Deep Creek Lake study

One of the most important projects in progress in the field of hybrid receptor modeling is the Allegheny Mountain study by Pierson et al. of Ford Motor Co. (This Volume). Concentrations of many ions, major, minor and trace elements in airborne particles, rain, dew and fog and other parameters were measured at Allegheny Mt., PA and Laurel Hill, 35 km to the northwest, from 5 to 28 Aug 1983, approximately simultaneously with the Deep Creek Lake studies discussed above. These two huge data sets are now nearly complete and ready for detailed interpretations by the participants and other researchers in the field. In particular, Keeler is working with the Ford group to apply the Samson method to the data. 

We have used both the horizontally and vertically configured impactors to sample coal-combustion aerosols in elevated plumes and in plumes at ground level near Deep Creek Lake in western Maryland. Few problems were encountered in this study however, particle bounce could not be evaluated for ambient samples because the individual submicrometer particles could not be discerned. Marple and Rubow (8) have performed extensive calibrations with monodisperse aerosols these show that impaction plates covered with aluminium foil have slightly larger D50S than plates covered with Teflon-fiber filters. 

In my view, hybrid receptor models are the most likely approach for provide reasonable answers to the sulfate deposition problem within a time that they might be of use in influencing controls that may be imposed on S02 and NO sources. This does not mean that there is no need for further field studies. The Allegheny Mt. and Deep Creek Lake data sets were taken so close together that one would feel much safer if similar data were available at several other sites, e.g., the three sites of the Ohio River Valley study (20) and one or two sites to the northeast of Allegheny Mt.,... 

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