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In many developing countries, the scarcity of potable water is an ongoing challenge. Even when water is plentiful, its quality may be unsuitable for household use such as in the city of Kinshasa in the Democratic Republic of Congo (DRC) which is the study area for this investigation. Shortage of potable water has forced inhabitants in the city to rely on water wells dug without adherence to regulations or specifications within perimeters of their homesteads. The water from such wells is often polluted with household waste being generally disposed by burning and burying in shallow pits, thrown in pit toilets or into rivers. Such practices have led to contamination of ground water. This study examines the water quality of drinking water drawn from wells in Fer-bois, which falls under the Kimbanseke municipality in the South East of Kinshasa. The dynamics of well design/location, sources of possible contamination with respect to water treatment and water quality as well as its possible impact on health are examined. The area was shown to have poor groundwater quality with significant amounts of pollutants such as NO3, Pb and Cd leading to environmental and health concerns.

Two severe accident scenarios are investigated in this paper as they have never been considered previously in the safety analysis report (SAR) of the Congo TRIGA Mark II research reactor (TRICO II) in Kinshasa, the Democratic Republic of Congo. The source term is derived from the reactor core after two postulated accidents: (1) a large plane crash with total destruction of the reactor building and (2) full damage of one fuel element while the reactor building remains intact. Total effective dose (TED), after core inventory, and dose profiles to human organs are derived to assess the operational safety of the reactor. Results from the study will be used to upgrade the current SAR of the reactor as the reactor safety and licensing concepts are changing over the years; the knowledge and lessons learned from the past experience are being updated accordingly with the available data. TEDs to workers of the facility show that higher values are obtained at areas near the source term at the time of the plane crash accident, which dies out as quickly as the plume is carried away following predominant meteorological conditions at the site. The situation with one fuel element totally damaged poses no threat as far as radiation protection is concerned and reveals a maximum TED of 1.30×10−7  mSv at 100 m from the reactor core. This shows that the operation of this type of research reactor is reliable and safe.

In the sparsely investigated region of the Congo Basin (CB), flood seasonality and flood regime shift are established through relative frequency, cluster analysis, directional statistics, and non-overlapping block methods based on block maxima and peak over threshold (POT) series. Two months of significantly rich floods are observed at all gauging stations. The spatial distribution of floods presents three patterns: the north and northwest pattern, south and southeast pattern, and west/east pattern. It is observed that unimodal flood distribution is coherent in the northern and southern parts, as opposed to the bimodal flood distribution observed along the large band of the Equator from west to east of the basin. The time lag of flood indices suggests that the flood regime is not stationary. In addition, the time series show periods of high flooding, with POT frequencies and amplitudes higher during the 1960s and early 1970s than any other time period.