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2 In regard to the North Decline sumps, these two structures were permitted as alternate sediment control methods in conjunction with "small area exemptions". Rule 4.05.2(3) allows the Division the discretion to grant exemptions from the requirement to pass disturbed area runoff through a sediment pond when the operator demonstrates that ponds are not necessary for runoff to meet effluent limits. The operator made the required demonstration by designing the sumps to totally contain runoff from a 25-year, 24- hour event. The Division approved the exemption. Therefore, no sediment pond was required or built, as per Rule 4.05.2(3). Rule 4.05.6 is not applicable to these structures. Furthermore, as indicated in Table 2.05.3M of the Roadside permit, these sumps were excavated below grade. Consequently, they have no dams or embankments. Therefore, the design and certification requirements of 4.05.9(2), (3), (9), (10) and are not relevant. The applicable portions of Rule 4.05.9 have been complied with. The AFO inspection report correctly indicates that these structures are the primary means of sediment control. The conclusion is then made that, because the sumps are the primary means of treatment and they impound water, they must therefore be sediment ponds.In deriving this conclusion, the fact that the structures are part of an SAE (which, by definition does not require a sediment pond) and that they are excavated structures with no embankments is overlooked. The AFO inspection report also indicates that the structures should be certified by a registered professional engineer. Rule 4.05.9(10) requires that, "All dams and embankments that do not meet the size or other criteria of 4.05.9(3) shall be certified by a qualified registered professional engineer". The structures in question have no dams or embankments since they are excavated below grade. Therefore, no certification is required by the regulations. In summary, the Division and the mine operator consulted each other in regard to a number of alternative approaches to treating runoff from the reclaimed North Decline area prior to its reclamation. It was agreed that excavated impoundments were an appropriate form of best technology currently available for this site. Because of the topography and the small area involved, the Division deemed that designation as a "small area exemption " was more effective than installation of sediment ponds. The Division correctly interpreted its regulations and applied the relevant portions of Rule 4.05 (Specifically 4.05.2(3) and 4.05.9(5)(b), (6), (7), (8), (12) and (13).) Therefore, enforcement action is not appropriate.