(a) Following completion of the post-closure care maintenance period for each municipal solid waste landfill unit, the owner or operator shall submit to the executive director for review and approval a certification, signed by an independent licensed professional engineer, verifying that post-closure care has been completed in accordance with the approved post-closure plan. The submittal to the executive director shall include all applicable documentation necessary for the certification of completion of post-closure care.(b) Upon completion of the post-closure care period for the final unit at a facility, the owner and operator shall also submit to the executive director a request for voluntary revocation of the facility permit.