^a This table is provided as a matter of convenience and is not controlling in determining whether a MSW landfill is subject to the Federal plan. A MSW landfill is subject to this Federal plan if it commenced construction before May 30, 1991 and has not been modified or reconstructed on or after that date and is not covered by an approved and currently effective State or Tribal plan.

^b The State plan is expected to become effective on the date indicated. However, if the State plan does not become effective on the date indicated, the Federal plan applies until the State plan becomes effective.