Conditions for environmental resource permit issuance in Rule 40D-4.301, F.A.C, are intended to prevent adverse offsite flooding impacts. Criteria in the BOR provide the basis for meeting the conditions for permit issuance. The BOR identifies the 100 year, 24 hour storm event as the basis for determining the 100 year floodplain and the 25 year, 24 hour storm event for comparing pre- and post-development discharge rates. In certain circumstances, higher flood elevations can occur following more frequent storm events than those specified in the Basis of Review. In those cases, it is desirable to consider other storm events of different frequency or duration to provide reasonable assurance of compliance with the conditions of issuance. The proposed amendments are intended to provide the flexibility to meet the conditions for permit issuance in those cases where basin hydraulics cause higher flood elevations to occur following more frequent storm events than those specified in the BOR.