Section Env-Ws 381.21 - Reduced and Additional Lead and Copper Monitoring(a) The owner of a small or medium-size water system meeting the lead and copper action levels during each of 2 consecutive 6-month monitoring periods may reduce the number of samples in accordance with Env-Ws 381.17(b), and reduce the frequency of sampling to once per year.(b) A water system owner maintaining the range of values for the water quality parameters reflecting optimal corrosion control treatment specified by the department under Env-Ws 381.10(e) and (f) during each of 2 consecutive 6-month monitoring periods, may reduce the frequency of monitoring to once per year and reduce the number of lead and copper samples in accordance with Env-Ws 381.17(b) if the water system receives written approval from the department.(c) The department, in making its determination in (b) above, shall review the following: (1) Water quality parameter results;(2) Type of treatment used; and(3) Any other information submitted to the department pursuant to Env-Ws 381.33.(d) If the department determines that the system's sampling results for the treatment installed is at or above the minimum value or within the range of values for the water quality parameters specified Env-Ws 381.10, the department shall notify the system owner in writing that the system is eligible for reduced monitoring.(e) The department shall review and revise its determination when the system owner submits new monitoring or treatment data, or when other data relevant to the number and frequency of tap sampling becomes available.(f) The owner of a small or medium-size water system meeting the lead and copper action levels during 3 consecutive years of monitoring may reduce the frequency of monitoring for lead and copper from annually to once every 3 years.(g) A water system owner maintaining the range of values for the water quality control parameters reflecting optimal corrosion control treatment specified by the department under Env-Ws 381.10(e) and (f) during 3 consecutive years of monitoring may reduce the frequency of monitoring from annually to once every 3 years if they receive written approval from the department.(h) The department, in making its determination in (g) above, shall review the following: (1) Water quality parameter results;(2) Type of treatment used; and(3) Any other information submitted to the department pursuant to Env-Ws 381.33.(i) If the department determines that the system's sampling results for the treatment installed is at or above the minimum value or within the range of values for the water quality parameters specified Env-Ws 381.10, the department shall notify the system owner in writing that the system is eligible for reduced monitoring. The department shall review and revise its determination when the system owner submits new monitoring or treatment data, or when other data relevant to the number and frequency of tap sampling becomes available.(j) A water system owner reducing the number of samples and frequency of sampling shall collect these samples from representative sites included in the pool of targeted sampling sites identified in Env-Ws 381.15. A water system sampling annually or less frequently shall conduct the lead and copper tap sampling during the months of June, July, August or September unless the department has approved a different sampling period in accordance with (k) through (m), below.(k) The department shall approve a different period for conducting lead and copper tap sampling for a system owner collecting a reduced number of samples if the period during which samples normally would be collected is not representative of a time of normal operation for the system.(l) The period in (k) above, shall be no longer than 4 consecutive months and shall represent a time of normal operation where the highest levels of lead are most likely to occur.(m) For a non-transient non-community water system 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 department shall designate a period that represents a time of normal operation for the system.(n) A system owner monitoring annually who has been collecting samples during the months of June through September and who receives department approval to alter the sample collection period under (k) through (m) above, shall collect the next round of samples during a time period that ends no later than 21 months after the previous round of sampling.(o) A system owner monitoring triennially who has been collecting samples during the months of June through September and who receives department approval to alter the sampling collection period under (k) above, shall collect the next round of samples during a time period that ends no later than 45 months after the previous round of sampling. Subsequent rounds of sampling shall be collected annually or triennially, as required by this part.(p) An owner of any size water system that demonstrates for 2 consecutive 6-month monitoring periods that the tap water lead level calculated pursuant to Env-Ws 381.03 is less than or equal to 0.005 mg/L and the tap water copper level calculated pursuant to Env-Ws 381.03 is less than or equal to 0.65 mg/L may reduce the number of samples in accordance with Env-Ws 381.17 and reduce the frequency of sampling to once every 3 calendar years.(q) The owner of a small or medium-size water system subject to reduced monitoring that exceeds the lead or copper action level shall resume sampling in accordance Env-Ws 381.20 and shall collect the number of samples specified for standard monitoring under Env-Ws 381.17. Such system owner shall also conduct water quality parameter monitoring in accordance with Env-Ws 381.22 during the monitoring period in which it exceeds the action level.(r) A water system owner in (q) above may:(1) Resume annual monitoring for lead and copper at the tap at the reduced number of sites specified in Env-Ws 381.17 after having completed 2 subsequent consecutive 6-month rounds of monitoring that meet the criteria of (a) above; or(2) Resume triennial monitoring for lead and copper at the reduced number of sites, upon receipt of written approval from the department, which shall be granted after the water system demonstrates through subsequent rounds of monitoring that: a. The water system meets the requirements of Env-Ws 381.21(f); orb. The water system meets the requirements of Env-Ws 381.21(g).(s) The results of any monitoring conducted in addition to the minimum requirements of Env-Ws 381.15 through Env-Ws 381.21 shall be considered by the system owner and the department in calculating the 90th percentile lead or copper level.(t) The owner of a water system monitoring at a reduced frequency that fails to operate at or above the minimum value or within the range of values for the water quality parameters as specified under Env-Ws 381.10 for more than 9 days in any 6-month period as specified in Env-Ws 381.26 shall: (1) Conduct tap water sampling for lead and copper at the frequency specified in Env-Ws 381.20; and(2) Collect the number of samples specified for standard monitoring in accordance with Env-Ws 381.17.(u) A water system owner in (t) above may resume annual monitoring for lead and copper at the tap and for water quality parameters within the distribution system at the reduced number of sites as specified in Env-Ws 381.17 after the system: (1) Completes 2 subsequent 6-month rounds of monitoring that meet the criteria of (b) and (c) above; and(2) Submits a written request to the department to resume reduced monitoring on an annual frequency.(v) A system owner may resume triennial monitoring for lead and copper at the tap at a reduced number of sites after the system: (1) Demonstrates through subsequent rounds of monitoring that it meets the criteria of (d) through (f) or (i) above; and(2) Submits a written request to the department to resume triennial monitoring.(w) The written request to reduce monitoring in (u) and (v) above shall: (1) Identify the system name;(2) Identify the system identification number; and(3) Explain the rationale for the request.(x) The department shall respond to the request in writing and shall approve the request if it finds that the system has met the monitoring criteria specified in (u)(1) or (v)(1) above.(y) A water system owner may reduce the number of water quality parameter tap water samples required in Env-Ws 381.27(a) and (b) and the frequency with which it collects such samples in accordance with Env-Ws 381.27(c) and (d). Such a system shall not resume triennial monitoring for water quality parameters at the tap until it demonstrates, in accordance with Env-Ws 381.27(c) and (d) that it has re-qualified for triennial monitoring.(z) The owner of a water system subject to a reduced monitoring frequency under Env-Ws 381.21 that either adds a new source of water or changes any water treatment shall notify the department in writing within 60 days. The department shall require the system to resume sampling in accordance with Env-Ws 381.20 and collect the number of samples specified for standard monitoring under Env-Ws 381.17(a) or take other appropriate steps such as increased water quality parameter monitoring or re-evaluation of its corrosion control treatment given the potentially different water quality considerations if the system fails to meet the lead or copper action levels specified in Env-Ws 381.03.N.H. Admin. Code § Env-Ws 381.21
#5422 eff 6-22-92; amd by #5873, eff 7-26-94; ss by #6521, eff 6-4-97 (See Revision Note at chapter heading for Env-Ws 300) ss by #7734, eff 8-2-02; amd by #8351, eff 5-14-05