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spillway locations only. This revision will provide an erosion resistant alternative to the 3:1 sand and gravel <br /> interior slopes and allow the gravel resource to be maximized. During the flood event in 2023, Pond 1 was <br /> largely undamaged therefore demonstrating this design is effective in mitigating flood damage. <br /> The proposed revisions to the Mining Plan, Reclamation Plan and design details for the slope liner are included in the <br /> attachments of this TR-09 document. Testing of the clay materials available for use in reclaiming the mine slopes <br /> determined that the natural claystone is the weakest material proposed for use in the reclaimed slope which resulted in a <br /> final recommended slope of 4:1. The slope stability and geotechnical analysis are included in Attachment A and <br /> Attachment B includes the technical specifications for constructing the compacted clay reclamation slope. The factors of <br /> safety meet or exceed design standards for these facilities. <br /> Conclusion <br /> The design presented includes the repair of recent flood damage and incorporates several measures to reduce the <br /> likelihood of damage or failure during flooding conditions. The protective measures include: <br /> Pond 3 Flood Repair: The damaged slurry wall is proposed to be repaired by constructing a compacted clay <br /> liner that ties into the undamaged slurry wall. The surrounding side slopes are to be mined at a 1:1 slope and <br /> reclaimed with clay material borrowed from the reservoir bottom. The design plans can be found in Attachment <br /> B. <br /> y Pond 2 Interior Reclamation Slope: Pond 2 will be mined at a 1:1 slope and reclaimed at a 4:1 slope with clay <br /> (overburden, mud seams and/or weathered bedrock) material that is more resistant to erosion during flooding <br /> events.The design plans can be found in Attachment B. <br /> Bonding: <br /> The new reclamation plan includes a 4:1 finished slope (Ponds 2 & 3) using compacted clay material which will reduce <br /> the risk of major damage during flood events and therefore does reduce risk, however no bonding reductions are <br /> proposed as part of this submittal. <br /> We appreciate your review. Should you have any questions, please contact us. <br /> Sincerely, <br /> CIVIL RESOURCES, LLC. <br /> Brad L. Hagen, P.E. <br /> Principal Civil Engineer <br /> Cc: Mr. Joe Lamanna, Brannan;Alex Schatz, Brannan <br /> Attachments: <br /> DRMS Figures (Mine Plan and Reclamation Plan) <br /> Attachment A—Reclamation Slope Stability Analysis <br /> Attachment B—Reclamation Slope Technical Specifications <br /> J:\Brannan\Holton\DRMS\TR09-Nov2025\TR09-txt.doc <br />