Road salt which leaked into a stream has cost a council a £10,000 fine.
Durham County Council was fined by magistrates at Darlington after its winter gritting store near Barnard Castle caused pollution to nearby Newsham Beck.
The council admitted an offence under the Environmental Permitting (England and Wales) Regulations 2010. The court heard that a local farmer reported in July 2012 that a number of newly-planted trees on a tributary of Newsham Beck had unexpectedly died.
Soil tests found that the ground contained 525 parts per million of sodium, some 17 times the amount found in soil taken from an unaffected area. There were also elevated levels of potassium.
Prosecuting for the Environment Agency, Louise Bogle told the court that investigations led officers upstream to the county council’s depot in Barford, Streatlam, where it was storing 7,500 tonnes of winter gritting salt. The salt pile had no cover on it, exposing it to rain, and there was a crack in the stone retaining wall, with liquid leaking through. An effluent storage tank – designed to catch any polluted water run-off – was found to be full and overflowing.
Water quality in the watercourse was affected for 2.5 km. Tests in August of that year showed that the water had a salinity of 13% – higher than the average salinity of sea water, which is 3.5%. Insects and aquatic plants in the beck had been severely affected.
The court was told the council had co-operated fully with the Environment Agency’s investigation and took remedial steps to cover the salt store, and removed contaminated soil from the drainage ditch.
The council, which was ordered to pay £2,882 costs, has since relocated the salt pile to Wolsingham, where it has built a new store at a cost of £500,000. After the case John Shelley, environment management team leader at the Environment Agency, said: “It is vital that organisations and companies do all that they can to ensure that their operations do not have a detrimental impact on the environment.”
John Reed, council head of technical services, said: “We already had plans to build new salt barns at Wolsingham and Hackworth and these plans were brought forward when the issues were highlighted. Open storage at Barford was not ideal.”
The Wolsingham salt barn cost £500,000 and work on the Hackworth barn, costing £1m, is scheduled to be completed by the summer.
Mr Reed said: “The investment is part of the council’s ongoing commitment to continue to provide the existing winter maintenance coverage of 45% of roads in the county which is higher than most areas in the UK. This area of our work has also been highlighted as a priority by our residents.”