Restrictions likely in the Gulf of Mexico New regulations are expected for oil c ...

Restrictions likely in the Gulf of Mexico New regulations are expected for oil companies working in the Gulf of Mexico, following the recent oil spill and loss of a drilling rig, reports Judith Gurney. These are likely to include tougher rules regarding E&P, and possibly even a moratorium on exploratory drilling. On 20 April, Deepwater Horizon, a semi-submersible drilling rig owned by TransOcean, began drilling BP’s Macondo prospect in 5,000 feet of water, 50 miles off the coast of Louisiana. BP had acquired Macondo in a Minerals Management Service (MMS) lease sale in March 2008 with partners Anadarko and Mitsui. The drilling plan submitted to the MMS included the drilling and temporary abandonment of two exploratory wells. The first exploratory well was halted due to damages to the drilling rig after Hurricane Ida in November 2009. Deepwater Horizon had finished drilling the well to just over 18,000 feet and had installed a steel production pipe into the well. That evening, Halliburton, who was handling the cementing process, had just completed cementing the open area between the pipe and the well walls when there was a blowout and a series of explosions. Oil and gas shot out of the well and up the pipe to ignition sources on the rig. When the still burning rig sank two days later, 115 of its crew had been rescued but 11 were missing and later presumed dead. Deepwater Horizon had a blowout prevention system designed to activate a blowout preventer at the well head. As a last resort, this system could direct shear rams to seal off the well by pinching the pipe closed and cutting the pipe above the cut. This did not happen. The rams may not have been able to cut though the strong pipes used in deepwater drilling. Alternatively, drillers on the rig may have failed to activate the system which was reported later to have a dead battery and to be leaking hydraulic fluid. The rig also had an automatic deadman switch designed to act as a backup to the main blowout prevention system. This also failed, perhaps due to the fact that one of its two batteries was dead. The explosions at the well site occurred less than a day after Halliburton had driven a cement plug deep down into the well to temporarily seal it. Up to this point, the heavy drilling fluid known as ‘mud’ was keeping gas and oil from exiting the well. As a general rule, mud is not removed until a sufficient period of time has been allowed for the cement plug to set. In this case it appears that, despite tests suggesting that there was gas in the well, mud was removed soon after the insertion of the cement plug. The blowout preventer at the well site was unable to stop the consequent expulsion of gas and crude. On 25 April, the US Coast Guard using underwater cameras, estimated that 5,000 b/d oil was leaking not only from the well, but also from three places on the pipe that once connected the well to the rig which now lay twisted on the ocean floor. Oil began to slowly rise to the surface. Aerial surveys by the National Oceanic and Atmospheric Administration early the following week reported that a spreading oil slick was drifting towards the Alabama and Florida coasts. Inflatable booms were only marginally successful in changing the direction of the slick, and spill response vessels were unable to skim off much of the spill due to choppy waters. The slick threatened salt marches, tidal flats, oyster beds, shrimp habitats, nesting birds, resident dolphins and sea turtles, migrating humming birds, a wildlife reserve and pristine sand beaches. It washed ashore on Louisiana’s offshore Chandeleur Islands a few days before the Gulf of Mexico’s $12bn commercial seafood industry was due to start. The US government banned fishing in federally controlled waters in the path of the spill and the state of Louisiana did the same for state-controlled waters. President Obama announced that BP will be held responsible for the costs of clean-up. In addition to injecting dispersants near the source of the several leaks, BP made several attempts to seal the well. It constructed a large dome to cover the well but soon abandoned this. A rapidly freezing mix of natural gas and water formed hydrates clogging the dome’s top opening and large accumulations of hydrates, which are lighter than water, threatened to increase the buoyancy of dome and lift it out of place. Efforts to provide heat to melt the hydrates failed. A smaller replacement dome appeared to have a better chance of success by allowing heat from the spurting oil to build up in the interior more quickly, preventing the formation of hydrates and allowing the oil, water and gas mixture to flow up the pipe. BP planned to drill into the pipe and attach a connector to draw out the oil to a waiting ship. Early in April, President Obama had mentioned the possibility of opening new sections of Gulf and other parts of US coastline to offshore drilling for the first time in nearly 30 years - this proposal has been dropped and an executive ban issued to prevent drilling in new offshore areas pending the conclusion of the investigation on the cause of spill. Congress is considering what kind of legislation will be necessary to prevent future spills. Proposals include increasing industry liability for spills and even a permanent ban on offshore drilling. One suggestion which may come to pass is splitting the MMS into two divisions. One division would handle the permitting and administration of offshore leases, and the collection of royalties from these and the other would be in charge of safety inspections. There have also been suggestions to lengthen the period for reviews of oil exploration plans from 30-90 days, and to increase the number of MMS safety inspectors which currently stands at around 60.