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• The experimental site is not analogous to the site of the proposed quarry with regazd to geology, lithology, or topography. • Data analysis procedures are questionable, producing regression curves that do not fit measured data, and no statistical analysis of expected error, confidence levels, or significance of fit are provided. • No descriptions of field procedures, instrumentation, sensor calibration, or sensor spectral response are provided. • There is no discussion regarding the type of waves (compressional, shear, and Rayleigh) produced by various equipment and their relative amplitudes and decay rates. • The analysis of simple harmonic motion in the Revey report does not account for mechanisms that produce the highest amplitude ground motions such as wave guides and natural resonance. • There is no technical analysis using principles of rock mechanics or engineering, to assess the risk that vibrations from heavy equipment could destabilize fractured blocks in the Rollins sandstone cliff, and thereby threaten nearby outbuildings and homes. A more detailed explanation of these concerns is given in the following section. ANALYSIS OF CONCERNS 1) The eaperimental site is not analogous to the site of the proposed quarry with regard to geology, lithology, or topography. The Austin site used for field testing is located in either unconsolidated Quaternary deposits of sand and gravel, or in weathered Mancos shale which is fiiable clay-rich marine shale that forms the "badlands" in the azea. Photographs in Attachment I show the sensor and equipment in unconsolidated material. Yet the proposed quarry site is about 10 miles north of the site of the experiment and consists of lithified sandstone and shale of the Cretaceous Mesaverde formation. The "red shale" was formed by burning coal seams that baked the neazby sandstone and shale beds and oxidized iron. Layers of quartz cemented sandstone and baked shale aze interbeded, and the cemented sandstone forms an overburden in portions of the site. In order to justify the choice of experimental site, and its relevance to the proposed quarry location, the report should provide data that shows materials from the two sites have similaz intrinsic and in-situ elastic properties. This has not been provided, and in fact, the materials have very different characteristics. Ripping of lithified bedrock at the proposed quarry site will not produce the same seismic energy spectrum as pushing unconsolidated dirt with a dozer. Considering the very different nature of the sedimentary rock, topography, and