The agency said the operator was in the process of installing additional gas extraction measures and cladding to seal the site.

BBC: Work under way at Milton Keynes landfill to combat odour

In order to do this the company needs to hermetically seal the drives to prevent He gas leakage over the life of the drive no mean feat.

FORBES: Rare Gases and Fine Lines

The authors argue that even quakes that are imperceptible to humans can damage the caprock seal of CO2 repositories enough to release the gas back into the atmosphere.

ECONOMIST: Carbon capture: Going underground | The

Mr Critchlow said a technical bulletin was issued to gas engineers more than 18 months before the tragedy instructing them to cut off the base of the grill seal with scissors.

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