How many coliform samples are required each month for a water system serving a population between 25 and 100?

For a water system serving a population between 25 and 100, the regulatory standard specifies that one coliform sample must be collected and analyzed each month. This requirement is based on ensuring adequate monitoring of the water quality to detect potential microbial contamination, particularly fecal coliform and E. coli, which are indicators of pathogen presence and overall water safety.

Collecting just one sample monthly is sufficient for this size of the population because it allows for cost-effective monitoring while still adhering to regulatory standards. In larger systems or systems serving greater populations, the number of required samples increases to ensure a higher level of surveillance due to the larger volume of water and potential sources of contamination. Therefore, for this specific range of population, the requirement remains at one sample per month to ensure compliance with health and safety regulations.