Appendix CRF - Part 3 - Northamptonshire County Council

The approach drives the correct behaviour down to the consignor in respect of
the waste hierarchy because the approach enables remaining nuclide capacity
(hence price) to be directly related to the environmental risk of that nuclide.
The approach addresses the optimisation principle because the remaining
capacity of the landfill is continuously optimised in a manner that ensures the
overall risk guidance levels are not exceeded and the model will enable the
operator and regulator to make informed choices.
The capacity of the landfill is administered in a manner that ensures dose limits
and constraints will not be exceeded with a significant safety factor to account for
uncertainties.
The approach maintains flexibility to account for the uncertain overall inventory of
decommissioning wastes to be produced as required by regulatory guidance (ref
19).
8.16.7 For the purposes of authorisation this approach can be described as maintaining
a condition in which the remaining radiological capacity for a particular nuclide or
wastestream, which is proposed for receipt, is greater than zero, taking into
account the wastestream received to that point in time. Where:
Radiological capacity is the amount of radioactive material that can be consigned
to a site without any of the potentially exposed groups considered receiving a
dose above a specified criterion, for the specific scenario.
For a single radionuclide, the radiological capacity (in Bq) can be easily
calculated by dividing the dose criterion (expressed in Sv) by the maximum
specific dose for that radionuclide (expressed in Sv/Bq). For mixtures of
individual radionuclides, the capacity can be simply apportioned (e.g., half of the
overall capacity to each of two radionuclides). In the case of waste streams,
however, in which the proportions of different radionuclides are fixed, the
calculation of capacity must consider both the specific dose and the activity
ratios.
The radiological capacity for radionuclide Rni in a waste stream (RCi) is given by:
RC
i
where:
DC
i
SD
f
Application for disposal of LLW including HV-VLLW under RSA 1993,
for the East Northants Resource Management Facility:
Supporting Information
f
i
i
fi is the fraction of the overall activity arising from Rni (such that fi=1)
SDi is the specific dose from Rni
DC is the dose constraint
Furthermore:
Total activity limit for
each radionuclide (Bq) = Dose Limit (Sv/y).Waste Activity (Bq)
Dose Estimate (Sv/y)
July 2009
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WS010001/ENRMF/CONSAPPCRF 408