THE GEOLOGIC HISTORY OF VENUS REMAINS PERHAPS THE MOST ENIGMATIC ASPECT OF INNER SOLAR SYSTEM SCIENCE. THE MAGELLAN MISSIONMAPPED ALMOST THE ENTIRE SURFACE OF THE PLANET BUT THE LACK OF DETAILED COMPOSITIONAL INFORMATION BEYOND A FEW PLAINS LANDING SITES THE ATMOSPHERIC FILTERING OF SMALL IMPACTORS THAT HAMPERS REGIONAL AGE ESTIMATION AND THE INHERENT AMBIGUITIES IN GEOLOGIC MAPPINGFROM 100-M SCALE RADAR IMAGES LEAVE OPEN WIDELY DIFFERING POSSIBLE HISTORIES. ONE OF THE MOST FUNDAMENTAL QUESTIONS IS WHETHERVENUS OF SUCH SIMILAR SIZE AND PRESUMABLY HEAT BUDGET TO EARTH HAS ONGOING VOLCANIC ACTIVITY. ORBITAL INFRARED MEASUREMENTS OFFERHINTS OF WEATHERING DIFFERENCES AMONG VOLCANIC FLOWS THAT COULD SUGGEST RECENT ACTIVITY BUT MAPPING OF SURFACE CHANGE OVER TIME ISNEEDED TO PROVE THAT ERUPTIONS ARE ACTUALLY OCCURRING. EARTH-BASED RADAR MAPPING OFFERS THE ONLY CURRENT MEANS TO PROVIDE LONGTERMMONITORING OF MAJOR VOLCANIC PROVINCES ON VENUS. WE PROPOSE TO (1) RECOVER CALIBRATE AND MAP 1988 ARECIBO VENUS RADAR DATAWITH 1-2 KM SPATIAL RESOLUTION AND ARCHIVE THESE DATA WITH THE PLANETARY DATA SYSTEM (PDS) TO PROVIDE THE START OF A LONG-TERM BASEFOR VENUS MONITORING (2) REDUCE NEW VENUS OBSERVATIONS FROM THE 2012 OBSERVING OPPORTUNITY AND DELIVER THESE TO THE PDS AND (3)PERFORM A COMPARISON BETWEEN THE 1988 AND 2012 IMAGES TO SEARCH FOR EVIDENCE OF SURFACE CHANGE. THE RESULTS WILL BE SCIENTIFICALLYSIGNIFICANT IN EITHER PROVIDING OUR FIRST DIRECT DETECTION OF RECENT VOLCANISM ON VENUS OR IN PROVIDING A CONSTRAINT ON RESURFACING RATESIMPLIED BY NO FEW-KILOMETER SCALE SURFACE CHANGE OVER MAJOR REGIONS IN THIS 24-YEAR PERIOD.