Tap Water Monitoring for Lead and Copper

Section 611 TITLE 35: ENVIRONMENTAL PROTECTION SUBTITLE F: PUBLIC WATER SUPPLIES CHAPTER I: POLLUTION CONTROL BOARD PART 611 PRIMARY DRINKING WATER STANDARDS SECTION 611.356 TAP WATER MONITORING FOR LEAD AND COPPER Section 611.356  Tap Water Monitoring for Lead and Copper All suppliers must sample for lead and copper at taps used to provide water for human consumption in compliance with the requirements of this section. a)         Sampling site location 1)         By the start of the first tap monitoring period in which sampling for lead and copper is required under subsections (c) and (d), each supplier must identify potential tap sampling sites and submit a site sample plan to the Agency as required in Section 611.360(a)(1)(A).  The Agency may require modifications to submitted site sample plans.  Each supplier must identify a pool of tap sampling sites that will allow the supplier to collect the number of lead and copper tap samples required in subsections (c)(1) and (d)(1). A)        To select sampling sites, a supplier must use information regarding the material of service lines and connectors, including lead, copper, and galvanized iron or steel, required to be collected under Section 611.354. B)        Suppliers must identify locations in the site sample plan by selecting from sites in the highest tier, unless the site has been found to be unavailable, in compliance with subsection (a)(4). C)        Sampling sites cannot include sites with installed point-of-entry (POE) treatment devices or taps with point-of-use devices designed to remove inorganic contaminants, except in supplier's water systems using these devices at all service connections for primary drinking water taps to meet other primary and secondary drinking water standards under Section 611.363(c)(1). 2)         A supplier that has fewer than five sites with drinking water taps that can be used for human consumption meeting the sample site criteria of this subsection (a) to reach the required number of sample sites listed in subsections (c)(1) and (d)(1), must collect at least one sample from each tap and collect additional samples from those taps on different days during the tap sampling period to meet the required number of sites.  Alternatively, the Agency may allow these suppliers to collect a number of samples fewer than the number of sites specified in subsections (c)(1) and (d)(1), provided that 100 percent of all taps that can be used for human consumption are sampled.  The Agency must approve this reduction of the minimum number of samples in writing based on a request from the supplier or onsite verification by the Agency. 3)         A supplier serving sites with premise plumbing made of lead and/or that are served by a lead service line must collect all samples for monitoring under this section from sites with premise plumbing made of lead and/or served by a lead service line.  A supplier that cannot identify enough sampling sites with premise plumbing made of lead and/or served by lead service lines to meet the minimum number of sites required in subsections (c)(1) and (d)(1) must still collect samples from every available site, in compliance with subsection (a)(4), containing premise plumbing made of lead and/or served by a lead service line and collect the remaining samples in compliance with the tiering requirements under subsection (a)(4). 4)         Sampling sites must be selected from the highest tier available (Tier 1 is the highest tier and Tier 5 is the lowest tier).  Sites are available unless a customer refuses to participate in sampling, or a supplier has made at least two outreach attempts at a site and has not received a response.  The number of customer refusals and non-responses for compliance sampling during each tap sampling period must be submitted to the Agency in compliance with the requirements at 611.360(a)(2)(H).  Suppliers may continue conducting outreach at sites considered unavailable and may subsequently add such sites to the site sample plan for any reason, such as receiving a service initiation request from a new property owner or occupant or receiving a new consumer request for sampling.  A supplier without a large enough number of sites from a higher tier to meet the number of sites required in subsections (c)(1) and (d)(1) may sample sites from the next highest tier. For suppliers where Tier 2 sites comprise at least 20 percent of the residential structures served by the CWS supplier, Tier 2 sites may be sampled even when Tier 1 sites are available. A)        Tier 1 sampling sites are single-family structures with premise plumbing made of lead and/or served by a lead service line. B)        Tier 2 sampling sites are buildings, including multiple-family residences, with premise plumbing made of lead and/or served by a lead service line. C)        Tier 3 sampling sites are sites that are served by a lead connector.  Tier 3 sites are also sites served by a galvanized service line or containing galvanized premise plumbing identified as ever having been downstream of a lead service line.  Tier 3 for CWSs only includes single-family structures. D)        Tier 4 sampling sites are sites that contain copper premise plumbing with lead solder installed before the effective date of the Agency's applicable lead ban.  Tier 4 for CWSs only includes single-family structures. E)        Tier 5 sampling sites are sites that are representative of sites throughout the supplier's distribution system.  For purpose of this subsection (a), a representative site is a site in which the plumbing materials used at that site would be commonly found at other sites served by the supplier. b)         Sample-collection protocol. 1)         Except for samples the supplier collects under subsections (b)(1)(C) and (D), all tap samples collected for analysis of lead and copper must be one liter in volume and have stood motionless in the plumbing system and/or service line of each sampling site for at least six hours.  Bottles used to collect samples for analysis must be wide-mouth, one-liter sample bottles, as defined in Section 611.350 (b).  Samples from residential housing must be collected from an interior kitchen or bathroom sink cold-water tap.  Samples from a nonresidential building must be collected at an interior cold-water tap from which water is typically drawn for human consumption.  Samples may be collected by the supplier, or the supplier may allow members of the public to collect samples after providing instructions for collecting samples in compliance with this subsection (b)(1).  Sample collection instructions cannot direct the sample collector to remove or clean the aerator or flush taps prior to the start of the minimum six-hour stagnation period.  To protect members of the public from injury due to handling nitric acid, samples may be acidified up to 14 days after the sample is collected.  After acidification to resolubilize the metals, the sample must stand in the original container for a period of time, as specified by the approved EPA method in § 40 C.F.R. 141.23 selected for sample analysis.  If a supplier allows members of the public to sample, the supplier cannot challenge the accuracy of the sampling results based on alleged sample collection errors. A)        The first-liter sample must be analyzed for lead and copper at sample sites where both contaminants are required to be monitored.  At sample sites where only lead is required to be monitored, the first-liter sample may be analyzed for only lead. B)        For sites served by a lead service line, which fall under Tier 1 and Tier 2, an additional fifth-liter sample must be collected at the same time as the first-liter sample and must be analyzed for lead.  To collect a first-liter-and-fifth-liter-paired sample, suppliers must collect tap water in five consecutively numbered, wide-mouth, one-liter sample bottles after the water has stood motionless in the plumbing of each sampling site, including the lead service line, for at least six hours without flushing the tap prior to sample collection.  Suppliers must collect samples starting with the first sample bottle and then fill each subsequently numbered bottle in consecutive order until the final bottle is filled, with the water running constantly while the samples are being collected.  In this sequence, the first-liter sample is the first sample collected and the fifth-liter sample is the final sample collected. C)        Agency-approved samples collected under subsection (b)(3) may include samples with stagnation periods less than six hours, but must meet all the other sample collection criteria in this subsection (b)(1), including being one-liter in volume using a wide-mouth bottle and collected at an interior tap from which water is typically drawn for human consumption. D)        Suppliers may use different sample volumes and/or different sample collection procedures when they collect follow-up samples for Distribution System and Site Assessment under Section 611.352(j)(2) and consumer-requested samples under Section 611.355(c) to assess the source of lead.  Consumer-requested samples must be collected in compliance with Section 611.355(c).  Suppliers must submit these sample results to the Agency in compliance with Section 611.360 (a)(2)(A) and (g). 2)         Suppliers must sample at sites listed in the site sample plan.  Additionally, suppliers must prioritize sampling at the same sites that were sampled in the previous tap sampling period.  If such a site no longer qualifies under the tiering criteria or if, for reasons beyond the control of the supplier, the supplier cannot gain access to a sampling site in order to collect a tap sample, the supplier must collect the tap sample from another site in its site sample plan that meets the original tiering criteria, where such a site exists.  Suppliers must report any change in sites from the previous tap sampling period and include an explanation of why sampling sites have changed, as required in Section 611.360(a)(2)(E).  If changes are needed to the site sample plan, suppliers must submit their updated site sample plan, as required under Section 611.360(a)(1)(A), before the start of the next tap sampling period conducted by the supplier. 3)         A NTNCWS supplier, or a CWS supplier that meets the criteria of Section 611.355(b)(8) that does not have enough sites with taps from which first-liter samples or first-liter-and-fifth-liter-paired samples meeting the six-hour minimum stagnation time can be collected, as provided in subsection (b)(1), may apply to the Agency in writing to request approval to substitute first-liter or first-liter-and-fifth-liter-paired samples that do not meet the six-hour minimum stagnation time.  Such suppliers must collect as many first-liter or first-liter-and-fifth-liter-paired samples from interior taps used for human consumption as possible towards meeting the minimum number of sites required in subsections (c)(1) and (d)(1).  For the remaining samples to meet the minimum number required, suppliers must identify sampling times and locations that would likely result in the longest standing times.  The Agency has the discretion to waive the requirement for prior Agency approval of sites not meeting the six-hour stagnation time either through State regulation or written notification to the supplier. c)         Standard monitoring. Standard monitoring consists of six-month tap monitoring periods that begin on January 1 and July 1. 1)         Standard monitoring sites.  During a standard tap monitoring period, a supplier must collect at least one sample from the number of sites in the following table 1 to this subsection (c)(1).  Standard monitoring sites must be selected in compliance with the sampling tiers identified in subsection (a). Table 1 to Subsection (c)(1) System size (number of people served) Standard number of sites for lead and copper sampling >100,000 100 10,001 to 100,000 60 3,301 to 10,000 40 501 to 3,300 20 101 to 500 10 ≤100 5 2)         Criteria for standard monitoring.  The following suppliers must conduct standard monitoring for at least two consecutive tap monitoring periods beginning January 1 or July 1, whichever is sooner, following the tap sampling period in which the criterion is met. Suppliers may then reduce monitoring in compliance with subsection (d). A)        All suppliers with lead or galvanized requiring replacement service lines in their inventories as of November 1, 2027, including those deemed optimized under Section 611.351(b)(3) must conduct standard monitoring in the first six-month tap monitoring period following November 1, 2027, unless the supplier has, before or by that date, met all the following criteria: i)          The supplier conducts compliance monitoring of sites that meet the correct priority tiering targeting sites served by lead and galvanized requiring replacement service lines in compliance with subsection (a)(4); ii)         The supplier collects samples in compliance with all sample collection requirements in subsections (b)(1) and (3); and iii)        The supplier collects either first-liter samples or first-liter-and-fifth-liter- paired samples in compliance with subsection (b)(1). B)        Any supplier whose most recent 90 th percentile lead and/or copper results as of November 1, 2027, exceeds the lead and/or copper action level must conduct standard monitoring in the first six-month tap monitoring period following November 1, 2027. C)        Suppliers meeting any of the following criteria: i)          Any supplier that exceeds a lead or copper action level. ii)         Any supplier that fails to operate at or above the minimum value or within the range of values for the optimal water quality parameters designated by the Agency under Section 611.352(f) for more than nine days in any tap monitoring period as specified in Section 611.357. iii)        Any supplier that becomes a large water system without corrosion control treatment or any large water system without corrosion control treatment whose lead 90 th percentile exceeds the lead practical quantitation limit of 0.005 mg/L. iv)        Any supplier that installs OCCT or re-optimizes OCCT as a result of exceeding the lead or copper action level, or any supplier that adjusts OCCT following a Distribution System and Site Assessment.  Suppliers conducting standard monitoring under this criterion must continue standard monitoring until the Agency designates new optimal water quality parameters, at which point suppliers must comply with subsection (c)(2)(C)(v). v)         Any supplier the Agency has designated new values for optimal water quality parameters under Section 611.352. vi)        Any supplier that installs source water treatment pursuant to Section 611.353(a)(3). vii)       Any supplier that has notified the Agency in writing in compliance with Section 611.360(a)(4) of an upcoming addition of a new source or long-term change in treatment, unless the Agency 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. viii)      Any supplier without lead or galvanized requiring replacement service lines in its inventory that notifies the Agency under Section 611.360(e)(4)(B) of any subsequently discovered lead or galvanized requiring replacement service lines in its distribution system, unless the supplier replaces all the discovered service lines before the start of the next tap monitoring period. d)         Reduced monitoring based on 90 th percentile levels.  Reduced monitoring refers to an annual or triennial tap monitoring period.  Each annual or triennial tap monitoring period includes one tap sampling period.  The reduced monitoring frequency is based on the 90 th percentile value for the water system. 1)         Reduced monitoring sites.  During a reduced tap monitoring period, a supplier must collect at least one sample from the number of sites specified in table 1 to this subsection (d)(1), unless otherwise specified.  Reduced monitoring sites must be selected in compliance with the sampling tiers identified in subsection (a). Lead and copper sampling results collected from point-of-use sites under Section 611.363(c)(1) cannot be used to meet the criteria for reduced monitoring under this section. The Agency may specify the locations of sample sites when a supplier is conducting reduced monitoring. Table 1 to Subsection (d)(1) System size (number of people served) Reduced minimum number of sites for lead and copper sampling >100,000 50 10,001 to 100,000 30 3,301 to 10,000 20 501 to 3,300 10 101 to 500 5 ≤100 5 2)         Criteria for reduced monitoring.  Suppliers are eligible for reduced monitoring if they meet all the requirements of this section, including collecting at least the minimum number of samples required, for at least two consecutive tap monitoring periods.  The Agency may require an eligible supplier to conduct more frequent monitoring. A)        Annual monitoring for any supplier size.  Any supplier that does not exceed the lead and copper action levels and, for suppliers with Agency-designated OWQPs, also maintains the range of optimal water quality parameters designated by the Agency in compliance with Section 611.352(f) for two consecutive six-month tap monitoring periods may reduce the monitoring frequency to annual monitoring.  Suppliers with an annual tap monitoring period must sample at least the standard number of sampling sites for lead in subsection (c)(1) and at least the reduced number of sites for copper as specified in subsection (d)(1).  Prior to conducting annual monitoring, suppliers must receive a written determination from the Agency approving annual monitoring based on the Agency's review of monitoring, treatment, and other relevant information submitted by the supplier as required by Section 611.360.  For suppliers that reduce to annual monitoring, the first annual tap monitoring period must begin no later than six months following the last tap monitoring period. B)        Triennial monitoring for small and medium water suppliers.  Any small or medium water supplier that does not exceed the lead and copper action levels and, for suppliers with Agency-designated OWQPs, also maintains the range of optimal water quality parameters designated by the Agency in compliance with Section 611.352(f), during three consecutive years of monitoring, including monitoring conducted at both standard and annual frequencies (standard monitoring completed during both six-month periods of a calendar year is considered one year of monitoring), may reduce the monitoring frequency to triennial monitoring.  Suppliers on triennial monitoring must sample at least the reduced number of sites for lead and copper in compliance with subsection (d)(1).  Prior to conducting triennial monitoring, suppliers must receive a written determination from the Agency approving triennial monitoring based on the Agency's review of monitoring, treatment, and other relevant information submitted by the supplier as required by Section 611.360.  For suppliers that reduce to triennial monitoring, the first triennial tap monitoring period must immediately follow the last annual monitoring period, and the first triennial sampling period must begin no later than three calendar years after the last calendar year in which the supplier sampled. C)        Triennial monitoring for any supplier size.  Any supplier that demonstrates for two consecutive tap monitoring periods that its 90 th percentile lead level, calculated under Section 611.350(c)(3), is less than or equal to 0.005 mg/L, the 90 th percentile copper level, calculated under Section 611.350(c)(3), is less than or equal to 0.65 mg/L and, for suppliers with Agency-designated OWQPs, also maintains the range of optimal water quality parameters designated by the Agency in compliance with Section 611.352(f), may reduce the monitoring frequency to triennial monitoring.  Suppliers on triennial monitoring must sample at least the reduced number of sites for lead and copper in compliance with subsection (d)(1).  Prior to conducting triennial monitoring, suppliers must receive a written determination from the Agency approving triennial monitoring based on the Agency's review of monitoring, treatment, and other relevant information submitted by the supplier as required by Section 611.360.  For suppliers that reduce to triennial monitoring, the first triennial tap monitoring period must immediately follow the last monitoring period, and the first triennial tap sampling period must begin no later than three calendar years after the last calendar year in which the supplier sampled. 3)         Tap sampling period under reduced monitoring.  The tap sampling period for suppliers on reduced monitoring must occur within the months of June, July, August, or September, unless the Agency has approved a different tap sampling period in compliance with subsection (d)(3)(A).  Only suppliers on reduced monitoring can monitor during a tap sampling period that is shorter than the tap monitoring period. A)        The Agency may approve a different tap sampling period for suppliers collecting samples on reduced monitoring.  An alternative tap sampling period approved by the Agency must be a continuous period of time no longer than four consecutive months, must occur entirely within one calendar year, and must represent a time of normal operation where the highest levels of lead are most likely to occur.  For a NTNCWS supplier that does not operate during the months of June through September and for which the period of normal operation where the highest levels of lead are most likely to occur is not known, the Agency must designate a period that represents normal operation for the supplier. B) Suppliers that receive Agency-approval for an alternate tap sampling period under subsection (d)(3)(A) and have been sampling in the months of June through September must complete their next tap sampling period no later than 21 months, if on annual monitoring, or no later than 45 months, if on triennial monitoring, following the end of the previous tap sampling period. C)        Suppliers with waivers granted under subsection (g) that have been collecting samples during the months of June through September and receive Agency approval to alter their sampling period as per subsection (d)(3)(A) must collect their next round of samples before the end of the next nine-year period. e)         Inclusion of lead and copper tap samples for calculation of the 90 th percentile.  Suppliers and the Agency must consider the results of any sampling conducted in addition to the minimum number of samples required in subsections (c) or (d), as applicable, in making any determinations (i.e., calculating the 90 th percentile lead or copper level in compliance with Section 611.350(c)(3)) under this subpart if the samples meet the requirements of subsections (a) and (b).  Consumer-requested sampling conducted in compliance with Section 611.355(c) must be considered if the sample meets the requirements of subsections (a) and (b).  If multiple samples from the same site, taken during the same tap sampling period, meet the requirements of this section for consideration of the 90 th percentile calculation, only the highest value from each site can be considered, except for suppliers under section (a)(2). 1)         Suppliers sampling at one or more Tier 1 and/or Tier 2 sites in a tap sampling period that are unable to collect the minimum number of samples required in subsection (c) or (d) from Tier 1 or 2 sites must consider the lead and copper values from the next highest tier available in compliance with subsection (a).  If a supplier has sufficient samples after including the samples from the next highest available tier to meet the minimum number of samples required in subsection (c) or (d), the supplier may not consider additional samples from other available lower tiers.  Suppliers (or the Agency) must calculate the 90 th percentile lead and copper values in compliance with Section 611.350(c)(3)(C) using a total number of samples equal to the minimum number of samples required in subsection (c) or (d).  Suppliers must submit all additional sampling results to the Agency that were not used in the 90 th percentile calculation. 2)         Suppliers (or the Agency when the Agency is calculating the 90 th percentile) cannot include samples collected as part of Distribution System and Site Assessment under Section 611.352(j)(2) in the 90 th percentile calculation. 3)         Suppliers (or the Agency when the Agency is calculating the 90 th percentile) cannot include follow-up samples collected as a result of monitoring after service line replacement under Section 611.354(h) in the 90 th percentile calculation. f)         Invalidation of lead and copper tap samples used in calculating the 90 th percentile concentration .  A sample the Agency invalidates under this subsection (f) does not count towards determining lead or copper 90 th percentile concentrations under Section 611.350(c)(3) or towards meeting the minimum monitoring requirements of subsection (c) or (d).  The supplier must report the results of all samples to the Agency and all supporting documentation for samples the supplier believes should be invalidated. 1)         The Agency may invalidate a lead or copper tap water sample if at least one of the following conditions is met: A)        The laboratory establishes that improper sample analysis caused erroneous results. B)        The Agency determines that a sample collected for compliance purposes under this section, that is not an additional sample collected under subsection (e) was taken from a site that did not meet the site selection criteria under subsection (a), such as when sites of higher tier were still available. C)        The Agency determines the sample was collected in a manner that did not meet the sample collection protocol under subsection (b)(1). D)        The sample container was damaged in transit. E)        There is a substantial reason to believe that the sample was subject to tampering. 2)         To invalidate a sample under subsection (f)(1), the Agency must document in writing both the decision and the rationale for the decision.  The Agency may not invalidate a sample solely on the grounds that a follow-up sample result is higher or lower than that of the original sample. 3)         The supplier must collect replacement samples for any samples invalidated under this section if, after the invalidation of one or more samples, the supplier has too few samples to meet the minimum requirements of subsection (c)(1) or (d)(1).  Any such replacement samples must be taken as soon as possible, but no later than 20 days after the date the Agency notifies the supplier of an invalidated sample or by the end of the tap sampling period, whichever occurs later.  Replacement samples taken after the end of the applicable tap sampling period can only be used to meet the monitoring requirements of the applicable tap monitoring period in subsection (c) or (d) and not a subsequent tap monitoring period.  The replacement samples must be taken at the same locations as the invalidated samples, except when the sample is invalidated due to an error in meeting the site selection criteria under subsection (a), or a supplier cannot gain access for sampling.  The replacement samples must then be taken at locations that meet the site selection criteria other than those locations already used for sampling during the tap monitoring period. g)         Monitoring waivers for suppliers serving 3,300 or fewer persons..  Any supplier serving 3,300 or fewer persons complying with the criteria in this subsection (g) may apply, in writing, to the Agency to reduce the frequency of monitoring for lead and/or copper to once every nine years. The supplier must meet the materials criteria specified in subsection (g)(1) and all of the monitoring criteria specified in subsection (g)(2). Suppliers meeting only the criteria for lead may apply for a lead waiver, suppliers meeting only the criteria for copper may apply for a copper waiver, and suppliers meeting the criteria for both lead and copper may apply for a full waiver. 1)         Materials criteria.  The supplier must demonstrate that its distribution system, service lines, and all drinking water supply plumbing, including plumbing conveying drinking water within all residences and buildings connected to the system, are free of lead-containing materials and/or copper-containing materials, as those terms are defined in this subsection (g)(1) as follows: A)        Lead.  To qualify for a lead waiver, the supplier must certify and provide supporting documentation to the Agency demonstrating that its system including distribution system and all premise plumbing is free of all lead-containing materials as follows: i)          The system has no plastic pipes or service lines containing lead plasticizers; and ii)         The system is free of lead service lines, galvanized requiring replacement service lines, lead connectors, lead pipes, lead soldered pipe joints, and leaded brass- or bronze-alloy fittings and fixtures, unless such fittings and fixtures comply with Section 611.126(b). BOARD NOTE:  Corresponding 40 CFR 141.86(g)(1)(i)(B) specifies "any standard established under 42 U.S.C. 300g-6(e) (SDWA section 1417(e))". Congress changed the lead standards for fittings and fixtures in the Reduction of Lead in Drinking Water Act, P.L. 111-380, section 2(a)(2) and (b), 124 Stat. 4131 (Jan. 4, 2011).  The Board incorporated the statutory changes into this Section by referencing Section 611.126(b). B)        Copper.  To qualify for a copper waiver, the supplier must certify and provide supporting documentation to the Agency demonstrating that the system contains no copper service lines or premise plumbing. 2)         Monitoring criteria. The supplier must have completed at least one six-month round of standard tap water monitoring for lead and copper at sites approved by the Agency and from the number of sites required by subsection (c)(1) and demonstrate to the Agency that the 90 th percentile concentrations for any and all rounds of monitoring conducted since the system became free of all lead-containing or copper-containing materials, as appropriate, meet the following criteria: A)        Lead levels.  To qualify for a lead waiver, the supplier must demonstrate that its 90 th percentile lead concentration does not exceed 0.005 mg/L. B)        Copper levels.  To qualify for a copper waiver, the supplier must demonstrate that its 90 th percentile copper concentration does not exceed 0.65 mg/L. 3)         Agency approval of waiver application.  The Agency must notify the supplier of its waiver determination in writing stating the basis of its decision and any condition(s) of an approved waiver.  As a condition of a waiver, the Agency may require the supplier to perform specific activities (e.g., limited monitoring, periodic outreach to customers to remind them to avoid installing materials that might void the waiver) to avoid lead or copper concentrations of concern in tap water.  The supplier must continue monitoring for lead and copper at the tap as required by subsections(c) and (d), as appropriate, until the supplier receives written notification from the Agency that a waiver has been approved. 4)         Monitoring frequency for suppliers with waivers. A)        A supplier with a full waiver must conduct tap monitoring for lead and copper in compliance with subsection (d) at least once every nine years.  A supplier with a full waiver must provide the Agency with the materials certification specified in subsection (g)(1) for both lead and copper when submitting their tap sampling results to the Agency.  The supplier must collect samples every nine years no later than the ninth calendar year. B)        A supplier with a lead or copper waiver must conduct tap monitoring for only the waived contaminant in compliance with subsection (d) at least once every nine years.  A system with a lead waiver or copper waiver must provide the Agency with the materials certification specified in subsection (g)(1) for only the waived contaminant when submitting their tap sampling results to the Agency.  Also, a supplier must continue to monitor for the non-waived contaminant in compliance with the requirements of subsections (c) and (d) as appropriate. C)        A supplier with a waiver must notify the Agency in writing in compliance with Section 611.360(a)(4) about any addition of a new source water or  long-term change in treatment, as described in that section.  The Agency may add or modify waiver conditions (e.g., require recertification that the supplier's system is free of lead-containing or copper-containing materials, require additional rounds of monitoring, etc.) if the Agency determines that any modifications are necessary to address system treatment or source water changes at the supplier's system. D)        If a supplier with a waiver becomes aware that its system is no longer free of lead-containing or copper-containing materials, as appropriate (e.g., as a result of new construction or repairs), the supplier must notify the Agency in writing no later than 60 days after becoming aware of the change. 5)         Discontinuation of eligibility.  A supplier with a waiver where any of the following conditions occur is not allowed to continue monitoring under its waiver: A)        A supplier with a full waiver or a lead waiver no longer satisfies the materials criteria of subsection (g)(1)(A) or has a 90 th percentile lead concentration greater than 0.005 mg/L. B)        A supplier with a full waiver or a copper waiver no longer satisfies the materials criteria of subsection (g)(1)(B) or has a 90 th percentile copper concentration greater than 0.65 mg/L. C)        The Agency notifies the supplier in writing, that the waiver has been revoked, setting forth the basis of its decision. 6)         Requirements following waiver revocation.  A supplier whose waiver is revoked may reapply for a waiver when it meets the appropriate materials criteria and monitoring criteria of subsections (g)(1) and (2).  A supplier whose waiver is revoked by the Agency is subject to the following corrosion control treatment and lead and copper tap water monitoring requirements: A)        If the supplier exceeds the lead and/or copper action level, the supplier must implement or re-optimize OCCT in compliance with the deadlines specified in Section 611.351 and any other applicable requirements of this Subpart G. B)        If the supplier is at or below both the lead and copper action levels, the supplier must monitor for lead and copper at the tap no less frequently than once every three years using the reduced number of sampling sites specified in subsection (d)(1). 7)         Pre-existing waivers.  Waivers approved by  the Agency in writing prior to the compliance date specified in 611.350(a)(3) are still in effect if the supplier has demonstrated that it is both free of lead-containing and copper-containing materials, as required by subsection (g)(1) and that the supplier's 90 th percentile lead levels and 90 th percentile copper levels meet the criteria of subsection (g)(2), the supplier does not meet the waiver ineligibility criteria of subsection (g)(5). h) Publicly accessible tap monitoring results used in the 90 th percentile calculation.  Unless done by the Agency, all suppliers must make the tap monitoring results, including data used in the 90 th percentile calculation under Section 611.350(c)(3), publicly accessible within 60 days of the end of the tap sampling period.  Under this subsection (h), suppliers are not required to make the addresses of tap sampling sites publicly accessible. 1)         Large suppliers must make the tap monitoring results and associated data publicly accessible in a digital format. 2)         Small and medium suppliers must make the tap monitoring results and associated data publicly accessible in either a print or digital format. 3)         Suppliers must certify to the Agency, in writing, compliance with this subsection (h) in compliance with Section 611.360(a)(2)(C) and must retain monitoring data in compliance with the recordkeeping requirements under Section 611.361. BOARD NOTE:  This Section derives from 40 CFR 141.86.