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location of the exposed walls where discontinuity measurements were collected <br />for this study. Data were collected on February 24 and 27, 2004 during atwo- <br />week equipment maintenance period for the quarry when the majority of quarry <br />operations was shutdown; and therefore, did not interfere with normal production <br />mining activities. Discontinuity measurements were obtained utilizing a Brunton <br />compass both indirectly by sighting along the discontinuity surface; and where <br />deemed safe, by direct measurement on the discontinuity surface. <br />A total of 202 discontinuity measurements were collected and added to the <br />measurements from previous years. When combined with data collected from <br />previous annual reports and with borehole geophysical data collected during the <br />2003 geotechnical investigation, a total of 2,716 strike and dip measurements of <br />major discontinuities in the quarry have been obtained. Figure 4 is a <br />stereographic plot of ail of the data poles representing structural features. The <br />triangle and square shaped symbols represent the new data collected for this <br />report, while the circles represent the borehole data from 2003, and the diamond <br />symbols represent the data collected for annual reports from 1997-2002. By <br />identifying the data with the year it was obtained, deviations or trends in <br />discontinuity orientations can be monitored as mining continues and the pit is <br />expanded. <br />In the southern expansion area, multiple temporary highwalls were exposed at <br />the time of our data collection (Figure 2), and approximately 130 points were <br />collected from this newly developed mining area. The remaining 70 datapoints <br />were collected from the middle level of the quarry, along temporarily exposed <br />north, south, east and west oriented highwalls. <br />An adequate evaluation of the structural geologic conditions of the quarry must <br />also include accurate information regarding the long-term orientations of the pit <br />walls. The wall orientations utilized in this report are based on the most recent <br />mine plan developed by Lafarge West, Inc. in December, 2003 and match the <br />current Colorado Division of Minerals and Geology mine plan (Figure 5). These <br />-5- <br />