Section 22.07C - Unregulated Inorganic and Organic Chemicals Special Monitoring(1)Monitoring for Unregulated Organic and Inorganic Contaminants. The Monitoring frequency for the contaminants listed in 310 CMR 22.07C(5), (7) and (8) shall be as follows. (a)Sampling for Synthetic Organic Contaminants. Reserved.(b)Sampling for Inorganic Contaminants. Reserved.(c)Sampling for Volatile Organic Contaminants. Each community and non-transient non-community water system shall take one sample at each sampling point for each contaminant listed in 310 CMR 22.07C(5) and report the results to the Department. Monitoring shall be completed at the same time as routine VOC sampling in accordance with 310 CMR 22.07B.(2)Sampling Locations. The sampling for the contaminants listed in 310 CMR 22.07C shall be conducted as follows: (a)Ground Water Sampling Protocols. Groundwater systems shall take a minimum of one sample at every entry point to the distribution system which is representative of each well after treatment (sampling point). Each sample shall be taken at the same sampling point, unless conditions make another sampling point more representative of each source or treatment plant.(b)Surface Water Sampling Protocols. Surface water systems including, but not limited to, surface water systems with a combination of surface and ground sources shall take a minimum of one sample at points in the distribution system that are representative of each source or at each entry point to the distribution system after treatment (sampling point). Each sample shall be taken at the same sampling point, unless conditions make another sampling point more representative of each source or treatment plant.(c)Multiple Sources. If the system draws water from more than one source and the sources are combined before distribution, the system shall sample at an entry point to the distribution system during periods of normal operating conditions (i.e., when water representative of all sources is being used).(d)Confirmation Sampling. The Department may require a confirmation sample for positive or negative results.(e)Composite Sampling. The Department may reduce the total number of samples a system shall analyze by allowing the use of compositing. Composite samples from a maximum of five sampling points are allowed, provided that the detection limit of the method used for analysis is less than 1/5 of the MCL. Compositing of samples shall be done in the laboratory and the composite sample shall be analyzed within 14 days of collection and comply with 310 CMR 22.07B(6)(a) through (e). If the population served by the system is >3,300 persons, then compositing may only be permitted by the Department at sampling points within a single system. In systems serving <=3,300 persons, the Department may permit compositing among different systems provided the five-sample limit is maintained.(3)Unregulated Inorganic and Organic Chemical Special Monitoring. (Reserved)(4)Sampling Waivers. Each community and non-transient non-community water system may apply to the Department for a waiver from the requirements of 310 CMR 22.07C(l)(a), (b) and (c). Basis of Sampling Waivers. The Department may grant a waiver for the monitoring requirement of 310 CMR 22.07C(5) based on the criteria specified in 310 CMR 22.07B(3)(a). Waivers for monitoring requirements of 310 CMR 22.07C(7) are based on the criteria specified in 310 CMR 22.07 A(4). The Department may grant a waiver from the requirement of 310 CMR 22.07C(8) if previous analytical results indicate contamination would not occur, provided this data was collected after January 1, 1990.
(5)Unregulated VOC Contaminants. Methyl tert-butyl ether (MTBE)(6)EPA Analytical Methods for Unregulated VOC Contaminants. Analysis for the contaminants listed in 310 CMR 22.07C(5) shall be conducted using the recommended EPA methods at 310 CMR 22.07B(8).(7)Unregulated Synthetic Organic Contaminants and Analytical Methods. 1,4-Dioxane: EPA Method 522: Determination of 1,4-Dioxane in Drinking Water by Solid Phase Extraction (SPE) and Gas Chromatography/Mass Spectrometry (GC/MS) with Selected Ion Monitoring (SIM), EPA/600/R-08/101, Version 1.0, September 2008.(8)Unregulated Inorganic Contaminants and Analytical Methods. Reserved.(9)Repeat Monitoring. All community and non-transient, non-community water systems shall repeat the monitoring for contaminants listed in 310 CMR 22.07C(5) no less frequently than every three years or in accordance with the sampling frequencies in 310 CMR 22.07(B).(10)Unregulated Inorganic and Organic Chemical Special Monitoring. (Reserved)(11) Analysis under 310 CMR 22.07C shall be conducted by laboratories approved under 310 CMR 42.00: Certification and Operation of Environmental Analysis Laboratories using the recommended EPA methods listed at 310 CMR 22.07A (10). Amended by Mass Register Issue 1309, eff. 3/25/2016.Amended by Mass Register Issue 1419, eff. 6/12/2020.