30 C.F.R. § 1241.52
(a) If you do not correct all of the violations that we identified in the NONC within 20 days after the date on which you are served the NONC, or any longer period that the NONC specifies for correction, then we may send you an FCCP.
(1) The FCCP will state the amount of the penalty that you must pay. The penalty will:
(b) If you do not correct all of the violations identified in the NONC within 40 days after you are served the NONC, or within 20 days following the expiration of any period longer than 20 days that the NONC specifies for correction, then we may increase the penalty to a maximum of $15,628 per day for each violation identified in the NONC that you have not corrected. The increased penalty will:
[81 FR 50316, Aug. 1, 2016, as amended at 82 FR 18860, Apr. 24, 2017; 83 FR 2909, Jan. 22, 2018; 84 FR 8418, Mar. 8, 2019; 85 FR 7223, Feb. 7, 2020; 86 FR 7810, Feb. 2, 2021; 87 FR 1673, Jan. 12, 2022; 88 FR 2522, Jan. 17, 2023; 89 FR 3886, Jan. 22, 2024; 90 FR 1879, Jan. 10, 2025]