A White House memo has created a firestorm after it criticized the Environmental Protection Agency’s classification of greenhouse gas as a public health threat and warned that regulation of CO2 will result in “serious economic consequences” for businesses and the economy.

The document from the Office of Management and Budget questions the EPA’s April assessment because it claims it was not based on a thorough examination of costs and benefits and falls short on solid scientific findings.

Sen. John Barrasso, R-Wyo., exposed the “smoking gun” after he received a nine-page memo marked “Deliberative: Attorney-Client Privilege.”

He presented the document to Lisa P. Jackson, EPA administrator, at a Tuesday hearing of the Environment and Public Works Committee.

“Council in this administration repeatedly, repeated questions the lack of scientific support that you have for this proposed finding,” he told Jackson. “Your findings were political, not scientific.”

He read from the memo. “There is a concern that the EPA is making a finding based on harm from substances that have no demonstrated direct health effects, such as respiratory or toxic effects,” it stated.

On multiple occasions, the document questions the EPA’s judgment in determining that greenhouse gases endanger public health.

“Since tropospheric ozone is already regulated under the Clean Air Act, EPA should explain why those regulations are inadequate to protect public health from the ozone impacts of climate change,” it said.

The OMB memo states:

Making the decision to regulate CO2 under the CAA [Clean Air Act] for the first time is likely to have serious economic consequences for regulated entities throughout the U.S. economy, including small businesses and small communities. Should EPA later extend this finding to stationary sources, small businesses and institutions would be subject to costly regulatory programs such as New Source Review.

Barrasso warned in a blog posting, “This misuse of the Clean Air Act will be a trigger for overwhelming regulation and lawsuits based on gases emitted from cars, schools, hospitals and small business. This will affect any number of other sources, including lawn mowers, snowmobiles and farms. This will be a disaster for the small businesses that drive America.”

The document is a combination of findings from government agencies sent to the EPA notes there are several gray areas in which greenhouse gases are “not well determined” and “not well understood.”

“Despite the findings in the memo, the White House has given the EPA the green light to move ahead with regulation under the Clean Air Act,” Barrasso wrote.

Senior Fellow Marlo Lewis of Competitive Enterprise Institute, a non-profit, non-partisan public policy group, said the memo simply confirms what free-market groups have been saying for months.

“The endangerment finding will trigger a regulatory cascade with potentially severe impacts on energy prices, economic development, and jobs,” he said in a statement.

Lewis said Obama is “playing with political dynamite.”

“Once EPA finalizes the endangerment finding, the stage is set for a flood of litigation to impose draconian Clean Air Act controls on the economy,” he said. “Similarly, litigation groups will demand that the Administration use the Endangered Species Act to stop greenhouse gas emissions.”

Lewis continued, “It will all happen on President Obama’s watch, and he will take all the blame. Republicans will be quick to exploit the political backlash. For the sake of the country and his own political legacy, President Obama should introduce legislation to preclude regulation of greenhouse gases under existing environmental statutes.”

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