PTTEP Australasia is reporting that their fifth attempt to kill the leaking well on the Montara platform has succeeded, shutting off the uncontrolled flow of oil, gas, and natural gas condensate that has been polluting the water and air off Western Australia since the blowout occurred on August 21. The fire that ignited over the weekend, engulfing the Montara platform and the attached West Atlas drill rig, has also been nearly extinguished.

Heavy mud was pumped into the damaged well at a point 8,600 feet below the seabed, where it was intercepted by a relief well drilled from the West Triton jackup rig. Towed in from Singapore, the West Triton did not arrive on scene until September 10, nearly three weeks after the blowout occurred. It took nearly four more weeks to set up the rig, drill down to the intercept depth, and make the first unsuccessful attempt to intercept the damaged well. Finally, after 74 days, the spill has been stopped. Difficult tasks ahead: now workers must try to re-enter the well from the fire-damaged Montara platform so they can inject permanent cement plugs. As a PTTEP official notes:

We do not underestimate the significantly increased technical complexity, logistical challenges and hazards of the work now required in the wake of the damage caused by the fire to the wellhead platform and the West Atlas rig.

Estimates of the amount of oil spilled vary widely. PTTEP’s unexplained estimate of 400 barrels per day yields a total of 1,243,200 gallons. The Australian government’s estimate of “up to” 2,000 barrels per day means a total spill of as much as 6, 216,000 gallons. And an estimate of 3,000 barrels per day based on the known flow rates of other wells in the area results in a spill of 9,324,000 gallons, almost as large as the 11 million gallon Exxon Valdez spill that, 20 years after a massive cleanup operation, is still affecting Alaskan communities and the environment.

Spectacular AP video of the platform fire here.