1. GEOPHYSICAL SERVICES Presented By: Hans van de Vrugt, CEG, RGp Patrick F. Lehrmann, PG, RGp SOUTHWEST GEOPHYSICS

2. Site Evaluation Direct Methods Boreholes/Probes Test Pits/Trenches Cores

3. Geophysical Techniques Indirect Methods Ground Penetrating Radar (GPR) Electromagnetics (EM) Magnetics Utility Locating Seismics Electrical Resistivity Gravity Very Low Frequency (VLF)

4. Advantages: Non-Destructive Cost Effective Provides Preliminary or Supplemental Information Geophysical Techniques Indirect Methods

5. Geotechnical Applications

6. Environmental Applications

7. Ground Penetrating Radar System Geophysical Methods SIR 3000 – 400 MHz SIR 3000 – 100 MHz

8. Ground Penetrating RADAR (GPR) Survey

9. Stratigraphy Survey GPR Data

10. 1500 MHz.5 m Structure Evaluation 900 MHz 1 m Structure Evaluation, Void Detection 400 MHz 4 m Engineering, Environmental, Void Detection 200 MHz 7 m Geotechnical, Engineering, Environmental 100 MHz 20 m Geotechnical, Environmental, Mining Common GPR Antennas

11. EM-31 Electromagnetic Conductivity: EM-61 and EM-31 Field Survey Equipment Geophysical Methods EM-61

12. Electromagnetic Conductivity Survey GROUNDSURFACE INDUCED CURRENT IN SUBSURFACE OBJECT GROUNDSURFACE PRIMARYFIELD SECONDARYFIELD

13. UST Search Electromagnetic (EM61) Survey Data

14. Magnetics - Magnetometer Equipment Magnetometer Gradiometer Geophysical Methods

15. Magnetics Survey

16. Magnetometer Survey Data 10,000 Gallon UST

17. Magnetometer Survey Data Abandoned Oil Well

18. Magnetometer Survey Data Lost Culvert

19. Geophysical Methods Seismic Refraction System

20. Seismic Refraction Survey

21. Seismic Refraction Survey Data

22. Depth To Bedrock Study Seismic Refraction Velocity Model

23. Geophysical Methods Sting/Swift Earth Resistivity System

24. Resistivity: Wenner Array Survey

25. Sting Dipole-Dipole Array

26. Landfill Investigation Earth Resistivity Profiling

27. Case Studies

28. Former Landfill, Proving Grounds

31. Undocumented Landfill Survey

32. Undocumented Landfill Survey Data Points

33. Undocumented Landfill Survey

35. Magnetic Survey Undocumented Landfill

36. Magnetic Data Map

37. Proposed Power Plant Site

38. Terrain Conductivity (EM31) Survey

39. Terrain Conductivity (EM31) Survey (EM Low)

40. Sting Results

41. ► Sir 3000 GPR W/ 400, 900 & 1600 MHz Antennas ► Geonics EM61 Time Domain EM Metal Detector ► Geonics EM31 Terrain Conductivity Meter ► Geometrics 858 Cesium Magnetometer ► Schonstedt GA 52 Magnetic Gradiometer ► RD4000, RD500 & Metrotech 9860 Utility Line Locators ► Fisher M-Scope TW-6 Pipe Locator ► Fisher M-Scope M-100 Rebar and Cable Locator ► Instantel Blastmate III Vibration Monitor ► Geometrics StrataView 24 Channel Seismograph ► AGI Super Sting R8 Resistivity Meter ► Trimble Pro XRS GPS Instrument List

42. Advantages/Limitations Advantages Advantages Non Destructive Non Destructive Quick Data Collection Quick Data Collection Cost Effective Cost EffectiveLimitations Depth of Penetration v. ResolutionDepth of Penetration v. Resolution Non Unique SolutionsNon Unique Solutions Undesirable Signals/NoiseUndesirable Signals/Noise

44. Illegal Drum Burial EM61 Data

45. Illegal Drum Burial GPR Data

46. Illegal Drum Burial Pay Dirt

47. Undocumented Landfill Survey

48. Site Map

49. Time-Distance Plot