All Persons subject to these regulations shall retain and preserve for no less than three years any records, books, documents, memoranda, reports, correspondence, and any and all summaries thereof, relating to operation, maintenance, monitoring, sampling, and chemical analysis made by or on behalf of a person in connection with its discharge. All records which pertain to matters which are the subject of Administrative Adjustment or any other enforcement or litigation activities brought by the Director pursuant to this Chapter shall be retained and preserved by the Person until all enforcement activities have concluded and all periods of limitation with respect to any and all appeals have expired.