This is a scenario in SimCity (1989). Your mission is to clean up after a nuclear meltdown. In the SNES version of this game, the Meltdown is blamed on the simultanious flushing of every toilet in the city during halftime of the 2010 Nintendo Bowl.
The Player has five (5) years to complete the scenario.
In the SNES version of the scenario, holding the L + R buttons at the same time, has the effect of pausing time, giving the player the chance to manually demolish every nuclear plant in the city. Doing so will avoid the meltdown, even if new nuclear plants are built afterwards.
Even if the nuclear meltdown is avoided, Boston suffers from serious problems like crime, high traffic, and poor city planning. Winning the scenario is guaranteed if Boston makes it to Metropolis, but this will take a lot of money to fix.