Timor Sea Drilling Spill: Two Months and Still Going

The ongoing Montara / West Atlas oil spill in the Timor Sea off Western Australia is now in its 62nd day. So far, three attempts to intercept and plug the leaking well have failed. Another attempt should happen today. A MODIS / Terra satellite image taken on October 21 – exactly two months after the blowout and spill began – shows slicks and sheen covering 2,600 square miles and approaching within 35 miles of the Kimberley coast. Satellite images show that oil has been moving to the south-southeast from the Montara platform, toward Australia, for the past few days:

NASA/MODIS satellite image, October 21, 2009, with SkyTruth analysis. See all of SkyTruth’s images here.

The Australian Senate held a hearing this week on this relentless spill and the oil company, PTTEP, could offer no justification for their oft-repeated estimate that 400 barrels of oil per day were spewing from the damaged well. This estimate may be an order of magnitude too low. As reported today in The Australian:


A Department of Resources, Energy and Tourism official told Greens senator Rachel Siewert on Wednesday: “The maximum leakage rate from that well could be as much as 2000 barrels of oil a day, with condensate as well.”

Senator Siewert acknowledged that did not mean 2000 barrels were actually coming out, rather that it was the maximum amount possible if the well were operating at full capacity.


At the 2,000 barrel per day rate, over 5 million gallons would have been spilled so far. That’s getting into Exxon Valdez territory.

Could this happen in the US? We can’t say until we get more details about what caused this blowout. But it’s worth noting than in the US Gulf of Mexico, blowouts are not rare occurrences: the US Minerals Management Service has investigated 18 blowouts and 13 “loss of well control” incidents since 1983, several involving fires and fatalities. In 1992, the Greenhill Petroleum blowout and fire sent 70,000-120,000 gallons of oil into Timbalier Bay, Louisiana. Blowouts happened twice in 2007, and the most recent loss of well control was in 2008. And many more, less-serious, incidents can be found here.

Timor Sea Drilling Spill – 3rd Relief Attempt Fails

Ugh, back to the ongoing Montara / West Atlas oil spill. Looks like the third time’s not the charm in the Timor Sea, where the latest attempt to get this massive spill under control has failed. Oil and natural gas have been spewing into the ocean and air off Western Australia for 58 days. The Montara oil platform — and the West Atlas drill rig that was working there when the blowout occurred on August 21 — are still at high risk for fire and explosion, and cannot be approached.

This is now being reported as the worst oil spill in Australia since offshore drilling began there 40 years ago.

So far we’ve seen no reports detailing what actually went wrong during drilling that caused a previously-completed well on the Montara platform to blow out. The Norwegian company that operates the West Atlas rig, Seadrill, is also currently working in the U.S. Gulf of Mexico on complex, ultra-deepwater drilling projects. Seadrill is a major global offshore drilling contractor, with a fleet of 42 drill rigs. They’ve got an office in Houston, Texas, and have identified the Gulf of Mexico as a targeted area of operation for the company.

At this point we’ve seen no evidence that a Montara-type drilling accident couldn’t happen anywhere, including in US waters. The public deserves a comprehensive and independent analysis of the Montara failure, once the well has been plugged and the platform can be re-occupied.

Timor Sea Drilling Spill – 2nd Relief Attempt Fails

It’s now Day 54 of the ongoing Montara oil spill off Western Australia, and the second attempt to intercept the damaged well and shut it down has failed. The next try should happen over the weekend. Third time’s the charm – we hope.

At this point, using PTTEP’s estimate of 400 barrels of oil spilled per day, at least 900 thousand gallons have been spilled into the Timor Sea since the blowout occurred on August 21. Using our estimate of 3,000 barrels per day, based on the known flow rates of nearby wells, nearly 7 million gallons have been spilled so far.

Timor Sea Drilling Spill – 1st Relief Attempt Fails

Perth Now reports that the first attempt to shut down the uncontrolled spill of oil and gas from a damaged well on the Montara platform has failed. It’s a highly challenging operation: drillers on a nearby rig that was brought in from Singapore, the West Triton, are attempting to intercept the damaged Montara well at a point more than 8,500′ below the seafloor and pump enough heavy mud into it to stop the flow. It will take up to 4 days to make another pass at the well and try again.

Offshore Drilling: Spillustrations

SkyTruth is getting barraged by requests from people around the country who want to know what could happen if an incident comparable to the Montara / West Atlas oil spill happened off their coast. In response, we’ve generated a series of illustrations that superimpose the area of oil slicks, as shown on satellite images of the Timor Sea disaster, on various parts of the US including:

These illustrations are not predictive spill models – they don’t take into account local winds, currents, shoreline configuration or bathymetry – but they do accurately portray what a Montara-sized oil slick would look like, as shown on some of the satellite images we’ve been collecting and analyzing for that ongoing event.

Illustration showing hypothetical Montara-sized oil spill off the Virginia coast.

The Montara spill is now in its 45th day, as efforts to drill a relief well continue. Using the oil company’s estimate of 400 barrels per day, over 750 thousand gallons of oil have spilled since the blowout on August 21. Using an alternative estimate of 3,000 barrels per day that is based on the actual published flow rates of nearby oil wells, over 5 and a half million gallons may have been spilled so far.