Environment Report 2019

Figure 22: Waste Generated by Offshore Activity

300,000

Decomissioning Operational Drilling

250,000

200,000

3

150,000

Waste (Tonnes)

100,000

50,000

0

2010

2011

2012

2013

2014

2015

2016

2017

2018

Source: EEMS May 2019

Waste Composition and Disposal Wastes are processed to separate hydrocarbons and heavy metals from solids and other liquids. The liquids are then treated for safe discharge to the sewer system, while the remaining materials can be used in renewable energy facilities such as anaerobic digesters. Oil is recovered and usually reused as a fuel source and the cleaned solids are disposed of in a landfill. Sludges, liquids and tank washing make up the largest category of waste (22 per cent) disposed of in 2018. This category includes the backload of drilling muds. In comparison with 2017, there was a 56 per cent decrease in waste produced from this stream. Comprising over half of total waste returned to shore, liquid wastes are generally not separated from one another offshore due to space restrictions, giving rise to such a sizeable category.

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