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<br />Memo to Susan McCannon <br />Tatum letters of May 24 & May 26, 1995 <br />page 2 <br />(a) As earlier stated, it is my opinion, as well as the OSM's Michael <br />Rosenthal, Kewal Kohli, PhD. And Jesse Craft, PhD., that no subsidence <br />has occurred above the workings of the 1st North entry area of the <br />Golden Eagle mine, which includes the workings closest to the Tatum's <br />residence. Further, it is the opinion of these four professionals that no <br />mining related ground subsidence has occurred at the location of the <br />Tatum's residence. <br />(b) The Golden Eagle mine is in the process of monitoring subsidence <br />monuments above their current longwall panels in order to perfect <br />observations and define the angle of draw for those longwall workings. <br />Basin Resources' earlier effort failed to precisely define the angle of draw <br />because of insufficient monument installation. Their data only allowed the <br />conclusion that the angle of draw was somewhere between 8° and 35°. <br />They have been required to install additional monuments and repeat their <br />monitoring. I anticipate that sufficient data should have been collected <br />by this fall to determine the angle of draw above their longwall workings. <br />However, this angle of draw may not be applicable to the situation <br />overlying the limited extraction (33% maximum) room and pillar workings <br />of an area such as the 1st North entries of the Golden Eagle mine. <br />(c) The SDPS subsidence prediction computer software has been applied to <br />the Tatum residence by other professionals involved in this exchange, <br />both by the OSM and by consultants working for the Tatums. The SDPS <br />will not project subsidence for workings with less than 75%extraction. <br />_ All of the modeling completed to date has required the inappropriate <br />assumption of 75%extraction and is therefore inappropriate for analysis <br />of the 1st North entries at the Golden Eagle mine. When this <br />inappropriate assumption is made, however, the SDPS software projects <br />an angle of draw in the upper twenty degrees from vertical. <br />(dl As I have stated in my memo of February 14, 1995, and repeated in <br />several subsequent memos; "Following my examination of the Tatum <br />