1986 is right around the time of Black Ops Cold War, so what if we ventured into this reactor, perhaps because the cause was actually a Dark Aether portal?
If you've been living under a rock and don't know what the Chernobyl Disaster was, in 1986, a nuclear reactor in Northern Ukraine exploded, and to this day, the area is radioactive. Dark Aether anomalies are opening up across the world, from Poland to Vietnam, but where will Weaver send his rag-tag team of operators next? I'd throw Chernobyl in as a perfect place to go. Call of Duty: Black Ops Cold War is set in the 1980s, and the Zombies mode has taken advantage of this.