Implication of the displacement of the T1 primary target in the west area at the CERN SPS

As soon as the transfer line T12 for proton injection into the LHC must be installed, the T1 primary target has to be at least partly dismantled, as its shielding would block the passage of the beam. Even though the installation of T12 is only foreseen for later, in view of sharing of workload related to the SLI project, it is preferred to move the primary production target T1 for the West Area to its new position already in the shutdown 1999/2000. The new position of the target requires major modifications of support structures in TCC6, of the transfer line towards T1 and of a more than 500 metres long section of the H3 secondary beam in the West Area, all to be completed in the 1999/2000 shutdown. To allow the work to be finished in time, part of it (including some civil engineering in TT4) is already done in the 1998/99 shutdown. In this memo the necessary modifications are described, cost estimates are given and a planning is provided.