ARCHAEOLOGISTS say there may be prehistoric finds uncovered by new quarrying activities between Bacup and Whitworth.
And developers have been told that any Middle Iron Age discoveries at the Whitworth Quarry Complex must be preserved for observation by Lancashire historians.
County councillors have been told that a buried former land surface has been identified by a carbon dating survey on the site, formed by Briannia, Lee and Facit quarries, which is covered by a layer of peat that did not form until the first century BC. But now county archaeologists believe that any finds will only be of local and regional significance and are only requiring that they be either excavated or recorded, if they are unearthed by miners.
Neighbours had objected to the continuation of gritstone quarrying works at the complex, which has a planning permission until 2042.
In a review hearing, conducted by the county's development control committee, residents heard that quarrying would now be concentrated on the north and west of the 376-hectare site.
People feared that extra noise and dust from blasting would be disruptive and the impact of more lorries along the access roads, Back Cown Lane and Tong End, would be problematic.
And the Ramblers’ Association had also expressed concerns that the quarry operators wanted to extinguish a number of footpaths around the land, rather than divert them.
Planning officer Rob Hope said in a report: "Fortunately the Whitworth Quarry Complex is remote from residential properties and the county planning authority has no history of concerns or complaints in relation to noise, dust or blasting."
No increase in hours had been applied before and the footpath network alterations were acceptable, given the nature of workings inside the quarry, he added.
County councillors approved the quarrying extension, subject to the operational hours of 7am to 7pm remaining, a condition regarding archaeological finds and a restoration scheme to be adopted following mining works.
Around 52 million tonnes of stone, including three main successions, Upper Sandrock, Lower Sandrock and Upper Haslingden Flags remain at the quarry, according to a 2010 survey.