Current through Register No. 50, December 12, 2024
Section Env-Ws 382.13 - Monitoring Requirements for Disinfection Byproduct Precursors(a) An owner of a SW/GWUDISW system using conventional filtration treatment shall conduct routine monitoring at each treatment plant for TOC prior to the point of combined filter effluent turbidity monitoring and representative of the treated water.(b) A system owner required to monitor for disinfection byproduct precursors under this section shall monitor for TOC in untreated source water at the same time as monitoring for TOC in the treated water.(c) A system owner shall, at the same time as the source water sample is collected, monitor for alkalinity in the source water prior to any treatment.(d) A system owner shall collect one paired sample and one source water alkalinity sample per month, per plant, at a time representative of normal operating conditions and influent water quality.(e) After a minimum of one year of monthly sampling, a SW/GWUDISW system owner may submit a written request to the department to reduce the monitoring frequency.(f) The request shall include: (2) The system EPA number; and(3) A summary of all treated water TOC sampling results.(g) The department shall respond to the request in writing and reduce the monitoring frequency for TOC and alkalinity to one paired sample and one source water alkalinity sample per plant per quarter if: (1) The average TOC of treated water is less than 2.0 mg/L for 2 consecutive years; or(2) The average TOC of treated water is less than 1.0 mg/L for one year.(h) A system on reduced monitoring shall revert to routine monitoring as specified in this section in the month following the quarter when the annual average treated water TOC is greater than or equal to 2.0 mg/L.N.H. Admin. Code § Env-Ws 382.13
(See third Revision Note at chapter heading Env-Ws 300); #7735, eff 8-2-02