(a) The Director may modify, suspend or revoke, in whole or in part, any permit issued under this part:

(1) In order to make the permit consistent with any change to any regulation in this part made after the date of issuance of the permit;

(2) If there is any change in conditions which makes the permit inconsistent with the Act and any regulation in this part; or

(3) In any case in which there has been any violation of any term or condition of the permit, any regulation in this part, or any provision of the Act.

(b) The Director shall review all unexpired permits issued under this part at least biennially to determine whether those permits should be modified, suspended or revoked as set forth in paragraph (a) of this section.

(c) Whenever the Director proposes any modifications, suspensions or revocations of a permit under this § 671.10, the permittee shall be afforded the opportunity, after due notice, for a hearing by the Director with respect to such proposed modification, suspension, or revocation. If a hearing is requested, the action proposed by the Director shall not take effect before a decision is issued by him after the hearing, unless the proposed action is taken by the Director to meet an emergency situation.

(d) Notice of the modification, suspension, or revocation of any permit shall be published in the Federal Register within 10 days from the date of the Director's decision.