2008-03-03_PERMIT FILE - C2006085 (14)

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• Prior to commencing the 2007 field sampling and during the preparation of this baseline vegetation monitoring report, the vegetation sampling requirements found in Section 4.15.11 of the DRMS regulations were reviewed and discussed with Ms. Sandy Brown of the DBMS regazding the proposed sampling methods and data analysis methods to be used. Agreement on the sampling methodology used in this evaluation as well as a proper understanding of the recently enacted regulatory amendments was obtained from the DRMS prior to initiating field sampling. In this evaluation, the vegetation parameters of production, plant cover, species diversity and shrub density were sampled. It is expected that these data will be utilized to evaluate the successfulness of revegetation efforts with respect to plant cover, herbaceous forage production, species diversity, and shrub density. In addition, during the actual field sampling effort, Ms. Sandy Brown and Mr. Dan Mathews of the DBMS inspected the site and additional details were discussed with them at that time. Vegetation Mapping: The boundaries of the vegetation types in the proposed Northfield Mine Project facilities area were mapped by walking the vegetation boundaries with a GPS unit as required in Section 2.04.10(1) which requires that plant communities will be delineated based upon the basis of visually dominant plant species. Two plant community types were found to occur in the area proposed to be affected by the proposed mine facilities area aJuniper- Grassland Vegetation Type and a Disturbed Vegetation Type. The Juniper-Grassland Vegetation Type, was found to occupy most of the proposed mine facilities area. This vegetation type is dominated by an overstory of One-Seeded Juniper (Juniperus monosperma) with an understory dominated primarily by Blue Cmama (Bouteloua • gracilis) and Red Three-awn (Aristides longiseta). The Disturbed Vegetation Type corresponds to areas that have been disturbed by previous actions on this site such as areas of mine exploration roads, irrigation ditches, the old Chandler Mine railroad bed and a section of Chandler Creek that was realigned either as a result of railroad construction work or the construction of a large flood control berm that was constructed along the southeastern portion of the site. Examination. of historic photographs shows that Chandler Creek was realigned over a considerable section of the site and that the excavated filled obtained from this new stream alignment was placed into an older section of stream channel to the north of the existing drainage channel. Transact Locations. To ensure that all of the areas within each corresponding vegetation disturbance areas or reference area, had an equal chance of being sampled, each proposed sample azea was treated as a single sample unit and a totally randomized sampling effort was implemented. Utilizing the prepared vegetation maps, the extreme north, south, east and west boundaries of each vegetation site sampled were converted to the 1982 Colorado State Plan South Zone (NAD 82) coordinate system. The interval used in the state plan coordinate system is based on foot increments. Given the typical real-time accuracy of this GPS unit of plus or minus 18 inches, all of the transact locations were field located at a sub-meter accuracy. Once the boundaries of the proposed disturbance areas or reference areas were identified, then using a specially prepared computer program which generates random coordinates, the potential transact location coordinates were identified. These coordinates were then entered into the GPS • 2