Before lower-grade gas pumps can be used again, companies like Tank Cleaning Industrial will have to clean them out.

Back in 2004, several automakers got together to create a more pure form of gasoline to meet strict standards set by the U.S. Environmental Protection Agency (EPA), now known as Top Tier gasoline.

WASHINGTON (Reuters) - Cleaning up about half of the 117,000 leaking underground fuel storage tanks nationwide will cost the public about $12 billion, Congress' investigative arm said in a report ...