Within thirty days after receiving a petition for reconsideration under Sec. 66.52 the Administrator shall:
(a) Accept the penalty calculation of the owner or operator to the extent the Administrator concludes it is correct; or
(b) Grant a hearing to the extent he does not conclude that the petition is correct. [45 FR 50110, July 20, 1980, as amended at 50 FR 36734, Sept. 9, 1985]