map : bm_c2a4c at: 325 x, -466 y, 329 z
setpos 325.749268 -466.202820 329.757935;setang 33.823887 -177.572647 0.000000
Basically, conveyor belts that are supposed to be “one way” aren’t. When you first enter the Refuse Processing area with the many levels of conveyor belts, there’s a belt coming out of a wall with a sticky mine in it. There are numerous holes like this, with one that you can see the next section of the level though. You can’t go into the hole the conveyor belt is coming out of because the hole is too small and you have to duck. If you duck, you move slower and so can’t move fast enough to make progress against the belt. Instead, you have to go along the belt and into a control room where you move a hanging platform and open a gate to reach the other side of the mined belt.
You don’t have to. Simply walk up to the “small” hole with a conveyor belt coming out of it, crouch and start jumping. You move forward faster while jumping and can thus make it through the wall, skipping a good third of that section. You can go into all of those conveyor belt holes, in fact, but the others don’t lead anywhere important.
edit
No screenshot as my picture host is being difficult.