Table 2:

Retardation factors for the Accusand for the simulations that have included air-water interfacial adsorption. The retardation factors are average values in the vadose zone over the entire simulation time; each $\overline{R}$ and the fractions contributed by air-water interfacial adsorption (${\overline{f}}_{\text{awia}}$) and solid-phase adsorption (${\overline{f}}_{\text{spa}}$) correspond to one simulation. The corresponding average values of water content, air-water interfacial area, and air-water interfacial adsorption coefficient are also presented.

Climates	PFOS (mg/L)	$\overline{\theta }$ (−)	${\overline{A}}_{aw}$ (cm2/cm3)	${\overline{K}}_{aw}$ (cm3/cm2)	$\overline{R}$ (−)	${\overline{f}}_{\text{awia}}$ (%)	${\overline{f}}_{\text{spa}}$ (%)
Semi-arid	100 1000	0.039 0.037	505.0 510.1	0.0652 0.0069	1355 233	99.1 97.3	0.9 2.7
Humid	100 1000	0.048 0.046	472.3 476.3	0.0647 0.0151	1101 326	99.1 98.3	0.9 1.7