According to local people, fish began dying on the night of December 7. Local people rowed boats to collect dead fish. They sold big fish to the market and used the small fish as cattle feed.
“Hemibagrus of 2-3 kg agonized on the water surface and died. We could use bare hand to catch them, which are usually very strong. Not only hemibagrus, other fish also died en masse on the river,” said a local man – Bui Van Quyet.
According to locals, this phenomenon did not happen before. “On the morning of December 8, the villagers went to the river and saw dead fish floating on the river. We called each other to use boats to collect fish. Some people picked up hundreds of kilos of fish a day,” Quyet added.
Locals said that before the fish died, the water on the Buoi River suddenly changed into dark color, with an unpleasant odor.
Mr. Le Huy Duong, Chair of Thach Lam commune, said: “It is very strange that fish of up to 3-4 kg also died. Local people collected several tons of dead fish.”
Duong said he had reported the phenomenon to the district government and some environment police officers came to collect water for testing.
Currently, there are still a lot of dead fish floating on the water. Along the riverbank, the smell is very terrible.
Mr. Tran Xuan Hai, technical manager of the cassava plant, said that waste water is processed in an 80,000cu.m biogas tank and the plant only discharges about 1,000cu.m of treated waste water to the river.
This plant has four wastewater reservoirs. The water here is always dark and smells. There is a flow of water from the plant to a reservoir and to the Buoi River. Hai explained that this is the water to wash cassava so it does not affect the environment.
Mr. Nguyen Quang Thai, Director of the Thanh Hoa Provincial Environmental Protection Division said that all production facilities in the upstream area of the Buoi River would be inspected.
“We will strictly punish the polluting facility but currently we are investigating because there are several pulp plants in the upstream area,” Thai said, adding that this is the first time fish dying en masse in the Buoi River.
In related news, three toothpick, chopstick and pulp plants discharging untreated waste water to the Ma River, in Quan Hoa district, Thanh Hoa province have been temporarily closed.