Shynar Jetpissova, Communications Associate in the World Bank Office in Kazakhstan, offers this story.
Mercury pollution is invisible but dangerous. For decades, a factory just 2 km from Temirtau threatened the health of the 170,000 people living there, and their fragile environment.
The hazardous legacy leached from a former carbide factory that operated for almost fifty years, producing synthetic rubber from 1950 to 1997 with mercury as a catalyst. The factory’s wastewater treatment plant was not designed to remove mercury. As a result, more than 1,500 tons of this heavy metal were discharged into the Nura River.
A project supported by the World Bank and the Government of Kazakhstan invested into the cleanup of the contaminated area to reduce health risks from this toxic substance. The 60 hectare industrial site and an 18 kilometer stretch of the Nura’s riverbanks and flood plains—totaling more than 3,500 hectares—are now cleaner and safer.
Yuri Kornev worked as a project engineer at the factory for 25 years. He says: "During the production process there were 30-50% losses of pure mercury. People working in the factory knew about the danger, as they passed instructions. But those living in the surrounding areas were unaware. The staff passed medical examination twice a year, and in case of a disease they were transferred to another job."
About 170,000 samples taken unveiled a terrifying picture—the level of mercury contamination at the industrial site was in some areas 150 times higher than international standards allow.
Manfred Nussbaumer, Chief Project Engineer says, "Once we got a full picture we were able to evaluate the danger and effect for the people living around and down the stream of the Nura River through Intumak reservoir, because Nura is a very popular place for fishing and resting."
Between 2008-2009, the carbide factory was completely and safely demolished and transported to a specially designed and built hazardous waste landfill. Polluted soil was excavated to a depth of two meters and transported to the landfill. Also, all the metallic mercury left in the factory was collected and immobilized in concrete as well as plastic containers.
Sludge from the wastewater treatment plant beds contained mercury, too, and was cleaned up, as were the Zhaur Swamp and the old ash lagoons of the thermal power plant. Overall, based on pollution sampling and mapping, more than 2,000,000 tons of contaminated materials from the carbide factory, the sedimentation ponds, swamp, river banks, and floodplains were safely disposed. The giant landfill containing them was covered with a layer of top soil to create a green cover.
According to the World Health Organization, mercury seriously affects kidneys, the liver, gums, and the central nervous system.
Since 2007, the Kazakhstan Hydrometeorological Center has been keeping a close eye on the Nura River basin. "Environmental monitoring includes sampling and chemical analysis of the water, sediments, and soil for various indicators," says Victoria Hildebrandt, Head of Integrated Laboratory of the Karaganda Center of Hydrometeorology. "Special emphasis is given to the monitoring of mercury pollution. To estimate the treatment results continuous monitoring is required, but in the long term the benefits of the cleanup works are obvious."
To restore and strengthen water flow management the project rehabilitated the Intumak Reservoir.
"Construction of this controlled spillway has two aims: environmental and economic, since only clean water will go down the river now, and the volume of irrigated lands can now be increased," says Baldabek Zhusupbekov, Posh+Partners Consulting Engineer. "With the flood spillway of 11 gates and capacity of max 3000 m/sec, the reservoir volume will be increased by 100 mln m3."
In addition, a new two lane bridge is connecting two settlements, and shortening the travel distance between them from 80 km to 15.
Seasonal floods severely hit several villages along the Nura River every year. With the construction of village protection dams, and river banks diverted and reinforced, the spring floods will not reach the houses anymore.
Toijan Mongolkhan a villager from Sadovoye said their house flooded every spring. "The river was very close, just 5 m from the house. Our gardens, houses, and crops remained under water every season. The year before last, severely hit families were evacuated to a nearby village. It’s good that the river was drawn aside, because our children used to play right here."
Thanks to better water management, the Korgalzhyn wetlands, a UNESCO World Heritage site and habitat for one of the world’s largest nesting populations of flamingos, and other endangered species will benefit from controlled water flows down the Nura River.
"The Nura River cleanup project aimed at improving the welfare and health of the population living near the Nura River," says Ondasyn Zhienkulov, Deputy Chairman of the Committee of Water Resources, Ministry of Agriculture of the Republic of Kazakhstan. "All the components are successfully implemented. Under the third one - the construction of the Intumak dam - the works are well underway, and we expect to launch the facility in the first half of 2012."
All clean-up measures undertaken at Nura River basin mean that the people unaware of invisible threat and the environment are now safe from mercury.