Water quality tests in a section of China's Grand Canal on Saturday have shown no trace of contamination by a massive leak of concentrated sulfuric acid.
Local environment officials said an operation to neutralize the 200 tons of acid with about 900 tons of liquid alkali appeared to have been successful.
Test results from 15 monitoring stations near the leak site in Hangzhou, capital of Zhejiang Province, showed water quality had returned to "normal" by noon Saturday, said Shen Liyue, of the Environmental Protection Bureau of Yuhang District.
The results also indicated that the liquid alkali had caused no contamination in the waterway after reacting with the sulfuric acid to produce sodium sulfate, a kind of harmless salt.
The spill occurred early Thursday when a ship carrying 200 tons of concentrated sulfuric acid ran aground in the Yuhang section of the canal linking Beijing and Hangzhou, which was built in the 10th Century.
Traffic along the Yuhang section and the upper reaches was halted, but resumed late Thursday afternoon.
The ship, two thirds of which sank, was removed from the canal on Friday.
The total length of the canal is 1,794 kilometers. The navigable sections, mainly between Jining City, Shandong Province, and Zhejiang, stretch for about 1,000 kilometers.
(Xinhua News Agency August 6, 2006)