2009-08-25_PERMIT FILE - M2009062

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EXHIBIT E - Reclamation Plan 1) The Pierce North gravel pit is proposed to be reclaimed as an on-line stormwater detention and flood control structure to be maintained by Weld County. The reclamation final grading will create an on-line detention pond which will reduce flooding risk on County residents along Lone Tree Creek downstream of the gravel pit site. The detention pond created during and after mining will be below existing grade; therefore rip-rapped runoff inlets and a rip-rapped outlet spillway will be needed to convey runoff into and out of the pit. The Pierce North gravel pit will not intersect groundwater - this will be a dry pit. It is anticipated that no permanent pool ponds will be constructed or remain on site; any runoff entering the pit will infiltrate to groundwater through the base and walls of the pit. 2) a) Site reclamation will be sequential as mined areas are re-graded to stable slopes and re-vegetated. Reclaimed slopes will be graded at a maximum of three to one (3:1) horizontal to vertical. Since the pit and stockpiles may be active for ten years or more, the location of sand and gravel excavation, crushing, and stockpiling areas at the Pierce North site will move around within the below grade pit. Topsoil stockpiled at the site will be utilized for reclamation following cessation of gravel excavation / mining. The Pierce North gravel pit will not intersect groundwater - this will be a dry pit. See Exhibit F. b) Reclaimed slopes will be graded at a maximum of three to one (3:1) horizontal to vertical and re- vegetated in accordance with NRCS and County weed management guidelines. Surrounding land use is primarily dry land agriculture. One-half mile to the south is the `old' Pierce pit, also county-operated and now reclaimed. Re- vegetation has occurred and is under County maintenance. C) The reclamation plan will be implemented in stages. Following each mining season's activities, regarding an stabilization of completed areas will be accomplished by Weld County Public Works. Reclaimed areas will be stabilized by: i) Concurrent regrading on areas of the site where excavation has been completed. ii) Replacement of topsoil in thicknesses equal to or exceeding the original topsoil depths found at the site. iii) Soil amendments, seed mix, and application rate to be determined in accordance with NRCS guidelines and Weld County Weed Control requirements. iv) Local conditions at the Pierce North site dictate a drought-tolerant native species seed mix appropriate for non-irrigated pasture. iv) Seed mix and application rate to be determined in accordance with NRCS guidelines and Weld County Weed Control requirements (see below). v) Depending on ambient conditions, the application method may be hand broadcast, hydroseeder, or drill and crimp. vi) Per NRCS guidance, permanent seed cover will be placed in November on final graded areas. vii) Mulch application may be concurrent with seeding (hydroseeding or drill and crimp). Mulch may include straw and tackifier. d) The mining plan includes stripping of topsoil from the area to be mined. This topsoil will be segregated from other overburden and stockpiled for use in reclamation (see mining plan Exhibit D). Preliminary Pierce North Pit Soil, Fertilizer, Mulch, and Re-Seed Plan Seed mix: Buffalo Grass (Texoka, Sharps Improved) applied at 4.5 lbs/acre, Little Bluestem ) applied at 3.5 lbs/acre, Sideoats Grama (Vaughn, Butte, Niner, El Reno, and Haskell) ) applied at 2 lbs/acre, Blue Grama (Hachital, Lovington) ) applied at 4.5 lbs/acre, Sand Dropseed ) applied at 0.5 lbs/acre, Total: 15 lbs pls/acre. Other addition: MADAVE B\Pierce North\DMG permiAExhibits-Revl.doc 8/21/2009