Washington Administrative Code

A person removing septage from an OSS shall obtain approval from the local health officer before removal and:(1) Transport septage or sewage only in vehicles clearly identified with the name of the business and approved by the local health officer;(2) Record and report septage re…

(1) Prior to approving any development, the local health officer shall:(a) Require site evaluations under WAC 246-272A-0220;(b) Require information consisting of field data, plans, and reports supporting a conclusion that the proposed land area is sufficient to:(i) Install confor…

(1) OSS installers, pumpers, and maintenance service providers shall obtain approval from the local health officer prior to providing services including, but not limited to, conducting inspections in accordance with WAC 246-272A-0260 and 246-272A-0270, within a local health juris…

The department shall:(1) Maintain a TAG to advise the department regarding:(a) OSS design and siting;(b) Public domain technologies, DS&G for product use; and(c) Testing and design standards used for proprietary product registration and DS&G for use of proprietary products.(2) Se…

The department shall:(1) Maintain a policy advisory group to:(a) Make recommendations concerning OSS departmental policy and rules;(b) Review OSS program services; and(c) Provide input to the department regarding the OSS program;(2) Select members for three-year terms from agenci…

(1) The local health officer may grant a waiver from specific requirements of this chapter. A request for waiver must be:(a) Evaluated by the local health officer on an individual, site-by-site basis;(b) Consistent with the purposes of this chapter.(2)(a) The local health officer…

The department shall review this chapter to evaluate the effectiveness of the rules, determine where revisions may be necessary, and make recommendations to the state board of health and all local health officers by September 2026 and every four years thereafter.[Statutory Author…

(1) When an OSS is out of compliance with any law or rule regulating OSS and administered by the department or the local health officer, the department or the local health officer may initiate enforcement action. Enforcement action may include, but is not necessarily limited to:(…

(1) All local boards of health shall:(a) Maintain an adjudicative process to resolve procedural and technical conflicts arising from the administration of local regulations; and(b) Establish rules for conducting hearings requested to contest a local health officer's actions.(2) T…

If any provision of this chapter or its application to any person or circumstances is held invalid, the remainder of this chapter, or the application of the provision to other persons or circumstances shall not be affected.[Statutory Authority: RCW 43.20.050. WSR 05-15-119, § 246…

(1) The purpose of this chapter is to protect public health and the environment by establishing a comprehensive framework for statewide management of LOSS.(2) This chapter implements chapter 70A.115 RCW by establishing regulations for LOSS owners, operators, design engineers, and…

The following acronyms and definitions apply throughout this chapter unless the context clearly requires otherwise:(1) "Additive" means a commercial product added to an OSS intended to affect performance or aesthetics of an OSS.(2) "ASTM" means American Society for Testing and Ma…

(1) This chapter applies to all LOSS constructed, operated, and maintained in the state of Washington, except for:(a) Systems receiving industrial wastewater discharges;(b) Systems receiving stormwater discharges;(c) Combined sanitary sewer and stormwater systems;(d) Evaporative …

(1) Persons may not install or operate a LOSS without an operating permit as provided in this chapter.(2) Owners shall obtain an operating permit from the department and shall renew it annually.(3) LOSS permitted prior to the effective date of this chapter, that do not fully comp…

(1) The owner proposing a new LOSS shall submit to the department:(a) A copy, in electronic format acceptable to the department, of the predesign report that meets the requirements of WAC 246-272B-03000 that is prepared, stamped, signed, and dated by a design engineer; and(b) The…

(1) Upon receiving the notice to proceed, the owner may proceed with the environmental review. To proceed, the owner shall submit an SRS that meets the requirements of WAC 246-272B-03200.(2) After reviewing all submitted information, the department shall provide a written notice …

(1) Upon receiving the department determination that the HGR contains sufficient information to determine the public health and environmental impacts of the LOSS and the LOSS is feasible, the owner may proceed with engineering. To proceed, the owner shall submit a copy, in electr…

(1) To apply for an operating permit, the owner of a LOSS with design flow of 14,500 gpd and below shall submit a completed operating permit application on a form provided by the department; the operating permit fee established in chapter 246-272 WAC, Wastewater and reclaimed wat…

(1) To apply for an operating permit, the owner of a LOSS with a design flow greater than 14,500 gpd shall complete and submit an operating permit application on a form provided by the department; the operating permit fee established in chapter 246-272 WAC, Wastewater and reclaim…

(1) Within one year of receiving the notice of determination under WAC 246-272B-02200 (2)(a), the owner may proceed with public notice. To proceed, the owner shall provide public notice that meets the requirements of this section prior to receiving department approval to construc…

(1) The department shall consider comments received within thirty days of the first published public notice required by WAC 246-272B-02250, and may:(a) Require additional information from the owner;(b) Require changes to the LOSS design, O&M manual, or management plan; or(c) Modi…

(1) The owner may not begin construction until receiving the department's written approval to construct.(2) After receiving approval to construct, the owner shall annually apply to renew the operating permit.(3) If construction does not begin within two years following the date o…

(1) The owner of a LOSS constructed on or before July 1, 1984, who does not have an operating permit issued by the department shall submit:(a) A completed application on a form provided by the department;(b) Copies of all available design and construction documentation, including…

(1) The owner of a LOSS permitted by the department of ecology or local health jurisdiction shall continue to maintain a current permit and meet its terms and conditions until the department issues a LOSS operating permit.(2) The department shall notify the owner when to submit a…

(1) The owner of a LOSS constructed after July 1, 1984, that does not have an operating or discharge permit from the department, department of ecology, or local health jurisdiction shall submit:(a) An operating permit application on a form provided by the department;(b) Copies of…

(1) When a LOSS owner proposes a modification to the design, operation, or physical facilities, or when the department requires the owner to make such a modification, the owner shall consult with the department to determine the appropriate site review, environmental review, or en…

(1) The owner shall submit a completed operating permit renewal application, annual report, all other information required by the department, and the annual permit fee established in chapter 246-272 WAC, Wastewater and reclaimed water use fees, to the department at least thirty d…

(1) The department shall issue a LOSS operating permit for the LOSS and owner named in the application.(2) The department may issue a new operating permit when there is a change in LOSS ownership or management, according to WAC 246-272B-02550.(3) LOSS owners shall employ one or m…

At a minimum, the predesign report must include the following information:(1) Contact information for the owner and design engineer;(2) Site address, legal description, and name of the county where the project is located;(3) Vicinity map showing:(a) The project site;(b) Project p…

(1) The owner shall prepare test pits that are open and available for inspection, and meet the requirements of WAC 246-272B-03400.(2) The owner shall provide a means for safe ingress and egress and is responsible for constructing, maintaining, and closing test pits in a safe mann…

At a minimum, the SRS must include the following information:(1) Design flow and waste strength.(2) A description of the physical characteristics of the primary and reserve drainfield site including:(a) Predominant soil type;(b) Vertical separation; and(c) Water table.(3) Identif…

(1) The department will determine the scope of the HGR based on the site conditions identified in the SRS, if one has been completed.(2) If an SRS has not been completed, the owner shall include the information listed in WAC 246-272B-03200 in the HGR.(3) The HGR must include suff…

(1) The owner shall install enough test pits to characterize soil type and conditions across both the primary and reserve drainfield areas.(2) Each test pit must be:(a) Prepared so the soil profile can be viewed in original undisturbed position to a depth of at least three feet d…

(1) To manage nutrient loading, and in addition to any nutrient reduction treatment required by the department based on the SRS or HGR prepared under WAC 246-272B-03200 and 246-272B-03300, the owner shall dedicate a minimum land area for the total development served by the LOSS a…

(1) The engineering report must outline the scope of the LOSS project, provide necessary background information, the design guidance or standards used, calculations for developing plans and specifications, and impact on public health and the environment.(2) The engineering report…

(1) The management plan must include, at a minimum:(a) A statement identifying whether the ownership of the development served by the LOSS is:(i) A single owner; or(ii) A collection of individually owned lots or units.(b) If a development has individually owned lots or units, a s…

The O&M manual must include the following information:(1) Name, telephone number, fax number, mailing address, and email address for the following:(a) Operator;(b) Owner;(c) Design engineer;(d) Installer;(e) Electrician;(f) Pumper;(g) Management entity;(h) Primary contact person …

At a minimum, the monitoring and reporting plan must include:(1) Constituents of the sewage or effluent that must be tested to assure that treatment components are meeting treatment level requirements, and to monitor groundwater or surface water:(a) As required by the department;…

(1) Construction plans and specifications must be clear and detailed documents and in an electronic format acceptable to the department.(2) Plans must include the following:(a) Design flow, treatment level, drainfield and tank sizing, and hydraulic loading rate;(b) LOSS schematic…

The installer shall:(1) Be currently approved by the local health jurisdiction in the county where the LOSS is to be constructed.(2) Have the following experience:(a) Three or more years experience installing OSS; or(b) A record of successful completion of at least one similar in…

The design engineer or the engineer's authorized representative shall:(1) Conduct inspections to:(a) Verify LOSS construction and materials conform with approved plans and specifications; and(b) Collect data for the record drawings.(2) Inspect the following:(a) Poured-in-place se…

The design engineer shall verify that all sewage tanks used in the LOSS are tested for water tightness by either vacuum testing or water-pressure testing.(1) Vacuum testing steps:(a) Seal the empty tank;(b) Temporarily seal access openings, risers, and inlet and outlet pipes; and…

(1) The department shall conduct a final inspection for all LOSS and witness a pressure test of the drainfield prior to cover except for LOSS with subsurface drip systems.(2) The department may accept baseline pressure and flow information from the design engineer in lieu of witn…

Post-construction documents must include the following:(1) A LOSS construction completion report prepared by the design engineer that:(a) Is on a form provided by the department;(b) States the LOSS was constructed in substantial accordance with the approved plans and specificatio…

(1) Design engineers shall use design criteria detailed in this chapter and from generally accepted guidance and standards when designing LOSS.(2) All sewage from a building served must be directed to the LOSS, unless the LOSS permit allows another option.(3) LOSS must be designe…

(1) The design engineer shall design the LOSS and verify it is installed in compliance with the minimum horizontal setbacks shown in Table 3 of this section.(2) The design engineer shall increase the separation distance between the LOSS and a public drinking water well, spring, o…

(1) A vertical separation of at least three feet is required between the infiltrative surface of the drainfield bed or trench and:(a) The highest seasonal water table;(b) A restrictive layer; or(c) Soil types 6 or 7.(2) The department may allow a reduction of vertical separation …

(1) The design engineer shall use the following minimum design flows, which include the appropriate peaking factors, for developments or portions of developments serving residential facilities such as single-family residences, multi-family dwellings, and mobile home parks with to…

(1) The design engineer shall identify sewage characteristics in terms of the following:(a) CBOD5, TSS, O&G, BOD5, and fecal coliform bacteria;(b) Other parameters that can impact treatment anywhere in the treatment sequence including, but not limited to, pH, temperature and diss…

(1) Treatment to produce effluent of a higher quality than STE is required when:(a) LOSS conditions match those in Table 6 of this section that require minimum Treatment Levels E, C, B, HQE, N10, N20, or P;(b) Sewage characteristics exceed typical values expected from residential…