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Mountain Coal Company Exhibit 69 <br /> West Elk Mine Sylvester Gulch Facilities <br /> • INTRODUCTION <br /> In 1998, Mountain Coal Company(MCC) constructed new mine dewatering and treatment <br /> facilities at the site of existing dewatering boreholes within the Sylvester Gulch Facilities Area <br /> (SGFA) (Drawing Sheet Cl). These facilities provided a method of reducing total suspended <br /> solids (TSS) in mine water prior to discharging to the West Fork of Sylvester Gulch in <br /> compliance with NPDES discharge permit requirements. The installed facilities include a <br /> Dewatering Pump Station and Treatment Building and a Finishing Pond (Pond 017). A current <br /> plan view of the existing Sylvester Gulch mine water system is shown on the attached Drawing <br /> Sheet C2. <br /> Several other facilities were originally planned but not constructed, including a Presedimentation <br /> Basin, Decant Return Basin and Pump Station, and Sludge Drying Lagoons. The Dewatering <br /> Pump Station and Treatment Building was originally constructed to also house several pieces of <br /> treatment equipment(flocculation and sedimentation units, chemical Seed equipment, and <br /> chemical storage units) that were not installed or necessary given the fact that the facilities listed <br /> above were not constructed. These additional facilities and treatment equipment may be installed <br /> at a later date, if deemed necessary. <br /> In January 2007 a new limit for total recoverable iron(Fe) of 1,000 µg/1 went into effect per the <br /> • NPDES discharge permit. This exhibit describes the plan for an expansion of the SGFA to <br /> provide additional treatment redundancy, efficiency, and operational flexibility to facilitate <br /> compliance with NPDES discharge standards for TSS and total recoverable Fe. The treatment <br /> system design is flexible to allow for the use of various components as necessary to enhance <br /> treatment. <br /> Preliminary design drawings and a flow diagram for the proposed treatment system are also <br /> included on Drawing Sheets Cl —C6 and PFl. Pond area reclamation topography is illustrated <br /> on Drawing Sheet R1. A full set of construction drawings and technical specifications will be <br /> developed for construction of the treatment system, as will an Operations and Maintenance <br /> (O&M)Plan. <br /> FACILITIES DESCRIPTION <br /> Provided below is an overview of the system modifications and design parameters,planned <br /> retrofits to the existing SGFA, design of a second settling pond, description of the treatment <br /> process, and storin water control measures. <br /> System Overview <br /> Mine water will continue to be extracted from the existing dewatering boreholes and mine water <br /> • sump. The surface system is designed to actively aerate and increase the dissolved oxygen <br /> 2 <br /> Rev.10/97-TR83,Rev.04/09-TR116 <br />