View of a POSCO steelworks in Gwangyang, about 390 km (242 miles) south of Seoul, is seen in this March 16, 2007 file photo. Pohang's oldest furnace, with a 35-year history, helped POSCO grow into the world's No.4 steel giant. But it may soon become a thing of the past as POSCO, which alone produces around 10 percent of South Korea's total carbon dioxide, moves to new technology to cope with stricter carbon emission rules. To match feature ENVIRONMENT-SUMMIT/KOREA-CARBON REUTERS/Lee Jae-Won/Files (SOUTH KOREA)