Vale council rejected an application by Bridgend-based Coastal Oil and Gas to carry out exploratory drilling for shale gas at Llandow.

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And, there is promise in domestic resources from the application of horizontal drilling and staged frac technologies to tight oil reservoirs.

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And then you subtract from that the burning that has been done with the platform and the oil on the surface with the controlled burn, for example -- the application of dispersants, skimming operations and in situ.

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