Radiometrical and physico-chemical characterisation of contaminated glass waste from a glass dump in Sweden

Abstract

Around former glass factories in south eastern Sweden, there are dozens of dumps whose radioactivity and physico-chemical properties were not investigated previously. Thus, radiometric and physico-chemical characteristics of waste at Madesjö glass dump were studied to evaluate pre-recycling storage requirements and potential radiological and environmental risks. The material was sieved, hand-sorted, leached and scanned with X-Ray Fluorescence (XRF). External dose rates and activity concentrations of Naturally Occurring Radioactive Materials from 238U, 232Th series and 40K were also measured coupled with a radiological risk assessment. Results showed that the waste was 95% glass and dominated by fine fractions (<11.3 mm) at 43.6%. The fine fraction had pH 7.8, 2.6% moisture content, 123 mg kg−1 Total Dissolved Solids, 37.2 mg kg−1 Dissolved Organic Carbon and 10.5 mg kg−1 fluorides. Compared with Swedish EPA guidelines, the elements As, Cd, Pb and Zn were in hazardous concentrations while Pb leached more than the limits for inert and non-hazardous wastes. With 40K activity concentration up to 3000 Bq kg−1, enhanced external dose rates of 40K were established (0.20 μSv h−1) although no radiological risk was found since both External Hazard Index (Hex) and Gamma Index (Iγ) were <1. The glass dump needs remediation and storage of the waste materials under a safe hazardous waste class ‘Bank Account’ storage cell as a secondary resource for potential future recycling.