(b) The Director of the Division of Environmental Quality may forego enforcement action for emissions exceeding any limits established by this part or permit as a direct result of unavoidable upset conditions in the nature of the process, or unavoidable and unforeseeable breakdown of any air pollution control equipment or related operating equipment, or as a direct result of shutdown or startup of such equipment for necessary scheduled maintenance, provided that all reasonable measures have been taken to immediately minimize or eliminate the excess emissions and the following requirements are met:

1. (1) Such occurrence, in the case of unavoidable upset in or breakdown of equipment, shall have been reported to the director by the end of the next business day after the occurrence;

2. (2) The person responsible for such emissions shall submit to the director, at his or her request, a full report of such occurrence, including a statement of all known causes and of the scheduling and nature of the actions to be taken to minimize or eliminate future occurrences, including, but not limited to, action to:

   1. (A) Reduce the frequency of occurrence of such conditions;
   2. (B) Minimize the amount by which said limits are exceeded; and
   3. (C) Reduce the length of time for which said limits are exceeded;

3. (3) In the case of a shutdown for necessary scheduled maintenance, the intent to shutdown shall be reported to the director at least twenty-four (24) hours prior to the shutdown, provided, however, that the exception provided by this section shall only apply in those cases where:

   1. (A) Maximum reasonable effort has been made to accomplish such maintenance during periods of nonoperation of any related source operation; or
   2. (B) It would be unreasonable or impossible to shut down the source operation during the maintenance period;

4. (4)

   1. (A) The person responsible for such emissions shall have submitted to the Division of Environmental Quality for its approval prior to April 30, 1972, either as a part of its permit application if a new source, or on a separate application for existing sources, a schedule of those precautionary devices and procedures designed to minimize such occurrences as are described in subdivision (b)(1) of this section.
   2. (B) Said application shall be on such forms and shall contain such information as the division may reasonably require.
   3. (C) Said application shall have been approved by the division and not therefore withdrawn.
   4. (D) Said equipment is being operated within the terms of the application as approved at the time of such occurrence;

5. (5) Demonstrates to the satisfaction of the division that the emissions resulted from:

   1. (A) Equipment malfunction or upset condition and are not the result of negligence or improper maintenance; and
   2. (B) Physical constraints on the ability of a source to comply with the emission standard, limitation, or rate during startup or shutdown; and
6. (6) All reasonable measures have been taken to immediately minimize or eliminate the excess emissions.