Purpose

At the second WGWAP meeting, held in St Petersburg between 15-18 April 2007, Sakhalin Energy informed the Panel of its intention to undertake a 4-D seismic survey for the Astokh portion of the Piltun-Astokhshoye field. The primary purpose of the survey is to characterise oil and gas deposits and how these have changed since extraction began in 1999. Survey results provide a basis for more efficient drilling, which lowers the risk of certain environmental effects by reducing the number of wells drilled. 

Sakhalin Energy’s preliminary plans for carrying out a 4D seismic survey in the vicinity of the Molikpaq during the summer of 2008 were presented and reviewed by the WGWAP during its meeting in St Petersburg (WGWAP-2) in April 2007.

The primary concern with respect to the proposed seismic survey is ensonification of the gray whale feeding area by sound energy from the airgun pulses. To provide input to Sakhalin Energy’s Environmental Impact Assessment (EIA) for the proposed 2008 seismic survey, the Panel agreed to establish a Seismic Survey Task Force (SSTF) and its terms of reference were established (see section 12.2 of WGWAP-2 2007).

1st Meeting (The Hague, 25-28 June 2007)

The SSTF held a workshop in order to:

  • Review and analyze noise predictions and estimated whale densities for the proposed 2008 Astokh Seismic Survey in the context of potential effects on the western gray whale (WGW) population;
  • Develop recommendations for mitigating the impacts of the survey on gray whales;
  • Develop recommendations for gray whale monitoring during the survey to both minimize effects on the whales in “real time” and contribute to scientific knowledge regarding the effects of seismic surveys on whales. These recommendations will be aimed at helping to ensure that the effects of this and any future seismic surveys offshore Sakhalin are minimized.

The workshop reviewed and analyzed, as a contribution to the EIA, noise predictions and estimated whale densities for the proposed 2008 Astokh seismic operations in the light of potential effects on gray whales, and made recommendations on mitigation and monitoring. SSTF-1 Terms of Reference

2nd Meeting (Lausanne, 13-16 March 2008)

The report from the first meeting of the SSTF was considered at WGWAP-3 in Lausanne, Switzerland in November 2007. Also at that meeting, Sahkalin Energy announced its decision to postpone the Astokh seismic survey to the summer of 2009. The WGWAP and Sakhalin Energy therefore agreed to convene a second SSTF workshop, with updated terms of reference, to build on and complete the work of the first workshop. SSTF-2 Terms of Reference

3rd Meeting (Vancouver, 31 January - 2 February 2009)

At it fourth meeting, the WGWAP concurred with the SSTF that a suitable group of experts should be asked to work with Sakhalin Energy scientists to develop a fully specified field plan and proposed analysis, well before the final plans for monitoring in 2009 are completed. At the fifth WGWAP meeting it was decided that this should take the form of a SSTF workshop extended with outside experts in relevant fields. SSTF-3 Terms of Reference

4th Meeting (Geneva, 6-8 December 2009)

The aim of this meeting was to resolve outstanding issues in preparation for the Astokh 4-D seismic survey scheduled for June-July 2010.

5th Meeting (Geneva, 13-14 April 2010)

As this was to be the last meeting of the task force before the 2010 Astokh 4-D seismic survey, the primary goal was to ensure that all outstanding issues regarding the monitoring and mitigation plan were considered and resolved to the extent possible.

6th Meeting (Geneva, 29 Nov - 01 Dec 2010)

As this was the first meeting of the SSTF since the 2010 Astokh 4-D seismic survey, the primary aim of the meeting was to review the conduct of the survey, examine preliminary results and consider plans for future analyses. In addition, the SSTF had been asked to consider plans for a 2-D seismic survey proposed by Sakhalin Energy for summer 2011.

7th Meeting (Geneva, 10-11 May 2011)

At this meeting, the main work of the Task Force was to review progress on recommendations made at SSTF-6 and WGWAP-9. In particular, the objectives were to: examine any results from the recommended priority analyses for the 2010 survey; develop a workplan for completing the analyses; and develop mitigation and monitoring plans for the South Piltun 2-D survey scheduled for 2011.