1993 Septic system design & permit

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DESIGN REOtllRKMKN IS Considering the soil data and minimum design requirements of the Septic System Ordinance, our proposal is as tbllows: Construct a Mound System based on a water usage of900 gallons per day, for a 6 bedroom ty|x; I. 900 gpd X .83 sq. ft. gppd = 747 sq. ft. bed area-minimum design size. Proposed Design Size 10' x 75' bed = 750 sq. It. bed area 2- 1250 gal. tank 1- 1250 gat. pump tank CONSTRDCIION 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. 1 he trench e.xcavated to install the discharge pipe shall be carefully backfilled and compacted to prevent seepage of elllucnt. The total area selected Ibr 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 la> er of the mound, fhe 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 e nl below which the soil may be manipulated for pur|X)ses of installing a soil treatment system, and above which manipulation will cause compaction and puddling. Surface preparation or scarification will be jK'rlbrmed 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. Construction Materials & Di.stributiun of Effluent A clean washed sand layer shall be placed where the filter (rock bed) material is to be U.cated. This sand layer must be at least 13-inches deejv and sliould 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