A certificate automatically shall be null and void if: Construction or other preparation of the site for its intended use of the facility for which the certificate was issued has not commenced within 2 years following issuance of the certificate; or The facility has not commenced operation within 4 years following issuance of the certificate. The Board may extend the time limits imposed under subsection (a) of this section if the certificate holder: Applies to the Board for an extension; and Shows good cause for allowing the extension.