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1. The proposed mining operations will not interrupt, discontinue or preclude farming on <br />the alluvial valley floor. <br />The mine plan for the Eastern Mining District was shortened from the originally <br />proposed panel length for longwall panels 9R and 8R. Longwall panels in the Eastern <br />Mining District did not undermine the Foidel Creek/Middle Creek Confluence AVF. <br />Longwall panels 6RT through 2RT in Eastern Mining District presented in PR -04 <br />undermined a portion of Middle Creek; however, the affected portion of Middle Creek <br />is not designated as an AVF. <br />Regarding PR -10, a small section of Foidel Creek above the confluence of Middle <br />Creek will be undermined with the 5 RT gateroad in the WCR. A very small increase <br />in surface area of Foidel Creek and no surface area increase in Middle Creek is <br />predicted resulting from mining in the WCR proposed with PR -10. A potential <br />increase in subirrigation may increase productivity in the upland areas surrounding <br />Foidel Creek. The potential for fissures development and water loss (stream pirating) <br />is very low. The AVF will be monitored in accordance with the plan included in <br />Exhibit 4E-11 of the permit. <br />2. The proposed mining operations will not cause material damage to the quantity or <br />quality of surface and ground water that supply the alluvial valley floor. <br />As discussed in the PHC Section of this document, significant dewatering of the Foidel <br />Creek or Middle Creek stream/alluvial systems due to undermining would be <br />precluded by the low vertical permeabilities between the Wadge seam and the alluvia. <br />Stream flow loss to surficial tensional cracks which may develop is expected to be <br />minimal and the fine-grained nature of the alluvium will rapidly fill any cracks that <br />may develop. Furthermore, surface cracking due to subsidence is typically limited to a <br />maximum of 50 feet in depth and direct connection to the workings is not anticipated <br />due to overburden depths in this area in excess of 600 feet. Also, any stream flow loss <br />will be more than compensated by the projected and existing mine discharge to Foidel <br />Creek averaging over 600 gpm. And lastly, the entire Foidel Creek/Middle Creek <br />Confluence alluvial valley floor is flood irrigated by water diverted from the <br />unaffected segment of Trout Creek above its confluence with Middle Creek, nullifying <br />any temporary, minor impacts which could occur. (See TC Life of Mine Application <br />Map No. 15). <br />The primary function of the Foidel Creek/Middle Creek Confluence AVF is the <br />support of flood irrigated hayland. As previously noted, the flood irrigation water is <br />not diverted from affected segments of either Foidel Creek or Middle Creek, but is <br />diverted from an unaffected segment of Trout Creek. A field inspection conducted by <br />the Division in late August of 1986 observed vegetation on the flood irrigated AVF to <br />be more robust than adjacent areas upstream on Foidel Creek above the Trout Creek <br />irrigation diversion (assumed to be subirrigated). The flood irrigated pasture was <br />dominated by pasture grasses while weedy species were visually dominant on the <br />non -irrigated reach (see vegetation data in supplemental Report of 9/22/86). From <br />Page 50 of 52 <br />