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Memo to Dan Mathews Red Canyon Mine Structure Examination page 2 well above the frost line on the south side of the structure. Hairline cracking in the basement floor suggest a slight opening resulting from a slightly convex heaving. Basement level bearing walls are placed on the slab-on-grade without expansion voids. No caisson elements were included in the foundational system. The upper story of the structure consists of a cellular structure of walls defining rooms in the eastern 2/3's of the structure. The western 1/3 is a large open living area. The interior drywall cracking is concentrated in areas near the center east -west ridge line of the roof. Cracking also exists along interior walls where they meet the ceiling. Cracking appears more concentrated adjacent to the walls which separate the boxed east portion from the open west living space. The bearing wall of the basement level extends generally beneath and supports the western boxed portion of the upper story. Cracking exists at the lower corners of asemi-circular clear story window high on the northern wall eve of the large open living azea. This clear story window sits above a multiple header beam which appears adequately sized for window wall which it spans. Without precise monitoring, it appears that beam deflection of the wide roof span in this open area may be deflecting the cleaz story wall outward above the header, causing the drywall to crack immediately above the header. The clear story wall does not appear noticeably deflected, suggesting that the cracking may be resulting from cyclic flexure in response to wind uplift and snow load. Recommendations: (1) The coincidence of the foundation cracks to the wall deflections and damp backfill areas suggests that the water service may be leaking into the foundation backfill outside the half wall. The service water flow should be monitored. If necessary a test hole could be excavated in the immediate area to determine whether the backfill is abnormally damp. (2) High-clay content soils, such as those weathered from the siltstone and claystones common in the Williams Fork formation, can swell upon absorbing water and shrink upon drying. The result of these alternative wetting and drying cycle movements can be damaging to an overlying structure. Shrinklswell potential of soils and bedrock can be easily and relatively inexpensively determined in the soil laboratory. Minor cyclic shrink- swell of the soil beneath the slab-on-grade could cause the minor heaving of the basement floor. At this point the damage appears minimal, so I suspect the swell characteristics of the foundational soils is low. Remedial methodologies exist with which to stabilize moisture and preclude significant deflection.