Photo taken on June 7, 2011 shows the biotoxicity monitoring pool at Jiuxi Waterworks in Hangzhou, capital of east China's Zhejiang Province. The water sources for five water utility companies that were shut down in wake of a chemical spill in Xin'an River are safe again, the provincial environmental protection bureau said Monday. Earlier the chemical spill affected water supplies for at least 552,200 people in Fuyang and Tonglu, two county-level regions in suburban Hangzhou. The bureau also ordered close monitoring of water quality that could prompt shut-down of water plants again in case pollution increased at their water-taking points. [Xinhua/Huang Zongzhi]