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ENVIRONMENT REPORT
2016
Releases by Source
Understanding source trends for past data allows operators to develop plans to target particular operational
areas where accidental releases have been more frequent. There is annual variation in the breakdown of sources,
reflecting the unplanned nature of the releases. There are limited data publically available on the circumstances
leading to particular PON1 reports and so some categories are necessarily broad.
The majority (799 tonnes) of the reported accidental oil releases between 2010 and 2015 came from production
systems and related equipment or pipework infrastructure. However, 754 tonnes (93 per cent) of this came from
just three releases. In 2010, there was one spill of 131 tonnes of crude from a failed subsea sump pump; in 2011,
218 tonnes of crude were released from a pipeline; and, in 2012, 405 tonnes of condensate were released from
a wellbore loss of containment. These masses are the worst case estimations for each incident and so the actual
amount released is likely to be less. Another notable release was that of 56 tonnes in 2013 from a lubricating oil
drain being incorrectly routed to sea.
As previously stated, the majority of releases are very small and so major releases have been shaded in
Figure 26 to be easily identified. The graph shows clearly the significant impact on total mass that these individual
incidents have.
Figure 26: Accidental Oil Release Mass by Source
0
50
100
150
200
250
300
350
0
100
200
300
400
500
600
2010
2011
2012
2013
2014
2015
Number of Releases
Accidental Oil Release Mass (Tonnes)
Hydraulic Systems
Subsea Systems and
Related Equipment
Pipework Infrastructure
Containment
Bulk Transfer Systems
Drainage Systems
Production Systems and
Related Equipment
Other*
Number of Releases
Source: BEIS July 2016
*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