New Hampshire Code of Administrative Rules
Env - Department of Environmental Services
Subtitle Env-Ws - Division of Water
Chapter Env-Ws 300 - NEW HAMPSHIRE DRINKING WATER RULES
Part Env-Ws 381 - CORROSION CONTROL TREATMENT, LEAD AND COPPER ACTION LEVELS
Section Env-Ws 381.28 - Monitoring For Lead and Copper In Source Water

(a) The owner of a water system failing to meet the lead or copper action level on the basis of tap samples collected in accordance with Env-Ws 381.15 through Env-Ws 381.21, shall collect lead and copper source water samples in accordance with the following requirements:

(b) If a system draws water from more than one source and the sources are combined before distribution, the system owner shall sample at an entry point to the distribution system during periods when water is representative of all sources being used.

(c) If the department determines that a water system may composite samples, such compositing shall be completed by an accredited laboratory or certified laboratory.

(d) The timing of sampling for lead and copper shall be in accordance with (h) below, and Env-Ws 381.29(a) and not the dates specified in Env-Ws 326.01 through Env-Ws 326.12.

(e) Where the results of sampling indicate an exceedance of maximum permissible source water levels established under Env-Ws 381.12, the system owner shall collect one additional sample at the same sampling point as soon as practicable but no later than 14 days from the date sample was collected.

(f) The results of the initial and confirmation sample shall be averaged in determining compliance with the department-specified maximum permissible levels.

(g) Any sample value below the detection limit shall be considered to be zero.

(h) A system owner exceeding the lead or copper action level at the tap shall collect one source water sample from each entry point to the distribution system within 6 months after the exceedance.