2013-04-05_PERMIT FILE - C1981019 (10)

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RULE 2 PERMITS General Blasting Procedures Colowyo gives warning and all -clear signals of different character that are audible within a range of one - half mile from the point of the blast. Persons working within the permit area and each person who resides or regularly works within one -half mile from the blast area will be informed of the meaning of the signals through appropriate instructions. Access to the immediate area of the blasting site will be cleared and controlled by qualified mine personnel prior to any blast. Colowyo also maintains signs in accordance with 4.02.6. All areas subject to blasting are fenced for livestock. To protect the public, Colowyo will regulate access to any area possibly subject to flyrock from blasting within the permit area. The mine area will be identified by signs on all access roads restricting entry to unauthorized personnel. Signs identifying the area as a blasting area will describe the warning and all - clear signals. Four series of three short sirens and four series of three long sirens will be sounded before the blast. After checking the blast, the Blasting Foreman will report all clear to the barricade crews. Colowyo will use the explosive equation of 4.08.4 (10)(c)(i) to limit the pounds of explosive per 8ms period, similar to that shown on the Blasting Analysis Map (Map 26). Some previous seismographic measurements were made during blasting operations at Colowyo; the results are set forth in Exhibit 14 - Seismographic Measurements. Although seismographic measurements have been made in the past seismographic records will not be used to demonstrate compliance with maximum peak particle velocities. Colowyo has chosen to continue the use of the - scaled- distance formula in Rule 4.08.4(10) (c) (i) to demonstrate compliance with ground vibration requirements. Colowyo will conduct airblast monitoring to ensure compliance with airblast standards. All blast events will be monitored for airblast. On these reports Colowyo will record the name of the company doing the monitoring, the person taking the periodic airblast reading, the name of the person analyzing periodic airblast records, and the distance of the instrument from the blast. Airblast monitoring will be taken from the closest dwelling to the blast area. An Instantel Inc. Blastmate Series II , model DS-477 are maintained at the Durham Ranch and Wilson Creek resident area. Details regarding the monitor specifications are included in Exhibit 14. Airblast monitoring will be recorded on a seismograph report (See Figure 2.05 -4) for review by in -house personnel, agency representatives, and requesting publics. The airblast data is recorded under the "PSPL" (Peak Sound Pressure Levels) in decibels (dB). Additional information concerning the use of explosives is found in Section 4.08. Disposal of Excess Spoil As discussed under the heading of Production Methods and Equipment in Section 2.05.3, Colowyo has constructed an overburden disposal structure known as Streeter Fill. During the early operation, overburden had to be placed into the Streeter Fill so that sufficient working area could be developed prior to the placement of subsequent overburden into the mined -out areas. Additional information concerning the Streeter Fill is set forth in Exhibit 12, Experimental Practice Information. In the initial five year permit term, the Streeter Fill was permitted as an Experimental Practice. In 1986, the Experimental Practice designation was terminated. However, in the interest of continuity, information regarding Streeter Fill is still located in the Experimental Practice Section. Rule 2 Permits 2.05 -15 Revision Date: 6/11/12 Revision No.: RN -06