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As mining progresses and prior to stripping soil and overburden, vegetation (trees and brush)will be cleared
<br /> and grubbed. Trees will be harvested for lumber,firewood, and other uses. Brush and branches will be shredded or
<br /> chipped and stored with soil for additional biological material for reclamation and to protect stored soil. Some may be
<br /> hauled off-site for beneficial use or burned under controlled conditions,for disposal. Similar materials from off-site may
<br /> be stored and used as part of reclamation or ranch activities or processed for sale and use off-site. Livestock manure
<br /> may also be present or brought on-site and incorporated into reclamation.
<br /> Generally, this plan assumes that the site averages 3 feet of soil and overburden, with an average depth of
<br /> mineable material of 20 feet. (In later phases, the average depth is anticipated to be less, due to deposit conditions
<br /> and need to establish a sustainable post-reclamation terrain.)Therefore,each acre excavated can provide up to 4,840
<br /> CY of soil/overburden (1/12 soil, or 403 CY) and 32,267 CY of pit run material. It is assumed that processing pitrun
<br /> will produce 90%construction materials, up to 29,040 CY(36,300 T)per year for each acre mined,of which about 1%
<br /> will be consumed on-site. Therefore,to ship up to 72,000 Tons will require a minimum of 2.0 acres to be stripped and
<br /> excavated each year.(Larger areas will be required around the perimeter,to provide for suitable slopes in reclamation,
<br /> Processing materials will generate an additional 3,227 CY of fines/reject material to be used together with 4,437 CY
<br /> overburden for backfill and slope stabilization/reduction following excavation. Due to uncertainty regarding quality and
<br /> quantity of the in-place material, it is assumed that about five acres will be affected each year,which is shown on maps
<br /> in Exhibit C.
<br /> Mining of the site will be done in an estimated 10 to 20-year period, in four phases:
<br /> Phase 1:28.9 acres,starting with the currently disturbed area and moving south around the reclaimed USFS
<br /> mining area along the east side of Oakbrush Hill,and(if sufficient recoverable material exists in the old USFS pit area),
<br /> that area itself, continuing to the south edge of the permit area. Reclamation will be done one to two years behind
<br /> excavation, except for temporary internal haul roads and necessary perimeter storm water controls(see Exhibit F-1).
<br /> Most soil and overburden will be placed on the downhill side of the area being mined in storage berms that also provide
<br /> storm water control. Some material may be placed on the crest of Oakbrush Hill (uphill side of area being mined)for
<br /> ease of reclamation. See Exhibit E for details regarding possible expansion of affected area (to the west) as needed
<br /> for reclamation. Due to the need to provide satisfactory slopes (see reclamation plan, Exhibits E and F), mining is
<br /> assumed to disturb an average of five acres per year; previously mined areas are also expected to require more area
<br /> disturbed to provide needed material. Therefore, Phase 1 is estimated at 6 years.
<br /> Phase 2: 39.7 acres,following mining (with concurrent reclamation) and with landowner permission, mining
<br /> will then be done to the northeast of the Plant Area, on North Oakbrush Hill,to near the north edge of the permit area,
<br /> similar to the procedure for Phase I but modified due to the different shape of North Oakbrush Hill deposits.Assuming
<br /> the same factors as for Phase 1, Phase 2 is estimated at 8 years(Operation years 7-14).The existing trail/ranch road
<br /> along the southwest area of this Phase will be improved and used for hauling.
<br /> Phase 3: 14.9 acres, based on the time frame, demand, and material quantity, mining may then continue to
<br /> the east-southeast of the South Area,working from west(previously mined areas)to east,with mining at an increasingly
<br /> shallow depth to blend smoothly with unaffected ground approximately 50 to 100 feet inside the permit boundary.This
<br /> phase, due to terrain, will require more area to be mined each year, so Phase 3 is estimated at 2-3 years(Operation
<br /> years 15-17).There will be no disturbance of a 200-foot buffer zone between mining and the adjacent property.
<br /> Phase 4: 21.1 acres, similar to Phase 3, southeast of the North Area. Based on the same assumptions as
<br /> Phase 3, and limited by County willingness to allow mining beyond 20 years, Phase 4 is estimated at 3-4 years, if
<br /> permitted by Archuleta County(Operation years 18-20+.).
<br /> Closing phase: 14.5 acres,at the end of one or more phases,the operator may mine two small areas on the
<br /> crest of the Oakbrush Hills, including up to 8A acres West of Phase 1 and up to 6.1 acres West of Phase 2. This will
<br /> produce some material for processing and transport off-site, material to be used on Dutton Ranch internally, and
<br /> material necessary to achieve acceptable reclaimed slopes.This phase may be done concurrently with other phases
<br /> and is not to take more than 1 year beyond the end of Phase 3 or 4, but may be concurrent.Depth will vary significantly
<br /> but is expected to have less than 10 feet below natural ground surface.
<br /> Total all phases: 132.3 acres, including 120.7 acres newly affected for excavation.
<br /> C&J Gravel Products, Inc. Page 13 of 93 20 OCT 2021
<br /> Application for Permit: Oakbrush Hill Gravel M-2021- C&J-DPR-V5-001
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