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-6- The Division does not agree that the performance of seeding, fertilizing and mulching constitutes successful establishment of revegetation. The Division finds that the revegetation requirements of Rule 3.03.1(2)(b) relate both to ensuring that vegetation is being re-established, and that the vegetation provides erosion control. The Rules and Regulations clearly refer to the establishment of vegetation as a necessary requirement for Phase II bond release, and rocks and mulch do not qualify as vegetative cover pursuant to this rule. These standards enables the Division to determine: 1) If the revegetation plan has been followed; 2) If the existing cover is sufficient to provide effective soil stabilization; and, 3) If progress is being made toward the ultimate goal of providing a permanent, diverse, and effective vegetative community. The Division finds that because Sun Coal Company has not submitted technical data with reference to successful establishment of revegetation (based on the cover standards of Rule 4.15.8) and has not documented revegetation methodology, it has not satisfied a minimum requirement for Phase II Bond Release. In addition, field inspections have noted the existence of substantial gullying on the backfilled area, indicating that an effective stand of vegetation has not been reestablished. Sus ended Solids Determination - The Division required Sun Coal Company to submit tec nica ata w is emonstrates that levels of suspended solids contributed to streamflow or runoff outside the permit area are comparable to the pre-mining condition. During the period of this review, the Division has been examining the policy for the Phase II bond release suspended solids determination. The policy, which is nearly completed, will allow the operator to compare suspended solids measurements from sediment control structure outlets to undisturbed or pre-mine data in order to meet the requirements of Phase II. Pond inflow data or direct slope erosion measurements would be required only for pond removal, but could also be used to meet Phase II requirements. Without the benefit of this policy, Sun Coal Company has submitted calculations using the Modified Universal Soil Loss Equation (MUSLE) to demonstrate that the sediment yield on the backfilled area meets the Phase II criteria. This type of demonstration would meet the more stringent requirements for pond removal. The applicability of this equation on reclaimed lands in the Western United States is somewhat questionable, and is the subject of continuing scientific research. For this reason the equation must be used conservatively and reviewed carefully. After completing its review of the submittal, the Division rejects the demonstration for the following reasons: 1. The soil erodability factor (K) is the same for disturbed and undisturbed land. Division calculations using the soil erodability nomograph, and soil compaction data supplied in the permit application, indicate that this factor should differ between the pre-mine versus post-mine conditions.