Containment Dome Almost in Place Over Leaking Undersea Oil Well

The big dome is nearly there.

With the guidance of undersea robots, crews in the Gulf of Mexico are gingerly lowering the 100-ton concrete-and-steel box over a blown-out well on the ocean floor this morning. If all goes well—and we won't know until Sunday when it's fully operational—it will collect 85% of the oil spewing into the Gulf and funnel it up to a tanker.

BP engineers have moved the four-story containment dome -- which was seen as the best short-term way to stem the flow from a ruptured oil well -- off to the side on the sea floor and will take two days trying to come up with a solution, Doug Suttles, chief operating officer, told reporters.