Great Lakes rates

Wang, L.K. and Wang, M.H.S., Decontamination of groundwater and hazardous industrial effluents by high-rate air flotation process, Proc. Great Lakes 1990 Conference, Hazardous Materials Control Research Institute, Silver Springs, MD, September 1990. 

Volatilization. Transfer of chemicals across the air/water interface can result in either a net gain or loss of chemical, although in many cases the bulk concentration in the air above a contaminated water body is low enough to be neglected (20). When the atmosphere is the primary source of the contaminant, as for example polychlorinated biphenyls in some parts of the Laurentian Great Lakes, atmospheric concentrations obviously cannot be neglected. The Whitman two-film or two-resistance approach (21) has been applied to a number of environmental situations (20, 22, 23). Transport across the air/water interface is viewed as a two-stage process, in which both phases of the interface can offer resistance to transport of the chemical. The rate of transfer depends on turbulence in the water body and in the atmosphere, the... 

Transfer rate constants are postulated as shown in Table II, following the approach described by Mackay and Paterson (4). The air-water value selected was lower than is generally used since it appears that a low value is necessary to reconcile observed air and water concentration, and mass balances as discussed in a recent review of PCB behavior in the Great Lakes (Mackay et al. U3)). 

Eventually, atmospheric arsenic falls on the Earth s surface through wet and dry deposition. Sweet, Weiss and Vermette (1998) evaluated the deposition of arsenic over lakes Erie, Michigan, and Superior in the Great Lakes of North America. Overall, the wet and dry deposition rates for the lakes were very similar. Specifically, they were 72-94 and 66-91 pgm 2year 1, respectively. 

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