Popis: |
Of the 177 tanks containing nuclear waste at the Hanford site, 68 have not been characterized based on sampling information. It may be possible to characterize 34 of the 68 unsampled tanks by using information from other sources, such as the Tank Characterization Database (TCD) and the Historical Tank Content Estimates (HTCE). This report lists predicted concentrations of 17 analytes along with the associated estimates of uncertainty for the T-200 series tanks (T-201, T-202, T-203, T-204), based on historical data and sample results from tanks other than the T-200 tanks. The main benefits of reduced sampling are reduced cost, reduced time to achieve acceptable characterization, and reduced exposure of sampling personnel. However, in order to characterize a tank on the basis of reducing sampling, the predicted tank averages and the associated uncertainties must be technically credible and useful. The objective of this report is to describe the approach to predict (without a sample) or estimate (from a single sample) the concentrations of the 17 analytes for the T-200 tanks. Sampling of these tanks and laboratory analysis of the samples is currently under way (sampling is scheduled for 03/27/97 through 04/21/97). This report briefly describes the statistical prediction techniques. |