IMERYS Minerals has been ordered to pay £3,168 in fines and costs after liquid china clay escaped into the River Fal. The case was brought by the Environment Agency.

The Environment Agency was alerted by a member of the public on January 30, 2004 after they saw the Fal at Tregony was heavily discoloured. Imerys later contacted the Environment Agency and confirmed that liquid china clay had polluted the river following a pipe burst at Trethosa. Later the same day another member of the public reported the River Fal was polluted at Grampound upstream from Tregony.

The clay leak was traced to a surface water ditch that had been blocked off with sandbags to prevent further spillage from a fractured clay line. A formal sample was taken from the Fal at Trenoweth, some four kilometres downstream of Trethosa.

Following the incident Environment Agency officers monitored the River Fal to assess the impact of china clay on the river. An investigation of Trethosa Moor led to the discovery of a second burst pipeline. An officer also found evidence of a third clay spillage by a pumping station, contained on the surface of the ground.

"It is important clay companies carry out regular checks of ditches and watercourses when clay is being transported by pipeline. If china clay escapes into watercourses, the fine particles can seriously damage the river ecology, smothering the riverbed and killing off freshwater creatures and fish eggs," said Phil Christie for the Environment Agency.

The upper and lower reaches of the River Fal including Carrick Roads have been designated for their importance as Special Areas of Conservation and Sites of Special Scientific Interest.