Now that the oil is no longer flowing into the Gulf of Mexico questions still remain as to why this major disaster was not averted given the safety measures and regulations put in place to prevent this exact situation. In the near future BP plans to bring the BOP, or Blowout Preventer, to the surface to determine why it failed. The main function of a BOP is to shut off any flow from a well and sever any drill string or pipe inside the well to prevent any fluid or gas escaping uncontrollably, known as a blowout. The BOP is also capable of separating so the vessel can move away from the site while leaving the capping function on the well. Unfortunately this function did not work either.
Transocean, the owner of the Deepwater Horizon and responsible for the operation and maintenance of the BOP, appears to have ignored problems and avoided federally required maintenance. According to a recent article in The Times- Picayune, Transocean officials have acknowledged that the BOP had several leaks and mandatory recertifications were ignored. The severity of the leaks are still being debated, and the truth will probably not be determined until the BOP is brought to the surface.
As for the regulations, the federal agency known as MMS required BOPs to be recertified every three years with exceptions to five. The recertification of a BOP requires complete disassembly and can take as long as 90 days. This may not seem very long but when an average rate for a drilling vessel runs about $250,000 a day just for the rig itself, a 90 day downtime could result in $22.5 million in lost revenue for Transocean. According to a Transocean subsea superintendent, the company felt that the regulation was a recommendation and that monitoring the BOP for issues would suffice.
There are backup functions on BOPs and the one on the Deepwater Horizon was capable of being functioned at depth, by remotely operated vehicles or ROV’s. The ROV would plug a hydraulic hose into a port on the BOP and function it exactly like the controls on the surface. When this procedure was attempted it was discovered that the ports had been routed to test valves rather than the ones designed to function the rams that would shut off the well. Apparently Transocean had decided that in order to save time and money they would use test valves to verify the BOP was functioning properly while drilling operations were underway. Normally, to test the BOP, the drill string must be clear so the rams can be fully closed and tested. The test rams are for test purposes only and designed to hold pressure from above and not below. These test rams were installed sometime between 2004 and 2005 and Transocean claims BP was informed of the changes. These changes may have not directly resulted in the BOP’s failure but rather it may have been a simple mistake with grave consequences that actually caused the worst environmental disaster in U.S. history.
At some point Transocean had reconfigured the plumbing on the BOP stack without the consent or knowledge of any other party. Normally this would not be an issue, but it was here, where critical mistakes were made. Apparently while attempting to shut the BOP with the ROV it became apparent to the Transocean and BP officials coordinating the operation that the plumbing had been done wrong. One official was quoted as saying, “When I heard the news I lost all faith in this BOP stack plumbing.”
Although the final investigation as to the full cause of the BOP failure may not be determined for a few months, the sad truth is this whole disaster may have been avoided had Transocean properly tested the BOP while it was on deck, and not relied on test valves to ensure the BOP was plumbed correctly. Every company has to find ways to remain competitive and cut costs but there must also be checks in place when it comes to safety. Had they attempted to test the BOP as if it were a real emergency at any time before the accident, this tragedy most likely would have been avoided.
Source: The Times-Picayune, August 26, 2010