2018-04-25_PERMIT FILE - C1981038 ‎(3)‎

• Permit No: C1981038
• IBM Index Class Name: Permit File
• Doc Date: 4/25/2018
• Doc Name: VEGETATION INVENTORY PROPOSED PORTAL SITE
• Section_Exhibit Name: Volume 9A ENVIRONMENTAL RESOURCES - VEGETATION Appendix Part 2
• Media Type: D
• Archive: No

Volume 9A,Vegetation Tab,Hamer and Associates July 1986 Report
Average herbaceous production in the mixed shrub type was 247 lbs/acre
oven dry forage. Converting oven to air dry forage by a factor of 1.11 ,
yields 275 lbs/acre available herbaceous air dry forage. Assuming a 50 per
{ cent utilization factor and 900 lbs/acre cattle animal unit or 150 sheep
animal unit, the cattle carrying capacity was 0.15 AUM's per acre and sheep
carrying capacity was 0.9 AUM's per acre.
4.0 CONCLUSIONS
The vegetation at the Orchard Valley Mine is typical of the oakbrush
and mixed shrub types found throughout Delta County and are similar to types
studied for the 1983 permit.
4.1 Revegetation Success Standards
The approved revegetation success standard (1983 permit,Section 2.05.4
Revegetation Success ) for the Orchard Valley Mine stated that revegetation
was considered to be successful if:
The revegetation success standards in this section have been revised. Please see
Volume I Section 2.05.4(2)(e)(vii).
t
These standards were developed based upon literature surveys of
vegetation information from the Paonia area, data from local mines, data from
Soil Conservation Service range sites, and data from OVM reference areas.
The cover data presented for the vegetation types studied for the
proposed portal site is similar to the mixed shrub reference area cover which
was used in the development of the cover success standard. Comparing the
present data for the oakbrush and mixed shrub types with that presented for
the mixed shrub type in 1983 revealed that vegetation cover was 70.4, 68.5
and 75 percent respectively. Total cover (vegetation, rock and litter
combined) was 98.5, 88.7 and 96.0 respectively.
The production data presented for the vegetation types studied for the
proposed portal site is higher than the mixed shrub reference area production
data (45.5 lbs. per acre) but lower than the previously established success
standard of 400 lbs. per acre. Herbaceous production in the oakbrush and
mixed shrub vegetation types was 387 and 247 lbs, per acre, respectively.
The density data presented for the vegetation types studied greatly
exceeds the previously accepted success standard, however the standard
TR-63 6 01/18