2018-05-30_PERMIT FILE - C1981022A

Home Browse Search

09/14/2005 12:04 19709295177 OXBOW MINE PAGE 03103 Sir- 2.OS.6 and use will either not be impaaed or any impacts will be minimal Most of the seeps and springs in the area do not have associated water rights and OMI is committed to mitigate anysignificant adverse impacts to seeps or springs which aze beneficiallyutilizedtprough augmentation of anyeffected water rights, monetary compensation, development of alternative watering facilities such as guzzlers, or other appropriate mitigation measures. A copy of the Diusrart cf W/ater Rgawts:s Del Plmr c~ AuBrerua#auris included in Exhibit 2.04-E4, Hydrologic Information, Mine Water Transfer TR-47 describes the proposal to transfer water from the D seam Elk Creek mine water sump to the underlying abandoned Somerset Mme C seam workings via a surface borehole completed to the C seam workings. The source of water encountered in the D seam and pumped is water imported for dart control, motor cooling, etc. TR 50 provided the as-boil borehole completion information to the B/C seam workings and subsequent transfer of water. The eastern Somerset mine workings in the vicinity of Elk Creek showed a static water level at 6044' elevation. The borehole is located at the north end of the upper Elk Creek mine facilities area (see Map 2.05•Ml, sheet 3 of 5, General Facilities). Over 10 million gallons of water has been transferred from the active D seam workings to the abandoned B/C seam workings. .The abandoned B/C seam workings have an estimated available holding capacity in excess of 1 billion gallons of water. The C seam workings are connected to the underlying abandoned Somerset mine B seam workings via connecting boreholes, ventilation shafts and rock tunnels, etc. (see Map 2.04-M4B, "C' Seam Isopach). Groundwater information summarized in Annual Hydrology Reports (through yEaz 2004) show that the western B-seam workings are dry (H 30 and B-6 wells). It is expected that the transfer of water to the B/C seam workings will result in a temporary increase in water level locally in the old workings, but the water will dissipate and spread through the old workings (both B and C worlings). Given the vast voltune of space available is the abandoned Somerset Mme workings, it is anticipated that the comparatively rrriniaral volume of transferred water will never reach the B seam portals (located up-gradient of mine worlings at 6090' elevation) and will never be discharged to the surface. TR-51 provides for the completion of similaz water transfer boreholes in the vicinity of the Hubbard fansite. One borehole will transfer water from the D seam workings to the surface and the second borehole will transfer water to the B/C seam worings. In consideration of the August 2, 2005 MSHA approval, water transfer to the B/C workings in this vicinity will be limited to elevations below the 6046 foot elevation. Somerset mine B and C seam ponals were sealed using air seals (concrete blocks and dirt). These seals were not designed to be bulkhead seals for holding back water. There are no connections between the B and C seam workings within the abandoned Sanborn Creek mine workings. The workings are separated by considerable distance by coal barrier pillars. The Somerset C seam is located approximately 175 below the Elk ('leek Mme D seam There aze no known open connections between the Elk Creek Mme D seam workings and the Somerset C seam workngs. The two B/C seam water transfer boreholes will be monitored for water level at the frequency of the OMLLC groundwater monitoring program and the results reported in the AHR The annual volume of water transferred from the D seam workings to the B/C seam workings will also be reported in the AHR. Representative samples of transferred water will also be analyzed for pH and TSS with the resuks also reported in the AHR It is expected the hydrologic consequences of the transferred water to the abandoned Somerset mine groundwater regime will be negligible and will not impact groundwater or surface water outside of the pemut area. TR-51 2.(15-966 Revisrrl Crnrrmhn. inns