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Current and Potential Impacts of the Gulf Oil Spill. Megan Westmeyer. Timeline. Deepwater Horizon floating rig exploratory drilling 50 miles southeast of Venice water nearly 1 mile deep only 40-50 rigs in Gulf drilling this deep April 20, 2010 – explosion – methane gas
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Current and Potential Impacts of the Gulf Oil Spill Megan Westmeyer
Timeline • Deepwater Horizon • floating rig • exploratory drilling 50 miles southeast of Venice • water nearly 1 mile deep • only 40-50 rigs in Gulf drilling this deep • April 20, 2010 – explosion – methane gas • April 22, 2010 – rig topples, oil begins to leak from well in sea floor • Blow-out preventer failed • Three leaks, one has been sealed
Current situation • Leaking ~210,000 gallons (5,000 barrels) per day • Exxon Valdez in 1989 was 11 million gallons • Attempted to place large “funnel” over leak on Saturday 5/8 • Gas-water crystals clogged • Mitigation: booms, skimming, burning, dispersants (bad weather disrupts) • Oil started showing up on shore over the weekend
What next for BP? • Drilling relief well (2-3 months) • Retry box, but higher in water column • Other kind of box with heat source to prevent crystallization • Pump mud and concrete into blowout preventer (2-3 weeks) • Cut the pipe, connect larger pipe – could make it worse, could contain completely
Is Gulf seafood safe to eat? • If it makes it to market, yes • Affected portions of Gulf closed to harvest • Federal and state agencies testing seafood in Gulf and on land (established benchmarks first) • Scientists testing Gulf water and sediments
Fishery Closures • From http://sero.nmfs.noaa.gov/ • Current Federal Closure • Office of Response and Restoration – daily updates and projections • http://response.restoration.noaa.gov • Also see Louisiana Department of Wildlife and Fisheries at www.wlf.louisiana.gov for state water closures and oyster closures
Affected seafood products • Gulf seafood production • Oysters • Shrimp • Crab • Snapper and grouper
Oysters • Immobile, filter feeders • 67% of U.S. oysters • LA dominates; substantial production in TX, MS, wFL • Affected portions of LA and MS produce >50% of U.S. oysters • MS scheduled to close on April 30; re-open in fall
Shrimp • Spring and summer - adult shrimp leave the salt marshes and move offshore to spawn • Affect adults and offspring (next year’s crop) • Gulf of Mexico produces about 73% of the U.S. harvested shrimp • Dominated by LA, TX close second, AL, MS, and wFL smaller but substantial amounts • Closed areas are about 40-45% of Gulf production or about 30% of national production
Crab • Crab harvest in near shore waters - harvest typically peaking during the summer and spawning peaking during the fall • Most of Gulf harvest in LA – 26% of U.S. harvest
Snapper and grouper • More likely to be affected in the long-term • Spawning throughout the late spring and summer • Larvae and juveniles inhabit shallower and inshore waters – vulnerable to chemicals • Dispersants may make oil more available to adults
Dispersants • Separates the oil into smaller droplets • Dispersed throughout the water column • Prevent surface slick – affects beaches, marshes, animals – immediate damage • Does not destroy or eliminate oil – dilutes and alters until natural degradation • Where does it go? – complex currents, water vs sediment • What does it do? – food chain, toxicity
Sea Grant Info Hub • www.gulfseagrant.org • Developments • Recovery • Economic Value • Human Health • Oil and Wildlife • Maps and Map Services • Background Information
Websites • NOAA Fishery Closures http://sero.nmfs.noaa.gov/ • NOAA oil spill daily updates and predictions http://response.restoration.noaa.gov • Louisiana Department of Wildlife and Fisheries closures www.wlf.louisiana.gov • Gulf Sea Grant information hub www.gulfseagrant.org • For more info contact: Megan Westmeyer at mwestmeyer@scaquarium.org