The incident in April 2002 wiped out all fish and invertebrate life in a 17-kilometre stretch of the Tarty Burn, an important tributary of the Ythan, a major trout river, and also killed some marine life in a nature reserve in the estuary. The estimated fish kill ran to 74,000 for sea and brown trout alone.
The incident was caused by a crack in a concrete tank at a pig farm near the village of Udny operated by Arthur Simmers. Investigations by the Scottish Environment Protection Agency revealed that the tank, which had capacity for some 4.5 million litres of pig slurry, was around three-quarters full at the time.
A SEPA officer told Aberdeen sheriff court how, on arriving at the farm, he had seen a 30-foot wide river of slurry flowing from the tank towards the watercourse. The Agency believes that this was the largest ever slurry spill in Scotland.
A SEPA spokesman commented: "The means of construction and maintenance of the slurry storage tank made a significant contribution to the cause of the failure of the tank. Had the tank met the accepted standards it is likely this environmental disaster could have been avoided."
The £10,000 fine for causing or knowingly permitting polluting matter to enter controlled waters brought to an end an eventful 12 months for Mr Simmers.
His company, Scotpigs, was once the second largest pig enterprise in Scotland, and he himself had been chairman of the Scottish Pig Association.
However, in December 2003 the company was expelled from the industry’s Quality Meat Assurance scheme after animal welfare campaigners secretly filmed pigs being reared in squalid conditions at four of its farms. And last March, Scotpigs was wound up by court order following feuding between Mr Simmers and a co-director over the firm’s debts of over £2 million.