1) Seal off the area with concrete walls
2) Have Army and Marines stationed all over the wall
3) Send Rangers, Force Recon, SEALs, Delta Force, and anyone else from SOC that I'm forgetting
-Mission to kill zombies, restrain civilians for helicopter evac. Capture zombies optional
-Rescued sent to quarantine for three days, individual cells
-Zombies kept for study under heavy guard (i.e. two soldiers with rifles aimed at it at all times)
-Immune civilians (infected but not turning) kept for study under good conditions (outside contact, treated well, etc.)
4) Once all civilians and zombies are removed, disinfect the area (virus cure, flamethrowers, whatever works)