(a) With the exception of subsections (b) and (c) of this section, an application for renewal must be submitted at least six months, but no earlier than 18 months, prior to expiration of the permit or the permit will expire.(b) With executive director approval, the application may be submitted before or after the time period specified in subsection (a) of this section.(c) A renewal application with appropriate fee may be submitted at the same time as an amendment application to modify an existing facility as long as it is submitted not more than three years before the permit's expiration date and the amendment is subject to public notice requirements under Texas Health and Safety Code, §382.056, Notice of Intent to Obtain Permit or Permit Review; Hearing.(d) Any permit issued:(1) before December 1, 1991, is subject for review 15 years after the date of issuance;(2) on or after December 1, 1991, is subject for review every ten years after the date of issuance; or(3) at non-federal sources on or after December 1, 1991, may, for cause, contain a provision requiring renewal between five and ten years.