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Mark Hazell's avatar

‘Renewables’ have always been treated differently. Take rock dump. Sometimes when installing pipelines and cables, or even structures offshore subject to scour, you need to dump rock for protection (from trawling, anchor drag or in the case of scour, exposure and weakening of foundations). This is much more of an issue in shallower waters where currents are strongest and trawling etc. more frequent.

Environmentally this is frowned on because you are introducing a foreign material. Rock dump is also well nigh impossible to retrieve on decommissioning so is a permanent change to the seabed.

Historically the oil industry has been under pressure to minimise volumes. This can be done by trenching and burial with ploughs for pipeline and cables sometimes using multiple runs and with careful survey to only dump on difficult sections. In some areas you can instead use concrete mats or structures (some even have features like ‘fronds’ to encourage sediment deposition). Concrete mats and structures can of course also be retrieved at end of field life. All this is very expensive though, particularly as in most cases you will still need to rock dump in certain locations, just a bit less of it.

Rock dumpers by the way are much cheaper than Construction Support and Dive Support vessels which are more exotic beasts with trenching spreads, water jetting kit etc.

All these concerns though seem to fly out of the window on offshore wind developments.

A couple of years ago prior to the 33rd licensing round the oil and gas industry was told there was a risk that development consents might not be forthcoming because the UK was about to breach international ‘commitments’ it had made on rock dump.

Needless to say it wasn’t the offshore oil sector that was the culprit.

If you want to see the scale of the problem just download an Environmental Statement for an offshore wind farm. The schematics showing the cable arrays and protection measures also give you a feel for why fishermen don’t like wind farms.

It would appear that we have a ‘two tier’ approach to environmental protection or should that be ‘two faced’; despite protestations to the contrary political virtue signalling will always trump science.

Little known history's avatar

Sandeel fishing has been banned so we have solved that.

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