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The S-wave velocities for soils at depths greater than 10 ft range from 500— 1,000 ft/s (approximate 1,000 — 2,000 ft/s P-wave velocity). The minor data misfit between arrays A and B against C are likely caused by scattering induced upon array C as the sensors were located immediately adjacent to buried concrete blocks. There is a clear contrast between modeled shear-wave velocity profiles for MASW arrays D and E (Tables 4 and 5), which were collected outside the interpreted drum-disposal area, and arrays A-C. The modeled shear-wave velocity profiles for arrays D and E indicate S-wave velocity of the upper 10 ft of approximately 480 ft/s (960 ft/s P-wave velocity). Below this zone, S-wave velocity increases with depth from about 750 ft/s (2,200 ft/s P-wave) to 900 ft/s (1,500— 1,800 ft/s P-wave velocity). Depth and velocity models for arrays D and E below 10 ft agree with MASW models A-C, as well as with the seismic refraction data. Comparison of MASW Arrays A-C to background Arrays D and E indicates that the disposal area is about 10 to 12 ft thick Rayleigh wave dispersions curves converge at a wavelength of 6m, which corresponds to an approximate depth of 3m (10 ft). This correlates well with the velocity and depth models from the seismic refraction survey. There is also a strong correlation with the interpreted depth section from the electrical resistivity survey. 6243 Versar 9 July 6, 2006