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The results from 80-week boil-down tests are located in Table 4-6. Section 6.2.1.3 provides further explanation on the use of these rates. 4.1.3.1.4 Radiolysis The results of experiments simulating the effects of radiolysis products on corrosion can be found in Table 4-7. Section 6.2.1.4 further explains the use of these rates. 4.1.3.1.5 Sensitization of Stainless Steel This section does not report any data on corrosion of sensitized stainless steel. The rationale for this can be found in Section 6.2.1.5. 4.1.3.2 Steels Containing Neutron Absorbers (Boron and Gadolinium)

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Roberts et al., 1990 NOTES: * signifies minerals that are in the DataO.ymp.RO database measured density (otherwise it is the calculated density) The zeolites above that do not have any indication of their formational environment are rare and not expected to form in the WP. However, they are presented in the table for completeness." signifies minerals that were added for the new database, DataO.ymp.R2 MDL-DSU-MD-000001 REV 00101 October 2002 Geochemistry Model Abstraction and Sensitivity Studies for the 21 PWR CSNF Waste Packages VALIDATIONThe validation approach uses two goodness of fit methods for the validation of the model abstraction: (1) the R2 correlation figure of merit was used for the pH abstraction, for the HCO3-drop abstraction, for the HCO3-concentration abstraction, and for the U-loss abstraction; and (2) the chi-squared was used to validate the boron abstraction (per the TWP BSC 2002b). The abstraction model will be used to calculate probability distributions that will not be used directly in performance assessment calculations, public safety related issues, or other LA design activitiesThe acceptance level for the linear regressions was a value of R2 > 0.8 and an F-statistic significance of less than 0.10. As can be seen in Table 47 below, all of the regression analyses fall above an R2 of 0.8 and most fall above 0.9. The lowest values of R2 occur for time intervals where the pH fluctuates greatly. For most cases, the greatest fluctuation of pH occurs early in the run while the A5 16 steel degrades rapidly. Drastic pH shifts also occur later in the run, when the last of a component (such as the slowly degrading neutronit or fuel) has completely degraded, and that component is no longer controlling the pH. The goodness of fit is also considered acceptable based on the significance of the F-statistic. A value of 0.01 for the significance of Fstatistic indicates that there is a 99% chance that the relationship between the variables is significant and not merely due to chance. Therefore, based on the F-statistics in Table 47, all of the regressions listed have at least a 98% chance that the relationship between the variables is significant. Though many are much higher than this with a 99.9 to 100% chance.Since the B release from the waste package is calculated using a formula based on simple mass balance, the chi-squared test was used for the validation. The acceptance level for the chisquared test was a rejection probability of less than 10% (TWP, BSC 2002b). As mentioned before, B in the waste package depends solely on the corrosion rate of the neutronit and the flushing (drip) rate. With the current rates used in this abstraction, a set of six possible combinations were used to calculate the rejection probability. The chi-squared statistic (x2) for each of these cases is presented in "B-loss-validation.xls" in Attachment I. The x2 values show that in all cases, the B in the waste package predicted by the model presented in Section 6.2 shows less than a 0.5% rejection probability (Scheaffer an...