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Investigation into Continued Damage at the Solitario Ranch Page 10 1 1 space available to subside, for this model, would be on the order of 3 feet fora 6- foot thick coal seam. That thickness is reflected in the adjusted seam thickness in the parcel data. Calculated subsidence is the factor SU, and of course the point # is the prediction point. The other factors relate to strain that are rock mechanic functions. Prediction points 3 and 14 approximate the locations of measuring monuments 1N-1 and 1N-2 respectively. Because of the variable nature of rock strengths and the unknowns involved with the lack of survey coordinates on the house, these calculated figures would not be considered absolute, but instead clearly show that the Tatum house is within the influence of any subsidence of the mine. A rigid structure made of adobe could not sustain even very small movements, without damage. The program does not take into account the heave aspect that has been reported, especially in the pillar failure studies. The additional survey work provided by Basin and dated O1/OS/O1 may or may not be useful. The indication is that the work was done with a GPS instrument, and there needed to be closure to a second known station to check for accuracy. The commonly accepted order of accuracy for subsidence surveys is 2°" order and sometimes 3rd order, that is 0.35 times the square root of the distance surveyed in miles, or 0.5 times the same factor for third order. The comparison was made to the surveys done by Basin in 1988 and in 1995, but not to the Mincic survey and resurvey both done in 1993. An elevation mending process was explained above. Opinions and Conclusions It is my opinion that damage to the house and waterline have been caused by mine subsidence and that this subsidence has continued. Pillar failure is continuing in the 1 N entry especially in those pillars that were projected to have had partial failure previously. The initiation of the pillar failure may well have been related to the seismic shock that occurred on February 27,1991 which was in the right time frame. There may have been other seismic events that have not been recorded or noted since then. In any case, once the floor starts to fail there is no reason for it to stop, as additional weight is slowly applied to the pillars.