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As the steady-state hydraulic calculations do not yet consider potential transient condi-tions within the pipeline system e.g. due to intended or unintended valve closure or power failure in sectionalizing valve stations and pump stations, respectively, some gen-eral assumptions have been made on pressure safety margins required to cope with these transient conditions. The safety margin required against potential overpressure has hereby been roughly estimated as 4 bar for the flow rates of the Preliminary Phase and of Phase I, and as 8 bar for the Phase II flow rates. These assumptions have, however, to be verified during the more detailed considerations referring to the hydraulic transient system behavior.
In order to avoid the hydraulic pressure gradient touching or cutting the hills near the pipeline end, the minimum pressure required in the pipeline system has been assumed as 2 bar.