Environment Report 2015

ENVIRONMENT REPORT 2015

5. Accidental Oil and Chemical Releases 5.1 Introduction

The oil and gas industry does its utmost to prevent accidental oil and chemical releases by investing heavily in the provision of physical barriers, such as downhole safety valves, maintenance to prevent leaks, as well as in the development of handling procedures and staff training. Offshore hydrocarbon (oil and gas) releases must be reported to the Health and Safety Executive (HSE) and all offshore hydrocarbon and chemical releases, regardless of size, that reach the marine environment must be reported to DECC through the submission of a Petroleum Operations Notice 1 (PON1). PON1 data are published on DECC’s website 45 and updated regularly. The following analysis is based on the PON1 dataset 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 2014 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; the amount actually released is often lower than that reported. 5.2 Overview from 2003 to 2014 There is no clear trend in the amount of chemical and oil releases to the marine environment over the last 11 years, highlighting the sensitivity of these data to single, low incidence, high mass events, as shown in the blue and red peaks in Figure 26 opposite. 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 2010. 2014 had the smallest mass of accidental releases on record, with no individual releases greater than ten tonnes of oil or 200 tonnes of chemicals. The total amount of oil and chemicals accidentally released on the UKCS in 2014 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 2014 by source and cause of accidental releases, as well as by hazard to the marine environment for the chemical releases.

45 The DECC PON1 data are available at http://itportal.decc.gov.uk/eng/fox/pon1/PON1_PUBLICATION_EXTERNAL/viewCurrent

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