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. . . Alluvial Fan Flooding (Active)-Flooding that occurs only on alluvial fans and is characterized by flow path uncertainty so great that this uncertainty cannot be set aside in realistic assessments of flood risk or in the reliable mitigation of the hazard. An active alluvial fan flooding hazard is indicated by three related criteria: (1) flow path uncertainty below the hydrographic apex; (2) abrupt deposition and ensuing erosion of sediment as a stream or debris flow loses its ability to carry material eroded from a steeper, upstream source area; and (3) an environment where the combination of sediment availability, slope, and topography creates an ultrahazardous condition for which elevation on fill will not reliably mitigate the risk. Alluvial Fan Flooding (lnactive)-Flooding that is similar to traditional riverine flood hazards, but occurs only on alluvial fans. Inactive alluvial fan flooding is characterized by flow paths with a higher degree of certainty in realistic assessments of flood risk or in the reliable mitigation of the hazard. Unlike active alluvial fan flooding hazards, an inactive alluvial fan flooding hazard is characterized by relatively stable flow paths. However, like areas of active alluvial fan flooding, inactive alluvial fan flooding, may be subject to sediment deposition and erosion, but to a degree. that does not cause flow path instability and uncertainty. Alphanumeric Data-Data consisting of both letters and numbers, and possibly symbols such as punctuation marks. American Standard Code for Information Interchange (ASCH)--A popular standard for the exchange of alphanumeric data. Appeal-The formal objection to proposed or proposed modified Base Flood Elevations (BFEs ),. submitted by a community official or an owner or lessee of real property within the community during the statutory 90-day appeal period. An appeal must be based on data that show the proposed or proposed modified BFEs are scientifically or technically incorrect. Appeal Period-The statutory period, beginning on the date of second publication of proposed BFEs and/or proposed modified BFEs in the local newspaper, during which community officials or owners or lessees of real property within the community may appeal proposed or proposed modified BFEs by submitting data to show those BFEs are scientifically or technically incorrect. Application/Certification Forms-The comprehensive, easy-to-use forms that were implemented by FEMA in October 1992 to facilitate the processing of requests for revisions or amendments to National Flood Insurance Program maps. Approved Model--A numerical computer model that has been accepted by FEMA for use in performing new or revised hydrologic or hydraulic analyses for National Flood Insurance TERMS-2 CTP COOTwt,Jimg klll/Tlcat PdrfllClf)