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SECOND HALF 2003 SUBSIDENCE SURVEY REPORT <br />I. Survey Data: <br />During the second half of 2003, subsidence survey data was collected periodically from <br />established monuments on the Union Pacific Railroad (UPRR) in areas underlain by gate <br />roads or panel centers during periods of mining in the 15-Right (Panel No. 15) longwall <br />panel. As is reflected in the data and on the attached subsidence map, the 15-Right <br />longwall panel did not directly undermine the Walcott, Hayden-Gore Pass and Western <br />Area Power Administration power lines, and Foidel Creek during the second half of <br />2003. <br />The data and frequency for the survey monuments along the UPRR are presented in the <br />attached Table No. 1. Portions of the Fish Creek were undermined by the 15 Right Panel <br />during the second half of 2003. The post mining survey of Fish Creek in areas underlain <br />by the 15 Right gate road or panel center will be completed in the summer of 2004 as <br />weather permits. The post mining subsidence profile for Fish Creek over Panel 14 Right <br />and the pre mining subsidence profile for Fish Creek over Panel 15 Right are submitted <br />as one drawing with this second half 2003-subsidence report. <br />II. Structures: <br />Structures affected during the second half of 2003 reporting period include the Union <br />Pacific Railroad. <br />Visual inspections of the Union Pacific Railroad by UPRR personnel were conducted <br />from August 25, 2003 through September 14, 2003. <br />Daily surveys and observations of the UPRR over Panel 15 Right were also performed by <br />Twentymile Coal Company personnel from August 21, 2003 through November 21, <br />2003. A follow-up report on the survey data and observations was submitted to various <br />personnel From the UPRR on a daily basis. Apre-miming "humping" of the railroad <br />track with ballast was performed in August 2003, prior to undermining of the track in <br />August and September 2003. Final re-leveling of the rail line to the post-mining target <br />level will be performed by the UPRR in the mid to late summer 2004 as needed. A <br />follow-up survey will be performed at that time. A final report will be submitted to the <br />UPRR subsequent to these surveys. <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 regazd to these structures. <br />No other repair work was required to the Union Pacific Railroad as a result of TCC's <br />mining activity. <br />2003 2ndHalfSubReport Page 1 of 2 02/09/04 <br />