Environment Report 2016

ENVIRONMENT REPORT 2016

Waste Composition and Disposal Last year, drill cuttings returned to shore were mainly made up of hazardous solids, hazardous oils and other hazardous liquids, such as oily water, with 11 per cent being non-hazardous. Solids and liquids are classified as hazardous if they contain small amounts of oil. Sludges, liquids and tank washings make up over half of wastes from operational and decommissioning activities (56 per cent), with over 92,000 tonnes returned to shore last year. Liquid wastes are generally not separated from one another offshore due to physical space restrictions, giving rise to such a sizeable category. 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 43 . Oil is recovered and usually reused as a fuel source and the cleaned solids are disposed of in a landfill. The offshore industry generated over 4,300 tonnes of scrap metal from decommissioning in 2015, a significant increase on the 2014 figure of 1,900 tonnes, which was all reused or recycled. Over 95 per cent of the total decommissioning waste last year was reused or recycled.

Figure 16: Operational and Decommissioning Waste Generated Offshore by Category in 2015

0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 100,000

Total Disposed Operational Total Disposed Decommissioning

Waste Disposed (Tonnes)

Sludges/ Liquids/Tank Washings

Scrap Metal General Waste Segregated Recyclables

Miscellaneous Special Waste

Oils

Chemicals/ Paints

Drums/ Containers

Other*

*Other includes wastes such as asbestos, clinical waste, construction materials, explosives and radioactive materials

Source: EEMS July 2016

Last year, 98 per cent of waste (216,500 tonnes) was brought to shore in the UK, with just 1 per cent transferred to the Netherlands for processing. The disposal route for 1 per cent of waste was categorised as “not applicable” or was not specified.

43 Anaerobic digestion is the breakdown of biodegradable material by micro-organisms in the absence of oxygen.

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