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III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken during the inspection <br />and the facts or evidence supporting the enforcement action. <br />This was a partial inspection of the New Horizon Mine, conducted by Dan Mathews of the DMG Grand Junction <br />Field Office, 101 South 3rd, Suite 301, Grand Junction, CO 81501. Weather was clear and mild; approaching 60 <br />degrees bymid-afternoon. Ground surfaces were free of snow; moist to muddy due to recent melt. Ross Gubka <br />of W FC accompanied me on the inspection. <br />The primary focus of the inspection was to view an area tentatively proposed for use as an irrigated pasture <br />reference area, in lieu of the previously approved technical standard for irrigated pastureland. The area under <br />consideration is a gently sloping, approximately 8 acre fenced parcel located a short distance south of the mine <br />office on land owned by W FC. The parcel has been used for at least the last few years as a horse pasture. <br />Horses were fed hay in the SW corner of the parcel, and that area (maybe a half acre to an acre) is pretty beat <br />down from the concentrated tromping and grazing. The rest of the area looks to be in pretty fair shape, although <br />it was difficult to assess species composition and productivity in any detail due to the season and the fact that <br />the pasture was grazed down last growing season. The dominant cover is pasture type grasses, with minimal <br />presence of weedy species, and no evidence of noxious species. Operator indicated there are two primary soil <br />types represented; a shallower soil type in the northern 1/4 or so, and a deeper soil type over the remainder of <br />the area. There is a shallow Swale feature running more or less north to south through the parcel, with a narrow <br />band of cattails, sedges and other wetland obligates along the bottom of the Swale, a wider band of grasses <br />adapted to poorly drained soils (such as redtop) along the margins of the Swale, and typical irrigated pasture <br />grasses such as smooth brome, etc., in other areas. Slightly higher areas generally toward the north end of the <br />site appear to support a higher percentage of Kentucky bluegrass and wheatgrasses, adapted to somewhat drier <br />conditions, which may be reflective of shallower soil and/or irrigation water distribution patterns. <br />I suggested that it might be warranted to carve out the horse feedinglcompacted area at the south end and <br />exclude it from the reference area; Mr. Gubka disagreed, his contention being that heavy use areas like that <br />were pretty typical of irrigated pastureland in the vicinity. We will need to give this some thought and take <br />another look during the growing season, prior to sampling, when vegetative growth will allow for a more <br />complete assessment of site condition and species composition. Sampling should be done in June, timed so <br />that reclaimed area sampling to be conducted concurrently will be completed just prior to 1st cut harvest of the <br />reclaimed pasture fields. Statistically adequate cover and production sampling should be performed, with oven <br />dry production clipping results to be recorded and reported by life form; point intercept cover data to be recorded <br />by vegetative species (current year growth), litter, rock, or bare ground. <br />In general, the tentative reference site appears to be relatively representative of typical irrigated pasture areas in <br />the vicinity. An approach using vegetative cover and adjusted herbaceous production from the parcel may be <br />approvable. The "adjusted production" approach discussed with the operator would entail applying a multiplier <br />factor to the reference area production mean, prior to comparison with reclaimed area, based on acreage <br />weighted soil type composition within the reference area and the reclaimed block. Adjustment factors would be <br />applied to the various soil types within the reference area and within each reclamation block (determined from <br />the pre-mine Soils Map), based on relative production potential associated with each type (appropriate factors <br />for each soil type would be based on NRCS published documentation or written projections). The reference <br />area multiplier factor would be the ratio of reclaimed block acreage weighted adjustment factor to reference site <br />acreage weighted adjustment factor. For example, if acreage weighted adjustment factor of 1.1 was established <br />for the reference area, and acreage weighted adjustment factor of 0.9 was established for the reclamation block <br />(a Reclaim: Reference adjustment factor ratio of 0.8), the reference area production mean would be multiplied <br />by the ratio (0.8), prior to success comparison. <br />Operator will need to submit a technical revision application to incorporate the reference area, and the specific <br />comparison approaches proposed for irrigated pasture cover and production success demonstration, along with <br />sampling data and soil type production adjustment factor documentation following data collection later this year. <br />Narrative will need to confirm that management of the reference area will conform with 4.15.7(3)(d) and (f). <br />Various other permitting related revegetation issues were discussed, without definitive resolution <br />3 <br />