2011-08-04_ENFORCEMENT - C1981008 ‎(4)‎

• Permit No: C1981008
• IBM Index Class Name: ENFORCEMENT
• Doc Date: 8/4/2011
• Doc Name: OSM Technical Review of PR6 Prime Farmland Yield - Morgan Property
• From: OSM
• To: DRMS
• Email Name: SB1
• Email Name: DAB
• Email Name: MLT
• Media Type: D
• Archive: No

Appendix B
OSM Review of Colorado Permit C- 008 -81
Permit Language Related to Prime Farmland Yields
Section 2.06.6 of the permit essentially (in Table 2.06.6 -1) summarizes the locations in the permit of
the various responses to the requirements of Rule 2.06.6.
Page 2.04.10 -1 of the permit notes that the Morgan Property south of BB Road was studied in both
1987 (subsection 5) and 1999 (subsection 6).
Section 2.04.10, subsections 5 (Vegetation Baseline Sampling Results and Discussion - 1987) and
subsection 6 (Vegetation Baseline Sampling Results and Discussion - 1999), on pages 2.04.10 -26 and
2.04.10 -54 of the permit, respectively, state, `In 2008 NRCS designated certain soils as prime
farmland soils. This led to the redesig,nation of Irrigated Pasture Hayland (IH) on the Morgan
property being redesignated as Cropland - Irrigated Hay (IC)."
The revegetation section, 2.05.4(2)(e) (page 4) of the permit states Irrigated Cropland, "areas will
have 100% alfalfa (not including a companion crop) which are well - managed, irrigated consistently
and harvested. See discussion in Section 2.04.9 on Prime Farmlands and Prime Farmland Soils."
Section 2.05.4(2)(e) subsection 5 (Revegetation - Irrigated Cropland), page 2.05.4(2)(e) - 39 states,
"these lands are the entire Morgan property of 107.96 acres...the species planted will be dominated
by alfalfa, as desired by the landowner, Morgans and that, "All lands restored to Irrigated
Cropland will meet the Prime Farmland requirement under Rule 2.06.6."
The permit on page 2.05.4(2)(e) - 45 states, "During the 1999 baseline vegetation survey (Sec.
2.04.10) the average yield for all pastures was 2.00 tons /acre. The yield ranged from a high of 4.26
tons /acre for highly managed alfalfa to a low of .57 tons /acre for unirrigated grassland." The
permit goes on to note that, "1999 was a very wet year in western Colorado (177% of normal...)."
The permit discusses irrigated cropland baseline data collected in 1987 in section 2.04.10. subsection
5.6 beginning on page 2.04.10 -49. Pages 2.04.10 -50 and 51 of the permit state:
"... Since no cropland was placed in production or harvested during 1987, no specc yield data is
available for the study area... For the Barx series map unit 70B the more extensive of the two series
cropped the following values might be achieved under a high level of management
(irrigated)... alfalfa hay — 5.5 tons /acre, grass hay — 4.5 tons /acre... For the Progresso series (map
unit 30C), the following values may be attainable under a high level of management
(irrigated):...alfalfa — 5 tons /ac ... Interviews during 1987 with the operator... indicated that the
actual yields are much lower... Observations of the condition of these cropland fields during 1987
support the contention that these lands receive only an average level of management at best."
OSM notes, the yield estimates presented above based on prime or prime -like soils comports
with the NRCS 4 April 2011 yield estimates for irrigated alfalfa.
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