Environment Report 2018

ENVIRONMENT REPORT 2018

Oil Releases 2010–17 Reviewing the aggregated data for the period 2010–17 does however provide some indication of the trends. The majority (675 tonnes, 55 per cent) of the reported accidental oil releases during this period came from production systems and related equipment, 94 per cent of which (631 tonnes) came from just three releases. In 2010, there was one spill of 131 tonnes of crude from a failed subsea sump pump; in 2012, 405 tonnes of condensate were released from a wellbore loss of containment; and in 2016, 95 tonnes were released from the produced water system of a platform.

The second-largest category over the period was pipework infrastructure (237 tonnes, 19 per cent), the majority of which was attributable to a single release in 2012 when 218 tonnes of crude were released from a pipeline.

As stated above, most oil releases are very small and so large releases have been shaded in Figure 29 to be easily identified. The number of releases has stayed relatively stable over the period, averaging around 270 releases each year, with a range between 247 and 304, but as the graph shows, the mass released varies much more widely. The average yearly mass released for the period is 158 tonnes, but the range is between 24 tonnes in 2015 and 523 tonnes in 2012. The graph shows clearly that this variation is caused by the significant impact on total mass that individual large-mass release incidents have.

Figure 29: Accidental Oil Release Mass by Source

600

350

Other*

300

500

Subsea Systems & Related Equipment Hydraulic Systems

250

400

Containment

200

300

Pipework Infrastructure Bulk Transfer Systems

150

200

100

Number of Releases

Drainage Systems

100

50

Accidental Oil Release Mass (Tonnes)

Production Systems & Related Equipment Number of Releases

0

0

2010 2011 2012 2013 2014 2015 2016 2017

*Other includes releases from firefighting systems, flare systems, deck washings and unidentified sheen, as well as those releases for which no source is identified. Shading highlights single large spills in that particular category.

Source: BEIS July 2018, Oil and Gas UK

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