Workers have moved the concrete and steel box some 200 metres to the side on the seabed while they evaluate their options.
An estimated 210,000 gallons of oil have been gushing every day from a pipe ruptured when the BP-leased Deepwater Horizon sank on April 22, two days after an explosion that killed 11 workers.
The high-stakes attempt to cap the leak, rife with expectations because it will take three months to drill relief wells to stem the flow, had been considered the best short-term solution to stave off the biggest US environmental disaster since the 1989 Exxon Valdez spill in Alaska.
“I wouldn’t say it’s failed yet,” Mr Suttles said.
“What I would say is what we attempted to do last night didn’t work.”
He said BP was also considering other methods to capture the flow. Among the options being considered was to plug the leak by injecting ground-up material in a “junk shot”.
“It has certain issues and challenges and risks with it, and that’s why we haven’t actually progressed up to this point. But we look and continue to see whether that’s a viable option,” Mr Suttles said.
“It’s all to do with we’re working in 5,000 feet of water in a very difficult, challenging environment.”
Workers have also sprayed dispersants over the slick to break it up and deploying hundreds of thousands of feet of boom to contain the spreading oil.
But environmentalists have warned that dispersants like Corexit were also nefarious to sea life.
“Those products don’t make the oil go away,” Gulf Coast Research Laboratory marine biologist Joe Griffitt said.
“It just falls to the sea bottom. That’s where you’ll find the sediments and the larvae. So the toxic effect is double.”
Mr Suttles said BP had anticipated encountering hydrates, but had not expected them to be as significant as a problem. Teams were evaluating whether the issue could be overcome by providing heat, methanol or other methods.
The dome had been expected to be operational on Monday local time and to collect about 85 per cent of the leaking crude by funnelling it up to a barge on the surface.