BP has said that in the period from May 17 to May 23, the oil rate collected by the riser insertion tube tool (RITT) has ranged from 1,360 barrels of oil per day (bopd) to 3,000bopd, and the daily gas rate has ranged from four million cubic feet per day (mmcfd) to 17mmcfd.

In the same period, the average daily rate of oil and gas collected by the RITT containment system at the end of the leaking riser has been 2,010 barrels of oil per day (bopd) and 10 mmcfd of gas. The oil is being stored and gas is being flared on the drillship Discoverer Enterprise, on the surface 5,000ft above.

According to the company, subsea efforts continue to focus on progressing options to stop the flow of oil from the well through interventions via the blow out preventer (BOP) and to collect the flow of oil from the leak points.

Plans continue to develop a so called ‘top kill’ operation where heavy drilling fluids are injected into the well to stem the flow of oil and gas and ultimately kill the well. Most of the equipment is on site and preparations continue for this operation, with a view to deployment in a few days, BP said.

The US Government has appointed a flow rate technical team (FRTT) to determine the well flow rate. The FRTT includes the US Coast Guard, NOAA, MMS, Department of Energy and the US Geological Survey.

Drilling of the first relief well, which began on May 2 continues as does drilling of a second relief well, begun on May 16. Each of these wells is estimated to take some three months to complete from the commencement of drilling, the company said.