2011-03-30_REPORT - C1980005 ‎(2)‎

• Permit No: C1980005
• IBM Index Class Name: REPORT
• Doc Date: 3/30/2011
• Doc Name: 2010 Revegetation Report Part 2
• From: Seneca Coal Company
• To: DRMS
• Permit Index Doc Type: Reveg Monitoring Report
• Email Name: JDM
• Media Type: D
• Archive: No

• Cover
Sample Size 30
Minimum Adequate Sample Size 25
Assessment of BRB for Compliance with Phase 11 Performance Standards
Calculation of 90 percent of the cover performance standard appropriate for 2010 sampling is
demonstrated below and is based on the following information:
Vegetation Type
Allowable Herbaceous
Cover on a first -hit basis*
% of Pre - mining Area
Mountain Brush
12.4
83.0
Sagebrush
44.7
17.0
—1-0 wwus anv dnnuauuienmat pianr cover in excess or 7U /o or the
remainder.
2010 Mountain Brush Reference Area First -hit Allowable herbaceous cover X 2 = 24.8%
2010 Sagebrush Reference Area First -hit Allowable herbaceous cover X 2 = 89.5%
Calculation of 90 percent of the cover performance standard appropriate for 2010 sampling is
demonstrated below.
90 percent of the Cover Standard = 0.90 [0.83 X (24.8) + 0.17 X (89.5)] = 32.2%
The reclaimed (BRB) area sampled in 2010 at thirty locations to produce cover data applicable to
a potential Phase II bond release application exceeded 90% of the standard (32.2% allowable
cover). The figure for allowable cover in the 2010 Phase II BRB (37.5°/x) is the result of
subtracting tree, shrub and non - herbaceous cover (1.2 %) and perennial noxious weed cover
(0.44 %) and "excess annual /biennial cover' (0.5 %) from the observed all -hit total vegetation
cover of 39.6 %.
A one - sample t -test of the assertion that the 2010 Phase II BRB allowable cover is
indistinguishable from 90% of the standard is as follows:
t = ( 37.5 — 32.2) /(14.2 / sgrt 30) = 2.044
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