Fracking plans spark oil and gas well warning
25 March 2014 Last updated at 06:54 GMT
The UK must learn from leaks and poor monitoring at existing onshore oil and gas sites before any expansion of shale gas "fracking", scientists have warned.
A review of 2,152 wells drilled from 1902-2013 found up to 100 "orphaned" wells for which no firm is responsible.
The long-term stability of wells and the risk of pollution are key considerations if the coalition pushes ahead with plans to expand the shale gas industry.
John Moylan reports.