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FrSEPTICNKS affect the sludge, scum and effluent volumes, which in turn affect treatment of hin the tanks. Typically,the volumetric capacity of septic tanks serving commercial uld be equal to approximately 5 times the average daily flow(ADF or QAvE). In the following equations,the numerical value times the QA, and the peaking value (PF) correlate with the pump-out time interval in years. The peaking value is normally taken to be 1.5 for commercial projects. SEPTIC TANK CAPACITY EXAMPLE FOR THE EXISTING FACILITY: Recommended tank capacity for a pump-out interval of once a year: 2.0(QAvF) x Peaking Factor (PF)=2.0(340 people x 15 gals/day= 5,100 gals/day)x 1.5 = 15,300 gal tank capacity required. There are eight - 1600 gallon tanks and one 1200 gallon pump station= 14,000 gallons. FILTER BEDS FILTER BED EXAMPLE FOR THE EXISTING FACILITY: 14,000 gallon septic tank capacity. Therefore, the Base Tank Capacity = 14,000 gal: Base Tank Capacity (BTC)+Average Daily Flow(ADF)x Soil Factor(SF)= 14,000 gal BTC +(340 people x 15 gallons= 5,100 ADF)= 19,100 x 0.225 SF =4,300 lineal ft of L.L. FILTER BED REQUIREMENT=4,300 LFLL x 4= 17,200 sq ft or 131 feet square. EXISTING FILTER BEDS (2) =250 FEET x 500 FEET= 125,000 SQ FT. (2.87 Ac) III. CONCLUSIONS The Nitrate Loading Study calculations suggest that the resultant average concentration of nitrate in the effluent recharge water emanating from the on-site filter beds is equivalent to the current nitrate concentration in the water table upgradient from the filter bed. This determination is based upon "factors of safety" incorporated into the calculations, and the fact that the nitrate loading considers the entire area of the facility. From the analytical test results, it was determined that both thesnil profile and the underlying groundwater table contain high concentrations nf__ +*a+P»nor narce1255-26-13.� It is assumed that these quantitative determinations are representative of the entire subject parcel. These nitrate concentrations have primarily originated from agricultural fertilizer inputs. However, it may be that an unknown percentage of the nitrate found in the water table may be originating from the alfalfa. In my opinion, there are three significant beneficial issues regarding the proposed development of parcel 255-26-13 into a Truck Stop. First, EHD will require that the septic system installed for this project will have to provide additional effluent treatment above what a conventional septic system would offer. 10 Cliemey CmLq&ing