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Construction of the loadout pad and haul/access road within the permit area has disturbed <br />approximately 13 acres, primarily orchard land. Surface disturbances have been limited to the <br />colluvial deposit, with no surface disturbance in the present flood plain. No further surface <br />disturbance is proposed. <br />The application describes the unconsolidated deposit as being composed of colluvial material <br />resulting from mass wasting and slope wash from the steep slopes rising to the north of the <br />permit area (see Map 11). The text indicates that, since settlement in the early 1900's, the area <br />was graded to allow construction of the Fire Mountain Canal and accommodate flood <br />irrigation. <br />The affected area occupies a transitional area (mapped as Qc on Map 2 of the application) <br />between the flood plain and terrace complex below (mapped as Qa on Map 11 of the <br />application) and the steeper upland slopes to the north of the permit area. It is the Division's <br />opinion that this transitional area is more appropriately considered to be an upland area rather <br />than part of the flood plain and terrace complex as defined in sections 1.04(10), (142) and <br />(147) of the Rules and Regulations. <br />Although colluvial deposits can be considered to be part of unconsolidated alluvial deposits in <br />many cases, in this particular instance the deposits are fairly deep and appear to be underlain <br />by bedrock or other fairly consolidated material (on the basis of test pits and observation by <br />Division personnel). The permit area is also on a moderately steep slope (15%) which the <br />applicant suggests was previously graded to accommodate agricultural activity. The type of <br />irrigation practiced on these colluvial deposits consists of diverting the flow from a nearby <br />irrigation canal into a system of furrows. This type of irrigation is the only feasible practice <br />under such steep slope constraints and is considered to be artificial subirrigation rather than <br />flood irrigation as strictly defined in Rule 1.04 (48). <br />Based on these considerations of the nature of the material, steepness of slopes and irrigation <br />practice the Division finds that the permit area is more appropriately considered to be within <br />the upland area relative to the alluvial valley floor, and is not within the flood plain and <br />terrace complex. The Division therefore makes a negative determination for the presence of <br />alluvial valley floors in the specific area of proposed disturbance for the Terror Creek <br />operation. <br />The valley bottom below the proposed disturbance (below the existing railroad grade) is <br />considered to be an alluvial valley floor. The Division therefore has to make the required <br />findings for the impact of the disturbance on an adjacent alluvial valley floor. These findings <br />are presented below. <br />B. Alluvial Valley Floor Findings <br />Pursuant to Rules 2.06.8 and 4.24.2, the Division is required to make specific written findings <br />on the effect of mining upon any AV F's within the permit and adjacent area. The findings for <br />the North Fork AVF are presented below. Mining activity (construction of the loadout <br />facility) has already disturbed approximately 13 acres of land on the colluvial slope. No <br />further surface disturbance is proposed by the applicant. <br />I . Pursuant to Rule 2.06.8(5)(a)(i)(A)(I), the Division finds that the surface coal mining <br />operations would not interrupt, discontinue, or preclude farming on the alluvial valley <br />floor. Loadout operations on the colluvial slope will not physically impact farming <br />operations on the alluvial flood plain below. Groundwater is not present in the <br />18