E2 Round-up: BP ups estimate of oil capture, Shell keeps pushing Alaska offshore project, underwater oil plumes called an emerging danger

* Shell hopes to reassure regulators that its offshore drilling plans in Alaska are safe

The company’s controversial plans to drill in Arctic waters — never popular with environmentalists to begin with — are facing new scrutiny following the Gulf of Mexico oil spill.

Shell, in a letter Monday to the federal Minerals Management Service, vowed an “unprecedented” response in the event of a spill, The New York Times and other outlets report. The company hopes to begin exploratory drilling off Alaska’s northern coast this summer.

The plans include having a containment dome at the ready in Alaska to contain a leaking well if there’s an accident. And the plan would take into account the problem that derailed BP’s effort to use a containment dome in the Gulf spill: the formation of ice-like crystals made of gas and water that clogged the structure.

“Shell also said it would be ready to apply dispersal agents below water ‘at the source of any oil flow’ after ‘all necessary permits are acquired,’ ” the Times reports.

“The company also said it would work to prevent a spill from happening, including refining how it drills, increasing the frequency of inspections of its blowout preventer to seven days from 14 — the blowout preventer failed in the Gulf spill — and adding a remote underwater vehicle nearby that would be capable of working on the blowout preventer.”

But environmentalists, who fear that a spill would harm whales and other sensitive species, are not convinced. The Pew Environment Group, in a statement, said that “basic questions” about Shell’s response capability remain unanswered.

* Huge underwater oil plumes raise fears, but how real are they?

A slew of stories in recent days highlight fears among marine researchers that massive undersea oil plumes from the Gulf of Mexico spill are a major threat to marine life.

AFP reports: “Giant plumes of oil floating deep in the Gulf of Mexico could create a new 'dead zone' of oxygen-depleted waters unfit for marine life and wreak environmental damage that will take generations to overcome, scientists warned Monday.”

And AP looks at threats to delicate coral reefs.

However, the National Oceanic and Atmospheric Administration is urging caution about reports of the massive plumes.

“Jane Lubchenco, head of the National Oceanic and Atmospheric Administration, called media reports of large underwater oil plumes ‘premature,’ adding that research conducted by an academic ocean institute was inconclusive,” the Los Angeles Times reports.