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III. COMMENTS -COMPLIANCE Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. • Sampling and analytical procedures and sample design approaches will need to be described in detail in the bond release application(s). Bond release maps will need to clearly delineate the phased bond release blocks and the dryland pasture and irrigated pasture parcels, with numbered transect and quadrat locations depicted. Prooosed Irrigated Pasture Reference Area The area proposed for use as an irrigated pasture reference area was observed. The area was previously observed during my inspection of February 7, 2007 and is described in the February 9, 2007 inspection report. Site characteristics are generally as described in that report, with the notable difference that vegetative growth has substantially matured during the intervening months. The site appears to be representative of the more productive irrigated grass pastures in the mine vicinity. WFC agreed to remove a small area in the southwest corner of the 8 acre parcel that was beat down and weedy due to past horse feeding in that location, and placed temporary markers during the inspection to delineate the modified boundary. Species composition is generally as described in the February report, with productive pasture grasses including smooth brome, meadow fescue, timothy, and orchard grass present in the irrigated but well drained areas, sedges, rushes and tufted hair grass in the low lying poorly drained areas, western wheatgrass and other wheatgrasses in dryer areas. Kentucky bluegrass was present throughout the site, with the exception of the poorly drained areas. Statistically adequate cover and production sampling will be conducted within the next few days. Oven dry production clipping results for current year's growth will be recorded and reported by life form; point intercept cover data will be recorded by vegetative species, litter, rock, or bare ground. An approach using vegetative cover and adjusted herbaceous production from the reference site as the success criteria has been discussed with the operator. The "adjusted production' approach would entail applying a multiplier factor to the reference area production mean, prior to comparison with reclaimed area, based on acreage weighted soil type composition within the reference area and the reclaimed block. This adjustment factor approach is felt to be warranted, to provide for equitable comparison of reference area production to reclaimed area production, in situations where pre-mine soil types exhibited higher or lower production potential than the reference area soil types. NRCS written estimates for relative irrigated yield potential for each soil type would be provided, allowing for an acreage weighted relative yield projection for the reference area and each reclaimed block. If a particular reclaimed block has a relative yield projection that is 0.8x the reference area relative yield projection, then the bond release standard for the block would be (90% of) [0.8 x the reference area production mean]. In the event that t-testing is necessary to demonstrate success, the sample standard deviation would need to be adjusted by the multiplier as well (0.8 in this example). As noted previously, WFC will need to submit a technical revision application to incorporate the reference area, including the specific comparison approaches proposed for irrigated pasture cover and production success demonstration, along with sampling data and soil type production adjustment factor documentation. The application will need to include narrative addressing how the reference area will be managed in conformance with 4.15.7(3)(c) through (f). Revegetated Area Observations A 6.3 acre irrigated pasture area in the NH-1 mine block that had been tentatively considered for inclusion in the Phase 3 bond release application was observed. The pasture had obviously been grazed by cattle earlier in the growing season and appeared to have been minimally irrigated. It was apparent that ground cover and production were significantly lower than areas of similar age within the NH-2 mine block, that had not been grazed and had been irrigated more frequently during the growing season. It was agreed among the parties present that the NH-1 irrigated area would not be sampled this year for inclusion in a Phase 3 bond release application. The area was previously approved for 4