A conservative end effect keff bias curve for actinide-only burnup credit casks is presented
in this paper. Rather than performing axially burnup-dependent analysis, cask designers can, if
they choose to, analyze casks with a uniform axial burnup (at assembly average burnup value) and
add the keff bias values to conservatively bound the actinide-only end effect. Earlier studies
suggested 1-3% increase in keff to account for the end effect, but they included fission products
as well as actinides for their analyses.