You can find details of Gibraltar’s current radiation Emergency Response Plan at:-

http://www.environmental-agency.gi/pdf/RadiationEmergencyResponsePlan.pdf

ESG view is that the document is far more robust and thorough than any previous plan. Nevertheless it believes that the execution of such a plan would be virtually impossible to do given Gibraltar’s size, population density and international border.
It reiterates its long held view that nuclear submarines should not berth in Gibraltar.