Citing a possible ecological disaster and the foul smell from the capital’s main sewage treatment plant, the Piraeus Prefecture yesterday ordered the unit to be shut down. The authority said it was fining the Athens Water Company (EYDAP) 55,201 euros and revoking the license for the troubled Psyttaleia plant, on an islet between Piraeus and the island of Salamis. This followed persistent complaints from Piraeus residents about the stink caused by the plant and fears that the buildup of sewage would lead to the pollution of surrounding waters, Piraeus Prefect Yiannis Michos said. Some 150,000 tons of sludge have built up at the plant, and despite efforts to disinfect the waste with lime, Michos said there was a danger of polluting the Saronic Gulf and people being infected. Until last March, 300 tons of sludge had been transported daily from Psyttaleia to the Ano Liosia dump 21 kilometers away. But this was stopped when the waste caused landslides. A new unit to dry and compress the sludge has still to be built. In July, the EU said it would sue Greece on the matter.