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L i ' September 28, 1998 B. Use excavated soil and rock material for constructing the compacted embankments for the tailings pond having a maximum particle size of 6 inches, and containing no ' wood fragments, metal, wire or other waste debris or deleterious materials. 2.4 BEDDING MATERIAL ' A. Granular bedding materials for pipes and structures shall be swell-graded gravelly sand, having a maximum particle size of 1-inch and not more than 5 percent, by ' weight, of the material passing the No. 200 sieve. B. Bedding material under the tailing pond liner system may be a uniform sandy ' material. Material obtained from the tailings pond excavation may possibly be used for bedding. The use of tailings as bedding material is acceptable, if the material classifies as a sand and suitable moisture is present. If the tailings has a clay ' particle content grater than 15%, the use of tailing for the purposes of bedding will not be permitted. If the tailing is saturated, adequate drying shall occur prior to placement as a construction material. 2.5 GEOTEXTILE AND GEOGRID MATERIALS A. Geotextile for use in diversion/sediment control structures shall be a non-woven ' polyester or polypropylene material having a weight of 6, 8 or 10 ounces per square yard as shown on the Drawings, and a flow rate of at least 80 gallons/minute/square foot when tested in accordance with ASTM D4491. If only one geotextile size is ' used throughout the project use a 10 oz/sy, non-woven geotextile having the flow rate specified above. ' B. Geotextile for silt fences shall be woven polypropylene material having a UV resistance of at least 90 percent when tested in accordance with ASTM D4355, and shall have slats for stability during windy periods. ' C. Geotextile for use as a cushion layer underneath geomembrane in the pond shall be as specified in Section 02770. ' D. Geotextile for use as subgrade support over soft soils or tailings shall be a woven polypropylene or polyester, Mirafi 700X, Stabilenka 2400, Contech C300, Nicolon HS600, or approved equal. These geotextiles should be used with at least 2 feet ' of granular borrow soil over the top, or as needed for equipment support. E. As an alternative to woven geotextiles for subgrade support, polypropylene geogrids may be used, Tensar (Contech) 6X1100 (BR1), Nicolon/Mirafi MX1, or approved equal. These geogrids should be used with at least 1 foot of granular borrow soil over the top, or as needed for equipment support. ' 2.6 EROSION CONTROL MATERIAL ' Earthwork ' J:~Sa6115PEC5FNL.WPD 02200-5