Sheffield firm Firth Rixson Metals Ltd has been ordered to pay a fine of £80,000 after pleading guilty to polluting a watercourse in Glossop.

The Environment Agency prosecuted the company after over 600 litres of a solution of hydrochloric acid, caustic soda and water polluted nearby Shelf Brook.

This had a significant impact to the brook, resulting in 199 dead brown trout within a 500 metre stretch, with invertebrates also affected over two kilometres. The fins and eyes of the fish were noted to have a burnt appearance.

A member of the public initially reported the pollution in Shelf Brook to the Agency’s Incident Hotline in April 2015.

Officers attended the area and found dead fish. Samples taken from the brook and a drain leading from the Firth Rixson Metals site into the brook were found to contain a highly alkaline liquid, made up of various metals, at elevated levels.

As part of Firth Rixson Metal’s manufacturing process, an acid scrubber was used. Hydrochloric acid emissions were neutralised with caustic soda. Below the scrubber was a waste tank in a plastic containment bund.

The Environment Agency investigation identified a valve had been left open which allowed water into the scrubber unit and the automatic dosing equipment had continued to add caustic soda. 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 entered the nearby drain to the brook. The company had failed to cap the drain, despite recent advice from local authority inspectors.

Pollution had significant impact

In sentencing, District Judge Davison said Firth Rixson Metals Ltd had allowed a state of affairs to exist which led to the incident.

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. The sentencing sends out a very clear message to anyone whose recklessness and negligence causes serious pollution to the environment. We will not hesitate to take action against polluters.”

Firth Rixson Metals Ltd pleaded guilty to causing a water discharge activity contrary to the Environmental Permitting (England and Wales) Regulations 2010.