The federal government today defended its decision to pause a test of the new cap that promises to control the Gulf oil leak, as oil continued to spew from BP's broken well.
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BP began tonight the process of testing the 150,000-pound cap that it hopes will ultimately contain the Gulf oil flow completely. Government scientists and the Coast Guard had put the integrity test on hold out of concern that a misstep could make the leak even worse.
"We did this to make sure that we were taking due care, and in some cases, maybe an overabundance of caution to make sure we didn't do any irreversible harm to the well," Coast Guard Adm. Thad Allen said in a news conference today. "It was advisable to take a 24-hour break to make sure we're getting it right."
On the 86th day of the crisis, Louisiana Gov. Bobby Jindal expressed support for the decision, underscoring the high stakes.
"We're at a point where we can't afford to make this worse," Jindal said. "We cannot afford for them to do damage to this well."
Once the test begins, BP will slowly close three valves on the cap, one section at a time. Pressure will be increased at six-hour intervals, with higher pressures indicating that the cap has worked and oil is no longer leaking. BP will monitor the pressure readings minute by minute.
While the test is going on, BP will disconnect the vessels collecting oil, the Helix Producer and the Q4000. In their place, 40 skimmers are standing by to collect any oil that makes its way to the surface.
Concerns about the plan center on the piping inside the blown out well that extends about 13,000 feet into the sea floor. If there are any weak spots in that pipe, high pressures could spring new leaks.
"They have to be very careful when they close it down," said Dr. Don Van Nieuwenhuise, a professor of geoscience at the University of Houston. "[They have to] make sure that pressure doesn't come up quickly and cause any of the pipes to rupture."
During the testing process, BP is also pausing its effort to drill relief wells, the permanent solution to plug the well that are now 4 feet away from the side of the well and 150 feet from the target depth.
ABC News' Russell Goldman contributed to this report.