A company has been fined £80,000 after pleading guilty to polluting a High Peak watercourse.
The Environment Agency prosecuted Firth Rixson Metals Limited after over 600 litres of a solution of hydrochloric acid, caustic soda and water polluted Shelf Brook in Glossop in April 2015.
Speaking after the court hearing, Mark Easedale, Environment Manager for Greater Manchester, said: “This pollution incident had a significant impact on Shelf Brook, killing brown trout, which are a key indicator species of good water quality."
In total, 199 brown trout were killed within a 500-metre stretch of the brook, with invertebrates also affected over a distance of two kilometres. The fins and eyes of the fish were noted to have a burnt appearance.
Samples taken from the brook and from a drain leading from the Firth Rixson Metals site to the brook were found to contain a highly alkaline liquid containing a variety of metals at elevated levels.
As part of Firth Rixson Metal’s manufacturing process an acid scrubber is used whereby hydrochloric acid emissions are neutralised by being dosed with caustic soda. Below the scrubber was a waste tank sat within a plastic containment bund.
An investigation by the Environment Agency identified a valve had been left open allowing water into the scrubber unit and the automatic dosing equipment had continued to dose this with caustic soda.
It said staff failed to respond properly to alarms and a pump which should have returned the solution failed to activate. This resulted in a highly alkaline solution overflowing from the containment bund which then entered the nearby drain leading to the brook.
The company had failed to cap the drain despite recent advice from a local authority inspector, the agency said.
Firth Rixson Metals pleaded guilty to causing a water discharge activity not under and to the extent authorised by an Environmental Permit contrary to the Environmental Permitting (England and Wales) Regulations 2010. In addition to a fine, the company was ordered to pay costs of £18,952.35 and a victim surcharge of £120.
District Judge Davison said Firth Rixson Metals Ltd had allowed a state of affairs to exist which led to the incident.
Mr Easedale added: "The sentencing sends out a very clear message to anyone whose negligence causes serious pollution to the environment.
"We will not hesitate to take action against polluters."
In mitigation the District Judge recognised the actions the company had taken since the incident to prevent a recurrence.