2001-12-11_PERMIT FILE - C1981038A

• Permit No: C1981038A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: VEGETATION INVENTORY PROPOSED PORTAL SITE
• Section_Exhibit Name: Volume 9A ENVIRONMENTAL RESOURCES - VEGETATION Appendix Part 2
• Media Type: D
• Archive: Yes

Average herbaceous production in the
oven dry forage. Converting oven to air
yields 275 lbs/acre available herbaceous
cent utilization factor and 900 lbs/acre
animal unit, the cattle carrying capacity
carrying capacity was 0.9 AU ht's per acre.
mixed shrub type was 247 lbs/acre
dry forage by a factor of 1.11,
iir dry forage. Assuming a 50 per
cattle animal unit or 150 sheep
was 0.15 AU M's per acre and sheep
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:
1) total vegetation ground cover exceeded 40 percent.
2)totalabove ground herbaceous production exceeded4001bsper
acre. ~
3) shrub density ranges between 800 and 1000 stems per acre
4) there are at least five native perennial herbaceous species
(four native, cool season grasses and one native forb) which
have a relative cover or production equal to or greater than 3%
each.
5) there are at least two native shrub species, neither of which
exceeds a relative density of 80%.
6) the five herbaceous species will not exceed 90% in relative
cover or production, and any one of the five species will not
exceed 60% in relative importance.
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