At nine in the morning on Thursday, there was an explosion at a coastal missile testing ground not far from the town of Nyonoksa in Russia’s Arkhangelsk province. Shortly thereafter, there were reports of a fire on board a nearby ship, and the local authorities announced that medical aircraft had been dispatched to the site of the incident.
“At a Russian Defense Ministry testing ground in the Arkhangelsk province, during the testing of a liquid rocket propulsion system, there was an explosion, and the item caught fire,” the department reported. “There were no emissions of hazardous substances into the atmosphere, and background radiation is at normal levels. Two people were killed and six were injured. These were representatives of the ministry and of the developer company. They have all been hospitalized.”
The Defense Ministry did not provide any other details about the incident. However, reports appeared in the local media claiming that a total of 15 people had been injured and that several of them were in a critical condition. Some of the wounded were taken to the Volosevich Hospital in Severodvinsk, others to the Arkhangelsk Regional Clinic Hospital.
Some time later, there were reports of increased radiation levels in Severodvinsk.
Over the course of an hour and a half, the background radiation reached three times its normal level, although it did not constitute a health risk to civilians, explained Valentin Magomedov, head of the city’s civil protection department.
“In the period between 11:50 and 12:20, we detected an increase in the background radiation to 2 microsieverts per hour. Thereafter, the level began to decline rapidly… At present, the radiation level is 0.1 microsieverts per hour, and there is no threat to the civilian population,” he observed. As a reference, patients can be exposed to up to 3.3 millisieverts per hour during X-rays of the gastrointestinal organs.
Later on Thursday it was learned that the port administration of the western Arctic had closed off a region of the White Sea’s Dvina Bay to navigation in connection with the incident. The warning was displayed on the port administration’s official website, and instructions were sent to vessels in the area. According to the civilian sailors, the closure was requested by the military.
A military source told the newspaper Kommersant that the explosion was caused by rocket fuel – unsymmetrical dimethylhydrazine – coming into contact with an oxidant. It is possible that tons of this extremely toxic substance ended up in the water. In this case, the closure of the area could be necessary to prevent the poisoning of the locals, who traditionally rely on fishing for their livelihood. The military will also need time to locate and collect surviving fragments for the purpose of investigating the incident.