Saturday, June 5, 2010

Math…and the Gulf Oil Spill

Without a doubt, the oil spilling into the Gulf of Mexico is a regrettable event – dooming various parts of the Gulf to loss of shrimping, oystering, tourism and pleasure – at least for a time. I would never say that the spill is a non-issue, nor would I belittle any effort to cap the pipe on the ocean floor. Every effort needs to be pursued to get it under control. And the loss of life of the eleven men on the Deepwater Horizon rig is a tragedy as well. My heart goes out to their families.

I don’t have cable TV or satellite channels coming into my home, but there are a lot of TV’s at my place of work which do. And the image seems to constantly be that of the BP cameras trained on the broken and oft-repaired pipe at the bottom of the Gulf, spewing oil into the ocean. Given the amount of attention placed on that camera shot, many might come to the conclusion that the Gulf is filling up with oil.

So, I decided to do some math around the spill and put it into perspective. Here are some facts:

· The federal government estimates that the total leakage from the pipe to-date has been somewhere between 22 million and 47 million gallons. For purposes of my exercise, I will use the largest number – 47 million gallons.

· The oil has been spilling from the pipe since the rig explosion on April 20, 2010 –a total of 46 days.

· Rounded slightly, that gives us a daily spill rate of 1 million gallons

Now, just how big is a million gallons? Well, a gallon is equal to 0.133680556 cubic feet. So, a million gallons takes up 133,680 cubic feet. Taking the cube root of that number will give you the dimension of a side of that million-gallon cube – 51 feet on all three sides. A typical tractor trailer that you see hauling goods on the interstate is 53 feet long, by 8.5 feet wide by 9.25 feet tall – that’s 4,167 cubic feet. That amount of space is capable of holding 31,172 gallons of oil (4,167 cubic feet divided by 0.13368 cubic feet per gallon). Dividing a million gallons by this figure tells us that the volume of spill coming from the broken well is equal to about 32 tractor trailers each day.

Thirty-two big-rig trailers full of oil seems like a lot. But let’s put it into perspective. The Environmental Protection Agency tells us that the Gulf of Mexico holds 643 quadrillion gallons of liquid. Spelled out, that is 643,000,000,000,000,000 gallons of salt water. Dividing by 31,172 gallons, this tells us that the Gulf of Mexico is capable of holding 20,627,486,205,569 tractor trailers full of liquid. That’s 20.6 trillion trailers.

So – in a total volume of 20.6 trillion tractor trailers, we are displacing 32 trailers full of oil each day. Assuming the oil field is infinite (obviously not a valid assumption, but stick with me), how many days would it take to completely displace all of the water in the Gulf? Simply divide the two numbers, and you get 644,608,943,924 days. That’s 644 billion days, which when divided by 365 yields 1,766,051,901 years.

So, at the current spill rate, we will fill the Gulf of Mexico with oil in approximately 1.76 billion years.

Let’s put it another way – in a visual. It’s estimated that about 30 million grains of sand fit into a one-gallon bucket (this is obviously very dependent on the type of sand). Assume that one of those grains of sand represents the 32 tractor trailers (1 million gallons) of oil being spilled each day. How many grains of sand represent the rest of the Gulf of Mexico? Simple division – 20.6 trillion divided by 32 – equals 644 billion grains of sand. How many gallon buckets of sand is that? Again, divide 644,000,000,000 by 30 million – and you get 21,467 one-gallon buckets of sand. So, if you can picture lining up 21,467 gallon buckets of sand (or 4,293 five-gallon buckets) in a parking lot, the relative volume of oil being spilled into the gulf each day is equal to one grain of sand.

Unfortunately, all of that oil has a tendency to spread upward and toward the edges of wherever it travels. This tends to make moot any volumetric comparisons and analogies – because the oil is finding its way to the exact places that we don’t want it – beaches and fishing grounds. If oil were heavier than water, this whole event would be a non-issue – we’d have the equivalent of a tiny percentage of the Gulf being taken up with a small pool of oil at the bottom.

Of course, BP has not yet taken action on my spill-prevention suggestion – to stuff the Obamacare bill into the end of the oil pipe. That way, we could take care of two problems at once…


For an extremely interesting time-lapse-from-space video of the Gulf spill, via NASA satellites, visit this site..

1 comment:

Brad Richardson said...

Hey Alan,
Thanks for crunching the numbers. That was very enlightening. This just looks like another case of the press blowing things out of proportion. I'll even go a step further and actually defend Obama (who would've thunk that?). I don't get all these people demanding that Obama and the feds come swoop in and save the day. I mean, come on...isn't BP financially motivated to fix this as millions of gallons of their product wash away. What I thought was really funny was that James Cameron offered up his expertise for the situation and was turned away. Now I haven't seen Avatar but I can imagine that he'd have some great ideas for "healing" the Earth.