40 CFR § 63.1945
When do I have to comply with this subpart?
June 9, 2020
(a) If your landfill is a new affected source, you must comply with this subpart by January 16, 2003, or at the time you begin operating, whichever is later.
(b) If your landfill is an existing affected source, you must comply with this subpart by January 16, 2004.