Montara oil spill - Operational monitoring studies

Operational 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.

Responsibility for the management of the operational monitoring studies during the Montara incident rested with the Australian Maritime Safety Authority. The focus of operational monitoring is to provide information that assists in planning and executing the response. There are five operational monitoring studies under the environmental monitoring program:

Monitoring of Oil Distribution and Marine and Coastal Megafauna

This study involved monitoring the proximity of oil and response activities to sensitive marine life, commercial activities and key habitats and communities to reduce potential exposure and, if unavoidable, to determine the extent and impact of any exposure.

This study was implemented immediately after the spill occurred. Implementation included daily aerial and water based surveillance and computer modeling using known information about the weather patterns and water movement in the region. For more information see: Montara Well Head Platform, 21 August 2009

Monitoring of Oil Character Fates and Effects

This study involved sampling and analysing the Montara oil to assist responders by providing information on how it behaved once in the water. The results of this study were also used to support computer modeling of the spill. Samples were fingerprinted and analysed and assessments were supported by oil spill trajectory modeling.

Several reports under this study are available at: www.amsa.gov.au/marine_environment_protection/national_plan/Reports-Fact_Sheets-Brochures/.

Shoreline Assessment Ground Surveys

This study aimed to collect information about the habitats, wildlife and plants found on nearby shorelines. This information can then be used to help responders determine how to protect these areas and minimise the impact of any potential exposure to oil. The information can also be used as baseline data to assist future monitoring.

A five day baseline Shoreline Assessment at Ashmore Reef and Cartier Island marine reserves was completed on 25 October 2009. The report from this study is available. The survey was carried out to determine if any hydrocarbons were present within the intertidal areas of Ashmore and Cartier and to provide baseline information about their environments for future surveys.

The field work for a post impact Shoreline Assessment at Ashmore Reef and Cartier Island marine reserves and Browse Island was completed on 15 February 2010. The survey was conducted to determine if the shorelines in these areas had been exposed to oil and, if so, to assist in predicting longer term oil impact, fates and effects. When finalised, the report on the survey will be made available.

Monitoring of Dispersant Efficiency and Fate of Dispersed Oil

This study was implemented to assess and monitor the effectiveness of the chemical dispersant operations during the incident response. The results of this study have been incorporated with the results of monitoring study O2,and can be found at www.amsa.gov.au/marine_environment_protection/national_plan/Reports-Fact_Sheets-Brochures/.

Wildlife impact monitoring

This study aimed to locate, assess and treat oil affected wildlife found in the region. Carcasses of oil affected wildlife were retained and tested to determine their cause of death.

Tests were conducted on four fish specimens collected in the vicinity of the spill. Expert analysis of the specimens showed no oil contamination. The report is available and the results were used to inform the environmental response to the oil spill. Long-term monitoring will include further investigation into the impact of the oil spill on fish.

Tests were also conducted on 16 birds, two sea snakes and one green turtle collected in the region of the oil spill. Although two birds showed signs of exposure to oil, results indicated that the remaining 14 birds were not exposed to oil. These birds appeared in poor physical condition and were likely to have died of natural causes. While the results indicate both sea snakes were exposed to oil there was no evidence indicating the sea turtle had been exposed. The reports on the birds, sea snakes and turtle tests are available. The results were used to inform the environmental response to the incident and future monitoring. The long-term environmental monitoring program will further examine the impacts of the oil spill on birds, sea snakes and turtles.

A team of marine biologists conducted a survey of marine life in the region surrounding the Montara platform and Ashmore islands during the incident. The study was undertaken by three marine biologists to provide a census of birds, whales, dolphins, marine turtles and sea snakes in the area and to identify any impacts to those species as a result of the spill. The report on the survey is available. The results built on our existing knowledge of wildlife in the area and the spill, and has informed ongoing monitoring activity.