You must wear the armor of an Orc warrior. It can be obtained from Ur-Thrall after completing the task with the Orc mine (if I'm not mistaken). And one more thing, you're talking about an Ice Location with orcs, right? I just don't know much English
And one more thing, orcs do not need to be killed or contacted in any way. Until the seventh chapter, they don't seem to be needed for anything. Perhaps you should talk to the orc shaman, he is located near the only runestone in the location. Be sure to save before that!
Also, you must have an orc totem, although I still don't remember what it's for, it might come in handy