Jon Niermann, Chairman

Emily Lindley, Commissioner

Bobby Janecka, Commissioner

Toby Baker, Executive Director

We authorize you to use or reproduce any original material contained in this publication—that is, any material we did not obtain from other sources. Please acknowledge the TCEQ as your source.

Copies of this publication are available for public use through the Texas State Library, other state depository libraries, and the TCEQ Library, in compliance with state depository law. For more information on TCEQ publications visit our website at:

tceq.texas.gov/publications

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by the

Texas Commission on Environmental Quality

P.O. Box 13087

Austin TX 78711-3087

TCEQ is an equal opportunity employer. The agency does not allow discrimination on the basis of race, color, religion, national origin, sex, disability, age, sexual orientation or veteran status. In compliance with the Americans with Disabilities Act, this document may be requested in alternate formats by contacting TCEQ at 512-239-0010 or 1-800-RELAY-TX (TDD), or by writing P.O. Box 13087, Austin, TX 78711-3087.

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ii

Contents

Preface

This publication contains the language of Title 30, Texas Administrative Code, Chapter 290 (30 TAC 290), Subchapter E: Public Health Service (PHS) Fees, Subchapter F: Drinking Water Standards Governing Drinking Water Quality and Reporting Requirements for Public Water Supply Systems, and Subchapter H: Consumer Confidence Reports.

• Subchapter E covers the fees that public water systems (PWSs) must pay to the state.
• Subchapter F covers the requirements regarding drinking water quality at PWSs.
• Subchapter H covers the requirements for community PWSs to deliver an annual report of drinking water quality, called a Consumer Confidence Report (CCR), to their customers.

It contains the rule language for these three subchapters and is formatted to allow easy reference to individual rule elements.

What useful features are in this publication?

We have included the following features to help you use this document and hope you will find them to be useful:

15. A table of commonly used abbreviations will help you understand which

term in these rules corresponds to an abbreviation you encounter in a related publication.

15. The topics and section numbers at the top of each page will help you find information quickly. For example, to find the specific rules for water treatment, look for “Water Treatment” at the top of the page. To find out what 30 TAC §290.104(c)(2) says, look for “§290.104,” which is just below the corresponding topic.

15. The full citation for each part of the rule to avoid confusion. For example, you’ll see “§290.106(c)(2)(A)” instead of just that final letter “(A).”

Why these revisions?

This guidance document incorporates the most current rule language of 30 TAC 290 Subchapter E, F and H as of January 2019, as well as the following changes.

The 2015 through 2019 revisions to these rules:

• Addresses the updates for the EPA revised total coliform rule and groundwater rule (effective March 30, 2017).
• Makes minor changes to §290.117 for water quality parameters samples to be collected (effective March 30, 2017).
• Includes updates to the Fee structure (effective June 2, 2016).

We have links to the Texas Secretary of State’s official version of these rules on our website at <www.tceq.texas.gov/goto/rules/> and they were also published in the Texas Register on March 30, 2017.

This document reproduces the text of the rule as published on the Secretary of State’s (SOS) website. If there appears to be a discrepancy between this guide and the rules, follow the rules on the SOS website.

What other rules apply to public water systems in Texas?

Public water systems should be aware of all the rules pertaining to drinking water that are contained in various parts of the Texas regulations. A public water system must comply with all the applicable requirements. Each rule explains exactly which public water system it applies to. Some examples of additional rules and their locations within the regulations are given below:

• 30 TAC 290 Subchapter D. Rules and regulations for public water systems related to requirements for water treatment plant design, operation and maintenance. If you have questions about Subchapter D contact the Texas Commission on Environmental Quality’s (TCEQ) public drinking water program at 512-239-4691 or by e-mail at <pdws@tceq.texas.gov>.
• 30 TAC Chapter 291. Rules and regulations for public water systems related to capacity development. Contact the Plan Review Team at 512-239-4691 or by e-mail at <plandist@tceq.texas.gov> if you have questions about these requirements.
• 30 TAC Chapter 293. Rules and regulations for water districts. Contact the Water Districts Section at 512-239-4691 or by e-mail at <plandist@tceq.texas.gov> if you have questions about these requirements.
• 30 TAC Chapter 30. Requirements for certification of water works operators. TCEQ’s Operator Certification Team can answer questions about these requirements at 512-239-6133.
• 16 TAC Part 4, Chapter 76. Rules and regulations for water well drillers. If you have questions about these regulations, call 1-800-803-9202 or 512-463-8876 or go to the Texas Department of Licensing and Regulation (TDLR) Web site at <www.license.state.tx.us/wwd/wwd.htm>.
• 16 TAC Part 2, Chapter 24. Rules and regulations for water utilities related to requirements for rates and Certificates of Convenience and Necessity for utilities. Contact the Public Utility Commission at 512-936-7405 or by e-mail at <water@puc.texas.gov> if you have questions about these requirements.

The Department of State Health Services (DSHS) implements the Food and Drug Administration (FDA) and Texas regulations for water bottlers, water vendors, restaurants, day cares, hospitals and other entities that may own or operate public water systems. The TCEQ highly recommends that business owners and operators review the DSHS rules to determine if those rules apply to them.

Who can answer questions about these rules?

If you have questions about the rules described in this guidance document, contact the Texas Commission on Environmental Quality (TCEQ) Water Supply Division at 512-239-4691 or by e-mail at <pdws@tceq.texas.gov>.

Who enforces these rules?

The State of Texas has primacy over the regulation of public drinking water. This means that the TCEQ writes, adopts, and enforces rules that are at least as stringent as the rules promulgated by the U.S. Environmental Protection Agency (EPA). The Texas rules may be more specific than or worded differently from the EPA rules, so public water systems should become familiar with the Texas-specific rules.

How can I get copies of TCEQ rules, forms, and publications?

Here are ways you can obtain copies of rules, forms, or publications from the TCEQ:

15. E-mail your order to the Publications Section at <puborder@tceq.texas.gov>. Be

sure to provide your name, address, and the title and number of the publication you are requesting.

15. Go to the TCEQ website at <www.tceq.texas.gov>; under the Site Navigation bar, follow the links to “Rules,” “Forms,” or “Publications” to download copies.

15. Fax your order to 512-239-4488, or order by phone at 512-239-0028.

15. Write to TCEQ Publications, MC 195; PO Box 13087; Austin, TX 78711-3087.

If you don’t find the item you want, the TCEQ Publications Unit will help you find it. Contact them as shown above or by calling 512-239-0028. Try to give the rule, form, or publication number as well as the title. This information will help the TCEQ get the correct item to you as quickly as possible.

GUI groundwater under the direct influence of surface water. For regulatory purposes, GUI is subject to the same requirements as surface water.

GWR Ground Water Rule. The GWR, requiring raw water sampling, corrective action in response to detection of viral indicators, and notification of significant deficiencies, will became effective Dec. 1, 2009.

HAA haloacetic acid (a DBP). There are nine different HAAs that contain bromine, chlorine, or both, although only five of these are currently regulated.

HAA5 a specific group of five haloacetic acids. DBP1 and DBP2 set a maximum contaminant level (MCL) for the sum of the following five HAAs: monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), trichloroacetic acid (TCAA), monobromoacetic acid (MBAA), and dibromoacetic acid (DBAA).

HAAFP haloacetic acid formation potential. The theoretical maximum amount of HAA a given source of water can form.

HDT hydraulic detention time

IESWTR Interim Enhanced Surface Water Treatment Rule

IDSE Initial Distribution System Evaluation

LT1 Long Term 1 Enhanced Surface Water Treatment Rule

LT2 Long Term 2 Enhanced Surface Water Treatment Rule

MCL maximum contaminant level. The concentration level of a contaminant that is regulated. If a system has a contaminant concentration greater than the MCL, they may be in violation of the regulations. See RAA.

MCLG maximum contaminant level goal. The health-effects based ideal level for a contaminant. This is not the regulated concentration.

MDL method detection limit. The concentration below which a given method cannot accurately measure concentration. See BDL.

MOR monthly operating report

MRDL maximum residual disinfectant limit. EPA regulations establish these limits on the allowable concentration of disinfectant leaving a plant.

MRDLG maximum residual disinfectant limit goal

NTNC non-transient, non-community water system. A water system that serves the same

people all year, but is not a community. A school or factory may be a NTNC.

NTU Nephelometric turbidity unit. A measurement of the cloudiness of water. Turbidity monitoring is required at all surface water and GUI treatment plants.

PWS public water system

PWSID public water system identification number

RAA running annual average

SDWA Safe Drinking Water Act

SDWIS Safe Drinking Water Information System. The database of record for EPA drinking water quality data, also known as SWRL, for “SDWIS-Web Release.” The online form of this data is known as Drinking Water Watch. Texas data is available at <https://dww2.tceq.texas.gov/DWW/> and national data is available at <www.epa.gov/enviro/html/sdwis/sdwis_query.html>.

SCL secondary contaminant level

SOC synthetic organic chemical

SUVA specific ultraviolet absorbance

SW surface water

SWTP surface water treatment plant

SWTR Surface Water Treatment Rule

20. detention time (see HDT) or temperature

T10 effective contact time. The time within which 10 percent of a tracer material will have passed through a unit process. Theoretical T10 can be calculated by multiplying the baffling factor (BF) by the theoretical hydraulic detention time (HDT).

TCEQ Texas Commission on Environmental Quality, previously known as the Texas Natural Resource Conservation Commission before Sept. 1, 2002.

TEEX Texas Engineering Extension Service

THM trihalomethane (a DBP). These are halogenated organic molecules with one carbon, three halogens, and one hydrogen. The four THMs of interest are chloroform (three chlorines, also called “trichloromethane”), dichlorobromomethane, dibromochloromethane, and bromoform (a molecule containing three bromines; also called “tribromomethane”).

TNC Transient non-community water system

TNRCC Texas Natural Resource Conservation Commission, which became the Texas Commission on Environmental Quality (TCEQ) on Sept. 1, 2002.

TOC total organic carbon. A group parameter measuring the total amount of carbon in water present as organic molecules. The EPA is using TOC as a surrogate for DBPPs in the DBP1. See DOC.

Abbreviations and AcronymsTCEQ Publication RG-346

TTHM total trihalomethanes. The sum of the four THMs upon which compliance is based. TWDB Texas Water Development Board

TWUA Texas Water Utilities Association

UV ultraviolet

UV254 absorbance of ultraviolet light at a wavelength of 254 nanometers, measured in units of inverse length

VOC volatile organic chemical, volatile organic contaminant, or volatile organic compound

§290.51(a)(3)(C)(i) The number of connections will be determined from data collected from the latest agency inspection report.

§290.51(a)(3)(C)(ii) All nontransient noncommunity systems, state, federal, and other community water system installations determined by the commission to serve large populations through a few connections will have the number of connections for fee purposes determined by dividing the population served by a value of ten.

§290.51(a)(3)(C)(iii) Examples of such installations include, but are not limited to, universities, children’s homes, correctional facilities, and military facilities which generally do not bill customers for water service.

§290.51(a)(4) New public water systems will not be assessed a fee for services until water is supplied to the first connection.

§290.51(a)(5) The commission will charge a fee of $100 for services provided to noncommunity water systems which are not addressed in paragraph (3) of this subsection.

§290.51(a)(6) All fees are due by January 1 of each year, shall be paid by check, money order, electronic funds transfer, or through the agency’s payment portal, and shall be made payable to the Texas Commission on Environmental Quality. Penalties and interest for the late payment of fees shall be assessed in accordance with Chapter 12 of this title (relating to Payment of Fees).

§290.51(b) Failure to make payments as required under this section will subject the violator to the penalty provisions of the Texas Health and Safety Code, Chapter 341, Subchapter C.

§290.51(c) The commission may adjust the fee rates in subsection (a) of this section through an appropriate notification process, such as, but not limited to, Texas Register publication, based on the agency’s cost of administering the water programs.

Source Note: The provisions of this §290.51 adopted to be effective December 21, 1993, 18 TexReg 9105; amended to be effective February 14, 1997, 22 TexReg 1323; amended to be effective December 30, 2001, 26 TexReg 10616; amended to be effective July 30, 2009, 34 TexReg 4893; amended to be effective June 2, 2016, 41 TexReg 3906

§290.102. General Applicability

§290.102(a) General applicability. This subchapter shall apply to all public water systems as described in each section, unless the system:

§290.102(a)(1) consists only of distribution and storage facilities (and does not have any production and treatment facilities);

§290.102(a)(2) obtains all of its water from, but is not owned or operated by, a public water system to which such standards apply;

§290.102(a)(3) does not sell water to any person;

§290.102(a)(4) is not a carrier which conveys passengers in interstate commerce; and

§290.102(a)(5) is subject to plumbing restrictions and inspections by the public water system which provides the water.

§290.102(b) Variances and exemptions. Variances and exemptions may be granted at the discretion of the executive director according to the Safe Drinking Water Act (SDWA), 42 United States Code (USC), §300g-4 and §300g-5, and according to National Primary Drinking Water Regulations Implementation, Subpart K, 40 Code of Federal Regulations §§142.301 - 142.313. The executive director may not approve variances or exemptions from:

§290.102(b)(1) the maximum contaminant level (MCL) for Escherichia coli, nitrate, nitrite, or total nitrate and nitrite;

§290.102(b)(2) the maximum residual disinfection level for chlorine dioxide; or

§290.102(b)(3) the treatment technique requirements for filtration and disinfection.

§290.102(b)(4) Variances are prohibited for rules addressing microbial contaminants, including rules in §290.109 - 209.111 and §290.116 of this title (relating to Microbial Contaminants; Disinfectant Residuals; Surface Water Treatment; and Groundwater Corrective Actions and Treatment Techniques).

§290.102(c) Extensions. An extension to the compliance deadline for an MCL or treatment technique that becomes effective on or after January 1, 2002, may be granted at the discretion of the executive director in accordance with the SDWA, 42 USC, §300g-1(b)(10).

§290.102(c)(1) The executive director may extend the effective date of an MCL or treatment technique for up to two years if all of the following conditions apply:

§290.102(c)(1)(A) there are no acute violations associated with the new MCL or treatment technique for which the extension is being granted;

§290.102(c)(1)(B) the executive director determines that granting the extension will not result in an unreasonable risk to public health;

§290.102(c)(1)(C) the extension is granted only to public water systems that were in operation on the date that the MCL or treatment technique was promulgated by the United States Environmental Protection Agency (EPA);

§290.102(c)(1)(D) the executive director determines that capital improvements are needed to comply with the new MCL or treatment technique;

§290.102(c)(1)(E) the executive director approves a schedule identifying the capital improvements necessary to bring the system into compliance with the new MCL or treatment technique; and

§290.102(c)(1)(F) the EPA has not already incorporated a two-year extension into the effective date for the new MCL or treatment technique requirement.

§290.102(c)(2) An application for an extension must be submitted to the executive director in writing by the owner or responsible party of the water system. The request must include a statement identifying the new MCL or treatment technique which is not being met and a general long range plan for meeting the new requirement.

§290.102(c)(3) The executive director may issue an extension covering a group or class of systems with a common MCL or treatment technique which is not met without individual applications.

§290.102(d) Motion to overturn. Any person may file a motion to overturn the executive director’s decision to grant or deny a variance, exemption, or extension under this section according to the procedures set out in §50.139 of this title (relating to Motion to Overturn Executive Director’s Decision).

§290.102(e) Monitoring schedule. All monitoring required by this chapter shall be conducted in a manner and on a schedule approved by the executive director in concurrence with the requirements of the administrator of the EPA.

§290.102(f) Modified monitoring. When a public water system supplies water to one or more other public water systems, the executive director may modify the monitoring requirements imposed by this chapter to the extent that the interconnection of the systems justifies treating them as a single system for monitoring purposes. Any modified monitoring shall be conducted pursuant to a schedule specified by the executive director in concurrence with the requirements of the administrator of the EPA.

§290.102(g) The owner or operator of a public water system shall ensure that the executive director is provided with a copy of the results of any test, measurement, or analysis required by this subchapter. The copies shall be submitted within the first ten days following the month in which the result is received by the public water system, or the first ten days following the end of the required monitoring period as provided by this subchapter, whichever occurs first.

Source Note: The provisions of this §290.102 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective March 30, 2017, 42 TexReg 1466

§290.103. Definitions

The following definitions shall apply in the interpretation and enforcement of this subchapter. If a word or term used in this subchapter is not contained in the following list, its definition shall be as shown in §290.38 of this title (relating to Definitions) or in 40 Code of Federal Regulations (CFR) §141.2. Other technical terms used shall have the meanings or definitions listed in the latest edition of “Glossary, Water and Wastewater Control Engineering,” prepared by a joint editorial board representing the American Public Health Association, American Society of Civil Engineers, American Water Works Association, and the Water Pollution Control Federation.

§290.103(1) Assessment source monitoring--Raw groundwater source monitoring required by the executive director based on groundwater source susceptibility to fecal contaminants.

§290.103(2) Combined distribution system (CDS)--The interconnected distribution system consisting of the distribution systems of wholesale systems and of the consecutive systems that receive finished water.

§290.103(2)(A) The executive director may determine that the CDS does not include certain systems based on factors such as providing or receiving a relatively small amount of water or only on an emergency basis.

§290.103(2)(B) A public water system may be determined to be in a different CDS for the purposes of compliance with regulations based on the Stage 2 Disinfection Byproducts Rule (DBP2) and the Long Term Stage 2 Enhanced Surface Water Treatment Rule (LT2).

§290.103(2)(B)(i) For the purposes of raw water monitoring under LT2, the CDS shall be based on the retail and wholesale population served by each surface water treatment plant or plant treating groundwater under the direct influence of surface water.

§290.103(2)(B)(ii) For the purposes of DBP2, the CDS shall be determined based on the retail population served within each individual system’s distribution system.

§290.103(3) Compliance cycle--The nine-year (calendar year) cycle during which public water systems must monitor. Each compliance cycle consists of three, three-year compliance periods.

§290.103(4) Compliance period--A three-year (calendar year) period within a compliance cycle. Each compliance cycle has three, three-year compliance periods. Within the first compliance cycle, the first compliance period is called the initial compliance period.

§290.103(5) Comprehensive performance evaluation (CPE)-- A thorough review and analysis of a treatment plant’s performance-based capabilities and the associated administrative, operation and maintenance practices. It is conducted to identify factors that may be adversely impacting a plant’s capability to achieve compliance and to emphasize approaches

TCEQ Publication RG-346§290.103. Definitions

that can be implemented without significant capital improvements. The comprehensive performance evaluation consists of the following components: assessment of plant performance; evaluation of major unit processes; identification and prioritization of performance limiting factors; assessment of the applicability of comprehensive technical assistance; and preparation of a CPE report.

§290.103(6) Consecutive system--A public water system that receives some or all of its finished water from one or more other public water systems.

§290.103(7) Disinfection profile--A summary of daily Cryptosporidium, Giardia lamblia and viral inactivation obtained through disinfection at the treatment plant.

§290.103(8) Disinfection by-products (DBP)--Chemical compounds formed by the reaction of a disinfectant with the natural organic matter present in water.

§290.103(9) Domestic or other non-distribution system plumbing problem--A coliform contamination problem in a public water system with more than one service connection that is limited to the specific service connection from which the coliform-positive sample was taken.

§290.103(10) DPD--Abbreviation for N,N-diethyl-p-phenylenediamine, a reagent used in the determination of several residuals. DPD methods are available for both volumetric (titration) and colorimetric determinations, and are commonly used in the field as part of a colorimetric test kit.

§290.103(11) Dual sample set--A set of two samples collected at the same time and same location, with one sample analyzed for total trihalomethanes (TTHM) and the other sample analyzed for haloacetic acids-group of five (HAA5). Dual sample sets are collected for the purposes of conducting an initial distribution system evaluation and determining compliance with the TTHM and HAA5 maximum contaminant levels.

§290.103(12) Enhanced coagulation--The removal of disinfection by-product precursors to a specified level by conventional coagulation and sedimentation.

§290.103(13) Enhanced softening--The removal of disinfection by-product precursors to a specified level by softening.

§290.103(14) Entry point--Any point where a source of treated water first enters the distribution system. Entry points to the distribution system may include points where chlorinated well water, treated surface water, rechlorinated water from storage, or water purchased from another supplier enters the distribution system.

§290.103(15) Entry point sampling site--A sampling site representing the quality of the water entering the distribution system at each designated entry point.

§290.103(16) Fecal indicators--Microbiological organisms used to indicate the presence of fecal contamination. Examples include; fecal coliform, Escherichia coli (E. coli), enterococci, and coliphage.

§290.103. DefinitionsTCEQ Publication RG-346

§290.103(17) Filter assessment--An in-depth evaluation of an individual filter, including the analysis of historical filtered water turbidity from the filter, development of a filter profile, evaluation of media condition, identification and prioritization of factors limiting filter performance, appraisal of the applicability of corrections, and preparation of a filter self- assessment report.

§290.103(18) Filter profile--A graphical representation of individual filter performance, based on continuous turbidity measurements or total particle counts versus time for an entire filter run. The filter profile must include all the data collected from the time that the filter placed into service until the time that the backwash cycle is complete and the filter is restarted. The filter profile must also include data collected as another filter is being backwashed.

§290.103(19) Finished water--Water that is introduced into the distribution system of a public water system and intended for distribution and consumption without further treatment, except as necessary to maintain water quality within the distribution system (e.g., booster disinfection, addition of corrosion control chemicals).

§290.103(20) Groundwater corrective action--Action required when a raw groundwater source sample is found to be positive for Escherichia coli (E. coli) or other fecal indicators as described under §290.116(b) of this title (relating to Groundwater Corrective Actions and Treatment Techniques).

§290.103(21) Groundwater corrective action plan--A plan approved by the executive director documenting the steps to be taken to address fecal contamination of a groundwater source as described under §290.116(b) of this title (relating to Groundwater Corrective Actions and Treatment Techniques). The groundwater corrective action plan must be approved within 30 days of being notified of the fecal contamination.

§290.103(22) Groundwater system--For the purposes of compliance with §290.109 of this title (relating to Microbial Contaminants) and with §290.116 of this title (relating to Groundwater Corrective Actions and Treatment Techniques), a public water system that provides, uses, or distributes any groundwater except if the groundwater is combined with surface water (or with groundwater under the direct influence of surface water) prior to treatment.

§290.103(23) Haloacetic acids (five) (HAA5)--The sum of the monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid concentrations in milligrams per liter, rounded to two significant figures after adding the sum.

§290.103(24) Halogen--One of the chemical elements chlorine, bromine, or iodine.

§290.103(25) Hydrogeologic sensitivity assessment--A determination of whether groundwater systems obtain water from hydrogeologically sensitive sources.

§290.103(26) Level 1 assessment--An evaluation to identify the possible presence of sanitary defects, defects in distribution system coliform monitoring practices, and (when possible) the likely reason that the public water system triggered the assessment. Minimum

TCEQ Publication RG-346§290.103. Definitions

elements include review and identification of atypical events that could affect distributed water quality or indicate that distributed water quality was impaired; changes in distribution system maintenance and operation that could affect distributed water quality (including, but not limited to water storage); source and treatment considerations that bear on distributed water quality, where appropriate; existing water quality monitoring data; and inadequacies in sample sites, sampling protocol, and sample processing. The public water system must conduct the assessment consistent with any executive director directives that tailor specific assessment elements with respect to the size and type of the public water system and the size, type, and characteristics of the distribution system.

§290.103(27) Level 2 assessment--An evaluation to identify the possible presence of sanitary defects, defects in distribution system coliform monitoring practices, and (when possible) the likely reason that the public water system triggered the assessment. A Level 2 assessment provides a more detailed examination of the public water system (including, but not limited to the public water system’s monitoring and operational practices) than does a Level 1 assessment through the use of a more comprehensive investigation and review of available information, additional internal and external resources, and other relevant practices. Minimum elements include review and identification of atypical events that could affect distributed water quality or indicate that distributed water quality was impaired; changes in distribution system maintenance and operation that could affect distributed water quality (including, but not limited to water storage); source and treatment considerations that bear on distributed water quality, where appropriate; existing water quality monitoring data; and inadequacies in sample sites, sampling protocol, and sample processing. The public water system must conduct the assessment consistent with any executive director directives that tailor specific assessment elements with respect to the size and type of the public water system and the size, type, and characteristics of the distribution system. The public water system must comply with any expedited actions or additional actions required by the executive director in the case of an Escherichia coli (E.coli) maximum contaminant level violation.

§290.103(28) Locational running annual average (LRAA)--The average of analytical results for samples taken at a specific monitoring location during the previous four calendar quarters.

§290.103(29) Maximum contaminant level (MCL)--The maximum concentration of a regulated contaminant that is allowed in drinking water before the public water system is cited for a violation. MCLs for regulated contaminants are defined in the applicable sections of this subchapter.

§290.103(30) Maximum residual disinfectant level (MRDL)--The disinfectant concentration that may not be exceeded in the distribution system. There is convincing evidence that addition of a disinfectant is necessary for control of waterborne microbial contaminants.

§290.103(31) Minimum acceptable disinfectant residual--The lowest disinfectant concentration allowed in the distribution system for microbial control.

§290.103(32) Operational evaluation level (OEL)--Calculated level of total trihalomethanes (TTHM) or haloacetic acid group of five (HAA5), an exceedance of which

§290.103. DefinitionsTCEQ Publication RG-346

requires a system to perform an evaluation of factors in the distribution system contributing to disinfection by-product formation and submit an operation evaluation report as described in §290.115(e)(2) of this title (relating to Stage 2 Disinfection Byproducts (TTHM and HAA5)). The OEL at any monitoring location is the sum of the two previous quarters’ results plus twice the current quarter’s result, divided by 4 to determine an average.

§290.103(33) Raw water--Water prior to any treatment including disinfection that is intended to be used, after treatment, as drinking water.

§290.103(33)(A) Raw groundwater is water from a groundwater source.

§290.103(33)(B) Raw surface water is any water from a surface water source or from a groundwater under the direct influence of surface water source.

§290.103(34) Raw groundwater source monitoring--Fecal indicator sampling at untreated groundwater sources including triggered source water and assessment source monitoring.

§290.103(35) Sanitary defect--A defect that could provide a pathway of entry for microbial contamination into the distribution system or that is indicative of a failure or imminent failure in a barrier that is already in place.

§290.103(36) Seasonal public water system--A noncommunity public water system that is not operated as a public water system on a year-round basis and starts up and shuts down at the beginning and end of each operating season.

§290.103(37) Significant deficiency--Significant deficiencies cause, or have the potential to cause, the introduction of contamination into water delivered to customers. This could include defects in design, operation, or maintenance of the source, treatment, storage, or distribution systems.

§290.103(38) Specific ultraviolet absorption at 254 nanometers (nm) (SUVA)--An indirect indicator of whether the organic carbon in water is humic or non-humic. It is calculated by dividing a sample’s ultraviolet absorption at a wavelength of 254 nm (UV254) (in inverse meters) by its concentration of dissolved organic carbon (DOC) (in milligrams per liter).

§290.103(39) Total organic carbon (TOC)--The concentration of total organic carbon, in milligrams per liter, measured using heat, oxygen, ultraviolet irradiation, chemical oxidants, or combinations of these oxidants that convert organic carbon to carbon dioxide, rounded to two significant figures. TOC is a surrogate measure for precursors to formation of disinfection by- products.

§290.103(40) Total trihalomethanes (TTHM)--The sum of the chloroform, dibromochloromethane, bromodichloromethane, and bromoform concentrations in milligrams per liter, rounded to two significant figures after summing.

§290.103(41) Triggered source water monitoring--Raw groundwater source monitoring required for systems not providing at least 4-log treatment of viruses when a routine distribution coliform sample is positive.

§290.103(42) Trihalomethane (THM)--One of the family of organic compounds named as derivatives of methane, wherein three of the four hydrogen atoms in methane are each substituted by a halogen atom in the molecular structure.

§290.103(43) Wholesale system--A public water system that delivers water to another public water system.

§290.103(44) 4-log treatment--At least 99.99% (4-log) treatment of viruses using inactivation, removal, or an executive director-approved combination of 4-log virus inactivation and removal. The 4-log treatment must be able to be properly validated and achieved before the first connection of the specified water source.

Source Note: The provisions of this §290.103 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective November 8, 2012, 37 TexReg 8849; amended to be effective March 30, 2017, 42 TexReg 1466

§290.104. Summary of Maximum Contaminant Levels,

Maximum Residual Disinfectant Levels, Treatment

Techniques, and Action Levels

§290.104(a) Summary table purpose. The maximum contaminant levels (MCLs), maximum residual disinfectant levels (MRDLs), treatment techniques, and action levels are presented in this section as a reference source. Only the regulatory concentrations are shown in these tables. Compliance requirements are given in the specific section for each chemical.

§290.104(b) MCLs for inorganic compounds. The MCLs for inorganic contaminants listed in this subsection apply to public water systems as provided in §290.106 of this title (relating to Inorganic Contaminants).

Table 1: §290.104(b) MCLs for Inorganic Contaminants

§290.104(c) MCLs for organic compounds. The following MCLs for synthetic organic contaminants and volatile organic contaminants apply to public water systems as provided in §290.107 of this title (relating to Organic Contaminants).

Table 2: §290.104(c)(1) MCLs for Synthetic Organic Contaminants

§290.104(c)(2) The following are the MCLs for volatile organic contaminants.

Table 3: §290.104(c)(2) MCLs for Volatile Organic Contaminants

§290.104(d) MCLs for radionuclide contaminants. MCLs for radionuclide contaminants apply to public water systems as provided in §290.108 of this title (relating to Radionuclides Other than Radon).

§290.104(e) Microbial contaminants. The MCL for microbial or bacteriological contaminants applies to public water systems as provided in §290.109 of this title (relating to Microbial Contaminants). The MCL for microbiological contaminants is based on the presence or absence of Escherichia coli (E. coli).

§290.104(f) Minimum residual disinfectant concentrations and MRDLs. Minimum residual disinfectant concentrations and MRDLs apply to public water systems as provided in §290.110 of this title (relating to Disinfectant Residuals).

§290.104(f)(1) The minimum residual disinfectant concentration in the water entering the distribution system is 0.2 milligrams per liter (mg/L) free chlorine or 0.5 mg/L chloramine.

§290.104(f)(2) The minimum residual disinfectant concentration in the water within the distribution system is 0.2 mg/L free chlorine or 0.5 mg/L chloramine.

§290.104(f)(3) The MRDL of chlorine dioxide in the water entering the distribution system is 0.8 mg/L.

§290.104(f)(4) The MRDL of free chlorine or chloramine in the water within the distribution system is 4.0 mg/L based on a running annual average.

§290.104(g) Surface water treatment. Systems treating surface water or groundwater under the direct influence of surface water must meet the turbidity treatment technique requirements as provided in §290.111 of this title (relating to Surface Water Treatment).

§290.104(g)(1) The turbidity level of the combined filter effluent must never exceed 1.0 nephelometric turbidity unit (NTU) and the turbidity level of the combined filter effluent must be 0.3 NTU or less in at least 95% of the samples tested each month.

§290.104(g)(2) Systems are subject to the raw water monitoring, pathogen removal and inactivation and individual filter turbidity provisions of §290.111 of this title.

§290.104(h) Disinfection by-product precursors. The treatment technique requirements for disinfection by-product precursors apply to water systems as provided in §290.112 of this title (relating to Total Organic Carbon (TOC)).

§290.104(i) Disinfection by-products (total trihalomethanes (TTHM) and haloacetic acids (HAA5)). The MCLs for TTHM and HAA5 apply to water systems as provided in §290.113 of this title (relating to Stage 1 Disinfection By-products (TTHM and HAA5)) and in §290.115 of this title (relating to Stage 2 Disinfection By-products (TTHM and HAA5)). The MCLs for TTHM and HAA5 are:

§290.104(i)(1) 0.080 mg/L for TTHM; and

§290.104(i)(2) 0.060 mg/L for HAA5.

§290.104(j) Disinfection by-products other than TTHM and HAA5. The MCLs for chlorite and bromate apply to water systems as provided in §290.114 of this title (relating to Other Disinfection By-products (Chlorite and Bromate)). The MCLs for chlorite and bromate are as follows:

§290.104(j)(1) 1.0 mg/L for chlorite; and

§290.104(j)(2) 0.010 mg/L for bromate.

§290.104(k) Lead and copper action levels. The action levels for lead and copper apply to water systems as provided in §290.117 of this title (relating to Regulation of Lead and Copper). Action levels for lead and copper are as follows:

§290.104(k)(1) 0.015 mg/L for lead; and

§290.104(k)(2) 1.3 mg/L for copper.

§290.104(l) Recycle streams. The treatment technique requirements for recycle streams are specified in §290.42(c)(6) and (d)(3) of this title (relating to Water Treatment).

Source Note: The provisions of this §290.104 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective February 19, 2004, 29 TexReg 1373; amended to be effective December 23, 2004, 29 TexReg 11729; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective March 30, 2017, 42 TexReg 1466

§290.105. Summary of Secondary Standards

§290.105(a) Summary table purpose. The secondary constituent levels are presented in this section as a reference source. Only the regulatory concentration is shown in these tables. Compliance requirements are given in §290.118 of this title (relating to Secondary Standards).

§290.105(b) Secondary standards. The secondary standards apply to all public water systems as provided in §290.118 of this title (relating to Secondary Constituent Levels). The maximum levels for secondary constituents are listed in the following table:

Table 4: §290.105(b) Secondary Standards

Source Note: The provisions of this §290.105 adopted to be effective September 13, 2000, 25 TexReg 8880

§290.106. Inorganic Contaminants

§290.106(a) Applicability. All public water systems are subject to the requirements of this section.

§290.106(a)(1) Community and nontransient, noncommunity systems shall comply with the requirements of this section regarding monitoring, reporting, and maximum contaminant levels (MCLs) for all inorganic contaminants (IOCs) listed in this section.

§290.106(a)(2) Transient, noncommunity systems shall comply with the requirements of this section regarding monitoring, reporting, and MCL for nitrate and nitrite.

§290.106(a)(3) For purposes of this section, systems using groundwater under the direct influence of surface water shall meet the inorganic sampling requirements given for surface water systems.

§290.106(b) MCLs for IOCs. The MCLs for IOCs listed in the following table apply to community and nontransient, noncommunity water systems. The MCLs for nitrate, nitrite, and total nitrate and nitrite also apply to transient, noncommunity water systems.

Table 5: §290.106(b) MCLs for Inorganic Contaminants

§290.106(c) Monitoring requirements for IOCs. Public water systems shall monitor for IOCs at the locations specified by the executive director. All monitoring conducted under the requirements of this section must be conducted at sites designated in the public water system’s monitoring plan. Each public water system shall monitor at the time designated during each compliance period.

§290.106(c)(1) Routine monitoring locations for IOCs except asbestos. Antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, nitrate, nitrite, selenium, and thallium shall be monitored at each entry point to the distribution system.

§290.106(c)(1)(A) If a system draws water from more than one source and the sources are combined before distribution, the system must sample at an entry point that is representative of all sources and during periods of normal operating conditions.

§290.106(c)(1)(B) Systems shall take all subsequent samples at the same entry point to the distribution system unless the executive director determines that conditions make another entry point more representative of the source or treatment plant being monitored.

§290.106(c)(1)(C) The executive director may approve the use of composite samples.

§290.106(c)(1)(C)(i) Compositing must be done in the laboratory or in the field by persons designated by the executive director.

§290.106(c)(1)(C)(ii) Compositing shall be allowed only at groundwater entry points to the distribution system.

§290.106(c)(1)(C)(iii) Compositing shall be allowed only within a single system. Samples from different systems shall not be included in a composite sample.

§290.106(c)(1)(C)(iv) No more than five individual samples shall be included in a composite sample.

§290.106(c)(1)(C)(v) The maximum number of individual samples allowed in a composite sample shall not exceed the number obtained by dividing the MCL for the contaminant by the detection limit of the analytical method and rounding the quotient to the next lowest integer. Detection limits for each analytical method are as listed in 40 Code of Federal Regulations (CFR) §141.23(a)(4)(i).

§290.106(c)(1)(C)(vi) If the concentration in the composite sample is greater than or equal to the proportional contribution of the MCL (e.g., 20% of MCL when five points are composited) for any inorganic chemical, then a follow-up sample must be collected from each sampling point included in the composite sample.

§290.106(c)(1)(C)(vi)(I) Follow-up samples must be collected within 14 days of receipt of the composite sample results.

§290.106(c)(1)(C)(vi)(II) If duplicates of the original sample taken from each entry point to the distribution system used in the composite are

available, the system may use these instead of resampling. The duplicates must be analyzed within 14 days of the composite.

§290.106(c)(1)(C)(vi)(III) The follow-up or duplicate samples must be analyzed for the contaminant(s) which were excessive in the composite sample.

§290.106(c)(1)(D) Initial monitoring for a new water source must be conducted at a site representative of the water quality of the new source of water. For systems with one well and one entry point, initial monitoring may be conducted at the entry point to the distribution system.

§290.106(c)(2) Monitoring locations for asbestos. Asbestos shall be monitored at locations where asbestos contamination is most likely to occur.

§290.106(c)(2)(A) A system vulnerable to asbestos contamination due solely to source water shall sample at the entry point to the distribution system.

§290.106(c)(2)(B) A system vulnerable to asbestos contamination due solely to corrosion of asbestos-cement pipe shall sample at a tap served by asbestos-cement pipe, under conditions where asbestos contamination is most likely to occur.

§290.106(c)(2)(C) A system vulnerable to asbestos contamination due both to its source water supply and corrosion of asbestos-cement pipe shall sample at a tap served by asbestos-cement pipe, under conditions where asbestos contamination is most likely to occur.

§290.106(c)(2)(D) The executive director may require additional sampling locations based on the size, length, age, and location of asbestos-cement pipe in the distribution system. The system must provide information regarding the size, length, age, and location of asbestos-cement pipe in the distribution system to the executive director upon request.

§290.106(c)(3) Initial monitoring frequency for IOCs except asbestos. Prior to using water as a drinking water source, public water systems shall monitor at the frequency determined by the executive director to ensure that the water distributed to customers will comply with the MCLs for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, nitrate, nitrite, nitrate and nitrite (total), mercury, selenium, and thallium.

§290.106(c)(4) Monitoring frequency for IOCs except asbestos, nitrate, and nitrite. Community and nontransient, noncommunity public water systems shall monitor for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium, and thallium at the following frequency.

§290.106(c)(4)(A) Routine monitoring frequency. A public water system shall routinely monitor for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium, and thallium.

§290.106(c)(4)(A)(i) Each groundwater entry point shall be sampled once every three years.

§290.106(c)(4)(A)(ii) Each surface water entry point shall be sampled annually.

§290.106(c)(4)(A)(iii) Each of the sampling frequencies listed in this paragraph constitutes one round of sampling for groundwater and surface water entry points, respectively.

§290.106(c)(4)(B) Reduced monitoring. The executive director may reduce the monitoring frequency for a system that has completed a minimum of three rounds of sampling by granting a waiver to the routine monitoring frequency for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium, and thallium.

§290.106(c)(4)(B)(i) Systems that use a new water source are not eligible for a waiver until three rounds of sampling from the new source have been completed.

§290.106(c)(4)(B)(ii) To be considered for a waiver, systems shall demonstrate that all previous analytical results at that sample site were less than the MCL.

§290.106(c)(4)(B)(iii) In determining the appropriate reduced monitoring frequency, the executive director shall consider:

§290.106(c)(4)(B)(iii)(I) the reported contaminant concentrations from all previous samples;

§290.106(c)(4)(B)(iii)(II) the degree of variation in reported concentrations; and

§290.106(c)(4)(B)(iii)(III) other factors that may affect contaminant concentrations such as changes in groundwater pumping rates, changes in the system’s configuration, changes in the system’s operating procedures, or changes in the flow or characteristics of a reservoir or stream used as the water source.

§290.106(c)(4)(B)(iv) If the executive director grants a waiver, it shall be made in writing and shall set forth the basis for the determination. The determination may be initiated by the executive director. The executive director shall review and, where appropriate, revise the waiver of monitoring frequency when other data relevant to the system becomes available.

§290.106(c)(4)(B)(v) The term during which the waiver is effective shall not exceed one compliance cycle (i.e., nine years).

§290.106(c)(4)(B)(vi) A system must take a minimum of one sample during each compliance cycle while the waiver is effective.

§290.106(c)(4)(C) Increased monitoring. The executive director may increase the monitoring frequency for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium, or thallium.

§290.106(c)(4)(C)(i) If the results from a sample site exceed any of the MCLs in subsection (b) of this section, the system shall immediately begin quarterly sampling at that sample site starting in the next quarter after the exceedance occurs.

§290.106(c)(4)(C)(ii) After the initiation of quarterly monitoring, the executive director may return a system to the routine monitoring frequency if monitoring shows that the sampling site is reliably and consistently below the MCL.

§290.106(c)(4)(C)(ii)(I) The executive director shall not decrease the quarterly sampling requirement until a groundwater system has taken a minimum of two quarterly samples.

§290.106(c)(4)(C)(ii)(II) The executive director shall not decrease the quarterly sampling requirement until a surface water system has taken a minimum of four quarterly samples.

§290.106(c)(5) Asbestos monitoring frequency. Community and nontransient, noncommunity water systems shall monitor for asbestos at the following frequency.

§290.106(c)(5)(A) A public water system shall routinely monitor for asbestos once during the first three years of each compliance cycle.

§290.106(c)(5)(B) The executive director may waive the routine monitoring frequency requirements for asbestos.

§290.106(c)(5)(B)(i) When determining if a waiver should be granted, the executive director shall consider:

§290.106(c)(5)(B)(i)(I) the potential for asbestos contamination of the water source;

§290.106(c)(5)(B)(i)(II) the use of asbestos-cement pipe for finished water distribution; and

§290.106(c)(5)(B)(i)(III) the corrosivity of the water.

§290.106(c)(5)(B)(ii) If the executive director grants a waiver, it shall be made in writing and shall set forth the basis for the determination. The determination may be initiated by the executive director. The executive director

shall review and, where appropriate, revise the waiver of monitoring frequency when other data relevant to the system becomes available.

§290.106(c)(5)(B)(iii) The term during which the waiver is effective shall not exceed one compliance cycle (i.e., nine years).

§290.106(c)(5)(C) The executive director may increase the monitoring frequency for asbestos.

§290.106(c)(5)(C)(i) A system that exceeds the MCL for asbestos shall sample quarterly beginning in the next quarter after the violation occurs.

§290.106(c)(5)(C)(ii) After the initiation of quarterly sampling, the executive director may return a system to the routine monitoring frequency if monitoring shows that the system is reliably and consistently below the MCL.

§290.106(c)(5)(C)(ii)(I) The executive director shall not decrease the quarterly sampling requirement until a groundwater system has taken a minimum of two quarterly samples.

§290.106(c)(5)(C)(ii)(II) The executive director shall not decrease the quarterly sampling requirement until a surface (or combined surface water and groundwater) water system has taken a minimum of four quarterly samples.

§290.106(c)(6) Nitrate monitoring frequency. All public water systems shall monitor for nitrate at the following frequency.

§290.106(c)(6)(A) Routine nitrate monitoring frequency. All public water systems shall routinely monitor for nitrate.

§290.106(c)(6)(A)(i) All public water systems shall annually sample at each groundwater entry point to the distribution system.

§290.106(c)(6)(A)(ii) A community or nontransient, noncommunity water system shall sample quarterly at each surface water entry point to the distribution system.

§290.106(c)(6)(A)(iii) A transient, noncommunity water system shall sample annually at each surface water entry point to the distribution system.

§290.106(c)(6)(B) Reduced nitrate monitoring frequency. The executive director may reduce the monitoring frequency for community or nontransient, noncommunity water systems using surface water sources by granting a waiver to the routine monitoring frequency.

§290.106(c)(6)(B)(i) To be considered for a waiver, a system shall demonstrate that the nitrate concentration in each sample collected during the previous four consecutive quarters was less than 50% of the nitrate MCL.

§290.106(c)(6)(B)(ii) If the executive director grants a waiver, it shall be made in writing and shall set forth the basis for the determination. The determination may be initiated by the executive director. The executive director shall review and, where appropriate, revise the waiver of monitoring frequency when other data relevant to the system becomes available.

§290.106(c)(6)(B)(iii) A system that receives a waiver to the routine nitrate monitoring frequency must sample annually for nitrate. The annual sample must be collected in the quarter that previously resulted in the highest nitrate concentration.

§290.106(c)(6)(C) Increased nitrate monitoring frequency. The executive director may increase the nitrate monitoring frequency for community or nontransient, noncommunity water systems using groundwater sources.

§290.106(c)(6)(C)(i) A system that is sampling annually shall begin quarterly nitrate sampling if the nitrate concentration in any sample is equal to or greater than 50% of the nitrate MCL. Quarterly sampling must begin the first quarter after the elevated nitrate level was detected.

§290.106(c)(6)(C)(ii) After the initiation of quarterly sampling, the executive director may return a system to the routine annual nitrate monitoring frequency if quarterly sampling shows that the system is reliably and consistently below the nitrate MCL for a minimum of four consecutive quarters.

§290.106(c)(7) Nitrite monitoring frequency. All public water systems shall monitor for nitrite at the following frequency.

§290.106(c)(7)(A) All public water systems shall routinely take one nitrite sample during each nine-year compliance cycle. All public water systems shall monitor at the time designated by the executive director during each compliance period during each nine-year compliance cycle. New entry points will be scheduled for nitrite sample collection during the first year of operation, and then every nine years thereafter unless increased nitrite monitoring is required in accordance with this paragraph.

§290.106(c)(7)(B) The executive director may reduce the monitoring frequency for nitrite by granting a waiver to the routine monitoring frequency.

§290.106(c)(7)(B)(i) To be considered for a waiver, a system shall demonstrate that the nitrite concentration in the initial sample was less than 50% of the nitrite MCL.

§290.106(c)(7)(B)(ii) If the executive director grants a waiver, it shall be made in writing and shall set forth the basis for the determination. The determination may be initiated by the executive director. The executive director shall review and, where appropriate, revise the waiver of monitoring frequency when other data relevant to the system becomes available.

§290.106(c)(7)(B)(iii) A system that receives a waiver to the routine nitrite monitoring frequency must sample at a frequency specified by the executive director.

§290.106(c)(7)(C) The executive director may increase the monitoring frequency for nitrite.

§290.106(c)(7)(C)(i) A system shall sample quarterly for at least one year following any sample in which the nitrite concentration is greater than or equal to 50% of the MCL.

§290.106(c)(7)(C)(ii) The executive director may allow a system to return to the routine monitoring frequency after determining the system is reliably and consistently less than the MCL.

§290.106(c)(8) Confirmation sampling for all IOCs. The executive director may require a public water system to confirm the results of any individual sample.

§290.106(c)(8)(A) If a sample result exceeds the MCL, a public water system may be required to collect one additional sample to confirm the results of the initial test. If an additional sample is required:

§290.106(c)(8)(A)(i) Confirmation samples must be collected at the same entry point to the distribution system as the sample that exceeded the MCL;

§290.106(c)(8)(A)(ii) Confirmation samples for IOCs except nitrate and nitrite shall be collected as soon as possible after the system receives the analytical results of the first sample; and

§290.106(c)(8)(A)(iii) Confirmation samples for nitrate and nitrite shall be collected within 24 hours of the system’s receipt of notification of the analytical results of the first sample. Systems unable to comply with the 24-hour sampling requirement must immediately notify the consumers served by the public water system in accordance with subsection (f) of this section. Systems exercising this option must take and analyze a confirmation sample within two weeks of notification of the analytical results of the first sample.

§290.106(c)(8)(B) The executive director may require a confirmation sample for any sample with questionable results.

§290.106(c)(9) More frequent monitoring. The executive director may require more frequent monitoring than specified in paragraphs (4) – (7) of this subsection.

§290.106(d) Analytical requirements for IOCs. Analytical procedures shall be performed in accordance with §290.119 of this title (relating to Analytical Procedures). Testing for inorganic contaminants shall be performed at a laboratory certified by the executive director.

§290.106(e) Reporting requirements for IOCs. The owner or operator of a public water system shall ensure that the executive director is provided with a copy of the results of any test, measurement, or analysis required by this subsection. The copies must be submitted within the first ten days following the month in which the result is received by the public water system, or the first ten days following the end of the required monitoring period as provided by this subsection, whichever occurs first. The copies must be mailed to the Texas Commission on Environmental Quality, Water Supply Division, MC 155, P.O. Box 13087, Austin, Texas 78711- 3087.

§290.106(f) Compliance determination for IOCs. Compliance with this section shall be determined using the following criteria.

§290.106(f)(1) Compliance with the MCL for each IOC shall be based on the analytical results obtained at each individual sampling point.

§290.106(f)(2) A public water system that exceeds the levels for nitrate, nitrite, or the sum of nitrate and nitrite specified in subsection (b) of this section commits an acute MCL violation. Compliance shall be based on the results of the single sample. If a confirmation sample is collected, compliance shall be based on the average result of the original and confirmation samples.

§290.106(f)(3) A public water system that exceeds the levels of antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium, or thallium (i.e., any IOC except nitrate and nitrite) specified in subsection (b) of this section at any sampling point commits an MCL violation.

§290.106(f)(3)(A) For systems that are sampling annually or less frequently, compliance may be based on the results of a single sample, if a confirmation sample is not collected.

§290.106(f)(3)(B) For systems that are sampling annually or less frequently, if a confirmation sample is collected, compliance will be based on the average result of the original and confirmation samples.

§290.106(f)(3)(C) For systems that are sampling more frequently than annually, compliance is based on the running annual average for each sampling point.

§290.106(f)(3)(D) If a single quarterly sample would cause the running annual average to be exceeded, then the system is immediately out of compliance.

§290.106(f)(4) Any result below the method detection limits of 40 CFR §141.23(a)(4)(i) shall be considered to be zero for the purpose of calculating compliance.

§290.106(f)(5) The executive director may exclude the results of obvious sampling errors from the compliance calculations.

§290.106(f)(6) Compliance with the IOC MCLs must be based on the results of all samples required by the executive director, regardless of whether that number is greater or less than the minimum required number.

§290.106(f)(7) For purposes of determining compliance, arsenic results must be reported to the nearest 0.001 milligram per liter.

§290.106(f)(8) A public water system that fails to do a required public notice or certify that the public notice has been performed commits a public notice violation.

§290.106(g) Public notice for IOCs. A public water system that violates the requirements of this section must notify the executive director and the system’s customers.

§290.106(g)(1) A public water system that violates the MCL for nitrate, nitrite, or the sum of nitrate and nitrite shall notify the executive director within 24 hours and the water system customers of this acute violation in accordance with the requirements of §290.122(a) of this title (relating to Public Notification).

§290.106(g)(2) A public water system that violates the MCL for nitrate, nitrite, or the sum of nitrate and nitrite that is unable to comply with the 24-hour confirmation sampling requirement must immediately notify the consumers served by the public water system in accordance with §290.122(a) of this title.

§290.106(g)(3) A public water system that fails to meet the MCL for any of the regulated IOCs except nitrate and nitrite (i.e., antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium, and thallium) shall notify the executive director by the end of the next business day and the water system customers in accordance with the requirements of §290.122(b) of this title.

§290.106(g)(4) A public water system that fails to conduct the monitoring required by this section must notify its customers of the violation in accordance with the requirements of §290.122(c) of this title.

§290.106(g)(5) If a public water system has a distribution system separable from other parts of the distribution system with no interconnections, the executive director may allow the system to give public notice to only the area served by that portion of the system that is out of compliance.

§290.106(h) Best available technology (BAT) for IOCs. BAT for treatment of violations of MCLs in subsection (b) of this section are listed in 40 CFR §141.62.

§290.106(i) Small system compliance technologies (SSCTs) for arsenic. SSCTs for arsenic are listed in 40 CFR §141.62(d) and may be utilized with commission approval. When point-of-use or point-of-entry devices are used for compliance, the water system must develop a program for the long-term operation, maintenance, and monitoring of the devices to ensure adequate performance.

§290.106(j) Bottled water. In accordance with 40 CFR §141.101, bottled water may be used on a temporary basis only and with approval by the commission in order to avoid unreasonable risk to health.

Source Note: The provisions of this §290.106 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective February 19, 2004, 29 TexReg 1373; amended to be effective December 23, 2004, 29 TexReg 11729; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective March 30, 2017, 42 TexReg 1466

§290.107. Organic Contaminants

§290.107(a) Applicability. All community and nontransient, noncommunity water systems shall comply with the requirements of this section regarding organic contaminants. For purposes of this section, systems using groundwater under the direct influence of surface water shall meet the organic sampling requirements given for surface water systems.

§290.107(b) Maximum contaminant levels (MCLs) for organic contaminants. The concentration of synthetic and volatile organic chemicals shall not exceed the MCLs specified in this section.

§290.107(b)(1) The following are MCLs for synthetic organic chemical (SOC) contaminants.

Table 6: §290.107(b)(1) MCLs for Synthetic Organic Contaminants

§290.107(b)(2) The following are MCLs for volatile organic chemical (VOC) contaminants.

Table 7: §290.107(b)(2) MCLs for Volatile Organic Contaminants

§290.107(b)(3) Each public water system must certify annually to the executive director (using third-party or manufacturer’s certification) that when acrylamide or epichlorohydrin are used in drinking water systems, the combination (or product) of dose and monomer level does not exceed 0.05% dosed at 1.0 milligrams per liter (mg/L) (or equivalent) for acrylamide and 0.01% dosed at 20 mg/L (or equivalent) for epichlorohydrin.

§290.107(c) Monitoring requirements for organic contaminants. Public water systems shall monitor for organic contaminants at the locations and frequency in paragraphs (1) and (2) of this subsection. All monitoring conducted under the requirements of this section must be conducted at sites designated in the public water system’s monitoring plan. All samples must be taken during periods of normal operation.

§290.107(c)(1) SOC monitoring requirements. Monitoring of the SOC contaminants shall be conducted at the frequency and locations given in this paragraph.

§290.107(c)(1)(A) SOC monitoring locations. Monitoring of the SOC contaminants shall be conducted at the following locations.

§290.107(c)(1)(A)(i) Systems shall routinely sample at sample sites representative of each entry point to the distribution system.

§290.107(c)(1)(A)(ii) Subsequent samples must be taken at the same sample site unless the executive director determines that a change in conditions makes a different sample site more representative of the water available to customers.

§290.107(c)(1)(A)(iii) The executive director must approve any change in sampling location.

§290.107(c)(1)(B) Initial SOC monitoring frequency. Prior to using a new source of water as drinking water, public water systems shall monitor at the frequency established by the executive director to ensure that the water distributed to customers will comply with the MCLs for SOCs.

§290.107(c)(1)(C) Routine SOC monitoring frequency. Monitoring of the SOC contaminants shall be conducted at the following frequency.

§290.107(c)(1)(C)(i) Community and nontransient, noncommunity water systems shall take four consecutive quarterly samples for each SOC contaminant listed in subsection (b)(1) of this section during each compliance period beginning with the initial compliance period.

§290.107(c)(1)(C)(ii) Community and nontransient, noncommunity water systems serving more than 3,300 persons that do not detect a contaminant in the initial compliance period may reduce the sampling frequency at that sample site to a minimum of two consecutive quarterly samples in one year during each repeat compliance period.

§290.107(c)(1)(C)(iii) Community and nontransient, noncommunity water systems serving 3,300 persons or fewer that do not detect a contaminant in the initial compliance period may reduce the sampling frequency at that sample site to a minimum of one sample during each repeat compliance period.

§290.107(c)(1)(C)(iv) Each public water system shall monitor at the time designated by the executive director within each compliance period.

§290.107(c)(1)(D) Increased SOC monitoring. The executive director may change the monitoring frequency for SOCs.

§290.107(c)(1)(D)(i) Entry points that exceed the SOC MCLs of subsection (b)(1) of this section as determined by subsection (f) of this section must be monitored quarterly. After a minimum of four quarterly samples shows the system is in compliance and the executive director determines the system is reliably and consistently below the MCL, as determined by the methods specified in subsection (f) of this section, the executive director may allow the system to monitor annually. Systems that monitor annually must monitor during the quarter that previously yielded the highest analytical result.

§290.107(c)(1)(D)(ii) The executive director may change the monitoring frequency if an organic SOC contaminant is detected in any sample.

§290.107(c)(1)(D)(ii)(I) If an organic SOC contaminant is detected in any sample, the system must monitor quarterly at each entry point to the distribution system at which a detection occurs.

§290.107(c)(1)(D)(ii)(II) After a system collects a minimum of two consecutive quarterly samples at a groundwater sample site, the executive director may decrease the quarterly monitoring requirement specified in subclause (I) of this clause, if the sample site is reliably and consistently below the MCL.

§290.107(c)(1)(D)(ii)(III) After a system collects a minimum of four consecutive quarterly samples at a surface water sample site or a groundwater under the direct influence of surface water sample site, the executive director may decrease the quarterly monitoring requirement specified in subclause (I) of this clause, if the sample site is reliably and consistently below the MCL.

§290.107(c)(1)(D)(ii)(IV) After the executive director determines that a sample site is reliably and consistently below the MCL, the executive director may allow the sample site to be monitored annually. Systems that monitor annually must monitor during the quarter that previously yielded the highest analytical result.

§290.107(c)(1)(D)(ii)(V) Sample sites that have three consecutive annual samples with no detection of a contaminant may be granted a waiver at the discretion of the executive director. The executive director will consider the waiver for each compliance period.

§290.107(c)(1)(D)(ii)(VI) If monitoring results in detection of one or more of certain related contaminants (i.e., heptachlor and heptachlor epoxide), then subsequent monitoring shall analyze for all related contaminants.

§290.107(c)(1)(D)(iii) The executive director may increase the required SOC monitoring frequency, where necessary, to detect variations within the system (e.g., fluctuations in concentration due to seasonal use, changes in water source, etc.).

§290.107(c)(1)(D)(iv) The executive director may require a confirmation sample for positive or negative results. If a confirmation sample is required by the executive director, the result must be averaged with the first sampling result and the average used for the compliance determination as specified in subsection (f) of this section. The executive director has discretion to delete results of obvious sampling errors from this calculation.

§290.107(c)(1)(E) Waivers for SOC monitoring. The executive director may grant a waiver to reduce the SOC monitoring frequency from the monitoring frequency requirements of subparagraphs (B) and (C) of this paragraph, based on previous use of the contaminant within the watershed or zone of influence of the water source. Examples of use of a contaminant include transport, storage, or disposal. If a determination by the executive director reveals no previous use of the contaminant within the watershed or zone of influence, a waiver may be granted. If the executive director cannot determine whether the contaminant has been used in the watershed or if the contaminant has been used previously, then the following factors shall be used to determine whether a waiver is granted:

§290.107(c)(1)(E)(i) previous analytical results;

§290.107(c)(1)(E)(ii) the proximity of the system to a potential point or non- point source of contamination. Point sources include spills and leaks of chemicals at or near a water treatment facility or at drinking water sources, manufacturing, distribution, or storage facilities, or from hazardous and municipal waste landfills and other waste handling or treatment facilities. Non- point sources include the use of pesticides to control insects, weeds, or pests on agricultural areas, forest lands, home and garden property, or other land application uses;

§290.107(c)(1)(E)(iii) the environmental persistence and transport of the pesticide herbicide or contaminant;

§290.107(c)(1)(E)(iv) how well the water source is protected against contamination due to such factors as depth of the well, type of soil, and the integrity of well construction. Surface water systems must consider watershed vulnerability and protection;

§290.107(c)(1)(E)(v) elevated nitrate levels at the water supply source; and

§290.107(c)(1)(E)(vi) use of polychlorinated byphenyls (PCBs) in equipment used in the production, storage, or distribution of water (i.e., PCBs used in pumps, transformers, etc.).

§290.107(c)(1)(F) Compositing for SOC monitoring. The executive director may reduce the total number of samples required from a system for analysis by allowing the use of compositing. Composite samples from a maximum of five entry points to the distribution system are allowed. Compositing of samples must be done in the laboratory and analyzed within 14 days of sample collection.

§290.107(c)(1)(F)(i) If any of the SOC contaminants listed in subsection (b)(1) of this section are detected in a composite sample, then a follow-up sample must be taken from each entry point to the distribution system included in the composite and analyzed within 14 days of collection.

§290.107(c)(1)(F)(ii) If duplicates of the original SOC sample taken from each entry point to the distribution system used in the composite are available, the executive director may use these duplicates instead of resampling. The duplicate must be analyzed within 14 days of collection and the results reported to the executive director.

§290.107(c)(1)(F)(iii) Compositing may only be permitted at entry points to the distribution system within a single system.

§290.107(c)(2) VOC monitoring requirements. Monitoring of the VOC contaminants shall be conducted at the frequency and locations given in this paragraph.

§290.107(c)(2)(A) VOC monitoring locations. Monitoring of the VOC contaminants shall be conducted at the following locations.

§290.107(c)(2)(A)(i) Systems shall routinely sample at sample sites representative of each entry point to the distribution system.

§290.107(c)(2)(A)(ii) Subsequent samples must be taken at the same sample site unless the executive director determines that a change in conditions makes a different sample site more representative of the water available to customers.

§290.107(c)(2)(A)(iii) The executive director must approve any change in sampling location.

§290.107(c)(2)(B) Initial VOC monitoring frequency. Prior to using water as a drinking water source, public water systems shall monitor at the frequency established by the executive director to ensure that the water distributed to customers will comply with the MCLs for VOCs.

§290.107(c)(2)(C) Routine VOC monitoring frequency. Monitoring of the VOC contaminants shall be conducted at the following frequency.

§290.107(c)(2)(C)(i) Community and nontransient, noncommunity water systems shall take four consecutive quarterly samples for each VOC contaminant listed in subsection (b)(2) of this section during each compliance period, beginning with the initial compliance period.

§290.107(c)(2)(C)(ii) If the initial monitoring for VOC contaminants has been completed, and the system did not detect any VOC contaminant listed in subsection (b)(2) of this section, the system shall take one sample annually beginning with the initial compliance period.

§290.107(c)(2)(C)(iii) After a minimum of three years of annual sampling, the executive director may allow groundwater systems with no previous detection of any VOC contaminant listed in subsection (b)(2) of this section to take one sample during each compliance period.

§290.107(c)(2)(C)(iv) Each community and nontransient, noncommunity groundwater system that does not detect a VOC contaminant listed in subsection (b)(2) of this section may be granted a waiver from the annual or triennial requirements of subsection (c)(2)(C)(ii) and (iii) of this section after completing the initial monitoring. For the purposes of this section, detection is defined as an analytical result of 0.0005 mg/L or greater. A waiver shall be effective for no more than six years (two compliance periods).

§290.107(c)(2)(C)(v) Each public water system shall monitor at the time designated by the executive director within each compliance period.

§290.107(c)(2)(D) Increased VOC monitoring. The executive director may change the monitoring frequency for VOCs.

§290.107(c)(2)(D)(i) Sample sites that exceed the VOC MCLs of subsection (b)(2) of this section, as determined by subsection (f) of this section, must be monitored quarterly. After a minimum of four consecutive quarterly samples that show the system is in compliance as specified in subsection (f) of this section and after the executive director determines that the system is reliably and consistently below the MCL, the executive director may allow the system to monitor annually during the quarter that previously yielded the highest analytical result.

§290.107(c)(2)(D)(ii) The executive director may require a confirmation sample for positive or negative results. If a confirmation sample is required by the executive director, the result must be averaged with the first sampling result and the average is used for the compliance determination as specified by subsection (f) of this section. The executive director has discretion to delete results of obvious sampling errors from this calculation.

§290.107(c)(2)(D)(iii) If a VOC contaminant listed in subsection (b)(2) of this section is detected at a level exceeding 0.0005 mg/L in any sample, then:

§290.107(c)(2)(D)(iii)(I) the system must monitor quarterly at each entry point to the distribution system that resulted in a detection;

§290.107(c)(2)(D)(iii)(II) the executive director may decrease the quarterly monitoring requirement specified in subsection (c)(2)(D)(iii)(I) of this section provided that the executive director has determined that the system is reliably and consistently below the MCL. In no case shall the executive director make this determination unless a groundwater system takes a minimum of two quarterly samples and a surface water system takes a minimum of four quarterly samples;

§290.107(c)(2)(D)(iii)(III) if the executive director determines that the system is reliably and consistently below the MCL, the executive director may allow the system to monitor annually. Systems that monitor annually must monitor during the quarter that previously yielded the highest analytical result;

§290.107(c)(2)(D)(iii)(IV) systems which have three consecutive annual samples with no detection of a contaminant may be granted a waiver as specified in subparagraph (E) of this paragraph; and

§290.107(c)(2)(D)(iii)(V) groundwater systems that have detected one or more of the following two-carbon organic compounds: trichloroethylene, tetrachloroethylene, 1,2-dichloroethane, 1,1,1- trichloroethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, or 1,1-dichloroethylene shall monitor quarterly for vinyl chloride. A vinyl chloride sample shall be taken at each entry point to the distribution system at which one or more of the two-carbon organic compounds was detected. If the result of the first analysis does not detect vinyl chloride, the executive director may reduce the quarterly monitoring frequency for vinyl chloride to one sample during each compliance period. Surface water systems are required to monitor for vinyl chloride as specified by the executive director.

§290.107(c)(2)(D)(iv) The executive director may increase the required VOC monitoring frequency, where necessary, to detect variations within the system (e.g., fluctuations in concentration due to seasonal use, changes in water source, etc.).

§290.107(c)(2)(E) Waivers for VOC monitoring. The executive director may grant a waiver after evaluating the previous use (including transport, storage, or disposal) of the contaminant within the watershed or zone of influence of the water sources. If a determination by the executive director reveals no previous use of the contaminant within the watershed or zone of influence, a waiver may be granted. If previous use of the contaminant is unknown or it has been used previously, then the following factors shall be used to determine whether a waiver is granted:

§290.107(c)(2)(E)(i) previous analytical results;

§290.107(c)(2)(E)(ii) the proximity of the system to a potential point or non- point source of contamination. Point sources include spills and leaks of chemicals at or near a water treatment facility or at drinking water sources manufacturing, distribution, or storage facilities, or from hazardous and municipal waste landfills and other waste handling or treatment facilities;

§290.107(c)(2)(E)(iii) the environmental persistence and transport of the contaminants;

§290.107(c)(2)(E)(iv) the number of persons served by the public water system and the proximity of a smaller system to a larger system;

§290.107(c)(2)(E)(v) how well the water source is protected against contamination (e.g., is it a surface or groundwater system). Groundwater systems must consider factors such as depth of the well, the type of soil, and well construction. Surface water systems must consider watershed protection;

§290.107(c)(2)(E)(vi) as a condition of the waiver, a groundwater system must take one sample at each entry point to the distribution system during the time the waiver is effective (i.e., one sample during two compliance periods or six years) and update its vulnerability assessment considering the factors listed in this paragraph. Based on this updated vulnerability assessment, the executive director must reconfirm that the system is not vulnerable. If the executive director does not make this reconfirmation within three years of the initial determination, then the waiver is invalid and the system is required to sample annually; and

§290.107(c)(2)(E)(vii) community and nontransient surface water systems that do not detect a VOC contaminant listed in subsection (b)(2) of this section may be considered by the executive director for a waiver from the annual sampling requirements of subparagraph (C)(ii) of this paragraph after completing the initial monitoring. Systems meeting this criteria must be determined by the executive director to be non-vulnerable based on a vulnerability assessment during each compliance period. Each system receiving a waiver shall sample at the frequency specified by the executive director (if any).

§290.107(c)(2)(F) Compositing for VOC monitoring. The executive director may reduce the total number of samples a system must analyze by allowing the use of compositing. Composite samples from a maximum of entry points to the distribution system are allowed. Compositing of samples must be done in the laboratory and analyzed within 14 days of sample collection.

§290.107(c)(2)(F)(i) If the VOC concentration in the composite sample is 0.0005 mg/L or greater for any contaminant listed in subsection (b)(2) of this section, then a follow-up sample must be taken and analyzed within 14 days from each entry point to the distribution system included in the composite.

§290.107(c)(2)(F)(ii) If duplicates of the original sample taken from each entry point to the distribution system used in the composite are available, the system may use these instead of resampling. The duplicate must be analyzed within 14 days of collection.

§290.107(c)(2)(F)(iii) Compositing may only be permitted by the executive director at entry points to the distribution system within a single system.

§290.107(c)(2)(F)(iv) Procedures for compositing VOC samples are as stated in 40 Code of Federal Regulations (CFR) §141.24(f)(14)(iv).

§290.107(d) Analytical requirements for organic contaminants. Analytical procedures shall be performed in accordance with §290.119 of this title (relating to Analytical Procedures). Testing for organic contaminants shall be performed at a laboratory certified by the executive director.

§290.107(e) Reporting requirements for organic contaminants. The owner or operator of a public water system shall ensure the executive director is provided with a copy of the results of any test, measurement, or analysis required by this subsection. The copies must be submitted within the first ten days following the month in which the result is received by the public water system, or the first ten days following the end of the required monitoring period as provided by this subsection, whichever occurs first. The copies must be mailed to the Water Supply Division, MC 155, Texas Commission on Environmental Quality, P.O. Box 13087, Austin, Texas 78711-3087.

§290.107(f) Compliance determination for organic contaminants. Compliance with the MCLs of subsection (b)(1) and (2) of this section shall be determined based on the analytical results obtained at each entry point to the distribution system.

§290.107(f)(1) If one sampling point is in violation of any MCL in subsection (b) of this section, then the system is in violation of the MCL for that contaminant.

§290.107(f)(1)(A) For systems monitoring more than once per year, compliance with the MCL is determined by a running annual average at each sampling point.

§290.107(f)(1)(B) Systems monitoring annually or less frequently whose sample result exceeds the MCL must begin quarterly sampling; systems will not be considered in violation of the MCL until they have completed one year of quarterly sampling.

§290.107(f)(1)(C) If any sample result will cause the running annual average to exceed the MCL at any sampling point, the system is out of compliance with the MCL immediately.

§290.107(f)(1)(D) If a system fails to collect the required number of samples, compliance will be based on the total number of samples collected.

§290.107(f)(1)(E) If a sample result is less than the detection limit, zero will be used to calculate the annual average.

§290.107(f)(2) The executive director has the authority to determine compliance or initiate enforcement action based upon analytical results and other information compiled by sanctioned representatives and agencies.

§290.107(f)(3) A public water system that fails to do a required public notice or certify that the public notice has been performed commits a public notice violation.

§290.107(g) Public notification requirements for organic contaminants. A public water system that violates the requirements of this section must notify the executive director and the system’s customers. If a public water system has a distribution system separate from other parts of the distribution system with no interconnections, the executive director may allow the system to give public notice to only that portion of the system that is out of compliance.

§290.107(g)(1) A system that violates an MCL given in subsection (b) of this section, shall report to the executive director and notify the public as provided under §290.122(b) of this title (relating to Public Notification).

§290.107(g)(2) A public water system that fails to conduct the monitoring required by this section must notify its customers of the violation in accordance with the requirements of §290.122(c) of this title.

§290.107(h) Best available technology for organic contaminants. Best available technology for treatment of violations of MCLs in subsection (b) of this section are listed in 40 CFR §141.61. Copies are available for review in the Water Supply Division, MC 155, Texas Commission on Environmental Quality, P.O. Box 13087, Austin, Texas 78711-3087.

Source Note: The provisions of this §290.107 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective February 19, 2004, 29 TexReg 1373; amended to be effective December 23, 2004, 29 TexReg 11729; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective March 30, 2017, 42 TexReg 1466

§290.108. Radionuclides Other than Radon

§290.108(a) Applicability. All community water systems shall comply with the requirements of this section regarding radionuclide contaminants. Public water systems treating groundwater under the direct influence of surface water must comply with the radionuclide requirements for surface water systems. Public water systems shall comply with the initial monitoring requirements.

§290.108(b) Maximum contaminant levels (MCL). The concentration of radionuclide contaminants in the water entering the distribution system shall not exceed the following MCLs.

§290.108(b)(1) MCLs for naturally occurring radionuclides are as follows:

§290.108(b)(1)(A) 5 picoCuries per liter (pCi/L) for combined radium-226 and radium-228, as calculated by the summation of the results for radium-226 and radium-228;

§290.108(b)(1)(B) 15 pCi/L for gross alpha particle activity (including radium-226 but excluding radon and uranium); and

§290.108(b)(1)(C) 30 micrograms per liter for uranium.

§290.108(b)(2) MCLs for beta particle and photon radioactivity from man-made radionuclides in drinking water in community water systems are equivalent to the MCLs under 40 Code of Federal Regulations (CFR) §141.66(d), as amended and adopted in the CFR through December 7, 2000 (65 FR 76708), which is adopted by reference.

§290.108(c) Monitoring requirements. Public water systems shall measure the concentration of radionuclides at locations and frequencies specified in the system’s monitoring plan. All samples must be collected during normal operating conditions.

§290.108(c)(1) Monitoring frequency for naturally occurring radionuclides. The monitoring frequency requirements for gross alpha particle activity, combined radium- 226 and radium-228, and uranium are as follows.

§290.108(c)(1)(A) Initial monitoring frequency. All systems that use a new source of water must begin to conduct initial monitoring of the new source within 90 days after initiating use of the source.

§290.108(c)(1)(A)(i) If the initial monitoring results are at or above an MCL, the system must perform quarterly monitoring as described in subparagraph (C) of this paragraph.

§290.108(c)(1)(A)(ii) If the initial monitoring results are below all of MCLs given in subsection (b)(1) of this section, the system shall perform routine monitoring as described in subparagraph (B) of this paragraph.

§290.108(c)(1)(B) Routine monitoring. The results of samples collected during initial and routine monitoring periods will be used to determine the monitoring frequency for subsequent monitoring periods.

§290.108(c)(1)(B)(i) If the results for all contaminants (gross alpha particle activity, combined radium-226 and radium-228, and uranium) are below the detection limits specified in Table A of this clause, the system must collect and analyze at least one sample at that sampling point once every nine years.

Table 8: §290.108(c)(1)(B)(i) Table A: Detection Limits for

Radionuclides

§290.108(c)(1)(B)(ii) If the result for any contaminant is at or above the detection limit but at or below one-half the MCLs given in subsection (b) of this section, the system must collect and analyze at least one sample at that sampling point every six years.

§290.108(c)(1)(B)(iii) If the result for any contaminant is above one-half the MCLs given in subsection (b) of this section but below the MCL, the system must collect and analyze at least one sample at that sampling point every three years.

§290.108(c)(1)(B)(iv) If the result for any contaminant is at or above any of the MCLs given in subsection (b) of this section, monitoring must be performed at the frequency given in subparagraph (C) of this paragraph.

§290.108(c)(1)(C) Increased monitoring. A system must perform increased monitoring if any results at a sampling point are at or above the MCLs, or at the direction of the executive director.

§290.108(c)(1)(C)(i) If the results for any contaminant are at or above any of the MCLs given in subsection (b) of this section, consecutive quarterly monitoring must be performed at that sample point.

§290.108(c)(1)(C)(ii) If the average of quarterly monitoring results is less than the MCLs in subsection (b) of this section, the sample point may be returned to the routine sampling frequency given in subparagraph (B) of this paragraph.

§290.108(c)(1)(C)(iii) To fulfill quarterly monitoring requirements 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.

§290.108(c)(1)(C)(iv) The analytical results from a composite sample will be treated as the annual average to determine compliance with the MCLs and future monitoring frequency requirements.

§290.108(c)(1)(C)(v) When required by the executive director, more frequent monitoring must be conducted in the vicinity of mining or other operations that may contribute alpha particle radioactivity to either surface or groundwater sources of drinking water, or when changes in the distribution system or treatment processing occur that may increase the concentration of radionuclide in the finished water.

§290.108(c)(1)(C)(vi) Community public water systems shall conduct monitoring when required by the executive director.

§290.108(c)(1)(D) Historical data. A system may use historical data to comply with the initial monitoring requirement, if approved by the executive director.

§290.108(c)(1)(D)(i) A system having only one entry point to the distribution system may use the monitoring data from the previous entry point or distribution system compliance monitoring to satisfy initial monitoring requirements.

§290.108(c)(1)(D)(ii) A system with multiple entry points that has appropriate historical monitoring data for each entry point to the distribution system may use previous compliance monitoring data to satisfy initial monitoring requirements.

§290.108(c)(1)(D)(iii) To satisfy initial monitoring requirements, a community water system with appropriate historical data for a representative point in the distribution system may use the monitoring data from the distribution system, provided that the executive director finds that the historical data satisfactorily demonstrates that each entry point to the distribution system is expected to be in compliance based upon the historical data and reasonable assumptions about the variability of contaminant levels between entry points.

§290.108(c)(1)(E) Sample invalidation. The executive director may invalidate the results of obvious sampling or analytic errors.

§290.108(c)(1)(F) Confirmation samples. The executive director may require more frequent monitoring or may require confirmation samples at the executive director’s discretion.

§290.108(c)(1)(G) Sampling scheduling. Systems shall monitor at the time designated by the executive director.

§290.108(c)(2) Monitoring and compliance for man-made radionuclides.

The monitoring and compliance requirements for man-made radionuclide under 40 CFR

§141.26(b), as amended and adopted in the CFR through December 7, 2000 (65 FR 76708), are adopted by reference.

§290.108(c)(3) Monitoring locations for radionuclide contaminants. Systems must monitor at sample sites described in the system’s monitoring plan.

§290.108(c)(3)(A) Initial monitoring for a new water source must be conducted at a site representative of the water quality of the new source of water.

§290.108(c)(3)(B) Routine compliance monitoring for the radionuclide covered by this section must be performed at sampling points representing each entry point to the distribution system. If results from an entry point exceed one-half the MCL, the executive director may require the system to sample all water sources providing water to that entry point.

§290.108(d) Analytical requirements for radionuclide contaminants. Analytical procedures shall be performed in accordance with §290.119 of this title (relating to Analytical Procedures). Testing for radionuclide contaminants shall be performed at a laboratory certified by the executive director.

§290.108(e) Reporting requirements. The owner or operator of a public water system must ensure the executive director is provided with a copy of the results of any test, measurement, or analysis required by this section. The copies must be submitted within the first ten days following the month in which the result is received by the public water system, or the first ten days following the end of the required monitoring period as provided by this subsection, whichever occurs first. The copies must be mailed to the Water Supply Division, MC 155, Texas Commission on Environmental Quality, P.O. Box 13087, Austin, Texas 78711-3087.

§290.108(f) Compliance determination. Compliance with the requirements of this section shall be determined as follows.

§290.108(f)(1) If the running average annual MCL for gross alpha particle activity, combined radium-226 and radium-228, or uranium as set forth in subsection (b) of this section is exceeded, based on quarterly monitoring results, the system has committed an MCL violation.

§290.108(f)(1)(A) 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% (1.65 theta where theta is the standard deviation of the net counting rate of the sample).

§290.108(f)(1)(B) When the gross alpha particle activity exceeds 5 pCi/L, the same or an equivalent sample shall be analyzed for radium-226 and radium-228.

§290.108(f)(1)(C) 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, one-half the detection limit will be used to calculate the annual average.

§290.108(f)(1)(D) The results of all samples taken and analyzed under the provisions of this section will be used in determining compliance, even if that number is greater or less than the minimum required.

§290.108(f)(1)(E) If a system fails to complete required increased monitoring, the executive director may base compliance on all available sample results.

§290.108(f)(1)(F) If the results at one sample site are in violation, the public water system is in violation.

§290.108(f)(1)(G) When confirmation samples are collected, the average of an initial sample and its confirmation sample must be averaged for the purposes of determining compliance.

§290.108(f)(1)(H) To judge compliance with the MCLs, sample results must be rounded to the same number of significant figures as the MCL for the substance in question.

§290.108(f)(2) If the average annual MCL for man-made radionuclide set forth in subsection (b) of this section is exceeded, the system has committed an MCL violation.

§290.108(f)(3) A public water system that fails to conduct the monitoring tests required by this subsection commits a monitoring violation.

§290.108(f)(4) A public water system that fails to report the results of the monitoring tests required by this subsection commits a reporting violation.

§290.108(f)(5) A public water system that fails to do a required public notice or certify that the public notice has been performed commits a public notice violation.

§290.108(g) Public notification. A public water system that violates the requirements of this section must notify the executive director and the system’s customers, as follows.

§290.108(g)(1) A public water system that violates the MCL for gross alpha particle activity, combined radium-226 and radium-228, or uranium shall give notice to the executive director and notify the public as required by §290.122(b) of this title (relating to Public Notification).

§290.108(g)(2) The operator of a community water system that violates the MCL for man-made radionuclide shall give notice to the executive director and to the public as required by §290.122(b) of this title.

§290.108(g)(3) A public water system that fails to conduct the monitoring required by this subsection must notify its customers of the violation in accordance with the requirements of §290.122(c) of this title.

§290.108(h) Best available technology for radionuclides other than radon. Best available technology for treatment of violations of MCLs in subsection (b) of this section are listed in 40 CFR §141.66(g).

§290.108(i) Small system compliance technologies (SSCTs) for radionuclides. SSCTs for radionuclides are listed in 40 CFR §141.66(h) and may be utilized with commission approval. When point-of-use or point-of-entry devices are used for compliance, the water system must develop a program for the long-term operation, maintenance, and monitoring of the devices to ensure adequate performance.

§290.108(j) Bottled water. In accordance with 40 CFR §141.101, bottled water may be used on a temporary basis only and with approval by the commission in order to avoid unreasonable risk to health.

Source Note: The provisions of this §290.108 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective December 23, 2004, 29 TexReg 11729; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective March 30, 2017, 42 TexReg 1466

§290.109. Microbial Contaminants

§290.109(a) Applicability. All public water systems must produce and distribute water that meets the provisions of this section regarding microbial contaminants.

§290.109(b) Maximum contaminant levels (MCL) for microbial contaminants. Treatment techniques and MCL requirements for microbial contaminants are based on detection of those contaminants or fecal indicator organisms.

§290.109(b)(1) A public water system is in compliance with the MCL for Escherichia coli (E. coli) unless any of the following conditions occur:

§290.109(b)(1)(A) The public water system has an E. coli-positive repeat sample following a total-coliform-positive routine sample;

§290.109(b)(1)(B) The public water system has a total coliform-positive repeat sample following an E. coli-positive routine sample;

§290.109(b)(1)(C) The public water system fails to take all required repeat samples following an E. coli-positive routine sample; or

§290.109(b)(1)(D) The public water system fails to test for E. coli when any repeat sample tests positive for total coliform.

§290.109(b)(1)(E) The E. coli MCL is defined as when a condition described in subparagraphs (A) - (D) of this paragraph occurs.

§290.109(b)(2) For public water systems required to collect raw groundwater samples, the standard is no detection of fecal indicators in a raw groundwater sample.

§290.109(c) Treatment technique triggers and assessment requirements for microbial contaminants. All public water systems shall comply with the requirements as described in this subsection. Public water systems shall conduct assessments after exceeding any of the treatment technique triggers as described in paragraphs (1) and (2) of this subsection.

§290.109(c)(1) Level 1 treatment technique triggers are:

§290.109(c)(1)(A) For a public water system which collects 40 or more distribution samples per month, the treatment technique trigger is defined as when more than 5.0% of samples collected in a month are total coliform-positive.

§290.109(c)(1)(B) For a public water system which collects fewer than 40 distribution samples per month, the treatment technique trigger is defined as when two or more samples collected in a month are total coliform-positive.

§290.109(c)(1)(C) When a public water system fails to collect all required repeat samples after a total coliform-positive result.

§290.109(c)(2) Level 2 treatment technique triggers are:

§290.109(c)(2)(A) An E. coli MCL violation as specified in subsection (b)(1)(A) -

(D) of this section occurs.

§290.109(c)(2)(B) A second Level 1 treatment technique trigger occurs as defined in paragraph (1) of this subsection, within a rolling 12-month period. If the executive director has determined the reason that the samples that caused the first Level 1 treatment technique trigger were total coliform-positive and has established that the public water system has corrected the problem, a public water system will not be required to conduct and complete a Level 2 assessment. The public water system shall have identified any sanitary defect and provided adequate documentation to the executive director in the initial Level 1 assessment which established the reason that caused the first Level 1 treatment technique trigger and that the public water system corrected the problem. If the executive director has determined that a public water system is not required to conduct a Level 2 assessment based on the occurrence of a second Level 1 treatment technique trigger within a rolling 12-month period, the public water system shall still conduct the required Level 1 assessment and shall complete and submit the executive director-approved Level 1 assessment form.

§290.109(c)(3) Treatment technique assessment requirements are:

§290.109(c)(3)(A) Level 1 and Level 2 assessments are conducted in order to identify the possible presence of sanitary defects and defects in distribution system coliform monitoring practices. The assessments may also indicate that no sanitary defects were identified. When conducting assessments, systems shall ensure that the assessor evaluates minimum elements that include review and identification of inadequacies in sample sites; sampling protocol; sample processing; atypical events that could affect distributed water quality or indicate that distributed water quality was impaired; changes in distribution system maintenance and operation that could affect distributed water quality (including, but not limited to water storage); source and treatment considerations that bear on distributed water quality; and existing water quality monitoring data. The system shall conduct and complete the assessment in the format as prescribed by the executive director that tailors specific assessment elements with respect to the size and type of the system and the size, type, and characteristics of the distribution system.

§290.109(c)(3)(A)(i) Level 1 and Level 2 assessments shall be conducted and completed by the public water system, licensed operators as required under §290.46(e) of this title (relating to Minimum Acceptable Operating Practices for Public Drinking Water Systems), or other parties approved by the executive director. The public water system, licensed operators, as required under §290.46(e) of this title, and other parties approved by the executive director shall have also completed training as required in clause (iii) of this subparagraph and any additional training required by the executive director in writing, upon

notice to the public water system, licensed operators, and other parties approved by the executive director.

§290.109(c)(3)(A)(ii) Other parties approved by the executive director include, but are not limited to:

§290.109(c)(3)(A)(ii)(I) backflow prevention assembly testers and customer service inspectors licensed under Chapter 30 of this title (relating to Occupational Licenses and Registrations);

§290.109(c)(3)(A)(ii)(II) plumbing inspectors and water supply protection specialists licensed by the Texas State Board of Plumbing Examiners;

§290.109(c)(3)(A)(ii)(III) licensed professional engineers licensed by the Texas Board of Professional Engineers;

§290.109(c)(3)(A)(ii)(IV) circuit riders or technical assistance providers under contract with the executive director or other government agency as approved by the executive director; or

§290.109(c)(3)(A)(ii)(V) utility supervisor or manager supported by various utility staff or other individuals that meet the assessment requirements as described in this paragraph.

§290.109(c)(3)(A)(iii) Assessors who have conducted Level 1 assessments which were determined by the executive director to be insufficient or inadequate may be required to complete additional training or obtain certifications as prescribed by the executive director.

§290.109(c)(3)(B) The Level 1 and Level 2 assessments shall be conducted and completed consistent with all directives set forth by the executive director and with respect to the size, type, and characteristics of the public water system. When conducting assessments, at a minimum, public water systems shall ensure that the following items are evaluated:

§290.109(c)(3)(B)(i) review and identification of inadequacies in sample sites;

§290.109(c)(3)(B)(ii) sampling protocol;

§290.109(c)(3)(B)(iii) sample processing;

§290.109(c)(3)(B)(iv) atypical events that could affect distributed water quality or indicate that distributed water quality was impaired;

§290.109(c)(3)(B)(v) changes in distribution system maintenance and operation that could affect distributed water quality (including, but not limited to water storage);

§290.109(c)(3)(B)(vi) source and treatment considerations that bear on distributed water quality, where appropriate;

§290.109(c)(3)(B)(vii) existing water quality monitoring data; and

§290.109(c)(3)(B)(viii) the possible presence of sanitary defects.

§290.109(c)(3)(C) A public water system shall conduct a Level 1 assessment and complete the executive director-approved Level 1 assessment form when the public water system exceeds one of the treatment technique triggers in paragraph (1) of this subsection. The public water system must note no sanitary defects were identified or describe sanitary defects detected, corrective actions completed, and a proposed timetable for any corrective actions not already completed in the Level 1 assessment form. At the discretion of the executive director, the public water system shall comply with any additional or expedited corrective actions when there is a potential for an acute health risk.

§290.109(c)(3)(C)(i) Both the Level 1 assessment and the executive director- approved Level 1 assessment form shall be completed and the form submitted to the executive director as soon as practical, but no later than 30 days after the public water system learns that it has exceeded a trigger, or 30 days after all routine and repeat monitoring was required to be completed for the calendar month in which the system exceeded the trigger, whichever is earlier.

§290.109(c)(3)(C)(ii) If the executive director determines that the Level 1 assessment is not sufficient, the public water system shall consult with the executive director and submit a revised assessment form to the executive director within 30 days from the date of consultation.

§290.109(c)(3)(C)(iii) The executive director will determine if the public water system has identified the likely cause(s) of the trigger and, if so, was the cause(s) corrected, or has an acceptable schedule to correct the problem been included. The assessments may also indicate that no sanitary defects were identified.

§290.109(c)(3)(D) A public water system shall ensure that a Level 2 assessment and the executive director-approved Level 2 assessment form are conducted and completed consistently with all directives set forth by the executive director if the public water system exceeds one of the treatment technique triggers in paragraph (2) of this subsection. The public water system shall comply with any expedited actions or additional actions required by the executive director in the case of an E. coli MCL violation.

§290.109(c)(3)(D)(i) After any trigger in paragraph (2) of this subsection, the public water system shall ensure that both the Level 2 assessment and the executive director-approved Level 2 assessment form are completed by the public water system, licensed operators as required under §290.46(e) of this

title, or by parties approved by the executive director and the completed form submitted to the executive director as soon as practical but no later than 30 days after the public water system learns that it has exceeded a trigger in paragraph

2. of this subsection, or 30 days after all routine and repeat monitoring was required to be completed for the calendar month in which the system exceeded the trigger, whichever is earlier.

§290.109(c)(3)(D)(ii) If the executive director determines that the completed Level 2 assessment is not sufficient or the proposed timetable for any corrective actions not completed is not sufficient, the public water system shall consult with the executive director. If any revisions are required after consultation, the public water system shall submit a revised assessment form to the executive director within 30 days from the date of the consultation.

§290.109(c)(3)(D)(iii) After the Level 2 assessment is submitted, the executive director will determine if the public water system has identified the likely cause(s) of the trigger and corrected the cause(s), or has included an acceptable timetable for correcting the cause(s). The assessments may also indicate that no sanitary defects were identified.

§290.109(c)(3)(E) Public water systems must correct sanitary defects found through either Level 1 or Level 2 assessments described in this subsection. For corrective actions not completed by the time of submission of the assessment form, the public water system must complete the corrective actions in compliance with a timetable approved by the executive director in consultation with the public water system. The public water system must notify the executive director when scheduled corrective actions have been completed.

§290.109(c)(3)(F) At any time during the assessment or corrective action phase, either the public water system or the executive director may request a consultation with the other party to determine the appropriate actions. The public water system shall consult with the executive director on all relevant information that may impact its ability to comply with a requirement of this subsection.

§290.109(d) Monitoring requirements for microbial contaminants. Public water systems shall collect samples for total coliform, fecal coliform, E. coli (or other approved fecal indicator) at sampling sites and a sample collection schedule, as designated by the public water system, which are subject to review and revision as directed by the executive director. All compliance samples must be collected at sampling sites and a sample collection schedule that are representative of water throughout the distribution system and shall be reflected in the public water system’s Sample Siting Plan and included with the public water system’s monitoring plan in accordance with §290.121 of this title (relating to Monitoring Plans). All public water systems shall develop a written Sample Siting Plan as described in paragraph (6) of this subsection.

§290.109(d)(1) Routine microbial sampling locations. Public water systems shall routinely monitor for microbial contaminants at the following locations.

§290.109(d)(1)(A) Public water systems must collect routine distribution coliform samples at a customer’s premise, dedicated sampling station, or other designated compliance sampling location at active service connections which are representative of water quality throughout the distribution system. Other sampling sites may be used if located adjacent to active service connections.

§290.109(d)(1)(B) Public water systems shall collect distribution coliform samples at locations specified in the public water system’s Sample Siting Plan which shall be included in the public water system’s monitoring plan.

§290.109(d)(2) Routine distribution coliform sampling frequency. All public water systems must sample for distribution coliform at the following frequency.

§290.109(d)(2)(A) Community and noncommunity public water systems must collect routine distribution coliform samples at a frequency based on the population served by the system.

§290.109(d)(2)(A)(i) The population for noncommunity systems will be based on the maximum number of persons served on any given day during the month based on the data reported by the public water system to the executive director during the most recent sanitary survey of the public water system or any other data as required by the executive director.

§290.109(d)(2)(A)(ii) The population of community systems will be based on the data reported by the public water system to the executive director during the most recent sanitary survey of the public water system or any other data as required by the executive director.

§290.109(d)(2)(A)(iii) The minimum sampling frequency for public water systems is shown in the following table.

Table 9: §290.109(d)(2)(A)(iii)

§290.109(d)(2)(B) A public water system which uses surface water or groundwater under the direct influence of surface water must collect routine distribution coliform samples at regular time intervals throughout the month.

§290.109(d)(2)(C) A public water system which uses only purchased water or groundwater not under the direct influence of surface water and serves more than 4,900 persons must collect routine distribution coliform samples at regular time intervals throughout the month.

§290.109(d)(2)(D) A public water system which uses only purchased water or groundwater not under the direct influence of surface water and serves 4,900 persons or fewer may collect all required routine distribution coliform samples on a single day if they are taken from different sites.

§290.109(d)(2)(E) A total coliform-positive sample invalidated under this subsection does not count towards meeting the minimum routine monitoring requirements of this subsection. Unless the executive director has invalidated the sample in accordance with subsection (e) of this section, all routine coliform sample

results must be used to determine compliance with subsection (b)(1) of this section and to determine treatment technique trigger and assessment requirements as described in subsection (c)(1) and (2) of this section.

§290.109(d)(2)(F) All public water system shall collect at least the minimum number of required routine microbial samples even if the public water system has had an E. coli MCL violation under any of the conditions as described in subsection (b)(1)(A) - (D) of this section or has exceeded the coliform treatment technique triggers as described in subsection (c)(1) and (2) of this section.

§290.109(d)(2)(G) A public water system may conduct more microbial compliance monitoring than is required by this subsection to investigate potential problems in the public water system treatment facilities and distribution system and use monitoring to assist in identifying problems. A public water system may collect more than the minimum number of required routine samples required by this subsection. A public water system that collects more than the minimum number of required routine samples required by this subsection shall include the results of these samples in calculating whether the coliform treatment technique triggers as described in subsection (c)(1) and (2) of this section have been exceeded. The additional routine sample sites shall be included in the public water system’s Sample Siting Plan and collected in accordance with the Sample Siting Plan and shall be representative of water throughout the distribution system.

§290.109(d)(3) Repeat distribution coliform sampling requirements. Public water systems shall conduct repeat monitoring if one or more of the routine samples is found to contain coliform organisms.

§290.109(d)(3)(A) If a routine distribution coliform sample is coliform-positive, the public water system must collect a set of repeat distribution coliform samples within 24 hours of being notified of the positive result, or as soon as possible if the local laboratory is closed. The executive director may extend the 24-hour limit on a case-by-case basis if the public water system has a logistical problem in collecting the repeat samples within 24 hours that is beyond the public water system’s control. All public water systems shall collect no fewer than three repeat samples for each total coliform-positive sample found even if the public water system has had an E. coli MCL violation under any of the conditions as described in subsection (b)(1)(A) - (D) of this section or has exceeded the coliform treatment technique triggers as described in subsection (c)(1) and (2) of this section.

§290.109(d)(3)(B) The public water system must collect all repeat samples on the same day, except a public water system with a single service connection may collect daily repeat samples over a three-day period until the required number of repeat samples has been collected.

§290.109(d)(3)(C) Unless the public water system meets the provisions of clause

1. or (ii) of this subparagraph, the public water system must collect at least one repeat sample from the sampling tap where the original coliform-positive sample was taken,

and at least one repeat sample at a tap within five service connections upstream and at least one repeat sample at a tap within five service connections downstream of the original sampling site. If the positive routine sample was collected at the end of the distribution system, or one service connection away from the end of the distribution system, one repeat sample must be collected at that point and the other two repeat samples must be collected within five connections upstream of that point.

§290.109(d)(3)(C)(i) As approved by the executive director, public water systems may propose repeat monitoring locations to the executive director that the public water system considers to be representative of a pathway for contamination of the distribution system. A public water system may elect to specify either alternative fixed locations or criteria for selecting repeat sampling sites on a situational basis in a written standard operating procedure (SOP) in its Sample Siting Plan. The public water system shall design its SOP to focus the repeat samples at locations that best verify and determine the extent of potential contamination of the distribution system area based on specific situations. The executive director may modify the SOP or require alternative monitoring locations as needed.

§290.109(d)(3)(C)(ii) As approved by the executive director, groundwater public water systems serving 1,000 or fewer people may propose repeat sampling locations to the executive director, in a written SOP in its Sample Siting Plan, that differentiate potential source water and distribution system contamination (e.g., by sampling at entry points to the distribution system). A groundwater public water system with a single well required to conduct triggered source water monitoring may, with written executive director approval, take one of its repeat samples at the monitoring location required for triggered source water monitoring under paragraph (4) and (4)(A) of this subsection if the public water system demonstrates to the executive director that the Sample Siting Plan remains representative of water quality in the distribution system. If approved by the executive director, the public water system may use that sample result to meet the monitoring requirements for both repeat monitoring under this paragraph and triggered source monitoring under paragraph (4) and (4)(A) of this subsection.

§290.109(d)(3)(C)(iii) All public water systems shall include all sample sites as required by this subparagraph and any required SOPs for any proposed sampling sites as described in clauses (i) and (ii) of this subparagraph in the public water system’s Sample Siting Plan in accordance with paragraph (6) of this subsection.

§290.109(d)(3)(D) If one or more repeat samples in the set is total coliform- positive, the public water system must collect an additional set of repeat samples in the manner specified in subparagraphs (A) - (C) of this paragraph. The additional samples must be collected within 24 hours of the public water system being notified of the positive result or as soon as possible if the local laboratory is closed. The executive

director may extend the 24-hour limit on a case-by-case basis if the public water system has a logistical problem in collecting the repeat samples within 24 hours that is beyond the public water system’s control. In accordance with 40 Code of Federal Regulations (CFR) §141.858(a)(1) the executive director is prohibited from waiving the requirement for a public water system to collect repeat samples as specified in subparagraphs (A) - (D) of this paragraph. The public water system must repeat this process until either one of the following occurs:

§290.109(d)(3)(D)(i) total coliforms are not detected in one complete set of repeat samples;

§290.109(d)(3)(D)(ii) a coliform treatment technique trigger as described in subsection (c)(1) and (2) of this section has been exceeded; or

§290.109(d)(3)(D)(iii) If a treatment technique trigger as described in subsection (c)(1) and (2) of this section is exceeded as a result of a routine sample being total coliform-positive, public water systems are required to conduct only one round of repeat monitoring for each total coliform-positive routine sample.

§290.109(d)(3)(E) After a public water system collects a routine sample and before it learns the results of the analysis of that sample, if it collects another routine sample(s) from within five adjacent service connections of the initial sample, and the initial sample is found to contain total coliform bacteria, then the public water system may count the subsequent sample(s) as a repeat sample instead of as a routine sample.

§290.109(d)(3)(F) A total coliform-positive sample invalidated under this subsection does not count towards meeting the minimum repeat monitoring requirements of this subsection. Unless the executive director has invalidated the sample in accordance with subsection (e) of this section, all repeat coliform sample results must be used to determine compliance with subsection (b)(1) of this section and to determine treatment technique trigger and assessment requirements as described in subsection (c)(1) and (2) of this section.

§290.109(d)(4) General requirements for raw groundwater source monitoring. Groundwater systems must comply, unless otherwise noted, with the requirements of this section. Any raw groundwater source sample required under this paragraph must be collected at a location prior to any treatment of the groundwater source and use analytical procedures and methods described in §290.119(b)(10) of this title (relating to Analytical Procedures). The public water system may collect a sample at an executive director-approved location prior to any treatment to meet the requirements of this paragraph and subparagraph (A) of this paragraph if the sample is representative of the water quality of that well.

§290.109(d)(4)(A) Triggered source monitoring general requirements. A groundwater system must conduct triggered source water monitoring for E. coli (or other approved fecal indicator), if both of the following conditions exist.

§290.109(d)(4)(A)(i) The system does not provide at least 4-log treatment of viruses (as defined in §290.103(44) of this title (relating to Definitions)) before the first customer for each groundwater source; and

§290.109(d)(4)(A)(ii) The system is notified that a routine distribution coliform sample is positive and the sample is not invalidated under subsection (e)(1) of this section.

§290.109(d)(4)(B) Triggered source monitoring sampling requirements. A groundwater system must collect, within 24 hours of notification of the routine distribution total coliform-positive sample, at least one raw groundwater source E. coli (or other approved fecal indicator) sample from each groundwater source in use at the time the distribution coliform-positive sample was collected.

§290.109(d)(4)(B)(i) The executive director may extend the 24-hour time limit on a case-by-case basis if the system cannot collect the raw groundwater source sample within 24 hours due to circumstances beyond its control. If the executive director extends the 24-hour time limit on a case-by-case basis, the public water system must collect the sample within 48 hours.

§290.109(d)(4)(B)(ii) If approved by the executive director and documented in the public water system’s monitoring plan, public water systems with more than one groundwater source may be allowed to sample a representative groundwater source or sources. Public water systems shall modify their current monitoring plan to identify one or more groundwater sources that are representative of each distribution coliform sampling site and is intended to be used for representative source sampling.

§290.109(d)(4)(B)(iii) A groundwater system with one well serving 1,000 people or fewer may use one of the three required repeat samples collected from a raw groundwater source to meet both the repeat requirements of paragraph (3) of this subsection and the triggered raw source monitoring requirements in this paragraph when all of the following requirements are met:

§290.109(d)(4)(B)(iii)(I) the fecal indicator used is E. coli;

§290.109(d)(4)(B)(iii)(II) the executive director has provided written approval for the public water system to meet the monitoring requirements for both repeat monitoring under paragraph (3) of this subsection and triggered source monitoring under this paragraph and subparagraph (A) of this paragraph; and

§290.109(d)(4)(B)(iii)(III) the public water system’s sample siting plan remains representative of water quality in the distribution system. If a required repeat sample is used to meet both requirements and found to be E. coli-positive, the public water system will have achieved an E. coli MCL as defined in subsection (b)(1)(A) - (D) of this section and corrective action will be required for the groundwater source where the sample was found to be E. coli-positive.

§290.109(d)(4)(B)(iv) If the executive director does not require corrective action under §290.116 of this title (relating to Groundwater Corrective Actions and Treatment Techniques) for a fecal indicator positive source water sample collected under this subparagraph that is not invalidated under subsection (e) of this section, the public water system shall collect five additional source water samples from the same source within 24 hours of being notified of the fecal indicator positive sample.

§290.109(d)(4)(B)(v) If a public water system takes more than one repeat sample at the monitoring location required for triggered source water monitoring, the public water system may reduce the number of additional source water samples required under clause (iv) of this subparagraph by the number of repeat samples taken at that location that were not E. coli-positive.

§290.109(d)(4)(C) Consecutive and wholesale systems. Consecutive groundwater systems receiving drinking water from a wholesaler must notify the wholesale system(s) within 24 hours of being notified of the positive coliform distribution sample. The wholesale groundwater system(s) must comply with the following:

§290.109(d)(4)(C)(i) A wholesale groundwater system that receives notice of a distribution coliform sample positive from a consecutive system it serves must collect a sample from each of its groundwater sources within 24 hours of the notification and analyze each sample for the presence of E. coli (or other approved fecal indicator).

§290.109(d)(4)(C)(ii) If any raw source sample is E. coli (or other approved fecal indicator) positive, the wholesale groundwater system must notify all consecutive systems served by that groundwater source of the fecal indicator positive within 24 hours of being notified. The wholesale system and all consecutive systems served by that groundwater source must notify their water system customers in accordance with subsection (h)(2) of this section and shall meet the requirements of subparagraph (B)(iv) of this paragraph.

§290.109(d)(4)(C)(iii) If any raw source sample is E. coli-positive, the wholesale groundwater system shall notify all consecutive systems served by that groundwater source of the fecal indicator source water positive within 24 hours of being notified and shall meet the requirements of subparagraph (B)(iv) of this paragraph.

§290.109(d)(4)(D) Exceptions to the triggered source monitoring requirements. A groundwater system is not required to comply with the triggered source monitoring requirements if any of the following conditions exist.

§290.109(d)(4)(D)(i) The executive director determines and documents in writing, that the distribution coliform-positive sample is caused by a distribution system deficiency; or

§290.109(d)(4)(D)(ii) The distribution coliform-positive sample is collected at a location that meets the distribution coliform sample invalidation criteria as specified in subsection (e)(1) of this section and the replacement sample is negative for coliforms.

§290.109(d)(4)(E) Assessment source monitoring. The executive director may require monthly source assessment raw monitoring without the presence of a positive total coliform distribution sample if well conditions exist that indicate the groundwater may be susceptible to fecal contamination. The executive director may conduct a hydrogeological sensitivity assessment to determine if the source is susceptible to fecal contamination. If requested by the executive director, groundwater systems must provide the executive director with any existing information that will enable the executive director to perform a hydrogeological sensitivity assessment. A groundwater system conducting assessment source monitoring may use a triggered source sample collected under subparagraph (A) of this paragraph to meet the assessment source monitoring requirement. A groundwater system with a groundwater source sample collected under this subparagraph or under subparagraph (A) of this paragraph that is fecal indicator positive and that is not invalidated under subsection (e)(2) of this section, including consecutive systems served by the groundwater source, shall conduct public notification under §290.122(a) of this title (relating to Public Notification). Additionally, an assessment source monitoring sample may be used as a triggered source monitoring sample if collected within 24 hours of notification of the coliform- positive distribution sample. Assessment source monitoring requirements may include:

§290.109(d)(4)(E)(i) Source monitoring, collected in a manner described in §290.119(b)(10) of this title, for a period of 12 months that represents each month that the system provides groundwater to the public from the raw groundwater source or such time period as specified by the executive director.

§290.109(d)(4)(E)(ii) Collection of samples from each well unless the system has an approved triggered source monitoring plan under subparagraph (B)(ii) of this paragraph.

§290.109(d)(5) Culture analysis. If any routine or repeat sample is total coliform- positive, that total coliform-positive medium will be analyzed to determine if E. coli are present. If E. coli are present, the public water system shall notify the executive director by the end of the day in accordance with subsection (h) of this section.

§290.109(d)(6) Sample Siting Plan requirements. All public water systems shall develop and complete a written Sample Siting Plan as described in this paragraph that identifies routine and repeat microbial sampling sites and a sample collection schedule as required by this subsection that are representative of water throughout the distribution system. The Sample Siting Plan shall include all groundwater sources and any associated sampling points necessary to meet the requirements of this subsection. The Sample Siting Plan shall be included as a part of the public water system’s monitoring plan as described in §290.121 of this title. Sample Siting Plans shall be completed in a format specified by the executive director and are subject to review and revision by the executive director.

§290.109(d)(6)(A) All public water systems shall collect routine and repeat samples according to a written Sample Siting Plan. All routine and repeat sample site locations, any required SOP, and any sampling point locations necessary to meet the requirements of this subsection shall be reflected in the written Sample Siting Plan. For community and noncommunity public water systems serving 1,000 or fewer people using only groundwater, the executive director shall evaluate during every sanitary survey (on-site inspection) the water system factors (including but not limited to pertinent water quality, compliance history, distribution system, all the components of a sanitary survey and its findings) to ensure the timeframe during the month, locations, and number of microbial compliance monitoring sample sites are adequate for producing and distributing safe drinking water.

§290.109(d)(6)(B) All public water systems shall include any required SOP for any proposed repeat sampling sites as described in paragraph (3)(C) of this subsection in the Sample Siting Plan. As required by the executive director, the executive director may review, revise, and approve any repeat sampling proposed by public water systems under paragraph (3)(C) of this subsection.

§290.109(d)(6)(C) The Sample Siting Plan shall include a distribution system map or series of maps which identifies distribution system valves and mains as described in §290.46(n)(2) of this title. The distribution system map shall also include the location of all routine microbial sample sites, water main sizes, entry point source locations, water storage facilities, and any pressure plane boundaries.

§290.109(d)(6)(D) All public water systems shall update their written Sample Siting Plan and map as necessary, or as requested by the executive director, to identify the most current microbial routine and repeat sampling sites and a sample collection schedule that are representative of water throughout the public water system’s distribution system.

§290.109(d)(6)(E) All public water systems shall maintain a copy of their updated Sample Siting Plan and map on-site at the public water system for inspection purposes and at the request of the executive director, provide a copy of their Sample Siting Plan and/or map to the executive director for review and/or revision purposes.

§290.109(e) Analytical and invalidation requirements for microbial contaminants. Analytical procedures shall be performed in accordance with §290.119 of this title. Testing for microbial contaminants shall be performed at a laboratory certified by the executive director. The public water system must use a certified laboratory certified for each method and associated contaminant(s) for compliance analyses in accordance with §290.119 of this title.

§290.109(e)(1) Distribution coliform sample invalidation. The executive director may invalidate a distribution total coliform-positive sample if one of the following conditions is met.

§290.109(e)(1)(A) The executive director may invalidate a sample if the laboratory provides written notice that improper sample analysis caused the total coliform- positive result.

§290.109(e)(1)(B) The executive director may invalidate a sample if the results of repeat samples collected, as required by this section, determine that the total coliform-positive sample resulted from a domestic or other non-distribution system plumbing problem. The executive director cannot invalidate a sample on the basis of repeat sample results unless all repeat sample(s) collected at the same tap as the original total coliform-positive sample are also total coliform-positive, and all repeat samples collected within five service connections of the original tap are total coliform- negative. Under those circumstances, the system may request that the executive director invalidate the sample. The system must provide copies of the routine positive and all repeat samples. The executive director may not invalidate a total coliform- positive sample solely on the grounds that all repeat samples are total coliform- negative or if the system has only one service connection.

§290.109(e)(1)(C) The executive director may invalidate a sample if there are substantial grounds to believe that the total coliform-positive result is due to a circumstance or condition which does not reflect water quality in the distribution system. In this case, the system must still collect all repeat samples required by this section, and use them to determine compliance with the E. coli MCL as described in subsection (g) of this section and whether a coliform treatment technique trigger has been exceeded as described in subsection (c) of this section. The system must provide written documentation which must state the specific cause of the total coliform- positive sample, and the action the system has taken, or will take, to correct this problem. The system must obtain the written and signed approval from the executive director before the sample can be invalidated under this condition. The executive director may not invalidate a total coliform-positive sample solely on the grounds that all repeat samples are total coliform-negative.

§290.109(e)(1)(D) The executive director may invalidate a sample if the laboratory provides written notice that the sample was unsuitable for analysis and the laboratory invalidated the sample based on the requirements of 40 CFR §141.853(c)(2). When the sample is invalidated under this condition, the system must collect another sample from the same location as the original sample within 24 hours of being

notified, and have it analyzed for the presence of total coliforms. The system must continue to re-sample within 24 hours and have the samples analyzed until it obtains a valid result. The executive director may waive the 24-hour time limit on a case-by- case basis. Alternatively, the executive director may implement criteria for waiving the 24-hour sampling time limit to use in lieu of case-by-case extension.

§290.109(e)(1)(E) If a sample is invalidated by the laboratory, the public water system must collect another sample from the same location as the original sample within 24 hours of being notified, or as soon as possible if the laboratory is closed, and have it analyzed for the presence of total coliform. The system must continue to resample within 24 hours and have the samples analyzed until it obtains a valid result.

§290.109(e)(2) A groundwater system may obtain invalidation of a fecal indicator positive groundwater source sample if the conditions of subparagraphs (A) and (B) of this paragraph apply. If the executive director invalidates a fecal indicator positive groundwater source sample, the system must collect another source sample as specified in subsection (d)(4) of this section within 24 hours of being notified of the invalidation.

§290.109(e)(2)(A) Notice from the laboratory must document that improper sample analysis occurred. If a laboratory invalidates a sample, the system must collect another sample from the same location as the original sample within 24 hours of being notified of the invalidated sample, and have it analyzed for the presence of E. coli (or other approved fecal indicator). The public water system must continue to re- sample within 24 hours and have the samples analyzed until it obtains a valid result. If approved by the executive director, the 24-hour time limit may be extended.

§290.109(e)(2)(B) The executive director may invalidate the sample if the public water system provides written documentation that there is substantial evidence that a fecal indicator positive groundwater source sample is not related to source water quality. If the executive director invalidates a sample, the public water system must collect another sample from the same location as the original sample within 24 hours of being notified of the invalidated sample, and have it analyzed for the presence of E. coli (or other approved fecal indicator).

§290.109(e)(3) Culture analysis. If any distribution system coliform sample is total coliform-positive, that total coliform-positive medium will be analyzed to determine if E. coli are present. If E. coli are present, the public water system shall notify the executive director by the end of the day in accordance with subsection (h) of this section. If any raw groundwater source sample is used to meet the repeat requirements of subsection (d)(3)(C)(ii) and (4)(B)(iii) then it must be analyzed to determine if E. coli are present.

§290.109(f) Reporting requirements for microbial contaminants. The owner or operator of a public water system must ensure the executive director is provided with a copy of the results of any test, measurement, or analysis required by this subsection. The copies must be submitted within the first ten days following the month in which the result is received by the public water system, or the first ten days following the end of the required monitoring period as

provided by this subsection, whichever occurs first. The copies must be mailed to the Water Supply Division, MC 155, Texas Commission on Environmental Quality, P.O. Box 13087, Austin, Texas 78711-3087.

§290.109(g) Compliance determination for microbial contaminants. Compliance with the requirements of this section shall be determined using the following criteria each month that the system is in operation.

§290.109(g)(1) A public water system commits an E. coli MCL violation if any of the following conditions occur:

§290.109(g)(1)(A) The public water system has an E. coli-positive repeat samples following a total coliform-positive routine sample;

§290.109(g)(1)(B) The public water system has a total coliform-positive repeat sample following an E. coli-positive routine sample;

§290.109(g)(1)(C) The public water system fails to take all required repeat samples following an E. coli-positive routine sample; or

§290.109(g)(1)(D) The public water system fails to test for E. coli when any repeat sample tests positive for total coliform.

§290.109(g)(2) If all repeat samples taken for triggered source water monitoring are E. coli-negative and a repeat sample taken at a monitoring location other than the one required for triggered source water monitoring is E. coli-positive, the public water system has violated the E. coli MCL, but is not required to comply with subsection (d)(4)(B)(iv) of this section. If a public water system takes more than one repeat sample at the monitoring location required for triggered source water monitoring under subsection (d)(4) of this section, and more than one repeat sample is E. coli-positive, the public water system has violated the E. coli MCL and shall also comply with the treatment technique and corrective action requirements as described in §290.116 of this title.

§290.109(g)(3) A public groundwater system that is required to collect raw source samples is required to conduct corrective action as described in §290.116 of this title and is required to provide public notification in accordance with §290.122(a) of this title if a source sample is confirmed positive for E. coli or other approved fecal indicator.

§290.109(g)(4) A public water system that fails to collect every required routine sample in a compliance period and/or to submit the analytical results to the executive director commits a monitoring violation.

§290.109(g)(5) A public water system that fails to analyze for E. coli following a total coliform-positive routine sample commits a monitoring violation.

§290.109(g)(6) A public water system that fails to monitor in accordance with the requirements of subsection (d)(4) of this section commits a monitoring violation and must provide public notification in accordance with §290.122 of this title.

§290.109(g)(7) A public water system that fails to report the results of the monitoring tests required by this section commits a reporting violation.

§290.109(g)(8) A public water system that fails to do a required public notice or certify that notification has been performed commits a public notice reporting violation.

§290.109(g)(9) The results of all routine and repeat distribution coliform samples or groundwater source samples not invalidated by the executive director shall be included in determining compliance with the E. coli MCL as described in paragraph (1)(A) - (D) of this subsection and whether a coliform treatment technique trigger has been exceeded as described in subsection (c) of this section.

§290.109(g)(10) The results of all routine and repeat distribution coliform samples or groundwater source samples invalidated by the executive director shall not be included in determining compliance with the E. coli MCL as described in paragraph (1)(A) - (D) of this subsection and whether a coliform treatment technique trigger has been exceeded as described in subsection (c) of this section.

§290.109(g)(11) Special purpose samples, such as those taken to determine whether disinfection practices are sufficient following pipe placement, replacement, or repair, shall not be used to determine compliance with the MCL for microbiological contaminants. Special purpose samples shall not be used to determine whether the coliform treatment technique trigger has been exceeded as described in subsection (c) of this section. Coliform samples taken in accordance with subsection (d)(3) of this section and that are not invalidated under subsection (e) of this section are not considered special purpose samples.

§290.109(g)(12) All seasonal public water systems shall complete executive director- approved start-up procedures and certification and maintain a copy of the start-up procedures and certification on-site at the public water system for inspection purposes. A seasonal system must certify, prior to serving water to the public, that it has complied with the executive director-approved start-up procedures. At the executive director’s request, seasonal public water systems shall submit a copy of the start-up procedures and certification to the executive director for review purposes. Failure by a seasonal public water system to complete executive director-approved start-up procedures prior to serving water to the public is a treatment technique violation. Failure by a seasonal public water system to maintain or submit certification of completion of executive director-approved start-up procedures is a reporting violation.

§290.109(g)(13) A public water system commits a treatment technique violation when a seasonal public water system fails to complete an executive director-approved start-up procedure prior to serving water to the public.

§290.109(g)(14) A public water system commits a treatment technique violation when a public water system exceeds a treatment technique trigger specified in subsection (c) of this section and then fails to conduct the required assessment or corrective actions within the timeframe specified in subsection (c) of this section.

§290.109(g)(15) A public water system required to conduct an assessment under the provisions of subsection (c) of this section shall submit the assessment report to the executive director within 30 days. The public water system shall notify the executive director in accordance with subsection (c) of this section when scheduled corrective actions are complete and for corrective actions not completed by the time of submission of the assessment form. For corrective actions not completed by the time of submission of the assessment form to the executive director, the public water system shall complete corrective actions in compliance with a timetable approved by the executive director in consultation with the public water system. The assessment may also indicate that no sanitary defects were identified.

§290.109(g)(16) A public water system that fails to notify the executive director before the end of the day in accordance with subsection (h)(3) of this section commits a reporting violation.

§290.109(h) Public notification for microbial contaminants. A public water system that is out of compliance with the requirements described in this section must notify the public using the procedures described in §290.122 of this title for microbial contamination.

§290.109(h)(1) A public water system that commits an acute MCL violation for microbial contaminants must notify the public water system customers in accordance with the boil water notice requirements of §290.46(q) of this title and the public notice requirements of §290.122(a) of this title.

§290.109(h)(2) A public groundwater system that receives an E. coli (or other approved fecal indicator) positive source sample that has not been invalidated by the executive director, or a notice of an E. coli (or other approved fecal indicator) positive source sample from a wholesale system, including consecutive systems, must notify the public water system customers within 24-hours in accordance with the requirements of §290.122(a) of this title and include notice in the next Consumer Confidence Report for community public water systems or provide as a special notice for noncommunity systems in accordance with §290.272(g)(7) of this title (relating to Content of the Report) for community public water systems and §290.116(f)(2) of this title for noncommunity public water systems. Consecutive systems must issue public notice in accordance with §290.122(g) of this title. The public water system must continue to notify the public annually until the fecal contamination in the source water is determined by the executive director to be corrected as specified under §290.116 of this title.

§290.109(h)(3) A public water system that has E. coli (or other approved fecal indicator) present must notify the executive director by the end of the day when the public water system is notified of the test result.

§290.109(h)(4) A public water system which commits an MCL violation must report the violation to the executive director immediately after it learns of the violation, but no later than the end of the next business day, and notify the public in accordance with §290.122(b) of this title.

§290.109(h)(5) A public water system which commits an E. coli MCL violation shall report the violation to the executive director immediately after it learns of the violation, but no later than the end of the day, and notify the public in accordance with §290.122(a) of this title.

§290.109(h)(6) A public water system which has failed to comply with a coliform monitoring requirement must report the monitoring violation to the executive director within ten days after the system discovers the violation and notify the public in accordance with §290.122(c) of this title.

§290.109(h)(7) A public water system that has committed a treatment technique trigger and assessment requirement for coliforms in subsection (c)(1) and (2) of this section and commits a treatment technique violation as described in subsection (g)(15) of this section shall report the violation to the executive director no later than the end of the next business day after it learns of the violation, and notify the public in accordance with §290.122(b) of this title.

§290.109(h)(8) A public water system that commits a treatment technique violation for failure to complete and certify seasonal system start-up procedures as described in subsection (g)(10) and (11) of this section shall report the violation to the executive director no later than the end of the next business day after it learns of the violation, and notify the public in accordance with §290.122(b) of this title. In the notification in accordance with §290.122(b) of this title, if a seasonal system fails to monitor for total coliforms or E. coli prior to serving water to the public, it must include the following language: We are required to monitor your drinking water for specific contaminants on a regular basis. Results of regular monitoring are an indicator of whether or not your drinking water meets health standards. During {COMPLIANCE PERIOD}, we “did not monitor or test” or “did not complete all monitoring or testing” for {CONTAMINANT(S)}, and therefore cannot be sure of the quality of your drinking water during that time.

§290.109(i) The executive director, pursuant to 40 CFR §141.63(e), recognizes the following as the best technology, treatment techniques, or other means available for achieving compliance with the MCL for E. coli as described in subsection (b)(1)(A) - (D) of this section as follows:

§290.109(i)(1) protection of wells from fecal contamination by appropriate placement and construction;

§290.109(i)(2) maintenance of a disinfectant residual throughout the distribution system;

§290.109(i)(3) proper maintenance of the distribution system including appropriate pipe replacement and repair procedures, main flushing programs, proper operation and maintenance of storage tanks and reservoirs, cross-connection control, and continual maintenance of positive water pressure in all parts of the distribution system;

§290.109(i)(4) filtration and disinfection of surface water, as described in this chapter, or disinfection of groundwater, as described in chapter, using strong oxidants such as chlorine, chlorine dioxide, or ozone;

§290.109(i)(5) for systems using groundwater, development and implementation of a Wellhead Protection Program, as directed by the executive director, and in accordance with the federal Safe Drinking Water Act, United States Code, §1428; or

§290.109(i)(6) the executive director may require additional best technology, treatment techniques, or other means available for achieving compliance with the MCL for E. coli as described in subsection (g)(1) of this section.

Source Note: The provisions of this §290.109 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective November 8, 2012, 37 TexReg 8849; amended to be effective September 12, 2013, 38 TexReg 5880; amended to be effective March 30, 2017, 42 TexReg 1466

§290.110. Disinfectant Residuals

§290.110(a) Applicability. All public water systems shall properly disinfect water before it is distributed to any customer and shall maintain acceptable disinfectant residuals within the distribution system.

§290.110(b) Minimum and maximum acceptable disinfectant concentrations. All public water systems shall provide the minimum levels of disinfectants in accordance with the provisions of this section. Public water systems shall not exceed the maximum residual disinfectant levels (MRDLs) provided in this section.

§290.110(b)(1) The disinfection process used by public water systems must ensure that water has been adequately disinfected before it enters the distribution system.

§290.110(b)(1)(A) The disinfection process used by public water systems treating surface water sources or groundwater sources that are under the direct influence of surface water must meet the requirements of §290.111(d) of this title (relating to Surface Water Treatment).

§290.110(b)(1)(B) The executive director may require the disinfection process used by public water systems treating groundwater sources that are not under the direct influence of surface water to meet the requirements of §290.116 of this title (relating to Groundwater Corrective Actions and Treatment Techniques).

§290.110(b)(1)(C) The disinfection process at other types of treatment plants shall provide the level of disinfection required by the executive director.

§290.110(b)(2) The residual disinfectant concentration in the water entering the distribution system shall be at least 0.2 milligram per liter (mg/L) free chlorine or 0.5 mg/L chloramine (measured as total chlorine).

§290.110(b)(3) The chlorine dioxide residual of the water entering the distribution system shall not exceed an MRDL of 0.8 mg/L.

§290.110(b)(4) The residual disinfectant concentration in the water within the distribution system shall be at least 0.2 mg/L free chlorine or 0.5 mg/L chloramine (measured as total chlorine).

§290.110(b)(5) The running annual average of the free chlorine or chloramine residual (measured as total chlorine) of the water within the distribution system shall not exceed an MRDL of 4.0 mg/L.

§290.110(c) Monitoring requirements. All public water systems shall monitor the performance of the disinfection facilities to ensure that appropriate disinfectant levels are maintained. All monitoring conducted pursuant to the requirements of this section must be conducted at sites designated in the public water system’s monitoring plan.

§290.110(c)(1) Entry point compliance monitoring for surface water and groundwater under the direct influence of surface water. Public water systems that treat surface water or groundwater under the direct influence of surface water must verify that they meet the disinfection requirements of subsection (b)(2) of this section.

§290.110(c)(1)(A) Public water systems that treat surface water or groundwater under the direct influence of surface water and sell treated water on a wholesale basis or serve more than 3,300 people must continuously monitor and record the disinfectant residual of the water at each entry point. If there is a failure in the continuous monitoring equipment, grab sampling every four hours may be conducted in lieu of continuous monitoring, but for no more than five working days following the failure of the equipment.

§290.110(c)(1)(B) Public water systems that treat surface water or groundwater under the direct influence of surface water, serve 3,300 or fewer people and do not sell treated water on a wholesale basis must monitor and record the disinfectant residual of the water at each entry point with either continuous monitors or grab samples.

§290.110(c)(1)(B)(i) If a system uses grab samples, the samples must be collected on an ongoing basis at the frequency prescribed in the following table.

Table 10: §290.110(c)(1)(B)(i) Entry Point Disinfectant Residual Monitoring Frequency for Grab Samples

§290.110(c)(1)(B)(ii) The grab samples cannot be taken at the same time and the sampling interval is subject to the executive director’s review and approval.

§290.110(c)(1)(B)(iii) Treatment plants that use grab samples and fail to detect an appropriate disinfectant residual must repeat the test at four-hour or shorter intervals until compliance has been reestablished.

§290.110(c)(1)(C) Continuous monitors must record the disinfectant residual of the water every 30 minutes.

§290.110(c)(2) Entry point compliance monitoring for groundwater and purchased water. Public water systems that treat groundwater or that purchase and resell treated water must, upon the request of the executive director, verify that they meet the disinfection requirements of subsection (b)(2) of this section.

§290.110(c)(2)(A) A public water system that uses free chlorine must measure free chlorine.

§290.110(c)(2)(B) A public water system that has a chloramine residual must measure total chlorine.

§290.110(c)(3) Chlorine dioxide compliance monitoring. Each treatment plant using chlorine dioxide must monitor and record the chlorine dioxide residual of the water entering the distribution system at least once each day. If the chlorine dioxide residual in the water entering the distribution system exceeds the MRDL contained in subsection (b)(3) of this section, the treatment plant must conduct additional tests.

§290.110(c)(3)(A) If the public water system does not have additional chlorination facilities in the distribution system, it must conduct three additional tests at the service connection nearest the treatment plant where an elevated chlorine dioxide residual was detected. The first additional test must be conducted within two hours after detecting an elevated chlorine dioxide residual at the entry point to the distribution system. The two subsequent tests must be conducted at six-hour to eight- hour intervals thereafter.

§290.110(c)(3)(B) If the public water system has additional chlorination facilities in the distribution system, it must conduct an additional test at the service connection nearest the treatment plant where an elevated chlorine dioxide residual was detected, an additional test at the first service connection after the point where the water is rechlorinated, and an additional test at a location in the far reaches of the distribution system. The additional test at the location nearest the treatment plant must be conducted within two hours after detecting an elevated chlorine dioxide residual at the entry point to the distribution system. The two other tests must be conducted at six-hour to eight-hour intervals thereafter.

§290.110(c)(4) Distribution system compliance monitoring. All public water systems shall monitor the disinfectant residual at various locations throughout the distribution system.

§290.110(c)(4)(A) Public water systems that use groundwater or purchased water sources only and serve fewer than 250 connections and fewer than 750 people daily, must monitor the disinfectant residual at representative locations in the distribution system at least once every seven days.

§290.110(c)(4)(B) Public water systems that serve at least 250 connections or at least 750 people daily, and use only groundwater or purchased water sources must monitor the disinfectant residual at representative locations in the distribution system at least once per day.

§290.110(c)(4)(C) Public water systems using surface water sources or groundwater under the direct influence of surface water must monitor the

disinfectant residual tests at least once per day at representative locations in the distribution system.

§290.110(c)(4)(D) All public water systems must monitor the residual disinfectant concentration at the same time and at the same sampling site a bacteriological sample is collected, as specified in §290.109 of this title (relating to Microbial Contaminants) in addition to the residual disinfectant concentration monitoring requirements as described in this subsection and chapter.

§290.110(c)(4)(E) All public water systems with a chloramine residual must monitor the total chlorine residual downstream of any chlorine and ammonia injection points, in conjunction with the chloramine effectiveness sampling in paragraph (5)(C) of this subsection, in the distribution system weekly and whenever the chemical dose is changed.

§290.110(c)(5) Chloramine effectiveness sampling. Public water systems with a chloramine residual shall monitor to ensure that monochloramine is the prevailing chloramine species and that nitrification is controlled. Sample sites and procedures used for chloramine effectiveness sampling must be documented in the system’s nitrification action plan (NAP) required by §290.46(z) of this title (relating to Minimum Acceptable Operating Practices for Public Drinking Water Systems). Sample results determined by monitoring required under this paragraph will not be used to determine compliance with the maximum contaminant levels, MRDLs, action levels, or treatment techniques of this subchapter.

§290.110(c)(5)(A) Source water. Public water systems must monitor source water (including raw and treated purchased water) to establish baseline ammonia, nitrite, and nitrate levels (all as nitrogen) at least once to determine the availability of ammonia for chloramine formation and to provide a reference for downstream nitrite and nitrate levels that may indicate nitrification. If any source has more than 0.5 mg/L free ammonia (as nitrogen) in the initial sample, then raw water ammonia (as nitrogen) shall be monitored monthly for six months to determine the baseline free ammonia level.

§290.110(c)(5)(B) Water entering distribution system. All public water systems that have chloramines present shall perform sampling to represent the water entering the distribution system.

§290.110(c)(5)(B)(i) Total chlorine, free ammonia (as nitrogen) and monochloramine shall be monitored weekly at all entry points to the distribution system or at a location before the first customer.

§290.110(c)(5)(B)(ii) Nitrite and nitrate (as nitrogen) levels at the first customer shall be monitored monthly for at least six months to determine baseline nitrite and nitrate levels in the water prior to consumption. Nitrite and nitrate samples collected at the first customer will not be used for compliance with §290.106 of this title (relating to Inorganic Contaminants).

§290.110(c)(5)(B)(iii) Nitrite and nitrate (as nitrogen) shall be monitored quarterly at the first customer after establishing the baseline. Nitrite and nitrate samples collected at entry points for compliance with §290.106 of this title may be used for these quarterly samples.

§290.110(c)(5)(C) Treatment sampling. Public water systems that inject chlorine at any location to form chloramines or to convert from chloramines to free chlorine must monitor to ensure that chemical addition is effective and the proper chlorine to ammonia (as nitrogen) ratio is achieved. Samples must be collected and analyzed weekly and whenever the chemical dosage is changed.

§290.110(c)(5)(C)(i) Sampling must be performed upstream of the chlorine or ammonia chemical injection point, whichever is furthest upstream.

§290.110(c)(5)(C)(ii) Sampling must be performed downstream of all the chlorine and ammonia chemical injection points.

§290.110(c)(5)(C)(iii) The residual of the chemical injected upstream must be determined to properly dose the downstream chemical where sample taps are present or required under §290.42(e)(7)(C)(ii) of this title (relating to Water Treatment).

§290.110(c)(5)(C)(iv) The total chlorine, ammonia (as nitrogen), and monochloramine residuals must all be monitored if the treatment occurs before the entry point.

§290.110(c)(5)(C)(v) The ammonia (as nitrogen) and monochloramine residuals must all be monitored if the treatment occurs in the distribution system. The monitoring must occur at the same time as a compliance sampling required under paragraph (4)(E) of this subsection.

§290.110(c)(5)(D) Distribution system. Public water systems that distribute water and have a chloramine residual must ensure the efficacy of disinfection within the distribution system.

§290.110(c)(5)(D)(i) Monochloramine and free ammonia (as nitrogen) must be monitored weekly at the same time as a compliance sample required under paragraph (4) of this subsection.

§290.110(c)(5)(D)(ii) Nitrite and nitrate (as nitrogen) must be monitored quarterly.

§290.110(d) Analytical requirements. All monitoring required by paragraphs (1) and (2) of this subsection must be conducted at a facility approved by the executive director and using methods that conform to the requirements of §290.119 of this title (relating to Analytical Procedures). All monitoring for chloramine effectiveness required by paragraphs (3) - (6) of this subsection must be analyzed to the accuracy provided therein.

§290.110(d)(1) The free chlorine or chloramine residual (measured as total chlorine) must be measured to a minimum accuracy of plus or minus 0.1 mg/L. Color comparators may be used for distribution system samples only. When used, a color comparator must have current reagents, an unfaded and clear color comparator, a sample cell that is not discolored or stained, and must be properly stored in a cool, dark location where it is not subjected to conditions that would result in staining. The color comparator must be used in the correct range. If a sample reads at the top of the range, the sample must be diluted with chlorine-free water, then a reading taken and the resulting residual calculated.

§290.110(d)(2) The chlorine dioxide residual must be measured to a minimum accuracy of plus or minus 0.05 mg/L using a method that conforms to the requirements of §290.119 of this title. The DPD-glycine method using a colorimeter or spectrophotometer may be utilized only with the written permission of the executive director.

§290.110(d)(3) The free ammonia level must be measured to a minimum accuracy of plus or minus 0.1 mg/L.

§290.110(d)(4) The monochloramine level must be measured to a minimum accuracy of plus or minus 0.15 mg/L using a procedure that has the ability to distinguish between monochloramine and other forms of chloramine.

§290.110(d)(5) The nitrate (as nitrogen) level must be measured to a minimum accuracy of plus or minus 0.1 mg/L.

§290.110(d)(6) The nitrite (as nitrogen) level must be measured to a minimum accuracy of plus or minus 0.01 mg/L.

§290.110(e) Reporting requirements. Any owner or operator of a public water system subject to the provisions of this section is required to report to the executive director the results of any test, measurement, or analysis required by this section.

§290.110(e)(1) Public water systems exceeding the MRDL for chlorine dioxide in subsection (b)(3) of this section must report the exceedance to the executive director within 24 hours of the event.

§290.110(e)(2) Public water systems that use surface water sources or groundwater sources under the direct influence of surface water must submit a Surface Water Monthly Operating Report (commission Form 0102C), a Surface Water Monthly Operating Report (commission Form 0102D) for alternative technologies, or a Surface Water Monthly Operational Report for Plants That Do Not Have a Turbidimeter on Each Filter (commission Form 0103) each month.

§290.110(e)(3) Public water systems that use chlorine dioxide must submit a Chlorine Dioxide Monthly Operating Report (commission Form 0690) each month.

§290.110(e)(4) Public water systems that use purchased water or groundwater sources only must complete a Disinfection Level Quarterly Operating Report (commission Form 20067) each quarter.

§290.110(e)(4)(A) Community and nontransient, noncommunity public water systems must submit the Disinfection Level Quarterly Operating Report each quarter, by the tenth day of the month following the end of the quarter.

§290.110(e)(4)(B) Transient, noncommunity public water systems must retain the Disinfection Level Quarterly Operating Reports and must provide a copy if requested by the executive director.

§290.110(e)(5) Systems that use chloramines must retain their NAP required under §290.46(z) of this title and must provide a copy upon request by the executive director.

§290.110(e)(6) Monthly and quarterly reports required by this section must be submitted to the Water Supply Division, MC 155, Texas Commission on Environmental Quality, P.O. Box 13087, Austin, Texas 78711-3087 by the tenth day of the month following the end of the reporting period.

§290.110(f) Compliance determinations. Compliance with the requirements of this section shall be determined using the following criteria.

§290.110(f)(1) All samples used for compliance must be obtained at sampling sites designated in the monitoring plan.

§290.110(f)(1)(A) All samples collected at sites designated in the monitoring plan as microbiological and disinfectant residual monitoring sites shall be included in the compliance determination calculations.

§290.110(f)(1)(B) Samples collected at sites in the distribution system not designated in the monitoring plan shall not be included in the compliance determination calculations.

§290.110(f)(2) A public water system that fails to conduct the monitoring tests required by this section commits a monitoring violation.

§290.110(f)(3) A public water system that fails to report the results of the monitoring tests required by this section commits a reporting violation.

§290.110(f)(4) A public water system that uses surface water sources or groundwater sources under the direct influence of surface water and fails to meet the requirements of subsection (b)(2) of this section for a period longer than four consecutive hours commits a nonacute treatment technique violation. A public water system that fails to conduct the additional testing required by subsection (c)(1)(B)(iii) of this section also commits a nonacute treatment technique violation.

§290.110(f)(5) A public water system that uses chlorine dioxide and exceeds the level specified in subsection (b)(3) of this section violates the MRDL for chlorine dioxide.

§290.110(f)(5)(A) If a public water system violates the MRDL for chlorine dioxide and any of the three additional distribution samples exceeds the MRDL, the system commits an acute MRDL violation for chlorine dioxide.

§290.110(f)(5)(B) If a public water system violates the MRDL for chlorine dioxide and fails to collect each of the three additional distribution samples required by subsection (c)(3) of this section, the system commits an acute MRDL violation for chlorine dioxide.

§290.110(f)(5)(C) If a public water system violates the MRDL for chlorine dioxide but none of the three additional distribution samples violates the MRDL, the system commits a nonacute MRDL violation for chlorine dioxide.

§290.110(f)(6) A public water system that fails to meet the requirements of subsection (b)(4) of this section, in more than 5.0% of the samples collected each month, for any two consecutive months, commits a nonacute treatment technique violation. Specifically, the system commits a nonacute violation if the value “V” in the following formula exceeds 5.0% per month for any two consecutive months:

Figure 1. 30 TAC §290.110(f)(6)

Where:

a = number of instances where the residual disinfectant concentration is measured during the month; and

b = number of instances during the month where the residual disinfectant concentration is measured but is detected at less than 0.2 milligrams per liter (mg/L) free chlorine or less than 0.5 mg/L chloramine (measured as total chlorine).

§290.110(f)(7) A public water system violates the MRDL for chlorine or chloramine (measured as total chlorine) if, at the end of any quarter, the running annual average of monthly averages exceeds the level specified in subsection (b)(5) of this section.

§290.110(f)(8) Public water systems shall increase residual disinfectant levels of free chlorine, or chloramines measured as total chlorine, (but not chlorine dioxide) in the distribution system to a level and for a time necessary to protect public health to address specific microbiological contamination problems caused by circumstances such as distribution line breaks, storm runoff events, source water contamination, or cross- connections. Public water systems shall consult with the executive director upon increasing residual disinfectant levels in the distribution system in order to maintain compliance with the MRDLs listed in subsection (b) of this section.

§290.110(f)(9) If a public water system’s failure to monitor makes it impossible to determine compliance with the MRDL for chlorine or chloramines (measured as total chlorine), the system commits an MRDL violation for the entire period covered by the annual average.

§290.110(f)(10) A public water system that fails to issue a required public notice or certify that it has issued that notice commits a violation.

§290.110(g) Public notification requirements. The owner or operator of a public water system that violates the requirements of this section must notify the executive director and the people served by the system.

§290.110(g)(1) A public water system that fails to meet the requirements of subsection (b)(3) of this section, shall notify the executive director within 24 hours of the event and the customers in accordance with the requirements of §290.122 of this title (relating to Public Notification).

§290.110(g)(1)(A) A public water system that has an acute violation of the MRDL for chlorine dioxide must notify the customers in accordance with the requirements of §290.122(a) of this title.

§290.110(g)(1)(B) A public water system that has a non-acute violation of the MRDL for chlorine dioxide must notify the customers in accordance with the requirements of §290.122(b) of this title.

§290.110(g)(2) A public water system that uses surface water sources or groundwater sources under the direct influence of surface water and fails to meet the minimum disinfection requirements of subsection (b)(2) of this section shall notify the executive director by the end of the next business day and the customers in accordance with the requirements of §290.122(b) of this title.

§290.110(g)(3) A public water system that fails to meet the requirements of subsection (b)(4) of this section in more than 5.0% of the samples collected each month for two consecutive months must notify its customers in accordance with the requirements of §290.122(b) of this title.

§290.110(g)(4) A public water system that fails to meet the requirements of subsection (b)(5) of this section shall notify the executive director by the end of the next business day and the customers in accordance with the requirements of §290.122(b) of this title.

§290.110(g)(5) A public water system which fails to conduct the monitoring required by subsection (c)(1) - (4) of this section must notify its customers of the violation in accordance with the requirements of §290.122(c) of this title.

§290.110(g)(6) A public water system that uses chloramines shall notify their retail and wholesale customers of the use of chloramines.

§290.110(g)(6)(A) This notification must contain the exact wording included in Appendix H of §290.47 of this title (relating to Appendices).

§290.110(g)(6)(B) Prior to initially providing the chloraminated water to its existing customers, the water system must provide notification by mail or direct delivery at least 14 days before the change.

§290.110(g)(6)(C) Additionally, the notification must be provided to the news media, hospitals, renal disease facilities, dialysis clinics, physicians, local health departments, and entities which maintain live fish directly by letter, e-mail, or hand delivery.

§290.110(g)(6)(D) New customers must also be notified before they begin receiving water from the water system.

§290.110(g)(6)(E) Where appropriate, the notice must be multilingual.

Source Note: The provisions of this §290.110 adopted to be effective September 13, 2000, 25 TexReg 8880; amended to be effective May 16, 2002, 27 TexReg 4127; amended to be effective January 9, 2008, 33 TexReg 198; amended to be effective November 8, 2012, 37 TexReg 8849; amended to be effective July 30, 2015, 40 TexReg 4769; amended to be effective March 30, 2017, 42 TexReg 1466

§290.111. Surface Water Treatment

§290.111(a) Applicability. A public water system that treats surface water or groundwater under the direct influence of surface water must comply with the requirements of this section.

§290.111(a)(1) A public water system that treats surface water must comply with the requirements of this section beginning on the effective date of the rule.

§290.111(a)(2) A public water system that treats groundwater under the direct influence of surface water must comply with the requirements of this section beginning on a date specified by the executive director. This compliance date shall not exceed 18 months from the date that the executive director first notifies the system that the groundwater source is under the direct influence of surface water.

§290.111(a)(3) A public water system that treats both surface water and groundwater under the direct influence of surface water must meet the compliance date in paragraph

1. of this subsection at plants that treat any surface water and must meet the compliance date in paragraph (2) of this subsection at plants that treat only groundwater under the direct influence of surface water.

§290.111(b) Raw surface water monitoring. A public water system that treats surface water or groundwater under the direct influence of surface water must conduct at least two rounds of special raw surface water monitoring at each surface water intake and at each well producing groundwater under the direct influence of surface water for the purpose of establishing minimum treatment technique requirements for Cryptosporidium and other pathogens. The executive director may waive the raw surface water monitoring requirements for an intake or a well if the combination of pathogen removal and disinfection processes used to treat the raw water achieves at least a 5.5-log total removal and inactivation of Cryptosporidium parvum.

§290.111(b)(1) Raw water monitoring plans. A system must submit a proposed raw surface water monitoring plan when requested by the executive director. The proposed plan must identify all of the system’s intakes and wells; provide the location of each raw water sampling point; include the parameters that will be monitored and the frequency and dates that samples will be collected; and specify the laboratories that will perform the analyses. Raw surface water monitoring must be conducted in accordance with a monitoring plan that has been approved by the executive director. The executive director shall not approve a raw surface water monitoring plan unless it indicates that the system will meet the requirements of 40 Code of Federal Regulations (CFR) §§141.701 - 141.707.

§290.111(b)(2) Sampling location. A system must collect each raw water sample at a location approved by the executive director. Samples must be collected from the raw water line prior to any treatment and before the first point where a recycled stream is returned to the treatment process.

§290.111(b)(3) Sampling parameters and frequency. A system must collect raw water samples at a frequency approved by the executive director.

§290.111(b)(3)(A) Unless the executive director approves an alternate sampling regimen, a system must monitor turbidity, Escherichia coli (E. coli), and Cryptosporidium levels in the raw water at least once each month for a period of not less than 24 consecutive months if the system:

§290.111(b)(3)(A)(i) serves at least 10,000 people; or

§290.111(b)(3)(A)(ii) is part of combined distribution system in which one or more systems serve at least 10,000 people and the system with the well or intake regularly provides water to another public water supply.

§290.111(b)(3)(B) A system that is not required to monitor under subparagraph (A) of this paragraph must either monitor in accordance with the requirements of subparagraph (A) of this paragraph or monitor E. coli levels in their raw water at least once every two weeks for a period of not less than 12 consecutive months. A system that does not initially monitor for Cryptosporidium and has elevated E. coli levels must conduct additional raw water monitoring.

§290.111(b)(3)(B)(i) A system must conduct additional monitoring if the average E. coli level exceeds 100 colony-forming units per 100 milliliters in the raw water produced by a surface water intake located on a river or flowing stream or the raw water from a well producing groundwater under the direct influence of surface water located closest to a river or flowing stream.

§290.111(b)(3)(B)(ii) A system must conduct additional monitoring if the average E. coli level exceeds 100 colony-forming units per 100 milliliters in the raw water from a surface water intake not located on a river or flowing stream or the raw water produced by a well producing groundwater under the direct influence of surface water not located on a river or flowing stream.

§290.111(b)(3)(B)(iii) A system that must conduct additional monitoring must monitor Cryptosporidium levels in the raw water at least twice each month for a period of not less than 12 consecutive months, or at least once each month for a period of not less than 24 consecutive months.

§290.111(b)(3)(C) The executive director may approve an alternate sampling frequency for intakes and wells that operate only part of the year.

§290.111(b)(4) Sampling schedule and dates. A system must collect raw water samples in accordance with a schedule approved by the executive director.

§290.111(b)(4)(A) Except as provided in subparagraph (B) of this paragraph, a system must begin each round of raw source water monitoring no later than the date shown in the following table titled “Raw Source Water Monitoring Schedule.”

TCEQ Publication RG-346§290.111. Surface Water Treatment

Table 11: §290.111(b)(4)(A) Raw Source Water Monitoring Schedule

1 Systems that provide treated surface water to another system and are part of a combined distribution system must begin monitoring at the same time as the system in the combined distribution system that has the earliest compliance date.

§290.111(b)(4)(B) If a system installs a new well or intake after the date the first round of raw source water monitoring must begin, the system must:

§290.111(b)(4)(B)(i) submit a proposed monitoring schedule for the first round of special raw surface water monitoring no later than three months after first placing the new source in operation; and

§290.111(b)(4)(B)(ii) begin the second round of special raw surface water monitoring no later than six years after initial bin classification.

§290.111(b)(4)(C) A system must collect a raw water sample no sooner than two days before the date approved by the executive director and no later than two days after the approved date, unless an extreme condition or situation exists that poses a danger to the sample collector.

§290.111(b)(4)(D) A system which is unable to collect a sample within this five-day period must collect the sample as close as possible to the approved date and must notify the executive director in writing why the sample was not collected on the approved date.

§290.111(b)(5) Replacement samples. If, for any reason, the laboratory is unable to report a valid analytical result for a scheduled sample, the system must submit a replacement sample on a date approved by the executive director.

§290.111(b)(6) Analytical requirements. Raw water samples collected pursuant to this subsection must be analyzed at an United States Environmental Protection Agency (EPA) approved or a Texas Commission on Environmental Quality accredited laboratory.

§290.111(b)(6)(A) Cryptosporidium samples must be analyzed using one of the methods approved in 40 CFR §141.704(a) and by a laboratory that is approved under EPA’s Laboratory Quality Assurance Evaluation Program for Analysis of Cryptosporidium in Water.

§290.111(b)(6)(B) E. coli samples must be analyzed using one of the methods approved in 40 CFR §136.3(a) for the enumeration of E. coli in source water and by a laboratory that is accredited by the executive director.

§290.111(b)(6)(B)(i) Systems must ensure that samples are maintained between 0 degrees Celsius and 10 degrees Celsius during storage and transportation to the laboratory.

§290.111(b)(6)(B)(ii) The time between sample collection and the initiation of the analysis may not exceed 30 hours without the prior approval of the executive director.

§290.111(b)(6)(B)(iii) The executive director may allow up to 48 hours between sample collection and the initiation of the analysis if the analysis is conducted by the Colilert reagent version of Standard Method 9223B.

§290.111(b)(6)(C) Turbidity samples must be analyzed using a method and at a laboratory approved by the executive director.

§290.111(b)(7) Reporting requirements for raw surface water sample results. The owner or operator of a public water system must provide to the executive director with a copy of the results of any test, measurement, or analysis required by this subsection.

§290.111(b)(7)(A) Results must be submitted using the Raw Surface Water Sampling Report (commission Form 20358) or in another format that is approved by the executive director and contains the information required by 40 CFR §141.706(e).

§290.111(b)(7)(A)(i) If the sample was not collected within the five-day window described in paragraph (4)(C) of this subsection, the result must be accompanied by the information required in paragraph (4)(D) of this subsection.

§290.111(b)(7)(A)(ii) If the laboratory report indicates that a valid analytical result could not be reported, the laboratory report must be accompanied by a request to collect a replacement sample.

§290.111(b)(7)(B) The results must be submitted within ten days of their receipt by the public water system and no later than ten days after the end of the first month following the month that the sample was collected.

§290.111(b)(7)(C) The results and any additional information must be mailed to the Water Supply Division, MC 155, Texas Commission on Environmental Quality, P.O. Box 13087, Austin, Texas 78711-3087.

§290.111(c) Treatment technique requirements. A system that treats surface water or groundwater under the direct influence of surface water must meet minimum treatment technique requirements before the water reaches the entry point to the distribution system.

§290.111(c)(1) The combination of pathogen removal and disinfection processes used by a public water system must achieve at least a 4.0-log removal/inactivation of viruses.

§290.111(c)(2) The combination of pathogen removal and disinfection processes used by a public water system must achieve at least a 3.0-log removal/inactivation of Giardia lamblia.

§290.111(c)(3) A public water system that is required by subsection (b) of this section to conduct raw surface water monitoring must comply with the requirements of this paragraph.

§290.111(c)(3)(A) The average Cryptosporidium level and bin classification shall be determined in accordance with the requirements established by 40 CFR §141.710.

§290.111(c)(3)(A)(i) For systems that collect a total of at least 48 Cryptosporidium samples, the average concentration is equal to the arithmetic mean of all sample concentrations.

§290.111(c)(3)(A)(ii) For systems that collect a total of at least 24 samples, but not more than 47 Cryptosporidium samples, the average concentration is equal to the highest arithmetic mean of all sample concentrations in any 12 consecutive months during which Cryptosporidium samples were collected.

§290.111(c)(3)(A)(iii) For systems that serve fewer than 10,000 people and monitor for Cryptosporidium for only one year (i.e., collect 24 samples in 12 months), the average concentration is equal to the arithmetic mean of all sample concentrations.

§290.111(c)(3)(A)(iv) For systems with plants operating only part of the year that monitor fewer than 12 months per year under 40 CFR §141.701(e), the bin concentration is equal to the highest arithmetic mean of all sample concentrations during any year of Cryptosporidium monitoring.

§290.111(c)(3)(A)(v) If the monthly Cryptosporidium sampling frequency varies, systems must first calculate a monthly average for each month of monitoring. Systems must then use these monthly average concentrations, rather than individual sample concentrations, in the applicable calculation for bin classification in paragraphs.

§290.111(c)(3)(B) Unless otherwise specified in this paragraph, the combination of pathogen removal and disinfection processes must achieve the removal/inactivation of Cryptosporidium parvum specified in the following table titled “Treatment

Technique Requirements for Cryptosporidium,” beginning 36 months after being assigned a bin classification by the executive director.

Table 12: §290.111(c)(3)(B) Treatment Technique Requirements for Cryptosporidium1

1 The executive director will assign Cryptosporidium removal credit based on the treatment processes used at the plant:

1. Treatment plants utilizing coagulation, flocculation, and granular media filtration will receive a
   2.5-log Cryptosporidium removal credit.
2. Treatment plants utilizing coagulation, flocculation, clarification, and granular media filtration will receive a 3.0-log Cryptosporidium removal credit.
3. The executive director will assign Cryptosporidium removal credit to treatment plants utilizing bag, cartridge, or membrane filters on an individual basis.

§290.111(c)(3)(B)(i) A system that conducts the first round of special raw surface water monitoring according to the schedule contained in subsection (b)(4)(A) of this section must comply with the requirements of this paragraph no later than the date shown in the following table, titled “Compliance Date for Existing Sources.”

Table 13: §290.111(c)(3)(B)(i) Compliance Date for Existing Sources

§290.111(c)(3)(B)(ii) A system that conducts the first round of special raw surface water monitoring according to the schedule contained in subsection

(b)(4)(B)(i) of this section must comply with the requirements of this paragraph no later than six years after beginning the first round of monitoring on the new source.

§290.111(c)(3)(B)(iii) The executive director may allow a system making capital improvements an additional two years to comply with the treatment requirement of this paragraph.

§290.111(c)(3)(C) A system that has been assigned to Bin 3 or Bin 4 must achieve at least 1.0-log removal/inactivation of Cryptosporidium using one or a combination of the following: bag filters, cartridge filters, chlorine dioxide, membranes, ozone, or ultraviolet light (UV).

§290.111(c)(3)(D) Prior to the effective date of subparagraph (B) of this paragraph, the combination of disinfection and filtration processes used by a public water system to treat for Cryptosporidium must achieve at least a 2.0-log removal/inactivation of Cryptosporidium parvum.

§290.111(c)(4) The combination of disinfection and filtration processes at plants that do not monitor each source in accordance with the requirements of subsection (b) of this section must achieve at least a 5.5-log removal/inactivation of Cryptosporidium parvum.

§290.111(c)(5) The executive director may require additional levels of treatment in cases of poor source water quality.

§290.111(c)(6) The executive director may establish minimum design, operational, and reporting requirements for watershed control programs and treatment processes used to meet the treatment technique requirements of this subsection.

§290.111(d) Microbial inactivation requirements. A system that treats surface water or groundwater under the direct influence of surface water must meet minimum disinfection requirements before the water is supplied to any consumer.

§290.111(d)(1) Inactivation table. The disinfection process must achieve the minimum microbial inactivation levels shown in the following table.

1. Filters in which water passes through a porous granular media and which utilize depth filtration processes.
2. Filters in which particulate matter larger than 1 micrometer is rejected by an engineered barrier, primarily through a size-exclusion mechanism.
3. The executive director will determine the required Giardia inactivation on a case-by-case basis.
4. NA = Not Allowed. Conventional filtration with no coagulation is not allowed to receive Giardia or viral treatment credit.
5. NA = Not Allowed. Conventional filtration with no coagulation is not allowed to receive Giardia or viral treatment credit.