The environmental protection bureau of northeast China's Heilongjiang Province said yesterday that subfreezing temperatures are slowing the progress of the chemical slick down the Songhua River and that the density of pollutants, chiefly nitrobenzene, remains high.
   
In a news release the bureau said the river is now frozen over in parts and, as of Thursday afternoon, the 150-kilometer stretch of pollution was lingering near Tonghe County.
   
The main body of pollution was detected close to Mulan monitoring post at 4 AM yesterday with a nitrobenzene density 27.47 times above the national limit.
   
Meanwhile, Tonghe monitoring post further downriver reported a nitrobenzene density of 0.1548 milligrams as of 8 AM the same day, 8.11 times the limit, and was growing.
   
The stretch is expected to reach Dalianhe Township of Yilan County at 2 AM tomorrow and arrive at Jiamusi, the province's second largest city, on December 6.
   
Yilan's local government has shut down water collection channels from the river and is controlling essential use by large enterprises.
   
The county government has asked all Dalianhe residents to store water for five to seven days for when their supply is cut off as the pollution belt passes by.
   
It has also taken emergency measures to ensure a daily 3,500-ton supply to the township, where more than two thirds of residents use river sources for drinking water.
   
Li Yizhong, head of the National Bureau of Production Safety Supervision Administration, arrived in Jiamusi yesterday to examine the city's prevention and preparation work.
   
He affirmed the achievements cities on the river have made during the past days, but said it was "merely a temporary triumph over the pollution."
   
Li said the government must clearly see that the situation is still very serious for cities on the lower reaches of the river with an expanding pollution belt and still-high pollutant densities.
   
The pollution was caused by a chemical plant blast on November 13 in neighboring Jilin Province, resulting in massive leak of toxins into the Songhua River.
   
Harbin, capital of Heilongjiang with the river as its main water source, resumed peak supply of water on Sunday after a five-day suspension.
   
(Xinhua News Agency December 2, 2005)