On 4 March 2012, a series of explosions occurred in the Regiment Blindé munitions depot in the eastern portion of Brazzaville, Congo. The explosions caused disastrous damage to humans and surrounding buildings and infrastructure in the perimeter of 1.5km. Over 250 people were reported dead, over 3,000 injured and approximately 20,000 were displaced to emergency shelters. Due to the shock wave, an inestimable amount of unexploded ordnances (UXOs) were spread throughout the surrounding city. Several tons of explosive agents, rifle and artillery ammunition and possibly rocket fuel were reportedly detonated in the blast.
On 5 March 2012, an official request for environmental emergency response services was made by the United Nations Resident Coordinator (UN RC). The United Nations Office for the Coordination of Humanitarian Affairs (OCHA) through their Emergency Services Branch subsequently coordinated the deployment of an UN Disaster and Coordination (UNDAC) Team to undertake a rapid environmental emergency assessment and assist with the coordination of international assistance. The team was comprised of UNDAC trained environmental emergency experts from a variety of environmental backgrounds. The scope of the mission was to assess the secondary impacts on industrial facilities for damage and possible risks to people and environment, and to provide scientific information in relation to the extent and nature of contamination and exposure to chemical agents resulting from the blast with the aim to assist the decision-making and priority-setting of the authorities and other actors for follow-up activities at the affected site.
The main conclusions found no industrial facilities visited posed a secondary risk, which could create vulnerability to chemical spills or explosions, and additional contamination to the surrounding soils and water in the area. Furthermore, no indicators were found that significant amounts of heavy metals or explosive agents were distributed throughout the city. While trace amounts of chemicals were detectable in samples from the zone of impact, and were above the normal background levels, they do not exceed the threshold values as determined by Swiss law. However, due to the limited number of samples taken from the large-area zone of impact, “hot spots” could be present in the area and not captured in the sampled data. Therefore, further analysis in this area is warranted once the debris and remaining UXOs are removed from the area.
No contamination was present in the water samples taken however, due to the limited number of samples analyzed, a better knowledge of the drinking water supply would be necessary to properly assess the contamination risk to the surrounding population. For instance, if the drinking water supply is fed by groundwater from the zone of impact, a possible risk of exposure could be present.
Detailed recommendations have been provided in the report available here, which feature the immediate measures to be taken for reducing exposure risk from UXOs and possible further contamination through the leaching of toxic substances.