Hydrogeology. Kevin M. Hiscock

product molⁿ L⁻ⁿ J joule (energy, quantity of heat) K equilibrium constant molⁿ L⁻ⁿ K (hydraulics) hydraulic conductivity m s⁻¹ K (temperature) kelvin K _d partition or distribution coefficient mL g⁻¹ K _f fracture hydraulic conductivity m s⁻¹ K _H Henry’s law constant Pa m³ mol⁻¹ K _oc organic carbon‐water partition coefficient K _ow octanol‐water partition coefficient K _s selectivity coefficient K _sp solubility product molⁿ L⁻ⁿ k _i intrinsic permeability m² L litre (volume) LNAPL light, non‐aqueous phase liquid l length m MNA monitored natural attenuation m mass kg mol amount of substance (see Box 4.1) n an integer n roughness coefficient (Manning’s n) n porosity n _e effective porosity P Peclet number P precipitation amount mm P pressure Pa (or N m⁻²) P partial pressure atm or Pa P _A′ P_o atmospheric pressure atm or Pa Pa pascal (pressure) P _w porewater pressure Pa or m of water PAH polycyclic aromatic hydrocarbon PDB Pee Dee Belemnite PE potential evapotranspiration mm p −log₁₀ ppm parts per million Q discharge m³ s⁻¹ Q _f fracture flow discharge m³ s⁻¹ q specific discharge or darcy velocity m s⁻¹ R hydraulic radius m R (R_d) recharge (direct recharge) mm a⁻¹ R universal gas constant (8.314 J mol⁻¹ K⁻¹) RC root constant mm R _d retardation factor R _e Reynolds number rem roentgen equivalent man (older unit of dose equivalent; 1 rem = 0.01 Sv) S entropy J mol⁻¹ K⁻¹ S sorptivity of soil cm (min)^−1/2 S storativity S slope S _p specific retention S _s specific storage s⁻¹ S _sp specific surface area m⁻¹ S _y specific yield