Leachate tests with sewage sludge contaminated by radioactive cesium.
The sewer systems of eastern Japan have transported radioactive fallout from the Fukushima Dai-ichi nuclear power plant accident to wastewater treatment plants, where the radioisotopes have accumulated. To better understand the potential problems associated with the disposal of contaminated sewage sludge in landfills, leachate tests were conducted with radioactive incinerator ash, cement solidification incinerator ash, and dewatered sludge cake. Radioactivity was undetectable in the eluate from incinerator ash and dewatered sludge cake, but about 30% of the radioactivity initially in cement solidification incinerator ash appeared in the eluate during the leaching experiments. Moreover, modification of test conditions revealed that the presence of Ca(2+) ions and strong alkali in the water that contacted the incinerator ash enhanced leaching of cesium. Lastly, the capacity of pit soil to absorb radioactive cesium was estimated to be at least 3.0 Bq/g (dry).
National Institute for Land and Infrastructure Management, Ministry of Land, Infrastructure, Transport and Tourism, Tsukuba, Ibaraki, Japan. tsushima-i92ta@nilim.go.jp
Ikuo
I
Tsushima
Masashi
M
Ogoshi
Ichiro
I
Harada
D002586:Cesium / Q000737:chemistry*; D002588:Cesium Radioisotopes / Q000737:chemistry; D060729:Coal Ash / Q000737:chemistry*; D004784:Environmental Monitoring; D006863:Hydrogen-Ion Concentration; D017745:Incineration; D007564:Japan; D011847:Radioactive Fallout / Q000032:analysis*; D012722:Sewage / Q000737:chemistry*; D012990:Soil Pollutants, Radioactive / Q000737:chemistry*; D013051:Spectrometry, Gamma; D013054:Spectrophotometry, Atomic; D013997:Time Factors; D064091:Waste Disposal Facilities; D014875:Water Pollutants, Radioactive / Q000737:chemistry*
D002588:Cesium Radioisotopes; D060729:Coal Ash; D011847:Radioactive Fallout; D012722:Sewage; D012990:Soil Pollutants, Radioactive; D014875:Water Pollutants, Radioactive; D002586:Cesium