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 381.25 - Monitoring Water Quality Parameters After Installation of Corrosion Control
Current through Register No. 13, March 27, 2025
(a) A large system owner installing optimal corrosion control treatment pursuant to Env-Ws 381.07 shall measure water quality control parameters at the locations and frequencies specified in (c) and (d) below during each 6-month monitoring period specified in Env-Ws 381.19(a).
(b) A small or medium-size system owner installing optimal corrosion control treatment shall monitor the water quality control parameters at the locations and frequencies specified in (c) and (d) below, during each 6-month monitoring period specified in Env-Ws 381.19(b) in which the system exceeds the lead or copper action level.
(c) Sample parameters taken at taps shall include 2 samples for:
(d) Except as provided in Env-Ws 381.23(c), (d), and (e), at each entry point to the distribution system, one sample shall be collected at least every 2 weeks for pH.
(e) When alkalinity is adjusted as part of optimal corrosion control, the system owner shall document the dosage r ate of the chemical used to adjust alkalinity and the alkalinity concentration.
(f) When a corrosion inhibitor is used as part of optimal corrosion control, the system owner shall document the dosage rate of the inhibitor used and the concentration of orthophosphate, silica, or other corrosion inhibitor.
(See Revision Note at chapter heading for Env-Ws 300) #6521, eff 6-4-97, ss by #7734, eff 8-2-02; amd by #8351, eff 5-14-05