Fracking onshore is no different from fracking offshore. It has been being used at the Wytch Farm oilfield on the Isle of Purbeck for some time without problem.
Yes, of course there have been cases of fracking being done inapropriately and dangerously. It is not, I think, coincidental that this has happened mainly in the coal mining areas of the Eastern USA, where lax legislation has resulted in a shockingly bad safety record and lack of control of pollution in the coal mining areas for decades. Would you ban the consumption of meat in Britain because of the recent problems of horsemeat being discovered in 2% of the products tested?