The toxic slick that has plagued the Songhua River since November 13 was expected to arrive overnight in Tongjiang, where it joins the Heilongjiang River on the border between China and Russia, according to sources from Heilongjiang Province Environment Protection Bureau.

China and Russia signed an agreement to cooperate in testing the water of the Heilongjiang River (called Amur in Russia), as the border runs along its middle, and six testing stations will be established along it, according to the bureau.

Yesterday, experts from both countries conducted three water tests at a station near Nizhneleninskoye, a port city in Russia's Jewish Autonomous Oblast.

They drilled holes in the ice on both sides of the river but no toxic chemicals had been found as yet, though they will be taking samples eight times a day from today.

The pollution was caused by a leak of 100 tons of benzene and other chemicals following a chemical plant blast along the upper reaches of the Songhua in Jilin Province on November 13.

The concentration of the slick has declined sharply since the spill, and is expected to be further diluted when it flows into the Heilongjiang River, Zhou Shengxian, director of the State Environment Protection Administration, said earlier this week.

Russian President Vladimir Putin said the incident "should not harm bilateral relations" after discussing it with Premier Wen Jiabao on the sidelines of the 1st Russia-ASEAN summit in Kuala Lumpur, Malaysia on Monday.

(China Daily December 16, 2005)