Federal records show steady stream of oil spills in gulf since 1964
At least a handful of spills take place annually as a result of blowouts, hurricanes, lax pipeline maintenance, tanker leaks and human error, according to figures kept by the Minerals Management Service.
Deepwater Horizon alarms were switched off
Alarms and safety mechanisms on gulf disaster oil rig were disabled, to spare workers being woken by false alarms, chief technician at Transocean reveals.