How many gallons of oil have spilled into the gulf as of June 9?

Answer 1

The spilled volume numbers as of June 9, given here are subject to revision. The Joint Command has stated that the task force is busy updating their numbers.

What I can say without ambiguity, is that oil has been flowing into the Gulf for 11 days in April, 31 days in May and 9 days in June, or 51 days. Also, there are 42 gallons in a barrel.

So, total rate = 51 x average rate. Yet, the average rate has been changing as BP has been fighting this blow out. So, I don't have any official tally and as far as I can tell, there isn't one at present. The media seems to prefer to use the very largest number they can find, to justify the headline, up to X million gallons have been spilled.

Previously, there was a range given by the Task Force using one method, as 12,000 to 19,000 barrels per day, and a range of 12,000 to 25,000 barrels per day (bopd) using a second method. Now, the latest rate from the lower marine riser is around 16,000 barrels per day, so, the upper end of these ranges seems more likely.

So, if I assume 20,000 bopd are coming out, 51 x 20,000 or 1020 thousand barrels (MBBL) may have come out. However, there are some notable deductions, because the insert tool was capturing some of the oil and now the marine riser appears to have capture a lot of the oil. Finally, it was estimated that the cutting of the marine riser increase the rate by 20%. So, if I use a rate of 15,000 for 30 days, 10,000 for 15 days, and 4,000 for 6 days, might be a better guess, or (450 + 150 + 24) = 624 MBBL. A lot of this oil has been evaporated, burned or skimmed, so the surface oil may be considerably less than 624 MBBL. Some estimates have been that 40% may eventually evaporate, bringing the total to 374 MBBL or 15.7 million gallons.

So, final answer, subject to change, is 42 million gallons out of the well, but 16 million gallons taking into consideration evaporation and capture.