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extensive irrigation systems set up when the azea was originally developed, it is reasonable to conclude that this • segment of Fish Creek is not conducive to flood irrigation. The alternate to flood irrigation is the utility of subirrigation to enhance crop production. The potential for subirrigation to occur depends upon depth of rooting of selected species and water table elevation during the Bowing season. Data collected previously by P & M indicate there are restricted areas in which subirrigation does occur. The extent of this, based upon vegetation type, was verified during the 1997 growing season by vegetation production studies within the defined Fish Creek AVF. The area that TCC is proposing to undermine in the Fish Creek drainage is located in parts of sections 10 and 11 of TSN, R86W is identical to the area that P&M Coal Company was planning on undermining and subsiding in its proposed Fish Creek Mine. P&M contracted with the consulting firm of Kaman Tempo to prepaze a report responding to the requrements of Rule 2.06.8(4). This report has been incorporated into Exhibit 7e-2. The soils information presented in the Kaman Tempo report was updated with the work performed by Habitat Management, Inc., and a copy of their report is presented in Exhibit 7e-4. Additionally, chemical and physical properties of the Binco Silty/Clay Loam are presented in Table 73. None of the data presented indicates a problem with this soil, for example the low SAR's indicate that leaching will not be problematic downstream of the mined area. The original data presented on this table was taken from Table 72 of permit C 81-071. The conclusions presented in the report agree with TCC's opinion that subsidence of the alluvial valley floor will not materially damage the existing ranches. It should be noted that the Kaman Tempo report was prepazed in 1982 and since that time the management practices have not changed, i.e. large acreage ranches to meet the economic requirements of the marketplace. This ownership pattern continues in the Twentymile Pazk basin. The ownership patterns are reflected on Map 1, Surface Ownership. TCC contracted with SubTerra, Inc. to expand the subsidence predictions to further evaluate impacts to Fish Creek • and its alluvial valley floor. This report is presented in Exhibit 7e-6, Twentymile Coal Company, AVF Subsidence Report, Final Report. The report provides a numerical analysis of approximately 200 cross-sections through the subsided area, and also used a 3D Geologic Modeling software program (GEMCOM) to compare against the mathematical model. The results of the mathematical model show that of the 25.5 acres in the alluvial valley floor approximately 7.3 will be impacted by subsidence during normal flow periods and 12.3 acres during high flow periods. In reference to a change in the gradient of Fish Creek, SubTerra analyzed the creek from stations 0 + 00 to 100 + 00. The analysis included evaluating the gradient both before and after mining. The result of this analysis is presented on Table 2 and 3 in the report. Also, the narrative includes a discussion of change in gradient of the creek. The gradient change in this segment of Fish Creek is approximately 0.6%. There are two landowners associated with the undermining and subsiding of Fish Creek, those being, Camilletti and Sons and the State of Colorado. In reference to Camilletti and Sons, they own approximately 920 acres in the immediate area of the mine, 3,500 acres in various sections of T6N, R86W and approximately 1,040 acres in T7N, R86W. The mining of panel 18 Right will impact the property within the immediate area of the mine. Personal communication with Mr. Frank Camilletti of Camilletti and Sons indicates that this acreage is not critical to the continued operation of the ranch and will not materially damage it. This area is not cropped and is treated as unimproved rangeland. TCC conducted a vegetation study of the adjacent upland area and the bottomlands to evaluate the productivity of the respective areas. The study is presented in Exhibit 7j-1, Northern Mining District, Fish Creek Vegetation Study. The data presented in the study verifies TCC position that the productivity between the two areas is not different enough to warrant any conclusion different than TCC's. • The State of Colorado is the surface owner of the parcel, located in the SW/4 of Section 10, TSN, and R86W, to be undermined and subsided. As presented above, the mining of this panel will flood a total of 4.4 acres. As is the case for all the lands along Fish Creek to be undermined and subsided no flood irrigation system has been PR03-06 2.06-25.5 05/07/03