1830 Day shift blast crew reported fall of ground in L1N preventing egress after 1231 and 1202 shot ore rounds. GF's investigated & reported to management & MSHA as ground support & access was compromised in a small area of the ramp. 3 miners turned off water, air & discharge. UG electricians cut power on the 1308 cable. Area secured, roped off near 1202 sump and 1260 NZ raise.