Accelerator Tunnel Layout (G01) Nick Gazis Senior Mechanical Engineer Review of ESS Accelerator Conventional Facility Design

Outline ESS plant layout Integration – Accelerator Tunnel (AT) – Front-End Building (FEB) – HEBT Loading Bay (HLB) – Beam Dump (BD) – Accelerator to Target & Gallery Support Area (A2T & GSA) Conclusions NG - Accelerator Tunnel Layout G012

ESS accelerator areas NG - Accelerator Tunnel Layout G013 HLB FEB BD AT A2T FEB: Front-End Building AT: Accelerator Tunnel HLB: HEBT Loading Bay A2T: Accelerator to Target GSA: Gallery Support Area BD: Beam Dump lvl 110: first floor lvl 100: ground floor lvl 090: underground G01

Accelerator Tunnel (AT) design NG - Accelerator Tunnel Layout G014  1. Drift Tube Linac (DTL) 2. DTL to Spoke   3. Spoke 4. Medium Beta  Linac (MBL)

Accelerator Tunnel (AT) issues The high schedule pressure results in accumulating mistakes and less mature design Issue: The accelerator design is in preliminary stage and the site infrastructure design is finalized and concrete is being poured Risk: Our proposals and estimations include high error margins Mitigation: Use of space holders and mock-ups for as real as possible space evaluation Issue: The design is complex and the turn around is slow (every 3 weeks) Risk 1: Work on outdated models and overlapping inconsistent results Risk 2: We might have to review the accelerator design according to the changes in the site infrastructure Mitigation: Time spent on monitoring changes in a weekly basis, ad-hoc solutions and work on agreeing on dedicated space envelopes per system Issue: After agreeing on the requirements, their implementation is not always straight forward and there is no verification process (e.g. fire doors in the FEB, HLB) Risk: The layouts can become dysfunctional and/or miss the actual needs reflected by the requirements (with a future risk on cost for later corrections) Mitigation: Coordination meetings and iterations for coming up with valid revised concepts and layouts Issue: Absence of drainage system in the Accelerator Tunnel Risk: Any potential leaks inside the tunnel will result in areas with accumulated liquids Mitigation: Proposal for a ditch along the tunnel or local low points NG - Accelerator Tunnel Layout G015

Front End Building (FEB) design NG - Accelerator Tunnel Layout G016 HVAC  lvl 100 Water skids, cooling manifolds, entrance to the gallery etc.  lvl 090 Racks, cooling pipes, entrance to the AT, etc.

Front End Building (FEB) issues NG - Accelerator Tunnel Layout G017 Issue & Risk 1: Not enough space for the water skids and the pipe routing for the cooling water Mitigation: Working on increasing the space of level 100 Issue & Risk 2: Fire door limiting the width and height of the opening between FEB and AT Mitigation: Integrate the fire door in the double-door safety system on the other side of the chicane -lvl 100- HVAC -lvl

Front End Building (FEB) issues NG - Accelerator Tunnel Layout G018 -lvl Issue & Risk 3: FEB elevator is not wide enough to transport accelerator equipment for installation or replacement (e.g. SPK CM) Mitigation: Drop hatch in the other side of the FEB level 090

HEBT Loading Bay (HLB) design and issues NG - Accelerator Tunnel Layout G019 Issue: Fire doors implemented in the transportation corridor of the heavy equipment Risk: Narrows down the corridor width Mitigation: Review of AD installation and transportation processes to define if the new values are acceptable

Beam Dump (BD) design and issues NG - Accelerator Tunnel Layout G0110 Issue: The design installation of the BD is not finished Risk: No possibility to maintain and/or replace the BD. Mitigation: The BD can be accessible for maintenance by disassembling accelerator equipment and removing the concrete floor of the AT

- Accelerator to Target (A2T) design and issues - Gallery Support Area (GSA) design and issues NG - Accelerator Tunnel Layout G0111 Issue: The GSA should be enclosed by walls (NSS requirement) Risk: That leads to a need for HVAC room Mitigation: AD proposes to have the area wall free Issue: No power/heat can be dissipated to the air from the GSA (NSS requirement) Risk & Mitigation: Investigating the increased cost solution of water cooling racks 100 m2

Accelerator Tunnel (AT) -G01- Conclusions We have a preliminary accelerator design and a site infrastructure design is finalized and now concrete is being poured We have done a good team work to integrate the machine in the Accelerator Tunnel (G01) and the progress is considerable The preliminary accelerator design is in place and we are trying to reach the next state of design maturity Several issues were presented in this talk and mitigations for all of them are being worked as we speak NG - Accelerator Tunnel Layout G0112