ECO campaigners have warned that controversial fracking could be used in Dorset to extract oil and gas.
The technique – hydraulic fracturing – is used to released natural resources from the fractures or veins in rock layers.
The West and South Dorset Green Party raised concerns after a Government green light to the principle of using the method. As well as potential earth tremors, the Green Party says it is warning about the possibility of contamination of water supplies.
A spokesman said “Such contaminants include methane and hydrochloric acid that can get into ground water drawn on for mains water supplies.
"Oil is already pumped up in the Wytch Farm and Kimmeridge Bay area of Purbeck and there are a number of existing exploration and production licences in this area.
“As these do not specify the method of extraction, fracking could be used.
“The Green Party has written to the chairman of Wessex Water asking whether they have been told of any proposals or whether they monitor planning applications.
“Also, if water supplies did become contaminated, what they would do about it and what they believe are their legal responsibilities.”
Supporters maintain that fracking – which often involves pressurised fluid being shot through the fractures – can be done safely and is another source of natural energy.
The spokesman added: “The Green Party rejects the idea that the UK should extend its reliance on fossil fuels. “Instead of this dubious fracking option the energy companies should invest in renewable options like wind and tidal energy.”