Strategic Guidance on the Management of LLW and ILW / LLW ...

LLW Repository LtdNational Waste ProgrammeNWP/REP/011Issue 2.1 – Jan 2013Page 3 of 58Executive SummaryPond furniture, defined as the metallic architecture used for the storage and handling of irradiatedfuel in cooling ponds which has been or is being stored under water, is a ubiquitous waste withinthe Nuclear Decommissioning Authority (NDA) estate. Decommissioning of fuel cooling ponds willgenerate (retrieve) a significant volume of metallic waste. Despite the significance of thiswastestream, historically there have been limited efforts to analyse detailed information about thecharacteristics of this waste and the approaches site licence companies (SLCs) are using, orintend to use, for management of this waste. The objective of this strategic guidance document isto provide a cross-NDA estate compilation of this data on inventory and management approachesas a vehicle to support the transfer of knowledge, best practice, lessons learned and innovationacross the NDA estate.An extraction, review and refresh of data from the United Kingdom Radioactive Waste Inventory(UKRWI) 2010 estimates that the total volume of pond furniture classifiable as low level waste(LLW) or intermediate level / low level (ILW / LLW) cross boundary waste in the NDA estate is14315m 3 . This waste inventory is predominantly located at the Sellafield site (some 95% of thetotal volume) and consists mainly of stainless steel. The volume is dominated by LLW, albeit thatmuch is expected to be at the upper end of the LLW category. In the near term, it is expected thatthe majority of the waste will arise from decommissioning of the fuel ponds at Research SitesRestoration Ltd (RSRL) Harwell site, the Magnox Ltd. sites (Bradwell, Chapelcross, Dungeness A,Oldbury and Sizewell A) and the legacy pond facilities at Sellafield (First Generation MagnoxStorage Pond (FGMSP) and Pile Fuel Storage Pond (PFSP)).Historically, NDA estate SLCs have relied on disposal, either directly to the Low Level WasteRepository (LLWR) or else interim storage pending disposal to the Geological Disposal Facility(GDF), but there is increasing utilisation of decontamination and diversion to alternative wasteroutes such as metal melting.Significant efforts have been expended by SLCs (particularly Magnox Ltd.) into ongoing researchand development (R&D) programmes to identify and implement new approaches for managementof pond furniture. Examples of techniques trialled through these R&D programmes include foamdecontamination, acid decontamination, Decontamination For Decommissioning (DFD),Decontamination For Decommissioning Electrochemical Ion Exchange (DFDX), metal milling andnitrocision.Through review of the routinely used processes for management of pond furniture and widerdiscussions with the SLCs, a generic decision-making process to support waste managementoptioneering has been developed. This illustrates the relationship between waste managementdecisions and outcomes (using the waste management hierarchy), demonstrating howcombinations of decisions can be used to drive to waste management solutions of leastenvironmental detriment. This is intended to inform and support the detailed optioneeringprocesses used by the SLCs.A range of issues and opportunities have been identified and reviewed. Management of theseissues, and exploitation of the opportunities, provides a mechanism to improve and optimise theefficacy of waste management practices for pond furniture within the NDA estate.A company owned by UK Nuclear Waste Management LtdNOT PROTECTIVELY MARKED