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-14- Colorado River A large area (all or portions of six sections) of unconsolidated streamlaid deposits has been identified within 2 1/2 miles of the southern boundary of the permit area, to the north of the Colorado River. The origin of the deposits (fan or terrace) is not identified by the applicant. However, the applicant has concluded that, due to widespread flood irrigation on the deposits, the entire area is a probable alluvial valley floor. Irrigation water is stored in Grass Valley Reservoir and conveyed to a system of ditches on the AVF via Harvey Gap Drainage. More detailed geologic and certain areas from AVF information indicating the existing flood irrigation, unconsolidated stream laid shown on Figure 1 of the floor. West Elk Creek irrigation information could potentially exclude designation. However, based on the available presence of unconsolidated streamlaid deposits and the Division concludes that all areas designated deposits to the south of the permit boundary as permit application constitute an alluvial valley Portions of the West Elk Creek Valley approximately 1 1/2 miles to the northeast of the permit boundary have been delineated as a probable alluvial valley floor by the applicant, based on the presence of unconsolidated streamlaid deposits and flood irrigation. However, no determination will be made by the Division at this time, since West Elk Creek is not hydrologically connected to the proposed permit area and there is no potential for impact to the probable AVF as a result of the proposed mining operation. All surface water from the permit area drains into Harvey Gap. Strata of the Isles formation outcrop several hundred feet topographically above the alluvial deposits of West Elk Creek and ground water movement is downdip to the southwest. Thus, there is no ground water or surface water communication between the proposed permit area and the alluvium of West Elk Creek. Alluvial Valley Floor Findings Pursuant to Rule 2.06.8, the Division is required to make specific written findings on the effect of mining on all AVF's within the permit and adjacent area. The required findings for the Colorado River AVF adjacent to the permit area are presented below. The ro osed minin o eration5 would not interru t, discontinue, or rec ude farmin on the a uvia va e f oor. The surface faci ides associated with the mine are ocated approximately one half mile from the designated alluvial valley floor. No portion of the alluvial valley floor would be undermined by the proposed operation. The southern permit boundary is approximately 1/2 mile north of the northern limit of the alluvial valley floor.