The federal government's oil spill chief said Tuesday that seepage two miles from BP's oil cap is coming from another well, tamping down fears that leaks from the ruptured well mean it's unstable.
Retired Coast Guard Adm. Thad Allen also said five leaks in and around BP's well are more like "drips," and aren't yet cause for concern.
The leaks and seepage had raised concerns that the mechanical cap choking off the flow of oil was displacing pressure and causing leaks deep underground. That could cause instability in the seafloor and make the environmental disaster even worse and harder to fix.
Adm. Allen said the well appears stable, and he extended testing of the experimental cap by another day, which means the oil will remain shut in.
The cap is buying time until a permanent plug is in place. Crews are drilling into the side of the ruptured well from deep underground and, by next week, they could start blasting in mud and cement to block off the well permanently. Killing the well deep underground works more reliably than bottling it up with a cap.
Adm. Allen also said he is considering whether to pump heavy mud and cement through the well cap, which would smash the oil in from two directions. The idea is similar to the failed top kill plan that couldn't overcome the pressure of the geyser pushing up.
BP said that plan could work now because there is less oil to subdue.
The seepage was detected over the weekend, and was the first sign of trouble since the cap was closed Thursday.
But Adm. Allen said Tuesday another well is to blame.
"It's actually closer to that facility than it is to the Macondo well," the one that blew out, Adm. Allen said. "The combination of that and the fact that it's not uncommon to have seepage around these" abandoned wells are what convinced engineers that BP's well wasn't the source of the seepage, he said.
There are two wells within two miles of BP's blowout, one that has been abandoned and a second that is not in production. About 27,000 abandoned wells in the Gulf aren't checked for leaks, an Associated Press investigation showed this month.
Mr. Allen said he would accompany Vice President Joseph R. Biden Jr. on a trip to the Gulf on Thursday. The White House said Mr. Biden will visit Theodore, Ala., to assess the government's and BP's efforts to respond to the disaster and to meet with affected residents.
Mr. Biden made his first trip to the region in late June.
• AP writers David Dishneau, Michael Kunzelman and Phuong Le contributed to this report.