Come on now, you all know this serves no purpose other than looks cool and is a place for bad guys to fall into and characters to have to swing across.
Moving/falling into the chasm is instant death with the same effects of being hit be a disintigrator with no chance of a save. A chasm can be crossed using a jet-pack or by a Whistler's puff move action as long as movement does not end over the chasm (killer downdrafts and such.) The chasm does not block LOS.
A bridge can be deployed across the center (between grid 3 and grid 4) from either battlestation with an Engineering skill check vs 8. The bridge may then be used to cross the chasm (as long as it stays deployed.) Retracting the bridge is also an Engineering skill check of 8. Any character on the center square plummets to their demise. Characters on the other squares may make an Athletics skill check vs 11 to jump to an adjacent empty square or they fall to their doom.
Damage to the module will leave the bridge in the current state (either deployed
or retracted.)