Preliminary analytical repository flow model

Abstract

This memo describes a preliminary model that predicts the flow of dissolved nuclear waste in an underground repository. The model is based ou the flow of water that enters regions of the reposi tory in which the waste is actually contained; it is expected to be an improvement over the current ap proach that assumes the waste flow is proportional to total flow of water along various pathways. The repository flow model is intended for implementation in the TASC WASTE computer code.

NUTRAN: a computer model of long-term hazards from waste repositories

“…This model (derived in Ref. 18) incorporates a more accurate description of the division of waste between forma tion flow and the shaft than the porportional model described in Section 5.3.1. Unlike the REPFLO method, it does not re quire external calculations of storage room flow paths.…”

“…The transport of daughter nuclides is computed in WASTE assuming that the daugh ter and precursor have the same retardation factor. When the retardation factors of a decay product daughter and its precur sor differ, the contribution of the daughter to dose is compu ted as a constant multiple of the contribution which would be [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] computed if equal retardation factors were assumed. This con stant multiple is the measure of the reconcentration effect.…”