Nomenclature
δi	Stoichiometric mass of oxygen consumed per mass of hydrocarbon	g/g
Δp	Pressure difference between the soil and the building	Pa
θt	Total porosity of the soil	m3/m3
θw	Water-filled porosity of the soil	m3/m3
λi	Biodegradation rate of hydrocarbon in water phase	Hr−1
μ	Vapor viscosity	g/(m – hr)
η	Foundation cracks area fraction	m2 cracks/m2 tot
Ab	Foundation footprint area	m2
ci	Concentration of hydrocarbon in the soil-gas phase	g/m3
$c_i^{\mathit{\text{indoor}}}$	Concentration of hydrocarbon in indoor air	g/m3
$c_i^s$	Concentration of hydrocarbon at vapor source	g/m3
co	Concentration of oxygen in the soil-gas phase	g/m3
$c_o^{\mathit{\text{atm}}}$	Oxygen concentration in the atmosphere	g/m3
$c_o^{\mathit{min}}$	Minimum oxygen concentration to sustain biodegradation	g/m3
df	Depth of the building foundation slab below ground surface	m
ds	Depth of contaminant source below ground surface	m
Di	Effective porous medium diffusion coefficient of hydrocarbon	m2/hr
D0	Effective porous medium diffusion coefficient of oxygen	m2/hr
ER	Building air exchange rate	hr–1
kν	Soil permeability to vapor flow	m2
Hi	Henry's law constant for hydrocarbon	dimensionless
L	Vertical distance from source to the the bottom of the foundation	m
La	Thickness of the aerobic zone in the subsurface	m
Lb	Thickness of the anaerobic zone in the subsurface	m
Lcrack	Thickness of the building foundation slab	m
Lmix	Enclosed space volume/infiltration area ratio	m
Lslab	Width of the building slab (foundation)	m
W	Dimensionless oxygen or hydrocarbon concentration	dimensionless
Wa	Dimensionless oxygen or hydrocarbon variable at the interface	dimensionless
x	Coordinate in the horizontal direction	m
Xcrack	Perimeter of the building foundation	m
xck	Distance of the slab entry cracks from the building center	m
Z	Coordinate in the vertical direction	m