1992-08-05_GENERAL DOCUMENTS - C1980005

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t the Fish Creek alluvial system and thus potentially damage the AVF in question. Refer to the groundwater section of this document for a more thorough discussion. The second process may impact both Fish Creek water quality and quantity contingent upon the activities at sediment pond outfalls NPDES 008 (Bond) and 004 (Cow Camp) . Therefore, only surface water potential impacts to Fish Creek via Bond and Cow Camp Creeks will be discussed. Seven surface water monitoring sites exist within the Fish Creek drainage: NPDES 008 and SW-S2-12 are located on Bond Creek. NPDES 004, SW-S2-6 and SW-S2-10 are located on Cow Camp Creek. SW- S2-11 and SW-S2-13 are located on Fish Creek upstream of Fish Creek's confluence with Cow Camp and downstream of Fish Creek's confluence with Bond Creek, respectively. We may consider variations in water quality between SW-S2-11 and SW-S2-13 indicative of impacts, if any, the Seneca II mine has on Fish Creek and its AVF, therefore. Additionally, Cyprus Coal Company, under the guidelines set in the C-82-056 permit for the Twentymile Park Mine, monitors two sites on Fish Creek, 1002 and 27-A which geographically correspond to SW-S2-11 and SW-S2-13, respectively. Thus we can compare water quality at 1002, upstream Cow Camp Creek, to 27-A downstream of Bond Creek not only to determine Seneca II impacts, if any, but also to roughly verify the water quality data submitted by Peabody. The attached graph sub-entitled, "Seneca II Fish Creek Impacts . . " indicates that there are some discrepancies between reported mean annual TDS levels by Peabody and Cyprus in 1987 and 1991. This may however be a result of differing monitoring times and frequencies. The utility of such a graph is unknown. It is therefore reasonable to consider Peabody's data as accurate and adequate to determine if the operation is or is not causing material damage to the quantity or quality of water in the surface water system that supplies the Fish Creek AVF. Both NPDES outfalls are monitored weekly for flow, conductivity, pH, and temperature and are sampled three times a year for water quality parameters listed in the "long" list on page 7-158 of volume four. Peabody monitors SW-S2-6 (Cow) monthly for instantaneous flow and field parameters from March through October. This site's samples are also analyzed using the surface water "long" list. SW- S2-10, 11, 12, 13 were established in 1987 and are monitored monthly, May - September. However, as a result of Technical Revision 20 (Approved 10/02/90) , when no flow exists at the Bond and Cow Camp confluences with Fish Creek, the two Fish Creek sites, SW-S2-11 and SW-S2-13 are not monitored. These new sites are again analyzed using the "long" parameter list mentioned above. Peabody's monitoring and monitoring plan in reference to the Fish Creek AVF remains in full compliance with 4.24.4 of the CSCMRA. AVF POTENTIAL IMPACTS: PEABODY PREDICTIONS Mining at Seneca II may effect both the quality and quantity of the surface water supplied to the designated Fish Creek AVF.