A submerged vessel from the Cold War era, specifically a nuclear submarine, is subtly disseminating radioactive elements into the profound and unlit depths of the Norwegian Sea, as confirmed by a recent comprehensive survey.
The Soviet submarine designated K-278 Komsomolets met its demise following an internal conflagration in April of 1989. At the time of its sinking, it carried not only its nuclear propulsion system but also a payload of two nuclear-tipped torpedoes.
Current findings from a specialized investigation, spearheaded by marine radioecologist Justin Gwynn associated with the Fram Centre and the Norwegian Radiation and Nuclear Safety Authority, indicate that the gradual deterioration of the submarine has not yet precipitated the catastrophic environmental damage it is capable of inflicting.
While the torpedoes remain hermetically sealed, the submarine’s nuclear reactor is undergoing degradation, intermittently expelling discernible plumes of radioactive substances into the aquatic environment, as reported by Gwynn and his research associates in a newly published academic paper.
“Radioactive discharges originating from the reactor have been ongoing for over three decades,” the scientific team notes. However, “there is minimal evidence suggesting any significant accumulation of radionuclides in the immediate vicinity of the submarine, as the dispersed radionuclides appear to be rapidly diluted within the surrounding oceanic water column.”
The resting place of the Komsomolets represents a profound tragedy, leading to the loss of most of its crew and leaving an enduring radioactive hazard situated 1,680 meters (5,510 feet) beneath the surface of the Norwegian Sea, in perpetual darkness.
Continuous observation of the wreck since the 1990s has provided evidence of intermittent radioactive seepage. Initial assessments revealed considerable damage to the submarine, with its hull fractured and seawater having established contact with the nuclear torpedoes.
Substantial remedial efforts were undertaken in 1994 to secure the compromised torpedo compartment, and no indications of weapons-grade plutonium escaping into the surrounding marine ecosystem have been detected.
Nevertheless, ongoing annual inspections conducted by Norwegian authorities have identified radioactive cesium isotopes present in the water proximate to the submarine.
At that juncture, it was apparent that the submarine was experiencing leaks. Currently, Gwynn and his collaborators have concluded their analysis of the gathered data, successfully quantifying the leakage, identifying its origin, and assessing its impact on the benthic ecosystem.
The research team ascertained that the leakage is not a continuous process but rather occurs in discrete episodes emanating from specific points along the hull, including a ventilation conduit and the vicinity of the reactor compartment. Remotely Operated Vehicle (ROV) recordings captured visual evidence of plumes emanating into the ocean.
Analysis of samples collected from these plumes revealed the presence of strontium, cesium, uranium, and plutonium isotopes. In close proximity to the wreck itself, the researchers report, concentrations of strontium and cesium were found to be “400,000 and 800,000 times greater, respectively, than the standard levels of these radionuclides in the Norwegian Sea.”
The elevated concentrations and specific ratios of uranium and plutonium, according to the researchers’ assessment, also point to the active corrosion of the nuclear fuel contained within the reactor.
However, mere meters away from the submarine, radioactive contamination levels diminish significantly, suggesting that these isotopes undergo rapid dispersal.
Furthermore, samples taken from the sponges, corals, and anemones inhabiting the wreck exhibit marginally elevated levels of radioactive cesium – yet, there are no discernible signs of malformations or other pathological conditions. The adjacent seabed sediment also shows minimal evidence of radioactive contamination.
Concurrently, the prior interventions to seal the torpedo compartment remain effective.
This constitutes a disquieting revelation. It suggests that the actual detrimental impact from the wreck has been relatively limited to date, despite our limited understanding of marine life in such extreme depths.
Simultaneously, a compromised submarine resting on the seabed is destined to experience further structural degradation over time, rendering the long-term prognosis for the Komsomolets a source of ongoing concern.
The sunken vessel resides in the frigid, high-pressure environment of the bathypelagic zone – a region exceedingly difficult for human access, where any repair operations necessitate meticulous planning and sophisticated engineering.
While it is reassuring that the prior repair work has held, the wreck persists as a latent threat requiring continuous oversight, as emphasized by the researchers.
“Further investigations ought to be conducted to elucidate the mechanisms driving the observed releases, the corrosion processes affecting the reactor, and their implications for future discharges and the ultimate fate of the residual nuclear material within the reactor,” they advocate.
“The Komsomolets presents an unparalleled opportunity to comprehend the risks and ramifications associated with releases from other submerged or discarded reactors in the Arctic, as well as the potential hazards stemming from any future incidents involving nuclear-powered vessels and other forms of maritime nuclear technology.
“Consequently, it is imperative that ongoing monitoring of the situation and the condition of the submarine is diligently maintained.”
These scientific findings were formally published in the journal PNAS.
