Fracking is a technique used to release gas and oil from shale rock.
- It involves drilling down before fracturing layers of rock using a pressurised liquid.
- Water, sand and chemicals injected into the rock then allow gas to be released.
- The process enables petroleum, natural gas and other substances to be extracted.
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Outbreaks of light rain or drizzle expected around the coast and hills.
Mike and Cynthia from Ystradgynlais flew out to the German city for a weekend away.
Fine and dry at first but becoming largely cloudy with outbreaks of rain or drizzle.