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In 1999, estimates of mean cover in 2 subjectively selected irrigated pastures (deemed <br />representative of "typical' conditions) were also similar, showing perennial grass cover of 44.5 %, <br />perennial forb cover of 33.3 %, and total desirable vegetation cover of about 79 %. Annual <br />herbaceous production was estimated at 4,153 lb/acre. The 1999 mean is higher than the 2007 <br />mean measured in the reference area, but the irrigated pasture type has been demonstrated in <br />1987 and 1999 sampling to be extremely variable in production depending on site factors, <br />management, and maintenance. <br />Irrigated Pasture Success Standards <br />Jim Boyd, the local NRCS representative, reviewed the capability of all soils in the reference area <br />and in the reclaimed area and assigned a relative factor to each of these soils. This letter is <br />included in this subsection. As can be seen from the letter, some soils are more productive than <br />others. The table below shows how the weighted average for the reference area is calculated. The <br />soil types are based on the USDA - NRCS Soil Survey of San Miguel Area, which was compiled <br />in the field from 1978 to 1984. The report was published in 1986. This survey can be obtained on <br />the internet at http:// offices. usda. gov /scripts/ndISAPI.dll/oip _public /USA map. <br />In order to further account for differences in soils in the mine reclaimed areas compared to the <br />reference area, a soil productivity factor has been developed by the local representative of the <br />NRCS which makes adjustments to the required levels of production based on the weighted <br />average of these factors in the reclaimed area compared to the reference area. <br />The table below shows how the weighted average for production from the reference area is <br />calculated. <br />Revised April /09 TR58 2.05.4(2)(e) -19H <br />- rR - 58 <br />3'1qayzo0 <br />