Section Env-Dw 711.20 - Revised Monitoring for Nitrate(a) The O/O of a community water system using groundwater, a non-transient non-community water system using groundwater, or a transient non-community water system using groundwater shall monitor for nitrate quarterly for at least one year following any one sample in which the concentration is greater than or equal to 50% of the nitrate MCL.(b) After a minimum of one year of quarterly sampling, the O/O may submit a written request to the department for the monitoring frequency to be reduced.(c) The written request shall include: (2) The PWS identifier for the PWS;(3) A summary of all quarterly sampling results; and(4) An explanation of whether the PWS is operating any type of treatment to reduce the amount of nitrate.(d) The department shall approve a reduction in monitoring from quarterly to annually if the department determines that:(1) Based on 4 consecutive quarterly samples, the nitrate levels are reliably and consistently below the nitrate MCL; and(2) The PWS is not operating any type of treatment to reduce the amount of nitrate.(e) A surface water system shall return to quarterly monitoring if any one sample is greater than or equal to 50% of the nitrate MCL.(f) After the initial round of quarterly sampling is completed, each community water system, non-transient non-community water system, and transient non-community system shall collect subsequent annual samples during the quarter in which the highest analytical result was obtained.N.H. Code Admin. R. Env-Dw 711.20
(See Revision Note #1 at chapter heading for Env-Dw 700) #9700, eff 5-1-10
Amended by Volume XXXV Number 06, Filed February 12, 2015 , Proposed by #10771, Effective 2/1/2015, Expires2/1/2025.Amended by Volume XXXVIII Number 50, Filed December 13, 2018, Proposed by #12668, Effective 1/1/2019, Expires 1/1/2029.