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RULE 4 PERFORMANCE STANDARDS <br /> Determination of Seedling Emergence <br /> At each emergent density sample point (revegetation monitoring only), five one-square foot <br /> quadrats should be blindly tossed to the ground and the number of emergents rooted within the <br /> perimeter of each shall be recorded accordingly into one of five classes: perennial grass,perennial <br /> forb, shrub, annual grass, or annual forb. Where possible recognizable taxa may be recorded by <br /> species. Efforts with 1 — 2 perennial emergents per ft2 are considered to be fair, 2-3 perennial <br /> emergents per ft2 are considered to be good, while 3-4 perennial emergents per ft2 are considered <br /> very good. Five or more perennial emergents per ft2 are considered to be excellent. <br /> Sample Adequacy Determination <br /> Sampling within each monitored unit shall be conducted to a minimum of 5, 15 or 20 samples as <br /> necessary. Sampling within each unit under consideration for bond release shall start with a <br /> minimum of 15 (reference area) or 20 samples (revegetated area) and continue until a statistically <br /> adequate sample(if necessary)has been obtained in accordance with Section 4.15.11 (2)(a). From <br /> initial sampling efforts,sample means and standard deviations for total non-overlapping vegetation <br /> ground cover, production, and woody plant density will be calculated. For bond release <br /> applications,the typical procedure is that sampling continues until an adequate sample, nmin,has <br /> been collected in accordance with the Cochran formula(below)for determining sample adequacy, <br /> whereby the population is estimated to within 10%of the true mean(µ)with 90%confidence. For <br /> woody plant density, the estimate is to within 15%of the true mean. <br /> When the inequality (nmin<n) is true, sampling is deemed adequate; and nmin is determined as <br /> follows: <br /> Nmin = (t2s2)/(dx)2 <br /> where: n = the number of actual samples collected(initial size= 15 or 20) <br /> t2 = the value from the one-tailed t distribution for 90% confidence with n-1 <br /> degrees of freedom(a value of approximately 1.3); <br /> s2=the variance of the estimate as calculated from the initial samples; <br /> d=precision(0.10 for cover and production or 0.15 for woody plant density; <br /> z=the mean of the estimate as calculated from the initial samples. <br /> If the initial samples do not provide a suitable estimate of the mean (i.e., the inequality is false), <br /> additional samples should be collected until the inequality (nmin < n) becomes true. However, <br /> where sampling is for managerial (monitoring) information, adequacy is not necessary and is <br /> calculated for informational purposes only. <br /> If reverse-null testing will be utilized to document success, then in accordance with Rule 4.15.11 <br /> (2) (c)a minimum of 30 samples must be collected and a demonstration of sample adequacy is not <br /> necessary In this cirenmctanee a twn-camp1 reverce null t-tect is mandated along with <br /> Satterthwaite approximated degrees of freedom and standard error. However, if an adequate <br /> Rule 4 Performance Standards 4-67 Revision Date: 12/20/19 <br /> Revision No.: TR-135 <br />