40 CFR § 1054.335
How do I ask EPA to reinstate my suspended certificate?
June 9, 2020
(a) Send us a written report asking us to reinstate your suspended certificate. In your report, identify the reason for noncompliance, propose a remedy for the engine family, and commit to a date for carrying it out. In your proposed remedy include any quality control measures you propose to keep the problem from happening again.
(b) Give us data from production-line testing that shows the remedied engine family complies with all the emission standards that apply.