Appendix CRF - Part 3 - Northamptonshire County Council

Radiological Assessment 0820-2
Version 2
Appendix C Sensitivity Studies
C.1 Groundwater Pathway
This section presents the results from a set of sensitivity studies to assess how
calculated doses via the groundwater pathway are affected by alternative assumptions
about the disposal system. Results are presented that show the effect of variations in
leachate head within the landfill, of changes to the lifetime and efficiency of the cap,
in different assessment periods, and in the assumptions about the exposed group.
The results of these sensitivity studies are discussed in Section 5.1.
Radionuclide
Specific dose
(μSv y -1 per MBq)
1m head 2m head 5m head 10m head
Increase
1m - 10m
H-3 5.99E-23 6.01E-23 6.07E-23 6.17E-23 1.03
C-14 1.47E-07 1.47E-07 1.47E-07 1.47E-07 1.00
Cl-36 1.60E-06 1.60E-06 1.60E-06 1.60E-06 1.00
Fe-55 1.90E-36 6.63E-36 3.45E-35 1.20E-34 63.08
Co-60 2.92E-32 3.00E-32 3.63E-32 1.26E-31 4.33
Ni-63 2.92E-15 2.92E-15 2.92E-15 2.92E-15 1.00
Sr-90 1.70E-17 1.70E-17 1.71E-17 1.71E-17 1.01
Nb-94 6.84E-09 6.84E-09 6.84E-09 6.84E-09 1.00
Tc-99 1.15E-07 1.15E-07 1.15E-07 1.15E-07 1.00
Ru-106 7.67E-39 2.67E-38 1.39E-37 4.84E-37 63.09
Ag-108m 1.11E-12 1.11E-12 1.11E-12 1.11E-12 1.00
Sb-125 8.25E-35 2.87E-34 1.49E-33 5.20E-33 63.08
Sn-126 3.72E-07 3.72E-07 3.72E-07 3.72E-07 1.00
I-129 2.72E-04 2.72E-04 2.72E-04 2.72E-04 1.00
Ba-133 2.45E-24 2.46E-24 2.49E-24 2.53E-24 1.03
Cs-134 3.95E-36 1.37E-35 7.15E-35 2.49E-34 63.08
Cs-137 8.29E-19 8.29E-19 8.31E-19 8.34E-19 1.01
Pm-147 6.04E-37 2.10E-36 1.09E-35 3.81E-35 63.08
Eu-152 3.63E-25 3.64E-25 3.66E-25 3.71E-25 1.02
Eu-154 6.00E-28 6.03E-28 6.13E-28 6.29E-28 1.05
Eu-155 9.68E-34 1.00E-33 2.18E-33 7.58E-33 7.83
Pb-210 1.07E-18 1.07E-18 1.08E-18 1.08E-18 1.01
Ra-226 1.04E-06 1.04E-06 1.04E-06 1.04E-06 1.00
Galson Sciences Limited 79 14 July 2009
WS010001/ENRMF/CONSAPPCRF 629