2013-12-10_PERMIT FILE - C1981018A (3)

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As noted on the design drawings of the Scullion Gulch bypass system, erosion protection is provided at the inlets and outlets, as appropriate. Concrete hardwalls are provided at all inlets, while inlet and outlet channels and banks are riprapped. Debris - control structures are provided at all inlets to prevent clogging. It was assumed that the flow in all lateral culverts entering the main Scullion Gulch bypass culvert would be controlled at the inlet. This assumption was based on the steep slope of all lateral culverts. As a result, the culvert design nomographs of Hydraulic Engineer Circular No. 5 of the Federal Highway Administration were used to determine proper sizing of all laterals. In each case, an allowable headwater depth of 1.2D was assumed (where D is the diameter of the culvert). The streams are not perennial and do not support an aquatic community. Therefore, the requirements of Section 4.05.1 S do not apply. V.D Storage and Disposal of Acid - Forming, Toxic - Forming and Combustible Materials The mine development and coal processing wastes do not have properties that classify them as acid forming or toxic forming (see Table V -1). The percentage of combustible material in the waste is small. The waste material is placed and compacted to reduce the possibility of spontaneous combustion (see Section IV.D.3). If large amounts of combustible materials are delivered to the disposal area, special measures such as windrowing the material and mixing it with noncombustible material will be taken to avoid having large pockets of the combustible material within the waste bank. Gasoline, diesel fuel, and bulk oil are stored in tanks placed in properly sized secondary containment structure designed to contain precipitation plus the contents of the largest tank (Map 15 and 155). No more than 1,000 pounds of explosives are expected to be stored in the explosive storage magazine. In accordance with the American Table of Distances for Storage of Explosives, the magazines are located approximately 650 feet from buildings or work areas and are located behind a natural (rock) barrier wall. Primers and explosives are stored in separate structures. These structures comply with the National Fire Code (NFC) requirements for Type 1 magazines. Storage and handling are in accordance with NFC and other applicable regulations. Toxic - forming, acid - forming, and combustible wastes (such as fuel oil, grease buckets, old tires, etc.) are collected and stored in suitable containers in accordance with NFC and other applicable regulations. A contractor collects this material on a regular basis and is responsible for its proper disposal. Technical Revision #64 (4/2007) V -16