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consists of collecting multi-channel seismic data in the field and applying a wavefield transform to obtain the dispersion curve and data modeling. In the MASW method, ground motions are recorded by 24, or more, geophones aligned in a linear array and connected to a seismograph. A wavefield transform, such as the f-k or r-p transform, is applied to the time history data to isolate the surface wave dispersion curve. The dispersion curve is then modeled to obtain the variation of shear-wave velocity with depth. The theoretical model used to interpret the dispersion assumes horizontally layered, laterally invariant, homogeneous-isotropic material. Although these conditions are seldom strictly met at a site, the results of MASW testing provide a good "global" estimate of the material properties along the array. The results may be more representative of the site than a borehole "point" estimate. 3.2 Seismic Field Procedures Seismic refraction data were collected along 3 profiles (SL-1 to SL-3) within the bounds of the survey area. MASW data were collected along three arrays (Arrays A, B, and C) within the suspected burial area and two arrays (D and E) outside the interpreted limits of the drum disposal area. Endpoints of the seismic profiles and MASW arrays were mapped using the Sokkia Axis-3 submeter GPS and are shown on Figure 1. Seismic refraction equipment used during this investigation consisted of a Geometries Geode signal enhancement seismograph, 8-10 Hz vertical geophones, seismic cable with 15-foot takeouts, a 20-lbs sledge hammer and aluminum plate. Each seismic line (SL-1 and SL-2) consisted of a single spread of 24 geophones spaced 3.28 ft apart for a total line length of 75.44 ft. All geophone and shot point locations were measured using a 300 ft tape measure. Relative elevations of each geophone location were calculated from elevation data collected during the electrical resistivity imaging survey. A typical seismic refraction field layout is shown in Appendix C. Multiple shot point locations were occupied on each spread: end shots at geophones 1 and 24, off-end shots placed far-enough off the ends of the line to image only the deeper refractor, and multiple interior shots spaced evenly throughout the spread. The sledgehammer was used as the energy source for all shot locations. The fmal seismic record at each shot point was the result of stacking 5-10 multiple shots to increase the signal to noise ratio. All seismic records were stored on the hard disk of a laptop computer. Data files were named with the sequential line, spread, and shot number and a ".dat" extension (i.e. data file 115.dat is the seismic record from line 1, spread 1, shot 5). MASW data was collected at five locations (Arrays A to E). A typical MASW field layout is shown in Appendix C. MASW equipment used during this investigation consisted of a Geometries Geode signal enhancement seismograph, 4.5 Hz vertical geophones, seismic cable with 15-foot takeouts, a 3 lbs hammer, a 20 lbs sledge hammer and aluminum plate. MASW data was acquired along linear arrays with a 0.5 - lm geophone spacing. The 3 lbs hammer and 20 lbs sledge hammer were used as energy sources for each array. Shot points were located 0, 1, 6243 Versar 6 July 6, 2006