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IV. CONCLUSIONS AND RECOMMENDATIONS SSS§5.4. The soils underlying the proposed leachfield disposal area to serve the expansion facility of the Sunset Kennels show medium permeability at the typical filter bed depth of 36 inches, and exceptional permeability at the deeper depth of seven feet. By installing the filter bed exclusively without deeper septic system structures, a 10-foot separation distance between the floor of the filter bed and the water table as measured by sounding the domestic well is easily achieved. N NLS§4.2, SSS§ 6.7. From the soil chemistry test results, it appears that denitrification potential will be low-to-medium based upon the clay content and the increase in nitrate-nitrogen content through the soil profile. This denitrification potential in combination with comparatively shallow- rooted landscape plants such as grasses in the leachfield area should also reduce potential nitrate impact by evapotranspiring and mineralizing a percentage of the effluent during favorable weather times of the year(i.e.,April through September). SSS§6.8. The Average Daily Flow is calculated to be 280 gpd from the proposed kennel expansion facility. The Application Rate at the native soil-effluent interface is 0.52 gals/ft2/day from the obtained perc rate of 35.7 min/in at the 36-inch perc test depth. Given that the floor of the filter bed(excluding walls) is 18 ft x 56 ft= 1008 sq. ft. 1008 sq. ft x 0.52 gals/ft'/day= 524 gals/day of effluent acceptance. This exceeds the estimated daily wastewater flow by: 524 gpd- 280 gpd=244 gallons per day. The Long-term Acceptance Rate(LTAR) is estimated to be 0.20 gals/ft2/day. Taking the filter bed sq. ft= 1008 sq. ft x 0.20 gals/ft'/day=202 gals/day of effluent acceptance. By adding the walls of the filter bed to a height of one ft, we find the total infiltrative area increases to 1,156 sq. ft. 1,156 sq. ft x 0.20 gals/ft /day=231 gallons, which is under the 280 ADF. The reserve area may have to be activated at this time. NLS§4.1. The nitrate loading potential cal ed on Page 9 indicates the percolating effluent may have a resultant nitrate concentration of 35.4 as nitrate, which is below the drinking water Maximum Contaminant Level (MCL = p The shallow underlying groundwater aquifers contain a nitrate concentration of approximately 76 ppm nitrate, based upon the water analysis of an old on-site well that has subsequently been destroyed. Consequently, the recharge effluent water may theoretically add a dilution effect to the top aquifer(s). Sprinkler irrigation over both disposal areas must be carefully considered so as to not inundate the leachfield. During the spring and summer months, irrigation should be done intermittently during the day and/or evening hours. For example, the sprinklers could run for five minutes, six times per day. Irrigation during the wintertime should be suspended. Another source of nitrate loading can be from the lawn or other landscape-type plants that may be planted over the leachfield area. It is recommended not to use any nitrogen fertilizer in these areas. If it is deemed necessary to use them, "slow release"nitrogen fertilizers should be used on the lawns and/or landscaping to reduce nitrate loading from these areas. 11