The firm claims the cap placed on the broken well is capturing between 15,000 and 16,000 barrels a day and has a maximum capacity of 18,000 — but scientists have doubled their estimate of the leak size to 40,000 barrels a day.
The company hopes to start operating a second ‘riser’ pipeline in addition to the lower marine riser package (LMRP) containment cap early this week. However, this will only be able to capture a maximum of 10,000 barrels a day.
Plans are underway to place a sealing cap on the well and install two free-standing risers, each capturing up to 25,000 barrels a day. However, the first of these will not be in operation until 1 July.
The two relief wells currently being drilled in order to permanently stop the leak will not be finished until August.
One Gulf drilling expert has warned that, in a worst-case scenario, it may take until Christmas to contain the leak fully.
‘The probable outcome is much better but the technological challenges.. are enormous,’ Nansen Saleri, chief executive of the consultancy group Quantum Reservoir Impact, told The Guardian.
If the new estimate of 40,000 barrels a day is correct, the size of the spill will have reached a total of two million barrels since the leak began on 20 April. BP claims to have captured 127,000 barrels through the LMRP cap, which has been operating for 10 days.
Engineers have increased the daily amount of oil captured by the cap by optimising chokes on the surface but, in a change of plan, have left open the vents in the LMRP that are designed to let oil escape to release pressure.
A second riser will this week begin transporting oil and gas from the choke line of the failed Deepwater Horizon blow-out preventer (BOP) to a Q4000 vessel on the surface.
This oil will be flared instead of captured using an EverGreen burner. This technology is new to the Gulf of Mexico but has been used elsewhere in the world, and relies on air compressors to more efficiently burn the oil.
Trent Wells, BP’s senior vice-president, exploration and production, said the firm would need to bring in another ship to store the oil. ‘The only way to get this done quickly and effectively through the Q4000 was to burn the oil and gas and not just the gas,’ he said.
The company estimates the cost of the clean-up so far at $1.6bn and it faces fines of up to $4,300 for each spilt barrel. Its share price fell by two per cent this morning to 384p.