Rule 391-3-5-.27 - Monitoring Frequency and Analytical Methods for Radioactivity in Community Water Systems(1)Monitoring Requirements for Gross Alpha Particle Activity, Radium-226, Radium-228, and Uranium.(a) Compliance with Rule 391-3-5-.18(5) shall be based on the analysis of an annual composite of four consecutive quarterly samples or the average of the analyses of four samples obtained at quarterly intervals. 1. A gross alpha particle activity measurement may be substituted for the required Radium-226 and Radium-228 analysis provided that the measured gross alpha particle activity does not exceed 5 pCi/L, at a confidence level of 95 percent (1.65 [LOWER CASE SIGMA], where [LOWER CASE SIGMA] [sigma] is the standard deviation of the net counting rate of the sample). In localities where Radium-228 may be present in drinking water, Radium-226 and/or Radium-228 analyses are required when the gross alpha particle activity exceeds 2 pCi/L.2. When the gross alpha particle activity exceeds 5 pCi/L, the same or an equivalent sample shall be analyzed for Radium-226. If the concentration of Radium-226 exceeds 3 pCi/L the same or an equivalent sample shall be analyzed for Radium-228.(b) The initial analysis required by subparagraph (1)(a) for new water systems shall be completed within two years from the effective date of the permit to operate.(c) Suppliers of water shall monitor at least once every four years following the procedure required by subparagraph (1)(a). At the discretion of the Director when an annual record taken in conformance with subparagraph (1)(a) has established that the average annual concentration is less than half the maximum contaminant levels established by Rule 391-3-5-.18(6), analysis of a single sample may be substituted for the quarterly sampling procedure required by subparagraph (1)(a). 1. More frequent monitoring shall be conducted when ordered by the Director in the vicinity of mining or other operations which may contribute alpha particle radioactivity to either surface or ground water sources of drinking water.2. A supplier of water shall monitor in conformance with subparagraph (1)(a) within one year of the introduction of a new water source for a community water system. More frequent monitoring shall be conducted when ordered by the Director in the event of possible contamination or when changes in the distribution system or treatment process occur which may increase the concentration of radioactivity in drinking water.3. A community water system using two or more sources having different concentrations of radioactivity shall monitor each source of water, in addition to water from a free flowing drinking water tap, when ordered by the Director.4. Monitoring for compliance with Rule 391-3-5-.18(5) after the initial period need not include Radium-228 except when required by the Director provided, that the average annual concentration of Radium-228 has been assayed at least once using the quarterly sampling procedure required by subparagraph (l)(a).5. Suppliers of water shall, as ordered by the Director, conduct annual monitoring of any community water system in which the Radium-228 concentration exceeds 3 pCi/L.(d) If the MCL for gross alpha particle activity or total radium as set forth in Rule 391-3-5-.18(5) is exceeded, the supplier of a community water system shall give notice to the Division pursuant to Rule 391-3-5-.30 and notify the public pursuant to Rule 391-3-5-.32. Monitoring at quarterly intervals shall be continued until the annual average concentration no longer exceeds the maximum contaminant level or until a monitoring schedule as a condition to a permit, variance, exemption or enforcement action shall become effective.(e) The Division may require more frequent monitoring than specified in this section, or may require confirmation samples at its discretion. The results of the initial and confirmation samples will be averaged for use in compliance determinations.(f) Compliance with Rule 391-3-5-.18(5) will be determined based on the analytical result(s) obtained at each sampling point. If one sampling point is in violation of an MCL, the system is in violation of the MCL. Systems must include all samples taken and analyzed under the provisions of this section in determining compliance, even if that number is greater than the minimum required.(2)Monitoring Requirements for Man-made Radioactivity in Community Water Systems.(a) Within two years following June 24, 1977 systems using surface water sources and serving more than 100,000 persons and such other community water systems as are designated by the Division shall be monitored for compliance with Rule 391-3-5-.18(5) by analysis of a composite of four consecutive quarterly samples or analysis of four quarterly samples. Compliance with Rule 391-3-5-.18(5) may be assumed without further analysis if the average annual concentrations of tritium and strontium-90 are less than those listed in Table A, provided, that in no case shall the sum of their annual dose equivalents to bone marrow exceed 4 milligrams per year. 1. If the gross beta particle activity exceeds 50 pCi/L, an analysis of the sample must be performed to identify the major radioactive constituents present and the appropriate organ and total body doses shall be calculated to determine compliance with Rule 391-3-5-.18(5).2. Suppliers of water shall conduct additional monitoring, as ordered by the Director, to determine the concentration of man-made radioactivity in principal watersheds designated by the Division.3. At the discretion of the Director suppliers of water utilizing only ground waters may be required to monitor for man-made radioactivity.(b) After the initial analysis required by subparagraph (2)(a) suppliers of water shall monitor at least every four years following the procedure given in subparagraph (2)(a).(c) Within two years of June 24, 1977 the supplier of any community water system designated by the Division as utilizing waters contaminated by effluents from nuclear facilities shall initiate quarterly monitoring for gross beta particle and iodine-131 radioactivity and annual monitoring for strontium-90 and tritium. 1. Quarterly monitoring for gross beta particle activity shall be based on the analysis of monthly samples or the analysis of a composite of three monthly samples. The former is recommended. If the gross beta particle activity in a sample exceeds 15 pCi/L, the same or an equivalent sample shall be analyzed for strontium-89 and cesium-134. If the gross beta particle activity exceeds 50 pCi/L, an analysis of the sample must be performed to identify the major radioactive constituents present and the appropriate organ and total body doses shall be calculated to determine compliance with Rule 391-3-5-.18(5).2. For iodine-131, a composite of five consecutive daily samples shall be analyzed once each quarter. As ordered by the Director, more frequent monitoring shall be conducted when iodine-131 is identified in the drinking water.3. Annual monitoring for strontium-90 and tritium shall be conducted by means of the analysis of a composite of four consecutive quarterly samples or analysis of four quarterly samples. The latter procedure is recommended.4. The Division may allow the substitution of environmental surveillance data taken in conjunction with a nuclear facility for direct monitoring of man-made radioactivity by the supplier of water where the Division determines such data is applicable to a particular community water system.(d) If the average annual maximum contaminant level for manmade radioactivity set forth in Rule 391-3-5-.18(5) is exceeded, the operator of a community water system shall give notice to the Division pursuant to Rule 391-3-5-.30 and to the public as required by Rule 391-3-5-.32. Monitoring at monthly intervals shall be continued until the concentration no longer exceeds the maximum contaminant level or until a monitoring schedule as a condition to a permit, variance, exemption or enforcement action shall become effective.(3)Sample Collection and Analysis. Upon written direction of the Director, the supplier shall collect and submit drinking water samples for analysis in accordance with the schedule furnished. The Division shall have the discretion to delete results of obvious sampling or analytic errors. CWSs must conduct more frequent monitoring when ordered by the State in the event of possible contamination or when changes in the distribution system or treatment processes occur which may increase the concentration of radioactivity in finished water.(4)Analytical Methods. Analytical methods for measurements, detection limits and determining compliance with maximum contaminant levels listed in Rule 391-3-5-.18 for radioactivity shall be in accordance with 40 CFR, Part 141.25.(5)Monitoring Requirements Effective December 7, 2003. All existing community water systems (CWSs) must conduct initial monitoring to determine compliance with this rule between December 7, 2003 and December 31, 2007. CWSs must sample each entry point to the distribution system for four consecutive quarters. All existing CWSs using ground water, surface water or systems using both ground and surface water systems must sample at every entry point to the distribution system that is representative of all sources being used under normal operating conditions. The system must take each sample at the same sampling point unless conditions make another sampling point more representative of each source or the Division has designated a distribution system location, in accordance with 40 CFR § 141.26(a)(2)(ii)(C).(6)New Sources. All new CWSs or CWSs that use a new source of water shall begin to conduct initial monitoring within the first quarter after initiating use of the source.(7)Initial Monitoring Waiver. For gross alpha particle activity, uranium, radium-226, and radium-228 monitoring, the Division may waive the final two quarters of initial monitoring for a sampling point if the results of the samples from the previous two quarters are below the detection limit.(8)Initial Monitoring Above MCL. If the average of the initial monitoring results for a sampling point is above the MCL, the system must collect and analyze quarterly samples at the sampling point until the system has results from four consecutive quarters that are at or below the MCL, unless the system enters into another schedule as part of a formal compliance agreement with the Division.(9)Reduced Monitoring. The Division may allow community water systems to reduce the future frequency of monitoring from once every three years to once every six or nine years at each sampling point, based on the following criteria: (a) If the average of the initial monitoring results for each contaminant (i.e., gross alpha particle activity, uranium, radium-226, or radium-228) is below the detection limit specified in Table B, in Sec. 141.25(c)(1), the system must collect and analyze for that contaminant using at least one sample at the sampling point every nine years.(b) For gross alpha particle activity and uranium, if the average of the initial monitoring results for each contaminant is at or above the detection limit but at or below half (1/2) the MCL, the system must collect and analyze for that contaminant using at least one sample at that sampling point every six years. For combined radium-226 and radium-228, the analytical results must be combined. If the average of the combined initial monitoring results for radium-226 and radium-228 is at or above the detection limit but at or below half (1/2) the MCL, the system must collect and analyze for that contaminant using at least one sample at that sampling point every six years.(c) For gross alpha particle activity and uranium, if the average of the initial monitoring results for each contaminant is above half (1/2) the MCL but at or below the MCL, the system must collect and analyze at least one sample at that sampling point every three years. For combined radium-226 and radium-228, the analytical results must be combined. If the average of the combined initial monitoring results for radium-226 and radium-228 is above half (1/2) the MCL but at or below the MCL, the system must collect and analyze at least one sample at that sampling point every three years.(d) Systems must use the samples collected during the reduced monitoring period to determine the monitoring frequency for subsequent monitoring periods, (e.g., if a system's sampling point is on a nine year monitoring period, and the sample result is above half (1/2) MCL, then the next monitoring period for that sampling point is three years).(e) If a system has a monitoring result that exceeds the MCL while on reduced monitoring, the system must collect and analyze quarterly samples at that sampling point until the system has results from four consecutive quarters that are below the MCL, unless the system enters into another schedule as part of a formal compliance agreement with the Division.(10)Compositing. To fulfill quarterly monitoring requirements for gross alpha particle activity, radium-226, radium-228, or uranium, a system may composite up to four consecutive quarterly samples from a single entry point if analysis is done within a year of the first sample. The Division will treat analytical results from the composited as the average analytical result to determine compliance with the MCLs and the future monitoring frequency. If the analytical result from the composited sample is greater than half (1/2) MCL, the Division may direct the system to take additional quarterly samples before allowing the system to sample under a reduced monitoring schedule.(11)Gross Alpha Particle Activity. A gross alpha particle activity measurement may be substituted for the required radium-226 measurement provided that the measured gross alpha particle activity does not exceed 5 pCi/L. A gross alpha particle activity measurement may be substituted for the required uranium measurement provided that the measured gross alpha particle activity does not exceed 15 pCi/L. The gross alpha measurement shall have a confidence interval of 95% (1.65 [LOWER CASE SIGMA], where [LOWER CASE SIGMA] is the standard deviation of the net counting rate of the sample) for radium-226 and uranium. When a system uses a gross alpha particle activity measurement in lieu of a radium-226 and/or uranium measurement, the gross alpha particle activity analytical result will be used to determine the future monitoring frequency for radium-226 and/or uranium. If the gross alpha particle activity result is less than detection, the detection limit will be used to determine compliance and the future monitoring frequency.(12)Monitoring and Compliance Requirements for Beta Particle and Photon Radioactivity. To determine compliance with the maximum contaminant levels in 40 CFR Sec. 141.66(d) for beta particle and photon radioactivity, a system must monitor at a frequency as follows: (a) Community water systems (both surface and ground water) designated by the Division as vulnerable must sample for beta particle and photon radioactivity. Systems must collect quarterly samples for both beta emitters and annual samples for tritium and strontium-90 at each entry point to the distribution system (hereafter called a sampling point), beginning within one quarter after being notified by the Division. Systems already designated by the Division must continue to sample until the Division reviews and either reaffirms or removes the designation. 1. If the gross beta particle activity minus the naturally occurring potassium-40 beta particle activity at a sampling point has a running annual average (computed quarterly) less than or equal to 50 pCi/L (screening level), the Division may reduce the frequency of monitoring at that sampling point to once every 3 years. Systems must collect all samples required in paragraph 12(a) during the reduced monitoring period.2. For systems in the vicinity of a nuclear facility, the Division may allow the CWS to utilize environmental surveillance data collected by the nuclear facility in lieu of monitoring at the system's entry point(s), where the Division determines if such data is applicable to a particular water system. In the event that there is a release from a nuclear facility, systems which are using surveillance data must begin monitoring at the community water system's entry point(s) in accordance with paragraph 12(a) of this rule.(b) Community water systems (both surface and ground water) designated by the Division as utilizing waters contaminated by effluents from nuclear facilities must sample for beta particle and photon radioactivity. Systems must collect quarterly samples for beta emitters and iodine-131 and annual samples for tritium and strontium-90 at each entry point to the distribution system (hereafter called a sampling point), beginning within one quarter after being notified by the Division. Systems already designated by the Division as systems using waters contaminated by effluents from nuclear facilities must continue to sample until the Division reviews and either reaffirms or removes the designation.1. Quarterly monitoring for gross beta particle activity shall be based on the analysis of monthly samples or the analysis of a composite of three monthly samples. The former is recommended.2. For iodine-131, a composite of five consecutive daily samples shall be analyzed once each quarter. As ordered by the Division, more frequent monitoring shall be conducted when iodine-131 is identified in the finished water.3. Annual monitoring for strontium-90 and tritium shall be conducted by means of the analysis of a composite of four consecutive quarterly samples or analysis of four quarterly samples. The latter procedure is recommended.4. If the gross beta particle activity beta minus the naturally occurring potassium-40 beta particle activity at a sampling point has a running annual average (computed quarterly) less than or equal to 15 pCi/L, the Division may reduce the frequency of monitoring at that sampling point to every 3 years. Systems must collect the same type of samples required in paragraph 12(b) during the reduced monitoring period.5. For systems in the vicinity of a nuclear facility, the Division may allow the CWS to utilize environmental surveillance data collected by the nuclear facility in lieu of monitoring at the system's entry point(s), where the Division determines if such data is applicable to a particular water system. In the event that there is a release from a nuclear facility, systems which are using surveillance data must begin monitoring at the community water system's entry point(s) in accordance with paragraph 12(b).(c) Community water systems designated by the Division to monitor for beta particle activity and photon radioactivity cannot apply to the Division for a waiver from the monitoring frequencies specified in paragraphs 12(a) or 12(b).(d) Community water systems may analyze for naturally occurring potassium-40 beta particle activity from the same or equivalent sample used for the gross beta particle activity analysis. Systems are allowed to subtract the potassium-40 beta particle activity value from the total gross beta particle activity value to determine if the screening level is exceeded. The potassium-40 beta particle activity must be calculated by multiplying elemental potassium concentrations (in mg/L) by a factor of 0.82.(e) If the gross beta particle activity minus the naturally occurring potassium-40 beta particle activity exceeds the screening level, an analysis of the sample must be performed to identify the major radioactive constituents present in the sample and the appropriate doses must be calculated and summed to determine compliance with 40 CFR Sec. 141.66(d)(1), using the formula in 40 CFR Sec. 141.66(d)(2). Doses must also be calculated and combined for measured levels of tritium and strontium to determine compliance.(13)Monthly Sampling. Systems must monitor monthly at the sampling point(s) which exceed the maximum contaminant level in 40 CFR Sec. 141.66(d) beginning the month after the exceedance occurs. Systems must continue monthly monitoring until the system has established, by a rolling average of 3 monthly samples, that the MCL is being met. Systems who establish that the MCL is being met must return to quarterly monitoring until they meet the requirements set forth in paragraphs (12)(a)(1) or 12(b)(4).(14)Running Annual Average. For systems monitoring more than once per year, compliance with the MCL is determined by a running annual average at each sampling point. If the average of any sampling point is greater than the MCL, then the system is out of compliance with the MCL.(15)Exceeding MCL. For systems monitoring more than once per year, if any sample result will cause the running average to exceed the MCL at any sample point, the system is out of compliance with the MCL immediately.(16)Running Annual Average Calculation. If a system does not collect all required samples when compliance is based on a running annual average of quarterly samples, compliance will be based on the running average of the samples collected.(17)Detection Limit and Running Annual Average Calculation. If a sample result is less than the detection limit, zero will be used to calculate the annual average, unless a gross alpha particle activity is being used in lieu of radium-226 and/or uranium. If the gross alpha particle activity result is less than detection, half (1/2) the detection limit will be used to calculate the annual average.(18)MCLGs. The Maximum Contaminant Level Goal (MCLG) for Combined radium-226 and radium-228, Gross alpha particle activity, Beta particle and photon radioactivity, and uranium is zero.(19)MCLs. The Maximum Contaminant Level (MCL) for radioactive particles is as follows: (a) MCL for combined radium-226 and radium-228. The maximum contaminant level for combined radium-226 and radium-228 is 5 pCi/L. The combined radium-226 and radium-228 value is determined by the addition of the results of the analysis for radium-226 and the analysis for radium-228.(b) MCL for gross alpha particle activity (excluding radon and uranium). The maximum contaminant level for gross alpha particle activity (including radium-226 but excluding radon and uranium) is 15 pCi/L.(c) MCL for beta particle and photon radioactivity. The average annual concentration of beta particle and photon radioactivity from man-made radionuclides in drinking water must not produce an annual dose equivalent to the total body or any internal organ greater than four millirem per year (4 mrem/yr).(d) MCL for uranium. The maximum contaminant level for uranium is 30 µg/L.(20)Best available technology.40 CFR Parts 141.66(g) and 141.66(h) are incorporated by reference.Ga. Comp. R. & Regs. R. 391-3-5-.27
O.C.G.A. § 12-5-170 et seq.
Original Rule entitled "Secondary Maximum Contaminant Levels for Drinking Water" adopted. F. July 5, 1977; eff. July 26, 1977, as specified by Rule 391-3-5-.47.Repealed: New Rule of the same title adopted. F. July 15, 1983; eff. August 4, 1983.Repealed: New Rule entitled "Monitoring Frequency and Analytical Methods for Radioactivity in Community Water Systems" adopted. F. May 12, 1989; eff. June 1, 1989.Amended: F. Dec. 4, 1990; eff. Dec. 24, 1990.Amended: F. Sept. 26, 1997; eff. Oct. 16, 1997.Amended: F. June 8, 2001; eff. June 28, 2001.Amended: F. Dec. 10, 2002; eff. Dec. 30, 2002.Amended: F. Jan. 8, 2014; eff. Jan. 28, 2014.Amended: New title "Monitoring Frequency and Analytical Methods for Radioactivity in Community Water Systems." F. Feb. 29, 2016; eff. Mar. 20, 2016.Amended: F. Apr. 22, 2021; eff. May 12, 2021.