HOUSTON (Dow Jones)--Responders at the site of the mile-deep BP PLC (BP, BP.LN) spill in the Gulf of Mexico captured some 25,000 barrels of oil Thursday, the U.S. government-appointed leader of the response effort said Friday. U.S. Coast Guard Adm. Thad Allen said in a news conference that he was "very pleased" to report the figure, which was higher than a previous estimate of 16,000 to 17,000 barrels a day given Thursday. The increase follows the arrival of a second vessel at the site, named the Q4000, which is flaring all the oil and gas it is producing. Allen said that responders are on track to increasing the rate at which they capture oil from the leaking Macondo well to 53,000 barrels a day by the end of the month. "We're going to max out at that point," he said, and responders will have to decide whether to replace the current system with more permanent floating production and offloading units that will be able to resist storms and collect up to 60,000 to 80,000 barrels a day. The ultimate effort to kill the leak by drilling two relief wells is also progressing, Allen said. The first relief well is "starting to close in on the wellbore," Allen said, at a depth of 10,677 feet--nearly 700 feet deeper than on Thursday morning. A second back-up well was at a depth of about 4,600 feet. The official estimate for the completion of the first relief well is mid-August. -By Angel Gonzalez, Dow Jones Newswires, 713-547-9214;[email protected] (END) Dow Jones Newswires June 18, 2010 10:15 ET (14:15 GMT)