2018-12-26_REVISION - M2008078 (29)

Home Browse Search

RE: Prowers Aggregate Operators, LLC. — West Farm Pit—Permit No. M-2008-078 112c Permit Amendment Application (Revision No. AM-01) Preliminary Adequacy Review Response 12121118 -13- 40)Response: With respect to the conveyor, PAO has decided not to install a conveyor from the wash plant to the south and it has been removed from the map. PAO will submit a technical revision to the permit including details of the structures if they decide to install any permanent conveyor structures within the permit area. The scale house is a mobile trailer unit that is sitting on temporary concrete blocks. The scale house will be removed via towing it offsite and the temporary concrete blocks will be removed and landfilled. No demolition will be required. The area disturbed by the scale house will be reclaimed by topsoiling and seeding the area. Costs for topsoiling and seeding the scale house area have been included in the bond estimate for reclaiming the area west of the pit entrance road. See the attached reclamation bond estimate calculations. 40) Please be advised, the Division must hold 100% of the costs for slurry wall installation until the operator demonstrates the liner has been approved by the DWR, after which time, the Division must hold a minimum of 20% of the costs for installation. Please demonstrate the bond estimate includes 100% of proposed costs for installing the slurry wall liner in the South Mining Area (minus the northern wall to be shared with the existing northern enclosure), and a minimum of 20% of costs for installing the two slurry wall enclosures in the North Mining Area. Please be sure the demonstration (evidence of actual costs incurred or bids provided for the projects) includes line item costs. Response: 20% of the construction costs for the 2 slurry walls in the north mining area have been included in the bond estimate. At this time no mining is occurring in the south mining area. This area is only being used to stockpile material. Costs have been included in the bond calculations to scarify, topsoil, and reseed the disturbed areas in the south mining area. PAO commits to providing 100% of the cost to construct the slurry wall in the south mining area prior to mining below the static groundwater table elevation in the area, or will construct and obtain approval from the DWR for the slurry wall prior to mining below the static groundwater table elevation in this area and provide a bond equal to 20% of the cost to construct the wall until the reclamation of the south mining area is completed. PAO commits to submitting a technical revision including design drawings of the slurry wall prior to constructing it. See the attached revised Exhibit L narrative, reclamation bond estimate calculations, and cost data for the Phase 2 slurry wall construction. 41) Please explain the credits included in the bond estimate for Phases 7 and 10, Phases 5 and 6, Phase 13, Phase 14, Phase 15, Phase 16, and Phase 17. Response: The reclamation bond estimate calculations have been revised. The phased bonding approach has not been used so the credits have been removed because they are no longer relevant. See the attached revised Exhibit L narrative and reclamation bond estimate calculations. 42) The bond estimate includes a lump sum mobilization cost. The Division requires additional information in order to calculate the mobilization/demobilization costs for the proposed reclamation plan. Please specify the type and number of equipment to be used for reclamation, and the nearest location from which this equipment could be obtained. Response: Reclamation is expected to be conducted using the following equipment: • 1- Loader for miscellaneous earthwork • 1- Scraper for moving topsoil V 305 Denver Avenue-Suite D•Fort Lupton CO 80621 •Ph: 303-857-6222•Fax: 303-857-6224