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• contained in the Seneca II-W permit. Aline that indicates 90 percent of this standard has been placed on Figure 1 for informational purposes. At such time as bond release is formally sought, revegetation will be considered successful for cover when mean cover for a bond release block is at least 90% of the calculated success standard or approved technical standard. WOODY PLANT DENSITY: For purposes of comparisons in this document, woody plant density at the Seneca II-W Mine is evaluated using a technical standard of 2000 shrubs per acre. Climatic Data Precipitation data were collected at the Seneca II-W Mine during 1998, 1999, 2000. For all previous years, SCC provided precipitation data from the nearby Seneca II Mine for the period of January 1982 through December 1997. Since the data record for that mine exists for only 17 years, the long term average monthly precipitation data from the National Oceanic and Atmospheric Administration (NOAH) for the nearby town of Hayden was used as an appropriate base for comparison. Information on degree-days was based on temperature data derived from the NOAH records at Hayden. RESULTS Data from the 2000 revegetation monitoring studies at the Seneca II-W Mine are presented in Tables 1 through 19 contained in Appendix 1. The list of plant species observed during these studies (reclaimed and reference areas) are included in Table 20 in Appendix 2. Seed mixes used in the reclamation areas are included for reference in Appendix 3. Photographs of representative locations within the reclaimed areas sampled in 2000, as well as photographs of the Aspen, Mountain Brush, and Sagebrush reference areas are included in Appendix 4. Graphic depiction of summaries of vegetation and climate data are presented in Figures 1 through 10 of this report. • In the cover descriptions below, species listed as "also present" were not "hit" during point- intercept sampling but were present within one meter on either side of the 50 m sample transect line. Cover percentages referred to in the following results as "percent of total vegetation cover" are relative vegetation values. 1993 Reclaimed Area (Photographs 1 through 4) Cover (Table 1) Native perennial cool season grasses were the dominant species in this area and provided 59.9 percent of total vegetation cover. Agassiz bluegrass (Poa agassizensis) and mountain brome (Ceratochloa Carinata) contributed three-fifths and one-tenth of this lifeform's total, respectively. Other major contributors were western wheatgrass (Pascopyrum smithii) and slender wheatgrass (Elymus trachycaulus). Six other species made measurable contributions to total vegetation cover. Native perennial (orbs contributed 13.1 percent of total vegetation cover. Two-groove milkvetch (Astragalus bisulcatus) contributed one-third of this total. Together, blue flax (Adenolinum lewisi~) and American vetch (Vicia americans) averaged another third. The remaining third was comprised of nine species. Introduced annual and biennial forbs contributed 9.8 percent of total vegetation cover. Twolobe speedwell (Pocilla 6iloba) was the dominant species in this lifeform and contributed more than three-fifths to the total. The balance was comprised of salsify (Tragopogon dubius ssp. major), prickly lettuce (Lactuca serriola), and Jim Hill mustard (Sisymbrium altissimum). Introduced perennial grasses contributed 7.2 percent of total vegetation cover. Orchard grass (Dactylis glomerata) contributed more than two-fifths of this total. The balance was comprised of smooth brome (Bromopsis inermis), intermediate wheatgrass (Thinopyrum intermedium), Russian wildrye (Psathyrostachys juncea), and meadow • brome (Bromopsis riparius). Introduced perennial forbs averaged 3.9 percent of total vegetation cover. Cicer milkvetch (Astragalus cicer) and alfalfa each contributed two-fifths of this total and Canada thistle (Braes arvensis) comprised the balance. Native shrubs comprised 2.1 percent of