Ala. Admin. Code r. 335-7-2-.13
Current through Register Vol. 43, No. 1, October 31, 2024
Section 335-7-2-.13 - Distribution System EvaluationThis rule establishes monitoring and other requirements for identifying compliance monitoring locations for use under rule 335-7-2-.12.
(a) This rule applies to: 1. Community water systems that use a primary or residual disinfectant other than ultraviolet light (UV) or deliver water that has been chemically treated with a primary or residual disinfectant;2. Nontransient noncommunity water systems that serve at least 10,000 people and use a primary or residual disinfectant other than UV or deliver water that has been chemically treated by a primary or residual disinfectant.(b) Systems must use a Distribution System Evaluation (DSE) to determine locations with high TTHM and HAA5 concentrations throughout the system's distribution system unless the system qualifies for one of the following exemptions: 1. If all TTHM and HAA5 samples collected under rule 335-7-2-.11 during an eight consecutive calendar quarter period beginning no earlier than the dates listed in the table below did not exceed 0.040 mg/L for TTHM and 0.030 mg/L for HAA5. (i) 40/30 Certification Date Table 40/30 Certification Due | Beginning date of eligible TTHM and HAA5 Data |
October 1, 2006 | January 2004 |
April 1, 2007 | January 2004 |
October 1, 2007 | January 2005 |
April 1, 2008 | January 2005 |
(ii) If a system is on reduced monitoring under rule 335-7-2-.11 and was not required to monitor during the period listed in the 40/30 Certification Date Table above, the system's eligibility must be based on compliance samples taken during the 12 months preceding the date listed in the table.(iii) Systems must certify to the Department that every individual compliance sample taken under rule 335-7-2-.11 during the specified period in subparagraph 1.(i) of this paragraph were = 0.040 mg/L for TTHM and = 0.030 mg/L for HAA5 and that the system has not had a monitoring violation for TTHMs or HAA5s.(iv) The Department may require the system to conduct a DSE under this rule even if the system meets the 40/30 certification requirements.(v) Systems must retain a complete copy of their certification submitted under this rule for 10 years after the date it was submitted.(vi) The certification, all data upon which the certification is based, and any Department notifications must be available for review by the Department or the public.(vii) The 40/30 certification must be submitted to the Department by the applicable date listed in subparagraph (2)(a)1. of this rule.2. A system that serves fewer than 500 people ( < 167 customers) and has at least one year of monitoring under rule 335-7-2-.11 is not required to conduct a DSE as outlined under this rule unless notified by the Department. Systems serving a population fewer than 500 people that have not monitored for at least 1 year under rule 335-7-2-.11 must complete a DSE as required under this rule.(c) Systems must comply with the requirements of this rule based upon the schedule in the following table. Systems that are a part of a combined distribution system must comply with the schedule in the table below based upon the population of the largest system in the combined distribution system as defined by the Department. DSE Schedule
System Population | Date to submit monitoring plan1, system specific study, 40/30 certification or very small system waiver: | Standard monitoring plan or system specific study must be complete by: | Submit DSE report or monitoring plan to the Department by:2 |
= 100,000 | October 1, 2006 | September 30, 2008 | January 1, 2009 |
50,000 - 99,999 | April 1, 2007 | March 31, 2009 | July 1, 2009 |
10,000 - 49,999 | October 1, 2007 | September 30, 2009 | January 1, 2010 |
< 10,000 | April 1, 2008 | March 31, 2010 | July 1,2010 |
1 If, within 12 months after the date identified in this column, the system does not receive notification from the Department that plan submitted has been reviewed and accepted, the system must consider the plan as submitted approved and conduct its monitoring accordingly.
2 If, within 3 months after the date listed in this column, the Department has not notified the system that its DSE report has been approved, the system may consider the report approved as submitted and must implement the recommended monitoring as required in rule 335-7-2-.12.
(d) Systems must complete a standard monitoring plan that meets the requirements in rule 335-7-2-.14 or a system specific study that meets the requirements in rule 335-7-2-.15 unless the system meets one of the exemption criteria in subparagraphs (b)1. and 2. of this rule.(e) DSE results will not be used for the purpose of determining compliance with the MCLs. However, the system must report the results of the DSE in the system's CCR.(f) Systems must conduct a DSE every 9 years if the system does not meet the exemption criteria in subparagraph (b) of this rule. Systems must conduct a DSE if any of the criteria listed in subparagraphs (f)1. through 5. of this rule are met after the initial DSE report is submitted. 1. The system adds a new surface water or ground water under the influence of surface water source or treatment plant that does not have the same entry point as another water plant.2. The system adds a new well or spring that is not considered in the same aquifer as the system's existing water sources.3. The system adds a new connection to another system that is going to be used more than 60 days a year or starts using an existing connection for more than 60 days a year, unless the water quality is similar to water already being purchased from the source system.4. The system consolidates with another water system. The resulting water system shall be responsible for conducting the DSE as required under this rule.5. The Department requires the system to conduct another DSE.(g) DSE reports must include the systems recommendations and justification for where and during what month(s) TTHM and HAA5 monitoring under rule 335-7-2-.12 should be conducted. The recommendations must be based on the following criteria: 1. Systems must select the number of monitoring locations specified in rule 335-7-2-.12. Systems will use these recommended locations as routine compliance monitoring locations under rule 335-7-2-.12 unless informed by the Department otherwise. The locations should be distributed throughout the distribution system to the extent possible.2. Systems must recommend compliance monitoring locations based on standard monitoring results, system specific study results, and monitoring conducted under rules 335-7-2-.11 or rule 335-7-2-.12. Systems must use the following protocol when making a determination concerning the compliance monitoring sites. Systems that are required to monitor at more than eight locations must repeat the protocol as necessary. Systems that do not have monitoring results under rule 335-7-2-.11 or do not have enough existing compliance monitoring locations under rules 335-7-2-.11 or 335-7-2-.12, must repeat the protocol below, skipping subparagraphs (g)2.(iii) through (vii) of this rule as necessary until the system has identified the required number of monitoring locations. (i) Location with the highest TTHM LRAA not previously selected as a compliance monitoring location.(ii) Location with the highest HAA5 LRAA not previously selected as a compliance monitoring location.(iii) Existing average residence time compliance monitoring location (maximum residence time compliance monitoring location for ground water systems) with the highest HAA5 LRAA not previously selected as a compliance monitoring location.(iv) Location with the highest TTHM LRAA not previously selected as a compliance monitoring location.(v) Location with the highest TTHM LRAA not previously selected as a compliance monitoring location.(vi) Location with the highest HAA5 LRAA not previously selected as a compliance monitoring location.(vii) Existing average residence time compliance monitoring location (maximum residence time compliance monitoring location for ground water systems) with the highest TTHM LRAA not previously selected as a compliance monitoring location.(viii) Location with the highest HAA5 LRAA not previously selected as a compliance monitoring location.3. Systems may recommend locations other than those specified in subparagraph (b) of this rule if the system includes a rationale for selecting other locations. Once the locations are approved by the Department, systems must monitor at these locations to determine compliance under rule 335-7-2-.12.4. The recommended compliance monitoring schedule must include the compliance monitoring during the month with historical peak concentrations for TTHM and HAA5, unless another month is approved by the Department. Once the peak historical month has been identified and the system is required to conduct routine monitoring at least quarterly, the system must schedule compliance monitoring under rule 335-7-2-.12.Ala. Admin. Code r. 335-7-2-.13
New Rule: Filed December 18, 2007; effective January 22, 2008. Amended: Filed April 21, 2009; effective May 26, 2009.Amended by Alabama Administrative Monthly Volume XXXIV, Issue No. 09, June 30, 2016, eff. 8/5/2016.Author: Dennis D. Harrison
Statutory Authority:Code of Ala. 1975, §§ 22-23-33, 22-23-49, 22-22A-5, 22-22A-6.