REV14769

• Permit No: C1981008
• IBM Index Class Name: Revision
• Doc Date: 12/27/2005
• Doc Name: Revegetation Plan Review Memo
• From: DTM
• To: MPB
• Type & Sequence: MT5
• Media Type: D
• Archive: No

Please give consideration to the concerns we have identified and the information
provided, and develop an amended, detailed irrigation schedule to be applied to
dryland pasture areas at New Horizon, with justification based on recommendation
from recognized authorities or applicable research for the irrigation plan proposed.
12. Table 2.05.4(2)(e)-3 acreage figures for various pre-mine and post-mine vegetation type
categories shows an increase in irrigated acreage of 77 acres fallowing reclamation.
Please address the question of whether sufficient irrigation water is available and
water rights sufficient to allow for the increasetl acreage of irrigated agricultural
(ands proposed.
13. On page 2.05.4(2)(e)-17, production standard of 1.84 tons per acre is specified for
irrigated havland. On page 2.05.4(2)(e)-20, a production standard of 1.50 tons per acre
is specified for irrigated pasture. Based on the estimates given by local farmers upon
which the standards are based, it would seem that the higher standard would more
specifically apply to irrigated alfalfa hayland, and the lower standard to irrigated grass
hayland or irrigated pasture. Please address this minor discrepancy, and amend the
narrative as appropriate.
14. The production sampling procedure described in Item 4 on pages 2.05.4(2)(e)-18 ,20,
and 24 "...air dried for 96 hours to simulate field hay drying..." would seem to lack
desirable precision, given the extent to which temperature and humidity could impact the
samples. Oven drying to a constant weight as described in Section 2.04.10 of the
application with respect to baseline data collection, is recommended. Please address
this concern and amend the items as appropriate.
15. The sample adequacy formula listed in Item 5 on pages 18, 20, and 22 is a formula listed
in the 1995 DMG guidelines. This formula is more stringent than required by rule
changes recently approved by the Mined Land Reclamation Board. Please review the
methods applicable to demonstrations of sample adequacy and revegetation
success for cover and productivity in Rule 4.15,11(2), and amend the items as
appropriate.
16. In Item 6 on pages 18 and 20, an optional total harvest production measurement
approach is referenced. Please provide additional detail on the method to be used
to quantify production per acre using the total harvest method. Please refer to the
methodology descriptions provided for baseline total harvest documentation on
pages 2.04.10-19 and 2.04.10-23, and provide comparable detail. Note that the total
harvest method would entail direct comparison of the reclaimed area production to
90% of the standard, with no allowance for a statistical confidence interval.
17. Design approaches and methods for sampling of vegetation cover, and statistical
comparisons for statistically valid demonstrations of success for cover, with respect to
irrigated pasture and dryland pasture reclamation areas, are not specifically addressed in
the application. Please amend the text to include plans addressing cover sampling
and statistically valid demonstrations of success for cover, in compliance with
Rules 4.15.7{2){b) and (c) and 4.15.11. The reference to use of procedures in the
1995 Guidelines document, on page 25 should be deleted, as certain information in
that document, including sample adequacy formulas and hypothesis testing
approaches, is now outdated.
18. The mid-summer sampling timeframe mentioned may be overly restrictive; a June
through September sampling window would allow sufficient flexibility to coordinate
sampling with growing conditions in a given year. Please consider amending the
narrative as appropriate.