GENERAL48922 - Laserfiche WebLink

Home Browse Search

-:i- The alluvial valley floor would not he physically disrupted b_y mininy. The applicant's discussion of probable hydrologic effects (Section ~.5.3) has identified several effects which may impact the alluvial valley floor in a secondary manner. These effects, discussed above, include the possibility of dewatering the alluvium, and impacting water quality as a result of elevated levels of dissolved solids. Neither potential impact is considered substantial enough in maynitude to warrant changes in the mine plan. Rather, both effects may be addresser) in the monitoring plan, to ensure that essential hydrologic functions are maintained. Monitoring Plan - Findings The monitoring plan provided by the applicant in Section 4.6.3.E wi.l.i meet the objectives of Section 4.14-5 oC the Color:ulo Pe rm,incnt P.oyulntn r~; r''rog r~rm. Oak Creek - Findi 1. The proposed surface coal mining operations mill. not interrupt, discontinue, or preclude farming on the alluvial valley floor. No actual mining will take place 1n the Oni: Creek watershed. several of the mine facilities, however, are 1oc.rted along Oa}; Creek, including the mine offices and loadout facility. Approximateli_; 140 arms of the 4,330 acres to be permitted are sited in the Oak Creek draina ere. i.ll surface disturbance resulting from mining will occur in the Trout Creek watershed. As shoran on Exhibit 4.u-16 of the permit appli- cation, no irrigation activities exist within the Gak Czeek AVF adjacent to the permit area. The land use is undeveloped rangeland and is not siynificant to farming on the AVF. 2. The proposed operations will not materialLj rlamaye the quantity and quality of water in surface and undergrounrl water systcnis that supnlu those alluvial valley floors or portions of a L'uvial t;i1 L^y floors. All waters which drain from the "mi.ning )oval disturbance" portions of the permit area will flow away from Oa Y. Creek and ta.~ords Trout Cr_ek. Therefore, no siynificant alteration of the quantity anc7 quality of ;.~a ter supplied to the OaY. Creek AVF is anticipated. The facilities located in the Oar: Creek drainage will net significantly affect the quantity of water reachiny the channel or the alluvium. Changes in water quality may be possible as a result of the loadout operations; however, the applicant will be controlling runoff from the facilities area through the use of a sedimentation pond. This should minimize deleterous water quality affects to Oak CreeY, to the maximum reasonable extent. Additionally, wat^r quality samples wi L' be obtained throughout the mining and reclamation opera ti n9 to ensure that substantial changes in water quality are not realized. Furthermore, any changes in instream water quality in Oak Creek will exist only during the life-of-the-mine. Following cessation of operations and subsequent reclamation, the source of potential impact will be eliminated. For further discussion regarding the actual performance of the runoff and sedimentation control system at the Oak Creek Loadout facility, see the Surface water portion of this document.