Numerical Evaluation and Management Suggestions for Heavy Metal Pollution Risks in a Sludge Landfill: A Case Study from Fuyong Landfill, Shenzhen, China

Table 2

Parameters of the calculation model.

Parameters		Solidified sludge	Natural silt	Sand	Silty clay
Hydraulic conductivity (m/s)		1.0 × 10^−7	1.0 × 10^−8	1.850 × 10^−5	1.1 × 10^−8
Porosity (%)		50.0	60.0	33.0	53.0
VG–Parameters
a (m^−1)		1.0	1.0	5.75	1.0
n (–)		1.2	1.2	1.6	1.2
θs (–)		0.541	0.541	0.541	0.541
θr (–)		0.2	0.2	0.0	0.2
Longitudinal dispersivity (m)		0.1	0.1	1.0	0.1
Diffusion coefficient (×10^−10 m^2/s)
Cd		8.90	8.90	8.90	8.90
Cu		7.90	7.90	7.90	7.90
Ni		0.59	0.59	0.59	0.59
Pb		3.60	3.60	3.60	3.60
Zn		3.30	3.30	3.30	3.30
Retardation factor (–)
Cd		2.0	2.0	1.0	2.0
Cu		3.3	3.3	1.0	3.3
Ni		2.0	2.0	1.0	2.0
Pb		30.0	30.0	1.0	30.0
Zn		3.0	3.0	1.0	3.0