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f DMG had conducted additional investigations of the Tatum home. In its letter, the DMG stated that it had concluded that the Tatum residence is not within an area where mine subsidence related to the 1st North Main of the Golden Eagle mine is occurring or has occurred. Therefore, the Tatum residence is not subject to mine subsidence impacts. DMG indicated that it was attaching to the letter a copy of a letter to the.Tatums informing them of the DMG's findings. See AR III-3. Attached to the letter to the Tatums was the Pendleton report issued on February 8, 1995 (see item 9, above). DMG also attached to the letter to OSM the February 16, 1995, "trip report" of OSM employee Mike Rosenthal (see item 10, above). 13. By letter dated February 28, 1995, OSM Regional Director Charles Sandberg explained to Ann Tatum how OSM had used a computer model to determine that subsidence was not occurring under the Tatum home. Mr. Sandberg explained that [als our original calculations indicate, using the actual extraction ratio, extraction thickness, and percent hardrock from the geological maps, subsidence would not occur. In order to obtain an angle of draw of 34.52 degrees, we had to double the extraction thickness (to 15 feet), half the percent of hardrock (to 15~) and assume 100 extraction (versus 31~). The calculations are shown on the attached computer printout. As you can see even with this theoretical situation, the subsidence would not reach your house (644 feet from the center of the main panel). At approximately 60 feet from your house, the subsidence would be less than one-eighth of an inch. We noted that under this scenario, that the railroad would have dropped 9.11 feet as it is located at the center of the subsidence curve. We found no evidence in the field indicating that the railroad tracks had subsided. 7