Environmental radiation and health risk assessment in the neighborhood of a radioactive waste management facility.

The Radioactive Waste Management Center (RWMC) of the Ghana Atomic Energy Commission (GAEC) operates a licensed radioactive waste management facility known as the Centralized Radioactive Waste Management Facility (CRWMF). The Center undertakes environmental radiation monitoring in which indoor dose rates at various microenvironments, and nearby ambient environments of the facility are measured. A 2-year radiation dose data (i.e., 2017 and 2018) obtained from the monitoring exercise was used to determine whole-body exposure and cancer risk analysis for adult and child age groups. With the exception of the high dose area of the facility, observed doses in all microenvironments of the facility as well as the ambient environment were below the regulatory dose limits of 1 mSv/y and 20 mSv/y, set for radiation workers and the general public, respectively. Dose rate variation for the 2017 and 2018 datasets were not significant (p > 0.05) at 95% confidence interval (CI). Cancer risks due to exposure to alpha, neutron, and gamma radiation sources for both adult and child age groups were above the global average value of 2.90 × 10-4 reported by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Gamma sources recorded the highest cancer risk followed by neutron and alpha sources with risk values of 3.95 × 10-1 and 3.92 × 10-2; 4.06 × 10-2 and 4.03 × 10-3; and 7.96 × 10-4 and 7.91 × 10-5 for the adult and child age groups, respectively. Radium (226Ra) recorded the highest activity concentration (9.62 × 1010 Bq) with 4 quantities in the inventory while plutonium-beryllium (as alloyed source) recorded the lowest activity concentration (9.82 × 1001) with 12 quantities in the inventory.

Rainfall erosivity index for the Ghana Atomic Energy Commission site.

Rainfall erosivity is the potential ability for rainfall to cause soil loss. The purpose of this study was to estimate the rainfall erosivity index for the Ghana Atomic Energy Commission site in order to compute the surface erosion rate. Monthly rainfall data, for the period 2003-2012 were used to compute annual rainfall erosivity indices for the site, using the Modified Fournier index. Values of the annual rainfall erosivity indices ranged from 73.5 mm for 2004 to 200.4 mm for the year 2003 with a mean annual erosivity index of 129.8 mm for the period. The Pearson's Coefficient of Correlation was used to establish the relationship between annual rainfall and annual rainfall erosivity. This showed a high degree of positive relationship (r = 0.7) for the study area. The computed mean annual erosivity index revealed that the site is in the high erosion risk zone. Therefore, it is necessary to develop soil protection and management strategies to protect the soil from erosion.