Section R. 325.10704h - Total coliform; repeat monitoring; E. coliRule 704h.
(1) Total coliform rules repeat monitoring requirements are all of the following: (a) If a sample taken under R 325.10704d to R325.10704g is total coliform-positive, the supply shall collect a set of repeat samples within 24 hours of being notified of the positive result. The supply shall collect not fewer than 3 repeat samples for each total coliform-positive sample found. The department may extend the 24-hour limit on a case-by-case basis if the supply has a logistical problem in collecting the repeat samples within 24 hours that is beyond its control. In the case of an extension, the department shall specify how much time the system has to collect the repeat sample. The department shall not waive the requirement for a supply to collect repeat samples in this subdivision and subdivisions (b) to (c) of this subrule.(b) The supply shall collect all repeat samples on the same day, except that the department may allow a supply with a single service connection to collect the required set of repeat samples over a 3-day period or to collect a larger volume repeat sample or samples in 1 or more sample containers of any size, as long as the total volume collected is at least 300 ml.(c) The supply shall collect an additional set of repeat samples in the manner specified in subdivisions (a) and (b) and this subdivision of this subrule if 1 or more repeat samples in the current set of repeat samples is total coliform-positive. The supply shall collect the additional set of repeat samples within 24 hours of being notified of the positive result, unless the department extends the limit under subdivision (a) of this subrule. The supply shall continue to collect additional sets of repeat samples until either total coliforms are not detected in 1 complete set of repeat samples or the supply determines that a coliform treatment technique trigger specified in R 325.10704i(1) has been exceeded as a result of a repeat sample being total coliform-positive and notifies the department. If a trigger identified in R 325.10704i is exceeded as a result of a routine sample being total coliform-positive, the supply shall conduct 1 round of repeat monitoring, but is not required to conduct more than 1 round of repeat monitoring for each total coliform-positive routine sample.(d) After a supply collects a routine sample and before it learns the results of the analysis of that sample, if it collects another routine sample or samples from within 5 adjacent service connections of the initial sample, and the initial sample, after analysis, is found to contain total coliforms, then the supply may count the subsequent sample or samples as a repeat sample instead of as a routine sample. (e) Results of all routine and re peat samples taken under R 325.10704d to R 325.10704h not invalidated by the department shall be used to determine whether a coliform treatment technique trigger in R 325.10704i has been exceeded.(2) Escherichia coli (E. coli) testing requirements are both of the following: (a) If a routine or repeat sample is total coliform-positive, the supply shall analyze that total coliform-positive culture medium to determine if E. coli are present. If E. coli are present, the supply shall notify the department by the end of the day when the supply is notified of the test result, unless the supply is notified of the result after the department office is closed and the department does not have either an after-hours phone line or an alternative notification procedure, in which case the supply shall notify the department before the end of the next business day.(b) The department may allow a supply, on a case-by-case basis, to forgo E. coli testing on a total coliform-positive sample if the supply assumes that the total coliform-positive sample is E. coli-positive. Accordingly, the supply shall notify the department under subdivision (a) of this subrule and the E. coli maximum contaminant level provisions of R 325.10602(1) apply.Mich. Admin. Code R. 325.10704h
2015 MR 20, Eff. 10/16/2015