R2 Coefficient of determination () Se Effective soil saturation () T Time (d) v Porewater velocity, also referred to as tracer velocity (m/s) X Transport distance (m) z Depth (m) α, n, m shape parameters of the van Genuchten model (1/m, , ) α Dispersivity (m) αL Longitudinal dispersivity parameter (m) αTH Horizontal transverse dispersivity (m) αTV Vertical transverse dispersivity (m) Δz Depth increment (m) ƞ Total porosity (cm3/cm3) ƞe Effective porosity (cm3/cm3) θ Volumetric soil water content (cm3/cm3) θ(h) Soil moisture characteristic, also referred to as soil water retention curve (cm3/cm3) θr, θs Residual and saturated soil water content respectively (cm3/cm3)
Flatbed trucks loaded with containers (HF) ~ 1 m2 5 gallon (i.e. 19 L) sealed buckets Instantaneous Various See NICNAS (2017c) Tanker truck (HF) ~ 10 m2 Contents of the tanker truck (e.g. 4 000 gallons; ~15 000 L) Instantaneous e.g. Hydrochloric acid See NICNAS Line sources Leaking pipes of coproduced water transported to water treatment facility Few 100s of m2 (based on a 1×100 m contaminated area) Several m3 Instantaneous and longterm (if not immediately detected) Various See Mallants et (2017a) Uncertain; to typical concentrations in produced water See Mallants et al. Leaking hoses from blender truck to well (fracturing) Few 10s of m2 (based on a 1×10 m2 contaminated area) Several m3 Instantaneous Various See Mallants et (2017a) Uncertain See Mallants et al. Area sources Dust control Up to 1 ha 10 000 L/day/ha or 103 m/m2/day Up to one year Depending on groundwater and degree of interaction with HF fluid Uncertain; refer to typical concentrations in flowback water as a guide See NICNAS (2017c) Storage for flowback and coproduced water Various sizes (e.g. 1600 m2 and larger) Normal operations with different liner designs: expected leakage rate either 0.35, 3.5 or 35 mm/year Accidental conditions (e.g. flooding): several orders of magnitude higher Improper Longterm (years) Depending on groundwater and degree of interaction with HF fluids Uncertain; to typical concentrations in produced water as a guide See Mallants et al. (2017a) y
Figure B 11 Solute after 1 500 years following a 30-year release from a leaking storage pond. Reference aquifer hydraulic conductivity, reference river bed conductance, and decreased porosity. A unit input concentration at the soil-groundwater interface is assumed (i.e. C0 = 1 M/L3, where M/L3 is a user defined unit) Figure B 12 Solute plume after 1 500 years following a 30-year release from a leaking storage pond. Reference aquifer hydraulic conductivity, reference river bed conductance, and increased porosity. A unit input concentration at the soil-groundwater interface is assumed (i.e. C0 = 1 M/L3, where M/L3 is a user defined unit) Figure B 13 Solute plume after 1 500 years following a 30-year release from a leaking storage pond. Reference aquifer hydraulic conductivity, increased river bed conductance, and decreased porosity. A unit input concentration at the soil-groundwater interface is assumed (i.e. C0 = 1 M/L3, where M/L3 is a user defined unit) Figure B 14 Solute plume after 1 500 years following a 30-year release from a leaking storage pond. Reference aquifer hydraulic conductivity, increased river bed conductance, and reference porosity. A unit input concentration at the soil-groundwater interface is assumed (i.e. C0 = 1 M/L3, where M/L3 is a user defined unit) Figure B 15 Solute plume after 1 500 years following a 30-year release from a leaking storage pond. Reference aquifer hydraulic conductivity, increased river bed conductance, and increased porosity. A unit input concentration at the soil-groundwater interface is assumed (i.e. C0 = 1 M/L3, where M/L3 is a user defined unit) Figure B 16 Solute plume after 1 500 years following a 30-year release from a leaking storage pond. Increased aquifer hydraulic conductivity, decreased river bed conductance, and decreased porosity. A unit input concentration at the soil-groundwater interface is assumed (i.e. C0 = 1 M/L3, where M/L3 is a user defined unit)