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--. -r. Incidentally, it is not taken lightly by OCM that the reference area could be impacted. However, impact is in part the result of the original baseline study design. The original consultants very nicely saved a previous operator money by deciding that the affected area and the reference area would be one in the same. Thus, only half the vegetation work was necessary. However, because the affected area (defined as natural areas immediately surrounding the actual disturbed area) is contiguous with the disturbed area, the only way to expand the mine operation in an area attached to the present disturbance is to drive through the reference area. 3. Reference area samples within the vicinity of the proposed disturbance do not indicate that the location is unique or different from other portions of the reference area. The portions of the reference area that are closest and most consistent with areas proposed to be disturbed were compared to the other samples spread throughout the reference area. For the mountain shrubland community, cover samples 5, 17, 6, 2, and 11 and production samples 5, 26, 22, 38, 37, 6, 27, 17, 43, 58, 39, 2, 57, and 11 were in the vicinity of and similar in exposure to the proposed disturbance. The closest juniper woodland reference area samples were 6, 1, 7,and 3 for total cover and 6, 48, 1, 57, 40, 7, and 3. Statistical comparison (Students t-tests per page 16 of the Division's Guidelines for Compliance with Land Use and Vegetation Requirements of the Colorado Mined Land Reclamation Board for Coal Mining. October 1988) contrasting the samples near the proposed disturbance with those farther away indicates that the two sets of data are statistically similar for both parameters and both communities. The highest calculated t value was 0.308 (JW production), well below the table values at the 90% confidence level which indicates that the baseline samples nearest the proposed disturbance were no different from those found elsewhere. The disturbed areas near these reference samples can reasonably be expected to be very similar to the portion of the reference area nearby. Therefore, it is reasonable to expect that the present reference area sufficiently reflects the area in question. The combination of small size and proximity to comparable sampled areas has led OCM to request that the Division recommend that no sampling be required if the disturbance is proposed in an upcoming permit revision. Please do not hesitate to contact me at the above address or phone number if you have any concerns or questions. Sincerely, ~~~ Matthew S. Hayes President CC: Tom Anderson, OCM ]im Stover, 1.E.Stover and Associates