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the values of the Scaled Distance Factor derived from these new plots are 28.26 <br />(from the combined data from Shot Numbers 2 and 3), and 34.85 (for the data <br />from Shot Number 1). <br />The Division understands the permittee's comment that by plotting these two <br />new analyses separate from the first regression analysis, the number of data <br />points in the new analyses appear too few to allow the new analyses to be <br />considered statistically valid. However, the Division believes that the high <br />values for the Correlation Coefficient for the two new plots provide enough <br />support to their validity that the Division cannot ignore these results. <br />Additionally, plotting the Shot Number 1 data separately did somewhat support <br />the Division's initial concern that a Scaled Distance Factor for a Peak Particle <br />Velocity value of 1.0 inches per second might be higher than 28.44 if the Shot <br />Number 1 data were analyzed separately from the other data points, as it <br />appeared in the first regression analysis that several of the data points in the <br />first analysis that were from Shot Number 1 were near, if not over, the 95% <br />conFidence level line. <br />The Division believes that the regression analyses provided by Matheson <br />Mining Consultants, Inc have adequately demonstrated that, for the Seneca <br />Coal Company's Yoast Mine, some level of variance from the Scaled Distance <br />Factors of Rule 4.08.4(10) is warranted. The Division, when considering <br />granting such a variance, must ensure that decisions regarding variances from <br />these criteria will be in the best interest of the owners of the structures listed in <br />this Rule. <br />Based upon the indications and results of the regression analysis of the data <br />from Shot Number 1, the Division therefore believes that a Scaled Distance <br />Factor of 35, for distances of 301 feet to 5000 feet between the structures <br />identified in Rule 4.08.4(10) and the nearest blast hole, is appropriate. Please <br />submit revised text pages to reflect this. <br />6. Response to Adequacy Question #6 <br />CMLRB Rule 4.08.4(10) lists three Scaled Distance Factors. One is used when blasting is <br />within 300 feet of [he protected structures, another when blasting is within 301 to 5000 fee[ <br />of the structures, and a third when blasting is over 5000 feet from the structures. In our <br />12/28/01 adequacy letter, we asked Seneca Coal Company if their proposed Scaled Distance <br />Factor would be applicable for all these distances. <br />In its I/l5/02 response, [he permittee modified its original proposal. The permittee now <br />proposes to use 28.44 (the value from it first regression analysis) for distances of 301 to <br />5000 feet between structures and blasting, but then proposes six tables (new Appendices V <br />and VI) that list [he charge weights versus actual distances for distances between ]0 and 300 <br />feet, and for distances greater than 5000 feet. <br />