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1200 BTC+ 180 ADF= 1380 gallons 1380 x 0.25 (clay soils)=345 LFLL(Lineal Feet of Leachline)Required. Therefore: 3 x 50 feet leachline= 150 feet 3 x 36 inch dia. seepage pits= 3 x 70 equivalent feet of LL=210 feet 210 feet of LL+ 150 feet of LL=360 feet of LL(345 LFLL required.) re' III. CONCLUSIONS AND RECOMMENDATIONS From the USDA Soil Map aerial photo, it can be noted that the mobile home park to the south and the pre-existing drive-in theater to the north are crossgradient with respect to groundwater flow to the subject property. Agricultural production land to the west is upgradient to the subject property. In all probability,these land uses have contributed, and are currently contributing nitrate to the groundwater. Given the vast majority of upgradient land use in proximity to the property is, or was in agricultural production, a higher percentage of nitrate may be originating from this source in comparison to crossgradient septic effluent influence. However, without highly sophisticated testing and modeling, it would be impossible to determine the percentages each source contributes to the nitrate concentration that was observed in the on-site well that was tested. Unfortunately,no well log was available for this well. From the attached well replacement permit, the well is 152 feet deep with the pump set at 120 feet. The percolation test results show soils at the typical leachline depth are soils with marginal percolative capability under saturated conditions. Therefore, seepage pits are warranted and must be used for this project. The perc test results obtained from the deep perc tests also indicate marginal soils for percolative capacity. The Long Term Acceptance Rate(LTAR) for the leachlines and seepage pits correlated with the perc rates obtained are as follows: Leachlines=50 min/in=0.417 gallons/ft2/day Seepage Pits=27 min/in= 0.580 gallons/ft/da) /Therefore,the LTAR for each 50 foot long leachline with two foot square on each sidewall and two feet on the floor of trench=4 sq ft/foot x 50 feet/leachline x 3 leachlines x 0.417 gallons/ft/day=250 gallons per day J absorbed by the three leachline trenches. Each 36" pit=243 ftZ/3 ft dia. x 3 pits x 0.580 gallons/ft2/day=423 gallons per day absorbed by the three l seepage pits. Total=250+423 =673 gallons theoretically absorbed per day. \ Calculated average daily flows= 180 gals effluent generated/day. It is recommended that leachlines trench sidewalls be opened with teeth on the sides of the backhoe bucket. The teeth on the cutting edge of the bucket can be used to open the floor of the trenches to the maximum extent possible. This will allow effluent infiltration and percolation within the leachline trenches and promote denitrification within the anaerobic micro sites of the clay soil. Contemporary scientific literature suggests that denitrification may be enhanced by placing the leachlines high in elevation toward the soil surface. However, it is unknown at this time if there will be excessive fall which may exceed leachline trench depth. The effluent may have to be pumped to the disposal area. 7 Chesney Consulting