Meetings have been held over the past six months relative to the selection of nuclear sites for intensive study. areas are under analysis. Preliminary samples from the nonclassified AREAS OF CONCERN AND RECOMMENDATIONS The LASL soil study personnel have reviewed past and recent activities as they relate to initial assignment. A primary purpose for the review has been to indicate major problems which require further study. By way of summary, recognized gaps in our knowledge are presented as questions, answers, and recommendations from the LASL soil studies personnel and other NAEG principal investigators who have indicated to us related problems. Sampling For the soil types sampled, data indicate that if cross contamination has occurred, it has not contributed significantly to the results presented. For the types of soil sampled, the two methods presented, surface and profile sampling, have been successfully used for the safety shot site soils. For stony or rock soils as will be encountered in the nuclear sites, for sampling into highly cemented soil horizons, or for special matrices such as asphalt, concrete, steel, or wood, the LASL soil study personnel recommend development and testing of special sampling techniques. Groundwater, mucks, and sludges will present problems, particularly if profile samples are to be required. Testing procedures should consist of (1) determination of physical uniformity of samples collected, (2) measurement of degree of cross contamination due to sampling, and (3) comparison of methods statistically. Analytical Methods for Radionuclides of Interest Of certain radioisotopes listed in the original charter, the major effort has been placed on plutonium, americium, and uranium. As related to the original charge, are the analytical methods now in use or available adequate for the determination of low levels of activity of future radionuclides of interest? The methods for plutonium analysis used to date have proved adequate on standard samples; however, comparison of samples is difficult where the "hot particle problem" exists. A concentrated effort should be expended on testing of present radiochemical procedures for low levels of 24lan, especially where plutonium to americium ratios are of interest. The work on such methods now in progress could serve as a useful base. Quality Assurance The LASL soil study personnel view quality assurance as a most essential part of any sampling and analysis program. A question is posed as to the adequacy of the present quality assurance program. 31