Summary of attenuation-removal mechanisms for primary pollutants found in stormwater runoff.
Link to this table

Mechanism Pollutants affected Promoted by
Sedimentation
Filtration
Soil incorporation
Precipitation
Sorption - adsorption
Sorption - ion exchange
Oxidation
Degradation - photolysis
Degradation - volatilization
Degradation - biological
Plant metabolism
Pathogen die off
Nitrification
Denitrification