Environment Report 2014

3. Emissions and Discharges Offshore 3.1 Introduction

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In 2013, 524 million barrels of oil equivalent (boe) were produced on the UK Continental Shelf (UKCS), satisfying about 50 per cent of the UK’s oil and gas demand 2 . As with all processes to generate fuel and energy, hydrocarbon exploration and production and subsequent facility decommissioning result in discharges and emissions to the environment. These discharges and emissions include atmospheric emissions, produced water, drill cuttings, chemical discharges, waste and accidental releases. In the UK, European and national legislation tightly control discharges and emissions offshore, through a permitting process. To comply with these requirements, operators must consider the potential effect of the discharge or emission on the environment as part of their permit application, which is reviewed and approved by the Department of Energy & Climate Change (DECC) as the regulator. The industry closely monitors discharges and emissions and submits data to be recorded in the Environmental Emissions Monitoring System (EEMS) database. Oil & Gas UK has supported the EEMS database since 1992 and DECC uses it to help meet its national reporting requirements to Europe and the OSPAR Commission 3 . This chapter analyses the aggregated EEMS data from operators for the period 2000 to 2013 for atmospheric emissions, produced water, chemical discharges and waste. The EEMS data was extracted in June 2014 and, this year, Oil & Gas UK has carried out additional analysis on the 2013 data and sought clarification from individual operators on specific data entries where necessary. This supports our ongoing objective to enhance EEMS data quality. 3.2 Produced Water Produced water is water that comes to the surface with hydrocarbons during production. This can be water naturally trapped in the subsurface reservoir or water injected into the reservoir to help lift oil to the surface. Produced water is separated from oil and gas in the first stages of processing and then treated and discharged to the sea. It forms the largest permitted discharge and is the greatest volume of fluid handled offshore. Operators obtain approval for produced water discharge through an oil discharge permit under the Offshore Petroleum Activities (Oil Pollution Prevention and Control) Regulations 2005, which must be applied for using the DECC UK Oil Portal 4 .

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2 See DECC’s DUKES 2014 Statistics www.gov.uk/government/statistics/digest-of-united-kingdom-energy-statistics-2014-internet-content-only 3 The OSPAR Commission aims to protect and conserve the North East Atlantic and its resources. See www.ospar.org 4 The UK Oil Portal allows operators to apply for and receive consents and permits. See https://itportal.decc.gov.uk/eng/fox/live/PORTAL_LOGIN/login

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