Destroy the Super Mutants at the Watershed

 is a quest in Fallout.

Walkthrough
You need to start this quest before 40 game days have passed or all of the Ghouls in Necropolis will have disappeared.

If you talk to Set, the leader of the Necropolis ghouls and manage not to anger him, he will give you the opprtunity to work for him. He wants you to kill the Super Mutants in the Watershed area. Alternatively, you can just go to the Watershed and kill all the Super Mutants first and then ask Set for payment afterwards. Go to the Watershed through the sewers and prepare for a difficult fight.

There are a total of 6 Super Mutants in the area, including Harry, who is the most heavily armed. Once all are dead, return to Set in the evening to receive your frankly paltry reward. If you then ask Set for the information he also promised tread lightly as he could turn on you for it and you'd have to fight all of his ghouls.

Reward

 * 40 bottle caps.