2011-03-24_REPORT - C1981019 ‎(10)‎

• Permit No: C1981019
• IBM Index Class Name: Report
• Doc Date: 3/24/2011
• Doc Name: 2010 AHR & ARR Part 3
• From: Seneca Coal Company
• To: DRMS
• Annual Report Year: 2010
• Permit Index Doc Type: Hydrology Report
• Email Name: JHB
• Media Type: D
• Archive: No

2.2.3 EP040
EP040 is comprised of 10.3 acres of moderately
sloping revegetation. This unit was seeded in 2003,
making 2010 the seventh growing season. A
significant total of 41 plant taxa were observed in t' E 5 6 7
the unit, unfortunately two of them are noxious ( i
(Table AB-1). Current annual production across the y' i F, it 'x + p
unit averaged 1,616.3 pounds per acre in 2010 with
perennial grasses and perennial forbs the dominant s
categories (Table 1 and Chart 2). Ground cover in ?f' +,., +»
EP040 consisted of 45.6% live vegetation, 0.8% r
rock, 41.1% litter, and bare soil exposure of 12.7%.
Perennial cover across the unit averaged 32.6%. t''" +''
Dominant taxa were thickspike wheatgrass, ,R
cheatgrass, and streambank wheatgrass with 10.2%, J
7.1%, and 5.6% cover, respectively. Sub-dominant i20
species were basin wildrye, beardless bluebunch ;
wheatgrass (Agropyron spicatum inerme), and
crested wheatgrass (Agropyron cristatum) with ~ Y( '
3.6%, 3.2%, and 2.1% average cover, respectively. "`
CObtNV Mine - NeveuEt2ttrn Monhnrlno '?` a iMh oafs 175 !¢e[ Woody plant density was determined from 20 belt EP040
=?M
transects. Density (Table 3) totaled 22 young and
mature stems per acre with mountain snowberry (Symphoricarpos oreophi/us) the dominant woody plant.
With regard to diversity, EP040 exhibited six perennial grasses with between 3% and 50% relative cover
and relative forb cover of 16.1% (excluding noxious weeds).
This unit readily passes the production bond release criterion, but fails the cover comparison (Charts
1 and 2). Unit EP040 currently passes the diversity standard set forth by TR-72 (Charts 3 and 4). This
unit needs to have qualified shrub acres properly delineated, but given that there were only 22 shrubs
per acre identified in the woody plant density transects, expectations are that this unit will need to be
grouped with adjacent units to meet the woody plant density standard of 150 stems per acre on 3% of
the reclaimed land. Shrub patch delineations are slated for spring 2011. Noxious weeds are not yet a
problem, but there were two species, Canada thistle and musk thistle (Carduus nutans) that were
encountered during ground cover assessments (Table AB-2). Chemical application should be considered
for this unit to maintain control of the noxious weed population. Annual bromes are present with 7.5%
cover, down from 20.6% in 2007.
Unit EP040 exhibits good production and excellent diversity for seven-year old revegetation.
However, the cover values exhibited by this unit should be considered below average. Perennial cover
has decreased since 2007, but the relative cover by perennials has improved from 65.9% to 71.5%.
Indications are that this unit is still on an appropriate trajectory for bond release, but more time is
needed. Overall, Unit EP040 should be monitored again in 2013, but solutions for meeting the shrub
standard need to be discussed.
Cedar Creek Associates, inc. 16 Colowyo Mine
2010 Revegetation Monitoring Report