Press release

Anaerobic digestion plant to pay £20,000

Poor site management at an anaerobic digestion (AD) plant in Hockliffe, Bedfordshire led to 3km of watercourses being polluted.

The overflowing tank
The overflowing tank

Trinity Hall Biogas Ltd leased the farm land to run the AD plant and owned the operation.

On 15 June Luton Magistrates’ Court fined the company £10,000 and ordered it to pay £10,423.79 Environment Agency costs after it pleaded guilty to the offences.

Warren Scott, aged 44, of Owles Lane, Buntingford, Hertfordshire, the controlling partner of Scott and Scott, the business operating the plant, accepted a caution at a previous hearing.

The court heard that as a result of overflows from the plant in December 2013 and again the following April, water quality was chronically affected in the stream from the farm near Hockliffe to the Ouzel Brook approximately 3km downstream..

Ms Wendy Foster, prosecuting for the Agency, said that Scott had reported an overflow of effluent from a storage container at Trinity Hall Farm between Hockliffe and Dunstable. It had flowed into a nearby ditch which eventually ran into the Ouzel Brook.

The storage container held liquid which had leached from a maize heap stored as bio-fuel for an anaerobic digestion (AD) plant. The tank had not been checked and had overflowed.

Ms Foster said bags of wrapped bio-fuel, owned by the company, were stored on a field in rows, the ends of which were within 10m of the ditch where the effluent had been found. This is a breach of silage regulations.

She said samples of bacterial growth taken from the watercourse indicated an ongoing chronic pollution.

Four months later Agency officers went back to the farm to check the water quality of the brook and nearby watercourses and found levels of ammonia at 10milligram a litre, 10 times higher than normally found in similar watercourses.

Ms Foster said:

Any concentration in excess of 5 milligram per litre is likely to have a toxic effect on aquatic life.

The effluent in the tank was only inches from the top and a mud bank had been cleared creating a direct pathway for effluent to reach the watercourse. Effluent was leaking from a pump in several places and running into a ditch.

The company told Agency investigators that Scott and Scott were the day to day operators of the AD Plant and were only responsible for emptying the tank if there was an agreement with the company for them to do so. There were no such agreements at the time of the offences, this was an oversight by the company.

Ms Foster said the site had been ‘poorly managed’ rather than the pollution being an isolated incident.

The offences arose out of negligence of the defendant company. The repeated incidents of pollution and failures to comply with regulations are indicative of inadequate systems and monitoring rather than an isolated incident.

The company said it had reported the incident and had since put in place infrastructure to prevent any further offences.

The District Judge hearing the case said:

Self-reporting the incident was a substantial mitigating factor – the pollutions impacted upon 3km of the watercourse. It is incredulous that there was no system in place to empty the tank.

After the hearing Environment Agency officer Kat Wynn said

Given that the tank was close to nearby ditches it was reasonably forseeable that any overflow would cause pollution. Operators of businesses that store polluting effluents should have rigorous procedures in place to minimize the risk of an overflow or leak occurring.

Regulations are there to follow and guidance for similar operations can be found on the gov.uk website at https://www.gov.uk/guidance/storing-silage-slurry-and-agricultural-fuel-oil

Anyone unsure about setting up a similar business should seek proper advice from their local Environment Agency Land and Water team here.

Trinity Hall Biogas Ltd pleaded guilty to:

  1. On or about 4 December 2013 you did cause a poisonous, noxious or polluting matter to enter inland freshwaters, namely the Ouzel Brook, at Hockliffe, Bedfordshire without being authorised by an environmental permit. Contrary to regulations 12(1)(b) and 38(1)(a) of the Environmental Permitting (England and Wales) Regulations 2010

  2. On or about 4 December 2013 being a person who has custody or control of silage that was being made or stored you failed to ensure that the silage was placed at least 10 metres from an inland freshwater in accordance with Regulation 3(1)(C)(ii) of The Water Resources (Control of Pollution) (Silage, Slurry and Agricultural Fuel Oil)(England) Regulations 2010.
    Contrary to Regulation 10(1) of The Water Resources (Control of pollution) (Silage Slurry & Agricultural Fuel Oil) (England) Regulations 2010

  3. On or about 22 April 2014 you did cause a poisonous, noxious or polluting matter to enter inland freshwaters, namely unnamed tributaries of the Ouzel Brook, at Hockliffe, Bedfordshire without being authorised by an environmental permit. Contrary to regulations 12(1)(b) and 38(1)(a) of the Environmental Permitting (England and Wales) Regulations 2010

  4. On or about 22 April 2014 being a person who had custody or control of silage that was being made or stored you failed to ensure an effluent tank and pipe was situated at least 10 metres from an inland freshwater in accordance with 3(1)(a) and schedule 1(6) of The Water Resources (Control of Pollution) (Silage, Slurry and Agricultural Fuel Oil)(England) Regulations 2010. Contrary to Regulation 10(1) of The Water Resources (Control of pollution) (Silage Slurry & Agricultural Fuel Oil) (England) Regulations 2010

Published 30 June 2016