1993 Septic system design & permit

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DESIGN RFOiriRFMENTS Considering the soil data and minimum design requirements of the Septic System Ordinance, our proposal is as follows; Construct a Mound System based on a water usage of 900 gallons per day, for a 6 bedroom type 1. 900 gpd X .83 sq. ft. gppd = 747 sq. ft. bed area-minimum design size. Proposed Design Size 10' x 75* bed 750 sq. ft. bed area. 2- 1250 gal. tank !• 1250 gal. pump tank CONSTRUCTION PRQCEDCIIE FOR A SEWAGE TREATMENT MOUND Soil Surface preparation A 2 inch discharge pipe from the pump to end of the mound area shall be installed prior to soil surface preparation. The trench excavated to install the discharge pipe shall be carefully backfilled and compacted to prevent seepage of effluent. The total area selected for the mound, including that under the dikes, shall be roughened in order to thoroughly break up any existing sod layers and to provide a suitable transition zone between the original soil and the sand layer of the mound. The area shall be roughened only when the moisture content of the soil 8 inches below the surface is drier than the plastic limit. The plastic limit is the soil moisture content below which the soil may be manipulated for purposes of installing a soil treatment system, and above which manipulation will cause compaction and puddling. Surface preparation or scarification will be performed with a back-hoe bucket. There shall be no dead furrow in the mound construction area. Mound construction shall proceed immediately after surface preparation is completed. Every effort should be taken to prevent rain from falling on the prepared soil surface. Gon-tfriictlon Malerialii A Diatribution of Effluent A clean washed sand layer shall be placed where the filter (rock bed) material is to be located. This sand layer must be at least 13>inches deep and should be deep enough to level area for mound. A crawler tractor with a blade or bucket shall be used to move the sand into place. At