A growing collection of crippled equipment now litters the ocean floor near a ruptured oil well gushing crude into the Gulf of Mexico off the coast of the United States, the remnants of a massive rig that exploded weeks ago and the failed efforts since to cap the leak.
On the surface, nearly a mile up, a fleet of ships moved to deploy the latest stop-gap plans hatched by BP engineers desperate to keep the Deepwater Horizon disaster from becoming the nation's worst spill.
An estimated 3.5 million gallons has risen from the depths since the April 20 explosion that killed 11, a pace that would surpass the total spilled in the Exxon Valdez disaster by June 20.
A day after icelike crystals clogged a four-story box that workers had lowered atop the main leak, crews using remote-controlled submarines hauled the specially built structure away and prepared other long-shot methods of stopping the flow.
One technique would use a tube to shoot mud and concrete directly into the well's blowout preventer, a process that could take two to three weeks.
Chief operating officer Doug Suttles said BP was also thinking about putting a smaller containment dome over the massive leak, believing that it would be less vulnerable because it would contain less water. The smaller dome could be ready to deploy on Tuesday or Wednesday.
The company was also now debating whether it should cut the riser pipe undersea and use larger piping to bring the gushing oil to a drill ship on the surface. Cutting the pipe would be tough, and was considered the less desirable option, said Mr Suttles, who gave no indication of exactly what the next step would be.
Meanwhile, thick blobs of tar washed up on Alabama's white sand beaches, yet another sign the spill was spreading.
The original blowout was triggered by a bubble of methane gas that escaped from the well and shot up the drill column, expanding quickly as it burst through several seals and barriers before exploding, according to interviews with rig workers conducted during BP PLC's internal investigation.
As the bubble rose, it intensified and grew, breaking through various safety barriers, said Robert Bea, a University of California Berkley engineering professor and oil pipeline expert who detailed the interviews.