The Gulf Oil Spill: April 2010, Deepwater Horizon, BP

1. The Gulf Oil Spill: April 2010, Deepwater Horizon, BP Whose to Blame as well as a reflection of the science literacy problem in the US

2. Deep Water Drilling: The Dangers of High pressure

3. Geometry of the BOP

4. How an Oil Well Works The oil entering at the bottom requires an internal pressure source to push it to the top – this is usually supplied by associated gas deposit

5. Simple Physics • Without any additional source of pressure oil by itself will not be squeezed up the tube. Thus crude oil without an internal pressure sure is usually a Dry Well • The deeper you drill the higher the internal pressure you likely to tap. This is why you need a pressure regulator a.k.a The Blow Out Preventer (BOP) rated at 15,000 PSI

6. This is what is known prior to the incident 1. The BOP is located at the bottom of the Gulf of Mexico so there is 5000 feet of water on top of it. The BOP is rated up to 15,000 PSI and is connect to a 21 inch diameter pipe. • Deep Reservoir Pressure was estimated by Coast Guard to be 8000 PSI – so no problem in principle 3. Geological data suggested that average reservoir pressures in these deep marine pockets could be 20,000 – 40,000 psi. 20,000 PSI will give you a flow rate of 50,000 barrels a day for a 21 inch diameter pipe. It will turn out that the diameter of the pipe becomes “unknown”. 4. Before the accident the BP horizon was producing 10-15,000 barrels a day suggesting pressures of 5000-8000 PSI had been tapped,

7. Then This Happened

8. Three important physical parameters of the situation The source of the outflow is via some severed pipe that is located 5000 feet below water. This means there is a hydraulic head pressure on the top of pipe which would tend to suppress any outflow (and drive ocean water into the pipe)  The failure of the BOP directly shows that the internal pressure driving the flow could be as high as 15,000 ps This pipe diameter confusion: The outflow is coming from some inner diameter core that is embedded in the casing which has a known outside diameter of 21-inches. 

9. Why 1000 BPD is Bullshit • BP initially announces the leak rate to be 1000 BPD • 6 household bathtubs equivalent • 1000 BPD completely suppressed by the 5000 feet of water on top of the pipe • Remember, initial pressure estimate by CG was 8,000 psi. Mud is like crude oil. A 7500 PSI mud pump through a 9 inch pipe is 60,000 BPD •  So how is that if you effectively cut the oil pipe in two, which was producing 10-20,000 bpd the subsequent leakage rate is now only 1,000 bpd?

10. The “Duct Tape” Solution If your using your garden hose with a nozzle at full pressure and Descartes Evil Genius comes a long and cuts your hose in two, then water is still gushing out of the severed hose. If instead, the Evil Genius just pokes your hose then the water leaking out of the whole is not very much – indeed you can likely duct tape it. The 1000 BPD figure suggests a duct tape solution as the initial governmental response, which was used, and all attempts to initially patch the leak, failed.

11. The fact that BP got away for at least a week by stating a figure of 1000 barrels a day is a sad testimony to the science illiteracy of this country and especially congress! Thus, simple considerations of likely internal flow pressure and pipe diameter lead to estimates that are at least an order of magnitude larger than 1000 bpd and some estimates made in this manner do come close to the figures determined a full two months later. A "duct tape" solution will clearly not work and this could have been known at the time. Balllon Boy Physics

12. 5000 BPD a Week Later - NOAA Other Analysis leads to 12,000 BPD; BP will insist 5000 BPD is the correct scientific answer

13. Flow rate estimates from particle velocity measurements This video data is not made publically available until May 12, 3 weeks after the incident; Scientists looking at the video immediate said, the flow must be much larger than 5000 BPD May 27: Plume Modeling Team  12- 19,000 BPD One week later: 25-30,000 BPD Two weeks later: 35,000 – 60,000 BPD  Gee isn’t that a lot bigger than 1000?

14. Velocity based flow estimate • Diameter of pipe is 21 inches cross section is .2 square meters • Volume flow rate is then 1 m/sec * .2 = .2 cubic meters per second • .2 * 3600 seconds per hour = 720 cubic meters per hour = 720,000 liters/hour • One bbl = 159 liters. Thus 720,000/159 = 4500 barrels/hour (in round numbers) • 4500 x 24 = 108,000 barrels per day  100 times worse than the initial estimate 