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Febnrary 2006 Hayden Gulch Terminal, Inc ' Hayden Gu1rb Mine - 2005 AuaualRedamatiou Report •Page 4 <br />• Parcel E - 60.8 percent total foliar cover <br />• Parcel HG-8 - 57.4 percent total foliar cover <br />• Parcel 003 - 55.4 percent total foliar cover <br />• Slump Area - 51.7 percent total foliar cover <br />2.2.2 Woody Plant Density <br />The woody plant density data is shown on Figure 2, 2005 Woody Plant Density Data. The overall <br />average woody plant density of Pazcels E, HG-8 and 003 (1,767 stems per acre) exceeded the <br />performance standard of 750 stems per acre. <br />2.2.3 Species Diversity <br />The species diversity standard is 90 percent of the reference area mean, which was 14.2 species <br />per 100 square meter (performance standard = 12.8 species per square meter). All four parcels <br />exceeded the performance standard value. <br />The species diversity in the permit area was generally similar to the reference area. Introduced <br />species were the dominant life forms. Introduced perennial grasses were the dominant life form in <br />all areas - Bromopsis lnermis (smooth brome) was generally the most common introduced <br />perennial grass species followed by Thinopyrum intermedium (Intermediate wheatgrass). The <br />introduced perennial grass relative percent cover value for the reference area was 65.6 percent. <br />The introduced perennial grass relative percent cover value for the four parcels that comprise the <br />permit area was 72.1 percent. Introduced perennial forbs were the second most common life form <br />in the reference area (20.1 percent). Shrubs were the second most common life form in Parcels E <br />and HG-8 (15.0 and 8.1 percent, respectively), while native perennial grasses were the second <br />most common life form in the Slump Area (6.7 percent). <br />2.2.4 Sample Adequacy <br />HGTI and CDMG representatives discussed sample adequacy requirements during discussions on <br />the vegetation sampling plan during July 2004 (Sandy Brown, 2004). Because of the small size of <br />the four parcels, CMDG staff indicated it was unnecessary to use the standard sample adequacy <br />formula to determine minimum sample size, However, CDMG staff did request that the reference <br />area sample size should be at least a minimum of five samples to assure the weighted mean value <br />was representative of the cover conditions for the reference area. <br />Table 1, Sample Adequacy for 2005 Cover Samples, summarizes the sample adequacy <br />requirements for each sampling unit using the standard sample adequacy formula presented in the <br />Bond Release Guideline (CDMG, 1995). The table shows the sample size (n) for the reference <br />area in 2005 was 10, which both meets the CDMG's requested minimum sample size of five and <br />the adequacy formula derived sample size. Furthermore, the calculations show that even with <br />small sample sizes for the individual parcels (n varied between three and five), the minimum <br />sample size requirement was either met, or was just slightly less that the formula calculated size. <br />Hydro-Environmental Solurions, Inc. <br />P.O. Box 771996 <br />57 10a Street, Suite B <br />Steamboat Spnngr, CO 80477 <br />970-871 d 125 <br />