## Appendix F. LIST OF SYMBOLSDimensions (M, mass; L, distance; T, time) are given in brackets. *A*is cross-sectional aquifer area perpendicular to the groundwater flow direction [_{aq}*L*^{2}].*A*is cross-sectional area perpendicular to the vertical infiltration in the soil column [_{soil}*L*^{2}].*B*is aquifer thickness [*ft*].*c*is residual between two successive Gauss-Sedial iterations.*C*_{0}is liquid phase solute concentration in the infiltration water [*mg/L*].*C*is concentration of horizontal groundwater influx [_{aq}*mg/L*].*C*is concentration of a contaminant in liquid (water) phase [_{w}*mg/L*].*C*is concentration of a contaminant in vapor (air) phase [_{a}*mg/L*].*C*_{mx}_{(i)}is mixed concentration in groundwater [*W/V*].*C*is concentration of a contaminant in solid phase [_{s}*mg/Kg*].*C*(_{s}*z*,0) is initial solid-phase concentration [*mg/Kg*].*D*is combined dispersion coefficient.*D*is gaseous phase diffusion coefficient in the pore air [_{a}*ft*^{2}/*yr*].*D*is diffusion coefficient of the contaminant in the free air [_{air}*ft*^{2}/*yr*].*D*is dispersion coefficient for the liquid phase contaminant in the pore water [_{w}*ft*^{2}/*yr*].*f*is fraction organic carbon of the soil [_{oc}*g/g*].*K*is distribution coefficient between the solid phase and liquid phase [_{d}*ml/g*].*K*is dimensional form of Henry's Law constant [_{H}*atm-m*3/*mol*].*K*is organic carbon-water partition coefficient [_{oc}*ml/g*].*h*is head potential [*L*].*H*is Henry's partition coefficient between the air phase and water phase [dimensionless].*H*is penetration depth [_{d}*ft*]._{di}is adjusted penetration depth for each column [*L*].*h*is value of the head at the lattice point at (_{i,j}*I,j*)[*L*].*i*is discretized soil column cell (column index in finite difference grid).*j*is row index in finite difference grid.*k*is time level.*K*is hydraulic conductivity [*L/T*].*L*is horizontal length dimension of the waste [*ft*].*L*is vertical distance from the source to the observation point (_{u}*i.e.*, the water table) [*L*].*m*is iteration index.*M*is total contaminant mass per unit volume of the soil.*n*is total porosity of the soil: equals the sum of water filled porosity and air filled porosity.*N*is head to a reasonable number of points.*q*is air flow velocity [_{a}*ft/yr*].*q*is the Darcy velocity in the aquifer [_{aq}*ft/yr*].*q*is specific flow rate in x direction [_{x}*L/T*].*q*is specific flow rate in y direction [_{y}*L/T*].*q*is water flow velocity (recharge rate) [_{w}*ft/yr*].*R*is universal gas constant (*R*= 8.2�10^{-5}*atm-m*^{3}/*mol�K*).*t*is time [*yr*].*T*is absolute temperature (�*K*= 273.16 + �*C*).*t*_{0}is duration of solute release [*yr*].*V*is flow function.*z*is vertical coordinate with positive being downward.*a*is longitudinal dispersivity of the vadose zone [_{L}*ft*].*a*is transverse (vertical) dispersivity of the aquifer [_{v}*ft*].*Dt*is time increment.*Dx*is distance of lattice point in horizontal space [*L*].*Dy*is distance of lattice point in vertical space [*L*].*g*is decay rate of the solute source due to either degradation or flushing by the infiltration [1*/yr*].*m*is first order decay rate of a contaminant : in this model, for simplicity, it is assumed that*m*=_{w}*m*_{a}=*m*=_{s}*m*.*m*is first order decay rate of a contaminant in water phase [1/_{w}*yr*].*m*_{a}is first order decay rate of a contaminant in gaseous phase [1/*yr*].*m*is first order decay rate of a contaminant in solid phase [1_{s}*/yr*].*v*is seepage velocity.*q*is combined retardation factor.*q*is volumetric water content (volume of water / total volume) [_{w}*ft*^{3}/*ft*^{3}].*q*is air-filled porosity (volume of air / total volume) [_{a}*ft*^{3}/*ft*^{3}].*r*_{b}is bulk density of the soil [*gr/cm*^{3}].
Last modified: Oct 15, 1999 VG Model/ Samuel Lee / VADOSE.NET |