Environment Report 2016

ENVIRONMENT REPORT 2016

5. Accidental Oil and Chemical Releases The oil and gas industry does its utmost to prevent accidental oil and chemical releases by investing heavily in maintenance to prevent leaks; the provision of physical barriers such as downhole safety valves; and in the development of handling procedures and staff training. Offshore hydrocarbon releases must be reported to the Health and Safety Executive (HSE) and all offshore hydrocarbon and chemical releases that reach the marine environment, regardless of size, must be reported to BEIS through the submission of a Petroleum Operations Notice 1 (PON1). PON1 data are published on the BEIS website 47 and updated regularly. The following analysis is based on the PON1 dataset from 2003 to 2015 and presents an overview of the number and mass (excluding the mass of those releases still classified as ‘under review’) of accidental releases on the UKCS in 2015 and over the past decade. Although the number of releases can appear significant, it is important to note that the UK offshore oil and gas industry is committed to transparency in reporting. All releases to the marine environment, no matter how small, are reportable as a PON1. Given that the releases are unplanned, they cannot always be measured and a worst case estimation is used to determine a release amount. 5.1 Overview from 2003 to 2015 There is no clear trend in the amount of chemicals and oil released to the marine environment over the last 13 years, highlighting the sensitivity of these data to single, low incidence, high mass events, as shown in the blue and grey peaks in Figure 24. There is, however, a marked decline in the amount released accidentally in recent years, with the mass of chemical releases falling sharply since 2009 and oil releases since 2012. 2015 saw the smallest mass of accidental oil released on record on the UKCS at 16.5 tonnes, with no individual releases greater than 2.2 tonnes. The total amount of oil and chemicals accidentally released last year is also small relative to the total mass discharged to sea from assets under permits (see section 3). Many of the categories used to break down these data are dominated by a relatively small number of larger releases. Further analysis has been carried out to categorise PON1 data from 2010 to 2015 by source of accidental releases. Chemical releases have also been analysed by hazard to the marine environment.

47 The BEIS PON1 data are available at http://bit.ly/PON1data

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