(a) A person may use an electronic document to satisfy a federal reporting requirement or otherwise substitute for a paper document or submission permitted or required under other provisions of Title 40 only if:

(1) The person transmits the electronic document to EPA's Central Data Exchange, or to another EPA electronic document receiving system that the Administrator may designate for the receipt of specified submissions, complying with the system's requirements for submission; and

(2) The electronic document bears all valid electronic signatures that are required under paragraph (b) of this section.

(b) An electronic document must bear the valid electronic signature of a signatory if that signatory would be required under Title 40 to sign the paper document for which the electronic document substitutes, unless EPA announces special provisions to accept a handwritten signature on a separate paper submission and the signatory provides that handwritten signature.

(a) Except as provided under paragraph (b) of this section, whenever EPA plans to change Central Data Exchange hardware or software in ways that would affect the transmission process, EPA will provide notice as follows:

(1) Significant changes to CDX: Where the equipment, software, or services needed to transmit electronic documents to the Central Data Exchange would be changed significantly, EPA will provide public notice and seek comment on the change and the proposed implementation schedule through the Federal Register;

(2) Other changes to CDX: EPA will provide notice of other changes to Central Data Exchange users at least sixty (60) days in advance of implementation.

(3) De minimis or transparent changes to CDX: For de minimis or transparent changes that have minimal or no impact on the transmission process, EPA may provide notice if appropriate on a case-by-case basis.

(b) Emergency changes to CDX: Any change which EPA's Chief Information Officer or his or her designee determines is needed to ensure the security and integrity of the Central Data Exchange is exempt from the provisions of paragraph (a) of this section. However, to the extent consistent with ensuring the security and integrity of the system, EPA will provide notice for any change other than de minimis or transparent changes to the Central Data Exchange.