Fracking for shale gas can go ahead for the first time in the UK since it was linked with earthquakes in 2011.
Energy firm Cuadrilla has drilled two wells at its site in Lancashire after being given the go-ahead to extract shale gas by the government in 2016.
Campaigner Bob Dennett tried to prevent work starting, arguing in the High Court Lancashire County Council failed to properly assess any safety risks.
But Mr Justice Supperstone said there was "no evidence" to support the claim.
Cuadrilla chief executive Francis Egan said he was "delighted" and fracking would start on Saturday.