EARTH POLYCHROMATIC IMAGING CAMERA (EPIC) LEVEL 1 (L1) DATA ARE THE BASIS FOR THE EPIC LEVEL 2 (L2) PRODUCTS SUCH AS OZONE CLOUD MAPS AND VEGETATION MAPS. ANY SYSTEMATIC ERROR IN THE L1 DATA EITHER FROM INCOMPLETE PRE-LAUNCH CALIBRATION OR FROM UNDETECTED CALIBRATION CHANGES ON ORBIT WILL DIRECTLY AFFECT ALL L2 PRODUCTS. THIS PROPOSAL AIMS TO MAINTAIN AND ENHANCE THE CURRENT IN-FLIGHT CALIBRATION OF EPIC BASED ON DETAILED ANALYSIS OF IN-FLIGHT DATA.. .BASED ON OUR ANALYSIS OF ERROR SOURCES WE PROPOSE THREE WORK PACKAGES TO ENSURE HIGH QUALITY EPIC DATA OVER THE LIFETIME OF THE MISSION: ...CALIBRATION AND MAINTENANCE OF DARK COUNT MAPS AND BAD PIXEL LISTS ...DETECTOR FLAT FIELD CORRECTION ENHANCEMENT ...EPIC RELATIVE RADIOMETRIC CALIBRATION TRENDING. ..IF NOT PROPERLY MAINTAINED EACH OF THESE ITEMS WILL SIGNIFICANTLY IMPACT THE QUALITY OF EPIC S L1 AND L2 SCIENCE DATA PRODUCTS. THE INPUT FOR OUR PROPOSED CALIBRATION AND MAINTENANCE WORK ARE THE EXISTING EPIC CALIBRATION INFORMATION AND THE OPERATIONAL EPIC IMAGES FROM EARTH AND MOON INCLUDING WEEKLY DARK IMAGES. THE OUTPUT OF OUR PROPOSAL WILL PROVIDE IMPROVEMENTS TO THE EPIC CALIBRATION FILES AS NEEDED. .