BP Deepwater Horizon update

Timeline based on BP annoucements since the initial rig accident on 20 April 2010 (share price then (655.40p):

19 September (407.65p)

Statement by BP America on Completion of MC252 Relief Well: Today’s completion of relief well operations on the Macondo well is a significant technological accomplishment and another important milestone in our continued efforts to restore the Gulf Coast. Our work is not finished, however. BP remains committed to remedying the harm that the spill caused to the Gulf of Mexico, the Gulf Coast environment, and to the livelihoods of the people across the region. BP will continue sharing what we have learned in an effort to prevent a tragedy like this from ever being repeated. We also believe that the industry will gain important insights on how to be better prepared to respond to any future incidents.”

19 September (407.65p)

BP confirms that well kill operations on the MC252 well in the Gulf of Mexico are now complete, with both the casing and annulus of the well sealed by cement. The MC252 well had been shut-in since 15 July and cementing operations in August, following the static kill, provided an effective cement plug in the well’s casing. The relief well drilled by the DDIII drilling rig intercepted the annulus of the MC252 well on 15 Sept, followed by pumping of cement into the annulus on 17 Sept. BP, the federal government scientific team and the National Incident Commander have now concluded that these operations have also successfully sealed the annulus of the MC252 well. BP said it would next proceed to complete the abandonment of the MC252 well, which includes removing portions of the casing and setting cement plugs. A similar plugging and abandonment of both relief wells will occur as well. The company is also to start dismantling and recovering containment equipment and decontaminating vessels that were in position at the wellsite.

17 September (407.65p)

Relief well drilling from the Development Driller III (DD3) re-started at 7:15am on Wednesday, and operations completed drilling the final 45 feet of hole. This culminated with the intercept of the MC252 annulus and subsequent confirmation at 4:30pm. CDT Thursday. Total measured depth on the DD3 for the annulus intercept point was 17,977 feet. Operations conducted bottoms up circulation, which returned the contents of the well’s annulus to the rig for evaluation. Testing of the drilling mud recovered from the well indicated that no hydrocarbons or cement were present at the intersect point. Therefore, no annulus kill is necessary, and the annulus cementing will proceed as planned. The MC252 well should be completely sealed on Saturday. Once cementing operations are complete, the DD3 will begin standard plugging and abandonment procedures for the relief well. The Development Driller II continues its work to gather additional data from the MC252 well and try to determine the location of the drill pipe that was originally in the well at the time of the accident. Subsequently plug and abandonment activities will commence in accordance with the approved procedure.

13 September (416.05p)

BP re-started relief well drilling operations from the Development Driller III (DD3) at 1:40 p.m. CDT following the installation of a lock down sleeve, a mechanical device that secures the MC252 well’s casing hangar. The DD3 is drilling toward the MC252 well intercept point, currently about 50 feet below. Relief well operations will consist of drilling and ranging runs that will guide the rig’s drill bit to intercept the well’s annulus. Following the intercept, heavy drilling mud and cement will be pumped into the annular space to complete the isolation of the MC252 well.

10 September (411.65p)

Diagnostic operations over the last few days to better understand the MC252 well’s condition have been successfully completed, BP said. The diagnostics were performed by the Development Driller II, which is currently latched to the well. A lead block impression test was completed in order to determine the condition of the casing hangar, located near the well head. The test, which uses soft lead metal to form an impression of the casing hangar, shows that the hangar was in the proper location and had not lifted. BP will next install a lock down sleeve – a mechanical device that completely secures the casing hangar and the annulus. Once the lock down sleeve is installed and tested, BP will re-start the relief well operations at the weekend in order to intercept the well annulus. The relief well is the last step in completely killing the MC252 well.

8 September (412.15p)

Shoddy work, materials and management practices were the basic causes of the Deepwater Horizon disaster, according to BP’s report into the 20 April explosion and fire on the oil rig, which killed 11 people and caused massive pollution in the Gulf of Mexico. Read more

6 September (406.50p)

BP announced that a number of operations had been completed to allow the DDIII drilling rig to be in a position to begin drilling the relief well to intercept the MC 252 well annulus. The capping stack on top of the Deepwater Horizon (DWH) Blow Out Preventer (BOP) was removed by the drillship Discoverer Enterprise on 2 Sept, with the DWH BOP then removed from the MC252 well by the Q4000 on 3 Sept. The DDII then moved into place with its BOP, which was installed on top of the MC252 well later that day. The DWH BOP was lifted to the surface on 4 Sept and taken into custody by the US Department of Justice as evidence in its ongoing investigation into the incident.

3 September (401.70p)

Following the completion of cementing operations on the well on 5 Aug, pressure testing indicated that there was an effective cement plug in the casing. Operations have started to replace the Deepwater Horizon (DWH) drilling rig’s failed blow-out preventer (BOP) with the DDII drilling rig’s BOP in order to allow operations to complete the relief well to resume. The capping stack on top of the DWH BOP was removed by the drillship Discoverer Enterprise on 2 Sept. Following the removal of the capping stack, the Q4000 support vessel is to connect a riser to the DWH BOP as part of ongoing operations to remove the BOP from the well. The DDII drilling rig will then be expected to move its BOP into place. The DDIII drilling rig is on standby in readiness to resume drilling the relief well. The well is at a measured depth of 17,909 feet and progressing to intersect with the MC252 well will involve drilling, alternating with ranging runs to confirm proximity to the well. Depending upon weather conditions, mid-September is BP’s latest estimate of the most likely date by which the relief well will intercept the MC252 well annulus.

25 August (375.15p)

BP revealed that it is deploying a new technology to enable nearly constant monitoring in the Gulf of Mexico by two satellite-controlled, unmanned vehicles, called Wave Gliders. The vehicles, which were developed by Liquid Robotics in Silicon Valley, California, get their propulsion power from wave action and use solar power for their electronics. They will be deployed beginning today and begin a months-long, ongoing research program in the Gulf of Mexico. The technology allows deployment of sensors persistently, for the long term, to monitor key environmental variables. including: water quality - detection of any emulsified, dissolved and dispersed oil in water; phytoplankton (chlorophyll); colored, dissolved oxygen matter (CDOM), as well as weather and water temperature data.

9 August (432.75p)

Following the completion of cementing operations on the MC252 well on 5 Aug, pressure testing was performed which indicated there is an effective cement plug in the casing. BP said itbelieved the static kill and cementing procedures had been successfu and confirmed that there is currently no oil flowing into the Gulf from the MC252 well, which has been shut-in since 15 July. BP continues to progress the relief well operations that commenced on 2 May. The well is currently at a measured depth of 17,909 feet. Progressing towards the intersect with the MC252 well will involve drilling alternating with ranging runs to confirm proximity to the well. Depending upon weather conditions, BP said 15 Aug was the best current estimate of the most likely date by which the first relief well will intercept the MC252 well annulus. Meanwhile, operations on a second relief well, which started 16 May, have been suspended at a measured depth of 15,874 feet, so as not to interfere with the completion of the first relief well.

5 August (423.40p)

BP finished cementing operations at the MC252 well at 20:15 GMT / 14:15 CDT, as part of the static kill procedure. The operation took five hours to complete. The company is now monitoring the well to confirm the effectiveness of the procedure, which is part of BP’s strategy to kill and isolate the well, and will complement the upcoming relief well operation.Subject to weather conditions, BP said mid-August remains the current estimate of the most likely date by which the first relief well will intercept the Macondo well annulus.

4 August (419.98p)

The MC252 well appears to have reached a static condition, which, said BP, represents “a significant milestone”. The well pressure is now being controlled by the hydrostatic pressure of the drilling mud, which is the desired outcome of the static kill procedure carried out 3 Aug (US Central Time). Pumping of heavy drilling mud into the well from vessels on the surface began at 21.00 GMT / 1500 CDT on 3 August and was stopped after about eight hours of pumping. The well is now being monitored, per the agreed procedure, to ensure it remains static. Further pumping of mud may or may not be required depending on results observed during monitoring. The start of the static kill was based on the results of an injectivity test, which immediately preceded the static kill and lasted about two hour. BP is now assessing whether to inject cement in the well via the same route .The goal is to kill and isolate the well, complementing the upcoming relief well operation – the ultimate way to kill and permanently cement the well.

3 August (415.65p)

Based on the results of the injectivity test, BP started pumping drilling mud at 21:00 GMT / 15:00 CDT as part of the static kill operations. The aim of these procedures is to assist with the strategy to kill and isolate the well, and will complement the upcoming relief well operation, the company said. The first relief well, which started 2 May, has set its final 9 7/8-inch casing, though operations on the relief wells are suspended during static kill operations. Depending upon weather conditions, BP estimates mid-August as the most likely date by which the first relief well will intercept the Macondo well annulus, and kill and cement operations commence.

2 August (413.10)

A bit like the oil leak, BP’s announcements have started to dry up in recent days. One release has finally trickled through, though, to say that final preparations to commence with the injectivity test, a small hydraulic leak was discovered in the capping stack hydraulic control system. The injectivity test, previously expected to take place today, has been rescheduled until the leak is repaired. BP now anticipates that the injectivity test and possibly the static kill will take place 3 Aug.

26 July (416.95p)

Following the passing of the weather system, associated with Tropical Storm Bonnie, the DDIII drilling rig returned to the relief well site on 24 July 24 to reconnect with the well and resume drilling operations. These steps, said BP were likely to take several days. Second drilling rig DDII is also moving back into position to reconnect to the second relief well. However, work on the second relief well has been suspended so as not to interfere with the first. The MC252 well has been successfully shut-in for integrity testing since 15 July.
BP continues to closely monitor the MC252 well and well-capping structure, under the guidance of the Unified Command.

23 July (394.90p)

BP finally gets back on line (around 9am GMT) to announce relief well activities at the MC252 well site will be temporarily suspended because of potentially adverse weather associated with Tropical Storm Bonnie, which is projected to track into the Gulf of Mexico. The MC252 well remains shut-in. The well has been shut-in for integrity testing the past seven days.
BP will continue to monitor the MC252 well as long as weather permits.

22 July (399.05p)

Still no new update from BP, but industry rivals Chevron, ConocoPhillips, ExxonMobil and Shell have launched a plan to build and deploy a rapid response system that will be available to capture and contain oil in the event of a potential future underwater well blowout in the deepwater Gulf of Mexico. Read more

21 July (398.90p)

No new BP announcement as of noon GMT. However, on 20 June the US National Incident Commander Admiral Thad Allen confirmed the federal government’s authorisation for BP to continue the well integrity test for another 24 hours. He also reported on efforts to look for anomalies in pressure readings and collect acoustic, sonar and seismic data, as well as the potential for severe weather in the Gulf.

19 July (398.04p)

At this time (around 8.30am GMT), the well integrity test on the MC252 exploratory well continues, with the three-ram capping stack still closed and shutting in the well. The other sub-sea containment systems – the Q4000 and Helix Producer ship systems – temporarily suspended. Pressure inside the well is around 6,792psi, and rising slowly. Data from the well site in being analysed to determine whether to extend the well integrity test or return to containment options. The Q4000 had been capturing around 8,000 barrels a day (b/d) of oil, the Helix Producer ship has the capacity to capture approximately 20,000 - 25,000 b/d of oil, while other planned measures could increase recovery rates to 60,000-80,000 b/d. To date, the total volume of oil collected or flared by the containment systems is around 826,800 barrels. The first relief well had reached a depth of 17,864 feet as of 18 July, the second relief well 15,874 feet: BP estimating mid- August as the most likely date for completion of the first relief well and kill operations to be performed.

16 July (413.25p)

Well integrity test is still ongoing. Currently the well remains shut-in with no oil flowing into the Gulf. Pressure continues to rise and is currently above 6700 psi. Due to the well integrity test, no oil was recovered during the last 12 hours on 15 July (noon to midnight).

15 July (401.75p)

Following installation of the capping stack, the well integrity test on the MC252 well commenced. During the test, the three-ram capping stack is closed, effectively shutting in the well, while Q4000 and Helix Producer sub-sea containment systems have been temporarily stopped. BP expects that no oil will be released to the ocean during the test, but says that this will not be an indication that oil and gas flow from the wellbore has been permanently stopped. The total oil recovered on 15 June was approx. 9,305 barrels, with approx. 22.5 million cubic feet of natural gas were flared. Total oil recovered from the lower marine riser package LMRP Cap, Q4000, and Helix Producer ship systems since they were implemented is approx. 804,800 barrels. An additional 22,000 barrels were collected from the RIT tool earlier in May bringing the total recovered to approx. 826,800 barrels.

12 July (398.02p)

Three-ram capping stack installed on the Deepwater Horizon lower marine riser package (LMRP) at 7pm. CDT; completing the installation of the new sealing cap. Sealing cap assembly has replace the existing LMRP containment cap over the Deepwater Horizon’s failed blow-out preventer. The Helix Producer ship’s containment system has started operations, while the Q4000 containment system continues to capture oil and gas from the MC252 well and flare the hydrocarbons safely at the surface. Unlike the LMRP containment cap system, the Q4000 and Helix Producer systems are connected to the kill and choke lines on the BOP via the existing top kill manifold. Relief well operations continue throughout this period and remain the sole means to permanently seal and isolate the well.

10 July (364.80p)

Lower marine riser package (LMRP) cap removed at approx 12:40pm CDT on 10 July. Process included the removal of six bolts along with the LMRP flange. A transition spool was subsequently installed on the existing flange. The next step is to install a capping stack that has three closing rams. On 10 July, the LMRP containment system collected 7,096 barrels of oil, and the Q4000 flared an additional 8,100 barrels of oil. The total volume of oil collected or flared by the containment systems is approximately 749,100 barrels. Work on the first relief well, which started 2 May, has reached a measured depth of 17,810 feet on July 11 and a tenth ’ranging’ run was completed. Following the running and cementing of the 9 7/8-inch casing and further ranging runs, the relief well is intended to intercept the original well at about 18,000 feet. Operations will then – estimated mid-August – begin to kill the flow of oil and gas from the reservoir by pumping specialised heavy fluids down the relief well. The second relief well, which started 16 May, is just below 16,000 feet and preparing to cement casing.

9 July (364.80p)

BP set to replace the existing lower marine riser package (LMRP) containment cap over the Deepwater Horizon’s failed blow-out preventer (BOP) with a new sealing cap assembly.  The new sealing cap contains three closing rams and multiple ports for connection to additional containment options. The new cap creates the potential to increase oil and gas containment capacity to greater than 50,000 barrels per day and should improve containment efficiency during hurricane season by allowing shorter disconnect and reconnect times. The new cap assembly also might simplify future well kill and cementing procedures through the relief wells, which in turn could increase the probability of success for those operations. In addition, the new cap should enable a shut-in test to be performed to determine integrity of the MC252 well.

5 July (328.96p)

Around 25,198 barrels of oil were collected or flared by the two containment systems and 57.0 million cubic feet of gas were flared. The lower marine riser package (LMRP) system connected to the Discoverer Enterprise collected 17,022 barrels of oil, and the Q4000 flared an additional 8,176 barrels of oil. To date, the total volume of oil collected or flared by the containment systems is approximately 585,400 barrels. Work on the first relief well, started on 2 May has reached a depth of 17,725 feet on 4 July and a sixth ‘ranging’ run was completed. The second relief well, which started 16 May, has now reached a measured depth of 13,871 feet. Both wells are still estimated to take around three months to complete from commencement of drilling.

28 June (308.25p)

The first relief well, which started drilling 2 May, has reached a measured depth of 16,546 feet and has completed  a second ”ranging” run using specialist equipment inserted into the well to help more precisely locate the MC252 well. Drilling and ranging operations will continue over the next few weeks as the well progresses towards the target intercept depth of approximately 18,000 feet. Once intercept has occurred, operations are expected to begin to kill the flow of oil and gas from the reservoir by pumping specialised heavy fluids down the relief well.The second relief well, which started May 16, is at a measured depth of 12,038 feet. Both wells are still estimated to take three months to complete from commencement of drilling.

26 June (305.73p)

The LMRP containment system connected to the Discoverer Enterprise has collected 14,730 barrels of oil, and the Q4000 flared an additional 8,020 barrels of oil. To date, the total volume of oil recovered or flared by containment systems is around 435,600 barrels.

25 June (305.73p)

To date, the total volume of oil recovered or flared by the two containment systems is approximately 364,500 barrels. The first relief well reached a depth of 16,275 feet on 23 June before the drillstring was removed from the well to carry out the first ’ranging’ run using wireline. During the ranging run, the MC252 well was successfully detected. Subsequent ranging runs will be needed to more precisely locate the well. Drilling and ranging operations will continue over the next few weeks towards the target intercept depth of approximately 18,000 feet, when ’kill’ operations are expected to begin. The second relief well, which started 16 May, is drilling ahead at a measured depth of 10,500 feet.

23 June (333.50p)

This morning at 0845 CDT a discharge of liquids was observed from a diverter valve on the Discoverer Enterprise. As a precaution, the attached lower marine riser package (LMRP) containment cap system has been moved off the Deepwater Horizon’s failed blow-out preventer (BOP) until the liquids are analysed. Capture of oil and gas through the BOP’s choke line via a manifold to the Q4000 vessel on the surface continues. The LMRP was reinstalled on the BOP at approximately 1830 CDT, and resumed collecting oil and gas at 1900 CDT.  On June 23, the LMRP containment system connected to the Discoverer Enterprise collected 8,300 barrels of oil, and the Q4000 flared an additional 8,530 barrels of oil.

21 June (349.50p)

Two systems continue to collect oil and gas flowing from the MC252 well and transport them to vessels on the surface. The lower marine riser package (LMRP) containment cap located on top of the Deepwater Horizon’s failed blow-out preventer (BOP). This system, which was installed on June 3, takes oil and gas to the Discoverer Enterprise. A second system, which started on 16 June, is connected directly to the BOP and carries oil and gas through a manifold and hoses to the Q4000 vessel on the surface.

19 June (359.70p)

On 19 June, around 11,050 barrels of oil collected and 25.6 million cubic feet of natural gas was flared on the Discoverer Enterprise. This is less than recent averages because process facilities were shutdown for part of the day. In the same 24-hour period, 9,990 barrels of oil and 17.8 million cubic feet of natural gas were flared on the Q4000. The total volume of oil recovered from both the LMRP containment cap system and the Q4000 since they became operational is approximately 249,500 barrels. Work on the first relief well, which started 2 May, has reached a measured depth of 15,936 feet. The second relief well, which started 16 May, is at a measured depth of 10,000 feet.

16 June (337.00p)

BP announced that oil and gas is flowing through a second containment system attached to the Deepwater Horizon rig’s failed blow out preventer (BOP). This second system supplements the lower marine riser package (LMRP) cap containment system, which remains in operation. The new system is connected directly to the BOP and carries oil and gas through a manifold and hoses to the Q4000 vessel on the surface. The Q4000 uses a specialised clean-burning system to flare oil and gas captured by this second system.

15 June (342.00p)

At 2:15 p.m. CDT, the Discoverer Enterprise resumed containment operations following a short outage caused by a lightning strike at 9:30 this morning. The U.S. Coast Guard gave authorization for the operation to resume at 1:40 p.m. after the ship’s crew completed safety and operational assurance inspections.

14 June (362.00p)

In the first 12 hours of June 13 (midnight to noon), the lower marine riser package (LMRP) containment cap collected about 7,720 barrels of oil, with 16.9 million cubic feet of natural gas flared. On 12 June, approximately 15,000 barrels of oil were collected and 32.9 million cubic feet of natural gas were flared. The total volume of oil collected by the LMRP cap system since it began operation is put at 127,000 barrels, with a further 22,000 barrels of oil previously had been collected through use of the Riser Insertion Tube Tool. The first relief well has currently reached a depth of 13,978 feet. The second relief well is at 9,022 feet.

10 June (365.50p)

In the first 12 hours of June 9 (midnight to noon), the lower marine riser package (LMRP) containment cap, installed on 3 June, collected around 7,920 barrels of oil, with 15.7 million cubic feet of natural gas flared. On 8 June, around 15,000 barrels of oil were collected and 29.4 million cubic feet of natural gas were flared. Preparations for additional planned enhancements to the LMRP containment system continue to progress. Work on the first relief well, which started 2 May, has reached a depth of 13,978 feet, with the second relief well, which started 16 May, at 8,576 feet.

7 June (430.30p)

The lower marine riser package (LMRP) containment cap, installed on 3 June, continues to collect oil and gas flowing from the well and transport them to the Discoverer Enterprise drillship. On 5 June, 10,500 barrels of oil was collected and 22 million standard cubic feet of natural gas was flared. From 3-5 June, the volume of oil collected was 16,600 barrels and 32.7 million standard cubic feet of natural gas was flared.  Work on the first relief well, which started 2 May, has currently reached a depth of 12,956 feet. The second relief well, which started May 16, is at 8,576 feet, and testing of the BOP is continuing.

4 June (433.35p)

Oil and gas is being received onboard the Discoverer Enterprise following the successful placement of a containment cap on top of the Deepwater Horizon’s failed blow-out preventer (BOP). This follows the cutting and removal of the riser pipe from the top of the BOP’s lower marine riser package (LMRP). It is expected to take one or more days for flow rates of oil and gas to stabilize and it is not possible at this stage to estimate how much oil and gas will be captured by this containment system.

1 June (430.00p)

Preparations are ongoing for deployment of the lower marine riser package (LMRP) cap containment system. Remotely operated vehicles (ROVs) are engaged in preliminary operations, including preparing for operations to cut through and separate the damaged riser from the LMRP at the top of the Deepwater Horizon’s failed blow-out preventer (BOP). Work on the first relief well, which started on May 2, continues and it has currently reached a depth of 12,090 feet. Drilling operations on a second relief well resumed on May 30 at 8,567 feet.

31 May (494.80p)

BP said it plans to further enhance the lower marine riser package (LMRP) containment system currently scheduled to be deployed that week. A first planned addition is to use the hoses and manifold that were deployed for the ‘top kill’ operation to take oil and gas from the failed Deepwater Horizon blow-out preventer through a separate riser to an intervention vessel on the surface, in addition to the LMRP cap system.  Another plan is to direct oil and gas to a new free-standing riser ending approximately 300 feet below sea level. A flexible hose then will be attached to a containment vessel to permit the system to more effectively disconnect and reconnect the riser to provide the greatest flexibility for operations during a hurricane.

29 May (494.80p)

BP started the “top kill” operations to stop the flow of oil from the MC252 well in the Gulf of Mexico at 1300 CDT on May 26, 2010. However,despite successfully pumping a total of over 30,000 barrels of heavy mud, in three attempts at rates of up to 80 barrels a minute, and deploying a wide range of different bridging materials, the operation did not overcome the flow from the well.  Drilling of the first relief well is currently at 12,090 feet, while drilling of the second relief well is set to recommence from 8,576 feet.

28 May ((494.80p)

Operations on the top kill procedure continue. Heavy drilling fluids were pumped under pressure into the BOP starting 26 May at 1300CDT, with the operation continuing through 2400CDT on 27 May – and could extend for another 24 to 48 hours. Preparations continue for deployment of the lower marine riser package (LMRP) cap containment system, now parked alongside the BOP.

27 May (520.80p)

“Top kill” operations continued over the night and are ongoing. There are no significant events to report at this time. BP will provide updates on progress as appropriate.

26 May (492.00p)

A series of diagnostic tests are currently underway on the Deepwater Horizon’s failed BOP to improve understanding of the status and configuration of the BOP and determine whether a ‘top kill’ procedure can be successfully executed. These tests involve pumping drilling fluids into the BOP to measure pressures and validate flow paths. When complete, a decision will be made on the execution of the top kill procedure itself.

25 May (485.20p)

Preparations for top kill operation continue  as is the development of a lower marine riser package (or LMRP) cap containment – an engineered containment device with a sealing grommet. This option would involve removing the damaged riser from the top of the BOP, leaving a cleanly-cut pipe at the top of the BOP’s LMRP. The LMRP cap would be connected to a riser from the Discoverer Enterprise drillship and then placed over the LMRP to capture most of the oil and gas flowing from the well and transporting it to the drillship on the surface. Meanwhile, a BP internal investigation team links accident to failure of multiple control procedures and equipment (See panel)

24 May (493.00p)

Plans continue to develop “top kill” operation including sophisticated diagnostic work. Work goes on to optimise the oil and gas collected from the damaged riser through the riser insertion tube tool (RITT). From 17-23 May, the daily oil rate collected by the RITT has ranged from 1,360 barrels of oil per day (b/d) to 3,000 b/d, and the daily gas rate has ranged from 4 million cubic feet per day (MMCFD) to 17 MMCFD. The average daily rate of oil and gas collected by the RITT containment system is put at 2,010 barrels of oil per day (BOPD) and 10 MMCFD of gas.

20 May (528.80p)

Volume of oil and gas being collected by the riser insertion tube tool (RITT) containment system at the end of the leaking riser is estimated to be about 3,000 barrels a day (b/d) of oil and some 14 million standard cubic feet a day of gas. The oil is being stored and gas is being flared on the drillship Discoverer Enterprise. BP also continues to develop options, including “top kill” operation, to shut off the flow of oil from the well through interventions via the failed BOP.

18 May (534.00p)

Riser insertion tube tool (RITT) containment system at the end of the leaking riser is operational and estimated to be collecting and carrying about 2,000 barrels a day (b/d) of oil to flow up to the drillship Discoverer Enterprise. Produced oil is being stored on the drillship while produced gas is being flared. Plans continue for “top kill” operation, with most of the equipment on site.

17 May (529.90p)

Riser insertion tube tool (RITT) containment system placed in the end of the leaking riser on May 16. Operations began during the day to allow oil and gas to flow through the tool up to the drillship Discoverer Enterprise. Plans continue to be developed for a so called “top kill” operation where heavy drilling fluids are injected into the well to stem the flow of oil and gas, followed by cement to seal the well. The DDII drilling rig has started drilling the second relief well on May 16.

13 May (547.60p)

Top kill” of the well to involve first injecting sealing materials of varying densities and sizes into the internal spaces of the failed BOP, before pumping specialised heavy fluids into the well to prevent further flow up the well. Meanwhile, a small dome has been taken out to the well site and placed on the seabed in preparation for deployment.  A rig to drill the second relief well is currently en route to the site.

10 May (549.20p)

Containment-dome plan abandoned as build up of hydrates had prevented its placement over the main leak point. A second, smaller containment dome is being readied, and will be connected by drill pipe and riser lines to a drill ship on the surface to collect and treat oil. It is designed to mitigate the formation of large hydrate volumes. BP also starts a “top kill” plan to seal the failed blow out preventer.

7 May (561.29p)

Preparation work to lower100-tonne containment dome to the sea bed and connect it to a vessel on the surface.

6 May (572.00p)

Valve that had been attached to the end of a broken drill pipe, one of the three points from which oil was leaking, was closed. This has stopped the flow from this point, but is not expected to affect the overall rate of flow from the well. BP continues to use remotely operated vehicles to monitor the flow of oil from the other two leak points. A 40x24x14 feet steel containment dome, weighing around 100 tonnes, is ready to be lowered to the seabed.

5 May (565.00p)

BP has stopped the flow of oil from one of the three existing leak points on the damaged MC252 oil well and riser in the Gulf of Mexico. At the MC252 well, using remotely operated vehicles (ROVs), a valve has been installed on the end of a broken drill pipe, one of the three points from which oil was leaking. Operation is not expected to affect the overall rate of flow from the well, but will reduce the complexity of the situation being dealt with on the seabed.

4 May (552.84p)

BP has started to drill a relief well to intercept and isolate the oil well at 15:00CDT on 2 May. The new well, in 5,000 feet of water, is planned to intercept the existing well around 13,000 feet below the seabed and permanently seal it. Drill site is about half a mile from the leaking well in Mississippi Canyon block 252, and drilling is to take around three months. Meanwhile US National Oceanic and Atmospheric Administration suggest some 5,000 barrels of oil per day are escaping from the well.

3 May (575.50p)

BP says actions it has taken on the blow out preventer have not resulted in any observed reduction in the rate of flow of oil from the MC252 well.

30 April (575.50p)

BP call other companies including Exxon, Shell, Chevron and Anadarko to help it activate the blow out preventer, and to offer technical support. Estimates that efforts to contain the spill and secure the well are costing about $6 million per day, and rising.

28 April (625.00p)

BP conducts a controlled burn on parts of an offshore oil spill in the Gulf of Mexico.

27 April (610.00p)

US government has launched investigations into the explosion and sinking of the Transocean Deepwater Horizon.

26 April (641.80p)

BP launched comprehensive oil spill response plan.

25 April (639.70p)

BP using remotely operated vehicles to monitor the Macondo/MC252 exploration well, and is planning to activate the blow-out preventer.

24 April (639.70p)

Confirmation that 11 workers died on the Deepwater Horizon oil rig.

22 April (636.40p)

BP activates oil spill response in the US Gulf of Mexico as Transocean Deepwater Horizon drilling rig sinks 130 miles south-east of New Orleans. Includes assessment of the well and subsea blow out preventer with remotely operated vehicles and a plan to drill of a relief well

21 April (648.20p)

Fire caused Transocean’s semi-submersible drilling rig Deepwater Horizon to be evacuated overnight. BP, which operates the licence on which Transocean’s rig was drilling an exploration well, said it was working closely with Transocean and the US Coast Guard, and had been offering help - including logistical support. Most of the 126 member crew is safe but some crew members remain unaccounted for at this time.

20 April (655.40p)

Drilling contractor Transocean Ltd reports fire onboard its semisubmersible drilling rig Deepwater Horizon, at approximately 10:00pm central time in the US Gulf of Mexico. The rig was located about 41 miles offshore Louisiana on Mississippi Canyon block 252.”