On Earth Day, Bush Cabinet members defended the president's environmental policies as a measured approach that balances the need for clean air and water with demands for energy and other natural resources.

"We have made a number of decisions that are very pro-environment, but unfortunately they get overlooked when there's something that people can challenge," Christie Whitman, the Environmental Protection Administration chief, said Sunday.

"I would hope that we look at the total picture. Are we making the air cleaner, the water purer, are we better protecting the land?" she said on CBS' Face the Nation.

Environmental groups and some Democrats criticize Bush for rescinding several Clinton administration initiatives. They also say Bush is pushing for oil drilling in the Arctic National Wildlife Refuge at the expense of the environment.

Sen. Joseph Lieberman, the Democratic nominee for vice president in 2000, said the administration has been influenced by right-wing interests that would have him drill for oil on pristine lands and allow too much arsenic in water.

"When you get loose about the amount of arsenic in water, which we're worried causes cancer, when you say you're going to drill in one of the most beautiful places the good Lord has given us in America, the arctic refuge, that's not sensible centrism," Lieberman, D-Conn., told CBS.

The latest Newsweek poll found that 41 percent of Americans feel Bush is committed to protecting the environment. Lieberman, a member of the Senate Environment and Public Works Committee, said Bush was "outside the mainstream of where most Americans are" on the issue.

In recent weeks, Bush has endorsed a treaty seeking a worldwide phase-out of a dozen highly toxic chemicals; announced plans for a new standard within nine months on arsenic in drinking water; and upheld Clinton administration regulations requiring thousands more businesses to report releases of toxic lead.

The Green Party's defeated presidential candidate, Ralph Nader, said he believes the administration rolled out its environmental policies in recent weeks in response to polls that show Americans think Bush is unfriendly to the environment.

"They're retreating because they can't be overtly anti-environment in this country and not lose votes. No major party can do that overtly," Nader told Fox News Sunday.

Specifically, environmentalists criticize Bush for rescinding a Clinton order that would have limited arsenic in drinking water to no more than 10 parts per billion; for proposing limits on the ability of environmental groups to get rare plants and animals added to the endangered species list; and retreating from a campaign pledge to regulate carbon dioxide emissions from power plants.

On arsenic, Whitman said the administration would prefer to base its policy on science rather than politics and wants further study to determine what the proper level should be. She said it is too early to say whether the level will be lower or higher than the Clinton administration standard.

Interior Secretary Gale Norton told ABC's This Week that her agency shifted funds away from one program on environmental species to increase the amount of money it uses on "really recovering species."

Lieberman threatened to subpoena the EPA to get information about how the administration has made its environmental decisions. He believes Bush officials only spoke to people on one side of the issue.

"I'm trying, on behalf of the people, to get information which will help me understand, what did the Bush administration do?" Lieberman said.

Also Sunday, Norton played down a report in Time magazine that Bush senior adviser Karl Rove said the administration would not push for drilling in the arctic refuge.

Norton said on CNN's Late Edition that Rove told her earlier Sunday that "he still believes that it is something that we should push forward with."