401 KAR 8:162. Enhanced filtration and disinfection for small systems serving less than 10,000 people.

401 KAR 8:162. Enhanced filtration and disinfection for small systems serving less than 10,000 people.

RELATES TO: KRS 224.10-100, 224.10-110, 40 C.F.R. 141.74, 141.500-141.571

STATUTORY AUTHORITY: KRS 224.10-100(30), 224.10-110(2), 40 C.F.R. 141.74, 141.500-141.571, 42 U.S.C. Chapter 6A Subchapter XII

NECESSITY, FUNCTION, AND CONFORMITY: KRS 224.10-100(30) and 224.10-110(2) authorize the Secretary of the Environmental and Public Protection Cabinet to promulgate administrative regulations for the regulation and control of the purification of water for public and semipublic use. This administrative regulation establishes requirements for filtration and disinfection for a public water system that serves fewer than 10,000 people.

Section 1. Applicability. (1)(a) This administrative regulation shall be considered a national primary drinking water regulation for the surface water treatment rules of enhanced filtration and disinfection for small systems.

(b) This administrative regulation establishes requirements for filtration and disinfection that are in addition to the criteria in 401 KAR 8:150 under which filtration and disinfection are required for a public water system that uses surface water or groundwater under the direct influence of surface water.

(2) This administrative regulation shall apply to a public water system that serves fewer than 10,000 persons and that uses as its source surface water or groundwater under the direct influence of surface water.

Section 2. General Provisions. (1)(a) This administrative regulation establishes or extends treatment technique requirements instead of maximum contaminant levels for the following contaminants:

1. Giardia lamblia;

2. Viruses;

3. Heterotrophic plate count bacteria;

4. Legionella;

5. Cryptosporidium; and

6. Turbidity.

(b) The treatment technique requirements shall consist of installing and properly operating water treatment processes that reliably achieve:

1. At least ninety-nine (99) percent (2-log) removal of Cryptosporidium between a point where the raw water is not subject to recontamination by surface water runoff and a point downstream before or at the first customer; and

2. Compliance with the profiling and benchmark requirements in Sections 3 and 4 of this administrative regulation.

(2) General requirements. A public water system that is subject to this administrative regulation shall comply with the following five (5) requirements, as applicable to the system:

(a) A community or nontransient noncommunity water system shall develop a disinfection profile as described in Section 3 of this administrative regulation;

(b) A water system that is considering making a significant change to its disinfection practices shall develop a disinfection benchmark and consult with the cabinet for approval of the change as described in Section 4 of this administrative regulation;

(d) A system that uses conventional or direct filtration shall comply with the individual filter turbidity requirements of Section 6 of this administrative regulation; and

(e) A system shall comply with the reporting and recordkeeping requirements described in Section 7 of this administrative regulation.

Section 3. Disinfection Profile. (1)(a) Determination of systems required to profile. A community or nontransient noncommunity water system shall develop a disinfection profile unless pursuant to subsection (2) of this section, a system profile is unnecessary.

(b) The disinfection profile shall contain a graphical representation of the system’s level of Giardia lamblia or virus inactiviation measured during the course of a year.

(c) The cabinet may approve the use of a more representative data set using criteria established in 40 C.F.R. 141.530, January 14, 2002, for disinfection profiling than the data set required in subsections (3) to (7) of this section.

(2) Only the following information shall be used to determine if a system’s profiling shall not be required:

(a) The system’s total trihalomethane level is below 0.064 mg/L, and the haloacetic acid level is below 0.048 mg/L; and

(b) The data used to determine the levels shall have been collected after January 1, 1998, during the month with the warmest water temperature, and at the point of maximum residence time in the distribution system.

(3) Developing profile. A disinfection profile shall consist of three (3) steps specified in paragraphs (a) to (c) of this subsection:

(a) 1. The system shall collect the data specified in subsection (4) of this section over the course of twelve (12) months.

2. a. A system that serves between 500 and 9,999 persons shall have begun to collect the data not later than July 1, 2003.

b. A system that serves fewer than 500 persons shall have begun to collect the data not later than July 1, 2004.

(b) The system shall use the data collected to calculate weekly log inactivations, as discussed in subsections (5) and (6) of this section; and

(c) The system shall use the weekly log inactivations to develop a disinfection profile as specified in subsection (7) of this section.

(4) Data required. The following parameters shall be monitored to determine the total log inactivation using the analytical methods in 40 C.F.R. 141.74(a), September 18, 1998, once per week on the same calendar day over twelve (12) consecutive months:

(a) The temperature of the disinfected water at each residual disinfectant concentration sampling point during peak hourly flow;

(b) If chlorine is used, the pH of the disinfected water at each sampling point during peak hourly flow;

(d) The residual disinfectant concentration, or "C", of the water before or at the first customer and before each additional point of disinfection during peak hourly flow.

(5) Calculation of inactivation ratio and log inactivation.

(a) The total inactivation ratio shall be calculated as follows:

1. If the system uses only one (1) point of disinfectant application:

a. One (1) inactivation ratio before or at the first customer during peak hourly flow as follows: CT_calc/CT_99.9; or

b. Successive ratio values, CT_calc/CT_99.9, representing sequential inactivation ratios between the point of disinfectant application and a point before or at the first customer during peak hourly flow. Under this alternative, the system shall calculate the total inactivation ratio by determining CT_calc/CT_99.9 for each sequence and then adding the CT_calc/CT_99.9 values together to determine their summation, or ∑(CT_calc/CT_99.9).

2. If a system uses more than one (1) point of disinfectant application before the first customer, the system shall determine the CT value of each disinfection segment immediately before the next point of disinfectant application, or for the final segment, before or at the first customer, during peak hourly flow. The CT_calc/CT_99.9 value of each segment and ∑(CT_calc/CT_99.9) shall be calculated using the method in subparagraph 1b of this paragraph.

(b) The log inactivation of Giardia lamblia shall be determined by multiplying the total inactivation ratio by three and zero-tenths (3.0).

(6) A system that uses chloramines, ozone, or chlorine dioxide for primary disinfection shall calculate the logs of inactivation for viruses and shall develop an additional disinfection profile using a method specified in 401 KAR 8:150.

(7) Disinfection profile.

(a)1. A system shall calculate the inactivation ratio every week for fifty-two (52) consecutive weeks.

2. Each log inactivation ratio shall serve as a data point in the disinfection profile.

3. The system shall retain the disinfection profile data in a graphic form, such as a spreadsheet.

(b) The disinfection profile shall be available for review by the cabinet as part of a sanitary survey pursuant to 401 KAR 8:022.

(c) If the system is considering changes to disinfection practices, these data shall be used to calculate a benchmark pursuant to Section 4 of this administrative regulation.

Section 4. Disinfection Benchmark. A public water system required to perform a disinfection profile under Section 3 of this administrative regulation shall develop a disinfection benchmark before making a significant change in the distribution practice and shall consult with the cabinet for its approval before initiating any change, according to the procedures in this section.

(1) A significant disinfectant practice change shall include:

(a) A change to the point of disinfection;

(b) A change to the disinfectant used in the treatment plant;

(d) Another modification identified pursuant to 40 C.F.R. 141.541, January 14, 2002.

(2)(a) A system that is considering a significant change to the disinfection practice pursuant to subsection (1) of this section shall submit the information required in subsection (3) of this section and the disinfection benchmark calculated according to subsections (4) and (5) of this section to the cabinet for its approval.

(b) Criteria for cabinet approval shall be in accordance with 40 C.F.R. 141.542, January 14,2002.

(3) The following information shall be submitted to the cabinet as part of the consultation and approval process:

(a) A description of the proposed change;

(b) The disinfection profile for Giardia lamblia and viruses, if necessary, and the disinfection benchmark;

(d) Any other information pursuant to 40 C.F.R. 141.542, January 14, 2002, that is necessary for the cabinet to determine whether to approve the significant change.

(4) Calculation. The disinfection benchmark shall be calculated according to the following procedure:

(a) Using the data collected to develop the disinfection profile, determine the average Giardia lamblia inactivation for each calendar month by dividing the sum of all Giardia lamblia inactivations for that month by the number of values calculated for that month.

(b) Determine the lowest monthly average value out of the twelve (12) values. This lowest value shall be the disinfection benchmark.

(5)(a) A system that uses chloramine, ozone, or chlorine dioxide for primary disinfection shall calculate the disinfection benchmark from the data collected for viruses to develop the disinfection profile, in addition to the Giardia lamblia disinfection benchmark calculated under subsection (4) of this section.

(b) This viral benchmark shall be calculated in the same manner used to calculate the Giardia lamblia disinfection benchmark in subsection (4) of this section.

Section 5. Combined Filter Effluent Requirements. A public water system that uses filtration other than slow sand filtration or diatomaceous earth filtration shall meet the combined filter effluent turbidity requirements specified in subsections (1) to (3) of this section. A system that uses slow sand or diatomaceous earth filtration may meet the combined filter effluent turbidity limits of this administrative regulation but shall continue to meet the combined filter effluent turbidity limits in 401 KAR Chapter 8:150 Section 2(2) and (3).

(1) Turbidity treatment technique requirements:

(a) A system that uses conventional filtration or direct filtration shall meet the following two (2) combined filter effluent turbidity limits:

1. 0.3 NTU in ninety-five (95) percent of the readings each month. This shall be the 95th percentile reading; and

2. A maximum turbidity limit of one (1) NTU, which shall not be exceeded.

(b) A system that uses alternative filtration shall meet the two (2) turbidity limits, which are determined in accordance with 40 C.F.R. 141.552, January 14, 2002, based on the demonstration described in subsection (2) of this section, of:

1. A 95th percentile value, which shall not be more than one (1) NUT; and

2. A maximum turbidity limit, which shall not be more than five (5) NTU.

(c)1. The measurements for paragraphs (a) and (b) of this subsection shall be taken as described in 40 C.F.R. 141.74(a) and (c), September 18, 1998.

2. The system shall complete and submit monthly reports pursuant to Section 7 of this administrative regulation.

(2) Alternative filtration demonstration. A system that uses filtration other than slow sand filtration, diatomaceous earth filtration, conventional filtration, or direct filtration shall demonstrate to the cabinet, using criteria established in 40 C.F.R. 141.73(d), June 29, 2004, that the system’s filtration, in combination with disinfection treatment, consistently achieves:

(a) Ninety-nine (99) percent (2-log) removal of Cryptosporidium oocysts;

(b) Ninety-nine and nine-tenths (99.9) percent (3-log) removal or inactivation of Giardia lamblia cysts; and

(3) Lime softening. A system that practices lime softening may acidify representative combined filter effluent turbidity samples before analysis using a protocol specified by the "Long Term 1 Enhanced Surface Water Treatment Rule Turbidity Provisions: Technical Guidance Manual.

Section 6. Individual Filter Turbidity Requirements. (1) A system that uses as its source surface water or groundwater under the direct influence of surface water, that serves fewer than 10,000 persons, and that uses conventional filtration or direct filtration shall conduct continuous monitoring for turbidity at each individual filter in the system. The system shall:

(a) Conduct monitoring using a method approved in 40 C.F.R. 141.74(a), September 18, 1998;

(b) Calibrate the turbidimeter using procedures specified by the manufacturer;

(d) Complete and submit monthly reports according to Section 7(1) of this administrative regulation; and

(e) Maintain records according to Section 7 of this administrative regulation.

(2) Equipment failure.

(a) If there is a failure in the continuous turbidity monitoring equipment, the system shall conduct grab sampling every four (4) hours instead of continuous monitoring, until the turbidimeter is back on line.

(b) If the continuous monitoring is not resumed within fourteen (14) days, the system shall be in violation of this administrative regulation.

(3) Special provisions.

(a) If a system consists of two (2) or fewer filters, the system may conduct continuous monitoring of combined filter effluent turbidity instead of individual filter effluent turbidity monitoring.

(b) The continuous monitoring shall meet the requirements set forth in subsections (1)(a) to (d) and (2) of this section.

(4) Follow-up action.

(a) If the turbidity of an individual filter, or the turbidity of combined filter effluent for a system with two (2) filters that monitors the combined filter effluent instead of individual filters, exceeds one and zero-tenths (1.0) NTU in two (2) consecutive recordings fifteen (15) minutes apart, the system shall report to the cabinet by the tenth day of the following month. The report shall include:

1. The filter number;

2. The date of exceedance;

3. Turbidity values that exceeded one and zero-tenths (1.0) NTU; and

4. The cause of the exceedance, if known.

(b)1. If a system shall report to the cabinet:

a. For three (3) consecutive months, and the turbidity exceeds one and zero-tenths (1.0) NTU in two (2) consecutive recordings fifteen (15) minutes apart at the same filter, or combined filter effluent for a system with two (2) filters that monitors combined filter effluent instead of individual filters, the system shall conduct a self-assessment of each filter within fourteen (14) days of the date the filter exceeded one and zero-tenths (1.0) NTU in two (2) consecutive measurements for the third straight month, unless a comprehensive performance evaluation shall be performed pursuant to clause b of this subparagraph. A system with two (2) filters that monitors combined filter effluent instead of individual filters shall conduct a self-assessment on both filters. The self-assessment shall consist of at least the following:

(i) Assessment of filter performance;

(ii) Development of a filter profile;

(iii) Identification and prioritization of factors that limit filter performance;

(iv) Assessment of the applicability of corrections;

(v) Preparation of a filter self-assessment report;

(vi) The date the report was triggered; and

(vii) The date the report was completed.

b. For two (2) consecutive months and, the turbidity exceeded two and zero-tenths (2.0) NTU in two (2) consecutive recordings that were fifteen (15) minutes apart at the same filter, or combined filter effluent for a system with two (2) filters that monitors combined filter effluent instead of individual filters, the system shall arrange to have a comprehensive performance evaluation conducted by the cabinet or a third party approved by the cabinet, no later than sixty (60) days following the date the filter exceeded two and zero-tenths (2.0) NTU in two (2) consecutive measurements for the second straight month. Requirements for third party approval shall be in accordance with 40 C.F.R. 141.563(c), June 29, 2004.

(i) If a comprehensive performance evaluation has been completed by the cabinet or a third party approved by the cabinet within the twelve (12) previous months, or the system and cabinet are jointly participating in an ongoing comprehensive technical assistance project at the system, a new comprehensive performance evaluation shall not be required.

(ii) If conducted, a comprehensive performance evaluation shall be completed and submitted to the cabinet not later than 120 days after the day the filter exceeded two and zero-tenths (2.0) NTU in two (2) consecutive measurements for the second straight month.

(5) Lime softening.

(a) A system that practices lime softening may apply to the cabinet for alternative turbidity exceedance levels for the levels specified in the follow up actions required in subsection (4) of this section.

(b) The system shall demonstrate to the cabinet that higher turbidity levels are due only to lime carryover and are not due to degraded filter performance.

Section 7. Reporting and Recordkeeping. (1) A system shall report combined filter effluent information by the tenth day of the following month. This report shall include:

(a) Total number of filtered water turbidity measurements taken during the month;

(b) Number and percentage of filtered water turbidity measurements taken during the month that are less than or equal to the system’s required 95th percentile limit; and

(c) Date and value of any turbidity measurements taken during the month that exceed the maximum turbidity value for the filtration system.

(2) A system shall report individual filter effluent information by the tenth day of the following month. This report shall include:

(a) That the system has conducted individual filter turbidity monitoring;

(b) The filter number, corresponding date, and turbidity values that exceeded one and zero-tenths (1.0) NTU during the month, but only if two (2) consecutive measurements exceeded one and zero-tenths (1.0) NTU;

2. This information shall be submitted to the cabinet by the tenth day of the following month, or, if the self assessment was triggered only during the last four (4) days of the month, within fourteen (14) days after the self-assessment was triggered;

(d) If a comprehensive performance evaluation shall be required, the fact that the evaluation was required and the date that it was triggered; and

(e) A copy of the completed comprehensive performance evaluation within 120 days after the evaluation was triggered.

(3) Disinfection profiling. The following information shall have been submitted to the cabinet by July 1, 2003 for a system that serves 500 to 9999, or July 1, 2004 for a system that serves less than 500:

(a) The fact that the system has begun disinfection profiling; or

(b) If the system forgoes profiling, the results of optional monitoring that shows levels of total trihalomethanes less than 0.064 mg/L and levels of haloacetic acids less than 0.048 mg/L.

(4) Disinfection benchmarking. If the system is considering a significant change to its disinfection practice, the system shall submit to the cabinet:

(a) A description of the proposed change in disinfection;

(b) The system’s disinfection profile for Giardia lamblia and viruses if necessary;

(d) An analysis of how the proposed change will affect the current levels of disinfection.

(5) Recordkeeping. In addition to the recordkeeping requirements of 40 C.F.R. 141.75, January 16, 2001, the system shall maintain the following records for the indicated period.

(a) Results of individual filter monitoring: At least three (3) years; and

(b) Results of profile and benchmark data, including raw data and analyses: Permanently.

Section 8. Incorporation by Reference. (1) "Long Term 1 Enhanced Surface Water Treatment Rule Turbidity Provisions: Technical Guidance Manual", August 2004, as published by the U.S. Environmental Protection Agency, Washington, D.C. is incorporated by reference.

(2) This material may be inspected, copied, or obtained, subject to applicable copyright law, at Division of Water, 14 Reilly Road , Frankfort, Kentucky 40601, Monday through Friday, 8:00 a.m. to 4:30 p.m. or through www.water.ky.gov. (33 Ky.R. 1750; Am. 3631; eff. 6-13-2007.)