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Mr. Chris Rowe December 12, 2006 Page Four of Eight backfilled and graded to a finished 3:1 slope covered with topsoil and re- vegetated. After the pit has been sealed, it is monitored for a period of 90 days in order to demonstrate that the sealed pit meets the State Engineers performance standazd for lined sand and gravel pits. (See attached is a copy of the criteria for determining compliance with the SEO's guidelines for lining gravel pits). The Applicant does not anticipate any seepage from the clay liner nor from the floor of the excavation. However, in the unlikely event that there is groundwater seepage it is estimated that approximately 11-acre feet or 0.50 feet over the pit floor could seep into the pit without exceeding the SEO's criteria for compliance. It should be noted that above seepage does not take into account any evaporative loss, which the SEO calculates at 2.5 feet per surface acre of exposed water per year. In the unlikely event that water does pond on the pit floor it will do so along the north and northwest side of the pit due to the direction of fall of the pit bedrock. In the event that groundwater seepage causes water to pond on the pit floor, the enclosed seed mix will be used in those azeas that aze too wet to support the dry land seed mix. Once the Camenish Borrow SWP meets the SEO guidelines for lined pits there will be no further augmentation requirements. The SEO guidelines take into consideration precipitation and evaporation when determining if a lined pit meets the SEO's performance standards. 2. There aze a number of DMG permitted sand and gravel pits between Boulder and Fort Collins that have been successfiilly sealed using the same compacted liner method as that proposed for the Camenish Borrow. Most recently, on June 22, 2005 the Division approved Amendment No. Am-1 for the Timnath Pit (Permit No. M-1975-042). The approved amendment changed the reclamation plan from an unlined pond to a clay lined sealed pit. With regard to the Camenish 111 Special Operations Permit Application, the Division is not being asked to approve a reclamation technique that is any different from clay liner applications previously approved by the Division. a. No SEO Requirements. b. Material compaction 95%. c. Topsoil and overburden with + - 2% moisture and 40+ % fines content. d. see enclosed "Typical Liner Section" e. Lift thickness one foot £ Top width 25 feet.