The sinking of the Deepwater Horizon oil rig in the Gulf of Mexico, and the subsequent gush of millions of litres of petroleum, exposed a startling lack of tools for cleaning extensive spills. A month after the explosion on the BP-leased rig, the United States Coast Guard issued a call for new technologies that could help control the catastrophe.
The request detailed five “technology gap areas” related to oilspill response, including methods to cap rogue wellheads, better skimming vessels, next-generation oil dispersants and fresh methods to detect and track spreading oil. The public has not held back: within two weeks, the Coast Guard screened more than 420 submissions and had over 1 000 yet to be evaluated. While Coast Guard officials would not release details about individual proposals, officials say that at least a handful of the ideas in the white papers will eventually be tested, although none has been fast-tracked to the gulf.
The Coast Guard’s outreach is a direct response to the lack of feedback BP offered for ideas that flooded the company after it solicited input from the public, says Coast Guard Lt Cmdr CT O’Neil. This experience, he says, unlike that one, will “provide a process by which people will know whether their idea can help in the current fight against the oil”.
Many firms, large and small, see an opportunity in the aftermath of the spill. “After the Exxon Valdez, the entire industry transitioned to double-hulled tankers,” says Glenn Rink, the founder of start-up AbTech Industries, whose Smart Sponge polymer has now attracted interest from BP after years of rejection by energy firms. “The question is, what sweeping changes will come from this disaster?” – Erik Sofge
The future of spilled oil
What will happen to the millions of litres of crude pouring into the Gulf of Mexico? — Amber Angelle and Cassie Rodenberg – Amber Angelle and Cassie Rodenberg
Waves and wind mix oil with water to form a substance resembling chocolate mousse. Up to 40 per cent of the surface oil evaporates, leaving behind more viscous compounds. Plumes of crude deep below the waterline are not broken down by sunlight, and they spread with undersea currents.
Pellet-size balls form on the surface as the oily mousse breaks up. Plankton absorb the oil/water mix and excrete tainted metabolites that settle to the bottom, damaging larval shrimp, crab and fish. On beaches, oil starves plants of nutrients and kills emerging shoots.
The surface oil has broken into hydrocarbon components that allow water and carbon dioxide to reform. In the wetlands, small creatures that depend on dead plant material for nutrients have exhausted that supply. Numbers of crab and shrimp plummet.
Beaches and wetlands appear rehabilitated, but asphaltene – oil residue mixed with sediments – lingers beneath the sand and in pools in the bayous. Invasive plant species have taken root; the annual loss of wetlands accelerates from 64 km² to up to 103 km².
Underwater oil plumes still persist. Bacteria feasting on the oil consume oxygen, creating a shortage that suffocates life. Squid, sperm whales and whale sharks decline. The plumes may eventually drift into the Atlantic, where they threaten coral reefs.
Caches of oil, trapped in underground pockets, linger on shore. These do little harm unless unearthed by storms, animal activity or man-made disruptions. Above ground, wildlife has returned but species’ life cycles have been altered.