BP officials said at an afternoon media briefing government and company scientists were arriving at the conclusion that methane percolating into the gulf probably was a natural occurrence and not linked to the well destroyed in an April 20 explosion, The New York Times reported.
Meanwhile, BP was given until Tuesday to make sure it has representatives teamed with government officials in all states affected by the gulf oil spill.
National Incident Commander Thad Allen said in a statement the British oil giant was told to have staff paired with state and federal commanders in each affected state to expedite projects and response activities to protect shoreline and recover oil.
Allen, a retired U.S. Coast Guard admiral, said the BP representatives must have authority to commit company resources to response activities.
"Over the past several weeks, control over federal planning and tactical operations in each state has been delegated to the Coast Guard deputy incident commanders, and this authority will be exercised in coordination with their governor-appointed state counterparts," Allen said.
"To achieve even more control over this response at the state level, a BP representative must work with the group to ensure that decisions that are made can be carried out quickly and efficiently."
The possibility of foul weather also reared its head Monday. Accuweather.com said a well-developed tropical wave currently bringing strong winds and rough seas north of Puerto Rico could develop into a tropical depression late in the week and move into the eastern Gulf of Mexico by the weekend.
Gusty winds and thunderstorms could threaten the oil spill area, Accuweather.com said.
BP said it hoped to keep the containment cap closed until a relief well is finished by mid-August when the company hopes to permanently seal the well.
Pressure tests detected seepage "a distance from the well," Allen said Sunday in a letter to the company. Allen told BP Chief Managing Director Bob Dudley the company must report any discoveries of future seepage within 4 hours and to follow more stringent rules as the testing continued.
"(Monitoring) of the seabed is of paramount importance during the test period," Allen said.
The pressure testing, which started Thursday with the closing of valves on the cap to assess the condition of the well, was expected to last two days but government officials said the test could be extended for 24 hours at a time after scientific reviews.
"We're hopeful," Doug Suttles, BP's chief operating officer for exploration and production, said Sunday. "Right now we do not have a target to return the well to flow."
Oil began flowing into the gulf following the April 20 explosion on the Transocean Deepwater Horizon rig leased by BP. The blast killed 11 workers and the rig sank two days later.
BP said on its Web site Monday pressure inside the well recently had been measured at about 6,792 pounds per square inch and continued to rise slowly.
The company said its initial relief well had reached a depth of 17,864 feet as of Sunday and the next scheduled operation is to carry out what it called a ranging run. Ranging runs will be used to guide the drill bit to an intercept point with the damaged well. After interception, operations are expected to begin to kill the flow of oil and gas from the reservoir by pumping specialized heavy fluids down the relief well, BP said.
Drilling of the second relief well, now down to 15,874 feet, has been temporarily halted so as not to interfere with the ranging runs being performed in the first relief well, Bp said.
"Although uncertainty remains, the first half of August remains the current estimate of the most likely date by which the first relief well will be completed and kill operations performed," BP said on its Web site.