Environment Report 2018

4.2 Discharged Drill Cuttings Figure 22 shows the distribution of drill cuttings discharged to the sea across UKCS operators in 2017. The amount discharged depends on the number and length of wells a given operator has drilled over the year, and therefore the volume increases during intensive drilling campaigns. On average, 502 tonnes of drill cuttings per well were discharged to sea in 2017 — greater than the 370 tonnes averaged in 2016. Four of the 30 operators discharged oil-based fluid cuttings in 2017, fewer than in 2016. All discharged oil-based cuttings undergo processing and cleaning on-board to bring the oil-on-cuttings content to below 1 per cent. The trend of increased oil-based fluid cuttings being discharged to sea continued in 2017, means fewer cuttings are being shipped to shore for further processing and landfill.

Figure 22: Cuttings Discharged to Sea per Operator, 2017

4

OBM

WBM

14,000

Industry Average 2017

Industry Average 2016

12,000

10,000

8,000

6,000

4,000 Discharged Cuttings (Tonnes)

2,000

0

A B C D E F G H I

J K L M N O P Q R S T U V W X Y Z AA BB CC DD EE

Source: EEMS October 2018

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