FILE – Professional NASCAR drivers use cars already are exempt from the Clean Air Act but North Carolina Republicans want a new law to ensure federal environmental regulations don’t hurt amateur drivers. This photo was taken at a slow shutter speed as crew members perform a pit stop on driver Jimmie Johnson's car during the NASCAR Sprint Cup series Coca-Cola 600 auto race at Charlotte Motor Speedway in Concord, N.C., Sunday, May 25, 2014.
FILE – Professional NASCAR drivers use cars already are exempt from the Clean Air Act but North Carolina Republicans want a new law to ensure federal environmental regulations don’t hurt amateur drivers. This photo was taken at a slow shutter speed as crew members perform a pit stop on driver Jimmie Johnson's car during the NASCAR Sprint Cup series Coca-Cola 600 auto race at Charlotte Motor Speedway in Concord, N.C., Sunday, May 25, 2014. Terry Renna AP
FILE – Professional NASCAR drivers use cars already are exempt from the Clean Air Act but North Carolina Republicans want a new law to ensure federal environmental regulations don’t hurt amateur drivers. This photo was taken at a slow shutter speed as crew members perform a pit stop on driver Jimmie Johnson's car during the NASCAR Sprint Cup series Coca-Cola 600 auto race at Charlotte Motor Speedway in Concord, N.C., Sunday, May 25, 2014. Terry Renna AP