If your system is a subpart H system serving fewer than 10,000 people and utilizing conventional filtration or direct filtration, you must conduct continuous monitoring of turbidity for each individual filter at your system. The following requirements apply to continuous turbidity monitoring:
(a) Monitoring must be conducted using an approved method in Sec. 141.74(a);
(b) Calibration of turbidimeters must be conducted using procedures specified by the manufacturer;
(c) Results of turbidity monitoring must be recorded at least every 15 minutes;
(d) Monthly reporting must be completed according to Sec. 141.570; and
(e) Records must be maintained according to Sec. 141.571.