4582 Maryland Parkway WATER RESOURCES CENTER Oi °o Las Vegas, Nevada 89109 (702) 736-2293 Desert Research Institute — University of Nevada System February Dr. Richard 0. 3, 1980 Gilbert Battelle Pacific Nortnwest Laboratory P.O. Box 999 Richland, WA 99352 Dear Dick: In order to give you a better idea of the ranges and distributions of the various kinds of errors that affected the Enewetak data, I am enclosing a short writeup on that subject. I am also enclosing my draft of a proposed Tech Note descriping how we propagated errors during the cleanup. If that sounds familiar, it about two years doing it. ago, it's because you asked me to write and I've just now gotten around to My understanding is that this information on errors will be presented to the Marshall Islands Advisory Group ("Bair Committee") at the same time as John Tipton's new information on the soil mass attenuation coefficient. I believe the idea is to provide a comparison between the bias due to using the wrong attenuation, and the random errors that are present. Please look this material over, and if you have questions or comments, of if you want more information before the committee meets to hear Tipton, call me at (702) 736-2293. Sincerely, Pidir bond. bez TI Ka Madaline Barnes Research Statistician MB: ds Encl. Water Resources Center @ Energy and Atmospheric Environment Center Applied Ecology and Physiology Center « Human Systems Center