Mr. Tom McCraw September 22, 1976 Page 6. The proper use of "Acceptance Sampling" requires that samples be collected at random within homogeneous areas (see, e.g., SamplingInspection ( H. A. Freeman, M. Friedman, F. Mosteller, and W. A. Wallis, eds.), Mc-Graw Hill, 1948, pages 48, 49 and 89). Concerning the homogeneity assumption, it seems advisable to divide an island into two, three, or more areas depending on general level of activity and to go through the acceptance sampling procedure in each area separately. These areas could be defined on the basis of the plutonium concentrations obtained by the 1972 survey. The assumption of random sampling within areas is important in order to preserve the a and 8 risks decided on for the decision making process. The use of alternative sampling plans, such as sampling at grid nodes of a systematic grid, must be carefully evaluated and supervised to insure the integrity of the final decision. This is a most important consideration in the design of the cleanup study that requires attention to detail. Some- one familiar with the statistical requirements should be in the field during the sampling process to insure fidelity to the agreed upon design. Wenote that attribute sampling is ordinarily used in situations where the "attribute" can be measured accurately for each element examined and decisions about a given population (often a quantity of manufactured product) are to be made on the basis of the sampled elements. Hence we are neglecting "counter error" here and assuming decisions are to be made on the basis of whether or not sample elements from a given area (e.g., soil aliquots) indicate that a proportion of such elements are above some set limit. Question 4: For certification of islands for which cleanup of Pu has been performed: a) b) c) What data are required? How are the data to be evaluated? What goals that are likely to be attainable in terms of the assurance that can be given that the cleanup criteria have been met? , In Question 3 we suggested acceptance sampling as a method to decide whether cleanup is necessary. Following the cleanup operation additional soil samples and In-Situ measurements must be taken for certification. Acceptance sampling as outlined above could also be used for this purpose (see TABLE 1 for number of samples required). If the certification requirement states that all collected samples must have plutonium concentrations below the critical level L, then the values of n in TABLE 2 below are appropriate (calculated using Table 12 in Burstein). If any sample has activity greater than L then the cleanup operation has not been successful and certification would not be issued. 8B and ps are defined as above in our discussion of Question 3. Note that the a risk (of concluding that cleanup is necessary when it really isn’t) is not specified in TABLE 2. This risk does exist, but is ignored here on the basis that risk 8 (of concluding that further cleanup