A decade ago, U.S. government regulators warned that a major deepwater oil spill could start with a fire on a drilling rig, prove hard to stop and cause extensive damage to fish eggs and wetlands because there were few good ways to capture oil underwater.

Yet over the past decade, the risks faded into the background as America thirsted for new oil sources, the energy industry mastered new drilling technologies and the number of deepwater wells in the Gulf swelled into the thousands. Then-President George W. Bush ushered in the new era with an executive order on May 18, 2001, that pushed his new administration to speed up the search for oil.

"I think it was certainly overwhelmed by the excitement of all the oil and gas that was starting to show up in the seismic studies and the technical excitement of how to drill these reservoirs," said Rick Steiner, a veteran environmental scientist who reviewed the document for McClatchy. "I think that had a way of subduing the real concern about the risk of these things."

The Shell plan, which Greenwire, an environmental news service, first reported last week, described a worst-case scenario for a deepwater blowout that in several instances reads like a preview of what's happened since BP's Deepwater Horizon rig began spewing crude into the Gulf seven weeks ago.

While noting that a major blowout was very unlikely, the Shell plan said: "Regaining well control in deep water may be a problem since it could require the operator to cap and control well flow at the seabed in greater water depths . . . and could require simultaneous firefighting efforts at the surface."

The BP disaster started when the drilling platform exploded, sending a towering wall of flames into the sky and killing 11 workers before it sank.

The 2000 Shell plan also cautioned that an oil gusher wouldn't behave the same way in deepwater as one would in shallow water, where most drilling to that point had been done. "Spills in deep water may be larger due to the high production rates associated with deepwater wells and the length of time it could take to stop the source of pollution," it said.

Dennis Chew, a marine biologist who helped prepare the plan but has since retired after 21 years with the MMS, studied it again this week and said: "Bottom line, this (BP) blowout was preventable." However, he blamed the accident on human error and BP "cutting corners. . . . "
Chew and two other members of the team that prepared the Shell plan told McClatchy that MMS scientists had analyzed the potential impact of deepwater blowouts as far back as the late 1990s.

"Ten or 15 years ago, there used to be 200-page (environmental impact statements) on nothing but spills," Chew said. "It got to where people got tired of wading through them."

The 2000s, however, ushered in an era of aggressive, government-backed offshore oil production. In May 2001, Bush, acting on recommendations from the oil industry, signed an executive order that required federal agencies to expedite permits for energy projects and paved the way for greater domestic oil exploration.

The rush to drill in deep water swept aside warnings from MMS scientists and others, experts said.