R 325.10726 Radionuclides; initial monitoring for gross alpha particle activity, radium-226, radium-228, and uranium.

Rule 726. (1) A community water supply shall conduct initial monitoring for gross alpha particle activity, radium-226, radium-228, and uranium to determine compliance with R 325.10603(2)(a), (b), and (d). (2) An existing supply shall sample at every entry point to the distribution system that is representative of all sources of water being used, known as "sampling point," under normal operating conditions. The supply shall take each sample at the same sampling point unless conditions make another sampling point more representative of each source. (3) A new community water supply or a community water supply that uses a new source of water shall begin to conduct initial monitoring for the new source within the first quarter after initiating use of the source. A community water supply shall conduct more frequent monitoring when ordered by the department if possible contamination or if changes in the distribution system or treatment processes occur which may increase the concentration of radioactivity in finished water. (4) A supply shall conduct initial monitoring for gross alpha particle activity, radium-226, radium-228, and uranium in the following manner: (a) A supply shall collect 4 consecutive quarterly samples at all sampling points before December 31, 2007. A supply that has results of samples collected from a sampling point during the compliance period that began between June 1, 2000 and December 8, 2003, may use those results to satisfy the initial monitoring requirements for that sampling point. (b) For gross alpha particle activity, uranium, radium-226, and radium-228 monitoring, the department may waive the final 2 quarters of initial monitoring for a sampling point if the results of the samples from the previous 2 quarters are below the detection limit. (c) If the average of the initial monitoring results for a sampling point is above the MCL, then the supply shall collect and analyze quarterly samples at that sampling point until the supply has results from 4 consecutive quarters that are at or below the MCL, unless the supply enters into another schedule as part of a formal compliance agreement with the department.