2017-02-28_REPORT - C1981028 ‎(30)‎

• Permit No: C1981028
• IBM Index Class Name: Report
• Doc Date: 2/28/2017
• Doc Name: Annual Reclamation Report
• From: Coors Energy Company
• To: DRMS
• Annual Report Year: 2016
• Permit Index Doc Type: Annual Reclamation Report
• Email Name: RAR
• Email Name: DIH
• Media Type: D
• Archive: No

Keenesburg Mine 2016 Vegetation Monitoring Report
Z2 Herbaceous Production
Based on the results of the herbaceous production sampling, four of five Reclamation Areas
exceeded the production success standard calculated value (Table 19). However, Reclamation
Area 31 fell short.
Table 19: Herbaceous Production Success Standard Comparison
Herbaceous Production
(g/m2)
Reclamation Area
23
25
29
30
31
Mean
215.9
185.5
236.7
270.7
140.2
Mean (minus noxious)
209.3
179.6
229.6
258.7
109.2
St Dev (minus noxious)
98.5
64.8
146.6
176.7
42.2
N
5
15
15
15
15
Nmin
52
24
74
1 84
27
Standard
186.9
90% of Standard
168.2
Standard Passed?
Yes
Yes
Yes
I Yes
No
Herbaceous production increased substantially in all four Reclamation Areas that were
monitored in 2015 and these increases were most pronounced in the perennial grass species
(Figure 9). In 2012, perennial grasses comprised 95-100% of the herbaceous production in each
of these areas. However, by 2015, not only has the overall production decreased, but perennial
grasses contributed less than 50% in Reclamation Areas 23, 29, and 30. In 2016, perennial
grasses were back to their 2012 production levels as well as being considerable higher overall.
The large increase in annual introduced forbs (primarily prickly lettuce) was the primary
difference between the 2012 and 2016 data.
The reasons for the increase in production are likely the same as those postulated above
regarding vegetation cover. Three years of above average precipitation has allowed these
Reclamation Areas to recover from the drought they experienced in 2012 and 2013. Further, the
timing of the precipitation in 2016 with consistently above average precipitation every month
from March through June and a spike in July (225% of average) gave the annual species a boost
that likely allowed them to persist into the growing season longer than usual. Often the cool
season annual species have already completed their life cycle by the time monitoring occurs in
August and do not contribute as much to the production data.
Habitat Management, Inc. 28 October 2016