(ANSA) - Rome, August 7 - A court on Tuesday upheld a decision to impound and overhaul portions of the ILVA steelworks in Taranto and to hold its former presidents and ex-director under house arrest after evidence of long-standing toxic pollution was found last month. "The guardians must ensure the safety of the facilities and use them according to the completion of all necessary technical measures to eliminate hazards, and they must implement an emissions-monitoring system," said the ruling. The court also decided that former presidents Nicola and Emilio Riva, who is currently the plant owner, and ex-director Luigi Capogrosso must remain under house arrest, while five other suspects were released. The court named current ILVA President Bruno Ferrante the administrator to oversee the impounded portions of the plant. A court in July ordered the company to halt its mineral park and foundry zones that prosecutors say have poisoned nearby areas since 1995, a decision that threatens the future of Europe's largest steel plant. The company has appealed against the court order and the appeals process is due to begin in earnest after September 15. Last Friday the government approved the allocation of 336 million euros for environmental remediation and recovery at the plant with immediate effect in an effort to keep the steelworks in production while protecting the health of local people. On Monday the ILVA president said that shutting down the steelworks in Taranto could lead to closures at plants in Genoa and Novi Ligure, which "survive on the what is produced in Taranto". Earlier Tuesday Industry Minister Corrado Passera said that closing the plant must "be avoided". "If it's closed, it will not reopen," he said, then struck back at closure threats across the country, calling the dilemma of accepting toxic working conditions in exchange for industrial output "unacceptable".