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EXHIBIT E <br />JVA, Incorporated <br />P.O. Box 1860 <br />Winter Park, CO 80482 <br />Ph: 970.722.7677 <br />Fax: 970.722.7679 <br />Toll Free: 877.444.1951 <br />January 20, 2010 <br />Mr. Ted Pratt <br />Flintstone Gravel and Trucking, Inc. <br />P.O. Box 950 <br />Granby, Colorado 80446 <br />Reference: Pickering Family Pit SWMP <br />Stormwater Clarification Letter <br />JVA JN 1657c <br />Dear Mr. Pratt: <br />Web site: <br />www.jvajva.com <br />E-mail: <br />info@jvajva.com <br />This letter is intended to serve as clarification to our basis of design for the proposed SWMP for the <br />Pickering Family Pit, based on our discussions on January 14, 2010. It is our understanding that the <br />MLRB review raised questions concerning the design of the sediment pond as shown with the <br />SWMP for the project. <br />It should be noted that the following reports/letters were utilized in preparation of the SWMP for this <br />project: <br />• USDA NRCS Soils, Vegetation and Reclamation Report, dated November 13, 2009, <br />prepared by Mark Volt, District Conservationist, NRCS. <br />• PCN-NWP#14, Pratt Property, dated November 4, 2009, prepared by David Blauch, Senior <br />Ecologist, Ecological Resource Consultants, Inc. <br />The sediment basin proposed for this project is designed to provide a minimum volume of 1800 CF <br />per disturbed Acre, or 27,000 CF, per Grand County and NWCOG recommendations. A minimum <br />excavated bottom area of approximately 2,050 SF, with 3:1 maximum side slopes yields a volume of <br />approximately 31,500 CF at a depth of approximately 7.8 feet. A 12" PVC riser pipe with 6 <br />columns and 5 rows of 1.25" diameter perforations will provide controlled release, allowing <br />sediment laden stormwater time to deposit excess sediment within the basin. An emergency <br />overflow weir is proposed to convey an anticipated 100-year event, or 10.50 CFS, calculated <br />utilizing the rational method for the disturbed area, according to Grand County regulations. This <br />weir and associated rundown is designed using the Manning's formula with a 6" maximum depth <br />and a 14' crest length, and protected from erosion with 00=9" riprap. <br />Please contact me with <br />Sincerely <br />JVA, I4j <br />By: <br />KPVFdg Vecchiarelli, LEED AP <br />Associate <br />BOULDER <br />questions, comments or concerns. <br />FORT COLLINS <br />WINTER PARK