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7/28/2014 <br />k V3� <br />Ar �Ii'i� '51x. STATEOF <br />• ■ • ■ • <br />:v�7u <br />State.co.us E>Lcutive Branch Mail - Blasting Records for Trapper Mine <br />Blasting Records for Trapper Mine <br />Talvitie - DNR, Marcia <marcia.talvitie @state.co.us> Mon, Jul 28, 2014 at 11:57 AM <br />To: "Forrest V. Luke" <forrest @trappermine.com> <br />Cc: "Ebert, Jared" <jared.ebert @state.co.us> <br />Good morning, Forrest <br />Thank you for escorting me during my inspection of the Trapper Mine on July 22nd. Following our time in the <br />field, I collected photocopies of a few Blasting Summary sheets (Dec. 2 and 7, 2013 and Jun. 2 and 3, 2014). <br />In my efforts to evaluate the records for compliance with our rules, specifically 4.08.5 - Records of Blasting, <br />I've come up with some questions that I am unable to answer with certainty. <br />TMI's Blasting program is described in Section 3.4 of the permit. To determine Peak Particle Velocity (PPV), <br />Scaled - Distance factors are used as described on Page 3 -32. Information that will be included in the blasting <br />records is presented in Subsection 3.4,4 beginning on Page 3 -32, and is found to be consistent with the <br />requirements of Rule 4.08.5. <br />The record for each Shot consists of a Summary form; a layout sketch; and a table providing the depth of each <br />hole, the water level, the drilled depth, and pounds of explosives used. The form provides places in which to <br />enter all of the data required by Rule 4.08.5, with the exception of (4) Identification of and direction to the <br />nearest building. None of the records I reviewed appear to involve "decking" of the shot; the method for <br />recording those details is unknown. <br />My questions relate to TMI's means of determining what numbers are reported in certain blanks on the cover <br />form. My understanding, based on my review of the data available, is outlined below. I may or may not be <br />accurate in my assumptions or conclusions, so I would like to request that TMI review my analysis and provide <br />feedback - confirming and /or correcting. <br />For the sake of simplicity, I will discuss only the Dec. 7, 2013 shot, a full copy of which is provided as the first <br />attachment to this Email. <br />1) Bulk Lb. (21,990 #) and Slurry (13,040 #) weights from the drill hole table are added up, and entered into the <br />"Materials Used" portion of the Summary form. These weights are then combined and entered as "Total <br />Explosives" (35,030 #) in the "Blast Summary" section at the bottom of the page. <br />2) The number of "Holes Shot" (91) and "Total Depth" (2364') are also entered under the Blast Summary. An <br />"Ave. Depth" (26) is calculated by dividing Total Depth by # of Holes. <br />,/0 <br />3) The "Total Delays" (911 is derived by summing the Delays listed under the "Materials Used" section <br />(91 +1-10). <br />4) I am not sure how the "Delay Periods" entry (15) is determined, nor by whom. <br />5) It appears that the Holes /Delay Period (6) is a calculated by dividing "Holes Shot" by the "Delay Periods ". <br />https:llmail.g oog l e.corrymai llu10/? ui= 2 &ii- 9la975f658 &'Aevr—pt&search= sent &th= 1477ele4bfb858c@&si ml= 1477ele4bfb858ca 1/3 <br />