1. Backwards Compatibility L4 – L2 W. Weterings LBCC - 14

2. L4 PSB injection modification as currently planned Removal L2 equipment (and modify). Removal obsolete cabling. Installation L4 equipment. Installation L4 cabling. Minimum intervention time -> 3 Months.

3. De-commission L2 equipment. (radioactive) Storage of L2 equipment. If possible leave L2 cabling in place. Removal obsolete cabling. Installation L4 equipment. Installation L4 cabling. Additional intervention time -> 2 Months. L4 to L2 Conversion time -> 5 Months. Keeping Linac2 as a backup by de-commissioning

4. Additional installation space for L4 equipment. De-commission L2 equipment in tunnel. If possible leave L2 cabling in place. Removal obsolete cabling. Installation L4 equipment. Installation L4 cabling. Additional intervention time -> 1 Months. L4 to L2 Conversion time -> 4 Months. Keeping Linac2 as a backup & leave L2 equipment in place (BA361)

5. Space management, Integration (BA361). Campaign to remove already obsolete cabling, equipment in coming shutdown. Additional budget required for vacuum chambers (current plan is to modify existing pipes for L4). Investigate if KSW position for L4 is compatible with L2 operation. General Issues