Just designed one of these for the local train co
We used a rotary vane pump. We used Ebsray pumps, but there are different options, talk to your local pump supplier. Ensure that the pump and the piping system and valves etc are not made from copper alloys or cast iron. Copper can cause precipitates in diesel and cast iron may shatter if cooled by water during a fire.
Remember that diesel is a combustible fluid, not flammable, but a properly designed piping system should be installed so that jets of diesel are not possible. You may wish to consider double mechanical seals for the service. We have treated the whole system has flammable and chosen Ex'd' rated motors and instruments, but this is not done by every one. Also consider the containment of the pipework leaking back from the 15 stories of pipework.
I am guessing also that there are boilers / water heaters in the same rooms that may increase the ambient temperature as well.