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A. Complete the application for an on-site sewage disposal system permit form including, but not limited to:

1. Directions to the subject property (include vicinity map if needed);

2. Address or approximate address of property;

3. Name of current owner and name of system designer;

4. Type of building proposed. If other than single-family residence, include estimated daily wastewater flow;

5. Classifications used for logs of subsurface soil conditions shall be in USDA Soil Conservation Service terminology such as sandy loam, clay loam, medium sand, hardpan, rock, etc. Any evidence of a seasonal water table including color and mottling must be noted and described. These soil log notes must be attached to the application for review and verification.

6. Source of Domestic Water.

a. If public water (any source other than an individual supply serving one single-family residence) is provided, identify by name and include a letter from the purveyor confirming water availability and commitment to serve.

b. If an individual water supply (well) is proposed, the proposed well site must be shown on the design in relation to the proposed drainfield areas. In addition, a well site application (detailing the well site and its 100-foot pollution control zone) may be submitted for concurrent review.

7. Trench depth, width and required square footage of drainfield laterals.

8. If an alternative system is proposed, include all information, construction details, calculations, etc., as required in the DOH Guideline as well as any specific SHD requirement.

9. Signature of designer and date of field testing.

10. Any redesign submittals reflecting changes to the application cover sheet must be accompanied by a new, original carbon application form (not copies).

B. Complete and submit four copies of an on-site sewage disposal system design and plot plan and include:

1. The plot plan is to be dimensioned and drawn to a scale which shows one inch to be equal to no more than 30 feet. Indicate compass direction by using a north arrow. If the entire parcel/lot cannot be included on a one inch equals 30 feet scale, an overall plot plan of the lot including location of residence, drainfield and easement (if proposed) shall be required in a smaller scale in addition to the one inch equals 30 feet (i.e., one inch equals 100 feet).

2. If a short plat is proposed an overall plot plan indicating the layout of the lots (in relation to each other) shall be submitted in addition to the individual designs.

3. Show elevations at soil test holes and topographical contours at two feet intervals in the drainfield and reserve area.

4. Show wells, other sources of potable water and other surface water bodies within 100 feet of property lines.

5. Identify and show location of soil test holes.

6. The proposed on-site sewage disposal system and proposed site of the structure shall be located by giving dimensions to at least two intersecting property lines. Show driveway parking and any other proposed paving locations.

7. Any proposed well site shall be shown together with the minimum circular area of protection having a radius no less than 100 feet.

8. Construction plan specifications to include:

a. Plumbing stub-out elevation in relation to a documented reference point.

b. A minimum and maximum trench depth.

c. An expected amount of cover soil required.

d. The lateral lengths and method of distribution.

e. Location of interceptor, curtain or footing drains, dosing system specifications, etc.

9. Show all required separations as required by WAC 246-272A-0210, Location.

10. All drainfield laterals shall be shown as dashed lines, with tightlines shown as solid lines.

11. Reserve area boundaries shall be labeled and shown by outlining, or by shading of the area or showing the laterals using double dashed lines and identifying as reserve.

12. If an alternative system is proposed include all information, construction details, calculations, etc., as required in the applicable DOH guideline together with any specific SHD requirements.

13. Design on sloping sites greater than 10 percent shall include a trench/slope cross-section detail demonstrating compliance with minimum vertical separation and trench depth requirements. [Res. 08-10. Revised and reapproved by DOH 12/15/94. Res. 93-32, Eff. 11/09/93. Prior code § 8.6(III)].