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Article I. General Provisions
13.20.010 Responsibility for onsite wastewater system.
Article II. Compliance Criteria
13.20.030 Compliance with wastewater system requirements.
13.20.040 Onsite wastewater systems to comply with rules.
13.20.050 Onsite wastewater system design and type considerations.
13.20.060 Types of treatment available to onsite wastewater systems.
13.20.070 Wastewater to receive primary treatment prior to discharge to absorption system.
13.20.080 Wastewater not allowed to surface on ground or enter state waters—Exception.
13.20.090 Wastewater not to be discharged into unused wells, gravel pits, or rock formations.
13.20.100 Drainage not to enter wastewater systems.
13.20.110 Protection of potable water supply.
13.20.120 Onsite wastewater system prohibited when public wastewater systems are available.
13.20.130 Review of plans prior to onsite wastewater system construction permit approval.
Article III. Site Evaluation Requirements
13.20.140 Determination of acceptability of lot or site to support onsite wastewater system.
13.20.150 Separation required above ground water or geological formations.
13.20.160 Minimum lot size required.
13.20.170 Distance between onsite wastewater system components and pertinent ground features.
13.20.180 Onsite wastewater system construction permit application requirements.
13.20.190 Compliance with any other provisions of law.
13.20.200 Completed site plan.
13.20.210 Percolation tests required prior to approval and installation of absorption system.
13.20.220 Soil observation pits and soil borings.
13.20.230 Ground water determination.
13.20.240 Field evaluation.
13.20.250 Site evaluations during the platting stages.
Article IV. Sensitive Regional Areas
13.20.260 Sensitive regional areas—Scope.
13.20.270 Alterations in sensitive areas.
13.20.280 Design criteria for sensitive regional areas for new or repaired onsite wastewater systems.
Article V. Design Flow Determination
13.20.290 System sizing.
13.20.300 Design flow.
13.20.310 Wastewater flow capacity requirements of residential and non-residential establishments.
13.20.320 Alternative method of determining wastewater flow capacity requirements for commercial or public service establishments.
13.20.330 Alternative method of determining wastewater flow capacity requirements for public parks and marinas.
Article VI. Septic Tanks
13.20.340 Design and construction requirements for septic tanks.
13.20.350 Minimum capacities for septic tanks.
13.20.360 Installation requirements for septic tanks.
Article VII. Treatment of Effluent
13.20.370 Distribution of septic tank effluent to absorption fields.
13.20.380 Distribution pipes.
13.20.390 Gravity distribution.
13.20.400 Additional requirements for drop boxes, distribution boxes, or valve boxes.
13.20.410 Dual field systems.
13.20.420 Dosing or pressure systems required when absorption systems are large.
13.20.430 Dosing of effluent.
13.20.440 Dosing chamber, pump pit, wet well, or lift station.
13.20.450 Dosing devices for gravity distribution.
13.20.460 Dosing devices for pressure distribution.
13.20.470 Determining required absorption system area.
13.20.480 Alternative method of determining required absorption trench system area.
13.20.490 Class II dwelling sizing factors.
13.20.500 Requirements for absorption trenches.
13.20.510 Gravelless systems.
13.20.520 Chamber systems.
13.20.530 Requirements for absorption beds.
13.20.540 Additional criteria for design and construction of absorption systems.
13.20.550 Requirements for a mound or evapotranspiration system.
13.20.560 Requirements for graywater system.
Article VIII. Alternative or Unconventional Systems
13.20.570 Holding tanks.
13.20.580 Requirements for vault privies.
13.20.590 Requirements for unconventional systems.
13.20.600 Unconventional systems to be used when water or electrical systems unavailable.
13.20.610 Absorption or alternative water-carriage system permitted under certain circumstances.
13.20.620 Seepage pits allowable.
13.20.630 Cesspool, pit privy or other failing systems.
Article IX. State and Local Policies
13.20.650 Disposal of septage.
13.20.660 Abandoned systems to be disconnected, plugged, dismantled, pumped, removed, and filled.
Article X. Management and Administration
13.20.720 Interagency coordination.
13.20.730 Alternative systems.
13.20.740 Wastewater disposal.
13.20.750 Abandonment of onsite domestic wastewater disposal systems.
13.20.760 Standards applicability.
13.20.780 Additional factors affecting the application process.
13.20.790 System observations.
13.20.800 Sewerage system permits.
13.20.810 Operations and maintenance requirements.
13.20.820 Materials prohibited in on-site wastewater facilities.
13.20.830 Appeal procedure.
13.20.840 Waiver of regulations.