The next phase of the DECOVALEX project ("D-2027") is soon to initiate.

This includes several tasks that are highly relevant to the LSSRs that are found within the search areas of all three Community Partnerships.

It is an appropriate opportunity to develop NWS numerical modelling capability and knowledge on coupled processes, which is required to support GDF design decisions and underpin the Safety Case.

The objectives of this work are to: •Develop and communicate a detailed understanding of how coupled processes could affect geological environments relevant to a UK GDF, and how the geosphere could consequently evolve.

Timescales relevant to a Geological Disposal Facility (GDF) for UK higher activity wastes shall be considered.

This will be achieved by participation in three tasks of DECOVALEX D-2027 that are relevant to UK LSSR, as outlined in Section 3 - Scope of work. •Capture how other modelling teams approach the tasks that the Contractor are participating n, and how this knowledge-share/collaboration throughout DECOVALEX D-2027 influences the Contractors own modelling approach. •Develop user-friendly, interactive communication tools (e.g., 2D/3D visualisation models) to capture key findings and communicate the results to internal and external stakeholders. •Organise one whole-project DECOVALEX D-2027 workshop/meeting within the UK.

This project will bring together ongoing and preceding work within an overall framework and identify knowledge gaps in the current programme of work.

This procurement will be conducted using the Business and Technical Services Marketplace which is a DPS.

Suppliers wishing to be considered for this opportunity will therefore be required to register for the Environmental category on the DPS.

Full instructions of how to register on BATS as a supplier can be accessed via the Atamis supplier portal once you have registered interest in the opportunity Please view details via the Atamis Supplier Portal https://one-nda.force.com/s/Welcome