49 CFR 701.8 - Responses to requests.
(a) Granting of requests. When an initial determination is made to grant a request in whole or in part, the requesting party shall be notified in writing and advised of any fees charged under § 701.11(e). The records shall be disclosed to the requesting party promptly upon payment of applicable fees.
(b) Adverse determination of requests - (1) Types of denials. The requesting party shall be notified in writing of a determination to deny a request in any respect. Adverse determinations or denials of records consist of:
(i) A determination to withhold any requested record in whole or in part;
(ii) A determination that a requested record does not exist or cannot be located;
(iii) A denial of a request for expedited treatment; and
(iv) A determination on any disputed fee matter including a denial of a request for a fee waiver.
(2) Deletions. When practical, records disclosed in part shall be marked or annotated to show both the amount and location of the information deleted.
(3) Content of denial letter. The denial letter shall be signed by the Freedom of Information Officer or designee and shall include:
(i) A brief statement of the reason(s) for the adverse determination including any FOIA exemptions applied in denying the request;
(ii) An estimate of the volume of information withheld (number of pages or some other reasonable form of estimation). An estimate does not need to be provided if the volume is indicated through deletions on records disclosed in part, or if providing an estimate would harm an interest protected by an applicable exemption;
(iii) A statement that an appeal may be filed under § 701.10 and a description of the requirements of that section; and
(iv) The name and title or position of the person responsible for the denial.