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1.2 Precipitation <br />Table P and the associated charts exhibit the seasonal precipitation that has occurred near the mine <br />in Palisade, Colorado over the past 11 years. The overall average annual precipitation for the past 101 <br />years is 9.93 inches while the monthly average ranges from 0.54 inches in January to 1.22 inches in <br />September. Average winter precipitation is 1.68 inches while spring, summer, and fall averages 2.82, <br />2.28, and 3.15 inches, respectively (Charts P1 and P2). Review of Chart P1 further reveals that seasonal <br />precipitation in the past 11 years has been variable ranging from 0.53 inches to 6.22 inches, with the <br />higher values consistently occurring in the fall. <br />Perusal of Chart P2 indicates that precipitation for the 2010/2011 growing season was slightly below <br />average at 88% of normal. Summer and fall precipitation following the 2010 sampling effort can be <br />considered near average (106% and 94% of normal, respectively); while winter precipitation was well <br />below average at 43% of normal precipitation. Spring moisture is essential for the health and vigor of <br />cool season plants, while adequate summer precipitation provides development potential for warm - <br />season species later in the growing season. Spring precipitation was back to near normal levels with <br />95% of average precipitation in 2011. The timing and volume of fall and spring precipitation for the <br />2010/2011 growing season contributed to abundant cheatgrass populations on the mine and surrounding <br />native areas. This invasive annual grass, ubiquitous throughout the West, germinates in both the fall and <br />spring and rapidly exploits available soil moisture and nutrients early on in the growing season. <br />Cheatgrass develops rapidly, giving it a competitive advantage over native, perennial plants. The months <br />of October and May are particularly important for cheatgrass germination and growth. These two months <br />received 119% and 147% of average precipitation, respectively, during the 2010/2011 growing season. <br />Collected data in 2011 are therefore reflective of near - average vigor and production for perennial <br />vegetation in addition to overly abundant cheatgrass cover on both the reclamation and reference areas. <br />CEDAR CREEK ASSOCIATES, Inc. <br />Page 5 Snowcap - Revegetation Evaluation - 2011 <br />Monitoring <br />