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Waste is segregated and stored appropriately on offshore installations before transportation to shore where it is
landed at a port. It is then transferred to a licensed waste contractor who organises waste management. Disposal
to landfill is costly and is not sustainable in the long term. Operators segregate wastes to reduce the quantity of
material going to landfill and to maximise reuse and recycling.
The total amount, as well as the type, of waste generated varies from year to year depending on the level of
industry activity in exploration, production, maintenance and decommissioning. Wastes classified as hazardous
only present a risk to the environment if they are improperly managed. Modern disposal and recycling techniques,
such as engineered landfill, incineration and recovery of waste oils, minimise the environmental impact.
Waste Mass
In 2015, around 218,500 tonnes of waste materials were returned to shore from the UKCS. This represents a
15 per cent increase when compared to 2014 (190,000) and continues the general rising trend since the mid-2000s.
The increase in waste in 2015 is largely due to growing operational waste in the form of sludges, liquids and tank
washings from mobile drilling rigs. This could be because of more rigorous reporting, but also well plugging and
abandonment activity, which generates well fluids for disposal, and the growing number of rigs that are being
stacked
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and so need to be cleaned and their tanks emptied.
Meanwhile, the amount of drilling waste has fallen by 23 per cent to under 52,000 tonnes, corresponding to
the decline in drilling activity. The rising decommissioning activity is reflected in an 86 per cent increase in
decommissioning waste. Decommissioning waste is currently a small contributor to the overall figures at just
4,733 tonnes, but this is expected to increase in the coming years
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.
Figure 15: Waste Generated by Offshore Activity
0
50,000
100,000
150,000
200,000
250,000
2010
2011
2012
2013
2014
2015
Waste (Tonnes)
Drilling
Operational
Decommissioning
Source: EEMS July 2016
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Reducing a crew on a rig to either zero or just a few key individuals and storing the rig in a harbour.
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See Oil & Gas UK’s
Decommissioning Insight 2016
at
www.oilandgasuk.co.uk/decommissioninginsight1
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