Preliminary Assessment of Radiometric Survey over a Dumpsite in eket Urban, South-Eastern

Abstract

A radiometric survey was conducted at a dumpsite in Eket Urban, south-eastern Nigeria, with the aim of monitoring low of radioactive contamination . The dumpsite is located behind the defunct Qua Steel Complex in Eket Urban, Akwa Ibom State, Nigeria. The Study area is located between latitude 04° 37′ 07.7″ and 04° 37′ 00.4″N and longitudes 007° 56′ 11.4″ and 007° 56′ 23.5°E, in Benin Formation. The dump contains mixed waste of different materials like kitchen and other household wastes, industrial, agricultural wastes, etc. A portable radiation survey scanner REED R8008 was used to quantify the exposure levels in the dump.Gamma radiation exposure rates in counts per minute (cpm) were obtained from two profiles which were oriented at N 80° E and N 90° W of the dump at increasing distance of 5m from the reference points. A plot of exposure rate in counts per minute versus distance reveals that Profile 1 has almost uniform amplitude with a range of 29 to 37 cpm, the highest amplitude recorded at an interval of 90m Profile 2 shows higher amplitudes of gamma ray levels ranging from 3.2 to 42.6 cpm, with the relatively higher amplitudes of 40.1 to 42.6 cpm within the dumpsite. A gradual drop towards the adjoining farmland was noticed. The results therefore reveal higher gamma radiation in the dumpsite compared to gamma radiation of 3.2, 3.8, and 3.2 cpm respectively at the three control points. The gamma radiation emission levels from the dump in the range of 20.4 to 42.6 cpm (0.12 to 0.24 Sv/hr) could be accumulated and become hazardous if not properly managed, to forestall the exceeding of 1mSv/year set by the International Commission on Radiological Protection (ICRP) for the environment and general population.