401 KAR 8:160. Enhanced filtration and disinfection for large systems serving at least 10,000 people.

401 KAR 8:160. Enhanced filtration and disinfection for large systems serving at least 10,000 people.

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

STATUTORY AUTHORITY: KRS 224.10-100(30), 224.10-110(2), 40 C.F.R. 141.74, 141.170-141.175, 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 at least 10,000 people.

Section 1. Applicability. (1) This administrative regulation shall be considered a national primary drinking water regulation.

(2) This administrative regulation establishes requirements for filtration and disinfection 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.

(3) This administrative regulation, this administrative regulation shall apply to a system that serves at least 10,000 people and uses 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) A system that uses surface water or groundwater under the direct influence of surface water and that serves at least 10,000 people shall provide treatment of its source water that complies with these treatment technique requirements in addition to those identified in 401 KAR 8:150.

(c) 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 Section 3 of this administrative regulation.

(2) A public water system subject to this administrative regulation shall be considered to be in compliance with subsection (1) of this section if it meets:

(a) The applicable filtration requirements in either Section 4 of this administrative regulation or 401 KAR 8:150, Section 2; and

(b) The disinfection requirements in Section 3 of this administrative regulation and 401 KAR 8:150, Section 1.

Section 3. Disinfection Profiling and Benchmarking. (1) Determination of systems required to profile. A public water system subject to this administrative regulation shall determine its total trihalomethane, or TTHM, annual average and its haloacetic acid five (5), or HAA5, annual average using the procedures in this subsection. The annual average shall be the arithmetic average of the quarterly averages of four (4) consecutive quarters of monitoring.

(a)

The HAA5 annual average shall be the annual average during the same period as is used for the TTHM annual average.

(b)1. A system that collected four (4) quarters of HAA5 occurrence data that meet the routine monitoring sample number and location requirements for TTHM in 401 KAR 8:510 may use those data to determine if the requirements of this section apply.

2. A system that has either a TTHM annual average of greater than or equal to 0.064 mg/L or an HAA5 annual average of greater than or equal to 0.048 mg/L shall comply with subsection (2) of this section.

(2) Disinfection profiling.

(a) A system that meets the criteria in subsection (1) of this section shall develop a disinfection profile of its disinfection practice for a period of up to three (3) years.

(b) The system shall monitor daily for twelve (12) consecutive months to determine the total logs of inactivation for each day of operation, based on the applicable CT_99.9 values in Tables 1.1 - 1.6, 2.1, and 3.1 of 40 C.F.R. 141.74(b), June 29, 2004, as applicable, through the entire treatment plant. April 1, 2000 shall be the beginning date for required monitoring.

1. As a minimum, the system with a single point of disinfectant application before the entrance to the distribution system shall conduct the monitoring in subparagraphs 3a to d of this paragraph.

2. A system with more than one (1) point of disinfectant application shall conduct the monitoring in subparagraphs 3a to d of this paragraph for each disinfection segment.

3. The system shall monitor the parameters necessary to determine the total inactivation ratio, using analytical methods in 40 C.F.R. 141.74(a), June 29, 2004, as follows:

a. The temperature of the disinfected water shall be measured once each day at each residual disinfectant concentration sampling point during peak hourly flow;

b. If the system uses chlorine, the pH of the disinfected water shall be measured once per day at each chlorine residual disinfectant concentration sampling point during peak hourly flow;

c. The disinfectant contact time, or T, shall be determined for each day during peak hourly flow; and

d. The residual disinfectant concentration, or C, of the water before or at the first customer and before each additional point of disinfection shall be measured each day during peak hourly flow.

(c)1. Instead of the monitoring conducted under the provisions of paragraph (b) of this subsection to develop the disinfection profile, the system may elect to meet the requirements of subparagraph 2a of this paragraph.

2. In addition to the monitoring conducted under the provisions of paragraph (b) of this subsection to develop the disinfection profile, the system may elect to meet the requirement of clause b of this subparagraph.

a.(i) A public water system that has three (3) years of existing operational data may submit those data, a profile generated using those data, and a request that the cabinet approve use of those data instead of monitoring under the provisions of paragraph (b) of this subsection not later than March 31, 2000.

(ii) The cabinet shall determine if these operational data are substantially equivalent to data collected under the provisions of paragraph (b) of this subsection.

(iii) These data shall also be representative of Giardia lamblia inactivation through the entire treatment plant and not just of certain treatment segments.

(iv) The system shall continue to conduct monitoring under the provisions of paragraph (b) of this subsection until receipt of written approval from the cabinet.

b.(i) In addition to the disinfection profile generated under paragraph (b) of this subsection, a public water system that has existing operational data may use those data to develop a disinfection profile for additional years.

(ii) The system may use the additional yearly disinfection profiles to develop a benchmark under the provisions of subsection (3) of this section.

(iii) In accordance with 40 C.F.R. 141.72(b)(3)(ii), January 16, 2001, the cabinet shall determine if these operational data are substantially equivalent to data collected under the provisions of paragraph (b) of this subsection. These data shall also be representative of inactivation through the entire treatment plant and not just of certain treatment segments.

(d) The system shall calculate the total inactivation ratio as follows:

1. If the system uses only one (1) point of disinfectant application, the system shall determine the total inactivation ratio for the disinfection segment based on either of the following methods:

a. Determine one (1) inactivation ratio, CT_calc/CT_99.9, before or at the first customer during peak hourly flow; or

b.(i) Determine 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.

(ii) 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 å(CT_calc/CT_99.9).

2.a. If the 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.

b. The CT_calc/CT_99.9 value of each segment and å(CT_calc/CT_99.9) shall be calculated using the method in subparagraph 1 of this paragraph.

3. The system shall determine the total logs of inactivation by multiplying the value calculated in subparagraph 1 or 2 of this paragraph by three and zero-tenths (3.0).

(e) A system that uses either chloramines or ozone for primary disinfection shall also calculate the logs of inactivation for viruses using a method pursuant to 40 C.F.R. 141.172(b)(5), January 16, 2001.

(f) The system shall retain disinfection profile data in graphic form, as a spreadsheet, or in some other format in accordance with 40 C.F.R. 141.172(b)(b), January 16, 2001, for review as part of a sanitary survey conducted by the cabinet.

(3) Disinfection benchmarking.

(a) A system required to develop a disinfection profile under the provisions of subsections (1) and (2) of this section and that decides to make a significant change to its disinfection practice shall submit the proposed change to the cabinet for its approval in accordance with conditions in 40 C.F.R. 141.172(c), January 16, 2001, before initiating any change. A significant change to disinfection practice shall be:

1. A change to the point of disinfection;

2. A change to the disinfectant used in the treatment plant;

3. A change to the disinfection process; and

4. Any other modification as provided by 40 C.F.R. 141.172(c)(iv), January 16, 2005.

(b) A system that is modifying its disinfection practice shall calculate its disinfection benchmark using the following procedure:

1.a. For each year of profiling data collected and calculated under subsection (2) of this section, the system shall determine the lowest average monthly Giardia lamblia inactivation in each year of profiling data.

b. The system shall determine the average Giardia lamblia inactivation for each calendar month for each year of profiling data by dividing the sum of daily Giardia lamblia of inactivation by the number of values calculated for that month; and

2. The disinfection benchmark shall be the lowest monthly average value for a system with one (1) year of profiling data or the average of lowest monthly average values for a system with more than one (1) year of profiling data, of the monthly logs of Giardia lamblia inactivation in each year of profiling data.

(c) A system that uses either chloramines or ozone for primary disinfection shall also calculate the disinfection benchmark for viruses using a method in accordance with 40 C.F.R. 141.172(b)(5), January 16, 2001.

(d) The system shall submit the following information to the cabinet as part of the approval process:

1. A description of the proposed change;

2. The disinfection profile for Giardia lamblia and viruses, if necessary under subsection (2) of this section, and benchmark as required by paragraph (b) of this subsection; and

3. An analysis of how the proposed change will affect the current levels of disinfection.

Section 4. Filtration. A public water system subject to the requirements of this administrative regulation shall provide treatment consisting of both disinfection, as specified in 401 KAR 8:150, Section 1, and filtration treatment that complies with the requirements of subsections (1) and (2) of this section or 401 KAR 8:150, Section 2(2) or (3).

(1) Conventional filtration treatment or direct filtration.

(a) For a system using conventional filtration or direct filtration, the turbidity level or representative samples of a system's filtered water shall be less than or equal to three-tenths (0.3) NTU in at least ninety-five (95) percent of the measurements taken each month, measured as specified in 401 KAR 8:150, Section 3.

(b) The turbidity level of representative samples of a system's filtered water shall not exceed one (1) NTU, measured as specified in 401 KAR 8:150, Section 3.

(c) A system that uses lime softening may acidify representative samples before analysis using a protocol approved by the cabinet pursuant to 40 C.F.R. 141.173(a)(3), January 16, 2001.

(2) Filtration technologies other than conventional filtration treatment, direct filtration, slow sand filtration, or diatomaceous earth filtration.

(a) A public water system may use a filtration technology not listed in subsection (1) of this section or in 401 KAR 8:150, Section 2(2) or (3), if it demonstrates to the cabinet, using a pilot plant study or other means in accordance with 40 C.F.R. 141.173(b), January 16, 2001, that the alternative filtration technology, in combination with disinfection treatment that meets the requirements of 401 KAR 8:150, Section 1, consistently achieves ninety-nine and nine-tenths (99.9) percent (3-log) removal or inactivation of Giardia lamblia cysts and 99.99 percent (4-log) removal or inactivation of viruses, and ninety-nine (99) percent (2-log) removal of Cryptosporidium oocysts, and the cabinet approves the use of the filtration technology in accordance with conditions listed in 40 C.F.R. 141.173(b), January 16, 2001.

(b) For an approval, the cabinet shall set turbidity performance requirements as listed in 40 C.F.R. 141.173(b), January 16, 2001, that the system shall meet at least ninety-five (95) percent of the time and that the system shall not exceed at a level that consistently achieves ninety-nine and nine-tenths (99.9) percent removal or inactivation of Giardia lamblia cysts, 99.99 percent removal or inactivation of viruses, and ninety-nine (99) percent removal of Cryptosporidium oocysts.

Section 5. Filtration Sampling Requirements. (1) Monitoring requirements for a system using filtration treatment.

(a) In addition to monitoring required by 401 KAR 8:150, Section 3, a public water system subject to the requirements of this administrative regulation that provides conventional filtration treatment or direct filtration shall conduct continuous monitoring of turbidity for each individual filter using a method approved in 40 C.F.R. 141.74(a), January 29, 2004, and shall calibrate a turbidimeter using the procedure specified by the manufacturer.

(b) A system shall record the results of individual filter monitoring every fifteen (15) minutes.

(2)(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 repaired and back on-line.

(b) A system shall have a maximum of five (5) working days after failure to repair the equipment.

Section 6. Reporting and Recordkeeping Requirements. In addition to the reporting and recordkeeping requirements in 401 KAR 8:020, Section 2(7), a public water system subject to the requirements of this administrative regulation that provides conventional filtration treatment or direct filtration shall report monthly to the cabinet the information required in this section. In addition to the reporting and record keeping requirements in 401 KAR 8:020, Section 2(7), a public water system subject to the requirements of this administrative regulation that provides filtration approved under Section 4(2) of this administrative regulation shall report monthly to the cabinet the information specified in subsection (1) of this section. The reporting in subsection (1) of this section shall be required instead of the reporting specified in 401 KAR 8:020, Section 2(7)(a)1.

(1) Turbidity measurements as required by Section 4 of this administrative regulation shall be reported within ten (10) days after the end of each month the system serves water to the public. The following information shall be reported:

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

(b) The number and percentage of filtered water turbidity measurements taken during the month that are less than or equal to the turbidity limits specified in Section 4(1) or (2) of this administrative regulation; and

(c) The date and value of a turbidity measurement taken during the month that exceeds one (1) NTU for a system using conventional filtration treatment or direct filtration, or that exceeds the maximum level under Section 4(2) of this administrative regulation.

(2)(a) A system shall maintain the results of individual filter monitoring taken under Section 5 of this administrative regulation for at least three (3) years.

(b) A system shall report that it has conducted individual filter turbidity monitoring under Section 5 of this administrative regulation within ten (10) days after the end of each month the system serves water to the public.

(c) A system shall report individual filter turbidity measurement results taken under Section 5 of this administrative regulation within ten (10) days after the end of each month the system serves water to the public only if measurements demonstrate one (1) or more of the conditions in paragraphs (d)1 to (g) of this subsection.

(d) A system that uses lime softening may apply to the cabinet for an alternative exceedance level for the level specified in subparagraphs 1 to 4 of this paragraph if a higher turbidity level in an individual filter is due to lime carryover only and is not due to degraded filter performance.

1. For an individual filter that has a measured turbidity level of greater than one and zero-tenths (1.0) NTU in two (2) consecutive measurements taken fifteen (15) minutes apart, the system shall report the filter number, the turbidity measurement, and the date on which the exceedance occurred.

2. In addition, the system shall either:

a. Produce a filter profile for the filter within seven (7) days of the exceedance, if the system is not able to identify an obvious reason for the abnormal filter performance, and report that the profile has been produced; or

b. Report the obvious reason for the exceedance.

(e)1. For an individual filter that has a measured turbidity level of greater than five-tenths (0.5) NTU in two (2) consecutive measurements taken fifteen (15) minutes apart at the end of the first four (4) hours of continuous filter operation after the filter has been backwashed or otherwise taken offline, the system shall report the filter number, the turbidity, and the date on which the exceedance occurred.

2. In addition, the system shall either:

b. Report the obvious reason for the exceedance.

(f)1. For an individual filter that has a measured turbidity level of greater than one and zero-tenths (1.0) NTU in two (2) consecutive measurements taken fifteen (15) minutes apart during each of three (3) consecutive months, the system shall report the filter number, the turbidity, and the date on which the exceedance occurred.

2.a. In addition, the system shall conduct a self-assessment of the filter within fourteen (14) days of the exceedance and report that the self-assessment was conducted.

b. The self-assessment shall consist of at least the following components:

(i) Assessment of filter performance;

(ii) Development of a filter profile;

(iii) Identification and prioritization of factors limiting filter performance;

(iv) Assessment of the applicability of corrections; and

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

(g)1. For an individual filter that has a measured turbidity level of greater than two and zero-tenths (2.0) NTU in two (2) consecutive measurements taken fifteen (15) minutes apart in each of two (2) consecutive months, the system shall report the filter number, the turbidity measurement, and the date on which the exceedance occurred.

2.a. In addition, the system shall arrange for the cabinet or a third party approved by the cabinet in accordance with criteria listed in 40 C.F.R. 141.175(b)(4), January 16, 2001, to conduct a comprehensive performance evaluation pursuant to Section 7 of this administrative regulation not later than thirty (30) days after the exceedance.

b. The evaluation shall be completed and submitted to the cabinet not later than ninety (90) days after the exceedance.

(3) Additional reporting requirements.

(a) If the turbidity exceeds one (1) NTU in representative samples of filtered water in a system using conventional treatment or direct filtration, the system shall notify the cabinet as soon as possible, but not later than the end of the next business day.

(b) If the turbidity in representative samples of filtered water exceed the maximum level under Section 4(2) of this administrative regulation for filtration technologies other than conventional filtration treatment, direct filtration, slow sand filtration, or diatomaceous earth filtration, the system shall notify the cabinet as soon as possible, but not later than the end of the next business day.

Section 7. Comprehensive Performance Evaluation. (1) If notified by a system pursuant to Section 6(2)(g) of this administrative regulation, the cabinet or third party approved by the cabinet shall conduct a comprehensive performance evaluation to:

(a) Identify factors that may be adversely impacting a plant's capability to achieve compliance; and

(b) Emphasize an approach that a system may be able to implement without significant capital improvements.

(2) The comprehensive performance evaluation shall consist of at least the following:

(a) Assessment of plant performance;

(b) Evaluation of major unit processes;

(d) Assessment of the applicability of comprehensive technical assistance; and

(e) The final report of the results of the evaluation. (27 Ky.R. 1676; Am. 2758; eff. 4-9-2001; 33 Ky.R. 1666; 2998; 3628; eff. 6-13-07.)