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The nature of the fault geometry within the mineable portions of the Twentymile Park Basin have made it difficult to accurately predict small displacement faults L seam thickness of ]0 feet) within a virgin mining district. Once • two or more gate roads have been developed, the accuracy of predicting the linear features improves greatly. Several attempts have been made to use seismic methods to map the lateral fault traces well in advance of mining in the West and East Mining Districts. Interpretation of the available seismic data (varying fromolder high resolution shots, recent 93 mini thumper and regional oil exploration lines) to date has not yielded an accurate tool for small offsets. The seismic, however, has greatly improved the overall mapping of larger structures. The 9 Right fault that was encountered in July 1995 has seismic lines crossing perpendicular to its strike approximately 800 and 1,400 feet to the south. None of the lines clearly defined a fault offset. The poor to moderate seismic results are partly the result of the small offsets (most less than ] 0 feet) and the rapid scissoring of the lateral faults. The 9 Right fault is a good example of how the scissoring and splintering nature of the local faults (Exhibit 9B , 9 Right Gateroad Faulting) can produce little or no vertical displacements along the lateral faults' strike. The faults encountered produced minor inflows of water, and the measured flow from the fault at XC-36 produced 10 gpm; the fault at XC-47 produced 20 gpm. The measurement was obtained during July, 1995. The water temperature of the flow was 66 degrees and 70 degrees, respectively. A sample from each of the inflow points was obtained and sent to the laboratory for full-suite analysis. Only temperature was obtained and no field pH and EC measurements were made due to equipment problems. The lab results for the two samples, as presented in Exhibit 9B, are inconclusive and indicate the source of the water may be from the Wadge Overburden. Additional sampling will be conducted to try to verify the sourceof the water. Exploration holes drilled within the planned permit area are identified on Map 5, Surface Geology. Groundwater .vas encountered within the Twentymile Sandstone, the strata immediately above and including the Wadge Seam, and also within the Trout Creek Sandstone. Complete chemical analyses of the Wadge Seam are presented in Exhibit 10, Geochemical Analysis of Wadge Seam. Data from the following drill holes are presented: 006-82-46, 006-82-48, 006-82-48A, CH-82-58, CH-82- 59, CH-82-28, CH-82-71, 021-81-022, 021-81-011, 021-81-020, 027-82-033, and CH-82-36. No significant amounts of acid-forming ,toxic-forming. or alkalinity-producing materials have been identified with the coal seam. Lateral continuity and consistency of the Wadge Seam is good to excellent. Sample locations are illustrated on Map 12, Sample Locations. Lithologic characteristics, physical properties, and chemical analyses of the stratum immediately above (0-]0') and immediately below (0-5') the coal seam are presented in Exhibit 11, Geochemical Analysis of Wadge Seam Overburden. Samples were analyzed for all soluble salts and toxic elements listed in the "Guidelines for the Collection of Baseline Water Qualiry and Overburden Geochemistry Data" (CMLRD, 1982). Data from the following drill holes are presented: CH-82-74c, CH-82-68, CH-82-64, CH-82-67, CH-82-59, CH-82-29, CH-82- 14, and CH-82-54. Sample locations are illustrated on Map ]2, Sample Location. Lithologic logs of these drill holes are included in Exhibit 12, Lithologic Core Logs. EMD (Panel 2 Right through 6 right)(PR 97-04) The geology for the EMD is the same as that presented in Permit Revision No. 93-03. However, Table 6B, 1997 PR 97-04 Federal Reserve Calculations for the Eastern and Northern Mining Districts, which is considered to be confidential, presents the federal reserves that will be mined in the remainder of the Eastem Mining District and the Northern Mining District. The detailed Wadge Seam structure is shown on Map 6, Wadge Seam Structures. The geochemical data presented for PR 93-03 is used for this revision as well. • APPkaOViD JJN •> S 2000 PR 99-OS 2.04-16 5/25/00