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III. Map: <br />The monitoring locations for the second half of 2003 are shown on the Second Half of <br />2003, Subsidence Map. The map also indicates the location of the longwall face on a <br />monthly basis. <br />IV. HvdroloQic Monitoriue: <br />The 15 Right Panel has two alluvial wells and two surface sites associated with it. The <br />sites are shown on the attached Second Half of 2003 Subsidence Map. The upstream <br />alluvial well is designated by the title AVF-13 and the downstream alluvial well by the <br />title AVF -14. The upstream site is known as SW -13 and the downstream site is known <br />asSW-14. <br />The 17 Right Panel has one alluvial well and one surface site associated with it. The <br />alluvial well (downstream of AVF-14) is designated by the title AVF-15 and the <br />associated surface site (downstream of SW-14) is known as SW-15. These sites were <br />installed to provide non-subsidence downstream sites, following subsidence of AVF-14 <br />and SW-14. The monitoring sites are shown on the attached Second Half of 2003 <br />Subsidence Map. Period of record data tables for these sites are also attached. <br />Hydrologic monitoring did not indicate significant impacts to Fish Creek, however <br />elevated iron concentrations were detected in surface water quality in June 2003 (which <br />subsequently dropped during an August 2003 sampling episode). In addition, iron and <br />manganese concentrations appeared elevated in the new alluvial wells during August <br />water quality sampling. Hydrologic monitoring of these sites will continue in 2004, and <br />this anomaly will be monitored and assessed. <br />V. Conclusions: <br />Structures remained essentially unaffected during the period with the exception of the <br />predicted impacts to the Union Pacific Railroad and Fish Creek. No adverse impacts, i.e. <br />imminent failure of structure, were evident with regard to these structures. <br />Subsidence monument surveys disclosed no unusual developments during the reporting <br />period. Subsidence magnitudes and projected draw angles were within the anticipated <br />ranges previously documented for the area. The angle of draw in the North Mining <br />District ranges between 17.5 to 19.5 degrees as follows. Survey data indicated the angle <br />of draw to be approximately 17.6 degrees for the 14 Right panel in the vicinity where the <br />railroad track crossed the head gate entry. Survey data over the 13 Right panel indicated <br />the angle of draw to be approximately 19.4 degrees in the vicinity where the railroad track <br />crossed the head gate entry. Survey data over the current 15 Right panel indicated the <br />angle of draw to be approximately 18.8 degrees in the vicinity where the railroad track <br />crossed the head gate entry. <br />2003_2ndHa14SubReport Page 2 of 2 02/09/04 <br />