PERMFILE113437 - Laserfiche WebLink

Home Browse Search

Stipulation No. 4 -13- WITH RESPECT TO THAT PORTION OF THE LOAL LOAD-OUT LOCATED WEST OF THE COUNTY ROAD 79 IDENTIFIED AS AN ALLUVIAL YALLEY FLOOR, WITHIN TWO YEARS AFTER THE COMMENCEhJENT OF THE PERIOD OF EXTENDED LIABILITY AS SPECIFIED IN RULE 4.15.1(5) THE OPERATOR SHALL COMPARE THE SOIL CHARACTERISTICS OF THE RECLAIMED AREA WITH AN ADJACENT UNDISTURBED AREA. THIS COMPARISON SHALL BE SUFFICIENT TO VERIFY THAT THE INFILTRATION, PERMEABILITY, ANO TEXTURAL CHARACTERISTICS OF THE RECLAIMED SOILS HAVE BEEN RE-ESTABLISHED SUFFICIENTLY TO RENDER THE AREA AS POTENTIALLY FL000 IRRIGABLE. The results of the applicants AYF study at the mine reveals. with one exception, no streams that meet the geomorphic criteria for alluvial valley floors. The applicant and Division field checked the study results. Streams within the study area, with one exception did not contain sufficient alluvial bodies to qualify as alluvial valley floors. Newlin Creek however, was found contain sufficient alluvial deposits and was investigated further. The Newlin Creek valley bottom is associated with the perennial stream of Newlin Creek which flaws to the northeast across the permit area. The alluvial valley of Newlin Creek is assumed to be the area delineated in the permit application on Map Dor-K-Y as being riparian woodland. The Newlin Creek valley floor ranges from 150 to 500 feet wide and is cut into the pediment surfaces each side of the valley to a depth of 20 - 30 feet. The • stream channel has Bisected the valley bottom which, in portions, isolates the alluvial bodies. The Newlin Creek valley is mapped as supporting a riparian community. However, a field examination of the valley bottom reveals only sparse vegetation indicative of subirrigation dependancy. An examination of the stream channel that was excavated by the G.E.C. "prospect pit' downstream on Newlin Creek did not identify seepage either from alluvial fill or the adjacent pediment deposits. This indicates that water is not available for subirrigation purposes on a significant scale. These facts would rule out the possibility of this valley being agrlculturalty useful through subirrigation. The potential for flood irrigation of the Newlin Creek Valley was also investigated. The are no known current or historic flood irrigation areas on Newlin Creek. And although regional data is sparse, it does not appear that flood irrigation is practiced on similar valleys at the elevation of the mine. The Newlin Creek Valley at the mine does not have the potential to be developed for flood irrigation in the future. There are no extensive soils developed on the alluvial valley bottom. The alluvium consists of gravel, cobbles, and boulders in a silty sand matrix which are not suitable for agricultural use. One final obsticle for flood irrigation is the lack of surface water flow. As was mentioned earlier, the town of Florence diverts the stream flow above the mine for use by the city. This results in almost no stream flow for much of the year.