The chief of a tap water supplier embroiled in scandal after a contamination affected more than 2.4 million people in a northwestern Chinese city apologized to the public on Tuesday. Yao Xin, chairman of the Lanzhou Veolia Water Company, bowed and expressed his apology at a news conference organized by the government of Lanzhou City, capital of Gansu Province, after the company reported excessive levels of carcinogenic compound benzene in its water on April 10. Yao said the reason he had not apologized since then was that he and all his staff had been putting all their energy into identifying the cause of the contamination and building new water pipelines. He said the company will launch a website in the first half of this year, and disclose water quality results on a monthly basis on the site. On April 11, the city government warned residents not to drink tap water for 24 hours, after more than 10 times the national standard of benzene was found in the tap water. The pollutants are believed to have leaked from a pipeline of Lanzhou Petrochemical, a subsidiary of China National Petroleum Corporation, the country's largest oil company.