Today’s top headlines delivered to you daily.

# Q&A: Putting the gulf oil spill in perspective on land

Calculating oil spill's reach

Let's assume the gulf oil disaster has released 100 million gallons of oil. Can you tell us how much land that would cover up to a depth of 1 inch? Also, what is the conversion factor between barrels and gallons?

That much oil, assuming no evaporation or absorption into the ground, would not cover as much ground as you might think.

For math help we turned to Howard Perlman, a hydrologist with the U.S. Geological Survey. He, in turn, pointed us to a nifty calculator at ga.water.usgs.gov/edu/sc2.html.

Perlman walked us through it:

"First, make sure the 'Rainfall' box says '1 inch.'

"I can use trial and error until I get to 100 million gallons. I try the square miles box and enter 1. The resulting page tell me 17,378,560 gallons.

"So 100 million divided by the 17.38 million gives us about 5.75. If I enter that into my square miles box it should come up with about 100 million gallons.

"Well, my box will only let me enter a number to the tenths column, so I entered 5.7 into square miles and yes, it says 99,057,792 gallons.

"So I would say that 100 million gallons would cover 5.75 square miles to a depth of 1 inch — of water, that is. And it should not make a difference if it was oil."

Over a grid of St. Petersburg, that square mileage would fill an area approximately from Tampa Bay to 49th St. (about 5 miles) between 22nd Avenue N and Fifth Avenue N (a little over a mile).

There are 42 U.S. gallons in a barrel of oil, according to the Energy Information Administration. Only 19 or 20 gallons are used for gasoline; the rest goes to distillate and residual fuel oils, jet fuel and other products.

Turning a pesky plant into gas

Has anyone done research into using kudzu for biofuel?

Most efforts today are aimed at trying to kill kudzu, an invasive vinelike weed that has cost billions of dollars in lost crops. However, it has potential as an ingredient for biofuels.

A 2008 study concluded that, under certain conditions, kudzu could produce about 400 liters of ethanol per acre, on par with an acre of corn. The study was conducted by the University of Toronto and the U.S. Agriculture Department's Agriculture Research Service.

The next step is a large-scale project that could prove using kudzu to make ethanol is economically feasible, University of Toronto Professor Rowan Sage said.

That has yet to occur. One reason could be that investment in many areas of alternative energy virtually dried up as the recession took hold and gas prices fell.

Agrogas, which is based in Cleveland, Tenn., is working to raise capital to finance a project to prove the viability of commercial production of ethanol using kudzu. It already has operated test vehicles using limited quantities.

Q&A: Putting the gulf oil spill in perspective on land 07/01/10 [Last modified: Wednesday, June 30, 2010 2:59pm]
Photo reprints | Article reprints

1. ## Editorial: Genshaft right to oust USF St. Petersburg leader

Editorials

In times of crisis, leaders cannot abandon ship and be unclear about their whereabouts. That is essentially what the leader of the University of South Florida St. Petersburg did with Hurricane Irma headed this way. Sophia Wisniewska's actions fell short of what should be expected from an experienced administrator …

2. ## Duke Energy Florida president answers questions about utility's response to Irma

Hurricanes

ST. PETERSBURG — After more than a week since Hurricane Irma knocked out power to millions of Floridians, Duke Energy announced it will finish its restoration efforts Tuesday.

3. ## Leaves, mountains, ice cream and cheese: What's not to like in Burlington, Vt.?

Travel

If I loved Burlington, Vt., during a visit with my daughter when the high was 37 degrees, I feel completely comfortable recommending the city as a great destination for fall, when it's considered one of the top leaf-watching spots in the world.

4. ## Puerto Ricans in Tampa Bay wait with dread as Hurricane Maria approaches island

Hurricanes

TAMPA — As Hurricane Maria swirled in the Atlantic Ocean, Sarykarmen Rivera got a phone call from her parents in Puerto Rico. They had an ominous message.

5. ## Early estimates peg Hurricane Irma damage at as much as \$65B

Banking

The damage totals from Hurricane Irma are still being tallied, but early numbers are in: As of Tuesday, the storm is estimated to have caused between \$42.5 billion and \$65 billion of damage. That's according to a Tuesday release by Irvine, Calif.-based analytics company CoreLogic.

• 490 First Avenue South
• St. Petersburg, FL 33701
• 727-893-8111