Section Env-Dw 709.15 - Repeat Monitoring(a) Subject to (b) and (c), below, if a routine sample is positive for total coliforms the PWS owner shall collect a set of not less than 3 repeat samples as specified in (d) and (f), below, for each routine sample that was positive for total coliforms within 24 hours after being notified of the positive result.(b) If one or more of the samples in a set of repeat samples is positive for total coliforms, the PWS owner shall continue to collect additional sets of 3 samples every 24 hours until either: (1) Total coliforms are not detected in any sample in a set of 3 repeat samples; or(2) The coliform treatment technique trigger specified in Env-Dw 709.22 has been exceeded.(c) The department shall extend the 24-hour limit if the department determines that the PWS owner cannot collect the repeat samples within 24 hours or when the samples cannot be analyzed within 30 hours of being collected. In determining the amount of the time extension, the department shall evaluate the need to protect public health against the owner's inability to collect the samples within the 24-hour limit.(d) Subject to Env-Dw 709.16, the PWS owner shall collect one repeat sample from each of the following locations:(1) The sampling tap where the original sample that was positive for total coliforms was collected;(2) A tap within 5 service connections upstream of the original sampling site; and(3) A tap within 5 service connections downstream of the original sampling site.(e) The PWS owner shall collect a source sample to meet the triggered monitoring requirements specified in Env-Dw 717, if applicable.(f) The PWS owner shall collect all samples in a set of repeat samples on the same day.(g) Except as provided in Env-Dw 709.17, the department shall not waive the requirement for a system owner to collect repeat samples as specified in (a) through (f), above.N.H. Code Admin. R. Env-Dw 709.15
(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.