Democratic senators at a hearing Wednesday listed a host of Bush-era environmental offenses that they want the nominee for Environmental Protection Agency administrator to address if she's confirmed, which looks likely.

The litany included failures to clean up toxic waste messes, lax regulation of poisonous substances and a recent coal ash spill in Tennessee, as well as questions about the EPA's role in regulating greenhouse gas emissions -- all issues that will fall under Lisa Jackson's jurisdiction if she's confirmed as the agency's next administrator.

Senators seemed pleased with Jackson's credentials as a former EPA employee for 16 years and commissioner of New Jersey's Department of Environmental Protection since 2006. However, Democrats on the Senate Environment and Public Works Committee said they weren't happy with the path EPA has trod under the Bush administration and asked Jackson for serious commitments to change its course.

"EPA works for the American people, and in my view we have seen it hurt the American people these past eight years," said EPW Committee Chairwoman Barbara Boxer, D-Calif. "At this hearing … what I am looking for is a renewed commitment to EPA's mission."

Others want more than that, including Sen. Sheldon Whitehouse, D-R.I., who suggested Jackson conduct a formal probe into the agency's actions over the past eight years.

"Although that was yesterday, yesterday bears on today through EPA's advisory panels that may still contain industry representatives that have been packed on to the panel to influence decisions, (as well as) in tainted regulatory decisions on ozone, soot, mercury," among other things, Whitehouse said. "I think there should be some effort to review what happened."

Jackson said she would be willing to do so, saying an independent audit of the agency would help her do her job by making "sure the programs are functioning as they should, the money is spent as it should be (and) that (the agency) is protecting public health."

Senators heralded Jackson's assertion that EPA decisions under her leadership would hinge on scientific evidence, something many environmentalists and Democratic lawmakers have charged the EPA failed to do under the Bush administration.

"I will administer with science as my guide," Jackson said.

Republican senators, however, seemed wary of Jackson's stance on greenhouse gas regulations, particularly the possibility that she may use current environmental laws, such as the Clean Air Act, to regulate carbon dioxide emissions. Doing so would create economic problems for many businesses and ranchers, who might be penalized for the methane emissions of their animals under such a program, Sen. John Barrasso, R-Wyo., said at the hearing.

"Ranchers in Wyoming know that addressing climate change through the Clean Air Act is a disaster waiting to happen," he said.

Jackson's response indicated she disagreed.

"I think the beauty of many environmental laws is that they were written to address not only the issues of today, but the issues of tomorrow," Jackson said.

This particular issue has been a hot topic for some time, and the Supreme Court ruled last April in a controversial 5-4 decision that carbon emissions constitute pollutants under the Clean Air Act, giving Jackson the legal authority, if she becomes administrator, to regulate carbon dioxide.

This concerns some experts, because they say it could increase energy prices and harm the economy. One of these is Ben Lieberman, a senior policy analyst for energy and the environment at The Heritage Foundation, a conservative think tank.

"This would be a de-stimulus for the economy that would overwhelm any stimulus package for years to come," Lieberman told United Press International.

In addition to addressing carbon dioxide emissions, Jackson assured senators she'll work to prevent toxic spills and pollution problems. In particular, she said she would investigate coal ash storing facilities around the country for potential public health risks -- a concern that recently took center stage in the national media after a billion gallons of the waste, left over from coal-fire power generation, burst out of a holding facility at a Tennessee power plant in late December.

"One of the very important things the EPA must do right away … is to assess the hundreds of other sites out there," like the one in Tennessee, she said.

The EPA decided in 2000 not to regulate the waste, but Jackson said the agency will re-evaluate that position under her leadership.

This commitment, as well as Jackson's position on other pollutants, signaled a welcome change for many environmentalists, including Alex Formuzis, representative of the Environmental Working Group, a non-profit organization.

"Her comments related to reducing the levels of toxic exposure were very encouraging," Formuzis told UPI. "It's clear President-elect Obama's nominee will put the health of our children and families first, instead of last, as it has been under the Bush administration."