Energy/Environment Mystery in Gulf of Mexico: Why is oil leaking from Deepwater disaster site?

Oil identified as coming from the Macondo well, site of the 2010 Deepwater Horizon disaster, is leaking into the Gulf of Mexico at the rate of 100 gallons per day. The Coast Guard is investigating.

U.S. Coast Guard/Reuters/Files

Oil is leaking into the Gulf of Mexico at the rate of about 100 gallons per day near the Macondo wellhead, the site of the oil spill over two years ago that became the worst environmental disaster in US history.