45 CFR §670.15

1. (a)The Director may modify, suspend, or revoke, in whole or in part, any permit issued under this subpart:
   1. (1)In order to make the permit consistent with any change to any regulation in this part made after the date of issuance of this permit;
   2. (2)If there is any change in conditions which make the permit inconsistent with the purpose of the Act and the regulations in this part; or
   3. (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.
2. (b)Whenever the Director proposes any modifications, suspension, or revocation of a permit under this section, the permittee shall be afforded 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.
3. (c)Notice of the modification, suspension, or revocation of any permit by the Director shall be published in the Federal Register, within 10 days from the date of the Director's decision.