Coasts and marine

Montara oil spill

On 21 August 2009 the Montara wellhead platform drill rig owned by PTTEP Australasia suffered a well head accident, resulting in the uncontrolled discharge of oil and gas. The discharge of oil and gas was stopped on 3 November 2009.

The Australian Maritime Safety Authority coordinated the emergency spill response in accordance with Australia's National Plan to Combat Pollution of the Sea by Oil and Other Noxious and Hazardous Substances (the national plan).

The Department of the Environment, Water, Heritage and the Arts (now known as the Department of Sustainability, Environment, Water, Population and Communities) engaged in the response through both a Wildlife Plan of Action and by taking on the role of Environmental and Scientific Coordinator under the national plan.

Montara Commission of Inquiry

On 24 November 2010 the Australian Government released the report of the Montara Commission of Inquiry and the Government's draft response to the report. The Department of Resources, Energy and Tourism is the lead agency. Public consultation on the draft response has now closed. For more information go to www.ret.gov.au/montarainquiryresponse 

Environmental monitoring plan

The Australian Government, in conjunction with the company responsible for the rig, PTTEP Australasia, developed a long-term environmental monitoring program to understand the longer term impacts of the spill on the marine environment. The plan, known as the Monitoring Plan for the Montara Well Release Timor Sea, consists of five operational monitoring studies, which were implemented during the response to the incident and seven scientific monitoring studies.

Implementation of the scientific studies is determined by information provided by the operational studies and components of other scientific studies.

Experts from the Australian Institute of Marine Science, CSIRO and relevant state and territory agencies provided input into the Plan and into its implementation to ensure that the monitoring program is appropriate and robust. The Plan covers both short-term and long-term environmental effects of the Montara oil spill and includes marine life surveys, wildlife and habitat studies, continued water quality testing and shoreline ecological assessments.

Environmental monitoring studies

Disclaimer
The views and opinions expressed in these studies are those of the authors and do not necessarily reflect those of the Australian Government or the Minister for Sustainability, Environment, Water, Population and Communities.

While reasonable efforts have been made to ensure that the contents of these studies are factually correct, the Commonwealth does not accept responsibility for the accuracy or completeness of the contents, and shall not be liable for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the contents of these studies.

Operational monitoring studies

Operational (or Type I) monitoring is undertaken during a response to an oil spill event. It is focused on providing information of use in planning or executing the response and provides data in a time-frame that is usable in that context. The environmental monitoring plan outlines five operational monitoring studies.

Scientific monitoring studies

Scientific (or Type II) monitoring is focused on non-response objectives such as estimating environmental damage and post response recovery. Scientific monitoring studies may be undertaken over extended periods.

Implementation of the scientific monitoring component of the environmental monitoring plan is managed by PTTEP Australasia in consultation with the Department and drawing on the advice of a Technical Advisory Group. Individual studies are undertaken by contracted companies, institutions, government agencies or other parties. The environmental monitoring plan outlines seven scientific monitoring studies.

Recently released reports

Three reports under the environmental monitoring plan have recently been finalised and are now available:

Questions and answers - Montara environmental monitoring - results

Study S6 - Status of seabirds and shorebirds at Ashmore Reef, Cartier Island and Browse Island

What was the aim of the study?

This study aimed to create a robust baseline dataset that will be used in long-term monitoring of seabirds and shorebirds at the Commonwealth Ashmore Reef National Nature Reserve and Cartier Island Marine Reserve, as well as the Western Australian Browse Island Nature Reserve, to determine if the Montara Well release has had any long-term impacts on the bird populations and terrestrial habitats of these reserves. The study also aimed to develop and refine the protocols that will be used for future monitoring, including timing and methods of surveys and analyses, over the next five years.

How was the study implemented?

To create the robust baseline dataset, the study:

  1. Collated and interpreted existing data on seabird and shorebird populations at the three reserves to give a pre-incident dataset.
  2. Undertook a targeted field survey of breeding seabirds and migratory shorebirds to determine their status as soon as possible after the Montara well release was controlled.
  3. Considered long-term data to determine the best statistical analyses to use to detect any population changes.
  4. Used the above information to develop and refine protocols for the ongoing monitoring program.

What did the study find?

There were no signs of oil contamination found during the survey.

The report does not draw conclusions about the long-term effects of the Montara well release; rather, it identifies the potential for long-term impacts on bird populations and establishes a monitoring protocol and a robust baseline dataset to inform ongoing monitoring efforts.

The report also provides detailed information concerning individual seabird species at Ashmore Reef and how aspects of their biology relate to the potential for long-term impacts.

Over the next five years, seabird and shorebird monitoring surveys will continue to be conducted twice a year - in April-May and in November - under the Montara environmental monitoring program.

Study S6 - Montara surveys: Final report on benthic surveys at Ashmore, Cartier and Seringapatam Reefs

What was the aim of the study?

The study aimed to determine whether the coral reefs in the vicinity of the Montara oil spill were impacted by the incident.

How was the study implemented?

This study was implemented some time after the oil had been cleaned up. Therefore, a control site was used to compare surveys of reefs that were in the vicinity of the oil spill with surveys of a reef that were some distance away to determine if there were any differences in coral cover or species diversity. Specifically, the study compared the results of surveys at the Ashmore Reef and Cartier Island Commonwealth marine reserves (167 km west-north-west and 108 km west from the Montara well respectively) with surveys at Seringapatam Reef (296 km south-east from the Montara well).

The study also tested samples collected from each of the three reefs to determine if there were any traces of hydrocarbons in the sediments.

What did the study find?

Coral bleaching was seen at all three reefs. The study found that the bleaching was most likely due to higher than normal sea temperatures, based on temperature data collected during the survey and because highest levels of coral bleaching was found at control site. However; further studies to determine if the oil spill has had any impact on Ashmore and Cartier Reef Reserves' resilience to bleaching are underway.

The study found no signs of recent major disturbance to the coral reefs at Ashmore and Cartier, however, the possible effects of any oil contamination on coral reproduction was not tested during these surveys. Further studies are being conducted to determine if the oil spill had any impact on coral reproduction at Ashmore and Cartier Reef Reserves.

Hydrocarbons were found in sediment samples collected from Ashmore and Cartier Reefs Reserves as well as the control site, Seringapatam Reef. The hydrocarbons found in samples collected from the reserves were positively identified as degraded crude oil which differs from the types of hydrocarbons found at Seringapatam. This finding supports sightings during the incident response of oil residues at Ashmore and Cartier Reefs. Natural hydrocarbon breakdown means that the source of the crude oil found at the reserves cannot be positively identified. Further studies are being conducted to provide more information on the hydrocarbons found in sediment samples at all three reefs.

Study S5 - Monitoring program for the Montara well release, Timor Sea: Final report on the Nature of Barracouta and Vulcan Shoals

What was the aim of the study?

The study aimed to determine the possible impacts the Montara oil spill on offshore coral banks. It also aimed to identify the community make up of the shoals, particularly any differences within and between them. The study was undertaken by the Australian Institute of Marine Science.

How was the study conducted?

The study involved collecting video footage and still images of two shoals in the vicinity of the Montara well. The Barracouta Shoal, 60km north-west of the Montara well and the Vulcan Shoal, 30km south-west of the Montara well were chosen as the results of oil spill trajectory modeling conducted under Study S7.1 - Oil fate and effects assessments: spill trajectory analysis indicated oil had passed over them during the incident.

What did the study find?

There were no obvious signs of a major recent disturbance found at either the Barracouta or Vulcan shoal. The study found that both shoals contain diverse communities of flora and fauna and there are pronounced differences in the abundance of species within and between the shoals. The studies findings provide important baseline information for future monitoring work that will be conducted as part of the Montara environmental monitoring program.

Wildlife plan of action

The Department was responsible for the implementation of a plan of action to help any wildlife that might be affected by the oil spill in Commonwealth waters and to respond to any possible impacts in Commonwealth marine reserves in the region. The Department worked closely with the Australian Maritime Safety Authority and other relevant federal and state agencies to implement the plan of action to help any wildlife that was affected by the oil spill in Commonwealth waters and to respond to any possible impacts in nearby Commonwealth marine reserves. The plan was developed by a wildlife expert from Queensland's Department of Environment and Resource Management who coordinated the wildlife response to the Moreton Bay oil spill.

Report Wildlife: if oil affected wildlife is observed in Commonwealth waters please see below for instructions on how to report the incident. Please report wildlife found in State waters to the Oil Pollution hotline on 08 9480 9924

For more information on the region visit www.environment.gov.au/coasts/mbp/north-west

EPBC Act - national environment law

The then Minister for Environment Protection, Heritage and the Arts, Peter Garrett AM MP, formally exempted the company's use of a floating jack up oil rig to relieve pressure on the leaking oil well under the Environment Protection and Biodiversity Conservation Act 1999. He did this on grounds that it was in the national interest to do so because the consequences of allowing the spill to continue whilst an environmental impact assessment was prepared would have been far worse than any impacts that might arise from actions to stem the flow of oil.

Frequently asked questions

What is the impact to wildlife?

Have birds been affected by the oil spill?

A small number of birds found in the region were affected by the oil spill. The birds were identified as common noddies, brown boobies and sooty terns.

Who cared for the birds after they were found?

Birds found in the region were treated by a qualified wildlife expert on-site at Ashmore marine reserve. The process involved capturing the animal, stabilisation and providing onsite care; birds that required additional care were transferred to a veterinary clinic.

The Australian Government and the Western Australian Government established a joint wildlife response centre at Broome. A suitable site was identified and prepared. Fortunately this centre was not required.

What happened to the animals after rehabilitation?

Rehabilitated wildlife recovered from the ocean were released back into the wild once wildlife experts considered them fully recovered.

What other wildlife was affected?

There were two confirmed reports of oil affected sea snakes and one green turtle collected in the vicinity of the oil spill.

No other confirmed reports of affected wildlife were received despite extensive aerial and water-based patrols in the area. There were no confirmed reports of oil affected whales or other cetaceans. There is no available evidence at this time to suggest that the migratory or breeding patterns of any wildlife have been affected. This will continue to be monitored in the long term.

What was the impact on ocean foods (e.g., seagrass) on which fish, birds and animals feed?

There are no seagrasses known to be in the immediate vicinity of the oil spill. However, the Australian Government, in conjunction with the company, is undertaking a number of steps to assess the impact of the oil spill. These assessments will provide a clear picture of the impact of the spill on the marine environment.

How can the public help?

Who should I contact if I find oiled wildlife?

If you observe oiled wildlife or habitat, contact the relevant state environment agency immediately. Instructions will be given over the phone to suit the specific situation.

If people in WA observe oiled wildlife in a coastal area they should immediately call WA's Oil Pollution hotline on 08 9480 9924.

Information that is useful in responding includes:

Information updates

Montara Well Head Platform information and updates
Australian Maritime Safety Authority
www.amsa.gov.au