Environment Report 2016

ENVIRONMENT REPORT 2016

Just over 31,000 tonnes of water-based fluid cuttings and around 10,000 tonnes of treated oil-based fluid cuttings were discharged from offshore installations on the UKCS in 2015. This is approximately 5,500 tonnes less than was discharged in total the previous year, reflecting the decline in cuttings generated due to reduced drilling activity. The peak in cuttings discharged in 2013 in Figure 7 is due to more complex wells being drilled and is out of step with the general downward trend in drilling. Over 10,000 tonnes of oil-based fluid cuttings were also injected back into the reservoir (compared with 7,400 tonnes in 2014), which means the amount returned to shore last year declined from 82 per cent of the total oil-based fluid cuttings to 76 per cent in 2015.

Figure 7: Drill Cuttings Discharged to Sea

70,000

Cuttings from Oil-Based Fluids Cuttings from Water-Based Fluids

60,000

50,000

40,000

30,000

20,000

Cuttings Discharged to Sea (Tonnes)

10,000

0

2010

2011

2012

2013

2014

2015

Source: EEMS July 2016

Norske Olje & Gas reported a 13 per cent reduction in water-based fluid cuttings discharged to sea on the Norwegian Continental Shelf to just under 100,000 tonnes in 2015. Injection of oil-based fluid cuttings increased from 29 per cent of total oil-based fluid cuttings in 2014 to 33 per cent, while 2,460 tonnes of oil-based fluid cuttings were discharged to sea.

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