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§ 4.2 Considering the area has been intensely farmed for the past several decades, the nitrate concentration would be expected to be high in the tested domestic well. This nitrate concentration shows that downward migration of nitrate occurs, but actually could be much higher, indicating there may be attenuation by denitrification and/or underlying clay strata. TABLE 2 WELL WATER ANALYSIS WELL ANALYTE CONCENTRATION FOUND MAXIMUM CONTAMINANT LEVEL (MCL1 Domestic Well at 15655 Mitchell Road Nitrate (As Nitrogen) 9.35 ppm 10 ppm Dibromochloropropane . DBCP and EDB ND 0.2 p11_, § 7.0 CONCLUSIONS The percolation test results for all four proposed Parcels demonstrate acceptable permeability for the management of current and future effluent flows from the existing and proposed OWTS structures. As noted from the perc test results, as the soil becomes increasingly saturated, the percolation rate decreases and occasionally fluctuates. The EHD requires there be sufficient distance for treatment of septic effluent before it encounters the groundwater table. This minimum soil depth from the bottom of the dispersal system to the water table is based upon the perc test results. Since the perc tests ranged between 5 minutes per inch (mpi) and 30 mpi, an 8 ft minimum separation distance must be maintained. Based upon the highest depth to the water table (determined to be 20 ft bgs), sufficient distance exists between the bottom of the OWTS structure and the groundwater depth. § 6.8 Although there is no proposal to build an accessory unit dwelling on proposed Parcel 4, or a primary dwelling on the remaining Parcels, an OWTS design for any future development will be dependent upon the number of bedrooms within a new structure. Leachline length in this locale is stipulated by EHD to be 80 ft for each bedroom. Determination of a bedroom is made by closets. If a room has a closet, it is designated as a bedroom. A filter bed area can also be calculated, if so desired. § 6.7 No problems are anticipated for any future septic system on the Parcels, other than typical lifespan concerns. An engineered OWTS will not have to be installed for this project unless there is an exceedance of nitrate loading standards as discussed in the Introduction. Any new system must have at least a 100% replacement area incorporated into the design. It is important to recognize that all OWTS have a lifespan, which is dependant on several factors and is therefore difficult to determine. Septic system leachline failure would primarily result from the advanced formation of a "biomat" or "clogging mat" on the wetted soil-effluent interface. Page -4- Chesney Consulting