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water deficit in June, about 20 percent of the annual moisture deficit for the plant could be • obtained during these periods. In conclusion, improved and native grasses are only marginally subirrigated along Fislt Creek on the T2 terrace. Obviously, plants on higher terrace levels where the separation of the roots and the capillary zone increases, do not derive an important part of llte soil water deficit from shallow groundwater and are therefore no subirrigated. Please refer to Map 5 for a delineation of the areas considered to be subirrigated in the Fish Creek valley. Tributaries to Fish Creek The northern tributary was evaluated in the field, and using the color infrared photography for indicator of subirrigation to agriculturally useful species. The color infrared photography showed a bright red reflectance for one of the small tributaries to this drainage and also a light red blush on the lower terrace in the vicinity of the confluence with the previously mentioned bright red reflectance tributary. In the field these areas were confirmed to be wet and spongy. The primary species of plants present throughout the we[ areas were sedges. These plants are not considered desirable for grazing purposes. Therefore, although this area was subirrigated it would not support subirrigated agricultural activities (i.e., it is too wet). Considering that water is not available for flood irrigation (Section Ill) or subirrigation agricultural activities, this drainage is concluded to no[ be an AVF and is omitted from further discussion. SECTION IV ALLUVIAL VALLEY FLOOR DETERMINATIONS [3ased on the alluvial valley floor (AVF) regulations of the Colorado Mined Land Reclamation board and the Office of Surface Mining's AVF Identification and Study Guidelines, portions of the study area associated with the proposed Fish Creek Mine meet the criteria for designation as AVF's Tltis section of the report specifically identifies which areas qualify as AVF's in the study area and identifies the essential hydrologic functions associated with each designated AVF. (Please refer to the previous sections of this report and associated maps which provide more detailed evaluations of the valleys in the study area in terms of the geomorphic and water availability criteria for AVF designation). Fislt Creek The valley of Fish Creek in the study area is determined to be an AVF. The extent of the Fish Creek AVF includes the Tl, Tz, and T3 terrace areas (See Map 1). This AVF has the essential hydrologic function of active flood irrigation, potential flood irrigation, and subirrigation. It should be noted that the TI and Tz terraces associated with Fish Creek are considered [o be marginally subirrigated and that the T3 terrace is not considered to be subirrigated. SECTION V SIGNIFICANCE DETERMINATION . Section lV of this report includes a discussion concluding that the Fish Creek valley is an AVF. The followuig analysis delineates Itow agricultural production on the actively irrigated or I:environ\tracy\document/ExhibTA 9 OI/IG/9S