CORYDON, Iowa (AP) — The hills of southern Iowa bear the scars of America's push for green energy: The brown gashes where rain has washed away the soil. The polluted streams that dump fertilizer into the water supply.
Even the cemetery that disappeared like an apparition into a cornfield.
It wasn't supposed to be this way.
With the Iowa political caucuses on the horizon in 2007, presidential candidate Barack Obama made homegrown corn a centerpiece of his plan to slow global warming. And when President George W. Bush signed a law that year requiring oil companies to add billions of gallons of ethanol to their gasoline each year, Bush predicted it would make the country "stronger, cleaner and more secure."
But the ethanol era has proven far more damaging to the environment than politicians promised and much worse than the government admits today.
As farmers rushed to find new places to plant corn, they wiped out millions of acres of conservation land, destroyed habitat and polluted water supplies, an Associated Press investigation found.
Five million acres of land set aside for conservation — more than Yellowstone, Everglades and Yosemite National Parks combined — have vanished on Obama's watch.
Landowners filled in wetlands. They plowed into pristine prairies, releasing carbon dioxide that had been locked in the soil.
Sprayers pumped out billions of pounds of fertilizer, some of which seeped into drinking water, contaminated rivers and worsened the huge dead zone in the Gulf of Mexico where marine life can't survive.
The consequences are so severe that environmentalists and many scientists have now rejected corn-based ethanol as bad environmental policy. But the Obama administration stands by it, highlighting its benefits to the farming industry rather than any negative impact.
Farmers planted 15 million more acres of corn last year than before the ethanol boom, and the effects are visible in places like south central Iowa.
The hilly, once-grassy landscape is made up of fragile soil that, unlike the earth in the rest of the state, is poorly suited for corn. Nevertheless, it has yielded to America's demand for it.
"They're raping the land," said Bill Alley, a member of the board of supervisors in Wayne County, which now bears little resemblance to the rolling cow pastures shown in postcards sold at a Corydon pharmacy.
All energy comes at a cost. The environmental consequences of drilling for oil and natural gas are well documented and severe. But in the president's push to reduce greenhouse gases and curtail global warming, his administration has allowed so-called green energy to do not-so-green things.
In some cases, such as its decision to allow wind farms to kill eagles, the administration accepts environmental costs because they pale in comparison to the havoc it believes global warming could ultimately cause.
Ethanol is different.
The government's predictions of the benefits have proven so inaccurate that independent scientists question whether it will ever achieve its central environmental goal: reducing greenhouse gases. That makes the hidden costs even more significant.
"This is an ecological disaster," said Craig Cox with the Environmental Working Group, a natural ally of the president that, like others, now finds itself at odds with the White House.
But it's a cost the administration is willing to accept. It believes supporting corn ethanol is the best way to encourage the development of biofuels that will someday be cleaner and greener than today's. Pulling the plug on corn ethanol, officials fear, might mean killing any hope of these next-generation fuels.
"That is what you give up if you don't recognize that renewable fuels have some place here," EPA administrator Gina McCarthy said in a recent interview with AP. "All renewable fuels are not corn ethanol."
Still, corn supplies the overwhelming majority of ethanol in the United States, and the administration is loath to discuss the environmental consequences.
"It just caught us completely off guard," said Doug Davenport, a Department of Agriculture official who encourages southern Iowa farmers to use conservation practices on their land. Despite those efforts, Davenport said he was surprised at how much fragile, erodible land was turned into corn fields.
Shortly after Davenport spoke to The Associated Press, he got an email ordering him to stop talking.
"We just want to have a consistent message on the topic," an Agriculture Department spokesman in Iowa said.
That consistent message was laid out by Agriculture Secretary Tom Vilsack, who spoke to ethanol lobbyists on Capitol Hill recently and said ethanol was good for business.
"We are committed to this industry because we understand its benefits," he said. "We understand it's about farm income. It's about stabilizing and maintaining farm income which is at record levels."
The numbers behind the ethanol mandate have become so unworkable that, for the first time, the EPA is soon expected to reduce the amount of ethanol required to be added to the gasoline supply. An unusual coalition of big oil companies, environmental groups and food companies is pushing the government to go even further and reconsider the entire ethanol program.
The ethanol industry is fighting hard against that effort. Industry spokesman Brooke Coleman dismissed this story as "propaganda on a page." An industry blog in Minnesota said the AP had succumbed "to Big Oil's deep pockets and powerful influence."
To understand how America got to an environmental policy with such harmful environmental consequences, it's helpful to start in a field in Iowa.
Leroy Perkins, a white-haired, 66-year-old farmer in denim overalls, stands surrounded by waist-high grass and clover. He owns 91 acres like this, all hilly and erodible, that he set aside for conservation years ago.
Soon, he will have a decision to make: keep the land as it is or, like many of his neighbors, plow it down and plant corn or soybeans, the major sources of biofuel in the United States.
"I'd like to keep it in," he said. "This is what southern Iowa's for: raising grass."
For decades, the government's Conservation Reserve Program has paid farmers to stop farming environmentally sensitive land. Grassy fields naturally convert carbon dioxide into oxygen, which helps combat global warming. Plus, their deep root systems prevent topsoil from washing away.
For Perkins and his farmer neighbors in Wayne County, keeping farmland in conservation wasn't just good stewardship. It made financial sense.
A decade ago, Washington paid them about $70 an acre each year to leave their farmland idle. With corn selling for about $2 per bushel (56 pounds) back then, farming the hilly, inferior soil was bad business.
Many opted into the conservation program. Others kept their grasslands for cow pastures.
Lately, though, the math has changed.
"I'm coming to the point where financially, it's not feasible," Perkins said.
The change began in 2007, when Congress passed a law requiring oil companies to blend billions of gallons of ethanol into gasoline.
Oil prices were high. Oil imports were rising quickly. The legislation had the strong backing of the presidential candidate who was the junior senator from neighboring Illinois, the nation's second-largest corn producer.
"If we're going to get serious about investing in our energy future, we must give our family farmers and local ethanol producers a fair shot at success," Obama said then.
The Democratic primary field was crowded, and if he didn't win the Iowa caucuses the road to the nomination would be difficult. His strong support for ethanol set him apart.
"Any time we could talk about support for ethanol, we did," said Mitch Stewart, the battleground states director for Obama's 2008 campaign. "It's how we would lead a lot of discussions."
President Bush signed the bill that December.
It would fall on the next president to figure out how to make it work.
President Obama's team at the EPA was sour on the ethanol mandate from the start.
As a way to reduce global warming, they knew corn ethanol was a dubious proposition. Corn demands fertilizer, which is made using natural gas. What's worse, ethanol factories typically burn coal or gas, both of which release carbon dioxide.
Then there was the land conversion, the most controversial and difficult-to-predict outcome.
Digging up grassland releases greenhouse gases, so environmentalists are skeptical of any program that encourages planting more corn.
"I don't remember anybody having great passion for this," said Bob Sussman, who served on Obama's transition team and recently retired as EPA's senior policy counsel. "I don't have a lot of personal enthusiasm for the program."
At the White House and the Department of Agriculture, though, there was plenty of enthusiasm.
One of Obama's senior advisers, Pete Rouse, had worked on ethanol issues as chief of staff to Sen. Tom Daschle of South Dakota, a major ethanol booster and now chair of the DuPont Advisory Committee on Agriculture Innovation and Productivity.
Another Obama adviser at the time, Heather Zichal, grew up in northeast Iowa — as a child, she was crowned "sweet corn princess" — and was one of the Obama campaign's leading voices on ethanol in her home state.
The administration had no greater corn ethanol advocate than Vilsack, the former Iowa governor.
"Tom understands that the solution to our energy crisis will be found not in oil fields abroad but in our farm fields here at home," Obama said in 2008. "That is the kind of leader I want in my Cabinet."
Writing the regulations to implement the ethanol mandate was among the administration's first major environmental undertakings. Industry and environmental groups watched closely.
The EPA's experts determined that the mandate would increase demand for corn and encourage farmers to plow more land. Considering those factors, they said, corn ethanol was only slightly better than gasoline when it came to carbon dioxide emissions.
Sixteen percent better, to be exact. And not in the short term. Only by 2022.
By law, though, biofuels were supposed to be at least 20 percent greener than gasoline.
From a legal standpoint, the results didn't matter. Congress exempted existing coal- and gas-burning ethanol plants from meeting this standard.
But as a policy and public relations issue, it was a real problem. The biofuel-friendly Obama administration was undermining the industry's major selling point: that it was much greener than gasoline.
So the ethanol industry was livid. Lobbyists flooded the EPA with criticism, challenging the government's methods and conclusions.
The EPA's conclusion was based on a model. Plug in some assumed figures — the price of corn, the number of acres planted, how much corn would grow per acre — and the model would spit out a number.
To get past 20 percent, the EPA needed to change its assumptions.
The most important of those assumptions was called the yield, a measure of how much corn could be produced on an acre of land. The higher the yield, the easier it would be for farmers to meet the growing demand without plowing new farmland, which counted against ethanol in the greenhouse gas equation.
Corn yields have inched steadily upward over the years as farms have become more efficient. The government's first ethanol model assumed that trend would continue, rising from 150 bushels per acre to about 180 by the year 2022.
Agriculture companies like Monsanto Co. and DuPont Pioneer, which stood to make millions off an ethanol boom, told the government those numbers were too low.
They predicted that genetically modified seeds — which they produce — would send yields skyrocketing. With higher yields, farmers could produce more corn on less land, reducing the environmental effects.
Documents show the White House budget office also suggested the EPA raise its yield assumptions.
When the final rule came out, the EPA and Agriculture officials added a new "high yield case scenario" that assumed 230 bushels per acre.
The flaw in those assumptions, independent scientists knew, was that a big increase in corn prices would encourage people to farm in less hospitable areas like Wayne County, which could never produce such large yields.
But the EPA's model assumed only a tiny increase in corn prices.
"You adjust a few numbers to get it where you want it, and then you call it good," said Adam Liska, assistant professor of biological systems engineering at the University of Nebraska. He supports ethanol, even with its environmental trade-offs.