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Stoner E_ngineering & 5urveying <br /> Engineering, Testing & Surveying <br /> Date: January 28, 2014 <br /> To: Tom Bird <br /> Manager, Coal Services <br /> GCC Energy, LLC <br /> 6473 County Road 120 <br /> Hesperus, CO 81326 <br /> (970) 385-4528 <br /> From: Ryan Griglak, P.E.XA/— <br /> Project Manager <br /> Stoner Engineering & Surveying <br /> Re: King Coal II -Annual Water Quality Improvements Inspection (Amended) <br /> On September 29, 2013, Ryan Griglak, P.E. visited the GCC Energy, LLC King Coal II site to <br /> conduct the annual inspection of the water quality pond installed to prevent contaminated <br /> storm water runoff from escaping the site in events smaller than the 100-year storm event. <br /> There were approximately 8-inches of water (Surface El. = 7226.9) in the water quality pond at <br /> the time of the inspection. The elevation at the bottom of the pond was determined to be at <br /> an elevation of 7226.2. Based upon this elevation, the pond can collect an additional three (3) <br /> feet of sediment before reaching the 60% cleanout level (El. = 7229.25). The current sediment <br /> level in the detention pond represents roughly 6% of the allowable 1.57 [ac-ft] of sediment <br /> which is the 60% cleanout level as shown in the Sediment Pond Stage Discharge Curve prepared <br /> by EIS Environmental & Engineering Consulting dated 12/18/08. <br /> The vegetation established both inside and out of the pond is well established to minimize the <br /> erosion impacts of storm runoff. The outlet structure shows no signs of damage and was <br /> functioning as designed at the time of the inspection (see Pic. 1). The east pond inlet pipe <br /> erosion has been repaired with a geo-textile fabric overlain with riprap to armor the <br /> embankment which is functioning as designed (see Pic. 2). The water quality pond appears to <br /> be in generally good condition. There were no signs of weakness or distress to either the outlet <br /> structure or the embankment material. The water quality pond has the storage capacity to <br /> function as designed. <br /> P.O. Box 1163 28 South Washington Street Cortez, Colorado 81321 <br /> 970.565.7483 stonerenaineer@frontier.net 970.565.7704 <br />