Dose estimates for the solid waste performance assessment

Abstract

The Solid Waste Performancg Assessient calculations by PNL in 1990 were redone t o incorporate changes in methods and parameters since then. The ten scenarios found in t h e i r report were reduced t o three, the Post-Drilling Resident, the Post-Excavation Resident, and an All Pathways I r r i g a t o r. In addition, estimates of population dose t o people along the Columbia River are also included. report describes the methods and parameters used in the calculations, and derives dose factors f o r each scenario. concentrations, and r i v e r water concentrations needed t o reach the performance objectives of 100 mremlyr and 500 person-remlyr are computed. The attached In addition, waste concentrations, ground water Internal dose factors from DOE-0071 were applied when computing internal dose. External dose r a t e factors came from the GENII Version 1.485 software package. calculations were carried out on a spreadsheet. d e t a i l in the report f o r 63 nuclides, including 5 not presently in the GENII l i b r a r i e s. described in Appendix D.

Remediation and cleanout levels for Hanford site single-shell tanks

“…Once the ' "Cs in SST waste has decayed away, there are not many gamma emitters left to cause external dose. A notable exception, as shown in Appendix A, and the bounding radionuclide with respect to external radiation, is "' Sn (Schmittroth 1995 andRittmann 1994). This radionuclide has a half-life of 100,OOO years.…”

“…The dose factors give the annual external radiation caused by a curie of the radionuclide evenly distributed on every km2 of soil surface. The dose factors were taken from Rittmann (1994). (9: The number in this column actually represents the total relative hazard with respect to all pathways other than the groundwater pathway.…”