In his inaugural address, President Obama promised "to restore science to its rightful place." Last week, in arguably one of the toughest tests of that pledge yet, the Environmental Protection Agency proposed new rules for calculating greenhouse gas emissions from ethanol. [Read more about Obama's commitment to science]
The underlying question: Does ethanol help or hurt the environment? In 2007, when Congress passed the law that lit up the U.S. biofuel industry by mandating the production of 36 billion gallons of ethanol annually by 2022, it also said that corn-based ethanol's greenhouse gas emissions must be 20 percent lower than gasoline's. [See a photo gallery of building a green home]
But, as the EPA has learned, calculating those values isn't easy. One of the biggest sources of debate has been over changes in land use, particularly abroad. If corn is taken out of the food supply to make biofuel, global food prices can rise, which can prompt farmers in other countries to clear forests for new crops. And that releases CO 2 .
Many researchers say the EPA's analyses must count these emissions; biofuel makers argue that the scientific understanding of how to calculate them is still poor.
Offering one of the first looks at how the administration intends to navigate tough scientific debates, EPA Administrator Lisa Jackson tried to strike something of a middle ground as the proposal was unveiled. Yes, she said, land-use changes should be considered, because that's what the scientific community has recommended. But in a nod to biofuel makers, the EPA also admitted it's not totally comfortable with the "best science available." [See more of Obama's top advisers]
As the EPA's 600-page proposal explains, the "best science available" relies heavily on sophisticated computer models that try to account for everything from land changes to commodity markets. In the EPA's proposal, it chose to combine at least six separate models, as well as satellite imagery documenting global land-use changes, to try to paint a complete picture of biofuel emissions.
But because this sort of approach is so complicated and has no real precedent, Jackson is also calling for a special "peer review." The EPA is currently assembling four panels, each with five outside experts, to examine the agency's concerns about its proposal. [Interactive: Creative Gasoline Alternatives]
Within the biofuel industry, which has long decried these models, the immediate reaction was mixed. "EPA is trying to put its best foot forward," Bob Dineen, president of the Renewable Fuels Association, says. "There is a great deal of uncertainty, which is why the administration wisely chose to subject those international effects to peer review."
In Congress, however, tempers flared. "Why would you rush to judgment?" charged GOP Rep. Bob Goodlatte of Virginia, regarding the rule. "We are not getting a look into how you came up with this novel methodology." In response, the EPA reminded the members of Congress that its proposal is just that: a proposal, not a final rule, subject to feedback and review.
They can expect a lot of it. Already, several perturbed members of Congress have called for tripling the public comment period for the proposal, from 60 to 180 days.