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ENVIRONMENT REPORT
2016
Figure 33 shows the sources of releases from the last six years with the single large events removed. A general
reduction in the mass of accidental chemical releases can be seen since 2010. Production systems, subsea systems
and hydraulic systems have contributed the majority over the six years. However, beyond this there is little trend,
which demonstrates the unplanned nature of such releases.
Figure 33: Accidental Chemical Release Mass by Source excluding Outliers
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 Chemical Release Mass (Tonnes)
Hydraulic Systems
Subsea Systems and
Related Equipment
Pipework
Infrastructure
Containers
Bulk Transfer Systems
Drainage Systems
Production Systems
and Related
Equipment
Other*
Number of Releases
Source: BEIS July 2016
*Other includes releases from flare systems, deck washings, fire fighting and those releases for
which no source is identified
Figure 34 opposite provides a more detailed breakdown of release source for 2015. This reveals a slight variation
from the six-year trend with subsea and hydraulic systems being the main contributors while production systems
were responsible for relatively little of the mass accidentally spilled. It is notable, however, that production systems
had the highest number of releases with 87 falling in this category.
Eighteen operators contributed to the 50 hydraulic releases and 13 to the 44 subsea releases. The data, however,
are distorted by the three large releases, two of which contribute 55 tonnes to the subsea category and one release
contributes 45.3 tonnes to the hydraulic systems category. A subsea release of 30 tonnes was monoethylene glycol
from a subsea pipeline joint and the other was 25 tonnes of various chemicals from a subsea well. The hydraulic
release was hydraulic fluid from the failure of a subsea control module. If these large releases are excluded, then
hydraulic systems remain the largest contributor and subsea becomes far less prominent. Pipework infrastructure
and drainage systems are then the next two largest categories.