Environment Report 2014

ENVIRONMENT REPORT 2014

3. Pipeline Chemicals Chemicals are used to maintain pipelines and ensure pipeline integrity. These include biocides and oxygen scavengers. Discharge of all the above is tightly controlled in the UK under the Offshore Chemical Regulations 2002 (as amended 2011). These discharges are permitted and approved by DECC prior to any discharge, following submission by operators of drilling operations, production operations and pipeline operations applications using the UK Oil Portal. These applications contain a description of the chemicals to be used and discharged, a risk assessment of the impact of any discharges, and any proposed monitoring and/or techniques that will be applied to minimise discharges. 3.3.1 Chemical Discharge Volumes In 2013, almost 131,150 tonnes of chemicals were discharged to sea, of which 79 per cent (103,000 tonnes) were from drilling activities. The total volume of chemicals discharged has varied each year since 2000; this is primarily due to changes in the levels of drilling chemicals discharged.

Figure 4: Chemical Discharges by Activity on the UK Continental Shelf from 2000 to 2013

180,000

Drilling Chemicals

Production Chemicals

Pipeline Chemicals

160,000

140,000

120,000

100,000

80,000

Tonnes

60,000

40,000

20,000

0

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

Source: EEMS June 2014

In general, the volume of drilling chemicals discharged coincides with the levels of exploration, appraisal and development well drilling on the UKCS. Between 2000 and 2010, a period averaging around 93,000 tonnes of drilling chemical discharge per year, an average of over 250 wells per year were drilled on the UKCS. Drilling activity in the UK then dropped; 165 and 175 wells were drilled in 2011 and 2012, respectively. This correlates strongly to the drilling chemical discharges shown in Figure 4 as they also fell to around 67,000 tonnes per year in the same period.

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