Re: Background radiation, Geiger counters, and health effects

[BLHamrick@AOL.COM]

In a message dated 6/5/2003 1:15:56 PM Pacific Standard Time, lists@richardhess.com writes:


> Isn't it a trivial matter to measure radiation in many areas--walk around 
>
> with a Geiger counter in the simplest form--and compare this to background?



Oh, if only it were trivial.  The problem is that one can walk around with a survey meter, and find background ranging from 5 microR per hour to 10 microR per hour within a few feet, depending on the geology of the area (and much more dramatic variations can be found in many areas).  This additional 5 microR per hour, theoretically, presents an additional 5 x 8760 hours per year = 43 millirem per year, or almost half the public dose limit from licensed operations, and almost twice the dose limit from terminated operations.  Is it from "natural" sources?  Or from "man-made" sources?  It is very expensive to find this out, particularly when one is talking about a potentially residually-contaminated site that may cover several hundred acres.


And, we haven't even gotten to the tricky part - i.e., the other pathways.  External radiation is only one component of potential exposure from a "contaminated" site - there may be dose from the migration of contamination to groundwater that ultimately contributes to a drinking water supply, or from the uptake of soil contamination in local vegetation eaten by humans, or by the animals that humans ultimately eat, or there may be resuspension of surface contamination (i.e., kicking up dust) creating an inhalation pathway, and, of course, there is always Justice Breyer's favorite pathway - the dirt-eating children.  Assessing the transfer of contamination through these pathways is an extremely expensive proposition, even with the assistance of the dose-modeling software that exists.


This is why the question of whether the LNT is truly the "conservative" assumption should be re-evaluated.  The public needs to understand the real costs of assessing, let alone remediating, contamination that could theoretically produce doses in the range of background, and in the range of the natural variation of background, but yet are above the "legal" limits.


If it were as simple as going out and swinging a meter through someone's home to satisfy their fears, I think most HPs I know would be more than happy to devote some time to this, but the problem is not at all that simple. 


Barbara