12VAC5-590-770: Sampling and monitoring equipment

A. Sample taps shall be provided so that water samples can be obtained from each source water and each entry point to the distribution system. At waterworks providing treatment, sample taps shall be provided at the entrance and exit of each unit treatment process and at the entry point to the distribution system.

1. For surface water treatment plants, a master control sink shall monitor source water, chemically treated water, settled water, combined filter water, and at the entry point to the distribution system.

2. All sample taps shall discharge in the downward direction and be provided with a suitable air gap to prevent cross-connection.

B. Continuous monitoring instrumentation shall have electronic sensors that continuously read the parameter and shall display results in real time. Continuous recording equipment shall be provided with the monitoring instrument to store in memory or print one data point at least every 15 minutes. Each result shall be a single result at that time; if signal averaging is applied, the averaging period shall not exceed 30 seconds. The recording equipment shall be capable of producing a paper copy or equivalent electronic file showing daily trends, including maximum, minimum, and average values.