Ventilation pollution transport

When widespread stagnation suppresses convective transport out of the basin, the accumulation of pollutants may proceed. The buildup of atmospheric constituents will be governed by (a) primary emissions (b) in situ transformations (production or loss terms) (c) intrabasin circulation (d) ventilation and (e) removal by... 

Transport and Transformation. Once emitted into the atmosphere, the fate of a particular pollutant depends upon the stability of the atmosphere, which determines the concentration of the species, the stability of the pollutant in the atmosphere, which determines the persistence of the substance. Transport depends upon the stability of the atmosphere which, in turn, depends upon the ventilation. The stability of a pollutant depends on the presence or absence of clouds, fog, or precipitation the pollutant s solubility in water and reactivity with other atmospheric constituents (which may be a function of temperature) the concentrations of other atmospheric constituents the pollutant s stability in the presence of sunlight and the deposition velocity of the pollutant. 

Net uptake of heavy metals is due to the removal of heavy metals in crops or trees in the catchment and/or in aquatic plants and fish in lake. Weathering relates to the release of HM from primary minerals in the catchment. Sedimentation is the result of the setting of suspended particles in the lake. As a result of this process, the pollutant absorbed to the suspended particles is transported from the water compartment to the sediment compartment. Resuspension of sediment particles is the result of the turbulence at water-sediment interface. As a result of this process, the pollutant absorbed to the sediment particles is transported from the sediment compartment to the water compartment. The exchange processes at the sediment water interface include advection or infiltration, molecular diffusion, and bioturbation and bioirrigation (the latter are the transport of HM resulting from the ventilation of tubes and burrows in the sediments by benthic organisms). To scale these processes to the catchment, the sedimentation and resuspension rates are multiplied by the ratio of the lake area and the catchment (de Vries et al, 1998). 

Next to the legislation on OELs and BATs, the requirements of the Ordinance on Hazardous Substances apply as well as various other regulations at national level dealing with flammable liquids, water pollution, air pollution,major hazards,storage and transport, protective equipment and ventilation. 

---