2009-08-19_REVISION - M1987049 - Laserfiche WebLink

Home Browse Search

7. "Please explain how the topsoil and overburden stockpiles will be configured to reduce erosion. " Applicant's Response: Typically, topsoil and overburden stockpiles have an elongated rectangular shape with side slopes that vary anywhere from 1.5: 1 to 2:1. Initial topsoil and overburden stockpiles generated from the new mining area will in place less than a year. Stockpiled material will be used for reclamation as soon as enough sand and gravel have been excavated to allow reclamation to begin. This approach will facilitate concurrent mining and reclamation where topsoil and overburden stripped from areas to be mined will directly placed in the previously mined area thereby allowing the operator to handle the material only once and keep stockpiles to a minimum. The operator will stockpile a limited amount of topsoil along the west side of Brighton Road in order to establish a temporary screening berm during the life of this stage of mining. In order to reduce erosion, long term topsoil and overburden stockpiles (those in place more than one year) will be vegetated with the following grass seed mix: SEED NUX FOR TOPSOIL STOCKPILE PROTECTION Scientific Name T Common Name Variety' Seeding Rate PLS lb/ac ) PERENNIAL GRASSES Agropyron dasystachyum Thickspike Wheatgrass Critana 4 Agropyron smithii Western Wheatgrass Arriba or Barton 5 Agropyron trachycaulum Slender Wheatgrass Pryor or Revenue 3 Bouteloua curtipendula Sideoats Grama Vaughn 3 Bouteloua gracilis Blue Grama Hachita or Lovington 2 Sporobolus airoides Alkali Sacaton 1 Schizachyrium scoparium Little Bluestein Blaze 1 ' Availability may dictate the need for variety substitution 2 Pure Live Seed/ pounds per acre; rates shown are for drill seeding; double rates for broadcast 8. "Please commit to not exposing ground water until you have an approved substitute water supply plan and a well permit from the Colorado Division of Water Resources. " 8/19/2009