1. (1) General.

   1. (a) The provisions of this section apply to public water systems serving more than 1,000 persons.
   2. (b) Following any total coliform-positive sample taken under the provisions of this section, systems must comply with the repeat monitoring requirements and E. coli analytical requirements in R309-211-7.
   3. (c) Once all monitoring required by this section and R309-211-7 for a calendar month has been completed, systems must determine whether any coliform treatment technique triggers specified in R309-211-8 have been exceeded. If any trigger has been exceeded, systems must complete assessments as required by R309-211-8.

   4. (d) Seasonal systems.

      1. (i) Beginning April 1, 2016, all seasonal systems must demonstrate completion of a Director-approved start-up procedure, which may include a requirement for start-up sampling prior to serving water to the public.
      2. (ii) The Director may exempt any seasonal system from some or all of the requirements for seasonal systems if the entire distribution system remains pressurized during the entire period that the system is not operating.

2. (2) Monitoring frequency for total coliforms. The monitoring frequency for total coliforms is based on the population served by the system, as follows:

   TABLE 211-1

   Total Coliform Monitoring Frequency for

   Public Water Systems

   Minimum number of

   Population served samples per month

   25 to 1,000 1

   1,001 to 2,500 2

   2,501 to 3,300 3

   3,301 to 4,100 4

   4,101 to 4,900 5

   4,901 to 5,800 6

   5,801 to 6,700 7

   6,701 to 7,600 8

   7,601 to 8,500 9

   8,501 to 12,900 10

   12,901 to 17,200 15

   17,201 to 21,500 20

   21,501 to 25,000 25

   25,001 to 33,000 30

   33,001 to 41,000 40

   41,001 to 50,000 50

   50,001 to 59,000 60

   59,001 to 70,000 70

   70,001 to 83,000 80

   83,001 to 96,000 90

   96,001 to 130,000 100

   130,001 to 220,000 120

   220,001 to 320,000 150

   320,001 to 450,000 180

   450,001 to 600,000 210

   600,001 to 780,000 240

   780,001 to 970,000 270

   970,001 to 1,230,000 300

   1,230,001 to 1,520,000 330

   1,520,001 to 1,850,000 360

   1,850,001 to 2,270,000 390

   2,270,001 to 3,020,000 420

   3,020,001 to 3,960,000 450

   3,960,001 or more 480

KEY: drinking water, distribution system monitoring, total coliform, compliance determinations

Date of Last Change: January 15, 2019

Notice of Continuation: February 10, 2025

Authorizing, and Implemented or Interpreted Law: 19-4-104