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INTRODUCTION <br />The original (proposed) location for Pond 005 was submitted to CMLRD on November 9, 1990 <br />as part of Permit Revision No. 1. Subsequently, in a memo dated May 23, 1991 from Bruce <br />Stover to Larry Rou[ten, a number of concerns were raised regarding land stability in the <br />north mining block. These concerns prompted CMLRD to issue approval of PR Yf1 with certain <br />stipulations. In brief, Stipulation No. 17 required Peabody to revise its design, <br />complete land form mapping, and include plans for geo[echnical monitoring. Please see <br />Proposed Decision and Findings of Compliance for the Seneca II-V Mine, Permit C-62-O57, <br />Permit Revision No. 1, September 4, 1991 for complete discussion regarding the <br />stipulation. <br />That stipulation prompted Peabody to contract the services of John Ivey of Amuedo and <br />Ivey, Inc. to map and investigate the landforms near the proposed facilities, and Dick <br />Suedkamp of Ground Engineering Consultants, lnc. to investigate the geo[echnicaL stability <br />of the area and assist in the embankment design. These reports can be found in <br />Attachments 13-3A and 13-38. Peabody conducted the hydrology and sedimentol ogy portions <br />of the pond design. This information can be found in Attachment 13-3. As a result of <br />• these investigations, the final location for Pond 005 is shown on Exhibit 13-2 and <br />described as located in the NV1/45V 1/4 of Section 10, Township 5 North, Range 88 Vest in a <br />tributary to Dry Creek (referred to in some sections of the report as Pond 005 Gulch). <br />Sediment Pond 005 was designed in accordance with the criteria set forth in 4.05.6. The <br />primary function of the pond is to control sediment from [he mine disturbance area. <br />Surface runoff not requiring treatment is diverted around the pond. According to the <br />definition of a sedimentation pond (1.04(115)), this structure does not meet either the <br />State Engineers requirements or [hose set forth by MSHA. <br />The embankment for Pond 005 was designed in accordance with 4.05.6(11). Due to the <br />saturated condition of the foundation at least part of the year, the embankment was <br />designed with a horizontal drainage system. A toe drain will collect the water and <br />discharge it below the toe of the embankment. This system is designed to act as <br />controlled seepage through [he embankment. <br />The proposed pond and embankment will be constructed to the prescribed standards for a <br />• permanent impoundment structure. The primary purpose of the structure as mentioned <br />previously will be [o control runoff and sediment from a watershed disturbed by proposed <br />13-3-1 Revised 03/13/92 <br />