Original Notice.

     Preproposal statement of inquiry was filed as WSR 03-07-103.

     Title of Rule: Group A public drinking water system regulation, chapter 246-290 WAC.

     Purpose: The purpose is to adopt revisions necessary to be consistent with federally promulgated Environmental Protection Agency (EPA) rules and regulations. The proposed revisions amend WAC 246-290-010, 246-290-025, 246-290-130, 246-290-300, 246-290-310, 246-290-320, 246-290-480, 246-290-601, 246-290-630, 246-290-660, 246-290-664, 246-290-666, 246-290-72010, and 246-290-72012.

     Statutory Authority for Adoption: RCW 43.20.050.

     Statute Being Implemented: RCW 70.119A.080.

     Summary: The proposed revisions: (1) Add requirements to improve microbial control in water systems using surface water sources that serve fewer than 10,000 people; (2) revises the maximum contaminant level (MCL) for arsenic from 0.05 mg/L to 0.010 mg/L for community and nontransient noncommunity systems; and (3) removes the arsenic MCL for transient noncommunity (TNC) water systems.

     Reasons Supporting Proposal: As the primacy agency, the Department of Health is responsible for implementing rules no less stringent than EPA rules and regulations. These rule revisions are required to maintain our primacy agreement with EPA and sustain federal funding.

     Name of Agency Personnel Responsible for Drafting: Theresa Phillips, Tumwater, (360) 236-3147; Implementation and Enforcement: Richard Siffert, Tumwater, (360) 236-3146.

     Name of Proponent: Department of Health, Division of Environmental Health, governmental.

     Rule is necessary because of federal law, 40 C.F.R., Parts 9, 141, 142.

     Explanation of Rule, its Purpose, and Anticipated Effects: The proposed rule revisions will achieve compliance with the new federal requirements to maintain state primacy. The revisions are necessary to: (1) Strengthen protection against microbial contamination for public water systems using surface water sources, serving fewer than 10,000 people; (2) strengthen protection from long-term exposure to arsenic for community and nontransient noncommunity water systems; and (3) clarify current rule language.

     Proposal Changes the Following Existing Rules: The proposed rule revisions change existing rules by adding requirements to improve control of microbial pathogens, specifically Cryptosporidium for public water systems using surface water sources that serve fewer than 10,000 people. The proposed revisions amend WAC 246-290-010 Definitions, 246-290-025 Adoption by reference, 246-290-480 Recordkeeping and reporting, 246-290-601 purpose of surface water treatment, 246-290-630 General requirements, 246-290-660 Filtration, 246-290-664 Monitoring for filtered systems, and 246-290-666 Reporting for filtered systems. The proposed revisions also amend the MCL for arsenic from 0.05 mg/L (50 ppb) to 0.010 mg/L (10 ppb) for community and nontransient noncommunity water systems; revises the timeframe for when the new MCL applies to new systems and existing systems with new sources; modifies the calculation for determining when a system violates the MCL from a single sample with a confirmation sample to a running annual average; removes the arsenic MCL for transient noncommunity water systems; and clarifies current rule language. The proposed revisions amend WAC 246-290-025 Adoption by reference, 246-290-130 Source approval, 246-290-300 Monitoring requirements, 246-290-310 Maximum contaminant levels and maximum residual disinfectant levels, 246-290-320 Follow-up action, 246-290-72010 Report contents -- Required additional health information, and 246-290-72012 Regulated contaminants.

     No small business economic impact statement has been prepared under chapter 19.85 RCW. Parts of this rule revision are exempt from the small business economic impact statement requirement under RCW 19.85.025(3) because it adopts federal regulations without material change. The only part of the rule revision that is not exempt for this reason concerns the removal of the current arsenic MCL for TNC water systems. This revision does not impose any additional costs on the regulated community, therefore falls under the minor impact threshold.

     RCW 34.05.328 applies to this rule adoption. Parts of the rule are exempt from the statute because they "adopt federal regulations without material change." The part of the rule revision that is not exempt concerns the removal of the existing arsenic MCL for TNC water systems. This part of the rule qualifies as legislatively significant under RCW 34.05.328 (5)(c)(iii) because it significantly amends a regulatory program.

     Hearing Location: Department of Health, Point Plaza East, 310 Israel Road S.E., Tumwater, WA 98504, on January 14, 2004, at 1:30 p.m.

     Assistance for Persons with Disabilities: Contact Theresa Phillips by January 2, 2004, TDD (800) 833-6388 or (360) 236-3147.

     Submit Written Comments to: Department of Health, Theresa Phillips, P.O. Box 47822, Olympia, WA 98504-7822, fax (360) 236-2253, by January 7, 2004.

     Date of Intended Adoption: January 14, 2004.

December 2, 2003

Don Sloma

Executive Director

OTS-6565.3

AMENDATORY SECTION(Amending WSR 99-07-021, filed 3/9/99, effective 4/9/99)

WAC 246-290-130   Source approval.   (1) Every purveyor shall obtain drinking water from the highest quality source feasible. No new source, previously unapproved source, or modification of an existing source shall be used as a public water supply without department approval. No intake or other connection shall be maintained between a public water system and a source of water not approved by the department.

     (2) Before initiating source development or modification, the purveyor shall contact the department to identify submittal requirements.

     (3) Any party seeking source approval shall provide the department sufficient documentation, in a project report, construction documents, or in supplemental documents, that the source:

     (a) Is reasonable and feasible for the type and size of the system;

     (b) May legally be used in conformance with state water rights laws;

     (c) Supplies water that is physically and reliably available in the necessary quantities, as shown in:

     (i) A hydrogeologic assessment of the proposed source;

     (ii) A general description of the watershed, spring, and/or aquifer recharge area affecting the quantity or quality of flow, which includes seasonal variation and upstream water uses that may significantly affect the proposed source;

     (iii) For ground water and spring sources, well source development data that are available from a pump test at the maximum design rate and duration, or are available from other sources of information, that establish pump settings (depth) in the well and demonstrate adequacy of water quantity to meet design criteria while not leading to water quality problems;

     (iv) For ground water and spring sources, installation of a source meter or other equivalent device that reliably measures volume of flow into the system;

     (d) Is, or is not, a GWI under WAC 246-290-640, and meets or can meet the applicable requirements for GWI sources as described in that section including treatment;

     (e) Adequately provides for source protection, as shown in:

     (i) For surface water and GWI sources, the watershed control program identified under WAC 246-290-135 and Part 6 of this chapter;

     (ii) For wells, a preliminary department susceptibility assessment or equivalent information, and preliminary WHPA delineation and contaminant inventory, under the requirements for sanitary control and wellhead protection under WAC 246-290-135;

     (f) Is designed and constructed in conformance with this chapter, and relevant requirements of chapter 173-160 WAC (department of ecology well construction standards);

     (g) Meets water quality standards under WAC 246-290-310, as shown in an initial water quality analysis that includes, at a minimum, the following:

     (i) Bacteriological;

     (ii) Complete inorganic chemical and physical except that the MCL for arsenic under WAC 246-290-310 does not apply to TNC systems;

     (iii) Complete VOC;

     (iv) Radionuclides, if source approval is requested for a community system;

     (v) SOC, except where waived or not required under WAC 246-290-310; and

     (vi) Any other information required by the department relevant to the circumstances of the particular source.

     Sources that otherwise would not meet water quality standards may be approved if treatment is provided.

     (4) The required documentation under subsection (3) of this section shall include, at a minimum:

     (a) A copy of the water right, or other written evidence of the existence of the right;

     (b) A map showing the project location and vicinity;

     (c) A map depicting topography, distances to the surface water intake, well or spring from existing property lines, buildings, potential sources of contamination, ditches, drainage patterns, and any other natural or man-made features affecting the quality or quantity of water;

     (d) The dimensions, location, and legal documentation of the sanitary control area (SCA) under WAC 246-290-135;

     (e) A copy of the on-site inspection form completed by the department or local health department representative;

     (f) A copy of the water well report including the unique well identification tag number, depth to open interval or top of screened interval, overall depth of well from the top of the casing, vertical elevation, and location (both plat location and latitude/longitude); and

     (g) Documentation of source meter installation. The purveyor may utilize other documents, such as a water system plan, susceptibility assessment, wellhead protection program, project report, or construction documents, to provide such documentation and information to the department, provided that such documents are current, and the purveyor indicates the location in the document of the relevant information.

     (5) If treatment of a source is necessary to meet water quality standards, the purveyor may be required to meet the provisions of WAC 246-290-250 and Part 6 of this chapter, if applicable, prior to or as a condition of approval.

     (6) An intertie must be adequately described in a written agreement between the purveyor and the supplier of the water, and otherwise meet the requirements of WAC 246-290-132.

     (7) The purveyor shall not construct facilities for source development and use without prior approval of the department pursuant to the provisions of WAC 246-290-120.

     (8) The purveyor shall receive a written source approval when:

     (a) The purveyor has complied with the relevant provisions of subsections (1) through (7) of this section; and

     (b) The developed source provides water complying with this chapter.

     (9) The purveyor may receive a conditional source approval, such as one that sets limits on use or requires interim treatment, if further analysis of the quality of the source is required before final approval.

     (10) For sources or supplies of water used by bottled water or ice plants to produce bottled water or ice:

     (a) If the bottled water or ice plant is a Group A community water system and the plant uses the system's source for the water that is bottled or made into ice, the source and supply used for the bottled water and ice shall meet the applicable Group A requirements;

     (b) If the bottled water or ice plant uses its own source for the water that is bottled or made into ice, and the plant is not a Group A community water system, the owner or operator shall obtain source approval from the department, and the source water shall meet the ongoing source water quality monitoring requirements for a Group A community system;

     (c) If the bottled water or ice plant purchases the water for bottling or making ice from another source or supply, the water shall meet the minimum requirements for a Group A community water system, and the owner or operator of the plant shall ensure that the water meets such requirements;

     (d) The source or supply for the water that is bottled or made into ice shall be protected from contamination prior to the bottling or ice making process; and

     (e) In addition to the requirements imposed under this subsection, the processing of bottled water shall be subject to regulation by the state department of agriculture and the United States Food and Drug Administration.

[Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-130, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-130, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-130, filed 3/25/93, effective 4/25/93. Statutory Authority: Chapter 43.20 RCW. 91-07-031 (Order 150B), § 246-290-130, filed 3/15/91, effective 4/15/91. Statutory Authority: RCW 43.20.050. 91-02-051 (Order 124B), recodified as § 246-290-130, filed 12/27/90, effective 1/31/91. Statutory Authority: P.L. 99-339. 89-21-020 (Order 336), § 248-54-097, filed 10/10/89, effective 11/10/89. Statutory Authority: RCW 34.04.045. 88-05-057 (Order 307), § 248-54-097, filed 2/17/88.]

     (a) The monitoring requirements specified in this section are minimums. The department may require additional monitoring when:

     (i) Contamination is present or suspected in the water system;

     (ii) A ground water source is determined to be a potential GWI;

     (iii) The degree of source protection is not satisfactory;

     (iv) Additional monitoring is needed to verify source vulnerability for a requested monitoring waiver;

     (v) Under other circumstances as identified in a departmental order; or

     (vi) Additional monitoring is needed to evaluate continuing effectiveness of a treatment process where problems with the treatment process may exist.

     (b) Special purpose samples collected by the purveyor shall not count toward fulfillment of the monitoring requirements of this chapter unless the quality of data and method of sampling and analysis are acceptable to the department.

     (c) The purveyor shall ensure samples required by this chapter are collected, transported, and submitted for analysis according to EPA-approved methods. The analyses shall be performed by a laboratory accredited by the state. Qualified water utility, accredited laboratory, health department personnel, and other parties approved by the department may conduct measurements for pH, temperature, residual disinfectant concentration, alkalinity, bromide, chlorite, TOC, SUVA, and turbidity as required by this chapter, provided, these measurements are made in accordance with EPA approved methods.

     (d) Compliance samples required by this chapter shall be taken at locations listed in Table 3 of this section.

     (e) Purveyors failing to comply with a monitoring requirement shall notify:

     (i) The department in accordance with WAC 246-290-480; and

     (ii) The owner or operator of any consecutive system served and the appropriate water system users in accordance with 40 CFR 141.201 and Part 7, Subpart A of this chapter.

     (2) Selling and receiving water.

     (a) Source monitoring. Purveyors, with the exception of those that "wheel" water to their consumers (i.e., sell water that has passed through another purchasing purveyor's distribution system), shall conduct source monitoring in accordance with this chapter for the sources under their control. The level of monitoring shall satisfy the monitoring requirements associated with the total population served by the source.

     (b) Distribution system monitoring. The purveyor of a system that receives and distributes water shall perform distribution-related monitoring requirements. Monitoring shall include, but not be limited to, the following:

     (i) Collect coliform samples in accordance with subsection (3) of this section;

     (ii) Collect trihalomethane samples if required by subsection (6) of this section or disinfection by-product samples if required by subsection (7) of this section;

     (iii) Perform the distribution system residual disinfectant concentration monitoring in accordance with subsection (7) of this section, and as required under WAC 246-290-451 or 246-290-694;

     (iv) Perform lead and copper monitoring required under 40 CFR 141.86, 141.87, and 141.88;

     (v) Perform the distribution system monitoring in accordance with 40 CFR 141.23(b) for asbestos if applicable;

     (vi) Other monitoring as required by the department.

     (c) Reduced monitoring for regional programs. The receiving purveyor may receive reductions in the coliform, lead and copper, disinfection by-product (including THMs) and distribution system disinfectant residual concentration monitoring requirements, provided the receiving system:

     (i) Purchases water from a purveyor that has a department-approved regional monitoring program; and

     (ii) Has a written agreement with the supplying system or regional water supplier that is acceptable to the department, and which identifies the responsibilities of both the supplying and receiving system(s) with regards to monitoring, reporting and maintenance of the distribution system.

     (d) Periodic review of regional programs. The department may periodically review the sampling records of public water systems participating in a department-approved monitoring program to determine if continued reduced monitoring is appropriate. If the department determines a change in the monitoring requirements of the receiving system is appropriate:

     (i) The department shall notify the purveyor of the change in monitoring requirements; and

     (ii) The purveyor shall conduct monitoring as directed by the department.

     (3) Bacteriological.

     (a) The purveyor shall be responsible for collection and submittal of coliform samples from representative points throughout the distribution system. Samples shall be collected after the first service and at regular time intervals each month the system provides water to consumers. Samples shall be collected that represent normal system operating conditions.

     (i) Systems providing disinfection treatment shall, when taking a routine or repeat sample, measure residual disinfectant concentration within the distribution system at the same time and location and comply with the residual disinfection monitoring requirements under WAC 246-290-451.

     (ii) Systems providing disinfection treatment shall assure that disinfectant residual concentrations are measured and recorded on all coliform sample report forms submitted for compliance purposes.

     (b) Coliform monitoring plan.

     (i) The purveyor shall prepare a written coliform monitoring plan and base routine monitoring upon the plan. The plan shall include coliform sample collection sites and a sampling schedule.

     (ii) The purveyor shall:

     (A) Keep the coliform monitoring plan on file with the system and make it available to the department for inspection upon request;

     (B) Revise or expand the plan at any time the plan no longer ensures representative monitoring of the system, or as directed by the department; and

     (C) Submit the plan to the department for review and approval when requested and as part of the water system plan required under WAC 246-290-100.

     (c) Monitoring frequency. The number of required routine coliform samples is based on total population served.

     (i) Purveyors of community systems shall collect and submit for analysis no less than the number of routine samples listed in Table 2 during each calendar month of operation;

     (ii) Unless directed otherwise by the department, purveyors of noncommunity systems shall collect and submit for analysis no less than the number of samples required in Table 2, and no less than required under 40 CFR 141.21. Each month's population shall be based on the average daily population and shall include all residents and nonresidents served during that month. During months when the average daily population served is less than twenty-five, routine sample collection is not required when:

     (A) Using only protected ground water sources;

     (B) No coliform were detected in samples during the previous month; and

     (C) One routine sample has been collected and submitted for analysis during one of the previous two months.

     (iii) Purveyors of systems serving both a resident and a nonresident population shall base their minimum sampling requirement on the total of monthly populations served, both resident and nonresident as determined by the department, but no less than the minimum required in Table 2; and

     (iv) Purveyors of systems with a nonresident population lasting two weeks or less during a month shall sample as directed by the department. Sampling shall be initiated at least two weeks prior to the time service is provided to consumers.

     (v) Purveyors of TNC systems shall not be required to collect routine samples in months where the population served is zero or the system has notified the department of an unscheduled closure.

     (d) Invalid samples. When a coliform sample is determined invalid under WAC 246-290-320 (2)(d), the purveyor shall:

     (i) Not include the sample in the determination of monitoring compliance; and

     (ii) Take follow-up action as defined in WAC 246-290-320 (2)(d).

     (e) The purveyor using a surface water or GWI source shall collect representative source water samples for bacteriological density analysis in accordance with WAC 246-290-664 and 246-290-694 as applicable.

TABLE 2

MINIMUM MONTHLY ROUTINE COLIFORM

SAMPLING REQUIREMENTS

² Noncommunity systems using only protected ground water sources and serving less than 25 individuals, may collect and submit for analysis, one sample every three months.

³ Systems serving populations larger than 1,230,000 shall contact the department for the minimum number of samples required per month.

^*In addition to the provisions of subsection (1)(a) of this section, if a system of this size cannot show evidence of having been subject to a sanitary survey on file with the department, or has been determined to be at risk to bacteriological concerns following a survey, the minimum number of samples required per month may be increased by the department after additional consideration of such factors as monitoring history, compliance record, operational problems, and water quality concerns for the system.

     (4) Inorganic chemical and physical.

     (a) A complete inorganic chemical and physical analysis shall consist of the primary and secondary chemical and physical substances.

     (i) Primary chemical and physical substances are antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, nickel, nitrate (as N), nitrite (as N), selenium, sodium, thallium, and for unfiltered surface water, turbidity. (Except that the MCL for arsenic under WAC 246-290-310 does not apply to TNC systems.)

     (ii) Secondary chemical and physical substances are chloride, color, hardness, iron, manganese, specific conductivity, silver, sulfate, total dissolved solids*, and zinc.

*	Required only when specific conductivity exceeds seven hundred micromhos/centimeter.

     (b) Purveyors shall monitor for all primary and secondary chemical and physical substances identified in Table 4 and Table 5. Samples shall be collected in accordance with the monitoring requirements referenced in 40 CFR 141.23 introductory text, 141.23(a) through 141.23(j), excluding (i)(2), and 40 CFR 143.4, except for composite samples for systems serving less than three thousand three hundred one persons. For these systems, compositing among different systems may be allowed if the systems are owned or operated by a department-approved satellite management agency.

     (c) Samples required by this subsection shall be taken at designated locations in accordance with 40 CFR 141.23(a) through 141.23(j), excluding (i)(2), and 40 CFR 143.4, and Table 3 herein.

     (i) Wellfield samples shall be allowed from department designated wellfields; and

     (ii) In accordance with 40 CFR 141.23 (a)(3), alternate sampling locations may be used if approved by the department. The process for determining these alternate sites is described in department guidance. Purveyors of community and NTNC systems may ask the department to approve an alternate sampling location for multiple sources within a single system that are blended prior to entry to the distribution system. Alternate sampling plans shall address the following:

     (A) Source vulnerability;

     (B) Individual source characteristics;

     (C) Previous water quality information;

     (D) Status of monitoring waiver applications; and

     (E) Other information deemed necessary by the department.

     (d) Composite samples:

     (i) In accordance with CFR 141.23 (a)(4), purveyors may ask the certified lab to composite samples representing as many as five individual samples from within one system. Sampling procedures and protocols are outlined in department guidance; and

     (ii) For systems serving a population of less than three thousand three hundred one, the department may approve composite sampling between systems when those systems are part of an approved satellite management agency.

     (e) When the purveyor provides treatment for one or more inorganic chemical or physical contaminants, the department may require the purveyor to sample before and after treatment. The department shall notify the purveyor if and when this additional source sampling is required.

     (f) Inorganic monitoring plans.

     (i) Purveyors of community and NTNC systems shall prepare an inorganic chemical monitoring plan and base routine monitoring on the plan.

     (ii) The purveyor shall:

     (A) Keep the monitoring plan on file with the system and make it available to the department for inspection upon request;

     (B) Revise or expand the plan at any time the plan no longer reflects the monitoring requirements, procedures or sampling locations, or as directed by the department; and

     (C) Submit the plan to the department for review and approval when requested and as part of the water system plan required under WAC 246-290-100.

     (g) Monitoring waivers.

     (i) Purveyors may request in writing, a monitoring waiver from the department for any nonnitrate/nitrite inorganic chemical and physical monitoring requirements identified in this chapter.

     (ii) Purveyors requesting a monitoring waiver shall comply with applicable subsections of 40 CFR 141.23 (b)(3), 141.23 (c)(3), and 141.40 (n)(4).

     (iii) Purveyors shall update and resubmit requests for waiver renewals as applicable during each compliance cycle or period or more frequently as directed by the department.

     (iv) Failure to provide complete and accurate information in the waiver application shall be grounds for denial of the monitoring waiver.

     (h) The department may require the purveyor to repeat sample for confirmation of results.

     (i) Purveyors with emergency and seasonal sources shall monitor those sources when they are in use.

     (5) Lead and copper. Monitoring for lead and copper shall be conducted in accordance with 40 CFR 141.86 (a) - (f), 141.87, and 141.88.

     (6) Trihalomethanes (THMs).

     (a) Purveyors of community systems serving at least ten thousand people and providing water treated with chlorine or other halogenated disinfectant shall monitor as follows:

     (i) Ground water sources. Until December 31, 2003, the purveyor shall collect one sample from each treated ground water source every twelve months. This sample shall be taken at the source before treatment and analyzed for maximum total trihalomethane potential (MTTP). The purveyor may receive approval from the department for an alternate sample location if it would provide essentially the same information as an MTTP analysis regarding the levels of THMs that the consumers are, or could potentially be, exposed to in the drinking water. Beginning January 1, 2004, systems that add a chemical disinfectant shall meet the monitoring requirements in subsection (7) of this section.

     (ii) Surface water sources. The purveyor shall meet the monitoring requirements in subsection (7) of this section.

     (iii) Purchased surface water sources. Purveyors of consecutive systems that add a chemical disinfectant to either the surface water they purchase, or to additional ground water supplies they use, shall meet the monitoring requirements in subsection (7) of this section.

     (b) Until December 31, 2003, purveyors of community systems shall monitor for TTHM(s) when serving a population less than ten thousand and providing surface water treated with chlorine or other halogenated disinfectant. The purveyor shall collect one water sample per treated source every three months for one year. The sample shall be taken at the extreme end of the distribution system and analyzed for TTHM(s). After the first year, the purveyor shall monitor surface water sources every thirty-six months. Beginning January 1, 2004, systems that add a chemical disinfectant shall meet the monitoring requirements in subsection (7) of this section.

     (c) Until December 31, 2003, purveyors of community systems shall monitor for TTHM(s) when serving less than ten thousand people and purchasing surface water treated with chlorine or other halogenated disinfectant or adding a halogenated disinfectant after purchase. The purveyor shall collect one water sample every three months at the extreme end of the distribution system or at a department-acceptable location. The sample shall be analyzed for TTHM(s). After the first year, the purveyor shall monitor every thirty-six months. Beginning January 1, 2004, systems that add a chemical disinfectant to either the surface water they purchase, or to additional ground water supplies they use, shall meet the monitoring requirements in subsection (7) of this section.

     (d) After December 31, 2003, subsection (6) of this section no longer applies to any public water system.

     (7) Disinfection by-products (DBP), disinfectant residuals, and disinfection by-product precursors (DBPP). Purveyors of community and NTNC systems providing water treated with chemical disinfectants and TNC systems using chlorine dioxide shall monitor as follows:

     (a) General requirements.

     (i) Systems shall collect samples during normal operating conditions.

     (ii) All monitoring shall be conducted in accordance with the analytical requirements in 40 CFR 141.131.

     (iii) Systems may consider multiple wells drawing from a single aquifer as one treatment plant for determining the minimum number of TTHM and HAA5 samples required, with department approval in accordance with department guidance.

     (iv) Systems required to monitor under this subsection shall prepare and implement a monitoring plan in accordance with 40 CFR 141.132(f).

     (A) Community and NTNC surface water systems that add a chemical disinfectant and serve at least ten thousand people shall submit a monitoring plan to the department.

     (B) Community and NTNC surface water systems that add a chemical disinfectant and serve less than ten thousand people, but more than three thousand three hundred people, shall submit a monitoring plan to the department by April 10, 2004.

     (C) The department may require submittal of a monitoring plan from systems not specified in subsection (7)(a)(iv)(A) or (B) of this section, and may require revision of any monitoring plan.

     (D) Failure to monitor will be treated as a violation for the entire period covered by the annual average where compliance is based on a running annual average of monthly or quarterly samples or averages and the systems' failure to monitor makes it impossible to determine compliance with MCL's or MRDL's.

     (b) Disinfection by-products - Community and NTNC systems only.

     (i) Compliance dates.

     (A) A system that is installing Granular Activated Carbon (GAC) with a minimum ten minutes of empty bed contact time (GAC10) or membrane technology to comply with WAC 246-290-310(5) may apply to the department for an extension of time to comply with this subsection. The extension may not go beyond December 31, 2003.

     (B) Surface water systems that serve less than ten thousand people, or systems using only ground water, and that add a chemical disinfectant, including, but not limited to, chlorine, chloramines, chlorine dioxide, and/or ozone, shall comply with the applicable requirements of this subsection beginning January 1, 2004.

     (ii) TTHMs and HAA5.

     (A) Systems shall monitor for TTHMs and HAA5 in accordance with 40 CFR 141.132 (b)(1)(i).

     (B) With department approval, systems may reduce monitoring in accordance with 40 CFR 141.132 (b)(1)(ii).

     (C) Systems on department-approved reduced monitoring schedules may be required to return to routine monitoring, or initiate increased monitoring in accordance with 40 CFR 141.132 (b)(1)(iii).

     (D) The department may return systems on increased monitoring to routine monitoring if, after one year, annual average results for TTHMs and HAA5 are less than or equal to 0.060 mg/L and 0.045 mg/L, respectively, or monitoring results are consistently below the MCLs indicating that increased monitoring is no longer necessary.

     (iii) Chlorite - Only systems that use chlorine dioxide.

     (A) Systems using chlorine dioxide shall conduct daily and monthly monitoring in accordance with 40 CFR 141.132 (b)(2)(i) and additional chlorite monitoring in accordance with 40 CFR 141.132 (b)(2)(ii).

     (B) With department approval, monthly monitoring may be reduced in accordance with 40 CFR 141.132 (b)(2)(iii)(B). Daily monitoring at entry to distribution required by 40 CFR 141.132 (b)(2)(i)(A) may not be reduced.

     (iv) Bromate - Only systems that use ozone.

     (A) Systems using ozone for disinfection or oxidation must conduct bromate monitoring in accordance with 40 CFR 141.132 (b)(3)(i).

     (B) With department approval, monthly bromate monitoring may be reduced to once per quarter, in accordance with the provisions and requirements of 40 CFR 141.132 (b)(3)(ii) and 40 CFR 141.132(e).

     (c) Disinfectant residuals.

     (i) Compliance dates.

     (A) Community and NTNC surface water systems that add a chemical disinfectant, including, but not limited to, chlorine, chloramines, chlorine dioxide, and/or ozone, and serve less than ten thousand people, or systems using only ground water, shall comply with the applicable requirements of this section beginning January 1, 2004.

     (B) TNC surface water systems that add chlorine dioxide as a disinfectant or oxidant, and serve less than ten thousand people, or systems using only ground water, shall comply with the chlorine dioxide MRDL beginning January 1, 2004.

     (ii) Chlorine and chloramines. Systems that use chlorine or chloramines shall monitor and record the residual disinfectant level in the distribution system in accordance with WAC 246-290-451(6), 246-290-664 (6)(a), or 246-290-694 (8)(a).

     (iii) Chlorine dioxide. Community, NTNC, or TNC systems that use chlorine dioxide shall monitor in accordance with 40 CFR 141.132 (c)(2) and record results.

     (d) Disinfection by-product precursors.

     (i) Compliance dates.

     Community and NTNC surface water systems serving less than ten thousand people using conventional filtration that employs sedimentation shall comply with the applicable requirements of this subsection beginning January 1, 2004.

     (ii) Surface water systems that use conventional filtration with sedimentation shall monitor in accordance with 40 CFR 141.132(d), and meet the requirements of 40 CFR 141.135.

     (8) Organic chemicals.

     (a) Purveyors of community and NTNC water systems shall comply with monitoring requirements in accordance with 40 CFR 141.24 (a) - (d), 141.24 (f)(1) - (f)(15), 141.24 (f)(18) - (19), 141.24 (f)(21), 141.24 (g)(1) - (9), 141.24 (g)(12) - (14), 141.24 (h)(1) - (11), 141.24 (h)(14) - (17), 141.40(a), 141.40(d), and 141.40(e).

     (b) Sampling locations shall be as defined in 40 CFR 141.24(f), 141.24(g), 141.24(h), 141.40(b) and 141.40(c).

     (i) Wellfield samples shall be allowed from department designated wellfields; and

     (ii) In accordance with 40 CFR 141.24 (f)(3) and 141.24 (h)(3), alternate sampling locations may be allowed if approved by the department. These alternate locations are described in department guidance. Purveyors may ask the department to approve an alternate sampling location for multiple sources within a single system that are blended prior to entry to the distribution system. The alternate sampling location shall consider the following:

     (A) Source vulnerability;

     (B) An updated organic monitoring plan showing location of all sources with current and proposed sampling locations;

     (C) Individual source characteristics;

     (D) Previous water quality information;

     (E) Status of monitoring waiver applications; and

     (F) Other information deemed necessary by the department.

     (c) Composite samples:

     (i) Purveyors may ask the certified lab to composite samples representing as many as five individual samples from within one system. Sampling procedures and protocols are outlined in department guidance;

     (ii) For systems serving a population of less than three thousand three hundred one, the department may approve composite sampling between systems when those systems are part of an approved satellite management agency.

     (d) The department may require the purveyor to sample both before and after treatment for one or more organic contaminants. The department shall notify the purveyor if and when this additional source sampling is required.

     (e) Organic chemical monitoring plans.

     (i) Purveyors of community and NTNC systems shall prepare an organic chemical monitoring plan and base routine monitoring on the plan.

     (ii) The purveyor shall:

     (A) Keep the monitoring plan on file with the system and make it available to the department for inspection upon request;

     (B) Revise or expand the plan at any time the plan no longer reflects the monitoring requirements, procedures or sampling locations, or as directed by the department; and

     (C) Submit the plan to the department for review and approval when requested and as part of the water system plan required under WAC 246-290-100.

     (f) Monitoring waivers.

     (i) Purveyors may request in writing, a monitoring waiver from the department for any organic monitoring requirement except those relating to unregulated VOCs;

     (ii) Purveyors requesting a monitoring waiver shall comply with 40 CFR 141.24 (f)(7), 141.24 (f)(10), 141.24 (h)(6), 141.24 (h)(7) or 141.40 (n)(4);

     (iii) Purveyors shall update and resubmit requests for waiver renewals as directed by the department; and

     (iv) Failure to provide complete and accurate information in the waiver application shall be grounds for denial of the monitoring waiver.

     (g) Purveyors with emergency and seasonal sources shall monitor those sources under the applicable requirements of this section when they are actively providing water to consumers.

     (9) Unregulated chemicals.

     (a) Unregulated inorganic contaminants. Purveyors of community and NTNC systems shall:

     (i) Monitor for the unregulated inorganic chemicals listed in 40 CFR 141.40 (n)(12);

     (ii) Comply with monitoring methods, frequencies, and sampling locations in accordance with 40 CFR 141.40 (n)(2) through 141.40 (n)(9) and 141.40 (n)(12); and

     (iii) Apply in writing for a monitoring waiver according to the conditions outlined in 40 CFR 141.40 (n)(3), and the departmental procedures described in subsection (8)(f) of this section.

     (b) Unregulated VOCs. Purveyors shall:

     (i) Monitor in accordance with 40 CFR 141.40(e) and 141.40(j);

     (ii) Comply with monitoring methods, frequency and sampling locations in accordance with 40 CFR 141.40(a) through 141.40(d), 141.40(g) and 141.40(i); and

     (iii) Perform repeat monitoring for these compounds in accordance with 40 CFR 141.40(l).

     (c) Unregulated SOCs. Purveyors shall:

     (i) Monitor for the unregulated SOCs listed in 40 CFR 141.40 (n)(11); and

     (ii) Comply with monitoring methods, frequencies, and sampling locations in accordance with 40 CFR 141.40 (n)(1) through 141.40 (n)(9).

     Purveyors may request that the department defer this monitoring if a system has less than one hundred fifty service connections.

     (d) Purveyors with emergency and seasonal sources shall monitor those sources under the applicable requirements of this section whenever they are actively providing water to consumers.

     (10) Radionuclides. Monitoring for radionuclides shall be conducted in accordance with 40 CFR 141.26.

     (11) Other substances.

     On the basis of public health concerns, the department may require the purveyor to monitor for additional substances.

TABLE 3

MONITORING LOCATION

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-300, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-300, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-300, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-300, filed 3/25/93, effective 4/25/93; 92-04-070 (Order 241B), § 246-290-300, filed 2/4/92, effective 3/6/92. Statutory Authority: Chapter 43.20 RCW. 91-07-031 (Order 150B), § 246-290-300, filed 3/15/91, effective 4/15/91. Statutory Authority: RCW 43.20.050. 91-02-051 (Order 124B), recodified as § 246-290-300, filed 12/27/90, effective 1/31/91. Statutory Authority: P.L. 99-339. 89-21-020 (Order 336), § 248-54-165, filed 10/10/89, effective 11/10/89. Statutory Authority: RCW 34.04.045. 88-05-057 (Order 307), § 248-54-165, filed 2/17/88. Statutory Authority: RCW 43.20.050. 83-19-002 (Order 266), § 248-54-165, filed 9/8/83.]

     (a) The purveyor shall be responsible for complying with the standards of water quality identified in this section. If a substance exceeds its maximum contaminant level (MCL) or its maximum residual disinfectant level (MRDL), the purveyor shall take follow-up action in accordance with WAC 246-290-320.

     (b) When enforcing the standards described under this section, the department shall enforce compliance with the primary standards as its first priority.

     (2) Bacteriological.

     (a) MCLs under this subsection shall be considered primary standards.

     (b) Notwithstanding subsection (1) of this section, if coliform presence is detected in any sample, the purveyor shall take follow-up action in accordance with WAC 246-290-320(2).

     (c) Acute MCL. An acute MCL for coliform bacteria occurs when there is:

     (i) Fecal coliform presence in a repeat sample;

     (ii) E. coli presence in a repeat sample; or

     (iii) Coliform presence in any repeat samples collected as a follow-up to a sample with fecal coliform or E. coli presence.

Note:

For the purposes of the public notification requirements in Part 7, Subpart A of this chapter, an acute MCL is a violation that requires Tier 1 public notification.

     (d) Nonacute MCL. A nonacute MCL for coliform bacteria occurs when:

     (i) Systems taking less than forty routine samples during the month have more than one sample with coliform presence; or

     (ii) Systems taking forty or more routine samples during the month have more than 5.0 percent with coliform presence.

     (e) MCL compliance. The purveyor shall determine compliance with the coliform MCL for each month the system provides drinking water to the public. In determining MCL compliance, the purveyor shall:

     (i) Include:

     (A) Routine samples; and

     (B) Repeat samples.

     (ii) Not include:

     (A) Samples invalidated under WAC 246-290-320 (2)(d); and

     (B) Special purpose samples.

     (3) Inorganic chemical and physical.

     (a) The primary and secondary MCLs are listed in Table 4 and 5:

TABLE 4

INORGANIC CHEMICAL CHARACTERISTICS

Note*	Does not apply to TNC systems.
	With regard to community and NTNC water systems, new systems or systems that use a new source of water, certified as complete in accordance with WAC 246-290-120(5) after January 22, 2004, must demonstrate compliance with this MCL within a period of time specified by the department.
	With regard to existing community and NTNC water systems, this arsenic MCL is effective January 23, 2006, for the purpose of compliance. Until that time, the MCL is 0.05 mg/L.

Note**

Although the state board of health has not established MCLs for copper, lead, and sodium, there is sufficient public health significance connected with copper, lead, and sodium levels to require inclusion in inorganic chemical and physical source monitoring. For lead and copper, the EPA has established distribution system related levels at which a system is required to consider corrosion control. These levels, called "action levels," are 0.015 mg/L for lead and 1.3 mg/L for copper and are applied to the highest concentration in ten percent of all samples collected from the distribution system. The EPA has also established a recommended level of twenty mg/L for sodium as a level of concern for those consumers that may be restricted for daily sodium intake in their diets.

TABLE 5

PHYSICAL CHARACTERISTICS

     (iii) If a sample result is less than the detection limit, zero will be used to calculate the running annual average.

     (4) Trihalomethanes.

     (a) The department shall consider standards under this subsection primary standards.

     (b) The MCL for total trihalomethanes (TTHMs) is 0.10 mg/L calculated on the basis of a running annual average of quarterly samples. The concentrations of each of the trihalomethane compounds (trichloromethane, dibromochloromethane, bromodichloromethane, and tribromomethane) are totaled to determine the TTHM level.

     (c) There is no MCL for maximum total trihalomethane potential (MTTP). When the MTTP value exceeds 0.10 mg/L, the purveyor shall follow up as described under WAC 246-290-320(6).

     (d) The MCL for total trihalomethanes in this subsection applies only to monitoring required under WAC 246-290-300(6). After December 31, 2003, this section no longer applies to any public water system.

     (5) Disinfection by-products.

     (a) The department shall consider standards under this subsection as primary standards. The MCLs in this subsection apply to monitoring required by WAC 246-290-300(7).

     (b) The MCLs for disinfection by-products are as follows:

Disinfection By-Product	MCL (mg/L)
Total Trihalomethanes (TTHMs)		0.080
Haloacetic acids (five) (HAA5)		0.060
Bromate		0.010
Chlorite		1.0

     (c) Whether a system has exceeded MCLs shall be determined in accordance with 40 CFR 141.133.

     (6) Disinfectant residuals.

     (a) The department shall consider standards under this subsection primary standards. The MRDLs in this subsection apply to monitoring required by WAC 246-290-300(7).

     (b) The MRDL for disinfectants is as follows:

Disinfectant Residual	MRDL (mg/L)
Chlorine		4.0 (as C12)
Chloramines		4.0 (as C12)
Chlorine Dioxide		0.8 (as C1O2)

     (c) Whether a system has exceeded MRDLs shall be determined in accordance with 40 CFR 141.133.

     (7) Radionuclides.

     (a) The department shall consider standards under this subsection primary standards.

     (b) The MCLs for radium-226 and radium-228, gross alpha particle activity, beta particle and photon radioactivity, and uranium shall be as listed in 40 CFR 141.66.

     (8) Organic chemicals.

     (a) The department shall consider standards under this subsection primary standards.

     (b) VOCs.

     (i) The MCLs for VOCs shall be as listed in 40 CFR 141.61(a).

     (ii) The department shall determine compliance with this subsection based on compliance with 40 CFR 141.24(f).

     (c) SOCs.

     (i) MCLs for SOCs shall be as listed in 40 CFR 141.61(c).

     (ii) The department shall determine compliance with this subsection based on compliance with 40 CFR 141.24(h).

     (9) Other chemicals.

     (a) The state board of health shall determine maximum contaminant levels for any additional substances.

     (b) Purveyors may be directed by the department to comply with state advisory levels (SALs) for contaminants that do not have a MCL established in chapter 246-290 WAC. SALs shall be:

     (i) MCLs that have been promulgated by the EPA, but which have not yet been adopted by the state board of health; or

     (ii) State board of health adopted levels for substances recommended by the department and not having an EPA established MCL. A listing of these may be found in the department document titled Procedures and References for the Determination of State Advisory Levels for Drinking Water Contaminants dated June 1996, that has been approved by the state board of health and is available.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-310, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-310, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-310, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-310, filed 3/25/93, effective 4/25/93; 92-04-070 (Order 241B), § 246-290-310, filed 2/4/92, effective 3/6/92. Statutory Authority: Chapter 43.20 RCW. 91-07-031 (Order 150B), § 246-290-310, filed 3/15/91, effective 4/15/91. Statutory Authority: RCW 43.20.050. 91-02-051 (Order 124B), recodified as § 246-290-310, filed 12/27/90, effective 1/31/91. Statutory Authority: P.L. 99-339. 89-21-020 (Order 336), § 248-54-175, filed 10/10/89, effective 11/10/89. Statutory Authority: RCW 34.04.045. 88-05-057 (Order 307), § 248-54-175, filed 2/17/88. Statutory Authority: RCW 43.20.050. 83-19-002 (Order 266), § 248-54-175, filed 9/8/83.]

     (a) When an MCL or MRDL violation or exceedance occurs, the purveyor shall take follow-up action as described in this section.

     (b) When a primary standard violation occurs, the purveyor shall:

     (i) Notify the department in accordance with WAC 246-290-480;

     (ii) Notify the consumers served by the system and the owner or operator of any consecutive system served in accordance with 40 CFR 141.201 through 208, and Part 7, Subpart A of this chapter;

     (iii) Determine the cause of the contamination; and

     (iv) Take action as directed by the department.

     (c) When a secondary standard violation occurs, the purveyor shall notify the department and take action as directed by the department.

     (d) The department may require additional sampling for confirmation of results.

     (2) Bacteriological.

     (a) When coliform bacteria are present in any sample and the sample is not invalidated under (d) of this subsection, the purveyor shall ensure the following actions are taken:

     (i) The sample is analyzed for fecal coliform or E. coli. When a sample with a coliform presence is not analyzed for E. coli or fecal coliforms, the sample shall be considered as having a fecal coliform presence for MCL compliance purposes;

     (ii) Repeat samples are collected in accordance with (b) of this subsection;

     (iii) The department is notified in accordance with WAC 246-290-480; and

     (iv) The cause of the coliform presence is determined and corrected.

     (b) Repeat samples.

     (i) The purveyor shall collect repeat samples in order to confirm the original sample results and to determine the cause of the coliform presence. Additional treatment, such as batch or shock chlorination, shall not be instituted prior to the collection of repeat samples unless prior authorization by the department is given. Following collection of repeat samples, and before the analytical results are known, there may be a need to provide interim precautionary treatment or other means to insure public health protection. The purveyor shall contact the department to determine the best interim approach in this situation.

     (ii) The purveyor shall collect and submit for analysis a set of repeat samples for every sample in which the presence of coliforms is detected. A set of repeat coliform samples consists of:

     (A) Four repeat samples for systems collecting one routine coliform sample each month; or

     (B) Three repeat samples for all systems collecting more than one routine coliform sample each month.

     (iii) The purveyor shall collect repeat sample sets according to Table 7;

     (iv) The purveyor shall collect one set of repeat samples for each sample with a coliform presence. All samples in a set of repeat samples shall be collected on the same day and submitted for analysis within twenty-four hours after notification by the laboratory of a coliform presence, or as directed by the department.

     (v) When repeat samples have coliform presence, the purveyor shall:

     (A) Contact the department and collect a minimum of one additional set of repeat samples as directed by the department; or

     (B) Collect one additional set of repeat samples for each sample where coliform presence was detected.

     (vi) The purveyor of a system providing water to consumers via a single service shall collect repeat samples from the same location as the sample with a coliform presence. The set of repeat samples shall be collected:

     (A) On the same collection date;

     (B) Over consecutive days with one sample collected each day until the required samples in the set of repeat samples are collected; or

     (C) As directed by the department.

     (vii) If a sample with a coliform presence was collected from the first two or last two active services, the purveyor shall monitor as directed by the department;

     (viii) The purveyor may change a previously submitted routine sample to a sample in a set of repeat samples when the purveyor:

     (A) Collects the sample within five adjacent service connections of the location from which the initial sample with a coliform presence was collected;

     (B) Collects the sample after the initial sample with a coliform presence was submitted for analysis;

     (C) Collects the sample on the same day as other samples in the set of repeat samples, except under (b)(iv) of this subsection; and

     (D) Requests and receives approval from the department for the change.

     (ix) The department may determine that sets of repeat samples specified under this subsection are not necessary during a month when a nonacute coliform MCL violation is determined for the system.

Table 7

REPEAT SAMPLE REQUIREMENTS

     (c) Monitoring frequency following a coliform presence. Systems having one or more coliform presence samples that were not invalidated during the previous month shall collect and submit for analysis the minimum number of samples shown in the last column of Table 2.

     (i) The purveyor may obtain a reduction in the monitoring frequency requirement when one or more samples with a coliform presence were collected during the previous month, if the purveyor proves to the satisfaction of the department;

     (A) The cause of the sample with a coliform presence; and

     (B) The problem is corrected before the end of the next month the system provides water to the public.

     (ii) If the monitoring frequency requirement is reduced, the purveyor shall collect and submit at least the minimum number of samples required when no samples with a coliform presence were collected during the previous month.

     (d) Invalid samples. Coliform samples may be determined to be invalid under any of the following conditions:

     (i) A certified laboratory determines that the sample results show:

     (A) Multiple tube technique cultures that are turbid without appropriate gas production;

     (B) Presence-absence technique cultures that are turbid in the absence of an acid reaction;

     (C) Occurrence of confluent growth patterns or growth of TNTC (too numerous to count) colonies without a surface sheen using a membrane filter analytic technique;

     (ii) The analyzing laboratory determines there is excess debris in the sample.

     (iii) The analyzing laboratory establishes that improper sample collection or analysis occurred;

     (iv) The department determines that a nondistribution system problem has occurred as indicated by:

     (A) All samples in the set of repeat samples collected at the same location, including households, as the original coliform presence sample also are coliform presence; and

     (B) All other samples from different locations (households, etc.) in the set of repeat samples are free of coliform.

     (v) The department determines a coliform presence result is due to a circumstance or condition that does not reflect water quality in the distribution system.

     (e) Follow-up action when an invalid sample is determined. The purveyor shall take the following action when a coliform sample is determined to be invalid:

     (i) Collect and submit for analysis an additional coliform sample from the same location as each invalid sample within twenty-four hours of notification of the invalid sample; or

     (ii) In the event that it is determined that the invalid sample resulted from circumstances or conditions not reflective of distribution system water quality, collect a set of samples in accordance with Table 7; and

     (iii) Collect and submit for analysis samples as directed by the department.

     (f) Invalidated samples shall not be included in determination of the sample collection requirement for compliance with this chapter.

     (3) Inorganic chemical and physical follow-up monitoring shall be conducted in accordance with the following:

     (a) For nonnitrate/nitrite primary inorganic chemicals, 40 CFR 141.23 (a)(4), 141.23 (b)(8), 141.23 (c)(7), 141.23 (c)(9), 141.23 (f)(1), 141.23(g), 141.23(m) and 141.23(n);

     (b) For nitrate, 40 CFR 141.23 (a)(4), 141.23 (d)(2), 141.23 (d)(3), 141.23 (f)(2), 141.23(g), 141.23(m), 141.23(n), and 141.23(o);

     (c) For nitrite, 40 CFR 141.23 (a)(4), 141.23 (e)(3), 141.23 (f)(2), and 141.23(g); or

     (d) The purveyor of any public water system providing service that has secondary inorganic MCL exceedances shall take follow-up action as required by the department. Follow-up action shall be commensurate with the degree of consumer acceptance of the water quality and their willingness to bear the costs of meeting the secondary standard. For new community water systems and new nontransient noncommunity water systems without active consumers, treatment for secondary contaminant MCL exceedances will be required.

     (4) Lead and copper follow-up monitoring shall be conducted in accordance with 40 CFR 141.85(d), 141.86 (d)(2), 141.86 (d)(3), 141.87(d) and 141.88(b) through 141.88(d).

     (5) Turbidity.

     Purveyors monitoring turbidity in accordance with Part 6 of this chapter shall provide follow-up in accordance with WAC 246-290-634.

     (6) Trihalomethanes. For public water systems subject to WAC 246-290-300(6):

     (a) When the average of all samples taken during any twelve-month period exceeds the MCL for total trihalomethanes as referenced in WAC 246-290-310 (4)(b), the violation is confirmed and the purveyor shall take corrective action as required by the department, and consistent with 40 CFR 141.30 (b)(3). When the maximum trihalomethane potential (MTTP) result is equal to or greater than 0.10 mg/L and the result is confirmed by a promptly collected repeat sample, the purveyor shall provide for additional monitoring and take action as directed by the department.

     (7) Organic chemicals. Follow-up monitoring shall be conducted in accordance with the following:

     (a) For VOCs, 40 CFR 141.24 (f)(11) through 141.24 (f)(15), and 141.24 (f)(22); or

     (b) For SOCs, 40 CFR 141.24(b), 141.24(c) and 141.24 (h)(7) through 141.24 (h)(11), and 141.24 (h)(20).

     (8) Unregulated inorganic and organic chemicals.

     (a) Follow-up monitoring shall be conducted in accordance with 40 CFR 141.40 (n)(8) and 141.40 (n)(9).

     (b) When an unregulated chemical is verified at a concentration above the detection limit, the purveyor shall:

     (i) Submit the sample analysis results to the department within seven days of receipt from the laboratory; and

     (ii) Sample the source a minimum of once every three months for one year and then annually thereafter during the three-month period when the highest previous measurement occurred.

     (c) If the department determines that an unregulated chemical is verified at a level greater than a SAL, the department shall notify the purveyor in writing. The purveyor shall repeat sample the source as soon as possible after initial department notice that a SAL has been exceeded. The purveyor shall submit the analysis results to the department within seven days of receipt from the laboratory. If any repeat sample confirms that a SAL has been exceeded, the purveyor shall:

     (i) Provide consumer information in accordance with Part 7, Subpart A of this chapter;

     (ii) Investigate the cause of the contamination; and

     (iii) Take follow-up or corrective action as required by the department.

     (d) The department may reduce the purveyor's monitoring requirement for a source detecting an unregulated chemical if the source has been monitored annually for at least three years, and all analysis results are less than the SAL.

     (9) Radionuclide follow-up monitoring shall be conducted in accordance with 40 CFR 141.26 (a)(2)(iv), 141.26 (a)(3)(ii) through (v), 141.26 (a)(4), 141.26 (b)(6), and 141.26 (c)(5).

     (10) The department shall determine the purveyor's follow-up action when a substance not included in this chapter is detected.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-320, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-320, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-320, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-320, filed 3/25/93, effective 4/25/93; 92-04-070 (Order 241B), § 246-290-320, filed 2/4/92, effective 3/6/92. Statutory Authority: Chapter 43.20 RCW. 91-07-031 (Order 150B), § 246-290-320, filed 3/15/91, effective 4/15/91. Statutory Authority: RCW 43.20.050. 91-02-051 (Order 124B), recodified as § 246-290-320, filed 12/27/90, effective 1/31/91. Statutory Authority: P.L. 99-339. 89-21-020 (Order 336), § 248-54-185, filed 10/10/89, effective 11/10/89. Statutory Authority: RCW 34.04.045. 88-05-057 (Order 307), § 248-54-185, filed 2/17/88. Statutory Authority: RCW 43.20.050. 83-19-002 (Order 266), § 248-54-185, filed 9/8/83.]

     (1) Beginning in the report due by July 1, 2002, a system which detects arsenic levels above 0.005 mg/L and up to and including ((0.01)) 0.010 mg/L:

     (a) Must include in its report a short informational statement about arsenic, using language such as: While your drinking water meets EPA's standard for arsenic, it does contain low levels of arsenic. EPA's standard balances the current understanding of arsenic's possible health effects against the cost of removing arsenic from drinking water. EPA continues to research the health effects of low levels of arsenic, which is a mineral known to cause cancer in humans at high concentrations and is linked to other health effects such as skin damage and circulatory problems.

     (b) May write its own educational statement, but only in consultation with the department.

     (2) A system which detects nitrate at levels above 5 mg/l, but below the MCL:

     (a) Must include a short informational statement about the impacts of nitrate on children using language such as: Nitrate in drinking water at levels above 10 ppm is a health risk for infants of less than six months of age. High nitrate levels in drinking water can cause blue-baby syndrome. Nitrate levels may rise quickly for short periods of time because of rainfall or agricultural activity. If you are caring for an infant, you should ask for advice from your health care provider.

     (b) May write its own educational statement, but only in consultation with the department.

     (3) Systems which detect lead above the action level in more than five percent, and up to and including ten percent, of homes sampled:

     (a) Must include a short informational statement about the special impact of lead on children using language such as: Infants and young children are typically more vulnerable to lead in drinking water than the general population. It is possible that lead levels at your home may be higher than at other homes in the community as a result of materials used in your home's plumbing. If you are concerned about elevated lead levels in your home's water, you may wish to have your water tested and flush your tap for thirty seconds to two minutes before using tap water. Additional information is available from the Safe Drinking Water Hotline (800-426-4791).

     (b) May write its own educational statement, but only in consultation with the department.

     (4) Community water systems that detect TTHM above 0.080 mg/l, but below the MCL in WAC 246-290-310(4), as an annual average, monitored and calculated under the provisions of WAC 246-290-300(6), must include health effects language prescribed by WAC 246-290-72012.

     (5) Beginning in the report due by July 1, 2002, and ending January 22, 2006, a community water system that detects arsenic above 0.01 mg/L and up to and including 0.05 mg/L must include the arsenic health effects language prescribed in WAC 246-290-72012.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-72010, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.20.050. 00-15-080, § 246-290-72010, filed 7/19/00, effective 8/19/00.]

Contaminant (units)	traditional MCL in mg/L	to convert for CCR, multiply by	MCL in CCR units	MCLG	Major Sources in Drinking Water	Health Effects Language
Microbiological Contaminants
Total Coliform Bacteria	MCL: (systems that collect ≥ 40 samples/ month) 5% of monthly samples are positive; (systems that collect < 40 samples/ month) 1 positive monthly sample		MCL: (systems that collect ≥ 40 samples/ month) 5% of monthly samples are positive; (systems that collect < 40 samples/ month) 1 positive monthly sample	0	Naturally present in the environment	Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially-harmful, bacteria may be present. Coliforms were found in more samples than allowed and this was a warning of potential problems.
Fecal coliform and E. coli	0		0	0	Human and animal fecal waste	Fecal coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, some of the elderly, and people with severely-compromised immune systems.
Total organic carbon (ppm)	TT	-	TT	n/a	Naturally present in the environment	Total organic carbon (TOC) has no health effects. However, total organic carbon provides a medium for the formation of disinfection by-products. These by-products include trihalomethanes (THMs) and haloacetic acids (HAAs). Drinking water containing these by-products in excess of the MCL may lead to adverse health effects, liver or kidney problems, or nervous system effects, and may lead to an increased risk of getting cancer.
Turbidity (NTU)	TT.	-	TT	n/a	Soil runoff	Turbidity has no health effects. However, turbidity can interfere with disinfection and provide a medium for microbial growth. Turbidity may indicate the presence of disease-causing organisms. These organisms include bacteria, viruses, and parasites that can cause symptoms such as nausea, cramps, diarrhea and associated headaches.
Radioactive Contaminants
Beta/photon emitters (mrem/yr) ((*Effective 12/08/03))	4 mrem/yr	-	4	n/a 0	Decay of natural and man-made deposits	Certain minerals are radioactive and may emit forms of radiation known as photons and beta radiation. Some people who drink water containing beta and photon emitters in excess of the MCL over many years may have an increased risk of getting cancer.
Alpha emitters (pCi/l) ((*Effective 12/08/03))	15 pCi/l	-	15	n/a 0	Erosion of natural deposits	Certain minerals are radioactive and may emit a form of radiation known as alpha radiation. Some people who drink water containing alpha emitters in excess of the MCL over many years may have an increased risk of getting cancer.
Combined radium (pCi/l) ((*Effective 12/08/03))	5 pCi/l	-	5	n/a 0	Erosion of natural deposits	Some people who drink water containing radium 226 or 228 in excess of the MCL over many years may have an increased risk of getting cancer.
Uranium (pCi/l) ((*Effective 12/08/03))	30 micro g/l	-	30	0	Erosion of natural deposits	Some people who drink water containing uranium in excess of the MCL over many years may have an increased risk of getting cancer and kidney toxicity.
Inorganic Contaminants
Antimony (ppb)	.006	1000	6	6	Discharge from petroleum refineries; fire retardants; ceramics; electronics; solder	Some people who drink water containing antimony well in excess of the MCL over many years could experience increases in blood cholesterol and decreases in blood sugar.
Arsenic (ppb) *Effective 1/23/06	.05 ((0.01)) 0.010	1000 1000	50 10	n/a 0	Erosion of natural deposits; Runoff from orchards; Runoff from glass and electronics production wastes	Some people who drink water containing arsenic in excess of the MCL over many years could experience skin damage or problems with their circulatory system, and may have an increased risk of getting cancer.
Asbestos (MFL)	7 MFL	-	7	7	Decay of asbestos cement water mains; Erosion of natural deposits	Some people who drink water containing asbestos in excess of the MCL over many years may have an increased risk of developing benign intestinal polyps.
Barium (ppm)	2	-	2	2	Discharge of drilling wastes; Discharge from metal refineries; Erosion of natural deposits	Some people who drink water containing barium in excess of the MCL over many years could experience an increase in their blood pressure.
Beryllium (ppb)	.004	1000	4	4	Discharge from metal refineries and coal-burning factories; Discharge from electrical, aerospace, and defense industries	Some people who drink water containing beryllium well in excess of the MCL over many years could develop intestinal lesions.
Cadmium (ppb)	.005	1000	5	5	Corrosion of galvanized pipes; Erosion of natural deposits; Discharge from metal refineries; Runoff from waste batteries and paints	Some people who drink water containing cadmium in excess of the MCL over many years could experience kidney damage.
Chromium (ppb)	.1	1000	100	100	Discharge from steel and pulp mills; Erosion of natural deposits	Some people who use water containing chromium well in excess of the MCL over many years could experience allergic dermatitis.
Copper (ppm)	AL = 1.3	-	AL = 1.3	1.3	Corrosion of household plumbing systems; Erosion of natural deposits((; Leaching from wood preservatives))	Copper is an essential nutrient, but some people who drink water containing copper in excess of the action level over a relatively short amount of time could experience gastrointestinal distress. Some people who drink water containing copper in excess of the action level over many years could suffer liver or kidney damage. People with Wilson's Disease should consult their personal doctor.
Cyanide (ppb)	.2	1000	200	200	Discharge from steel/metal factories; Discharge from plastic and fertilizer factories	Some people who drink water containing cyanide well in excess of the MCL over many years could experience nerve damage or problems with their thyroid.
Fluoride (ppm)	4	-	4	4	Erosion of natural deposits; Water additive which promotes strong teeth; Discharge from fertilizer and aluminum factories	Some people who drink water containing fluoride in excess of the MCL over many years could get bone disease, including pain and tenderness of the bones. Fluoride in drinking water at half the MCL or more may cause mottling of children's teeth, usually in children less than nine years old. Mottling, also known as dental fluorosis, may include brown staining and/or pitting of the teeth, and occurs only in developing teeth before they erupt from the gums.
Lead (ppb)	AL = .015	1000	AL = 15	0	Corrosion of household plumbing systems; Erosion of natural deposits	Infants and children who drink water containing lead in excess of the action level could experience delays in their physical or mental development. Children could show slight deficits in attention span and learning abilities. Adults who drink this water over many years could develop kidney problems or high blood pressure.
Mercury [inorganic] (ppb)	.002	1000	2	2	Erosion of natural deposits; Discharge from refineries and factories; Runoff from landfills; Runoff from cropland	Some people who drink water containing inorganic mercury well in excess of the MCL over many years could experience kidney damage.
Nitrate (ppm)	10	-	10	10	Runoff from fertilizer use; Leaching from septic tanks, sewage; Erosion of natural deposits	Infants below the age of six months who drink water containing nitrate in excess of the MCL could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue baby syndrome.
Nitrite (ppm)	1	-	1	1	Runoff from fertilizer use; Leaching from septic tanks, sewage; Erosion of natural deposits	Infants below the age of six months who drink water containing nitrite in excess of the MCL could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue baby syndrome.
Selenium (ppb)	.05	1000	50	50	Discharge from petroleum and metal refineries; Erosion of natural deposits; Discharge from mines	Selenium is an essential nutrient. However, some people who drink water containing selenium in excess of the MCL over many years could experience hair or fingernail losses, numbness in fingers or toes, or problems with their circulation.
Thallium (ppb)	.002	1000	2	0.5	Leaching from ore-processing sites; Discharge from electronics, glass, and drug factories	Some people who drink water containing thallium in excess of the MCL over many years could experience hair loss, changes in their blood, or problems with their kidneys, intestines, or liver.
Synthetic Organic Contaminants including Pesticides and Herbicides
2,4-D (ppb)	.07	1000	70	70	Runoff from herbicide used on row crops	Some people who drink water containing the weed killer 2,4-D well in excess of the MCL over many years could experience problems with their kidneys, liver, or adrenal glands.
2,4,5-TP [Silvex](ppb)	.05	1000	50	50	Residue of banned herbicide	Some people who drink water containing silvex in excess of the MCL over many years could experience liver problems.
Acrylamide	TT	-	TT	0	Added to water during sewage/ wastewater treatment	Some people who drink water containing high levels of acrylamide over a long period of time could have problems with their nervous system or blood, and may have an increased risk of getting cancer.
Alachlor (ppb)	.002	1000	2	0	Runoff from herbicide used on row crops	Some people who drink water containing alachlor in excess of the MCL over many years could have problems with their eyes, liver, kidneys, or spleen, or experience anemia, and may have an increased risk of getting cancer.
Atrazine (ppb)	.003	1000	3	3	Runoff from herbicide used on row crops	Some people who drink water containing atrazine well in excess of the MCL over many years could experience problems with their cardiovascular system or reproductive difficulties.
Benzo(a)pyrene [PAH] (nanograms/l)	.0002	1,000,000	200	0	Leaching from linings of water storage tanks and distribution lines	Some people who drink water containing benzo(a)pyrene in excess of the MCL over many years may experience reproductive difficulties and may have an increased risk of getting cancer.
Carbofuran (ppb)	.04	1000	40	40	Leaching of soil fumigant used on rice and alfalfa	Some people who drink water containing carbofuran in excess of the MCL over many years could experience problems with their blood, or nervous or reproductive systems.
Chlordane (ppb)	.002	1000	2	0	Residue of banned termiticide	Some people who drink water containing chlordane in excess of the MCL over many years could experience problems with their liver or nervous system, and may have an increased risk of getting cancer.
Dalapon (ppb)	.2	1000	200	200	Runoff from herbicide used on rights of way	Some people who drink water containing dalapon well in excess of the MCL over many years could experience minor kidney changes.
Di(2-ethylhexyl) adipate (ppb)	.4	1000	400	400	Discharge from chemical factories	Some people who drink water containing di (2-ethylhexyl) adipate well in excess of the MCL over many years could experience ((general)) toxic effects or reproductive difficulties.
Di(2-ethylhexyl) phthalate (ppb)	.006	1000	6	0	Discharge from rubber and chemical factories	Some people who drink water containing di (2-ethylhexyl) phthalate well in excess of the MCL over many years may have problems with their liver, or experience reproductive difficulties, and may have an increased risk of getting cancer.
Dibromochloropropane (ppt)	.0002	1,000,000	200	0	Runoff/leaching from soil fumigant used on soybeans, cotton, pineapples, and orchards	Some people who drink water containing DBCP in excess of the MCL over many years could experience reproductive problems and may have an increased risk of getting cancer.
Dinoseb (ppb)	.007	1000	7	7	Runoff from herbicide used on soybeans and vegetables	Some people who drink water containing dinoseb well in excess of the MCL over many years could experience reproductive difficulties.
Diquat (ppb)	.02	1000	20	20	Runoff from herbicide use	Some people who drink water containing diquat in excess of the MCL over many years could get cataracts.
Dioxin [2,3,7,8-TCDD] (ppq)	.00000003	1,000,000,000	30	0	Emissions from waste incineration and other combustion; Discharge from chemical factories	Some people who drink water containing dioxin in excess of the MCL over many years could experience reproductive difficulties and may have an increased risk of getting cancer.
Endothall (ppb)	.1	1000	100	100	Runoff from herbicide use	Some people who drink water containing endothall in excess of the MCL over many years could experience problems with their stomach or intestines.
Endrin (ppb)	.002	1000	2	2	Residue of banned insecticide	Some people who drink water containing endrin in excess of the MCL over many years could experience liver problems.
Epichlorohydrin	TT	-	TT	0	Discharge from industrial chemical factories; An impurity of some water treatment chemicals	Some people who drink water containing high levels of epichlorohydrin over a long period of time could experience stomach problems, and may have an increased risk of getting cancer.
Ethylene dibromide (ppt)	.00005	1,000,000	50	0	Discharge from petroleum refineries	Some people who drink water containing ethylene dibromide in excess of the MCL over many years could experience problems with their liver, stomach, reproductive system, or kidneys, and may have an increased risk of getting cancer.
Glyphosate (ppb)	.7	1000	700	700	Runoff from herbicide use	Some people who drink water containing glyphosate in excess of the MCL over many years could experience problems with their kidneys or reproductive difficulties.
Heptachlor (ppt)	.0004	1,000,000	400	0	Residue of banned pesticide	Some people who drink water containing heptachlor in excess of the MCL over many years could experience liver damage and may have an increased risk of getting cancer.
Heptachlor epoxide (ppt)	.0002	1,000,000	200	0	Breakdown of heptachlor	Some people who drink water containing heptachlor epoxide in excess of the MCL over many years could experience liver damage, and may have an increased risk of getting cancer.
Hexachlorobenzene (ppb)	.001	1000	1	0	Discharge from metal refineries and agricultural chemical factories	Some people who drink water containing hexachlorobenzene in excess of the MCL over many years could experience problems with their liver or kidneys, or adverse reproductive effects, and may have an increased risk of getting cancer.
Hexachlorocyclo-pentadiene (ppb)	.05	1000	50	50	Discharge from chemical factories	Some people who drink water containing hexachlorocyclopentadiene well in excess of the MCL over many years could experience problems with their kidneys or stomach.
Lindane (ppt)	.0002	1,000,000	200	200	Runoff/leaching from insecticide used on cattle, lumber, gardens	Some people who drink water containing lindane in excess of the MCL over many years could experience problems with their kidneys or liver.
Methoxychlor (ppb)	.04	1000	40	40	Runoff/leaching from insecticide used on fruits, vegetables, alfalfa, livestock	Some people who drink water containing methoxychlor in excess of the MCL over many years could experience reproductive difficulties.
Oxamyl [Vydate] (ppb)	.2	1000	200	200	Runoff/leaching from insecticide used on apples, potatoes and tomatoes	Some people who drink water containing oxamyl in excess of the MCL over many years could experience slight nervous system effects.
PCBs [Polychlorinated biphenyls] (ppt)	.0005	1,000,000	500	0	Runoff from landfills; Discharge of waste chemicals	Some people who drink water containing PCBs in excess of the MCL over many years could experience changes in their skin, problems with their thymus gland, immune deficiencies, or reproductive or nervous system difficulties, and may have an increased risk of getting cancer.
Pentachlorophenol (ppb)	.001	1000	1	0	Discharge from wood preserving factories	Some people who drink water containing pentachlorophenol in excess of the MCL over many years could experience problems with their liver or kidneys, and may have an increased risk of getting cancer.
Picloram (ppb)	.5	1000	500	500	Herbicide runoff	Some people who drink water containing picloram in excess of the MCL over many years could experience problems with their liver.
Simazine (ppb)	.004	1000	4	4	Herbicide runoff	Some people who drink water containing simazine in excess of the MCL over many years could experience problems with their blood.
Toxaphene (ppb)	.003	1000	3	0	Runoff/leaching from insecticide used on cotton and cattle	Some people who drink water containing toxaphene in excess of the MCL over many years could have problems with their kidneys, liver, or thyroid, and may have an increased risk of getting cancer.
Volatile Organic Contaminants
Benzene (ppb)	.005	1000	5	0	Discharge from factories; Leaching from gas storage tanks and landfills	Some people who drink water containing benzene in excess of the MCL over many years could experience anemia or a decrease in blood platelets, and may have an increased risk of getting cancer.
Bromate (ppb)	.010	1000	10	0	By-product of drinking water ((chlorination)) disinfection	Some people who drink water containing bromate in excess of the MCL over many years may have an increased risk of getting cancer.
Carbon tetrachloride (ppb)	.005	1000	5	0	Discharge from chemical plants and other industrial activities	Some people who drink water containing carbon tetrachloride in excess of the MCL over many years could experience problems with their liver and may have an increased risk of getting cancer.
Chloramines (ppm)	MRDL = 4	-	MRDL = 4	MRDLG = 4	Water additive used to control microbes	Some people who use drinking water containing chloramines well in excess of the MRDL could experience irritating effects to their eyes and nose. Some people who drink water containing chloramines well in excess of the MRDL could experience stomach discomfort or anemia.
Chlorine (ppm)	MRDL = 4	-	MRDL = 4	MRDLG = 4	Water additive used to control microbes	Some people who use drinking water containing chlorine well in excess of the MRDL could experience irritating effects to their eyes and nose. Some people who drink water containing chlorine well in excess of the MRDL could experience stomach discomfort.
Chlorite (ppm)	1	-	1	0.8	By-product of drinking water ((chlorination)) disinfection	Some infants and young children who drink water containing chlorite in excess of the MCL could experience nervous system effects. Similar effects may occur in fetuses of pregnant mothers who drink water containing chlorite in excess of the MCL. Some people may experience anemia.
Chlorine dioxide (ppb)	MRDL = .8	1000	MRDL = 800	MRDLG = 800	Water additive used to control microbes	Some infants and young children who drink water containing chlorine dioxide in excess of the MRDL could experience nervous system effects. Similar effects may occur in fetuses of pregnant mothers who drink water containing chlorine dioxide in excess of the MRDL. Some people may experience anemia.
Chlorobenzene (ppb)	.1	1000	100	100	Discharge from chemical and agricultural chemical factories	Some people who drink water containing chlorobenzene in excess of the MCL over many years could experience problems with their liver or kidneys.
o-Dichlorobenzene (ppb)	.6	1000	600	600	Discharge from industrial chemical factories	Some people who drink water containing o-dichlorobenzene well in excess of the MCL over many years could experience problems with their liver, kidneys, or circulatory systems.
p-Dichlorobenzene (ppb)	.075	1000	75	75	Discharge from industrial chemical factories	Some people who drink water containing p-dichlorobenzene in excess of the MCL over many years could experience anemia, damage to their liver, kidneys, or spleen, or changes in their blood.
1,2-Dichloroethane (ppb)	.005	1000	5	0	Discharge from industrial chemical factories	Some people who drink water containing 1,2-dichloroethane in excess of the MCL over many years may have an increased risk of getting cancer.
1,1-Dichloroethylene (ppb)	.007	1000	7	7	Discharge from industrial chemical factories	Some people who drink water containing 1,1-dichloroethylene in excess of the MCL over many years could experience problems with their liver.
cis-1,2-Dichloroethylene (ppb)	.07	1000	70	70	Discharge from industrial chemical factories	Some people who drink water containing cis-1,2-dichloroethylene in excess of the MCL over many years could experience problems with their liver.
trans-1,2-Dichloroethylene (ppb)	.1	1000	100	100	Discharge from industrial chemical factories	Some people who drink water containing trans-1,2-dichloroethylene well in excess of the MCL over many years could experience problems with their liver.
Dichloromethane (ppb)	.005	1000	5	0	Discharge from pharmaceutical and chemical factories	Some people who drink water containing dichloromethane in excess of the MCL over many years could have liver problems and may have an increased risk of getting cancer.
1,2-Dichloropropane (ppb)	.005	1000	5	0	Discharge from industrial chemical factories	Some people who drink water containing 1,2-dichloropropane in excess of the MCL over many years may have an increased risk of getting cancer.
Ethylbenzene (ppb)	.7	1000	700	700	Discharge from petroleum refineries	Some people who drink water containing ethylbenzene well in excess of the MCL over many years could experience problems with their liver or kidneys.
Haloacetic Acids (HAA) (ppb)	.060	1000	60	n/a	By-product of drinking water disinfection	Some people who drink water containing haloacetic acids in excess of the MCL over many years may have an increased risk of getting cancer.
Styrene (ppb)	.1	1000	100	100	Discharge from rubber and plastic factories; Leaching from landfills	Some people who drink water containing styrene well in excess of the MCL over many years could have problems with their liver, kidneys, or circulatory system.
Tetrachloroethylene (ppb)	.005	1000	5	0	Discharge from factories and dry cleaners	Some people who drink water containing tetrachloroethylene in excess of the MCL over many years could have problems with their liver, and may have an increased risk of getting cancer.
1,2,4-Trichlorobenzene (ppb)	.07	1000	70	70	Discharge from textile-finishing factories	Some people who drink water containing 1,2,4-trichlorobenzene well in excess of the MCL over many years could experience changes in their adrenal glands.
1,1,1-Trichloroethane (ppb)	.2	1000	200	200	Discharge from metal degreasing sites and other factories	Some people who drink water containing 1,1,1-trichloroethane in excess of the MCL over many years could experience problems with their liver, nervous system, or circulatory system.
1,1,2-Trichloroethane (ppb)	.005	1000	5	3	Discharge from industrial chemical factories	Some people who drink water containing 1,1,2-trichloroethane well in excess of the MCL over many years could have problems with their liver, kidneys, or immune systems.
Trichloroethylene (ppb)	.005	1000	5	0	Discharge from metal degreasing sites and other factories	Some people who drink water containing trichloroethylene in excess of the MCL over many years could experience problems with their liver and may have an increased risk of getting cancer.
TTHMs [Total trihalomethanes] (ppb)	0.10/.080	1000	100/80	n/a	By-product of drinking water ((chlorination)) disinfection	Some people who drink water containing trihalomethanes in excess of the MCL over many years may experience problems with their liver, kidneys, or central nervous systems, and may have an increased risk of getting cancer.
Toluene (ppm)	1	-	1	1	Discharge from petroleum factories	Some people who drink water containing toluene well in excess of the MCL over many years could have problems with their nervous system, kidneys, or liver.
Vinyl Chloride (ppb)	.002	1000	2	0	Leaching from PVC piping: Discharge from plastics factories	Some people who drink water containing vinyl chloride in excess of the MCL over many years may have an increased risk of getting cancer.
Xylenes (ppm)	10	-	10	10	Discharge from petroleum factories; Discharge from chemical factories	Some people who drink water containing xylenes in excess of the MCL over many years could experience damage to their nervous system.
Key
AL = Action Level
MCL = Maximum Contaminant Level
MCLG = Maximum Contaminant Level Goal
MFL = million fibers per liter
MRDL = Maximum Residual Disinfectant Level
MRDLG = Maximum Residual Disinfectant Level Goal
mrem/year = millirems per year (a measure of radiation absorbed by the body)
N/A = Not Applicable
NTU = Nephelometric Turbidity Units (a measure of water clarity)
pCi/1 = picocuries per liter (a measure of radioactivity)
ppm = parts per million, or milligrams per liter (mg/1)
ppb = parts per billion, or micrograms per liter ( g/1)
ppt = parts per trillion, or nanograms per liter
ppq = parts per quadrillion, or picograms per liter
TT = Treatment Technique

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-72012, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.20.050. 00-15-080, § 246-290-72012, filed 7/19/00, effective 8/19/00.]

     Reviser's note: The brackets and enclosed material in the text of the above section occurred in the copy filed by the agency and appear in the Register pursuant to the requirements of RCW 34.08.040.

OTS-6451.2

AMENDATORY SECTION(Amending WSR 03-08-037, filed 3/27/03, effective 4/27/03)

WAC 246-290-010   Definitions.   Abbreviations and acronyms:

     ADD - average day demand;

     AG - air gap;

     ANSI - American National Standards Institute;

     APWA - American Public Works Association;

     ASCE - American Society of Civil Engineers;

     AVB - atmospheric vacuum breaker;

     AWWA - American Water Works Association;

     BAT - best available technology;

     BAT - backflow assembly tester (for WAC 246-29-490);

     C - residual disinfectant concentration in mg/L;

     CCS - cross-connection control specialist;

     CFR - code of federal regulations;

     CPE - comprehensive performance evaluation;

     CT - the mathematical product in mg/L - minutes of "C" and "T";

     CTA - comprehensive technical assistance;

     CWSSA - critical water supply service area;

     DBPs - disinfection by-products;

     DCDA - double check detector assembly;

     DCVA - double check valve assembly;

     EPA - Environmental Protection Agency;

     ERU - equivalent residential unit;

     gph - gallons per hour;

     gpm - gallons per minute;

     GAC - granular activated carbon;

     GAC10 - granular activated carbon with ten-minute empty bed contact time based on average daily flow and one hundred eighty-day reactivation frequency;

     GWI - ground water under the direct influence of surface water;

     HAA5 - haloacetic acids (five);

     HPC - heterotrophic plate count;

     IAPMO - International Association of Plumbing and Mechanical Officials;

     kPa - kilo pascal (SI units of pressure);

     MCL - maximum contaminant level;

     MDD - maximum day demand;

     mg/L - milligrams per liter (1 mg/L = 1 ppm);

     mL - milliliter;

     mm - millimeter;

     MRDL - maximum residual disinfectant level;

     MRDLG - maximum residual disinfectant level goal;

     MTTP - maximum total trihalomethane potential;

     NSF - National Sanitation Foundation;

     NTNC - nontransient noncommunity;

     NTU - nephelometric turbidity unit;

     PAA - project approval application;

     pCi/L - picocuries per liter;

     PHD - peak hourly demand;

     ppm - parts per million (1 ppm = 1 mg/L);

     psi - pounds per square inch;

     PVBA - pressure vacuum breaker assembly;

     RPBA - reduced pressure backflow assembly;

     RPDA - reduced pressure detector assembly;

     SAL - state advisory level;

     SCA - sanitary control area;

     SDWA - Safe Drinking Water Act;

     SEPA - State Environmental Policy Act;

     SOC - synthetic organic chemical;

     SMA - satellite management agency;

     SPI - special purpose investigation;

     SRF - state revolving fund;

     SUVA - specific ultraviolet absorption;

     SVBA - spill resistant vacuum breaker assembly;

     SWTR - surface water treatment rule;

     T - disinfectant contact time in minutes;

     TTHM - total trihalomethane;

     TNC - transient noncommunity;

     TNTC - too numerous to count;

     TOC - total organic carbon;

     UBC - Uniform Building Code;

     ug/L - micrograms per liter;

     UL - Underwriters Laboratories, Inc.;

     umhos/cm - micromhos per centimeter;

     UPC - Uniform Plumbing Code;

     UTC - utilities and transportation commission;

     VOC - volatile organic chemical;

     WAC - Washington Administrative Code;

     WFI - water facilities inventory and report form; and

     WHPA - wellhead protection area.

     "Acute" means posing an immediate risk to human health.

     "Alternate filtration technology" means a filtration process for substantial removal of particulates (generally > 2 log Giardia lamblia cysts and((/or, for systems serving at least 10,000 people,)) ≥ 2-log removal of Cryptosporidium oocysts) by other than conventional, direct, diatomaceous earth, or slow sand filtration processes.

     "Analogous treatment system" means an existing water treatment system that has unit processes and source water quality characteristics that are similar to a proposed treatment system.

     "Approved air gap" means a physical separation between the free-flowing end of a potable water supply pipeline and the overflow rim of an open or nonpressurized receiving vessel. To be an air gap approved by the department, the separation must be at least:

     Twice the diameter of the supply piping measured vertically from the overflow rim of the receiving vessel, and in no case be less than one inch, when unaffected by vertical surfaces (sidewalls); and:

     Three times the diameter of the supply piping, if the horizontal distance between the supply pipe and a vertical surface (sidewall) is less than or equal to three times the diameter of the supply pipe, or if the horizontal distance between the supply pipe and intersecting vertical surfaces (sidewalls) is less than or equal to four times the diameter of the supply pipe and in no case less than one and one-half inches.

     "Approved atmospheric vacuum breaker" means an AVB of make, model, and size that is approved by the department. AVBs that appear on the current approved backflow prevention assemblies list developed by the University of Southern California Foundation for Cross-Connection Control and Hydraulic Research or that are listed or approved by other nationally recognized testing agencies (such as IAPMO, ANSI, or UL) acceptable to the local administrative authority are considered approved by the department.

     "Approved backflow preventer" means an approved air gap, an approved backflow prevention assembly, or an approved AVB. The terms "approved backflow preventer," "approved air gap," or "approved backflow prevention assembly" refer only to those approved backflow preventers relied upon by the purveyor for the protection of the public water system. The requirements of WAC 246-290-490 do not apply to backflow preventers installed for other purposes.

     "Approved backflow prevention assembly" means an RPBA, RPDA, DCVA, DCDA, PVBA, or SVBA of make, model, and size that is approved by the department. Assemblies that appear on the current approved backflow prevention assemblies list developed by the University of Southern California Foundation for Cross-Connection Control and Hydraulic Research or other entity acceptable to the department are considered approved by the department.

     "As-built drawing" means the drawing created by an engineer from the collection of the original design plans, including changes made to the design or to the system, that reflects the actual constructed condition of the water system.

     "Authorized agent" means any person who:

     Makes decisions regarding the operation and management of a public water system whether or not he or she is engaged in the physical operation of the system;

     Makes decisions whether to improve, expand, purchase, or sell the system; or

     Has discretion over the finances of the system.

     "Average day demand (ADD)" means the total quantity of water use from all sources of supply as measured or estimated over a calendar year divided by three hundred sixty-five. ADD is typically expressed as gallons per day per ERU (gpd/ERU).

     "Backflow" means the undesirable reversal of flow of water or other substances through a cross-connection into the public water system or consumer's potable water system.

     "Backflow assembly tester" means a person holding a valid BAT certificate issued in accordance with chapter 246-292 WAC.

     "Backpressure" means a pressure (caused by a pump, elevated tank or piping, boiler, or other means) on the consumer's side of the service connection that is greater than the pressure provided by the public water system and which may cause backflow.

     "Backsiphonage" means backflow due to a reduction in system pressure in the purveyor's distribution system and/or consumer's water system.

     "Best available technology (BAT)" means the best technology, treatment techniques, or other means that EPA finds, after examination for efficacy under field conditions, are available, taking cost into consideration.

     "Blended sample" means a sample collected from two or more individual sources at a point downstream of the confluence of the individual sources and prior to the first connection.

     "C" means the residual disinfectant concentration in mg/L at a point before or at the first consumer.

     "Category red operating permit" means an operating permit identified as such under chapter 246-294 WAC. Placement in this category results in permit issuance with conditions and a determination that the system is inadequate.

     "Chemical contaminant treatment facility" means a treatment facility specifically used for the purpose of removing chemical contaminants.

     "Clarification" means a treatment process that uses gravity (sedimentation) or dissolved air (flotation) to remove flocculated particles.

     "Closed system" means any water system or portion of a water system in which water is transferred to a higher pressure zone closed to the atmosphere, such as when no gravity storage is present.

     "Coagulant" means a chemical used in water treatment to destabilize particulates and accelerate the rate at which they aggregate into larger particles.

     "Coagulation" means a process using coagulant chemicals and rapid mixing to destabilize colloidal and suspended particles and agglomerate them into flocs.

     "Combination fire protection system" means a fire sprinkler system that:

     Is supplied only by the purveyor's water;

     Does not have a fire department pumper connection; and

     Is constructed of approved potable water piping and materials that serve both the fire sprinkler system and the consumer's potable water system.

     "Completely treated water" means water from a surface or GWI source that receives filtration or disinfection treatment that fully complies with the treatment technique requirements of Part 6 of this chapter as determined by the department.

     "Composite sample" means a sample in which more than one source is sampled individually by the water system and then composited by a certified laboratory by mixing equal parts of water from each source (up to five different sources) and then analyzed as a single sample.

     "Comprehensive monitoring plan" means a schedule that describes both the frequency and appropriate locations for sampling of drinking water contaminants as required by state and federal rules.

     "Comprehensive performance evaluation (CPE)" means a thorough review and analysis of a treatment plant's performance-based capabilities and 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 emphasizes approaches that can be implemented without significant capital improvements. The comprehensive performance evaluation must consist of at least 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.

     "Comprehensive technical assistance (CTA)" means technical assistance intended to identify specific steps that may help a water treatment plant overcome operational or design limitations identified during a comprehensive performance evaluation.

     "Confirmation" means to demonstrate the accuracy of results of a sample by analyzing another sample from the same location within a reasonable period of time, generally not to exceed two weeks. Confirmation is when analysis results fall within plus or minus thirty percent of the original sample results.

     "Confluent growth" means a continuous bacterial growth covering a portion or the entire filtration area of a membrane filter in which bacterial colonies are not discrete.

     "Conservation program" means policies and activities implemented to encourage or cause efficient use of water on a long-term basis. Conservation programs shall include identification of the conservation objectives of the purveyor, evaluation of conservation measures considered, and identification of specific conservation measures identified for implementation.

     "Construction completion report" means a form provided by the department and completed for each specific construction project to document:

     • Project construction in accordance with this chapter and general standards of engineering practice;

     • Physical capacity changes; and

     • Satisfactory test results.

     The completed form must be stamped with an engineer's seal, and signed and dated by a professional engineer.

     "Consumer" means any person receiving water from a public water system from either the meter, or the point where the service line connects with the distribution system if no meter is present. For purposes of cross-connection control, "consumer" means the owner or operator of a water system connected to a public water system through a service connection.

     "Consumer's water system," as used in WAC 246-290-490, means any potable and/or industrial water system that begins at the point of delivery from the public water system and is located on the consumer's premises. The consumer's water system includes all auxiliary sources of supply, storage, treatment, and distribution facilities, piping, plumbing, and fixtures under the control of the consumer.

     "Contaminant" means a substance present in drinking water that may adversely affect the health of the consumer or the aesthetic qualities of the water.

     "Contingency plan" means that portion of the wellhead protection program section of the water system plan or small water system management program that addresses the replacement of the major well(s) or wellfield in the event of loss due to ground water contamination.

     "Continuous monitoring" means determining water quality with automatic recording analyzers that operate without interruption twenty-four hours per day.

     "Conventional filtration treatment" means a series of processes including coagulation, flocculation, clarification, and filtration that together result in substantial particulate removal in compliance with Part 6 of this chapter.

     "Critical water supply service area (CWSSA)" means a geographical area which is characterized by a proliferation of small, inadequate water systems, or by water supply problems which threaten the present or future water quality or reliability of service in such a manner that efficient and orderly development may best be achieved through coordinated planning by the water utilities in the area.

     "Cross-connection" means any actual or potential physical connection between a public water system or the consumer's water system and any source of nonpotable liquid, solid, or gas that could contaminate the potable water supply by backflow.

     "Cross-connection control program" means the administrative and technical procedures the purveyor implements to protect the public water system from contamination via cross-connections as required in WAC 246-290-490.

     "Cross-connection control specialist" means a person holding a valid CCS certificate issued in accordance with chapter 246-292 WAC.

     "Cross-connection control summary report" means the annual report that describes the status of the purveyor's cross-connection control program.

     "CT" or "CTcalc" means the product of "residual disinfectant concentration" (C) and the corresponding "disinfectant contact time" (T) i.e., "C" x "T."

     "CT_99.9" means the CT value required for 99.9 percent (3 log) inactivation of Giardia lamblia cysts.

     "CTreq" means the CT value a system shall provide to achieve a specific percent inactivation of Giardia lamblia cysts or other pathogenic organisms of health concern as directed by the department.

     "Curtailment" means short-term, infrequent actions by a purveyor and its consumers to reduce their water use during or in anticipation of a water shortage.

     "Dead storage" means the volume of stored water not available to all consumers at the minimum design pressure in accordance with WAC 246-290-230 (5) and (6).

     "Demand forecast" means an estimate of future water system water supply needs assuming historically normal weather conditions and calculated using numerous parameters, including population, historic water use, local land use plans, water rates and their impacts on consumption, employment, projected conservation savings from implementation of a conservation program, and other appropriate factors.

     "Department" means the Washington state department of health or health officer as identified in a joint plan of operation in accordance with WAC 246-290-030(1).

     "Design and construction standards" means department design guidance and other peer reviewed documents generally accepted by the engineering profession as containing fundamental criteria for design and construction of water facility projects. Design and construction standards are comprised of performance and sizing criteria and reference general construction materials and methods.

     "Diatomaceous earth filtration" means a filtration process for substantial removal of particulates (> 2 log Giardia lamblia cysts) in which:

     A precoat cake of graded diatomaceous earth filter media is deposited on a support membrane (septum); and

     Water is passed through the cake on the septum while additional filter media, known as body feed, is continuously added to the feed water to maintain the permeability of the filter cake.

     "Direct filtration" means a series of processes including coagulation, flocculation, and filtration (but excluding sedimentation) that together result in substantial particulate removal in compliance with Part 6 of this chapter.

     "Direct service connection" means a service hookup to a property that is contiguous to a water distribution main and where additional distribution mains or extensions are not needed to provide service.

     "Disinfectant contact time (T in CT)" means: When measuring the first or only C, the time in minutes it takes water to move from the point of disinfectant application to a point where the C is measured; and

     For subsequent measurements of C, the time in minutes it takes water to move from one C measurement point to the C measurement point for which the particular T is being calculated.

     "Disinfection" means the use of chlorine or other agent or process the department approves for killing or inactivating microbiological organisms, including pathogenic and indicator organisms.

     "Disinfection profile" means a summary of Giardia lamblia inactivation through a surface water treatment plant.

     "Distribution coliform sample" means a sample of water collected from a representative location in the distribution system at or after the first service and analyzed for coliform presence in compliance with this chapter.

     "Distribution-related projects" means distribution projects such as storage tanks, booster pump facilities, transmission mains, pipe linings, and tank coating. It does not mean source of supply (including interties) or water quality treatment projects.

     "Distribution reservoir" means a water storage structure that is integrated with a water system's distribution network to provide for variable system demands including, but not limited to, daily equalizing storage, standby storage, or fire reserves, or to provide for disinfectant contact time.

     "Distribution system" means all piping components of a public water system that serve to convey water from transmission mains linked to source, storage and treatment facilities to the consumer excluding individual services.

     "Domestic or other nondistribution system plumbing problem," means contamination of a system having more than one service connection with the contamination limited to the specific service connection from which the sample was taken.

     "Drinking water state revolving fund (DWSRF)" means the revolving loan program financed by the state and federal governments and managed by the state for the purpose of assisting water systems to meet their capital needs associated with complying with the federal Safe Drinking Water Act.

     "Duplicate (verification) sample" means a second sample collected at the same time and location as the first sample and used for verification.

     "Emergency" means an unforeseen event that causes damage or disrupts normal operations and requires immediate action to protect public health and safety.

     "Emergency source" means any source that is approved by the department for emergency purposes only, is not used for routine or seasonal water demands, is physically disconnected, and is identified in the purveyor's emergency response plan.

     "Engineering design review report" means a form provided by the department and completed for a specific distribution-related project to document:

     • Engineering review of a project report and/or construction documents under the submittal exception process in accordance with WAC 246-290-125(3); and

     • Design in accordance with this chapter and general standards of engineering practice.

     The completed form must be stamped with engineer's seal, and signed and dated by a professional engineer.

     "Equalizing storage" means the volume of storage needed to supplement supply to consumers when the peak hourly demand exceeds the total source pumping capacity.

     "Equivalent residential unit (ERU)" means a system-specific unit of measure used to express the amount of water consumed by a typical full-time single family residence.

     "Expanding public water system" means a public water system installing additions, extensions, changes, or alterations to their existing source, transmission, storage, or distribution facilities that will enable the system to increase in size its existing service area and/or its number of approved service connections. Exceptions:

     A system that connects new approved individual retail or direct service connections onto an existing distribution system within an existing service area; or

     A distribution system extension in an existing service area identified in a current and approved water system plan or project report.

     "Filter profile" means a graphical representation of individual filter performance in a direct or conventional surface water filtration plant, based on continuous turbidity measurements or total particle counts versus time for an entire filter run, from startup to backwash inclusively, that includes an assessment of filter performance while another filter is being backwashed.

     "Filtration" means a process for removal of particulate matter from water by passage through porous media.

     "Financial viability" means the capability of a water system to obtain sufficient funds to construct, operate, maintain, and manage a public water system, on a continuing basis, in full compliance with federal, state, and local requirements.

     "Fire flow" means the maximum rate and duration of water flow needed to suppress a fire under WAC 246-293-640 or as required under local fire protection authority standards.

     "Fire suppression storage" means the volume of stored water available during fire suppression activities to satisfy minimum pressure requirements per WAC 246-290-230.

     "First consumer" means the first service connection associated with any source (i.e., the point where water is first withdrawn for human consumption, excluding connections where water is delivered to another water system covered by these regulations).

     "Flocculation" means a process enhancing agglomeration and collection of colloidal and suspended particles into larger, more easily settleable or filterable particles by gentle stirring.

     "Flow-through fire protection system" means a fire sprinkler system that:

     Is supplied only by the purveyor's water;

     Does not have a fire department pumper connection;

     Is constructed of approved potable water piping and materials to which sprinkler heads are attached; and

     Terminates at a connection to a toilet or other plumbing fixture to prevent the water from becoming stagnant.

     "Grab sample" means a water quality sample collected at a specific instant in time and analyzed as an individual sample.

     "Ground water under the direct influence of surface water (GWI)" means any water beneath the surface of the ground that the department determines has the following characteristics:

     Significant occurrence of insects or other macroorganisms, algae, or large-diameter pathogens such as Giardia lamblia or ((for systems serving ten thousand people or more)), Cryptosporidium; or

     Significant and relatively rapid shifts in water characteristics such as turbidity, temperature, conductivity, or pH closely correlating to climatological or surface water conditions where natural conditions cannot prevent the introduction of surface water pathogens into the source at the system's point of withdrawal.

     "Guideline" means a department document assisting the purveyor in meeting a rule requirement.

     "Health officer" means the health officer of the city, county, city-county health department or district, or an authorized representative.

     "Heterotrophic Plate Count (HPC)" means a procedure to measure a class of bacteria that use organic nutrients for growth. The density of these bacteria in drinking water is measured as colony forming units per milliliter and is referred to as the HPC.

     "High health cross-connection hazard" means a cross-connection which could impair the quality of potable water and create an actual public health hazard through poisoning or spread of disease by sewage, industrial liquids or waste.

     "Human consumption" means the use of water for drinking, bathing or showering, hand washing, food preparation, cooking, or oral hygiene.

     "Hydraulic analysis" means the study of a water system's distribution main and storage network to determine present or future adequacy for provision of service to consumers within the established design parameters for the system under peak flow conditions, including fire flow. The analysis is used to establish any need for improvements to existing systems or to substantiate adequacy of design for distribution system components such as piping, elevated storage, booster stations or similar facilities used to pump and convey water to consumers.

     "Inactivation" means a process which renders pathogenic microorganisms incapable of producing disease.

     "Inactivation ratio" means the ratio obtained by dividing CTcalc by CTreq.

     "Incompletely treated water" means water from a surface or GWI source that receives filtration and/or disinfection treatment that does not fully comply with the treatment technique requirements of Part 6 of this chapter as determined by the department.

     "In-line filtration" means a series of processes, including coagulation and filtration (but excluding flocculation and sedimentation) that together result in particulate removal.

     "In-premises protection" means a method of protecting the health of consumers served by the consumer's potable water system, located within the property lines of the consumer's premises by the installation of an approved air gap or backflow prevention assembly at the point of hazard, which is generally a plumbing fixture.

     "Intertie" means an interconnection between public water systems permitting the exchange or delivery of water between those systems.

     "Legionella" means a genus of bacteria containing species which cause a type of pneumonia called Legionnaires' Disease.

     "Limited alternative to filtration" means a process that ensures greater removal and/or inactivation efficiencies of pathogenic organisms than would be achieved by the combination of filtration and chlorine disinfection.

     "Local administrative authority" means the local official, board, department, or agency authorized to administer and enforce the provisions of the Uniform Plumbing Code as adopted under chapter 19.27 RCW.

     "Low health cross-connection hazard" means a cross-connection that could cause an impairment of the quality of potable water to a degree that does not create a hazard to the public health, but does adversely and unreasonably affect the aesthetic qualities of such potable waters for domestic use.

     "Major project" means all construction projects subject to SEPA in accordance with WAC 246-03-030 (3)(a) and include all surface water source development, all water system storage facilities greater than one-half million gallons, new transmission lines longer than one thousand feet and larger than eight inches in diameter located in new rights of way and major extensions to existing water distribution systems involving use of pipes greater than eight inches in diameter, that are designed to increase the existing service area by more than one square mile.

     "Mandatory curtailment" means curtailment required by a public water system of specified water uses and consumer classes for a specified period of time.

     "Maximum contaminant level (MCL)" means the maximum permissible level of a contaminant in water the purveyor delivers to any public water system user, measured at the locations identified under WAC 246-290-300, Table 3.

     "Maximum contaminant level violation" means a confirmed measurement above the MCL and for a duration of time, where applicable, as outlined under WAC 246-290-310.

     "Maximum day demand (MDD)" means the highest actual or estimated quantity of water that is, or is expected to be, used over a twenty-four hour period, excluding unusual events or emergencies. MDD is typically expressed as gallons per day per ERU (gpd/ERU).

     "Monitoring waiver" means an action taken by the department under WAC 246-290-300 (4)(g) or (7)(f) to allow a water system to reduce specific monitoring requirements based on a determination of low source vulnerability to contamination.

     "Nested storage" means one component of storage is contained within the component of another.

     "Nonacute" means posing a possible or less than immediate risk to human health.

     "Nonresident" means a person having access to drinking water from a public water system, but who lives elsewhere. Examples include travelers, transients, employees, students, etc.

     "Normal operating conditions" means those conditions associated with the designed, day-to-day provision of potable drinking water that meets regulatory water quality standards and the routine service expectations of the system's consumers at all times, including meeting fire flow demands. Operation under conditions such as power outages, floods, or unscheduled transmission or distribution disruptions, even if considered in the system design, are considered abnormal.

     "Operational storage" means the volume of distribution storage associated with source or booster pump normal cycling times under normal operating conditions and is additive to the equalizing and standby storage components, and to fire flow storage if this storage component exists for any given tank.

     "Peak hourly demand (PHD)" means the maximum rate of water use, excluding fire flow, that can be expected to occur within a defined service area over a continuous sixty minute time period. PHD is typically expressed in gallons per minute (gpm).

     "Peak hourly flow" means, for the purpose of CT calculations, the greatest volume of water passing through the system during any one hour in a day.

     "Performance criteria" means the level at which a system shall operate in order to maintain system reliability compliance, in accordance with WAC 246-290-420, and to meet consumers' reasonable expectations.

     "Permanent residence" means any dwelling that is, or could reasonably be expected to be, occupied on a continuous basis.

     "Permanent source" means a public water system supply source that is used regularly each year, and based on expected operational requirements of the system, will be used more than three consecutive months in any twelve-month period. For seasonal water systems that are in operation for less than three consecutive months per year, their sources shall also be considered to be permanent.

     "Point of disinfectant application" means the point where the disinfectant is added, and where water downstream of that point is not subject to contamination by untreated surface water.

     "Population served" means the number of persons, resident and nonresident, having immediate access to drinking water from a public water system, whether or not such persons have actually consumed water from that system. The number of nonresidents shall be the average number of persons having immediate access to drinking water on days access was provided during that month. In the absence of specific population data, the number of residents shall be computed by multiplying the number of active services by two and one-half.

     "Potable" means water suitable for drinking by the public.

     "Potential GWI" means a source identified by the department as possibly under the influence of surface water, and includes, but is not limited to, all wells with a screened interval fifty feet or less from the ground surface at the wellhead and located within two hundred feet of a surface water, and all Ranney wells, infiltration galleries, and springs.

     "Premises isolation" means a method of protecting a public water system by installation of approved air gaps or approved backflow prevention assemblies at or near the service connection or alternative location acceptable to the purveyor to isolate the consumer's water system from the purveyor's distribution system.

     "Pressure filter" means an enclosed vessel containing properly sized and graded granular media through which water is forced under greater than atmospheric pressure.

     "Primary disinfection" means a treatment process for achieving inactivation of Giardia lamblia cysts, viruses, or other pathogenic organisms of public health concern to comply with the treatment technique requirements of Part 6 of this chapter.

     "Primary standards" means standards based on chronic, nonacute, or acute human health effects.

     "Primary turbidity standard" means an accurately prepared formazin solution or commercially prepared polymer solution of known turbidity (prepared in accordance with "standard methods") that is used to calibrate bench model and continuous turbidimeters (instruments used to measure turbidity).

     "Project approval application (PAA)" means a department form documenting ownership of water system, design engineer for the project, and type of project.

     "Protected ground water source" means a ground water source the purveyor shows to the department's satisfaction as protected from potential sources of contamination on the basis of hydrogeologic data and/or satisfactory water quality history.

     "Public water system" is defined and referenced under WAC 246-290-020.

     "Purchased source" means water a purveyor purchases from a public water system not under the control of the purveyor for distribution to the purveyor's consumers.

     "Purveyor" means an agency, subdivision of the state, municipal corporation, firm, company, mutual or cooperative association, institution, partnership, or person or other entity owning or operating a public water system. Purveyor also means the authorized agents of such entities.

     "Reclaimed water" means effluent derived in any part from sewage from a wastewater treatment system that has been adequately and reliably treated, so that as a result of that treatment, it is suitable for beneficial use or a controlled use that would not otherwise occur, and it is no longer considered wastewater.

     "Record drawings" means the drawings bearing the seal and signature of a professional engineer that reflect the modifications made to construction documents, documenting actual constructed conditions of the water system facilities.

     "Recreational tract" means an area that is clearly defined for each occupant, but has no permanent structures with internal plumbing, and the area has been declared as such in the covenants or on the recorded plat in order to be eligible for reduced design considerations.

     "Regional public water supplier" means a water system that provides drinking water to one, or more, other public water systems.

     "Regularly" means four hours or more per day for four days or more per week.

     "Removal credit" means the level (expressed as a percent or log) of Giardia and virus removal the department grants a system's filtration process.

     "Repeat sample" means a sample collected to confirm the results of a previous analysis.

     "Resident" means an individual living in a dwelling unit served by a public water system.

     "Residual disinfectant concentration" means the analytical level of a disinfectant, measured in milligrams per liter, that remains in water following the application (dosing) of the disinfectant after some period of contact time.

     "Same farm" means a parcel of land or series of parcels that are connected by covenants and devoted to the production of livestock or agricultural commodities for commercial purposes and does not qualify as a Group A public water system.

     "Sanitary survey" means a review, inspection, and assessment of a public water system by the department or department designee including, but not limited to: Source, facilities, equipment, administration and operation, maintenance procedures, monitoring, recordkeeping, planning documents and schedules, and management practices. The purpose of the survey is to evaluate the adequacy of the water system for producing and distributing safe and adequate drinking water.

     "Satellite management agency (SMA)" means a person or entity that is approved by the department to own or operate public water systems on a regional or county-wide basis without the necessity for a physical connection between such systems.

     "Seasonal source" means a public water system source used on a regular basis, that is not a permanent or emergency source.

     "Secondary standards" means standards based on factors other than health effects.

     "Service connection" means a connection to a public water system designed to provide potable water to a single family residence, or other residential or nonresidential population. When the connection provides water to a residential population without clearly defined single family residences, the following formulas shall be used in determining the number of services to be included as residential connections on the WFI form:

     Divide the average population served each day by two and one-half; or

     Using actual water use data, calculate the total ERUs represented by the service connection in accordance with department design guidance.

     In no case shall the calculated number of services be less than one.

     "Significant noncomplier" means a system that is violating or has violated department rules, and the violations may create, or have created an imminent or a significant risk to human health. Such violations include, but are not limited to, repeated violations of monitoring requirements, failure to address an exceedance of permissible levels of regulated contaminants, or failure to comply with treatment technique standards or requirements.

     "Simple disinfection" means any form of disinfection that requires minimal operational control in order to maintain the disinfection at proper functional levels, and that does not pose safety concerns that would require special care, equipment, or expertise. Examples include hypochlorination, UV-light, contactor chlorination, or any other form of disinfection practice that is safe to use and easy to routinely operate and maintain.

     "Slow sand filtration" means a process involving passage of source water through a bed of sand at low velocity (generally less than 0.10 gpm/ft²) that results in substantial particulate removal (> 2 log Giardia lamblia cysts) by physical and biological mechanisms.

     "Source meter" means a meter that measures total output of a water source over specific time periods.

     "Source water" means untreated water that is not subject to recontamination by surface runoff and:

     For unfiltered systems, enters the system immediately before the first point of disinfectant application; and

     For filtered systems, enters immediately before the first treatment unit of a water treatment facility.

     "Special purpose investigation (SPI)" means on-site inspection of a public water system by the department or designee to address a potential public health concern, regulatory violation, or consumer complaint.

     "Special purpose sample" means a sample collected for reasons other than the monitoring compliance specified in this chapter.

     "Spring" means a source of water where an aquifer comes in contact with the ground surface.

     "Standard methods" means the 18th edition of the book, titled Standard Methods for the Examination of Water and Waste Water, jointly published by the American Public Health Association, American Water Works Association (AWWA), and Water Pollution Control Federation. This book is available through public libraries or may be ordered from AWWA, 6666 West Quincy Avenue, Denver, Colorado 80235.

     "Standby storage" means the volume of stored water available for use during a loss of source capacity, power, or similar short-term emergency.

     "State advisory level (SAL)" means a level established by the department and state board of health for a contaminant without an existing MCL. The SAL represents a level that when exceeded, indicates the need for further assessment to determine if the chemical is an actual or potential threat to human health.

     "State board of health" and "board" means the board created by RCW 43.20.030.

     "Subpart H System" see definition for "surface water system."

     "Surface water" means a body of water open to the atmosphere and subject to surface runoff.

     "Surface water system" means a public water system that uses in whole, or in part, source water from a surface supply, or ground water under the direct influence of surface water (GWI) supply. This includes systems that operate surface water treatment facilities, and systems that purchase "completely treated water" (as defined in this subsection). A "surface water system" is also referred to as a "Subpart H System" in some federal regulatory language adopted by reference and the two terms are considered equivalent for the purposes of this chapter.

     "Susceptibility assessment" means the completed Susceptibility Assessment Survey Form developed by the department to evaluate the hydrologic setting of the water source and assess its contribution to the source's overall susceptibility to contamination from surface activities.

     "Synthetic organic chemical (SOC)" means a manufactured carbon-based chemical.

     "System capacity" means the system's operational, technical, managerial, and financial capability to achieve and maintain compliance with all relevant local, state, and federal plans and regulations.

     "System physical capacity" means the maximum number of service connections or equivalent residential units (ERUs) that the system can serve when considering the limitation of each system component such as source, treatment, storage, transmission, or distribution, individually and in combination with each other.

     "Time-of-travel" means the time required for ground water to move through the water bearing zone from a specific point to a well.

     "Too numerous to count (TNTC)" means the total number of bacterial colonies exceeds 200 on a 47-mm diameter membrane filter used for coliform detection.

     "Tracer study" means a field study conducted to determine the disinfectant contact time, T, provided by a water system component, such as a clearwell or storage reservoir, used for Giardia lamblia cyst and virus inactivation. The study involves introducing a tracer chemical at the inlet of the contact basin and measuring the resulting outlet tracer concentration as a function of time.

     "Transmission line" means pipes used to convey water from source, storage, or treatment facilities to points of distribution or distribution mains, and from source facilities to treatment or storage facilities. This also can include transmission mains connecting one section of distribution system to another section of distribution system as long as this transmission main is clearly defined as such on the plans and no service connections are allowed along the transmission main.

     "Treatment technique requirement" means a department-established requirement for a public water system to provide treatment, such as filtration or disinfection, as defined by specific design, operating, and monitoring requirements. A "treatment technique requirement" is established in lieu of a primary MCL when monitoring for the contaminant is not economically or technologically feasible.

     "Trihalomethane (THM)" means one of a family of organic compounds, named as derivatives of methane, where three of the four hydrogen atoms in methane are each substituted by a halogen atom in the molecular structure. THMs may occur when chlorine, a halogen, is added to water containing organic material and are generally found in water samples as disinfection by-products.

     "Turbidity event" means a single day or series of consecutive days, not to exceed fourteen, when one or more turbidity measurement each day exceeds 5 NTU.

     "T10" means the time it takes ten percent of the water passing through a system contact tank intended for use in the inactivation of Giardia lamblia cysts, viruses, and other microorganisms of public health concern, as determined from a tracer study conducted at peak hourly flow or from published engineering reports or guidance documents for similarly configured tanks.

     "Unapproved auxiliary water supply" means a water supply (other than the purveyor's water supply) on or available to the consumer's premises that is either not approved for human consumption by the health agency having jurisdiction or is not otherwise acceptable to the purveyor.

     "Uncovered distribution reservoir" means a distribution reservoir that is open, without a suitable water-tight roof or cover, where the potable water supply is exposed to external contaminants, including but not limited to people, birds, animals, and insects and will undergo no further treatment except for residual disinfection.

     "Uniform Plumbing Code" means the code adopted under RCW 19.27.031(4) and amended under chapter 51-46 WAC. This code establishes statewide minimum plumbing standards applicable within the property lines of the consumer's premises.

     "Used water" means water which has left the control of the purveyor.

     "Verification" means to demonstrate the results of a sample to be precise by analyzing a duplicate sample. Verification occurs when analysis results fall within plus or minus thirty percent of the original sample.

     "Virus" means a virus of fecal origin which is infectious to humans and transmitted through water.

     "Volatile organic chemical (VOC)" means a manufactured carbon-based chemical that vaporizes quickly at standard pressure and temperature.

     "Voluntary curtailment" means a curtailment of water use requested, but not required of consumers.

     "Waterborne disease outbreak" means the significant occurrence of acute infectious illness, epidemiologically associated with drinking water from a public water system, as determined by the appropriate local health agency or the department.

     "Water facilities inventory (WFI) form" means the department form summarizing each public water system's characteristics.

     "Water right" means a permit, claim, or other authorization, on record with or accepted by the department of ecology, authorizing the beneficial use of water in accordance with all applicable state laws.

     "Water right assessment" means an evaluation of the legal ability of a water system to use water for existing or proposed usages in conformance with state water right laws. Such an assessment may be done by a water system, a purveyor, the department of ecology, or any combination thereof.

     "Watershed" means the region or area that:

     Ultimately drains into a surface water source diverted for drinking water supply; and

     Affects the physical, chemical, microbiological, and radiological quality of the source.

     "Water shortage" means a situation during which the water supplies of a system cannot meet normal water demands for the system, including peak periods.

     "Water shortage response plan" means a plan outlining policies and activities to be implemented to reduce water use on a short-term basis during or in anticipation of a water shortage.

     "Well field" means a group of wells one purveyor owns or controls that:

     Draw from the same aquifer or aquifers as determined by comparable inorganic chemical analysis and comparable static water level and top of the open interval elevations; and

     Discharge water through a common pipe and the common pipe shall allow for collection of a single sample before the first distribution system connection.

     "Wellhead protection area (WHPA)" means the portion of a well's, wellfield's or spring's zone of contribution defined as such using WHPA criteria established by the department.

     "Zone of contribution" means the area surrounding a pumping well or spring that encompasses all areas or features that supply ground water recharge to the well or spring.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-010, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-010, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-010, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-010, filed 3/25/93, effective 4/25/93; 92-04-070 (Order 241B), § 246-290-010, filed 2/4/92, effective 3/6/92. Statutory Authority: Chapter 43.20 RCW. 91-07-031 (Order 150B), § 246-290-010, filed 3/15/91, effective 4/15/91. Statutory Authority: RCW 43.20.050. 91-02-051 (Order 124B), recodified as § 246-290-010, filed 12/27/90, effective 1/31/91. Statutory Authority: P.L. 99-339. 89-21-020 (Order 336), § 248-54-015, filed 10/10/89, effective 11/10/89. Statutory Authority: RCW 34.04.045. 88-05-057 (Order 307), § 248-54-015, filed 2/17/88. Statutory Authority: RCW 43.20.050. 83-19-002 (Order 266), § 248-54-015, filed 9/8/83.]

     141.2 Definitions. Only those definitions listed as follows:

Action level;
Corrosion inhibitor;
Effective corrosion inhibitor residual;
Enhanced coagulation;
Enhanced softening;
Granular activated carbon (GAC10);
Haloacetic acids (five) (HAA5);
First draw sample;
Large water system;
Lead service line;
Maximum residual disinfectant level (MRDL);
Maximum residual disinfectant level goal (MRDLG);
Medium-size water system;
Optimal corrosion control treatment;
Service line sample;
Single family structure;
Small water system;
Specific ultraviolet absorption (SUVA); and
Total Organic Carbon (TOC).
141.12	Maximum contaminant levels for organic chemicals.
141.13	Maximum contaminant levels for turbidity.
141.21	Coliform monitoring.
141.22	Turbidity sampling and analytical requirements.
141.23(a) -excluding (i)(2)	141.23(j), Inorganic chemical sampling.
141.23(m) -	141.23(o)
141.24(a) -	141.24(d), Organic chemicals other than total trihalomethanes.
141.24 (f)(1) - 141.24 (f)(15),
141.24 (f)(18), 141.24 (f)(19),
141.24 (f)(21), 141.24 (f)(22)
141.24 (g)(1) - 141.24 (g)(9),
141.24 (g)(12) - 141.24 (g)(14),
141.24 (h)(1) - 141.24 (h)(11),
141.24 (h)(14) - 141.24 (h)(17)
141.24 (h)(20)
141.25(a),	141.25 (c) - (d), Analytical methods for radioactivity.
141.26	Monitoring frequency and compliance for radioactivity in community water systems.
141.31(d)	Reporting of public notices and compliance certifications.
141.33(e)	Record maintenance of public notices and certifications.
141.40(a) -	141.40(e), Special monitoring for inorganic and organic chemicals.
141.40(g), 141.40(i) - 141.40(n)
141.61	Maximum contaminant levels for organic contaminants.
141.62, excluding (b)	Maximum contaminant levels for inorganic chemical and physical contaminants.
141.64(c)	Best Available Technologies (BATs) for Disinfection By-Products.
141.65(c)	Best Available Technologies (BATs) for Maximum Residual Disinfectant Levels.
141.66	Maximum contaminant levels for radionuclides.
Control of Lead and Copper
141.80	General requirements.
141.81	Applicability of corrosion control treatment steps to small, medium-size and large water systems.
141.82(a) -	141.82(h) Description of corrosion control treatment requirements.
141.83	Source water treatment requirements.
141.84	Lead service line replacement requirements.
141.85	Public education and supplemental monitoring requirements.
141.86 (a) - (f)	Monitoring requirements for lead and copper in tap water.
141.87	Monitoring requirements for water quality parameters.
141.88	Monitoring requirements for lead and copper in source water.
141.89	Analytical methods for lead and copper testing.
141.90, excluding (a)(4)	Reporting requirements.
141.91	Recordkeeping requirements.
Disinfectants and Disinfection By-Products (D/DBP)
141.130	General requirements.
141.131	Analytical requirements.
141.132	Monitoring requirements.
141.133	Compliance.
141.134	Reporting and recordkeeping.
141.135	Treatment technique for control of disinfection by-product precursors.
Enhanced Filtration - Reporting and Recordkeeping
141.175(b)	Individual filter reporting and follow-up action requirements for systems treating surface water with conventional, direct, or in-line filtration and serving at least 10,000 people.
141.201, excluding (3)(ii) of Table 1	General public notification requirements.
141.202, excluding (3) of Table 1	Tier 1 Public Notice - Form, manner, and frequency of notice.
141.203	Tier 2 Public Notice - Form, manner, and frequency of notice.
141.204	Tier 3 Public Notice - Form, manner, and frequency of notice.
141.205	Content of the public notice.
141.206	Notice to new billing units or new customers.
141.207	Special notice of the availability of unregulated contaminant monitoring results.
141.208	Special notice for exceedances of the SMCL for fluoride.
Subpart Q - Public Notification Rule, Appendix A and B
Subpart T - Enhanced Filtration and Disinfection - Systems Serving Fewer Than 10,000 People
141.530 - 141.544	Disinfection profile and benchmark.
141.563	Follow-up actions required.
141.570, excluding (c)	Reporting requirements.
143.1 - 143.4	Secondary contaminants.

     Copies of the incorporated sections and subsections of Title 40 CFR are available from the Department of Health, Airdustrial Center Building 3, P.O. Box 47822, Olympia, Washington 98504-7822, or by calling the department's drinking water hotline at 1-800-521-0323.

[Statutory Authority: RCW 43.20.050 (2) and (3) and RCW 70.119A.080. 03-08-037, § 246-290-025, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-025, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-025, filed 6/22/94, effective 7/23/94.]

     (a) Bacteriological and turbidity analysis results shall be kept for five years. Chemical analysis results shall be kept for as long as the system is in operation. Records of daily source meter readings shall be kept for ten years. Other records of operation and analyses required by the department shall be kept for three years. All records shall bear the signature of the operator in responsible charge of the water system or his or her representative. Systems shall keep these records available for inspection by the department and shall send the records to the department if requested. Actual laboratory reports may be kept or data may be transferred to tabular summaries, provided the following information is included:

     (i) The date, place, and time of sampling, and the name of the person collecting the sample;

     (ii) Identification of the sample type (routine distribution system sample, repeat sample, source or finished water sample, or other special purpose sample);

     (iii) Date of analysis;

     (iv) Laboratory and person responsible for performing analysis;

     (v) The analytical method used; and

     (vi) The results of the analysis.

     (b) Records of action taken by the system to correct violations of primary drinking water standards. For each violation, records of actions taken to correct the violation, and copies of public notifications shall be kept for no less than three years after the last corrective action taken.

     (c) Copies of any written reports, summaries, or communications relating to sanitary surveys or SPIs of the system conducted by system personnel, by a consultant or by any local, state, or federal agency, shall be kept for ten years after completion of the sanitary survey or SPI involved.

     (d) Copies of project reports, construction documents and related drawings, inspection reports and approvals shall be kept for the life of the facility.

     (e) Where applicable, daily records of the following shall be kept for a minimum of three years:

     (i) Chlorine residual;

     (ii) Fluoride level;

     (iii) Water treatment plant performance including, but not limited to:

     (A) Type of chemicals used and quantity;

     (B) Amount of water treated; and

     (C) Results of analyses.

     (iv) Turbidity;

     (v) Source meter readings; and

     (vi) Other information as specified by the department.

     (f) The purveyor shall retain copies of public notices made in accordance with Part 7, Subpart A of this chapter and certifications made to the department under 40 CFR 141.33(e) for a period of at least three years after issuance.

     (g) Purveyors using conventional, direct, or in-line filtration that recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes within their treatment plant shall, beginning no later than June 8, 2004, collect and retain on file the following information for review and evaluation by the department:

     (i) A copy of the recycle notification and information submitted to the department in accordance with WAC 246-290-660 (4)(a)(i).

     (ii) A list of all recycle flows and the frequency with which they are returned.

     (iii) Average and maximum backwash flow rate through the filters and the average and maximum duration of the filter backwash process in minutes.

     (iv) Typical filter run length and a written summary of how filter run length is determined.

     (v) The type of treatment provided for the recycle flow.

     (vi) Data on the physical dimensions of the equalization and/or treatment units, typical and maximum hydraulic loading rates, type of treatment chemicals used and average dose and frequency of use, and frequency at which solids are removed, if applicable.

     (h) Purveyors required to conduct disinfection profiling and benchmarking in accordance with 40 CFR 141.530 through 141.544 shall retain the results on file indefinitely.

     (2) Reporting.

     (a) Unless otherwise specified in this chapter, the purveyor shall report to the department within forty-eight hours the failure to comply with any national primary drinking water regulation (including failure to comply with any monitoring requirements) as set forth in this chapter. For violations assigned to Tier 1 in WAC 246-290-71001, the department must be notified as soon as possible, but no later than twenty-four hours after the violation is known.

     (b) The purveyor shall submit to the department reports required by this chapter, including tests, measurements, and analytic reports. Monthly reports are due before the tenth day of the following month, unless otherwise specified in this chapter.

     (c) The purveyor shall submit to the department copies of any written summaries or communications relating to the status of monitoring waivers during each monitoring cycle or as directed by the department.

     (d) Source meter readings shall be made available to the department.

     (e) Water facilities inventory form (WFI).

     (i) Purveyors of community and NTNC systems shall submit an annual WFI update to the department;

     (ii) Purveyors of TNC systems shall submit an updated WFI to the department as requested;

     (iii) Purveyors shall submit an updated WFI to the department within thirty days of any change in name, category, ownership, or responsibility for management of the water system, or addition of source or storage facilities; and

     (iv) At a minimum the completed WFI shall provide the current names, addresses, and telephone numbers of the owners, operators, and emergency contact persons for the system.

     (v) Purveyors shall provide in the WFI total annual water production and use, including:

     (i) Total annual water production for each source;

     (ii) Monthly and annual totals for water purchased from or sold to other purveyors; and

     (iii) For purveyors with more than one thousand service connections, monthly and annual totals for purveyor consumer classes. Monthly data may be estimated if the water system bills less frequently than monthly.

     (f) Bacteriological.

     (i) The purveyor shall notify the department of the presence of:

     (A) Coliform in a sample, within ten days of notification by the laboratory; and

     (B) Fecal coliform or E. coli in a sample, by the end of the business day in which the purveyor is notified by the laboratory. If the purveyor is notified of the results after normal close of business, then the purveyor shall notify the department before the end of the next business day.

     (g) Systems monitoring for unregulated contaminants in accordance with WAC 246-290-300(9), shall send a copy of the results of such monitoring to the department within thirty days of receipt of analytical results.

     (h) Systems monitoring for disinfection by-products in accordance with WAC 246-290-300(7) shall report information to the department as specified in 40 CFR 141.134.

     (i) Systems monitoring for disinfectant residuals in accordance with WAC 246-290-300(7) shall report information to the department as specified in subsection (2)(a) of this section, and 40 CFR 141.134(c).

     (j) Systems required to monitor for disinfection by-product precursor removal in accordance with WAC 246-290-300(7) shall report information to the department as specified in 40 CFR 141.134(d).

     (k) Systems shall submit to the department, in accordance with 40 CFR 141.31(d), a certification that the system has complied with the public notification regulations (Part 7, Subpart A of this chapter) when a public notification is required. Along with the certification, the system shall submit a representative copy of each type of notice.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-480, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-480, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-480, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-480, filed 3/25/93, effective 4/25/93; 92-04-070 (Order 241B), § 246-290-480, filed 2/4/92, effective 3/6/92; 91-02-051 (Order 124B), recodified as § 246-290-480, filed 12/27/90, effective 1/31/91. Statutory Authority: P.L. 99-339. 89-21-020 (Order 336), § 248-54-265, filed 10/10/89, effective 11/10/89. Statutory Authority: RCW 34.04.045. 88-05-057 (Order 307), § 248-54-265, filed 2/17/88. Statutory Authority: RCW 43.20.050. 83-19-002 (Order 266), § 248-54-265, filed 9/8/83.]

     (a) Giardia lamblia;

     (b) Viruses;

     (c) Heterotrophic plate count bacteria;

     (d) Legionella;

     (e) Cryptosporidium for systems serving at least ten thousand people and beginning January 14, 2005, for systems serving less than ten thousand people; and

     (f) Turbidity.

     (2) For water systems using unfiltered surface sources, in whole or part, and that have been required to install, but have yet to complete the installation and operation of, filtration facilities, the turbidity levels at entry points to distribution and sampling/analytical requirements shall be in accordance with 40 CFR 141.13 and 40 CFR 141.22, respectively.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-601, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-601, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 93-08-011 (Order 352B), § 246-290-601, filed 3/25/93, effective 4/25/93.]

     (2) The purveyor shall install and properly operate water treatment processes to ensure at least:

     (a) 99.9 percent (3 log) removal and/or inactivation of Giardia lamblia cysts;

     (b) 99.99 percent (4 log) removal and/or inactivation of viruses; and

     (c) 99 percent (2 log) removal of Cryptosporidium oocysts if required to filter.

     (3) The purveyor shall ensure that the requirements of subsection (2) of this section are met between a point where the source water is not subject to contamination by untreated surface water and a point at or before the first consumer.

     (4) The department may require higher levels of removal and/or inactivation of Giardia lamblia cysts, Cryptosporidium oocysts, and viruses than specified in subsection (2) of this section if deemed necessary to protect the health of consumers served by the system.

     (5) The purveyor shall ensure that personnel operating a system subject to Part 6 of chapter 246-290 WAC meet the requirements under chapter 70.119 RCW and chapter 246-292 WAC.

     (6) The purveyor of a Group A community system serving water from a surface or GWI source to the public before January 1, 1991, shall comply with applicable minimum treatment requirements. The purveyor shall meet either:

     (a) The filtration and disinfection requirements under WAC 246-290-660 and 246-290-662 respectively;

     (b) The criteria to remain unfiltered under WAC 246-290-690 and the disinfection requirements under WAC 246-290-692; or

     (c) The criteria to provide a limited alternative to filtration under WAC 246-290-691 and the disinfection requirements under WAC 246-290-692.

     (7) The purveyor of a Group A noncommunity system serving water from a surface or GWI source, shall meet either:

     (a) The filtration and disinfection requirements under WAC 246-290-660 and 246-290-662, respectively; or

     (b) The criteria to provide a limited alternative to filtration under WAC 246-290-691 and the disinfection requirements under WAC 246-290-692.

     (8) The purveyor of a Group A system first serving water from a surface or GWI source to the public after December 31, 1990, shall meet either:

     (a) The filtration and disinfection requirements under WAC 246-290-660 and 246-290-662, respectively; or

     (b) The criteria to provide a limited alternative to filtration under WAC 246-290-691 and the disinfection requirements under WAC 246-290-692.

     (9) The purveyor of a system required to install filtration may choose to provide a limited alternative to filtration or abandon the surface or GWI source as a permanent or seasonal source and develop an alternate, department-approved source. Purveyors that develop alternate ground water sources or purchase water from a department-approved public water system using a ground water source shall no longer be subject to Part 6 of chapter 246-290 WAC, once the alternate source is approved by the department and is on line.

     (10) A purveyor that chooses to provide a limited alternative to filtration shall submit an application to the department that contains the information necessary to determine whether the source can meet the criteria.

     (11) If a limited alternative to filtration is provided, then the purveyor shall install and properly operate treatment processes to ensure greater removal and/or inactivation efficiencies of Giardia lamblia cysts, viruses, or other pathogenic organisms of public health concern (including Cryptosporidium oocysts) than would be achieved by the combination of filtration and chlorine disinfection.

     (12) Systems that were required to develop a disinfection profile under 40 CFR 141.172 shall provide that profile and a calculated disinfection benchmark, as described in 40 CFR 141.172 (c)(2) and (3), along with other project information specified in WAC 246-290-110, when proposing any change to the disinfection treatment system. The proposal for change shall include an analysis of how the proposed change will affect the current level of disinfection. The profile must also be available for inspection during routine sanitary surveys conducted under WAC 246-290-416.

     (13) Community and nontransient noncommunity systems serving less than ten thousand persons must meet the disinfection profiling and benchmarking provisions required in accordance with 40 CFR 141.530 through 141.544.

     (14) Systems required to develop a disinfection profile under 40 CFR 141.530 shall provide that profile and a calculated disinfection benchmark, as described in 40 CFR 141.543 along with other project information specified in WAC 246-290-110, when proposing any change to the disinfection treatment system. The proposal for change shall include an analysis of how the proposed change will affect the current level of disinfection. The profile must also be available for inspection during routine sanitary surveys conducted in accordance with WAC 246-290-416.

     (15) A system using conventional, direct, or in-line filtration that must arrange for the conduct of a comprehensive performance evaluation (CPE), in accordance with 40 CFR 141.175 (b)(4) or 40 CFR 141.563, may be required to arrange for comprehensive technical assistance (CTA). The department will determine the need for CTA on a case-by-case basis.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-630, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.20.050. 99-07-021 and 99-10-076, § 246-290-630, filed 3/9/99 and 5/4/99, effective 4/9/99 and 6/4/99; 93-08-011 (Order 352B), § 246-290-630, filed 3/25/93, effective 4/25/93.]

     (a) The purveyor shall ensure that the turbidity level of representative filtered water samples:

     (i) Complies with the performance standards in Table 11(A) until January 14, 2005, and Table 11(B) beginning January 14, 2005; and

     (ii) Never exceeds 5.0 NTU for any system using slow sand, diatomaceous earth((, or));

     (iii) Never exceeds 5.0 NTU for any system serving less than ten thousand people and using conventional, direct, or in-line filtration((.

     (iii))) until January 14, 2005, and never exceeds 1.0 NTU beginning January 14, 2005;

     (iv) Never exceeds 1.0 NTU for any system serving at least ten thousand people and using conventional, direct, or in-line filtration((.));

     (((iv))) (v) Never exceeds the maximum allowable turbidity determined by the department on a case-by-case basis for any system using an alternate filtration technology approved under WAC 246-290-676 (2)(b).

Table 11(A)

TURBIDITY PERFORMANCE REQUIREMENTS (UNTIL JANUARY 14, 2005)

Filtration Technology	Filtered water turbidity (in NTUs) shall be less than or equal to this value in at least 95% of the measurements made each calendar month
	Systems serving < 10,000 people	Systems serving > 10,000 people
Conventional, Direct and In-line	0.50	0.30
Slow Sand	1.0	1.0
Diatomaceous Earth	1.0	1.0
Alternate Technology	As determined by the department through case-by-case approval of technology, in accordance with WAC 246-290-676 (2)(b).

Table 11(B)

TURBIDITY PERFORMANCE STANDARDS (BEGINNING JANUARY 14, 2005)

Filtration Technology	Filtered water turbidity (in NTUs) shall be less than or equal to this value in at least 95% of the measurements made each calendar month
Conventional, Direct and In-line		0.30
Slow Sand		1.0
Diatomaceous Earth		1.0
Alternate Technology	As determined by the department through case-by-case approval of technology, in accordance with WAC 246-290-676 (2)(b).

     (b) The department may allow the turbidity of filtered water from a system using slow sand filtration to exceed 1.0 NTU, but never 5.0 NTU, if the system demonstrates to the department's satisfaction that the higher turbidity level will not endanger the health of consumers served by the system. As a condition of being allowed to produce filtered water with a turbidity exceeding 1.0 NTU, the purveyor may be required to monitor one or more parameters in addition to the parameters specified under WAC 246-290-664. The department shall notify the purveyor of the type and frequency of monitoring to be conducted.

     (2) Giardia lamblia, Cryptosporidium, and virus removal credit.

     (a) The department shall notify the purveyor of the removal credit granted for the system's filtration process. The department shall specify removal credit for:

     (i) Existing filtration facilities based on periodic evaluations of performance and operation; and

     (ii) New or modified filtration facilities based on results of pilot plant studies or full scale operation.

     (b) Conventional, direct, and in-line filtration.

     (i) The removal credit the department may grant to a system using conventional, direct, or in-line filtration and demonstrating effective treatment is as follows:

Percent Removal Credit (log)
Filtration Technology	Giardia		Virus		Cryptosporidium
	Percent	log	Percent	log	Percent	log
Conventional	99.7	2.5	99	2.0	99	2.0
Direct and in-line	99	2.0	90	1.0	99	2.0

     (ii) A system using conventional, direct, or in-line filtration shall be considered to provide effective treatment, if the purveyor demonstrates to the satisfaction of the department that the system meets the:

     (A) Turbidity performance requirements under subsection (1) of this section; and

     (B) Operations requirements of WAC 246-290-654.

     (iii) The department may grant a higher level of Giardia lamblia, Cryptosporidium, and virus removal credit than listed under (b)(i) of this subsection, if the purveyor demonstrates to the department's satisfaction that the higher level can be consistently achieved.

     (iv) As a condition of maintaining the maximum removal credit, purveyors may be required to periodically monitor one or more parameters not routinely monitored under WAC 246-290-664. The department shall notify the purveyor of the type and frequency of monitoring to be conducted.

     (v) The department shall not grant removal credit to a system using conventional, direct, or in-line filtration that:

     (A) Fails to meet the minimum turbidity performance requirements under subsection (1) of this section; or

     (B) Fails to meet the operating requirements under WAC 246-290-654.

     (c) Slow sand filtration.

     The department may grant a system using slow sand filtration 99 percent (2 log) Giardia lamblia cyst and Cryptosporidium oocyst removal credit and 99 percent (2 log) virus removal credit, if the system meets the department design requirements under WAC 246-290-676 and meets the minimum turbidity performance requirements in subsection (1) of this section.

     (d) Diatomaceous earth filtration.

     The department may grant a system using diatomaceous earth filtration 99 percent (2 log) Giardia lamblia cyst and Cryptosporidium oocyst removal credit and 90 percent (1 log) virus removal credit, if the system meets the department design requirements under WAC 246-290-676 and meets the minimum turbidity performance requirements in subsection (1) of this section.

     (e) Alternate filtration technology.

     The department shall grant, on a case-by-case basis, Giardia lamblia cyst, Cryptosporidium oocyst, and virus removal credit for systems using alternate filtration technology based on results of product testing acceptable to the department.

     (f) The purveyor granted no Giardia lamblia cyst removal credit and no Cryptosporidium oocyst removal credit shall:

     (i) Provide treatment in accordance with WAC 246-290-662 (2) (d); and

     (ii) Within ninety days of department notification regarding removal credit, submit an action plan to the department for review and approval. The plan shall:

     (A) Detail how the purveyor plans to comply with the turbidity performance requirements in subsection (1) of this section and operating requirements of WAC 246-290-654; and

     (B) Identify the proposed schedule for implementation.

     (iii) Be considered in violation of the treatment technique specified in WAC 246-290-632 (2)(a)(i) and shall take follow-up action specified in WAC 246-290-634.

     (3) Disinfection by-product precursor removal requirements.

     (a) Conventional systems using sedimentation shall meet the treatment technique requirements for control of disinfection by-product precursors specified in 40 CFR 141.135.

     (i) Applicability of this requirement shall be determined in accordance with 40 CFR 141.135(a).

     (ii) Enhanced coagulation and enhanced softening shall be provided in accordance with 40 CFR 141.135(b), if applicable.

     (iii) Compliance with the treatment technique requirements for control of disinfection by-product precursors shall be determined in accordance with 40 CFR 141.135(c).

     (b) For the purposes of compliance with (a) of this subsection, sedimentation shall be considered applicable when:

     (i) Surface overflow rates and other design parameters are in conformance with traditionally accepted industry standards and textbook values, such as those prescribed in nationally accepted standards, including the most recent version of the Recommended Standards for Water Works, A Committee Report of the Great Lakes - Upper Mississippi River Board of State Public Health and Environmental Managers; and

     (ii) The system has received pathogen removal credit for the sedimentation basin.

     (4) Filter backwash recycling requirements.

     (a) By no later than December 8, 2003, purveyors using conventional, direct, or in-line filtration must report to the department, in writing, whether they recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes within the treatment plant.

     (i) Purveyors that do recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must also report the following information:

     (A) A plant schematic showing the origin of all flows that are recycled (including, but not limited to, spent filter backwash water, thickener supernatant, and liquids from dewatering processes), the hydraulic conveyance (i.e., pipe, open channel) used to transport them, and the location where they are reintroduced back into the treatment plant.

     (B) Typical recycle flow in gallons per minute (gpm), the highest observed plant flow experienced in the previous year (gpm), design flow for the treatment plant (gpm), and the approved operating capacity for the plant.

     (b) By no later than June 8, 2004, purveyors using conventional, direct, or in-line filtration that recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes within the treatment plant shall:

     (i) Return the recycled flow prior to, or concurrent with the location where primary coagulant is introduced into the flow stream.

     (ii) By no later than June 8, 2006, complete any capital improvements (physical modifications requiring engineering planning, design, and construction) necessary to meet the requirements of (b)(i) of this subsection.

     (iii) On a case-by-case basis, the department may approve an alternate location for the return of recycle flows.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-660, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-660, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-660, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-660, filed 3/25/93, effective 4/25/93.]

     (a) The purveyor shall ensure that source water samples of each surface or GWI source are:

     (i) Collected before the first point of disinfectant application and before coagulant chemical addition; and

     (ii) Analyzed for fecal coliform density in accordance with methods acceptable to the department.

     (b) At a minimum, the purveyor shall ensure source samples are collected for fecal coliform analysis at a frequency equal to ten percent of the number of routine coliform samples collected within the distribution system each month under WAC 246-290-300, or once per calendar month, whichever is greater up to a maximum of one sample per day.

     (2) Source turbidity monitoring.

     (a) The purveyor using conventional, direct, or in-line filtration shall measure source turbidity at least once per day on a representative sample collected before disinfection and coagulant addition.

     (b) Grab sampling or continuous turbidity monitoring and recording may be used to meet the requirement specified in (a) of this subsection.

     (c) Purveyors using continuous turbidity monitoring shall record continuous turbidity measurements at equal intervals, at least every four hours, in accordance with a department-approved sampling schedule.

     (d) Purveyors using an approved alternate filtration technology may be required to monitor source water turbidity at least once per day on a representative sample as determined by the department.

     (3) Filtered water turbidity monitoring.

     (a) The purveyor using direct, conventional, or in-line filtration shall:

     (i) Continuously monitor turbidity on representative samples from each individual filter unit and from the system's combined filter effluent, prior to clearwell storage;

     (ii) For systems serving at least ten thousand people, record continuous turbidity measurements from each individual filter unit at equal intervals of at least every fifteen minutes, and for all systems, from the combined filter effluent at equal intervals of at least every four hours, in accordance with a department-approved sampling schedule; ((and))

     (iii) Beginning January 14, 2005, systems serving less than ten thousand people shall record continuous turbidity measurements from each individual filter unit at equal intervals of at least every fifteen minutes;

     (iv) Systems serving less than ten thousand people and consisting of two or fewer filters may record continuous turbidity measurements from the combined filter effluent at equal intervals of at least fifteen minutes in lieu of recording individual filter turbidity measurements; and

     (v) Conduct monitoring in accordance with the analytical techniques under WAC 246-290-638.

     (b) The purveyor using slow sand or diatomaceous earth filtration shall:

     (i) Continuously monitor turbidity on representative samples from each individual filter unit and from the system's combined filter effluent, prior to clearwell storage;

     (ii) Record continuous turbidity measurements from the combined filter effluent at equal intervals of at least every four hours in accordance with a department-approved sampling schedule; and

     (iii) Conduct monitoring in accordance with the analytical techniques under WAC 246-290-638.

     (c) Purveyors using an alternate filtration technology approved under WAC 246-290-676 shall provide monitoring in accordance with the technology-specific approval conditions determined by the department.

     (d) Purveyors using slow sand filtration or an alternate filtration technology may reduce filtered water turbidity monitoring to one grab sample per day with departmental approval. Reduced turbidity monitoring shall be allowed only where the purveyor demonstrates to the department's satisfaction that a reduction in monitoring will not endanger the health of consumers served by the water system.

     (4) Monitoring the level of inactivation and removal.

     (a) Each day the system is in operation, the purveyor shall determine the total level of inactivation and removal of Giardia lamblia cysts, viruses, and Cryptosporidium oocysts achieved.

     (b) The purveyor shall determine the total level of inactivation and removal based on:

     (i) Giardia lamblia cyst, Cryptosporidium oocyst, and virus removal credit granted by the department for filtration; and

     (ii) Level of inactivation of Giardia lamblia cysts and viruses achieved through disinfection.

     (c) At least once per day, purveyors shall monitor the following to determine the level of inactivation achieved through disinfection:

     (i) Temperature of the disinfected water at each residual disinfectant concentration sampling point used for CT calculations; and

     (ii) If using chlorine, pH of the disinfected water at each chlorine residual disinfectant concentration sampling point used for CT calculations.

     (d) Each day during peak hourly flow (based on historical information), the purveyor shall:

     (i) Determine disinfectant contact time, T, to the point at which C is measured; and

     (ii) Measure the residual disinfectant concentration, C, of the water at the point for which T is calculated. The C measurement point shall be located before or at the first consumer.

     (e) The department may reduce CT monitoring requirements for purveyors that demonstrate to the department's satisfaction that the required levels of inactivation are consistently exceeded. Reduced CT monitoring shall only be allowed where the purveyor demonstrates to the department's satisfaction that a reduction in monitoring will not endanger the health of consumers.

     (5) Monitoring the residual disinfectant concentration entering the distribution system.

     (a) Systems serving more than thirty-three hundred people per month.

     (i) The purveyor shall continuously monitor and record the residual disinfectant concentration of water entering the distribution system and report the lowest value each day.

     (ii) If the continuous monitoring equipment fails, the purveyor shall measure the residual disinfectant concentration on grab samples collected at least every four hours at the entry to the distribution system while the equipment is being repaired or replaced. The purveyor shall have continuous monitoring equipment back on-line within five working days following failure.

     (b) Systems serving thirty-three hundred or less people per month.

     (i) The purveyor shall collect grab samples or use continuous monitoring and recording to measure the residual disinfectant concentration entering the distribution system.

     (ii) Purveyors of community systems choosing to take grab samples shall collect:

     (A) Samples at the following minimum frequencies:

Population Served				Number/day
25	-	500		1
501	-	1,000		2
1,001	-	2,500		3
2,501	-	3,300		4

     (B) At least one of the grab samples at peak hourly flow; and

     (C) The remaining samples evenly spaced over the time the system is disinfecting water that will be delivered to the public.

     (iii) Purveyors of noncommunity systems choosing to take grab samples shall collect samples for disinfectant residual concentration entering the distribution system as directed by the department.

     (iv) When grab samples are collected and the residual disinfectant concentration at the entry to distribution falls below 0.2 mg/L, purveyors shall collect a grab sample every four hours until the residual disinfectant concentration is 0.2 mg/L or more.

     (6) Monitoring residual disinfectant concentrations within the distribution system.

     (a) The purveyor shall measure the residual disinfectant concentration at representative points within the distribution system on a daily basis or as otherwise approved by the department.

     (b) At a minimum, the purveyor shall measure the residual disinfectant concentration within the distribution system at the same time and location that a routine or repeat coliform sample is collected in accordance with WAC 246-290-300(3) or 246-290-320(2).

     (c) The purveyor may measure HPC within the distribution system in lieu of measuring the residual disinfectant concentration in accordance with this subsection.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-664, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-664, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-664, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-664, filed 3/25/93, effective 4/25/93.]

     (a) A waterborne disease outbreak potentially attributable to the water system occurs;

     (b) The turbidity of the combined filter effluent exceeds 5.0 NTU at any time for any system using slow sand, diatomaceous earth, or for any system serving less than ten thousand people and using conventional, direct, or in-line filtration;

     (c) The turbidity of the combined filter effluent:

     (i) Exceeds 1.0 NTU at any time for a system serving at least ten thousand people and using conventional, direct, or in-line filtration;

     (ii) Beginning January 14, 2005, the turbidity of the combined filter effluent exceeds 1.0 NTU at any time for a system serving less than ten thousand people using conventional, direct, or in-line filtration;

     (d) The turbidity of the combined filter effluent exceeds the maximum specified level for an alternative filtration technology approved by the department;

     (e) The residual disinfection concentration falls below 0.2 mg/L at the entry point to the distribution system. The purveyor shall also report whether the residual was restored to 0.2 mg/L or more within four hours; or

     (f) An event occurs that may affect the ability of the water treatment facility to produce drinking water that complies with this chapter including, but not limited to:

     (i) Spills of hazardous materials in the watershed; and

     (ii) Treatment process failures.

     (2) The purveyor shall report results of monitoring conducted in accordance with WAC 246-290-664 to the department. Monthly report forms shall be submitted within ten days after the end of each month the system served water to the public.

     (3) The purveyor shall report, at a minimum, all the information requested by the department using a department-approved form or format including:

     (a) Water treatment facility operations information;

     (b) Turbidity monitoring results, including:

     (i) Source monitoring, if required under WAC 246-290-664(2);

     (ii) Combined filter effluent. Continuous measurements shall be reported at equal intervals, at least every four hours, in accordance with a department-approved schedule;

     (iii) Individual filter turbidity monitoring results. Systems serving at least ten thousand people and using conventional, direct, or in-line filtration shall report and take follow-up action as prescribed in 40 CFR 141.175(b). Beginning January 14, 2005, systems serving less than ten thousand people shall report and take follow-up action as prescribed by 40 CFR 141.563 and 141.570. Required follow-up action may include development of a filter profile, a filter self-assessment, as described in 40 CFR 141.175 (b)(((4)))(3) and 141.563(b), or the completion of a comprehensive performance evaluation (CPE).

     (c) Disinfection monitoring information including:

     (i) Level of inactivation achieved;

     (ii) Residual disinfectant concentrations entering the distribution system; and

     (iii) Residual disinfectant concentrations within the distribution system.

     (d) Total level of removal and inactivation; and

     (e) A summary of water quality complaints received from consumers served by the water system.

     (4) A person certified under chapter 246-292 WAC shall complete and sign the monthly report forms required in this section.

[Statutory Authority: RCW 43.20.050 (2) and (3) and 70.119A.080. 03-08-037, § 246-290-666, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-666, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-666, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-666, filed 3/25/93, effective 4/25/93.]

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