Conditional Letter of Map Revision Based on Fill (CLOMR-F) - Letter issued by FEMA based on its review of a proposal to build improvements on a site that has been (or will be) graded and filled in order to raise the level of the land above the BFE. A CLOMR-F indicates the map will be revised if the fill and construction are implemented as proposed. CLOMR-Fs do not affect the mandatory purchase of flood insurance requirement for the proposed construction site; to do so, final as-built construction data must be provided to FEMA confirming that the fill and construction were implemented as proposed. FEMA will then issue a final LOMR-F for the site, which can affect the mandatory purchase requirement.