Let’s posit a genuine Zombie Apocalypse.
I can think of one dead-easy solution: Zombie corrals. Arrange a pre-fab concrete-wall building. Add several entrances that are one-way. Attractants (light, noise) clearly visible from outside of the entrances.
Zombies lurch in, but they don’t lurch out. Then, depending on type of zombie, flood the corral with the appropriate agent.
If biological/viral. just flood the corral with Carbon Monoxide: if mystic/undead, let loose flamethrowers, or even an overhead gasolene/kerosene sprinkler system, and a igniter in the walls, and it’s Zombie Flambe. . . .
IF you don’t have time to build a pre-fab,lure them to a nearby quarry pit, and then deal with them. . .
