(a) At any time prior to the issuance of a complaint seeking a civil penalty under any of the Acts listed in § 70.1, the Administrator, in his discretion, may enter into a stipulation with any person in which:

1. (1) The Administrator or the Administrator's delegate gives notice of an apparent violation of the Act, or the regulations issued thereunder, by such person and affords such person an opportunity for a hearing regarding the matter as provided by the Act;
2. (2) Such person expressly waives hearing and agrees to pay a specified penalty within a designated time; and
3. (3) The Administrator agrees to accept the penalty in settlement of the particular matter involved if the penalty is paid within the designated time.