Re: airborne releases from area sources

[GACMail98@aol.com]

In general, if the distance from the source is much greater than the
characteristic length of the source, then it is okay to treat it as a point
source.

E.g., if the area source is a circle with diameter of, say, 10 ft, then the
effect of airborne releases at, say, 1000 ft away would be equivalent to a
point source with same strength located at the center of area source.  

On the other hand, for the same 10 ft diameter area source, you might not want
to assume a point source for impacts at, say, 20 - 50 ft away.

But, here's another question, which is more conservative (i.e., which results
in greater impact) - assuming a point source or an area source?

Good luck.

Glenn
GACMail98@aol.com

In a message dated 98-10-02 15:01:50 EDT, WMCCABE@tnrcc.state.tx.us (William
McCabe) writes:

<< Does anybody have any information or references regarding at what
 distance from an area source (e.g., acres of contaminated ground
 surface) could one treat calculation of airborne releases as if they were
 coming from a point source?   Would such a calculation be proper or
 appropriate?  Any help or information would be appreciated. >>
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