-4- where it was suspected that contamination may be buried. those data are probably not representative Ms. Barnes has agreed to pull Hence, of undisturbed areas. the 10 and 20 cm data together and transmit to me, hopefully in time for our June 5-6 meeting in Livermore. These data, although tainted by the possibility of cross contamination from the soil surface, may be useful for LLL’s dose assessment model. (9) The length of rope used to measure distance from the center of the IMP reading circle to soil sample locations was found to be 1 meter too short. The exact date when this change was made is unknown, but it was expressed at the meeting that the rope should have been at the correct length for the following Vera, Olive and Aoman. islands: Janet, Lujor, Irene, The other islands are open to question. The extent of any bias in the soil-IMP regressions is unknown. Since the rope error would place soil samples closer to the center of the circle than intended, the IMP values may be low relative to soil 241Am. A related problem is that the arrangement and location of soil samples within the IMP sight radius was designed by M. Barnes using incorrect IMP calibration indicated information. to me that two of the inner ring soil samples should have been taken in the outer ring to correspond what the IMP “sees.” length is apparently more closely with The net effect on the IMP and soil Am comparisons due to this misplacement (10) Ms. Barnes of soil samples and the incorrect rope unknown. Different detectors have been used on IMP’s at different t roes. Two detectors had low efficiencies. These are being corrected but it is not known (by John Tipton) whether these detectors were actually i used and if so, whether the IMP data were corrected. Following lunch, John Tipton, Al Doles and Madaline summarize or express any areas of particular concern. confidence quite well. John Tipton expressed in the IMP system and felt that, on the whole, Al Doles i Barnes were asked to it was performing (Eberline) expressed the need to do IMP field calibration studies, and more quality control soil samples (blind spikes) prepared by an