THE LOUDEN NELSON COMMUNITY CENTER IN SANTA CRUZ WAS EVACUATED FOR A SHORT TIME YESTERDAY. ABOUT 50 PEOPLE WERE DIRECTED TO LEAVE THE BUILDING, DUE TO THE STRONG ODOR OF NATURAL GAS. A GAS LEAK IN THE KITCHEN TURNED OUT TO BE THE CULPRIT. FIREFIGHTERS SHUT OFF THE GAS, AND P.G.& E. WORKERS FIXED THE LEAK. EVERYONE WAS ALLOWED TO GO BACK INTO THE BUILDING SHORTLY BEFORE NOON.