hey guys i think i found how to do the step you guys are on about. I found a gramophone somewhere, sorry but i cant remember where, then where the pack a punch is i put it on a type of workbench. Then Samantha said about how there needs to be some kind of music to reveal the passage or something along those lines. I went back outside then by complete mistake picked up a disk, the place where i got it was leaving the excavation site and going right for a couple of steps. I went back underneath the excavation site, played the disk and what do you know? That big blue circle rumbled and a giant passageway opened underneath it! There is a huge, cylindrical type blue thing through the middle, and i'm exploring the place now, ill keep you posted!
-Pat