PERMFILE67901 - Laserfiche WebLink

Home Browse Search

u Revivon p I -Page 6 of 30 During the mining and reclamation process, all precipitation within the project site will be collected and remain on the project site. A drainage Swale will be installed along the north. west and south property lines, which will collect and divert surface Flows into a new retention pond located along the west property line. The retention pond has been sized in accordance with the City of Grand Junction standards. Mining for the sand and gravel, and for a portion of the backfill operations, will require dewa[ering. A pump will be used to dewater the excavation pit area and discharge into a new settlement pond constructed near the northwest comer of petmit area. The settlement pond will allow the sediment to drop out of the water before it is discharged offsite into the Canning Factory Ditch. The side slopes for the pond shall be constructed at a 3H:1 V, and all overburden removed for the pond construction shall be stockpiled around the pond perimeter. (d) The si.e ojareas to be worked at am one time; Mining at the site will be progressive across the permit area, as discussed in pan (a) above. The excavated pit azea (backfill placement area, sand and gravel highwall, and overburden highwall) will be no more than three acres in size at any one time. The three-acre area has been established to limit the amount of imported reclamation fill requtred to reclaim the site to approximately 75,000 cubic yards. (e) An approximate timetable to describe the mining operation. The timetable is for the purposes of establishing relationship between mining and reclamation during the diJjerent phases ojthe mining operations. An Operator shall not be required to meet specific dates jot initiation, or comp/etion of mining in a phase as may be identified in [he timetable. This does not exempt an operator from complying with the performance standards stated of Section 3. /. Such timetable shall include: • .9n estimate ojthe periods ojtime which wit! be required for the various stages ojthe operation; • A description of the si.e and location of each area to be worked during each phase,, and • Outlining the seq:tence in which each stage or phase ojthe operation will be carried out Mining for the sand and gravel will be progressive across the site, as discussed in part (a) above. As mining operations progress across the permit area, backfilling operations will be following behind the active sand and gravel highwall. The excavated pit area will be limited in size to no more than three acres in size at any one time. Once backfill has reached the site reclamation plan elevations, the azea will be ready for preparing the area for seeding. To make the reclamation cost effective, the operator proposes to delay topsoiling, mulching, seeding and fertilizing until there is a maximum often acres to work, and the timing is such that planting can occur in the early spring or late summer months. The operator estimates it will requre around three years of mining operations before 10 acres will be ready for seeding. Also discussed above, the topsoil will be stripped from areas before surface disturbance activities occur. The maximum area for topsoil stripping shall be 10 acres. Nature, depth, and thickness ojthe deposit to be mined and the thickness and type ojoverburden to be removed; and Nature of the stratum immediately beneath the material to be mined in sedimentary deposits. Overburden material within the project site is approximately 12 feet deep. According to the US Department of Agriculture, Department of Natural Resource Conservation Service (MRCS), the overburden soil consists of a silty clay loam [hat is no[ suited for cultivation due to high salinity levels. Vegetation on the project site consists of tamerisk, greasewood, and halogeton. These plants are listed on the State of Colorado's noxious weed list. The top two to six inches of existing topsoil material will be stockpiled and reused for site reclamation work.