EACH SECTION OF THIS MASS TRANSIT UNIT COMPLEMENTS THE OTHER IN THE DEPARTMENT'S DETERMINED EFFORTS TO ERADICATE CRIME ON THE CHICAGO TRANSIT AUTHORITY'S SURFACE, UNDERGROUND, AND ELEVATED STATIONS. A COMBINATION OF HIGHLY MOBILE UNIFORM PATROL AND PLAINCLOTHES TACTICAL TEAMS CHECKING THE STATIONS AND RIDING THE TRAINS KEEPS THE WOULD-BE MUGGER OFF BALANCE AND UNSURE. EXPERIMENTAL PROGRAMS PLANNED AND/OR TRIED OUT INCLUDE THE USE OF K-9 TEAMS TO PATROL THE SYSTEM AND THE INCREASED USE OF EMERGENCY TELEPHONES ON EL PLATFORMS AND CLOSED CIRCUIT TELEVISIONS AT HIGH RISK LOCATIONS....ELW