The radioactive fallout @entity5166 ((137)Cs) in the sewage sludge ashes (SSAs) produced in Japan after the Fukushima Daiichi Nuclear Accident was tested. Five samples of SSAs produced in 2011 and 2012 were tested. Two of the samples contained (137)Cs (23 and 9.6  kBq/kg, respectively) above the radioactivity criterion (8  kBq of radioactive Cs/kg of solid) for controlled landfill disposal in Japan. The mineral components of SSA are roughly divided into two groups: an @entity5828 -soluble phase mainly composed of @entity6546 and @entity28600 ; and @entity7182 , including quartz, feldspar, and clay. Both phases contained (137)Cs. The majority (up to 90%) of (137)Cs was contained in the @entity5828 -soluble phase. Among the @entity5828 -soluble subphases, Fe-bearing phases that were probably iron oxides were mainly responsible for (137)Cs retention. No positive evidence was obtained that showed that @entity1391 -bearing phases, which were included most in SSAs along with the silicate phase, retained (137)Cs. Pre-pulverizing SSAs and heating them at 95    C in a 6  M or a concentrated aqueous @entity5828 was the most effective method of dissolving the @entity5828 -soluble phase. The radioactivity concentrations of (137)Cs in all the @entity5828 -treatment residues were below the radioactivity criterion. This residue was mostly composed of @entity7182 . After static leaching tests of the residue at 60    C for 28 days, no (137)Cs was detected in simulated environmental water leachates (pure water and synthetic seawater), demonstrating that (137)Cs in the residue is very stably immobilized in the @entity7182 .

Radioactive fallout XXXX in sewage sludge ash produced after the Fukushima Daiichi nuclear accident.

@entity7182 :: ('MESH:D017640', 'Chemical') :: ['silicates'] @entity6546 :: ('MESH:D010710', 'Chemical') :: ['phosphates'] @entity5166 :: ('MESH:D002586', 'Chemical') :: ['cesium'] @entity1391 :: ('CHEBI:26020', 'Chemical') :: ['phosphate'] @entity5828 :: ('CHEBI:17883', 'Chemical') :: ['HCl'] @entity28600 :: ('MESH:D010087', 'Chemical') :: ['oxides']
@entity5166 :: (MESH:D002586,Chemical) :: ['cesium']
