The Associated Press reports more than 27,000 abandoned oil and gas wells lurk in the hard rock beneath the Gulf of Mexico.
An AP investigation finds that no one is checking to see if they are leaking. The oldest of these wells were abandoned in the late 1940s.
The review comes as oil continues spewing following the April rig disaster in the Gulf.
The AP investigation uncovered particular concern with 3,500 of the neglected wells -- those characterized in federal government records as "temporarily abandoned."
Regulations for temporarily abandoned wells require oil companies to present plans to reuse or permanently plug such wells within a year.
Oil company representatives insist that the seal on a correctly plugged offshore well will last forever.
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