|(a) The voluntary cleanup agreement must be signed by the applicant and the executive director or his representative prior to initiation of any response action being implemented, with the exception of emergency measures which should be coordinated with the appropriate emergency response authorities. However, for response actions initiated or completed prior to the effective date of these rules, the executive director at his discretion may allow sites to enter the Voluntary Cleanup Program. After the effective date of these rules, persons initiating response actions prior to a signed Voluntary Cleanup Agreement may not enter the Voluntary Cleanup Program. A certificate of completion may not be issued for sites which have received agency approval for response actions completed prior to the effective date of the rule if: (1) the action did not address all contaminants or contaminated media within the site or partial response action area;
(2) contaminant management practices were initiated or changed since the previous approval date; or (3) regulatory requirements have changed since the approval date. (b) In the case of partial response actions, the commission retains the authority to issue an enforcement action regarding releases or contamination not addressed by the partial response action.