Confessions of an Offshore Geek

The oil industry is usually pretty tight-lipped when it comes to mistakes, but Peter Marshall, a former Shell engineer well-known for his work helping the industry improve the design of off-shore platforms, is willing to talk.
During a lunch speech Wednesday at OTC, Marshall ran through some of the accidents of years past and what the industry took away from it. For example, one of the first major oil spills from an offshore platform — a 1969 accident off Santa Barbara, Calif. — washed oil onto local beaches. The lesson: public opinion can have a huge impact on the business.
A platform explosion and fire off Bay Marchand, La. that killed two workers taught the industry that the Teflon seals they had been relying on weren’t all they were cracked-up to be. The industry also developed well shut-off valves that were located at the well-head on the ocean bottom instead of on the platform, where they were more likely to be damaged.
Hurricane Betsy in 1965 gave the industry one of its first examples of a floating piece of equipment breaking free of its mooring and slamming into another unit, the fixed platform at West Delta 134D. Marshall showed pictures of the subsea damage that he took while in a minisub. On the next trip that sub became tangled into the debris, and thus was learned another lesson: “It’s better to send a remote controlled camera down while keeping the engineering topside to look at the pictures.”
Hurricane Camille in 1969 created 70-foot undersea mudslides that took out a fixed-leg platform, a lesson that seemed to have been forgotten when Hurricane Ivan in 2004 wiped out a number of undersea pipelines with mudslides.
The toppling of the drilling rig on Shell’s Mars platform during Katrina in 2005 highlighted the need to build tougher clamps for move rigs at standards higher than those applied to fixed platforms in shallower water. Those clamps failed.
“And you need to be sure to tighten the tie-down bolts before you evacuate for a storm,” Marshall said.