Sulphur dioxide emissions from India's top copper smelter were within limits during an inspection by a court panel, according to a report seen by Reuters, which could help lead to a ruling in favour of reopening the plant.
The Sterlite Industries' plant, which produces 30,000 tonnes of refined copper a month - or more than half of India's total production, was shut on March 30 after complaints about emissions. The shutdown is squeezing local supplies of refined copper and boosting prices in India.
National Green Tribunal, a fast-track court hearing the case, had set up an expert committee to measure emissions and examine the working condition of machinery, among other things.
"The emissions from all the stacks were well within the permissible limit prescribed by the Central Pollution Control Board when the plant was in normal operation," said the report by P.S.T. Sai and Ligy Philip.
"In addition to this, the ambient SO2 concentrations in all the 16 monitoring stations were within the permissible limit, when the plant was in normal operation."
In a hearing on Wednesday, Justice Swatanter Kumar of the tribunal said that the expert panel's report had to be given to all parties before the next hearing on May 14.
The closure of the smelter, which uses imported concentrates, has pushed about 3,000 tonnes per day of concentrates onto the market. Cashing in on regional oversupply after the closure, smelters across Asia have been charging the highest fees in five months to process concentrates.
Sterlite is a unit of London-listed resources conglomerate Vedanta Resources Plc, which is controlled by billionaire Anil Agarwal.