Research and analysis

Geological Disposal: Design Status Report

The purpose of this report is to document the rationale behind the key design developments, to provide an overview of the engineering design work undertaken and provide support to the published design reports (Generic Transport System Design and Generic Disposal Facility designs).

Documents

Geological Disposal Design Status Report

Details

A geological disposal facility (GDF) will be a highly engineered facility, located deep underground, where the waste will be isolated within a multi-barrier system of engineered and natural barriers designed to prevent the release of harmful quantities of radioactivity to the surface environment. To identify potentially suitable sites where a GDF could be located, the Government is developing a voluntarism approach based on working with interested communities that are willing to participate in the siting process. Development of the siting process is ongoing and no site has yet been identified for a GDF.

In order to progress the programme for geological disposal in the absence of a specific site, RWM has developed generic, illustrative disposal designs for three host geological environments and an associated generic transport system design. This approach also provides RWM with a basis for developing waste package specifications, using the established Letter of Compliance (LoC) disposability assessment process, to identify if waste packaging proposals from waste producers are consistent with the requirements currently foreseen for transport, operational and long-term safety. These host geological environments are typical of those being considered in other countries, and has been chosen because they cover the range of issues that may need to be addressed when developing a GDF in the UK. They are:

  • higher strength rock, for example, granite
  • lower strength sedimentary rock, for example, clay
  • evaporites, for example, halite

In the future, these illustrative designs will be tailored to the specific boundary conditions of UK geology and the waste inventory, and also constraints resulting from the siting process. It is expected that these illustrative designs will continue to be required and updated as the designs move forward through the process from their current illustrative status through the conceptual and preliminary design stages and until a detailed design for a GDF at a specific site is developed.

RWM has also developed a generic transport system design. This design describes the operations required commencing at waste producer’s sites, to ensure safe and efficient transport of transport packages through the public domain to a GDF.

The purpose of this Design Status report is to document the rationale behind the key design developments, to provide an overview of the engineering design work undertaken and provides support to the published design reports (Generic Transport System Design and Generic Disposal Facility designs). It is not intended for this report to present the totality of the design work undertaken, but instead to support any future design development work by providing a summary of the extent and justification for the design decisions taken.

This report will be periodically updated to include design enhancements that are adopted to the geological disposal facility and its transport system to support any future design development work and to provide reference to the underpinning source information.

Published 16 October 2016