoming long-term change in treatment or addition of a new source as described in that subdivision. The department shall review and approve the addition of a new source or long-term change in water treatment before it is implemented by the water supply. The department may require the supply to conduct additional monitoring or to take other action the department considers appropriate consistent with the requirements of R 325.10604f(2) to ensure that the supply maintains minimal levels of corrosion in the distribution system.
(D) As of July 12, 2001, a supply is not considered to have optimized corrosion control under this subdivision, and shall implement corrosion control treatment under subparagraph (E) of this paragraph unless it meets the copper action level.
(E) A supply that is no longer considered to have optimized corrosion control under this subdivision shall implement corrosion control treatment under the deadlines in subdivision (e) of this subrule. A large water supply shall adhere to the schedule specified in that subdivision for medium size water supplies, with the time periods for completing each step being triggered by the date the supply is no longer considered to have optimized corrosion control under this subdivision.
(c) If a small or medium size water supply exceeds the lead or copper action level and the supply is required to perform the corrosion control treatment steps, the supply may cease completing the treatment steps when the supply is in compliance with both action levels during each of 2 consecutive monitoring periods conducted under R 325.10710a and the supply submits the results to the department. If the supply thereafter exceeds the lead or copper action level during a monitoring period, the supply shall recommence the applicable treatment steps beginning with the first treatment step that was not previously completed in its entirety. The department may require a to repeat treatment steps that were previously completed by the supply if the department determines that this is necessary to properly implement the treatment requirements of this rule. The department shall notify the supply in writing of the determination and explain the basis of the decision. If a small or medium size water supply exceeds the lead or copper action level, the supply, including supplies considered to have optimized corrosion control under subdivision (b) of this subrule, shall implement corrosion control treatment steps under subdivision (e) of this subrule.
(d) Except as provided in subdivision (b)(ii) and (iii) of this subrule, a large water supply shall complete all of the following corrosion control treatment steps by the indicated dates:
(i) Step 1: A supply shall conduct initial monitoring during 2 consecutive 6-month monitoring periods by January 1, 1993.
(ii) Step 2: A supply shall complete corrosion control studies by July 1, 1994.
(iii) Step 3: By January 1, 1997, a shall install optimal corrosion control treatment as designated by the department.
(iv) Step 4: A supply shall complete follow-up sampling by January 1, 1998.
(v) Step 5: A supply shall operate in compliance with the department specified optimal water quality control parameters and continue to conduct tap sampling.
(e) Except as provided in subdivision (b) of this subrule, small and medium size water supplies shall complete all of the following corrosion control treatment steps by the indicated time periods:
(i) Step 1: A supply shall conduct initial tap sampling under R 325.10604f(3)(a) until the supply either exceeds the lead or copper action level or becomes eligible for reduced monitoring. The supply that exceeds the lead or copper action level shall recommend optimal corrosion control treatment within 6 months after the end of the monitoring period during which it exceeds 1 of the action levels.
(ii) Step 2: Within 12 months after the end of the monitoring period during which a supply exceeds the lead or copper action level, the department may require the supply to perform corrosion control studies under subdivision (3)(b) of this rule. If the department does not require the supply to perform the studies, the department shall specify optimal corrosion control treatment under subdivision (3)(d) of this rule within the following timeframes:
(A) For medium-size supplies, within 12 months after the end of the monitoring period during which the supply exceeds the lead or copper action level.
(B) For small supplies, within 12 months after the end of the monitoring period during which the supply exceeds the lead or copper action level.
(iii) Step 3: If the department requires a supply to perform corrosion control studies under subdivision (3)(b) of this rule, the supply shall complete the studies within 12 months after the department requires that the studies be conducted. If the supply has performed corrosion control studies under paragraph (ii) of this subdivision, the department shall designate optimal corrosion control treatment under subdivision (3)(d) of this rule within 6 months after completion of the corrosion control studies.
(iv) Step 4: A supply shall install optimal corrosion control treatment within 12 months after the department designates the treatment.
(v) Step 5: A supply shall complete follow-up sampling under R 325.10710a(4)(b) within 24 months after the department designates optimal corrosion control treatment. The department shall review the supply's installation of treatment and designate optimal water quality control parameters under R 325.10604f(3)(d)(ii) within 6 months after the supply's completion of follow-up sampling.
(vi) Step 6: A supply shall operate in compliance with the department designated optimal water quality control parameters under R 325.10604f(3)(d)(ii) and continue to conduct tap sampling under R 325.10710a(4)(c) and R 325.10710b(6).
(3) A water supply shall complete all the corrosion control treatment requirements described in this subrule that are applicable to the system under subrule (2) of this rule. All of the following apply:
(a) Based on the results of lead and copper tap monitoring and water quality parameter monitoring, small and medium size water systems that exceed the lead or copper action level shall recommend the installation of 1 or more of the corrosion control treatments listed in subdivision (c)(i) of this subrule that the supply believes constitutes optimal corrosion control for that system. The department may require the supply to conduct additional water quality parameter monitoring under R 325.10710b(4) to assist the department in reviewing the supply's recommendation.
(b) When required by the department, a small or medium size water supply that exceeds the lead or copper action level shall perform corrosion control studies under subdivision (c) of this subrule to identify optimal corrosion control treatment for the supply.
(c) Perform corrosion control studies as follows:
(i) A water supply that performs corrosion control studies shall evaluate the effectiveness of each of the following treatments and, if appropriate, combinations of the following treatments to identify the optimal corrosion control treatment for that supply:
(A) Alkalinity and pH adjustment.
(B) Calcium hardness adjustment.
(C) The addition of a phosphate or silicate based corrosion inhibitor at a concentration sufficient to maintain an effective residual concentration in all test tap samples.
(ii) The water supply shall evaluate each of the corrosion control treatments using pipe rig/loop tests, metal coupon tests, partial system tests, or analyses based on documented analogous treatments with other water supplies of similar size, water chemistry, and distribution system configuration.
(iii) A water supply shall measure all of the following water quality parameters in tests conducted under this paragraph before and after evaluating the corrosion control treatments listed in paragraph (i)(A) to (C) of this subdivision:
(A) Lead.
(B) Copper.
(C) pH.
(D) Alkalinity.
(E) Calcium.
(F) Conductivity.
(G) Orthophosphate, when an inhibitor containing a phosphate compound is used.
(H) Silicate, when an inhibitor containing a silicate compound is used.
(I) Water temperature.
(J) Sulfate.
(K) Chloride.
(iv) The water supply shall identify all chemical or physical constraints that limit or prohibit the use of a particular corrosion control treatment and shall document the constraints with 1 or both of the following:
(A) Data and documentation demonstrating that a particular corrosion control treatment has adversely affected other water treatment processes when used by another water supply with comparable water quality characteristics.
(B) Data and documentation demonstrating that the supply has previously attempted to evaluate a particular corrosion control treatment and has found that the treatment is ineffective or adversely affects other water quality treatment processes.
(v) A water supply shall evaluate the effect of the chemicals used for corrosion control treatment in other water quality treatment processes.
(vi) On the basis of an analysis of the data generated during each evaluation, a water supply shall recommend, to the department, in writing, the treatment option that the corrosion control studies indicate constitutes optimal corrosion control treatment for that supply. The water system shall provide a rationale for its recommendation together with all supporting documentation specified in paragraphs (i) to (v) of this subdivision.
(d) Department designation of optimal corrosion control treatment shall be as follows:
(i) Based on consideration of available information, including, where applicable, studies performed under subdivision (c) of this subrule and a supply's recommended treatment alternative, the department will either approve the corrosion control treatment option recommended by the supply or will designate alternative corrosion control treatment from the treatment specified in subdivision (c)(i) of this subrule. When designating optimal treatment, the department shall consider the effects that additional corrosion control treatment will have on water quality parameters and on other water quality treatment processes.
(ii) The department shall notify the supply of its decision on optimal corrosion control treatment in writing and explain the basis for this determination. If the department requests additional information to aid its review, the water supply shall provide the information.
(e) Each supply shall properly install and operate, throughout its distribution system, the optimal corrosion control treatment designated by the department.
(f) The department shall evaluate the results of all lead and copper tap samples and water quality control parameter samples submitted by the water supply and determine whether the supply has properly installed and operated the optimal corrosion control treatment designated by the department in subdivision (d) of this subrule. Upon reviewing the results of tap water and water quality control parameter monitoring by the supply, both before and after the supply installs optimal corrosion control treatment, the department shall designate all of the following:
(i) A minimum value or a range of values for pH measured at each entry point to the distribution system.
(ii) A minimum pH value, measured in all tap samples. Such value shall be equal to or greater than 7.0, unless the department determines that meeting a pH level of 7.0 is not technologically feasible or is not necessary for the supply to optimize corrosion control.
(iii) If a corrosion inhibitor is used, a minimum concentration or a range of concentrations for the inhibitor, measured at each entry point to the distribution system and in all tap samples, that the department determines is necessary to form a passivating film on the interior walls of the pipes of the distribution system.
(iv) If alkalinity is adjusted as part of optimal corrosion control treatment, a minimum concentration or a range of concentrations for alkalinity, measured at each entry point to the distribution system and in all tap samples.
(v) If calcium carbonate stabilization is used as part of corrosion control, a minimum concentration or a range of concentrations for calcium, measured in all tap samples.
(vi) The department may designate values for additional water quality control parameters determined by the department to reflect optimal corrosion control for the supply. The department shall notify the supply in writing of these determinations and explain the basis for its decision.
(g) All supplies optimizing corrosion control shall continue to operate and maintain optimal corrosion control treatment, including maintaining water quality parameters at or above minimum values or within ranges designated by the department, under this subdivision for all samples collected under R 325.10710b(6) to (8). Compliance with the requirements of this subdivision shall be determined every 6 months, as specified under R 325.10710b(6). A water system is out of compliance with the requirements of this subdivision for a 6-month period if it has excursions for a department specified parameter on more than 9 days during the period. An excursion occurs when the daily value for 1 or more of the water quality parameters measured at a sampling location is below the minimum value or outside the range designated by the department. The department may delete results of obvious sampling errors from this calculation. Daily values are calculated as follows:
(i) On days when more than 1 measurement for the water quality parameter is collected at the sampling location, the daily value shall be the average of all results collected during the day regardless of whether they are collected through continuous monitoring, grab sampling, or a combination of both.
(ii) On days when only 1 measurement for the water quality parameter is collected at the sampling location, the daily value shall be the result of that measurement.
(iii) On days when a measurement is not collected for the water quality parameter at the sampling location, the daily value shall be the daily value calculated on the most recent day on which the water quality parameter was measured at the sample site.
(h) The department's determination of the optimal corrosion control treatment specified in subdivision (d) of this subrule or optimal water quality control parameters may be modified by the department. If a request for modification is by a supply or other interested person, the request shall be in writing, shall explain why the modification is appropriate, and shall provide supporting documentation. The department may modify its determination where it concludes that a change is necessary to ensure that the supply continues to optimize corrosion control treatment.
(4) A water supply shall complete the applicable source water monitoring and treatment requirements by the following deadlines:
(a) The deadlines for completing source water treatment steps are as follows:
(i) Step 1: A supply exceeding the lead or copper action level shall complete lead and copper source water monitoring under R 325.10710c(2) and make a treatment recommendation to the department under paragraph (b)(i) of this subdivision not later than 180 days after the end of the monitoring period during which the lead or copper action level was exceeded. The department shall make a determination regarding source water treatment under paragraph (b)(ii) of this subrule within 6 months after submission of monitoring results under this paragraph.
(ii) Step 2: If the department requires installation of source water treatment, the supply shall install the treatment within 24 months after the date of written notification by the department under paragraph (i) of this subdivision.
(iii) Step 3: The supply shall complete follow-up tap water monitoring under R 325.10710a(4)(b) and source water monitoring under R 325.10710c(3) within 36 months after the date of written notification by the department under paragraph (i) of this subdivision. The department shall review the supply's installation and operation of source water treatment and specify maximum permissible source water levels under R 325.10604f(4)(b)(iv) within 6 months after completion of the follow-up tap water monitoring and source water monitoring of this paragraph.
(iv) Step 4: A supply shall operate in compliance with the department specified maximum permissible lead and copper source water levels and shall continue source water monitoring.
(b) Source water treatment requirements are as follows:
(i) A system that exceeds the lead or copper action level shall recommend, in writing, to the department, the installation and operation of 1 of the source water treatments listed in paragraph (ii) of this subdivision. A supply may recommend that no treatment be installed based on a demonstration that source water treatment is not necessary to minimize lead and copper levels at users' taps.
(ii) The department shall complete an evaluation of the results of all source water samples submitted by the supply to determine whether source water treatment is necessary to minimize lead or copper levels in water delivered to users' taps. If the department determines that source water treatment is needed to minimize lead or copper levels in water that is delivered to users' taps, the department will either require installation and operation of the source water treatment recommended by the supply or require the installation and operation of another source water treatment from among the following alternatives:
(A) Ion exchange.
(B) Reverse osmosis.
(C) Lime softening.
(D) Coagulation/filtration.

If the department requests additional information to aid in its review, the water supply shall provide the information by the date specified by the department in its request. The department shall notify the supply in writing of its determination and set forth the basis for its decision.

(iii) Each supply shall properly install and operate the source water treatment designated by the department under paragraph (ii) of this subdivision. The department shall review the source water samples taken by the supply both before and after the supply installs source water treatment and determine whether the supply has properly installed and operated the source water treatment designated by the department.
(iv) Based on the department's review of the source water treatment, the department shall designate the maximum permissible lead and copper concentrations for finished water entering the distribution system. These levels shall reflect the contaminant removal capability of the treatment properly operated and maintained. The department shall notify the supply in writing and explain the basis for its decision. Each water supply shall maintain lead and copper levels below the maximum permissible concentrations designated by the department at each sampling point monitored under R 325.10710c. A supply is out of compliance with this subrule if the level of lead or copper at a sampling point is more than the maximum permissible concentration designated by the department.
(v) Upon its own initiative or in response to a request by a water supply or other interested person, the department may modify its determination of the source water treatment or maximum permissible lead and copper concentrations for finished water entering the distribution system. A request for modification by a supply or other interested person shall be in writing, explain why the modification is appropriate, and provide supporting documentation. The department may modify its determination where it concludes that a change is necessary to ensure that the supply continues to minimize lead and copper concentrations in source water. A revised determination shall be made in writing, set forth the new treatment requirements, explain the basis for the department's decision, and provide an implementation schedule for completing the treatment modifications.
(5) For a water supply that exceeds the lead action level after installing corrosion control or source water treatment, lead service line replacement requirements are as follows:
(a) A water supply that exceeds the lead action level in tap samples taken under R 325.10710a(4)(b) after installing corrosion control or source water treatment, or both, whichever sampling occurs later, shall replace lead service lines under the requirements of this subrule. If a supply is in violation of subrule (2) or (4) of this rule for failure to install source water or corrosion control treatment, then the department may require the supply to commence lead service line replacement after the date that the supply was required to conduct monitoring under R 325.10710a(4)(b).
(b) Annually, a water supply shall replace not less than 7% of the initial number of lead service lines, and galvanized service lines if the service line is or was connected to lead piping, in its distribution system. The initial number of lead service lines is the number of lead lines in place when the replacement program begins. The supply shall identify the initial number of lead service lines in its distribution system, based on a materials evaluation, including the evaluation required under R 325.10710a(1), or the materials inventory required under R 325.11604(c). The first year of lead service line replacement shall begin on the first day following the end of the monitoring period in which the action level was exceeded in subdivision (a) of this subrule. If monitoring is required annually or less frequently, the end of the monitoring period is September 30 of the calendar year in which the sampling occurs. If the department has established an alternate monitoring period, then the end of the monitoring period will be the last day of that period.
(c) If a supply controls the entire service line in accordance with subdivision (g) of this subrule, the supply shall replace the entire lead service line. If the supply does not own the entire lead service line, the supply shall notify the owner of the line, or the owner's authorized agent, that the supply will replace the portion of the service line that it owns and the owner's portion of the line at water supply expense. If the building owner does not consent, the supply shall not replace any portion of the service line, unless in conjunction with emergency repair. Prior to service line replacement, a water supply shall complete both of the following tasks:
(i) Not less than 45 days before commencing replacement of a lead service line, the water system shall provide notice to the resident or residents of all buildings served by the line explaining that they may experience a temporary increase of lead levels in their drinking water, along with guidance on measures consumers can take to minimize their exposure to lead. The water supply may provide notice under the previous sentence less than 45 days before commencing lead service line replacement where the replacement is in conjunction with emergency repairs.
(ii) The water supply shall provide the information required by paragraph (i) of this subdivision to the residents of individual dwellings by mail or by other methods approved by the department. If multifamily dwellings are served by the line, the supply shall have the option to post the information at a conspicuous location.
(iii) In the event of a partial lead service line replacement resulting from an emergency repair, the water supply shall inform the resident or residents served by the line that the supply will, at the supply's expense, collect a sample from each partially replaced lead service line that is representative of the water in the service line for analysis of lead content, as prescribed under R 325.10710a(2)(c), within 72 hours after the completion of the partial replacement of the service line. The supply shall collect the sample and report the results of the analysis to the owner and the resident or residents served by the line within 3 business days of receiving the results. Mailed notices postmarked within 3 business days of receiving the results are satisfactory.
(d) A water supply shall replace lead service lines on a shorter schedule than that required by this subrule, if directed by the department. The department shall take into account the number of lead service lines in the system, where a shorter replacement schedule is feasible. The department shall make this determination in writing and notify the supply of its finding within 6 months after the supply is triggered into lead service line replacement based on monitoring referenced in subdivision (a) of this subrule.
(e) A supply may cease replacing lead service lines under this subrule when samples collected under R 325.10710a(2) meet the lead action level during each of 2 consecutive monitoring periods and the supply submits the results to the department. If the supply thereafter exceeds the lead action level, the supply shall recommence replacing lead service lines under subdivision (b) of this subrule.
(f) To demonstrate compliance with subdivisions (a) to (c) of this subrule, a supply shall report the information specified in R 325.10710d(e) to the department.
(g) A supply is presumed to control the entire service line unless the supply demonstrates in writing that it does not have any of the following forms of control over the entire service line, as provided by state statute, local ordinance, public service contract, or other applicable legal authority:
(i) Authority to set standards for construction, repair, or maintenance of the service line.
(ii) Authority to replace, repair, or maintain the service line.
(iii) Ownership of the service line.
(h) Coating and lining techniques shall not be used to meet the service line replacement requirements under this subrule.
(6) Unless subject to service line replacement requirements under subrule (5) of this rule, water supply service line replacement requirements are as follows:
(a) A water supply shall replace all lead service lines, and galvanized service lines if the service line is or was connected to lead piping. Service lines that are physically disconnected from the distribution system are exempt from this requirement.
(b) Beginning the year after the preliminary distribution system materials inventory is complete, service lines under this subrule shall be replaced at a rate averaging 5% per year, not to exceed 20 years total for replacement of all service lines under this subrule, unless an alternate schedule in an asset management plan is approved by the department. The Water Asset Management Council, if created, may advise the department on such decisions.
(c) If a supply controls the entire service line, the supply shall replace the entire service line at the water supply's expense.
(d) A supply is presumed to control the entire service line unless the supply demonstrates in writing that it does not have any of the following forms of control over the entire service line, as provided by state statute, local ordinance, public service contract, or other applicable legal authority:
(i) Authority to set standards for construction, repair, or maintenance of the service line.
(ii) Authority to replace, repair, or maintain the service line.
(iii) Ownership of the service line.
(e) A water supply shall replace the entire lead service line. If the supply does not own the entire service line, the supply shall notify the owner of the line, or the owners authorized agent, that the supply will replace the portion of the service line that it owns and the owner's portion of the line at the supply's expense. If the building owner does not consent, the supply shall not replace any portion of the service line, unless in conjunction with emergency repair. A water supply shall complete all of the following tasks:
(i) Not less than 45 days before commencing the lead service line replacement, the water supply shall provide notice to the owner and residents of all buildings served by the line explaining that they may experience a temporary increase of lead levels in their drinking water, along with guidance on measures consumers can take to minimize their exposure to lead.
(ii) The water supply may provide notice less than 45 days before commencing lead service line replacement where the replacement is in conjunction with emergency repairs.
(iii) The water supply shall provide the information required by paragraph (i) of this subdivision to the residents of individual dwellings by mail or by other methods approved by the department. If multifamily dwellings are served by the line, the supply shall have the option to post the information at a conspicuous location.
(iv) In the event of a partial lead service line replacement resulting from an emergency repair, the water supply shall inform the resident or residents served by the line that the supply will, at the supply's expense, collect a sample from each partially replaced lead service line that is representative of the water in the service line for analysis of lead content, as prescribed under R 325.10710a(2)(c), within 72 hours after the completion of the partial replacement of the service line. The supply shall collect the sample and report the results of the analysis to the owner and the resident or residents served by the line within 3 business days of receiving the results. Mailed notices postmarked within 3 business days of receiving the results are satisfactory.
(v) Any remaining lead service line, including the privately owned portion, must be documented in the water supply's distribution system materials inventory required under R 325.11604(c).
(f) Service lines that are physically disconnected from the distribution system are exempt from this subrule.
(g) Coating and lining techniques shall not be used to meet the service line replacement requirements under this subrule.

Mich. Admin. Code R. 325.10604f