Knowledge Centre
Additional Surveys and Wide Area Impact Monitoring Studies
Introduction
Early in the 2000s, the Oil and Gas Industry Marine Monitoring and Assessment Committee was established to ensure that adequate environmental data was available to support the offshore licensing and permitting regime.
In addition to the comprehensive review of UK offshore oil and gas environmental surveys, the committee commissioned two surveys to investigate long-term trends in contaminant persistence and biological recovery of the seabed around a number of established fields.
2004: single well surveys
In 2004, three single wellsites drilled in the early 1980s with different mud systems (water based mud (WBM), low toxicity oil based mud (OBM) and diesel OBM) were surveyed. These sites had been last surveyed in 1987 on behalf of UKOOA. The 2004 survey objective was to investigate the longer term fate and effects of cuttings piles at multi-well developments.
2005/2006: platform specific surveys
Surveys were undertaken in 2005 and 2006 with the objective of investigating changes and recovery of the seabed around a number of producing fields selected on the basis of good long term monitoring data sets. Surveys were undertaken at Alba (in 2005), Beryl, Brae, Murchison and Nelson (all in 2006). The sampling and sample processing methods used were compatible with those used in previous operator surveys.
Wide area impact monitoring studies
Historically, seabed environmental surveys in the context of offshore oil and gas operations have generally been conducted in a localised area around offshore installations. As a consequence, there was much uncertainty regarding the extent of seabed sediment impacts beyond the vicinity of the platform. In response to this area of uncertainty the committee initiated a seabed monitoring programme designed to provide the information required to fill perceived gaps in knowledge. This work uses a wide area, stratified random sampling strategy developed by the Fisheries Research Service (now Marine Scotland) in the Fladen Ground (surveyed in 2000 and 2001) and the East Shetland Basin (surveyed in 2002) to investigate potential far-field environmental impacts. To date, surveys have been undertaken as follows:
- 2005: Fladen Ground
- 2007: East Shetland Basin Survey
- 2008: Irish Sea Survey
- 2009: Central North Sea
