Something isn't adding up here...
, the EPA monitoring station at Venice LA (about 40 miles from the leak) has found hydrogen sulfide levels of 1000 ppbv (1 ppmv). The
source is dated May 10, 2010, and gives the date of the readings as "last Thursday", which would be May 6, 2010, 16 days after the explosion.
Normal levels of H2S are on the order of a maximum of 10 ppbv - negligible.
That means that, best case, there was at that time a bubble of air that contained excessive H2S with a radius of at least 40 miles. And bear in mind
that this assumes one severely mitigating factor: The bubble had to extend farther than that; a gaseous pollutant will disperse gradually, not
suddenly at a particular distance. There would have been higher concentrations near the actual source, and the concentrations would reduce somewhat
linearly as a function of distance. So the concept of a 40-mile bubble of contamination is extremely optimistic.
But even considering a bubble of homogeneous composition contained within a 40-mile radius of the source, that bubble would contain a volume of air
equal to 1/2 the volume of a 40-mile radius sphere. 40 miles = 211,200 feet, so that gives a volume of 1.97·10^16 ft³. If one part per million of
that is H2S, that gives a volume of H2S of 1.97·10^10 ft³.
Now I am no petroleum expert, but a search for composition of natural gas led me to this little
tidbit of information
: from the chart about a third of the way down the page, it is shown that H2S is extant in natural gas in the range of
0-5%. Worst case: the H2S is one-twentieth of the natural gas that is escaping.
So if the amount if H2S released is conservatively estimated at 1.97·10^10 ft³, that means the amount of natural gas released must be a minimum of
20 times that amount, or 3.95·10^11 ft³. And this report
the amount of oil leaking to the amount of gas leaking:
Spewing from the ocean floor a mile deep is a mixture that, according to BP, is roughly half methane and other gases by mass and half petroleum
compounds, Valentine told Discovery News, and while the oil itself migrates unevenly around the Gulf in ways that are difficult to track, the behavior
of methane is more congenial to measurement.
So if the mixture is roughly 50-50, that means that a minimum of 3.95·10^11 ft³ of oil was also released in the 16 day time span between the
explosion and May 6. Averaged, that is 2.47·10^10 ft³ of oil and 2.47·10^10 ft³ of gas per day at the surface. Of course, that volume is decreased
as pressure increases (like at the leak) and when temperature is lowered (like at the leak).
Using the Ideal Gas Law
, volume is proportional to pressure divided by temperature. If we take
an average summer's day conditions in LA of 95°F and 15psi, and conditions a mile below the water at 32°F and
, that gives us a ration of 180 to 1... meaning
that 1 ft³ coming out of the well will become 180 ft³ at the surface. That drops the amount of gas to 1.37·10^8 ft³, and the amount of oil to the
A barrel of oil is equivalent to 5.61 ft³*. So that gives us a minimum oil leakage rate of 2.45·10^8 bbl of oil per day. Everyone get that?
Almost 25 MILLION bbl of oil per day!
At that rate, in the approximately 60 days of leakage, that would be 1.47·10^9 bbl of oil, or 6.16·10^10 gallons of oil that should have leaked out
into the Gulf of Mexico. The volume of the Gulf
is estimated to be about 660 quadrillion
(6.6·10^17) gallons, meaning that the overall minimum concentration in the Gulf should be at a minimum of 93.4 ppbv, or 0.00000934%.
That looks about right to me, based on the areas being closed to fishing. Of course, that is just simple observation with no real numbers to back it
So what is happening here? Is there really 25 MILLION barrels of oil leaking out every day (1000 times the highest estimates I have heard thus far)
and everyone involved is simply underestimating that much? Is there actually more gas than oil leaking out? Does the gas contain an abnormally high
amount of H2S? Is someone using sulfur-based dispersants? If the oil/gas really is coming out that fast, is it from the main leak, or is the whole
These numbers don't jive with the official line. Where is the sulfur coming from?
BP: "Beyond Propaganda"?
* 1 bbl = 42 gal
; 1 gal = 231
; 1 ft³ = 12³ in³ = 1728 in³
1 bbl = 42·231/1728 = 5.61 ft³