At approximately 5.30 a.m. Australian Western Standard Time (AWST) (7.30 a.m. Australian Eastern Standard Time [AEST]) on Friday 21 August 2009, the Montara Wellhead Platform located 140 nautical miles (approximately 260 kilometres) offshore from the northwest Australian coast, had an uncontrolled release of hydrocarbons from one of the platform wells through its West Atlas oil rig. Consequently oil escaped to the surface and gaseous hydrocarbons escaped into the atmosphere. [10] The Montara oil and gas field is located in the northern territory in the concession block AC/RL3 650km west of Darwin in the Timor Sea, off northern Australia. Montara has recoverable reserves of 24 million barrels and is expected to produce 35,000bopd of light, low-sulphur crude. The field is located in about 80m of water and has a 10m oil column and a 25m gas column. Montara has four oil-producing wells, including a gas re-injection well and its production life is estimated to be 12 years. Montara was first discovered in March 1988 by BHP Billiton. Australian oil project developer Coogee Resources took over as the operator of the field in September 2003. In December 2008, PTT Exploration & Production, a Thailand-based state-owned petroleum and natural gas explorer, acquired Coogee for $170m. The company was renamed as PTTEP Australasia (PTTEP AA). The deal gave PTTEP 100% control over the Montara development project, which includes Montara, Skua, Swift and Swallow fields. A total of ten wells, nine oil producers and one gas injection well are part of the Montara development project. [14] The spill continued until 3 November 2009, when the well was capped by a relief well. In total, approximately 64 000 litres of oil per day leaked from the well from 21 August 2009 until 3 November 2009, a total of 106 days. In total, approximately 6.7 million litres of oil leaked from the well, enough to fill nearly 3 Olympic-size swimming pools. [11] The Montara oil spill is the largest offshore spill in Australian history. To control the spill, The clean-up was apparently no less dangerous, with the Australian Maritime Safety Authority (AMSA) applying more than 184,000 litres of dispersants on the oil on sea surface. Some of these dispersants are known to be toxic and carcinogenic to human life. Two of the dispersants –Corexit 9500 and Corexit 9527A–have since been found by scientists to amplify the toxicity of oil 52 times. Only one of those dispersants is approved for use in Australian waters. Since the spill, communities in the Indonesian province closest to Australia, East Nusa Tenggara, have continued to protest that damage has been caused to their communities and economy. |