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Z_ PAI (4) (Kh 10.5n I Sy)I-0Sn where::Q=average daily flow in ft3/day A=area of disposal field in ft C=mounding equation constant L=length of disposal field in ft K=horizontal permeability of soil in ft/day n=mounding equation exponent Sy=specific yield of receiving soil in percent t =time since the beginning of wastewater application in days Substituting known constants for the variables, we find the following: Q =2,400 gpd(From Max.flow volume calcs)=7.48 gals/fl?=321 ft/day A = 15,050 ftz(From mound system sizing calcs) C=Length to width ratio= 3 therefore,C= 1.61 L=215ft K=Using average vertical permeability as most conservative=5 ft/day h= 1.25(See above) n=Length to width ratio =3,therefore,n= 1.7634 Sy=3% t =3,650 days(10 yrs) Zm =0.0343 x 54 x 0.199 x 2.34=0.86 ft It appears that the maximum mound height that may occur under mound system is 0.86 ft. Since the effluent must travel 1.5 ft through the sand fill of the mound,a distance will exist of approximately 5.6 ft between the sand/effluent interface and the top of the theoretical rise of the mound above the elevation of the water table(5 ft water table minus 0.86 ft=4.14 ft+ 1.5 sand fill distance=5.6 ft). For wastewater treatment to occur, the distance effluent should travel under unsaturated conditions through the soil environment is generally regarded to be 5 ft. In the Finnemore and Hantzsche paper,they discuss three options to consider as potential methods of reducing the mounding phenomenon. The first is increasing the size of the disposal field. Based upon the average daily flow calculations,the disposal area is ample size to accommodate the projected flow volumes post Sikh Temple expansion. The second method is elongating the shape of the area perpendicular to the groundwater flow. As noted on the design plans,the mound system is elongated in a 3:1 length-to-width ratio,which is regarded as sufficient. Thirdly,operating the field intermittently should decrease the mounding effect. As noted in this Report,effluent will be pumped by four alternating pumps in a dose chamber that will alternate/circulate timed doses of approximately 75 gallons per dose. E. SURFACE WATER INFORMATION Storm water management is currently managed by an on-site retention basin located in the northeast comer of the property. It is proposed to enlarge the basin during expansion improvements. The retention basin is directly down-gradient from the future mound system. Since groundwater typically flows in the direction of j topography,which slopes to the northeast as illustrated on the USGS Map found in Appendix D,ground- water directional flow is northeast. Percolating rainwater from this basin into the top aquifer mixing layer may create a dilution effect to the percolating septic system effluent. According to a scientific paper authored by Shaw and Turyk(1994),reduction of nitrate concentrations in groundwater can occur primarily through dispersion,or by percolating rainwater recharge. 5