The operator of a huge new recycling plant built without planning permission wants to increase the amount of waste it will process by 100,000 tonnes a year.

The facility at the Shelford landfill site in Canterbury is not yet up and running as owner Valencia Waste Management has yet to secure the approval of Kent County Council (KCC) and a permit from the Environment Agency (EA).

But as it awaits a decision on the plans, bosses have now submitted a bid to hike the volume of waste going through the plant annually by 66%, to a quarter-of-a-million tonnes.

It comes amid much controversy over the acre-sized development, which has been built in a different location on the site and on a bigger scale than originally planned, so requires new permission.

Called a materials recycling facility (MRF), Valencia says it will process trade and domestic waste coming into the site to extract recyclable material such as metal, plastic, wood and glass that would otherwise end up in landfill.

A retrospective planning application for the facility, which stands 11.5 metres high and covers an area of more than 4,000 square metres, is still being considered by KCC, but Valencia is now seeking to amend its environmental permit application.

In papers submitted to the EA, it says it wants to increase the tonnage processed by the MRF from 150,000 to 250,000 a year.

We have reviewed the Shelford application and believe we will be able to process more material per annum than the 150,000 tonnes per annum (tpa) stated in the current permit application...

Valencia says experience at its other sites has shown similar MRF systems can cope with a significant increase in volume.

But the bid has sparked fresh concerns about an increase in lorries coming to and from the Shelford site, as well concerns over noise and smells caused by the operation.

Valencia says: “In the last two months, Valencia Waste Management Limited commissioned two facilities, at Dunbar and Heathfield, with similar operations and objectives to the Shelford MRF facility.

“In both operations, the speed the material can be processed, and the recycling rates have been higher than we originally expected.

“As a result, we have reviewed the Shelford application and believe we will be able to process more material per annum than the 150,000 tonnes per annum (tpa) stated in the current permit application.

“We do not believe the increase to 250,000tpa at this stage will change any of the environmental impacts that have already been assessed and mitigated in our current permit application.”

The company also claims the changes will not result in any additional lorry movements, adding that there will be stringent measures to reduce any smell and noise.

It says: “We are aiming for recovery rates of up to 30% of material. So, by making this change, it should generate an additional 30,000 tonnes of recycled material a year, up to a total of 75,000 tonnes.”

But environmental campaigner Magz Hall, who is course director at the School of Creative Arts and Industries in Canterbury, fears it will lead to more pollution.

“It’s very concerning that Valencia wishes to increase capacity, bringing more untreated commercial waste to the Shelford site,” she says.

“Ultimately, this means more pollution overall and does not fit in with Canterbury City Council’s plans for a greener more sustainably focused city.”

Dr Hall has launched a petition on Change.org, now signed by almost 400 people, calling for the scheme to be halted.

“The planning application is entirely inappropriate as the existing commercial landfill site has longstanding emission issues,” she says.

“The plans do not fully consider health implications of pollution from additional lorries, dust, noise, air and water table pollution and potential fire hazards at the site in the evidence it has provided.

“The existing issues of longstanding emissions should be the priority, rather than introducing additional new potential hazards without independent evidence to fully back it up.”

The fresh permit application is out to public consultation until Wednesday, May 8.