Pencefn Feeds Ltd Enforcement Undertaking

What caused the pollution in the River Teifi in December 2016?

Pencefn Feeds Ltd had been testing the gas levels required for their new anaerobic digestion plant before it could start generating power.

While this testing was being carried out a pipe between the primary and secondary tanks failed and digestate, the substance produced by anaerobic digestion, entered the river Teifi.

What is an anaerobic digestion plant?

An anaerobic digestion plant breaks down organic matter such as animal or food waste to produce biogas and biofertiliser. This can be a source of renewable energy, with some plants supplying methane to the gas grid, or energy to the power grid.

What damage was caused by the pollution?

Sadly, there was major damage to the river Teifi which is one of the most iconic and important recreational and net fisheries in Wales, and an internationally important Special Area of Conservation for endangered fish such as lampreys, salmon and bullhead.

Our Officers counted 982 dead salmonids in the days following the incident and we estimated losses of approximately 18,000 salmonids over the five miles of river that was impacted.

How did we calculate how many fish died as a result of the incident?

Dead fish were counted by our officers in the days following the incident but not all the casualties will have been found.

Based on expected fish densities predicted by the Water Framework Directive classification tool for fish, we estimate that on a five mile stretch of the river, a potential 18,000 salmonids could have been killed.

Has the polluter been prosecuted?

Following our investigations into the cause of the spill, the landowner responsible, Pencefn Feeds Ltd, has accepted a category 1 harm and negligence offence and offered to pay a £40,000 enforcement undertaking.

  • £15,000 will go to West Wales Rivers Trust for fisheries habitat restoration work
  • £5,000 will also go to the Countryside Alliance Foundation to fund education activities about fish and the local environment for children in the Tregaron area
  • The remaining £20,000 will recover investigation and legal costs relating to the case

What is an enforcement undertaking?

An enforcement undertaking is when polluters accept responsibility and offer to pay for environmental improvements in the areas affected by the pollution, such as improving habitats and water quality.

If the donation is equivalent to the size of a potential fine and the proposed work is acceptable, we can accept the enforcement undertaking offer.

If we decided to prosecute instead of accepting the offer then the money would go to the treasury, not the local environment.

By accepting the enforcement undertaking from Pencefn Feeds Ltd, river and environmental charities will be able to improve fisheries habitats in the Teifi catchment. This includes fencing river banks, developing riverside vegetation and removing artificial blockages to fish migration.

This was a major incident – shouldn’t the polluter have to pay more money?

The amount to be paid is based on the Environmental Sentencing Guidelines which states that the amount must reflect the seriousness of the offence and take into account the financial circumstance of the offender.

You can read the Environmental Sentencing Guidelines online which includes the general principles and categories range for setting a fine.

Why has it taken so long to complete the investigation?

This was a complex case with many companies involved including ComBigaS UK, Hallmark Power Ltd and ComBigaS Denmark.

As well as investigating the incident at the site and overseeing the clean-up operation, we also investigated each company and their roles in the incident. 

This was a very time-consuming process but it’s important to carry out a thorough investigation.

Why are you not taking enforcement action against the other companies involved?

Hallmark Power Ltd were employed as the contractors but no longer exist and therefore no prosecution can be taken against them.

ComBigaS UK were set up by ComBigaS Denmark specifically for the construction of two anaerobic digestion plants in the UK. ComBigaS UK also no longer exist and therefore no prosecution can be taken against them.

omBigaS Denmark has links to the project, it wasn’t directly involved. The company is based outside the UK and not covered by UK law.

Will the river recover from the pollution?

The water quality will have recovered fairly quickly once the polluting discharge was stopped and our investigations at the time of the incident indicated that invertebrates were not significantly impacted.

In terms of the fish population of the Afon Teifi, surveys in the summer of 2017 confirmed the presence of salmon fry and, therefore, we know that some of the salmon eggs that were in the gravel on the base of the river at the time of the incident survived.

Unfortunately, large numbers of brown trout were killed by the incident and although populations of this species will also recover, this will take some time.

Do anaerobic digestion plants need an environmental permit to operate?

Under current regulations anaerobic digestion plants that use certain agricultural materials such as slurry, manure, animal bedding and plant tissue do not need an environmental permit and can operate under what’s known as an exemption from permitting.

Some anaerobic digestion sites may need an environmental permit depending on what waste is being used, its quantities and where the activity is taking place.

Did Pencefn Feeds Ltd have a permit for their anaerobic digestion plant?

At the time of the incident, Pencefn Feeds Ltd was operating under an exemption from permitting because they were using only materials which can be used with an exemption.

Will they need an environmental permit to operate in the future?

Pencefn Feeds Ltd has applied for a Standard Rules Environmental Permit so they can continue to operate and take in agricultural and dairy waste. They have also applied for a permit to spread the waste from the anaerobic digestion plant on land.

We are currently reviewing their application which must demonstrate that they have put in measures to prevent a similar incident from reoccurring. This includes:

  • Constructing a properly engineered secondary containment bund to capture any digestate or effluent in the event of a leak
  • Develop an environmental management system to show how they will run the site and deal with any potential incidents
  • The operator will need to prove that they have, or are in the process of, acquiring technical competence to operate this type of facility

We will not issue a permit if they are not able to prove they can meet the required standards.

If the permit is granted we will be able to regulate the facility and carry out regular compliance inspections. We will also have powers to stop the plant operating if it poses a risk to people or the environment.

If you have any questions about the permit or our permitting process please contact

What are you doing to stop pollution incidents like this happening in the future?

We have carried out over 100 pollution prevention visits to farms in Ceredigion and the Teifi catchment in the past year and these have helped reduce the risk of pollution from farm slurry.

We have also carried out inspections of the other 3 anaerobic digester plants in Ceredigion to ensure that suitable pollution prevention measures are in place. 

However, too many pollution incidents affect our precious rivers. The answer rests with all involved, farmers, landowners, farming unions, anglers, NRW, Welsh Government and so on. It also needs a multi-disciplinary approach. More can be done to reduce the amount of slurry produced on farms – both by the farmers themselves and by developing innovative new technologies.

We have also appointed a team to visit farms all over Wales to provide advice and guidance and to help landowners reduce the risk of pollution from their land getting into our rivers.

Last updated