Laserfiche WebLink
'.~ - <br />Memo to Susan McCannon <br />Tatum Letter of May 11, 1995 <br />page 2 <br />structure's symptoms suggested to me... I prefaced my comments regarding <br />my preliminary summary of observations regarding the condition of the <br />Tatum structure with generic comments regarding mine subsidence. During <br />that discussion I referred to the angle of draw. I recall stating that, while t <br />did not specifically remember the Golden Eagle mine's subsidence <br />parameters, angles of draw determined for Colorado underground coal mines <br />with low stratigraphic dips commonly fall in the range from 23° to 27°." I <br />did not state in that memo, or during my discussion during the February 1 <br />inspection, that the U.S. Bureau of Mines report limited the angle of draw to <br />25-27 %. In addition, I indicated that my recall of the study's specifics, <br />which had been conducted approximately ten years earlier, could well be <br />flawed. My reference to the study was intended to provide a possible <br />reference for technical information regarding local subsidence characteristics. <br />(31 Mrs. Tatum requests a reference to information regarding my observations of <br />the Allen Mine angle of draw. In reference to my actual statement, <br />discussed above, I can offer a reference for Mrs. Tatum. I have attached a <br />copy of the Society of Mining Engineers of AIME Preprint No. 85-328, a <br />preprint of a paper I authored in 1985, entitled "Coal Mine Subsidence in <br />Colorado: Practical Application in a Regulatory Setting". <br />(4) Mrs. Tatum correctly observes that I stated in my memorandum of February <br />14th, that I was not familiar with Version 4.0 of the VPI Surface <br />Deformation Prediction System (SDPS) software. When last I used SDPS <br />software, over a year ago, our TIPS installation had Version 2 installed. The <br />OSMRE TIPS (Technical Information Processing System) computer software <br />package installed by OSMRE on the Division's TIPS computer now has been <br />upgraded to Version 4.0 of the SDPS. <br />15) Mrs. Tatum requests my thoughts regarding the BRI survey of the two <br />monuments adjacent to the railroad, which was provided to her office by <br />Holland and Hart, attorneys for BRI. These monuments were apparently <br />installed by BRI at their own discretion. These monuments were not required <br />as a portion of the approved mining permit application. Therefore, <br />submission of survey monitoring results was also not required. Randy Price <br />informed me that these results were provided to the Division, at our request, <br />after their existence was brought to our attention as a result of BRI's <br />interaction with the Tatum's. Had the Division been in possession of this <br />