2011-01-18_REPORT - C1981041 (2)

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and standards. Per Cedar Creek's recommendations based on that evaluation, modest revisions to success criteria and standards are being proposed to facilitate a reasonable solution to a problem that currently has no ecological resolution. Extensive discussion of these proposed revisions to the success criteria are presented in Appendix B. Recommended criteria and standards are summarized as follows (changes /clarifications are in boldface): • Achieve 90% of the perennial vegetation cover of the approved reference area. • Achieve 90% of the total herbaceous production of the approved reference area. • Achieve woody plant density of 800 live shrubs per acre. • Achieve total perennial cool- season grass species' relative cover of 2 :0.5% with at least two species present in the reclamation (observed). • Achieve total perennial warm - season grass species' relative cover of >_0.5% with at least two species present in the reclamation (observed). • Achieve total perennial forb and suffrutescent (sub- shrub) species' relative cover of >_0.5% with at least two species present in the reclamation (observed). • And, no reclaimed area shall have a single species that represents greater than 70% relative cover, with the exception of annual grasses. The annual grass component shall not exceed 70% relative cover unless the annual grass component in the corresponding reference area also exceeds 70 %. In such instances, the relative cover of the annual grass component of the reclaimed area shall not exceed the relative cover of the annual grass component in the reference area by more than 5 %. 1.3 Precipitation Table P and the associated charts on the following page exhibit the seasonal precipitation that has occurred near the mine in Palisade, Colorado over the past 10 years. The overall average annual precipitation for the past 100 years is 9.96 inches while the monthly average ranges from 0.54 inches in January to 1.23 inches in September. Average winter precipitation is 1.69 inches while spring, summer, and fall averages 2.81, 2.28, and 3.20 inches, respectively (see associated charts). Review of the precipitation charts further reveals that seasonal precipitation in the past ten years has been variable ranging from 0.53 inches to 6.22 inches, with the higher values consistently occurring in the fall. The weather station used to collect precipitation data (COOP Number 56266 Palisade, CO) had no measurements for July — September, 2009 or for March & August, 2010. Therefore, the average monthly total for the missing data was used for substitution. Examination of surrounding weather stations reveals that spring precipitation was slightly higher than average and the summer was about average. Perusal of the last chart indicates that precipitation for the fall, winter, and spring prior to sampling can be CEDAR CREEK ASSOCIATES, Inc. Page 5 Snowcap - Revegetation Evaluation - 2010