Fixes runtime

Fixes the other runtime in #9310

code/modules/recycling/disposal.dm

@@ -544,16 +544,20 @@
 	proc/move()
 		var/obj/structure/disposalpipe/last
 		while(active)
+			sleep(1)		// was 1
+			if(!loc) return // check if we got GC'd
+
 			if(hasmob && prob(3))
 				for(var/mob/living/H in src)
 					if(!istype(H,/mob/living/silicon/robot/drone)) //Drones use the mailing code to move through the disposal system,
 						H.take_overall_damage(20, 0, "Blunt Trauma")//horribly maim any living creature jumping down disposals.  c'est la vie
 
-			sleep(1)		// was 1
-
 			var/obj/structure/disposalpipe/curr = loc
 			last = curr
 			curr = curr.transfer(src)
+
+			if(!loc) return //side effects
+
 			if(!curr)
 				last.expel(src, loc, dir)