It was a high B.O.D. (biological oxygen demand)
sewage discharge from Severn Trent Water's Strongford works at Barlaston that caused the fish kill IMO. Not Cyanide, well not directly as reported in the media, which can occur in nature and at much higher concentrations (try marzipan to learn the taste).
http://www.guardian.co.uk/uk/2009/oct/07/pollution-river-trent-investigation
...the fish kill had affected 20 miles of the river. Anglers had first spotted fish gasping for air "like canaries in a mine" on Monday, he said.
The levels of cyanide were less than one part per million but "aquatic life is very sensitive to poison," he said.
The cyanide had killed the bacteria used at the treatment works, and a combination of ammonia, from the sewage, and cyanide had killed the fish.
They would all have killed the anaerobic bacteria in the deep 'activated' sludge that treats the sewage.
Anything more than 50 ppm should not have been discharged.
Therefore entirely preventable with proper monitoring; however carelessnes (
or worse ) seems to have set in there. In my mind; it's inconcievable they didn't know this.
NB. The exact same works was fined only last month for another pollution incident earlier this year - not that AT (Fish Legal) or ACA involved themselves.
http://www.thisisstaffordshire.co.u...ver-Trent/article-1357150-detail/article.html
SEVERN Trent Water has been ordered to pay almost £10,000 for polluting the River Trent.
It admitted causing sewage pollution to enter the river.
Stafford Magistrates Court was told Strongford Sewage Treatment Works, Barlaston, has an average of 150 million litres of water flow through it each day, with the final, treated water pumped into the Trent.
Amy Jacobs, for the Environment Agency (EA), said it treats sewage and trade effluent from across the area.
But on January 12, the EA noticed the effluent coming from the plant was brown and had a sulphurous smell.
Severn Trent took immediate action, stopping overflows on the afternoon of the incident.
The firm was fined £6,700 and ordered to pay £2,777 costs and a £15 victim surcharge.
A Severn Trent spokesman said the utility "deeply regrets" the incident.
He said: "This incident followed an unfortunate and unusual series of events, where sludge deposits were dislodged during an operation to reduce ammonia levels in the effluent. "We have introduced processes to reduce the risk of pollution in future, and are spending £46 million upgrading the plant."
How convenient to set the public on the waste disposal company. And to name them, usually they aren't for
'legal reasons'. It certainly took the heat off management of the Strongford Sewage Works, who, yet again, through various failings, allowed noxious effluent to destroy that part of the river.
There is much baying on this thread for a custodial sentence. I would prefer to see whoever physically let this stuff into the Trent, and the senior manager in charge, both receive a custodial sentence, not suspended, for this criminal negligence.
