Measurement of radioactivity concentration in soil samples around phosphate rock storage facility in Richards Bay, South Africa

Abstract

Mining, mineral processing and industrial activities have long been linked to increased levels of radioanuclides in soil in their vicinity. In this work, concentrations of naturally occurring radionuclides in soil samples collected around a rock phosphate storage facility in Richards Bay in South Africa were determined. A total of 90 soil samples were collected and analyzed for 238 U and 232 Th using neutron activation analysis and 226 Ra and 4 K using a HPGe detector. The results revealed the average radioactivity concentrations of 238 U, 232 Th, 226 Ra and 4 K in soil samples collected around the rock phosphate storage area

Determination of uranium and thorium concentration and gross alpha and beta activity measurement in top soil samples from Richards Bay, South Africa

“…These usually lead to the spread of NORMs contaminating the environment and subsequently results in potential radiation exposure of workers and member of the general public. Although research has reported the radionuclide content of the rock phosphate stored in this study area (Masok et al, 2016a) and the quality of water within Richards Bay (Lin, Biyela, Puckree, & Bezuidenhout, 2004;Masok, Masiteng, Mavunda, Maleka, 2017a;Masok, Masiteng, Mavunda, Maleka, Winkler, 2017b;Vetrimurugan, Brindha, & Elango, 2017), no available literature is published about the concentration of radionuclides in soil within the precinct of this rock phosphate storage facility. This study is intended at bringing to light the concentration of parent radionuclides in soil around the rock phosphates storage facility at Richards Bay with an aim to map out hot spots in term of radioactivity concentration level.…”

“…A total of ninety soil samples were collected from 30 sampling positions spread across the coal area (Area 1), the rock phosphate storage area (Area 2) and undisturbed area called the control area (Area 3). The location of all sampling positions are fully shown on the map of the study area in our previous publication (Masok et al, 2017b).…”

“…In the laboratory, soil samples were each transferred into a separate metal drying pan and dried at a temperature of 105 C for 24 h in an oven (Labotech; model number MT 202) to remove all residual moisture and to obtain samples with constant weight. The dried samples were pulverize into fine power for homogeneity (Masok et al 2017b). Pulverized homogenized samples were each transferred into a separate 500 ml wide mouth plastic containers to allow for sub-sampling for gross alpha and beta activity measurement and gamma spectroscopy.…”

“…Following the spectrum analysis, specific activity (activity per unit mass) of 238 U and 232 Th were determine in units of Bq$kg À1 using a methodology fully described our earlier publication (Masok et al, 2017b). The results obtain were then converted into the fraction of the elemental within a sample ðF E Þ in unit of part per million (ppm) equivalent to mg.g À1 of 238 U; 232 Th and 40 K using…”

X-ray diffraction and gamma-ray analysis of rock samples from Haradh Region in Saudi Arabia

“…Several studies have been made in many countries to determine the concentration of the natural radionuclides in rock samples, e.g. Masok, Masiteng, Mavunda, Maleka, and Winkler (2018), Prakash, Kaliprasad, and Narayana (2017), and Uosif, Hashim, Issa, Tamam, and Zakaly (2016). The objectives of the present study were to determine metal composition and measure the natural radioactivity levels of 226 Ra, 232 Th, and 40 K in rock samples collected from an important site in Saudi Arabia (Haradh region) also to assess the radiological hazard indices in the air and to compare the results with international levels.…”