DESPITE RECENT RAINS MONTEREY AREA FIREFIGHTERS BATTLED A GRASS FIRE YESTERDAY. THE FIRE BROKE OUT IN A FIELD NEAR OLMSTEAD ROADAND VIA MALPASO ABOUT 2 P-M AND BURNED 3 ACRES BEFORE FIRE CREWS EXTINGUISHED THE BLAZE . THE FIRE IS BELIEVED TO HAVE BEEN STARTED BY MECHANICAL EQUIPMENT.