2021-09-09_REVISION - M2004044 (10)

Home Browse Search

Disturb Mining Operation ed Area (acres) Active Mining Area: 1. Backfill remaining East Cell mining face and side slopes (2,300 feet in length averaging 27 feet deep requiring backfill and rough grading to 3H:1V slopes.) 2. Rough Grade remaining disturbed areas of the east cell 3. Replace topsoil on backfilled area of East cell above the HWL of the reservoir (61.5 acres) 4. Final Grade East Cell Miscellaneous Disturbed Areas (Stockpiles, Haul Roads, Conveyor route) 1. Replace topsoil on internal haul roads and main site entrance (3 acres x 0.5') 2. Replace topsoil on conveyor route (11.5 acres X 0.5') 3. Replace topsoil on stockpile area (5 acres x 0.5') 4. Scarify internal haul roads and conveyor route areas 5. Final grade all miscellaneous areas (8.3 acres x 0.5') 6. Reseed 20% of all areas in the area of disturbance above Final Reclamation: 1. Seeding — entire East Area above the highwater line of the reservoir plus internal haul route and the conveyor route. 2. Weed management and re-seeding (20% of the Affected Lands located above the hi hwater line of the reservoirs) Total Disturbed Area 83.8 Diversions and Impoundments Roads and irrigation ditches will effectively minimize stormwater surface run-on to the mining site, so run-on diversion structures are not anticipated. During the initial mining activities, stockpiling of topsoil and overburden on the surface is anticipated. Diversionary channels, as shown on Exhibit C, will be used divert surface runoff from leaving each of the Areas or entering the wetlands areas. Surface diversion channels will convey runoff to settling ponds, prior to discharging to the South Platte River. As mining progresses and the excavation increases in size, diversionary channels will convey less runoff because more runoff will enter the mine excavations. Runoff that collects in the excavations will be conveyed by the dewatering trenches to a common point, where it will be pumped to the river after sediment settling has occurred, if necessary. Aggregate Industries—Tucson South Amendment—MLRB 112 Permit Application Exhibit D-8