standardizing, and distributing the standard samples was assigned to Western Oregon State College (WOSC). In this way the primary responsibility for evaluating the analytical integrity of the data was vested in a disinterested party. In some cases, small variances from these criteria were allowed to facilitate processing the data, but the deviations were never great enough to compromise the integrity of the data. Specifically, the error requirements shown in Table | were relaxed by 20% for some of the early DCDs to accomodate problems some of the contractors had in reducing counting errors. For example, for samples where a 10% relative standard deviation was required, a 12% relative standard deviation was allowed. Another variance was in the number of duplicates and standards that had to be in compliance. In general, for a DCD to be considered acceptable, 80% of the duplicate pairs and 100% of the standards had to be in compliance with the QC criteria. When the number of duplicate pairs did not permit exactly 80% compliance (for example, 3 of 4 pairs would give 75% compliance), a fraction of duplicates in compliance slightly less than but near 80% was still considered to be acceptable. Less than 100% compliance on standards was allowed occasionally if the radiochemical analysis on the standard was near the accepted activity and if the laboratory had established a record of accurate radiochemical analysis on other subsamples of the standard in question. PARTICIPATING LABORATORIES Laboratories participating in the radiochemical analyses of samples from the NMIRS were Environmental Analysis Laboratory (EAL), Richmond, California; Eberline Instrument Corporation (EIC), Albuquerque, New Mexico; and Laboratory of Radiation Ecology (LRE), University of Washington, Seattle, Washington. The radionuclides measured were 905, (beta counting), 13765 (beta and gamma 239 d 240 ), 23942405, and 238 Pu (mass counting Pu (alpha pulse-height analysis), Pu an spectrometry), atl Dy (mass spectrometry and liquid scintillation counting), and (alpha pulse-height analysis). 241 There were 16,282 analyses, including the duplicate and standard samples of the QC program, requested of the three participating laboratories. The largest fraction of the analyses was performed by EAL: 65.6% (42.3% terrestrial and 23.3% marine). Slightly over one-fourth of the analyses, 25.5%, was performed by EIC. The balance, 8.9%, was analyzed by LRE. Table 2 summarizes the duplicate and standard analyses associated with the 15,745 analyses of soil, vegetation, terrestrial animal, marine organisms, and marine sediment 4