Over the past months, ILVA and the Italian government have been trying to keep the plant in operation while remediation measures necessary for ILVA to obtain environmental authorization (AIA) were being carried out.
The case had sparked a national debate over whether the site, located in a region of the recession-hit country where unemployment exceeds 30 percent, should be shut down threatening the jobs of some 12,000 workers.
The probe was opened after a local study demonstrated that the area surrounding the plant suffered from a mortality excess up to 15 percent, due to fumes and dust particles causing cancer and other diseases.
Local analysts estimated the plant stop would trigger a drop by about 5 percent of the southern region's output, with a consequent short-term supply squeeze that would ripple out to prices in southern Europe and nearby regions.
ILVA, founded in 1905 and since 1933 a state-owned site, was bought in 1995 by privately-held group Riva. In 2011 the company produced 8.5 million tons of steel, almost a third of the Italian total steel production.
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