BOB GARFIELD: From WNYC in New York, this is NPR's On the Media. I'm Bob Garfield.

BROOKE GLADSTONE: And I'm Brooke Gladstone. This week, a House committee held public hearings on the BP oil disaster, where BP CEO Tony Hayward underwent a grilling. For weeks, both legislators and experts on cable news have tried to put the mounting disaster in perspective by making comparisons to the size of the Exxon Valdez spill in 1989.

FEMALE CORRESPONDENT: Twenty years ago, the Exxon Valdez spilled 11 million gallons in the water there, and fishermen say they're still healing that…

MALE CORRESPONDENT: To put that in perspective for you, the Exxon Valdez spill dumped 11 million gallons of oil…

MALE CORRESPONDENT: It was tremendous destructive catastrophe for Alaska, and it was only 11 million gallons of oil.

BROOKE GLADSTONE: But where did that figure, 11 million gallons, come from? Many people, including Riki Ott, a marine toxicologist, author and former commercial fisher, argues that 11 million was Exxon’s very early estimate and not the actual amount. Ott, who was in Alaska during the Exxon Valdez spill, says it was a dubious figure from the start.

RIKI OTT: Right off the bat, day one, uh, when I was in Cordova flying over to Valdez, we heard that there was a low-end estimate of 10.4 million gallons and a high end estimate of 38 million gallons. And the next day it was nudged up to 10.8 million gallons, and the media just captured that number. Already, 10.8 million gallons was horrific. It was the biggest oil spill in our nation’s history. It was big enough for the media.

BROOKE GLADSTONE: Are you saying that the media simply ignored the high end estimate, or Exxon stopped repeating it?

RIKI OTT: Exxon never said it in a press conference. Just when the media started to ask questions, where did that 10.8 million gallons come from, has it been independently verified, Frank Iarossi, the owner of Exxon Shipping, at a press conference said, alcohol may be involved. And I kid you not, I witnessed the entire international media just switch tracks, and that was how we got 10.8 million gallons, rounded up to 11. A couple years later, when I saw the movie Wag the Dog, I saw that scene where the president was just about to get nailed, and a plant in the audience says, well, what about the bombs in Albania? And the whole media switched to bombs in Albania. And I rose up out of my seat, and I said, that is how we got 11 million gallons. And my two friends each grabbed a wrist and pulled me back down-

[BROOKE LAUGHS] - into my chair. And I just swore that I would never forget 38 million gallons.

BROOKE GLADSTONE: So you’re essentially saying that the media have the attention span of a puppy. In other words, they ask a question and then uh the uh Exxon Valdez managers go, look, a squirrel, and then [LAUGHS] they're off and running and they forgot what they asked.

RIKI OTT: That’s pretty much exactly what happened.

BROOKE GLADSTONE: Did we ever find out how big the spill really was? There was one person who said all you have to do is measure what’s left in the Valdez and then you can figure out how much spilled. And the Valdez was supposed to hold something like 53 million gallons, right?

RIKI OTT: The State of Alaska went and hired independent surveyors because they were preparing for a lawsuit. This was a secret investigation. The code word for it was “Ace.” Each of the two independent surveyors tracked the amount of water that offloaded from Exxon Valdez, which amounted to around 19 million gallons. We have to remember that 8 of 11 cargo holds were ripped wide open. There was a 21-foot tide going in and out twice a day, and it just acted like a washing machine. So if you add 19 million gallons of water in with the 11 million gallons of oil that we know spilled, you actually end up with closer to 30 million gallons. And that’s what the two surveyors estimated spilled, between 30 to 35 million gallons.

BROOKE GLADSTONE: So why is the 11-million number still quoted everywhere? Why isn't it now regarded as disputed?

RIKI OTT: When the data popped out, the secret investigation popped out in public four years later it was no longer news. And it’s extremely unfortunate, because we did write legislation at the federal level and at the State of Alaska to protect us from an Exxon Valdez-sized oil spill, which means that we are underprotected by three times.

BROOKE GLADSTONE: Do you think the media have been smarter when it comes to the Gulf Oil leak? Have we seen some progress then?

RIKI OTT: No, I'm sorry to say, because all the numbers are repeated that are given by BP. There’s no demand by the media to say, where’s the independent monitoring? Our government didn't even ask for it. What I thought was hilarious was when BP actually started uh, claiming that it was recovering oil, and suddenly the recovery numbers were greater than the spill numbers, so the next thing you know, the spill numbers had to jump up. But the media still is not asking BP the question, how much of what you’re recovering is water.

BROOKE GLADSTONE: So what is the lesson here for reporters?

RIKI OTT: The minute we have an oil spill, assume that it’s going to be underreported on the - how much spilled and overreported on how much was recovered. And the reporters should be framing questions for the American public, why are we taking the spiller’s information without questioning it at all, why isn't the federal government out there, why aren't the universities out there? We know how to get accurate information. We should be monitoring everything the spiller does.

BROOKE GLADSTONE: Are you sure that that information is accessible? Can the government and academia and the experts that you refer to really go down there and uh, get the information that is available to the oil companies?

RIKI OTT: It’s not a matter of going down there. BP released to the public, that underwater flow that we keep seeing, that video, that was not high definition. That was very low quality. And it turns out BP all along had a high definition videocamera down there. They just didn't release it to the public.

BROOKE GLADSTONE: And if experts had been able to see the real flow in detail, they would have been able to estimate.

RIKI OTT: Yes, because that’s what they're doing now.

BROOKE GLADSTONE: Riki, thank you so much.

RIKI OTT: Thank you very much, Brooke.

BROOKE GLADSTONE: Riki Ott is the author of Not One Drop: Promises, Betrayal and Courage in the Wake of the Exxon Valdez Oil Spill.

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