Alright, I took a look at it. The reason the texture on the sides of the dumpster were distorted was because their UV faces were
way too undersized (see picture 1). Basically, the small texture areas inside of those two UV faces, (marked 'SIDES' in picture 1) were being stretched and distorted to fill out the dumpster's side faces. All I did to fix it was scale up the UV map for the dumpster's side faces (picture 2). It's also important the UV face resembles the face in the mesh (again, picture 2).
When you unwrap something in the future, try experimenting with the "project from bounds" option; which will unwrap whatever faces you have selected the way you're looking at it. Good luck!
Kravenwolf