The decision to refuse a highly controversial 100-acre quarry in Ottery St. Mary will come before an appeal in October.

Devon councillors refused the application for Straitgate Farm on Exeter Road last December, following significant concerns about the safety and environmental impact of the project.

Council officers had recommended approval for the plans which would have seen up to 1.5 million tonnes of sand and gravel dug up at the site over the course of 10 to 12 years. The materials would have then been transported 23 miles by road to Hillhead Quarry near Uffculme in Mid Devon for processing.

Despite years of attempts to get the plans in a state thought to be acceptable to the council's development management committee, when it came to the vote councillors rejected the plans by five votes to three and instead backed a motion of refusal.

Their reasons included potential harms on 'heritage assets' such as Cadhay House, the unacceptable impact on human health because of potential dangers to the water supply, lack of evidence of measures for protected species, and lack of a surface water management plan and subsequent potential flood risks.

Councillors also cited the loss of mature trees and hedges, while there were worries about the quarry's impact on climate change – partly as a result of the 23-mile journey extracted materials would be hauled along the county's roads in HGVs.

However, Aggregate Industries UK Ltd, a Leicestershire-based building material manufacturer and supplier, is now appealing the decision.

In a statement, it said: "Aggregate Industries can confirm it has appealed the decision by Devon County Council to reject its planning application for the extraction of sand and gravel – as part of the Devon Minerals Plan – at Ottery St Mary.

"The site is of particular significance as it will reduce the reliance on importing aggregate materials into Devon. The proposed quarry, if permitted, will support jobs and provide essential construction materials into the local market."

Local county councillor Jess Bailey (Independent, Otter Valley), a vocal campaigner against the quarry, reacted by saying: "I have always opposed the application for this 100-acre quarry and I intend to vociferously oppose the appeal by Aggregate Industries.

"The proposed quarry is terrible news for our local communities and the environment. I hope that the inspector upholds the many compelling reasons for refusal and rejects this highly damaging application once and for all."

Ottery St Mary Town Council also reiterated its opposition to the plans at a recent meeting.

The planning inquiry into the decision is slated to begin on Tuesday 4 October.