Page 413 - Soil and water contamination, 2nd edition

400 Soil and Water Contamination

d. 3.52 mg l -1
e. Pe = 100; transport is dominated by advection;
f. The dispersion coefficient is about 2 orders of magnitude greater than molecular
diffusion coefficient, which implies that the contribution of molecular diffusion to
mixing (and transport) is negligible.

7. 132 m.

9. a. Approximately 0.05
b. Approximately 0.4 (drainage line).
c. Approximately 0.11
d. Because NAPL remains behind in the soil pores (insular saturation)
e. 1.515 m 3

CHAPTER 12

1. a. 0.98 N m -2
b. Neither erosion nor deposition.

3. 0.075 N m -2

4. a. 189 kg
b. The sediment in the water column will become depleted and will settle almost
entirely. The concentration of suspended solids in the water column will become
almost zero and sedimentation will cease.

7. a.
Section Slope length Interrill erosion rate Rill erosion rate Transport capacity
(m) (kg m y ) (kg m y ) (kg m y )
-2
-1
-1
-1
-2
-1
1 50 0.135 0.099 11.8
2 100 0.234 0.451 54.1
3 150 0.090 0.107 12.9
b.
Section Total erosion Cumulative total erosion Transport capacity
-1
-1
-1
-1
-2
(kg m y ) (kg m y ) (kg m y )
-1
1 0.0052 l 0.75 + 0.135 0.0030 l 1.75 + 0.135 l 0.63 l 0.75
2 0.0143 l 0.75 + 0.234 0.0082 (l – 50) 1.75 + 0.234 (l – 50) + 9.6 1.71 l 0.75
3 0.0025 l 0.75 + 0.090 0.0014 (l – 100) 1.75 + 0.090 (l – 100) + 0.30 l 0.75
29.0

10/1/2013 6:47:53 PM
Soil and Water.indd 412
Soil and Water.indd 412 10/1/2013 6:47:53 PM