Mobile, Immobile, and Multiflow Domain Approaches - Transport and Fate of Chemicals in Soils: Principles and Applications - page 295

0.05

Cecil I-Small pulse predictions

(a)

0.04

v = 2.23 cm hr -1

0.03

Exp. data
One domain
Two domain

0.02

0.01

0.00 0

1 2 3 4

0.05

Cecil II-Small pulse predictions

(b)

0.04

v = 5.21 cm hr -1

0.03

Exp. data
One domain
Two domain

0.02

0.01

0.00

0 1 2 3 4

0.05

Cecil III-Small pulse predictions

(c)

0.04

v = 2.28 cm hr -1

0.03

Exp. data
One domain
Two domain

0.02

0.01

0.00

0 1 2 3 4

Pore Volume (V/V o )

FIGURE 8.23
Tritium breakthrough curves (BTCs) for three Cecil soil columns under different fluxes. The
applied tritium pulse was 0.02 pore volume. Solid and dashed curves are fitted BTCs with the
one- and two-flow domain models, respectively.

shape of the BTC depended on pulse duration and flow velocity. Those col-
umns that received a small tritium pulse also showed early breakthrough,
with the first peak position well within one pore volume. Similar BTC
results were obtained for Cecil and Dothan soils, as shown in Figures 8.23
and 8.24, respectively.