Radioactivity Risk of Dump-Site Exposure to Students at Daniel Hall in Covenant University

A radiometric assessment of the activity concentrations of 238U, 235Th and 40K was conducted in Covenant University dump site located about 200-400 meters behind Daniel hall. For this study the RS-125 Super Spec hand held radiation detector was used alongside a GPS to take down location coordinates. Fifteen stations were measured, in the dump site, some meters away from the dumpsite, by the sides and in front of Daniel hall. The activity concentration of radionuclides varies from 11.42 ± 0.3 to 44.76 ± 0.2 Bqkg-1 with a mean value of 27.31 Bqkg-1 for 238U, 33.29 ± 0.8 to 213.96 ± 0.4 Bqkg-1 with a mean value of 69.14 Bqkg-1 for 252Th and 31.3 ± 0.2 to 1017.25 ± 0.6 Bqkg-1 with a mean value of 275.96 Bqkg-1for 40K. The absorbed gamma dose rates exposed to students around the area varies from 81.56 to 442.31 ± 2.2 nGry-1 with a mean value of 152.25 ± 2.2 nGry-1.The annual outdoor and indoor effective dose equivalent was 0.18 mSv and 0.274 mSv respectively. Comparing the radiological health risks from the present study with the average world standard by ICRP (International Commission on Radiological Protection) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR,2000) recommended standard values of 1 mSv, it is within the range. This study revealed that the risk exposure to the students at Daniel Hall may not be from the dump-site, rather, the granitic crushed rocks used for constructions near Daniel Hall may be the risk implication