chapter 4: temperature inside the landfill

K s
= K e
h = hmaxe
( 1)
* γ θ −
−aθ
* ( θ −θ
ad )
θ =
( θ −θ
s
ad
)
(2-9)
(2-10)
(2-11)
Where K is the hydraulic conductivity, Ks is the saturated hydraulic conductivity, h is the
suction head, hmax is the maximum suction head, a is the fitting parameter, γ is the fitting
parameter, θ* is the normalized moisture content, θ is the moisture content, θs is the saturated
moisture content, and θad is air, dry moisture content.
Using exponential equations gave a highest value of hs at dry conditions (i.e. when θ
equals zero) while at dry conditions, power equations give an infinite value.
Uguccioni and Zeiss (1997) investigated the leachate movement through MSW using two
models; a one-dimensional HELP model and two-domain model PREFLO. It was concluded that
leachate flow in the landfill can be effectively modeled by a two-domain model which can
simulate channel as well as matrix flow or by a one-domain approach which allows strongly
varying flow parameters like hydraulic conductivity and effective storage.
McCreanor and Reinhart (1999) modeled leachate recirculation in the landfills using
SUTRA which is based on the method of two-dimensional hybrid finite element and integrated
finite difference. It was suggested in the study that heterogeneities in the waste lead to non-
uniform wetting of the waste and homogenizing the waste mass would enhance uniform wetting.
11