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Nitrification of the average Total Nitrogen(TN).concentration of 87 mg/L, as determined below in <br /> Section IV would require: 87 mg/L NH4-N x 7.1 mg CaCO3 =618 mg/L alkalinity. Therefore the <br /> alkalinity in the domestic water supply is deficient if the TN will be equal to 87 ppm, and <br /> nitrification may be inhibited. <br /> Mounding Analysis <br /> Reference is made to the encountered groundwater table at 10 feet below existing grade. This <br /> shallow groundwater table may induce a phenomenon known as the mounding effect. A procedure <br /> developed by Finnemore and Hantzsche (1983) is used below to predict the long-term maximum <br /> rise of the mound: <br /> h =H +Zm = 2 <br /> where: h =distance from boundary to mid-point of the long-term mound, in ft <br /> H =height of stable groundwater table above impermeable boundary, in ft <br /> Zm = Iong-term maximum rise of the mound, in ft <br /> Substituting known and estimated values for the variables, we find the following: <br /> H=From the attached well log for the adjacent well, a clay layer exists from 14 ft to 22 ft below <br /> grade. Therefore, since the water table is at 9 ft, and using 14 ft as the boundary, H = 5 ft. Long- <br /> term maximum rise is estimated at 4. Therefore, h= 5 + 4-2 = 7 <br /> Zm = <br /> 1 C14 )n �K_l <br /> J0.5n �t )1-0.5n <br /> where: Q= average daily flow in ft'/ day <br /> A= area of disposal field in ft2 <br /> C =mounding equation constant <br /> L=length of disposal field in ft <br /> K=horizontal permeability of soil in ft/day <br /> n =mounding equation exponent <br /> Sy= specific yield of receiving soil in percent <br /> t =time since the beginning of wastewater application in days <br /> Substituting known constants for the variables, we find the following: <br /> Q = 1050 gpd(From Max. flow volume calcs.,Page 9)- 7.48 gals/ft3 = 140.4 ft3/day <br /> A =2,200 ft2(From filter bed sizing calcs.,Page 14) <br /> C =Length to width ratio z 1, therefore, C = 3.4179 <br /> L= 53 ft <br /> K=Using vertical permeability as most conservative= 31 min/in = 1440 min/day- 31 = 3.9 ft/day <br /> h = 7 (See above) <br /> n =Length to width ratio =1, therefore, n = 1.7193 <br /> Sy= 27% <br /> t = 3,650 days (10 yrs) <br /> Z. =0.218x85.0x0.05822x1.669 = 1.8ft <br /> 6 <br /> Chesney Consulting <br />