2025-10-07_REVISION - C1982057 (16)

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Permit Number: C1982057 Page 9 of 20 Phase III five years for monitoring sites downstream of WSH7 (outfalls 017 and 016) and stream point WSD5 as presented in the permit document and past annual hydrology reports. Phase I Bond Release Phase I release areas comprised of roads, ponds and areas around ponds 006, 016. All impoundments were inspected during the 5 June 2025 bond release inspection. Multiple Exhibits in Tab 13 of the permit include designs and as-built plans for each impoundment and any necessary impoundment certifications. During the bond release inspection, the Division inspected the general configuration of each impoundment to determine if they have been constructed in accordance with the approved permit. Also, the embankments were inspected for signs of erosion, weaknesses and failures. Previous measurements taken by the Division of primary and emergency spillway structures determined that construction was in accordance with the approved plan and permit requirements. All impoundments were functioning as designed at the time of inspection. Phase II Bond Release Phase II release areas comprised of roads, ponds and areas around ponds 006, 016 and the slide area above Pond 015. A sedimentology demonstration and vegetative cover analysis were provided for these areas in the application. Topsoil depth replacement information was included in the SL5 Phase II bond release application that was approved in 2014. In accordance with Rule 3.03.1(3)(b) and Section III.A.7.a, of the Division's 1995 Guideline Regarding Selected Coal Mine Bond Release Issues, SPL provided a suspended solids evaluation. Appendix E Table 6 of the SL8 application provides a statistical summary of the pre‐mine and post mine total suspended solids (TSS) for the Dry Creek and the Sage Creek watersheds. In both watersheds the pre-mine (Apr 1987 - Sept 1989) values were higher than the post mine values (Jan 2019 - Dec 2023) at all stream monitoring points with the exception of WSH9 where pre-mine values were lower. Stream monitoring point WSH9 is located upstream of all the outfalls within the Dry Creek watershed, and sampling at this location was not initiated prior to mining in the watershed. The downstream outfalls receiving runoff from areas associated with WSH9 exhibited lower than predicted values indicating that TSS values at WSH9 are impacted by watershed activities related to processes other than the SPL mine. Phase II cover success was evaluated for the parcels depicted in the adjacent map. Vegetation sampling was conducted by Cedar Creek Associates in 2022 and 2023 and sampling results comprise Attachment D, Revegetation Success Supporting Documentation of the application. Vegetative cover success is based on the allowable all hit herbaceous cover. Vegetative cover success on the reclaimed area will be no less than 90% of the cover success standard with a 90%