These textures are translations of the textures at http://jitit.com/golgotha/textures/Page.html.  According to that website, they may be used freely in any way.  If you do use these textures, please give credit to that website, since the people who originally took the pictures that became these textures obviously worked really hard.  
-Nemesis, pistol4@earthlink.net, who translated these textures into .wals.