Determination of DCGL for Site Closure of Nuclear Facility

To measure the degree of radioactive contamination of industrial facilities using depleted uranium as catalysts, and to release the site on this basis, RESRAD 6.21 was used to radiological impact assessment. Samples were taken from 20 points. Among the 20 sampling points, the highest point artificially contaminated (upper and lower part of point 16) was selected, and radiological impact was assessed and assessment and DCGL (Derived concentration guideline level) was computed. As a result, individual doses by nuclide were U-234: 4.162E-03 mSv/yr, U-235: 8.762E-04 mSv/yr, U-238: 2.204E-02 mSv/yr. In addition, the domestic dose standard relating to self-disposal and IAEA TECDOC-855 Clearance levels define the individual dose as 10 μSv. On this basis DCGL (Derived concentration guideline level) was computed, and it was 6.35E-02 Bq/g for U-238. (authors)