The legislation, introduced by Sen. Shelley Moore Capito, R-W.Va., would allow states to opt out of complying with the new EPA regulations while preventing the federal government from tying highway funding to a state's implementation of the regulations.
Sens. Thad Cochran and Roger Wicker say in a news release that the EPA regulations could potentially increase energy costs for families and businesses in Mississippi and nationwide.
A federal appeals court ruled Tuesday that the EPA complied with the law in deciding which areas of the country failed to meet federal limits on smog-forming pollution.
States including Mississippi had challenged the EPA's finding that certain areas in their states had violated the standard.