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West Elk Mine draw observed during the aforementioned survey will be submitted to the Division with the semi- annual subsidence report. To verify the subsidence angle-of--draw in the SOD area, MCC will perform a baseline survey over at least 5,000 feet, or the entire length of the panel (whichever is shorter of the first or second E-seam panel, prior to the start of longwall mining, with survey- grade GPS equipment. The determination of which E-seam panel is surveyed first is dependant upon access conditions and mine plan timing. The survey will consist of using asurvey-grade GPS system to locate stations on approximately 300 foot intervals on the longitudinal axis of each panel. Each station, or point, will be measured for location and elevation. Two survey lines per panel will also be established perpendicular to the longitudinal axis. The points on these two transverse lines will be placed on approximately 100 foot spacing within the panel (see figure 21A and Map 68) then at approximately 50 foot intervals within approximately 100 feet of the inside edge and for at least 700 feet past the outside edge of the panel. If the survey is initiated at the beginning of mining of a longwall panel, the first segment of the longitudinal axis survey will be conducted using the monument spacing prescribed for the transverse line surveys. In essence, the initial survey monument will be located at least 700 feet outside the edge of the panel on the longitudinal axis followed by monuments being placed on the axis at approximately 50 foot intervals to a point located at least 100 feet inside the end of the panel. The next monument within the panel will then be placed approximately 300 feet further into the panel along the longitudinal axis. A discussion on how the verification will be made is discussed under the heading Verification and Accuracy of Predictions below. In addition to the GPS surveys, MCC will conduct visual surveys, and any necessary traditional surveys, semiannually each year and provide the information in a written report by the end of September and April each year. A summary of the visual observations and monitoring will be provided in a quarterly letter report to CDMG and to the USFS. If any mechanical response is detected during these visual inspections that is not consistent with what has been previously observed, MCC will notify CDMG within ten working days of our observations. The reports of the visual surveys will include photographs to document any subsidence features, including cracks, rockfalls, landslides, revegetation, and other relevant features. A map will also be included that identifies the location of the photographer and the aspect of the image for each photograph. An additional map will be prepared that identifies the location and extent of the observed features. MCC will attempt to revisit previously identified subsidence features to note any changes that have occurred since the previous visit. MCC will also attempt to replicate the aspect of the photographs taken previously to document the progression of subsidence and subsequent healing. The discussion of the field observations will in particular address the development and healing of the subsidence features, utilizing the photographic documentation. In addition, MCC will discuss baseline conditions observed in areas prior to undermining. The report will document how the inspection was conducted, and include such observations as weather and ground conditions. In addition to performing the visual surveys, aerial or other type photos will be taken prior to beginning mining in an area, periodically during mining, and after mining when subsidence is complete to document landslides, rockfalls, vegetation, etc. over the areas being mined. This 2.05-163 Revised June 2005 PR! 0, Rev. March 2006; May 2006 PRIG, Nov. 2006TR107