GENERAL51833

• Permit No: C1981047
• IBM Index Class Name: General Documents
• Doc Date: 7/25/2007
• Doc Name: Year 9 Vegetation Report Adequacy Review Letter
• From: DRMS
• To: MINREC, Inc
• Permit Index Doc Type: Vegetation
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman St., Room 215
Colorado 80203
Denver C O L O R A D O
, D I V I S I O N O F
Phone: [phone] RECIaMArION
FAX: [phone] M I N I N G
- &-
July 25, 2007 SAFETY
Bill Ritter, lr.
Governor
Jim Stover, P.E.
MINREC
InC Harris D. Sherman
,
. Executive Director
P.O. Box 60340 Ronald w. catlany
Grand Junction, Colorado 81506 Division Director
Natural Resource Trustee
RE: Blue Ribbon Mine, PetmitNo. C-1981-047, MINREC, Inc.
Year 9 Vegetation Report, Adequacy Review
Dear Mr. Stover:
The Colorado Division of Reclamation, Mining and Safety (Division) has finished its adequacy review of
the report Phase III Bond Release Evaluation-Year 1 of 2 (2006 Revegetation Success Evaluation, Blue
Ribbon Mine), prepared by Cedaz Creek Associates, Inc., dated March, 2007 for the Blue Ribbon Mine.
This is an excellent report with sampling methods and statistical procedures clearly documented. Data and
analyses are properly presented in tables, supported by narrative discussion, charts, and photographs.
Sampling protocol and statistical procedures were in conformance with permit requirements. Year I
success was demonstrated for all parameters. Cover and production success was demonstrated for both
revegetated communities (grassland and riparian) using the stringent "reverse null", one sample t-test.
Sample adequacy was demonstrated for each community and each parameter, in both reclaimed and
reference areas (as such, t-testing was actually not necessary to demonstrate success).
Year 1 diversity success was properly demonstrated for each community.
Woody Plant density success demonstrations appear to conform to the approved permit
requirements, but do not fully comply with applicable requirements of Rule 4.15.11, which became
effective in November of 2005, after the sampling and statistical evaluation TR plan was approved,
but before the sampling was conducted.
For the grassland community, the approved plan allowed for a complete census count, as an alternative to
sampling, using a well defined protocol to ensure an accurate count. The census method is more stringent
than sampling methods specified in the regulations; any error in counting is more likely to result in "under-
count" than "over-count". Year I census results in the grassland community indicated 258 woody stems
per acre, compared to the success standard of 90 stems per acre. Although the regulations do not
speciTically address the total census method, it is actually more precise than sampling. Therefore,
the Division accepts the census as a valid demonstration of success for the small grassland area
woody stem density standard.
For the riparian community, proper sampling procedures were used, and results clearly document that
woody stem density in the reclaimed area exceeds the approved standard (reclaimed area sample mean of
8,175 stems per acre vs. standard of 900 stems per acre.) Cedar Creek used a reverse null t-test to
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