Section 18 AAC 80.660 - Monitoring requirements for systems avoiding filtrationThe requirements of 40 C.F.R. 141.74(b), adopted by reference in 18 AAC 80.010(a), and of 18 AAC 80.655 apply to a community water system, non-transient non-community water system, or transient non-community water system that uses a surface water source or a GWUDISW source, and that does not provide filtration treatment. In addition,
(1) the department will require that a system that uses a GWUDISW source, that does not provide filtration treatment, and that is seeking to avoid filtration under 40 C.F.R. 141.71, adopted by reference under 18 AAC 80.010(a), begin monitoring in accordance with 40 C.F.R. 141.74(b) six months after the department determines that the groundwater source is under the direct influence of surface water;(2) the department will allow the system to substitute continuous turbidity monitoring for grab sample monitoring if the operator validates the continuous measurement for accuracy on a regular basis using a method approved under 18 AAC 80.655(c);(3) for 40 C.F.R. 141.74(b)(3)(v) for a system using a disinfectant other than chlorine, the owner shall demonstrate to the department, through standard sanitary engineering practices and principles, that CT99.9 values other than those specified in Tables 2.1 and 3.1 in 40 C.F.R. 141.74(b)(3) or other operational parameters are adequate to demonstrate that the system is achieving the minimum inactivation rates required by 40 C.F.R. 141.72(a)(1), adopted by reference in 18 AAC 80.010(a);(4) the requirements in 40 C.F.R. 141.74(b)(1), for one fecal or total coliform density measurement every day the system serves water to the public and the turbidity of the source water exceeds one NTU, apply unless the department finds that the owner or operator, for logistical reasons outside the owner's or operator's control, cannot have the sample analyzed within 30 hours after collection, or within 48 hours after collection for an area described in 18 AAC 80.350(a); if the logistical problem is likely to persist, the department will grant a standing waiver that will remain in effect until the department rescinds or revises it; the department will keep a copy of the waiver in the department's file for the public water system until one year after the waiver expires or is rescinded or revised; the department will not grant a waiver from the requirement of this section because of a lack of sampling containers; for purposes of this paragraph, the department will consider any of the following situations to be logistical reasons outside the owner's or operator's control: (A) the certified laboratories available to the system cannot analyze the samples within 30 hours after collection, or within 48 hours after collection for an area described in 18 AAC 80.350(a), because of limited days of operation or limited laboratory capacity;(B) weather conditions make it impossible to ship the samples to the laboratory for analysis within 30 hours after collection, or within 48 hours after collection for an area described in 18 AAC 80.350(a);(C) shipping services from the system are limited so that samples cannot be collected, shipped, and analyzed within 30 hours, or within 48 hours for an area described in 18 AAC 80.350(a);(D) other unusual or unpredictable situations, such as a landslide closing the road or knocking out a transmission line, make it impossible for the owner or operator to meet the 30-hour or 48-hour requirement;(5) if a circumstance described in (4)(B) - (D) of this section prevents heterotrophic plate count (HPC) sample analysis, (A) the owner who routinely uses HPC measurements instead of distribution system disinfectant residual measurements shall notify the department; a notification must include (i) a description of how the owner routinely has HPC samples analyzed;(ii) the specific reason a sample cannot be analyzed as required;(iii) a proposed disinfectant residual measurement or other plan to be used to confirm adequate disinfection in the distribution system;(iv) a summary of disinfectant concentrations entering the distribution system; and(v) system coliform results for the preceding month;(B) the department will confirm that the circumstance described in (4)(B) - (D) of this section prevents HPC sample analysis and will specify an alternate method to assure adequate system disinfection by adopting or modifying the proposal submitted by the owner or specifying another method; an alternate method of assuring adequate disinfection in the absence of HPC samples will usually involve monitoring system disinfection levels as prescribed by 40 C.F.R. 141.70 - 141.76, adopted by reference in 18 AAC 80.010(a);(C) the department will disallow the HPC method if HPC analysis is prevented for more than five percent of the required samples in any one-year period, and the department will require monitoring of system disinfectant concentrations, if disallowing the HPC method and requiring monitoring serves the interests of public health; the department will notify the owner of a decision to disallow the HPC method.Eff. 10/1/99, Register 151; am 3/25/2001, Register 157; am 4/24/2009, Register 190Guidance on standard sanitary engineering practices and principles, as addressed in 18 AAC 80.660(3), may be found in the department's Alaska Water Treatment Guidance Manual. Information about how to review or obtain this document is in the editor's note to 18 AAC 80.010.
Authority:AS 46.03.020
AS 46.03.050
AS 46.03.070
AS 46.03.710
AS 46.03.720