According to the given data, log(Koc) = 2.1 mL/g.
Thus, Koc = 125.9 mL/g
a) The distribution coefficient, Kd = foc *
Koc = 0.017 * 125.9 mL/g = 2.14 mL/g
b) Bulk density of the aquifer material, b =
s(1-n) ;
where s: particle density
and n: porosity
= 2.6 * (1-0.3) = 1.82 g/cm3
c) Retardation factor, R = 1 + (b /n)(Kd) = 1 + (1.82/0.3)(2.14) = 13.98
d) Darcy's velocity, VD = K (Difference in hydraulic
head between two lateral points / Length between two lateral
points)
= 2.5 x 10-3 x (0.01/2) cm/sec = 1.25 x 10-5
cm/sec = 1.25 x 24 x 3600 x 10-5 cm/day = 1.08
cm/day
Groundwater flow velocity = VD/n = 1.08/0.3 = 3.6
cm/day
e) Time needed = 2 / (3.6 x 10-2 ) = 55.55 days = 0.152
year
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