CERN AC Note (2000-03)-General description of the CNGS Project

5. CNGS and the environment

The amount of concrete to be poured is calculated at 12’200 m3, and the site is supposed to be supplied with this amount from the two nearby concrete mixing centres at either Thoiry or Crozet. Concreting work will last some 18 months, totalling six loads per day along roads RD35a and RD35.

Components to be installed for the project will be brought in via Point BA4 of the SPS through the access tunnel. The 500 blocks of iron for the hadron stop can be transported in loads of five at a time. The 100 magnets for the proton line must be brought in one by one. The iron blocks will be brought from CERN’s Meyrin site via road VC5 at a rate of two trucks per day during the approximately two month installation phase. The magnets will come from CERN’s Prévessin site, near SPS Point BA4.

When the CNGS is running, its beam will be controlled from the SPS-LHC control room at the Prévessin site, and there will be no major traffic during the seven months of operation each year. During shutdowns, only occasional loads of defective equipment are likely to be transported.

5.6 Land ownership aspects

For earlier CERN projects, the French State acquired and made available the necessary land to CERN. For SPS, 412 ha were acquired during the nineteen-seventies. SPS Point BA4 is located on one of these pieces of land. In Switzerland the depth of the structures is so great that they are below the useful depth level. The structures for the CNGS in France will be located in tunnels. There is therefore no land ownership impact from the CNGS project either in France, or Switzerland.

5.7 Radiation safety aspects

Although neutrinos themselves have no effect on matter or living organisms, their production by means of a proton beam generates radioactivity, which remains however confined to the tunnels. The calculations by radiation safety experts show that no ionizing radiation will reach the surface directly and that any radioactivity released via air and water will be very much lower than the natural radioactive background in the region.

In any case, the CNGS project will be formally supervised by the French and Swiss authorities. The project will be included as part of the Basic Nuclear Installation (INB 5) Convention for the LHC and the SPS between CERN and the French government. Before obtaining the requisite permission for operation CERN will first submit its project and safety arrangements to the French national Directorate of Safety in Nuclear Installations (DSIN 6) which manages the INB’s and to the Federal Swiss Public Health Office (OPRI 7).

5.8 Safety

Like LEP and the LHC, the CNGS will be subject to the provisions governing basic nuclear installations (INB). In particular, the INB procedure includes in its initial phase a hazard study, identifying possible risks and identifying the principles of prevention.

5 "Installation Nucléaire de Base"
6 "Direction de la Sûreté des Installations Nucléaires"
7 "Office de Protection contre les Rayonnements Ionisants"

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