Pig farmers are seeking retrospective planning consent for a plastics recycling operation near Dalby Forest.

The venture, from RE and SE Gwilliam on the southern edge of the 8,500-acre forest, has seen Allerston and Wilton Parish Council raise concerns over plastic waste blowing across the highly protected designated area and the potential for water supply contamination.

The parish council has issued the criticism in response to a planning application to North Yorkshire Council for a retrospective change of use from agriculture to allow use for agricultural plastics recycling.

Documents submitted with the proposal state following the introduction of regulations making it illegal to burn or bury agricultural plastics, RE and SE Gwilliam diversified their farming business off Malton Cote Road, Ebberston into the recycling of agricultural plastics in 2006.

The papers state while the “main agricultural enterprise” at the farm is pig rearing and finishing, with up to 4,000 weaner and 2,000 fattening pigs, the plastics venture has 400 customers from whom they collect from once annually, resulting in 800 tractor and trailer movements.

The venture runs for up to 44 hours a week and uses an outside hardstanding storage area extending to 1,800sq m and part of a farm building to process the plastic by washing, drying and pelleting, with up to 25 tonnes of pellets being sold every week for the manufacture of recycled plastics.

The application states: “When considering amenity impacts of a development, context is very important. The application site is located within a remote rural area, on the southern edge of Dalby Forest, 4km to the north of Ebberston village.”

Responding to the proposal, Natural England said it would not have significant adverse impacts on protected nature conservation sites or landscapes.

However, Allerston and Wilton Parish Council has called on both the North York Moors National Park Authority and Forestry England, which manages Dalby Forest, to join it in opposing the proposal.

A parish spokesman said: “The area has been a disgrace for years. Not only is it an eyesore, but there is plastic waste everywhere blowing into the forest and sitting on agricultural land.

“There are well documented examples of run off from plastic waste getting into ground water and this could ultimately contaminate Allerston water supply.”

The national park authority said it had no objection to the processing of the waste plastic, but had “significant concerns” about the open storage of plastic waste in an exposed location.

The authority has stated the six-metre high piles of mainly white and reflective plastic stored on the site gave rise to “a substantial visual impact”, including from well-used public rights of way and other open access routes within the national park.

It has highlighted how its joint Minerals and Waste Plan with the council states proposals for minerals and waste development will be permitted where it can be demonstrated that there would be no unacceptable impacts on the amenity of users of public rights of way as a result of visual intrusion.

Nevertheless, the park authority has advised extending screening of the plastic storage area and limiting the height of the piles of plastic would make the development more acceptable.