A Tregaron farm has dismissed claims the Afon Teifi remains exposed to pollution threats from a manure-converting plant which killed an estimated 18,000 fish in 2016.

Fish Legal – a water protection charity – is concerned the aerobic digestion plant, including a slurry tank, responsible for the major pollution incident is still operating without planning permission.

In December 2016, approximately 44,000 gallons of animal waste leaked into river from the facility at Pencefn Dryscol farm near Tregaron.

The charity claims it killed an estimated 18,000 fish on a five-mile stretch of the highly protected river, the longest in Wales.

Six months later, the operator of the facility submitted an application to Ceredigion County Council for retrospective planning to retain the plant.

Despite being in receipt of the application for over five-and-a-half years, the authority is yet to make a decision on whether to grant full planning permission for the industrial site.

Fish Legal claims regulator Natural Resources Wales (NRW) initially said it would not agree to the plant operating until it had planning permission. It adds that the plant owner advised NRW on 5 March 2018 that the facility was not operational yet a site visit carried out by officers a year later found it was.

The regulator subsequently issued an environmental permit for the facility, despite raising ‘significant’ concerns about pollution risks from the ‘proposed development’ with the county council on at least three occasions since 2017, according to documents published on the council’s website. Fish Legal objected to the planning application.

Head of Practice at Fish Legal Penelope Gane said: “Between Ceredigion County Council and NRW, there are huge gaps in terms of planning, regulation and enforcement of this anaerobic digestion facility, leaving the river vulnerable to further pollution. Not only is there a continuing threat to wildlife from another catastrophic failure at this site but the impact of spreading of digestate in the catchment of a Special Area of Conservation (SAC) river which is currently failing its phosphate targets has not been properly considered.”

Geraint John Planning told the Cambrian News on behalf of the farm that planning permission should be granted imminently. It has been operating with an Environment Agency permit. He added that the plant has been redesigned so no repeat pollution incident could occur.

A Ceredigion County Council spokesperson said: “A retrospective planning application was submitted for the retention of Anaerobic Digester Plant including digester and slurry tank and related developments in 2017. This is a complex planning application for development that was completed without planning permission. The last part of the planning process has been to undertake an ‘appropriate assessment’ prior to issuing a decision. Subject to this being confirmed as acceptable a planning permission is expected to be issued shortly.”

NRW Mid Wales Operations manager Ann Weedy said: “NRW has previously raised issues about this planning application and we needed more information to ensure that we can consider the likely environmental effect of the proposal. We are currently considering the application and will respond to Ceredigion County Council.”