Parameters for determining pesticide concentration in groundwater

**INPUT PARAMETERS**

**A**

surface area of building(s) with leaking tanks inside (m^{2})

**D**

thickness of aquifer (m)

**I**

hydraulic gradient of the groundwater (dimensionless)

**K**

hydraulic conductivity of the aquifer (m/day)

**log K _{OC}**

partitioning coefficient between water and organic carbon

**M**

amount of pesticide leaked from tanks (kg)

**R**

annual rainfall (m/year)

**Q**

discharge of well, spring or river (m^{3}/year)

**S**

water solubility of the pesticide (kg/m^{3})

**T**

time since tanks started leaking (years)

**V**

water volume of lake, reservoir or pond (m^{3})

**x**

measured distance from storage facility to vulnerable object (m)

**OUTPUT PARAMETERS**

**a**

constant (dimensionless)

**C _{0}**

concentration in soil moisture at storage facility (kg/m^{3})

**C _{l}**

concentration in groundwater at storage facility (kg/m^{3})

**C _{g}**

concentration in well, spring or river (kg/m^{3})

**C _{s}**

concentration in lake, reservoir or pond (kg/m^{3})

**d**
relative distance from store to vulnerable object (dimensionless)

**f _{g}**

dispersion factor for groundwater (dimensionless)

**f _{s}**

dispersion factor for surface water (dimensionless)

**L**

annual load of pesticide (kg/year)

**mg**

mixing factor for groundwater (dimensionless)

**ms**

mixing factor for surface water (dimensionless)

**q**

specific groundwater discharge (m/year)

**r**

retardation factor (dimensionless)

**s**

horizontal distance travelled by the centre of mass of the dispersion front (m)

**Be sure to use the correct dimensions!**