40 CFR 63.5430 - What records must I keep?
(a) You must keep the plan for demonstrating compliance as required at § 63.5325 onsite and readily available as long as the source is operational. If you make any changes to the plan for demonstrating compliance, then you must keep all previous versions of the plan and make them readily available for inspection for at least 5 years after each revision.
(b) You must keep a copy of each notification and report that you are required to submit in accordance with this subpart.
(c) You must keep records of performance tests in accordance with this subpart.
(d) You must record and maintain a continuous log of finish usage as specified at § 63.5335(b).