Shale gas operator Cuadrilla has submitted plans to change the type of fracking fluid it uses at its Preston New Road site.
The firm, which has paused operations at the site since before Christmas, wants to use a whole new raft of additives to the fracking fluid which is injected under pressure deep underground to release the gas to be collected.
The Environment agency has opened a public consultation on the bid which runs until March 20.
Nick Mace, environment manager at Cuadrilla said the firm had varied the permit before. He said: “The reason for the proposed variation is that we’d like to modify our fracturing fluid so that more sand can be carried into the shale rock with the water when we re-commence hydraulic fracturing operations at the Preston New Road site.
“To do this we propose to add some chemicals which have already been approved for use elsewhere in the UK by the Environment Agency.
“The fracturing fluid will remain non-hazardous to groundwater, as it must do under UK regulation, and additional additives we are proposing to use are commonly found in food, toiletries and other products used around the home.”
But fracking opponents Frack Free Lancashire said: “We are concerned, but not entirely surprised, that after years of claiming that the only two chemicals to be used in UK fracking were polyacrylimide and hydrochloric acid, that they should now be seeking, after just one failed frack, to expand the list of chemicals.
"Equally concerning is the list of 41 potential additives to their drilling fluids of which no less than 14 are described by Cuadrilla themselves as “potentially hazardous”.
A spokesman from the Preston New Road Action Group said it was another attempt to change bit by bit, regulations that had been put in place to maintain safety.
They said: “It feels as though we are being fracked by trial and error: this seems like another desperate attempt to resurrect this dying industry.
“How will changing the fracking fluids prevent seismic events? Just more worry for the unfortunate guinea pigs living close to the site.”