Something must have been lost in translation. Obviously, no one is firing on the site now.
I think it's just Haaretz, firing on Israel.
I’m guessing that it is a military base. And perhaps includes areas with weapons training (artillery, tanks, etc.)
“With the cooperation of the Israeli military, excavations have revealed an actual metropolis, albeit not that civilians can visit it on a whim, it being in the firing zone. “We can say right now that it’s a huge place, over 450 dunams [111 acres] in area,” Erickson-Gini says.”