The HSE investigation focussed on the possibility of a faulty gas distribution system and found the cast iron mains pipe was sunk in sandy-gravelly soil that was classified as "very aggressive" to "moderately corrosive".

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This may seem unremarkable, but what it really means is the soil is gravelly and complex.

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This is achieved due to its soil, which sits on a gravelly plateau where the vines have to dig deep to extract the nutrients.

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