Deepwater Horizon/The Macondo Well, "A Hole at the Bottom of the Sea"
Deepwater horizon was a Mobile Offshore Drilling Unit (MODU) which used thrusters, computerized GPS units and manpower to monitor the floating rigs position. (8) It started as an exploration mission and proved to be a well estimating a 50 million-barrel find. The well was then plugged, so the Horizon could go in search of other promising sites. British Petroleum (BP) paid Transocean $525,000 a day to lease the Horizon Rig which cost approximately one million dollars a day to operate. BP was the largest producer of oil in the US.
The Macondo Well Inferno
"Take care of the little things. Pay attention to the stuff that doesn't quite make sense. Don't ignore those anomalies and hope they'll go away of their own volition. Respect the rules. Follow proper procedures. Don't ignore low-probability, high-consequence scenarios. Hope for the best, but plan for the worst."(9)
The Deepwater horizon, Macondo well blow out could be compared to other accidents, where lack of attention to details and a series of mistakes led to such a disaster. The fact that this accident occurred a mile below the ocean's surface made it more difficult to assess the situation let alone initiate a remedy. As oil companies moved further and further off shore, they didn't plan for the reality of a blow out or how to handle it. BP used the same hardware and skills that were meant for shallower waters. Sealing the blowout could cause an underground version that could dump even more oil into the Gulf by tapping the entire reservoir. With such a high profile and massive situation facing the company and its engineers, no one wanted to make another mistake so the oil flowed for weeks and weeks. (10)
It wasn't long before Macondo earned the name, "well from hell". (11) The first rig was damaged by a hurricane in October 2009 and Horizon took over four months later. Drilling was problematic with friable rock and gas pocketing. The original drill hole was abandoned and a new one started. Another indication that this well was a potential trouble was the excessive amount of "mud" needed as a "drilling fluid". (12) This all-purpose fluid helps the driller diagnose potential problems after having run through the well and back again. They can detect gas in the mud, which is actually acting as a counterbalance to its pressure. In the Macondo well, the mud was getting lost in the porous rock, which meant that a lot of time and money was used to make constant adjustments. As it turned out, the reason for the trouble was a non-uniform reservoir of oil. Instead of one large pool of oil, there were several layers consisting of various pressures, which resulted in the uneven utilization and distribution of the mud. It was an engineering nightmare that led to a temporary abandonment of the well. On April nineteenth, workers cemented the well with a lighter weight nitrogen-foamed cement mixture. (13)But many mistakes were made and corners cut when cementing the well. They skipped a "curing process" for the cement, which entails circulating heavy mud outside the casing before cementing. There was also a lack of centralizers used to be sure a proper seal was formed. (14) After the cementing was finished they neglected to conduct a twelve-hour test, called a cement bond log, that would confirm the integrity of the cement job. This test would have detected any gaps in the cement through an instrument that did acoustic readings. Next, a pressure test called a negative test was conducted that would allow the oil to enter the well if the cement plug was not there. If the plug is sealed properly, the oil will not pass. When the crew ran the test, the drill pipe filled with seawater and the pressure did not drop off, as it should. The closure of the pipe caused an immense pressure build up. When they repeated the inspection, the resulting pressure increased. Assuming a gauge wasn't working, they performed a second pressure test on the line connecting the rig to the blowout preventer. This test indicated no problem, even though they still had a high pressure on the drill pipe. (15)
Ironically, several executives from Transocean were visiting the rig for the purpose of safety. (16) As they operated a simulator which put them in the middle of a fake hurricane, gas emerged from the well, entered an engine room and an explosion occurred; then fire. An engineer was in the process of activating the Emergency Disconnect System when the Captain delayed him. This move would have disconnected the rig from the well, slicing the drill pipe and preventing the oil and gas from flowing up. Without knowing who was in charge in this situation, conditions deteriorated until the fire forced most of the crew to evacuate the rig. (17) The blown out well took eleven lives. (18)
Now the race was on to put out the fire and control the leak. There was concern about sealing the well and then the build up of pressure causing an "underground blowout" which would mean the escape of the entire reservoir of oil. (19) Engineers decided there was no other choice but to use a remotely operated vehicle (ROV) to install a "hot stab" into the blowout preventer, triggering it to seal the well. (20) A glitch in the plan was that Deepwater's ROV and the tools were on the burning rig. (21) They could borrow an ROV, but the fire burned on while they searched for the appropriate hot stab for Horizon's preventer. Eventually officials watched as the ROV used the hot stab to seal the well but the pressure gauge confirmed an unsuccessful attempt. (22) A second ROV ship repeated the same mission as the first without success. A third attempt to cut through a trigger pin to activate an "auto shear mechanism" was made, but the grinder could not cut the pin. After repeated tries, the pin was cut but the fire still burned. . In the meantime the rig deck was inundated with seawater and eventually collapsed and sank five thousand feet. The fire gradually subsided and the oil began to disperse. (23)
The Spill
Early reports told the public there was no spill, but the ROV confirmed a leak at the end of the drill pipe. (24) According to the National Contingency Plan spawned from the Oil Pollution Act of 1990, the polluter was responsible for cleaning up the oil with the feds supervising. The National Oceanic and Atmospheric Administration (NOAA) estimated a one thousand-barrel a day leak. So for the time being, there was a confidence that this spill would be handled without huge consequences. They felt that the
Exxon Valdez
spill left them with the experiential knowledge to effectively and efficiently clean up the spill. Skimmers were deployed and dispersants applied to the spill. (25)
By the end of April, the spill covered over 2400 square miles of the Gulf. This would call into question the initial flow rate of the spill. A computer model, developed by Oscar Garcia and based on satellite imagery, calculated that the spill was averaging over 26,000 barrels a day. NOAA on the other hand released in late April their estimates of only 5000 barrels a day. BP engineers estimated a worse case scenario of 60,000 barrels a day, but agreed that NOAA's estimate of 5000 barrels a day was more likely. (26)
At this point the ROV revealed three small leaks. With President Obama announcing to the public that the spill "could take many days to stop", it became a reality that the spill could reach and surpass the magnitude of the
Valdez
spill. As the spill spread, it reached closer towards the shores of Louisiana dealing the residents there their next disaster since hurricane Katrina. There was also the prediction of the oil getting taken by the Loop Current
and delivered to Florida beaches and potentially reaching the Gulf Stream. (27)
Seventeen days into the spill an attempt was made to lower a dome called a cofferdam over the leak to stop the flow. It too failed, rising up from the flow of the oil and then sinking to the ocean floor. (28) A new Flow Rate Technical Group now estimated the flow rates between 12,000 and 25,000 barrels a day. (29) Enter Steven Chu, Nobel Prize winner, Secretary of Energy. He called for a team of scientists with the hope of designing a creative remedy for the leak. Weeks passed with blame being passed back and forth between Chu and BP engineers. The estimates had risen to between 25,000 and 30,000 barrels a day. (30)
In June, the
Discover Enterprise
and
Q4000
started to collect 25,000 barrels a day from the blowout preventer and successfully capped in July, the well leaving a spill of 4.9 million barrels over the course of twelve weeks, while off shore drilling's future was thrown into question. (31)