Two men work on an ice sculpture at a park in Harbin, northeast China's Heilongjiang Province, as the provincial capital prepares for its annual ice and snow festival in January. The city government says its water supply for the ice is safe after a factory blast in Jilin Province polluted the Songhua River. According to the latest environmental monitoring report, the density of nitrobenzene, the major toxic compound in the polluted river, has dropped within the state's safety standard.