Two years ago, Environment Agency (EA) officers were alerted to pollution on the river Mole, near South Molton, Devon. They found more than 9,000 dead salmon, brown trout, sea trout, bullheads, stone loach and minnows across a 4.7km stretch of the river. The full number of deaths, including fry, was estimated at 15,600.
They soon found the cause: digestate.
An umbilical pipeline split as it was being spread onto fields on 30 July 2019 by farmers A J Sing and Son Ltd. It was then washed off Pillavins Farm into a tributary of the river by heavy rain.
“This was a truly shocking fish kill, on a previously pristine salmon river. It was one of the largest fish kills ever recorded in Devon and Cornwall,” said EA officer Nicola Rumsey.
“The discharge of digestate into the river had a devastating effect on the fish population. It may take a number of years for the fish population to fully recover.
Speaking at Exeter Magistrates Court on Wednesday, Judge DJ Matthews quoted an Environment Agency fisheries enforcement officer who said “the fish kill was the worst he had seen in 30 years”.
The company pleaded guilty to causing an unpermitted discharge to water, contrary to regulations 12(1)(b) and 38(1) (a) of the Environmental Permitting (England and Wales) Regulations 201 6, and was fined £2,000, with £9,836 in costs. Ryan Adams, an employee at the time, admitted the same offence and was fined £667 with costs of £2,000.
The EA declined to discuss the magnitude of the fines. “Although we are responsible for putting cases together, it is for the courts to decide on the verdict/sentence and subsequent fines. It is our policy not to comment/express an opinion on these on or off the record,” said a spokesperson.
According to DEFRA records, the farm received almost £71,000 in subsidies in 2019, £27,000 of it related to ‘greening’ and agri-environment payments.
A J Sing and Son Ltd grows crops to provide feedstock for a nearby anaerobic digestion plant operated by Condate Biogas Ltd. The resulting digestate is then tankered back to the farm for temporary storage in a lagoon. To reach the fields where it was being spread by tractor, the digestate was pumped for more than a kilometre.
According to a statement made by the EA, “The court heard that A J Sing and Son Ltd were negligent in that they did not have systems in place to ensure that the proper checks had been made and to ensure that spills were properly dealt with; they used a method of delivery of digestate and equipment that introduced avoidable risks and used equipment that leaked.”
Adams, the firm’s sole employee, was also negligent in spreading digestate when rain was forecast, and in not cleaning up the spill.
Reflecting on the prosecution, Miles King, chief executive of People Need Nature, questioned why the biogas industry relied on a “Heath Robinson approach” to spreading digestate. “Aren't they just an ecological disaster waiting to happen? Some parliamentary questions need tabling,” he added.
“Great care must be taken when applying digestate to land. Simple observation of the weather forecast and the forecast of rain should have been enough to halt the digestate spreading,” said the EA’s Rumsey, noting that it should not be distributed on steep or waterlogged land, nor near ditches and watercourses.
A J Sing and Son Ltd could not be reached for comment.