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Issue #3 — Lbs./ delav period <br />For the issue of pounds per delay period, I identified the specific holes that went off during both the 300 ms and 325 ms <br />time frame and added up the number of pounds of explosive that was recorded by the blasters in the field (this can also <br />be easily calculated based on depths and stem heights prior to loading). As you can see, the 300ms holes amount to <br />2,300# of explosives, while the 325ms holes amount to 2,460# of explosives. We knew that we were far below the <br />allowable maximum due to the scale distance formula, so we used the average for the shot to calculate the Lbs. /delay <br />period. A closer look at this specific shot shows that the 325ms holes are slightly deeper than the average that was <br />previously being calculated as you explained in your e-mail. <br />Currently we use a procedure where we check the pattern based on a hypothetical max depth, max pounds scenario. In <br />this way, we will find the deepest holes in the pattern, and multiply the pounds used in that hole by the max number of <br />holes shooting within a 8ms period as calculated in the aforementioned spreadsheet. Here we can be totally sure that <br />we are below the max pounds per 8ms delay period limit based on scaled distance requirements. <br />Using this method for the December 7th shot, the maximum pounds in one hole was 640. Multiplying this number by 6 <br />you find that the maximum possible pounds shooting within a 8ms period is 3,840. (not even half of the 7,950 limit for <br />this specific shot so further evaluation effort is not required). <br />We will also be using the same method with our electronic detonation system to ensure that the regulation <br />requirements are not exceeded. <br />This method of calculation will be done before the pattern timing is complete. In that way we can pick an initiation point <br />position that ensures that we will be safely below our scaled distance threshold. <br />Issue #4) — Direction and identification of nearest non -owned dwellin <br />Our plan for the future to ensure direction and identification of the closest non -owned building will be to modify our <br />blasting summary sheet to add a line to that sheet for identification and direction. We will also probably add lines for <br />Initiation System, Type and length of stemming as well as the type of delay detonators used. This information is being <br />put into the Notes section of the form, but as it is specifically called out in the regulations to be included, we will modify <br />the sheet to add spaces for them so someone does not inadvertently leave them off the summary sheet. This will be <br />accomplished in a forthcoming Technical Revision. <br />Hopefully this answers all of your questions concerning this particular blast, and our blasting program in general. Feel <br />free to contact me if you have furth r questions, <br />/homas Paulson <br />P.O. Box 187 <br />Craig, CO. 81626 <br />(970) 824 -4401 Ext. 466 <br />(970) 826 -6178 (Fax) <br />(970) 819 -6380 (Cell) <br />tom @trappermine.com <br />