Soviet naval base 569 at Andreev Bay, on the western shore of the Zapadnaya Litsa inlet, entered service in 1961 as a repository for spent nuclear fuel from the Northern Fleet's submarine reactors. Building #5 housed two pools, each 60 meters long, 3 meters wide, and 6 meters deep, designed to store spent fuel assemblies encased in steel drums. Each drum held five to seven fuel assemblies and weighed 350 kilograms when loaded. The drums were supposed to hang suspended underwater from massive chains, spaced precisely to prevent an uncontrolled nuclear chain reaction. The water itself served as biological shielding. In practice, the crane mechanism was unreliable, and drums regularly fell from their chains and piled up at the bottom of the pools. The base eventually held some 22,000 spent nuclear fuel assemblies, making it one of the largest concentrations of nuclear waste anywhere on Earth.

The right-hand pool in Building #5 began leaking in February 1982. Inspecting the cracks required diving into the pool, which was impossible: gamma radiation levels near the submerged drums reached 17,000 roentgens per hour, a dose that would kill a person in minutes. After the flour failed, engineers detected icing on the building's exterior, estimating the leak at 30 liters per day. By April, it had risen to 150 liters daily. Six hundred cubic meters of concrete were poured into the basement. The leak continued. By September, it reached a catastrophic 30 tonnes per day, threatening to expose the tops of the fuel assemblies and irradiate anyone in the building. Iron-lead-concrete covers, weighing thousands of tonnes in total, were built over the pool. In November, the weight of those covers caused the building itself to sag, and the left-hand pool developed its own leak of 10 tonnes per day. It was later determined that only luck prevented the entire building from collapsing.

The cleanup, which ran from 1983 to 1989, involved approximately 1,000 people working in conditions that no safety protocol had anticipated. Workers cut windows into the protective covers with welding torches so they could lower grabbing devices to retrieve drums from the pool floor. One day a starshina first class stepped onto an iron sheet covering a window, the sheet gave way, and he plunged into the radioactive water, his legs caught beneath nuclear waste drums. A starshina second class immediately jumped in after him. They surfaced moments later, drenched in radioactive water. Their dosimeters sank with them, so the actual radiation dose they received was never measured. Both men had all body hair removed, slept in isolation, and received their food through rubber gloves because their bodies had become sources of gamma radiation. Vladimir Konstantinovich Bulygin, who directed the fleet's radiation accident response, received the Hero of the Soviet Union decoration for his role in the cleanup.

Perhaps the most chilling detail of the cleanup came during the transfer of fuel drums from Building #5 to dry storage containers. The containers, three underground steel cylinders each 18 meters in diameter, had originally been designed as water filtration structures. After being repurposed, their concrete covers were broken open for loading, leaving them exposed to Arctic weather. When drums were lowered into the cells, displaced water instantly vaporized from the fuel assemblies' heat, sending radioactive steam across the entire base. Damaged cells spilled their contents, and working sailors shoveled loose nuclear fuel into the storage pipes with ordinary shovels. These accumulations repeatedly reached critical mass, triggering spontaneous uncontrolled chain reactions that produced the distinctive blue-green glow of Cherenkov radiation and a buzzing sound that quickly faded. Physicist Senior Lieutenant Leonid Grigorievich Konobritski, who served in Building #5, confirmed that the flashes were indeed chain reactions. By December 13, 1989, all fuel had been removed except for 25 drums stuck at the bottom of the left-hand pool, which were buried in boron to absorb neutron emissions. Building #5 was never used again.