GENERAL36874 - Laserfiche WebLink

Home Browse Search

The affected area occupies a transitional area (mapped as Qc on Map 2 of the application) between the flood plain and terrace complex below (mapped as Qa on Map 11 of the application) and the steeper upland slopee to the north of the permit area. It is the Division's opinion that this transitional area ie more appropriately considered to be an upland area rather than part of the flood plain and terrace complex as defined in sections 1.04(10), (142) and (147) of the Rules and Regulations. Although colluvial deposits can be considered to be part of unconsolidated alluvial deposits in many cases, in this particular instance the deposits are fairly deep and appear to be underlain by bedrock or other fairly consolidated material (on the basis of test pits and observation by Division personnel). The proposed permit area is also on a moderately steep elope (15 g) which the applicant suggests was previously graded to accommodate agricultural activity. The type of irrigation practiced on these colluvial deposits consists of diverting the flow from a nearby irrigation canal into a system of furrows. This type of irrigation is the only feasible practice under such steep slope constraints and is considered to be artificial subirrigation rather than flood irrigation ae strictly defined in Rule 1.04 (48). Based on these considerations of the nature of the material, steepness of slopes and irrigation practice the Division finds that the permit area is sore appropriately considered to be within the upland area relative to the alluvial valley floor, and is not within the flood plain and terrace complex. The Division therefore makes a negative determination for the presence of alluvial valley floors in the specific area of proposed disturbance for the Terror Creek operation. The valley bottom below the proposed disturbance (below the existing railroad grade) is considered to be an alluvial valley floor. The Division therefore has to make the required findings for the impact of the disturbance on an adjacent alluvial valley floor. These findings are presented below. Alluvial Valley Floor Findings Pursuant to Rules 2.06.8 and 4.24.2, the Division ie required to make specific written findings on the effect of mining upon any AVF's within the permit and adjacent area. The findings for the North Fork AVF are presented below. Mining activity (construction of the loadout facility) has already disturbed approximately 13 acres of land on the colluvial slope. No further surface disturbance is proposed by the applicant. Pursuant to Rule 2.06.8 (5)(a)(i)(A)(I), the Division finds that the surface coal mining operations would not interrupt, discontinue, or preclude farming on the alluvial valley floor. Loadout operations on the colluvial slope will not physically impact farming operations on the alluvial flood plain below. Groundwater ie not present in the colluvium in the permit area and surface water from above will be diverted around the disturbed area. No future impact which might interrupt, discontinue, or preclude farming on the flood plain is proposed. Thus operations at Terror Creek would not interrupt, discontinue, or preclude farming on previously-undisturbed portions of the alluvial valley floor. Pursuant to Rule 2.06.8 (5) (a) (i) (A) (II) , the Division finds that the surface coal mining operations would not materially damage the quality and quantity of water in surface and underground Terror Creek Loadout Page 17