Use of Geophysics for Transportation Projects (2006)

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79 APPENDIX C Survey Results

80 3 95 0 2 0 0 N=58 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Federal Agency State/Provincial Agency County Agency Municipal Agency Private Organization Toll and Turnpike Authority No Response (Same as Figure 2) AGENCY RESPONSE TO THE USE OF GEOPHYSICS WHAT IS THE TYPE OF TRANSPORTATION AGENCY/ORGANIZATION? IF PRIVATE, WHAT TYPE? 000 0 0 100 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t A/E Engineering Firm Geophysical Consulting Company Professional or Trade Organization Other Private Organization State/Provincial Agency N=58 WHAT IS YOUR INVOLVEMENT WITH GEOPHYSICAL INVESTIGATIONS? (Same as Figure 3) 3 3 68 3 23 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Primary Major Minor Occasional No Response N=59 DO YOU HAVE A CASE STUDY TO SHARE? 35 58 7 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 PART 1—GENERAL #1 How Long Have You Been Involved with the Implementation of Geophysics for Geotechnical Applications? 9 17 19 16 14 17 9 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t < 1 Year 1 to 5 Years 6 to 10 Years 10 to 15 Years 16 to 20 Years 21 or More Years No Response N=58 #2 Who in Your Organization Implements the Use of Geophysics? 47 17 4 19 38 1 5 2 0 10 20 30 40 50 60 R es po nd en ts Geotechnical Engineers Civil Engineers Structural Engineers Pavement Engineers Geologists Hydrologists Other No Response N=133

81 #3 What Percent of Geophysical Investigations are Conducted by In-House, RFP, and/or IQ Contracts? 14 2 2 13 24 0 3 13 7 1 3 6 6 0 10 20 30 40 50 60 R es po nd en ts 100-76% 75-51% 50-26% 25-1% No Response In-House RFP IQ N=31 N=40 N=17 #4 Is Specific Training Offered to Staff on Geophysics? 5% 93% 2% 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #5 If #4 is Yes, Provide Information about the Training? 1 1 1 1 1 95 0 50 100 150 Pe rc en t Conferences, In-House, Consultants Engineers, Geophysicists, Contractors, Students, Professors, Geologists 2-3 per year Division Conference Funds Department #4 is No N=58 #6 Are You Aware of the FHWA (Web-based) Geophysical Manual? 69 29 2 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #7 Does Your Office or Agency Have a Hardcopy of the FHWA Geophysical Manual? 46 37 15 2 0 10 20 30 40 50 60 70 80 90 100 Yes No Don't Know No Response N=59 Pe rc e n t #8 Does Your Office or Agency Have the CD Searchable PDF-version of the FHWA Publication? 16 62 21 1 0 10 20 30 40 50 60 70 80 90 100 Pe rc e n t Yes No Don't Know No Response N=58

82 #9 Have You or Your Staff Used the Geophysical Manual? If So, What Format? 49 10 3 24 14 5 36 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No Don't Know No Response Web-based Hardcopy CD N=59 R es po nd en ts N=44 #10 Are You Aware of the FHWA Geophysical Manual Website that Provides Information on Geophysical Conferences? 50 47 3 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #11 Have You or Your Staff Used the FHWA Website? 29 43 5 21 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No Don’t Know No Response N=58 #12 What is the Typical Number of Geophysical Investigations Conducted by Your Agency Each Year? (Same as Figure 4) 9 56 12 5 10 3 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t <1 1 to 5 6 to 10 11 to 15 16 to 20 21 or > No Response N=58 5 #13 Has the Level of Effort Increased for Applying Geophysics on Transportation Projects over the Past Five Years, and, By What Percent? (Same as Figure 5) #14 Rate Your Personal Experience Using Geophysical Methods 20 44 19 8 5 0 4 0 10 20 30 40 50 60 70 80 90 100 Excellent Good Fair Poor Unacceptable Not Applicable No Response N=59 13 8 5 8 59 38 3 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Pe rc en t Yes No No Response <25% 25 to 50% 50 to 75% >75% N=58 R es po nd en ts N=34 #15 Rate Your Organizations’ Experience Using Geophysical Methods 8 46 34 7 2 0 3 0 10 20 30 40 50 60 70 80 90 100 Pe rc e n t Excellent Good Fair Poor Unacceptable Not Applicable No Response N=59

83 #16 Identify the Greatest Value Geophysics Lends to Your Transportation Projects (Same as Figure 6) 21% 19% 17% 15% 10% 10% 7% 1% Data Acquisition Speed Cost Benefit Better Subsurface Characterization 2D, 3D Subsurface Assessments Other Results Presentation No Response N=162 Other #17 What is the Greatest Deterrent to Using Geophysics on Transportation Project? (Same as Figure 7) 14 13 4 23 28 7 33 27 9 1 0 10 20 30 40 50 60 R es po nd en ts Cost Acquisition Issues Timeliness of Results More Questions Non-Uniqueness Results Format Lack of Understanding Lack of Confidence Other No Response N=159 #18 Do You Understand the Differences between Geophysical Testing for Geotechnical Applications and NDT for Evaluating Structures? 91 7 2 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #19 What is the Number of NDT Investigations Conducted Per Year? 9 17 5 2 3 38 19 7 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t 0 1 to 5 6 to10 11 to 20 >20 Don't Know Too Many to Count No Response N=58 #20 Identify the Applications Used for NDT in the Past Five Years (Same as Figure 8) 28 15 4 20 21 24 11 13 0 10 20 30 40 50 60 R es po nd en ts Pavement Condition Bridge Superstructure Baseline Measurements Concrete Condition Bridge Substructure Construction QA/QC Other No Response N=136 PART 2—METHODS AND APPLICATIONS #21a Seismic Methods Used within Past Five Years 34 10 10 23 5 3 2 9 0 10 20 30 40 50 60 R es po nd en ts Refraction Reflection SASW/MASW Crosshole/Downhole SeisOpt Remi Not Sure Other No Response N=96 #21b Electrical Methods Used within the Past Five Years 4 23 3 5 2 3 0 5 25 0 10 20 30 40 50 60 R es po nd en ts 1D Soundings 2D Profiling 3D Imaging Tomography Induced Polarization Self Potential Mise-a-la-mass Not Sure No Response N=70

84 #21c Electromagnetic Methods Used within the Past Five Years 13 7 3 7 1 0 4 37 0 10 20 30 40 50 60 R es po nd en ts TDEM TDEM Metal TDEM 1D Soundings FDEM VLF Seismoelectric Not Sure No Response N=72 #21d Ground Penetrating Radar Used within the Past Five Years 5 22 28 7 16 0 10 20 30 40 50 60 R es po nd en ts Did Not Specify Bedrock Mapping Soil Mapping Bedrock Fracture Mapping No Response N=78 #21e Magnetic Methods Used within the Past Five Years 1 3 1 7 48 0 10 20 30 40 50 60 R es po nd en ts N=60 #21f Gravity Methods Used within the Past Five Years 3 0 2 53 0 10 20 30 40 50 60 R es po nd en ts N=58 Did Not Specify Total Field Gradiometer Not Sure No Response Microgravity Gravity Not Sure No Response #21g Borehole Logging Used within the Past Five Years 1 9 2 7 7 5 10 1 5 34 0 10 20 30 40 50 60 R es po nd en ts Did Not Specify Electrical EM Induction Nuclear Optical Acoustic Seismic Hydrophysical Borehole Deviation No Response N=81 0 10 20 30 40 50 60 R es po nd en ts #21h Marine Methods Used within the Past Five Years 5 6 5 6 45 Fathometer Sonar GPR Sub-Bottom Profiling No Response N=67 #21i Airborne Methods Used within the Past Five Years 2 0 1 56 0 10 20 30 40 50 60 R es po nd en ts Magnetics Gravity EM No Response N=59 #21j Vibration Measurements Used within the Past Five Years 35 35 18 0 10 20 30 40 50 60 R es po nd en ts Blasting Construction No Response N=88

85 #21k Other Geophysical Methods Used within the Past Five Years 2 1 1 1 53 0 10 20 30 40 50 60 R es po nd en ts Falling Weight Deflectometer Marine Resistivity Laser Infrared Downhole Magnetic and Seismic Reflection ahead of TBM No Response N=58 #21L No Geophysical Methods Used within the Past Five Years 0 100 0 20 40 60 80 100 120 Pe rc en t None of Above No Response N=58 #22 Most Commonly Used Geophysical Methods (Same as Figure 9, See Table C1 for Details) 5% 9% 10% 22% 6% 22% 26% Seismic GPRVibration Monitoring Resistivity NDT Borehole Logging Others N=130 #23a Geophysics Applications Used within the Past Five Years 45 33 7 10 19 14 0 10 20 30 40 50 60 R es po nd en ts Bedrock Depth Bedrock Topography Bedrock Faulting Bedrock Fractures Bedrock Strength Bedrock Weak Zones N=128 #23b Geophysics Applications Used within the Past Five Years 15 7 8 4 1 0 10 20 30 40 50 60 R es po nd en ts Overburden Soil Lithology Bedrock Lithology Sand or Gravel Deposits Clay Estimating Clay Content N=35 #23c Geophysics Applications Used within the Past Five Years 0 9 0 0 10 20 30 40 50 60 R es po nd en ts Groundwater Salinity Groundwater Table Groundwater Flow N=9 #23d Geophysics Applications Used within the Past Five Years 8 1 7 3 4 0 10 20 30 40 50 60 R es po nd en ts Landslides Volume Assessment Slip Surface Identification Pre-slide Measurements Post-slide Measurements N=23 #23e Geophysics Applications Used within the Past Five Years 11 9 6 0 10 20 30 40 50 60 R es po nd en ts Engineering Properties Overburden Soils Rock Formations N=26

86 #23f Geophysics Applications Used within the Past Five Years #23g Geophysics Applications Used within the Past Five Years 34 19 12 13 11 23 17 0 10 20 30 40 50 60 R es po nd en ts Subsidence Features Natural Karst Dissolution Cavities Culvert/Sewer Failure Fill Degradation/Compaction Unknown Sinkholes Abandoned Mines N=129 27 21 11 14 1 3 0 10 20 30 40 50 60 R es po nd en ts Buried Man-Made Features Utilities Old Foundations Underground Storage Tanks Contamination Unexploded Ordnance N=77 #23h Geophysics Applications Used within the Past Five Years 8 7 2 0 10 20 30 40 50 60 R es po nd en ts Scour Around Foundations Other No Response N=17 #24 Most Common Applications of Geophysics (Same as Figure 10 and See Table C7 For Details) 1%10% 11% 22% 32% Others Bedrock Mapping NDT 24% Subsidence Investigations Mapping Soil Mapping Man-Made Features N=113 #25 What is the Overall Approach to the Selection of the Appropriate Geophysical Method (Same as Figure 11) 14 22 21 29 5 7 12 5 2 0 10 20 30 40 50 60 R es po nd en ts Contractor Specifications In-house Geophysicist Highway Engineer Experience Only Known Method ASTM / AASHTO No Formal Approach Preferences No Response N=117 #26 Who Approves the Selection of the Appropriate Geophysical Method? (Same as Figure 12) 3 18 3 2 6 24 13 18 1 0 10 20 30 40 50 60 R es po nd en ts Contractor Highway Engineer Program Manager Contracting / Procurement In-house Geophysicist Project Manager Division/Branch Manager Other No Response N=88 #27 Comments Regarding Other Experiences Related to Geophysical Methods and/or its Applications See Table C3 12 88 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Comment No Comment N=58 #28 Do You Make Budget Decisions for the Geophysical Program? 22 5 73 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 PART 3—BUDGETS AND COSTS

87 #29 Do You Make Budget Decisions for Specific Geophysical Projects? 66 2 32 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #30 Who Makes Budget Decisions Related to the Use of Geophysics (Same as Figure 14) 7 32 22 9 3 0 10 20 30 40 50 60 R es po nd en ts Agency Head Division/Branch Manager Team Leader/Project Manager Staff Highway Engineer No Response N=73 #31a Annual Budget Allocated to Geophysical Surveys (Same as Figure 13a) 7 2 14 10 67 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t > $100,000 < $100,000 to $50,000 <$50,000 None No Response N=58 #32 How Much Money is Spent Annually from Allocated Funds on Geophysics? 3 7 3 31 19 37 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t > $500,000 > $100,000 < $100,000 < $50,000 Different Every Year No Response N=58 #31b Annual Funding from 'Other' Funding Sources for Geophysics (Same as Figure 13b) 0 10 48 15 27 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t > $500,000 > $100,000 < $100,000 < $50,000 No Response N=58 #33 Prediction of Money Spent this Year on Geophysics (Same as Figure 15) 2 9 7 22 55 5 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t > $500,000 > $100,000 < $100,000 < $50,000 No Way to Estimate No Response N=58 #34 Percentage of Allocated Budget Spent by: 23 7 4 2 4 1 6 7 1 0 1 6 3 0 1 4 12 0 10 20 30 40 50 60 R es po nd en ts 100-76% 75-51% 50-26% 25-1% No Response Design Branch Construction Branch Emergency Response Other N=36 N=18 N=8 N=8 #35 Research Funds Allocated Annually to Geophysical Investigations 7 90 3 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58

88 #36 Do You Use Research Institutions or Contractors to Perform Research on Geophysical Investigations? 16 12 5 30 0 10 20 30 40 50 60 R es po nd en ts University/College Contractors Others No Response N=63 #37 Funds Allocated Annually for Emergency Repair for Geophysical Investigations 2 93 5 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #38 Do Costs Related to Geophysics Hinder or Help Your Highway Engineering Staff? (Same as Figure 18) 26 57 17 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Hinder Help No Response N=58 #40 What is the Rationale for Not Using Leading-Edge or State-of-the-Art Geophysical Methods (Same as Figure 17) 13 20 14 15 10 8 0 10 20 30 40 50 60 R es po nd en ts Cost Skepticism Lack of Management Buy In Other No Response 'No' Answer to #39 N=80 #39 Do You Use Only Standard, Proven, State-of-the- Practice Geophysical Methods? 69 21 5 5 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No Don't Use Geophysics No Response N=58 #41 Typical Cost Range of Investigations and the Number Per Year at that Cost Level (Same as Figure 19) 1.2 1 8 32 88.2 280 2 13 0 50 100 150 200 250 300 N um be r o f I nv es tig at io ns > $100,000 $75,000 to $100,000 $50,000 to $75,000 $25,000 to $50,000 $10,000 to $25,000 <$10,000 Other No Response #42 Comments Regarding Other Experiences on Geophysical Budgets and/or Costs See Table C4 14 86 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Comment No Comment N=58

89 #43 Who Writes the Scope of Work for RFPs and How are they Prepared? (See Table 3 for Details) 78 22 0 10 20 30 40 50 60 70 80 90 100 Pe rc en ta ge Response No Response N=59 #44 How Does Geophysics Get Incorporated into a Geotechnical Project, and How Do You Determine Which Projects Should Use Geophysics? (See Table C5 for Details) 86 14 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Response No Response N=58 PART 4—CONTRACTING #45 Use of In-House or Contract Geophysicists 7 26 23 2 0 10 20 30 40 50 60 R es po nd en ts In-House Contractor Both No Response N=58 #46 If You Self Perform Geophysical Investigations is the Geophysics Equipment Rented or Owned? 3 48 12 37 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Rent Own Both No Response N=58 #47 If You Self Perform Geophysical Investigations is the Geophysics Software Rented or Owned 3 5 40 52 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Rent Own Both No Response N=58 #48 What Type of RFP Solicitation is Used by Your Agency? (Same as Figure 21) 3%6% 7% 8% 11% 11% 12% 16% 26% Limited Solicitation Sole-Source Solicitation Open Solicitation Open Competition No Response Other Methods Web Solicitation Referrals All N=111 #49 Use of Larger Contract Vehicles (ID/IQ or On Call) (See Table C6 for Details) 26 64 10 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58

90 #51 Contract Award to Academic Institutions to Perform 'Run-of-the-mill' Geophysical Investigations because They Offered Best Value (Price) 14 83 3 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #52 Academic Contracts Awarded to Perform 'Run-of-the-Mill' Geophysical Investigations Based on Best Value (Price) 12 85 3 0 10 20 30 40 50 60 70 80 90 Pe rc en t Yes No No Response N=58 #53 Use of Academic Institutions to Perform Cutting- Edge Technology 22 73 5 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response #54 Use of Professional Contractors to Perform Cutting- Edge Technology 29 66 5 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #55 What Would Increase the Level of Comfort Using Geophysics (Same as Figure 25) 47 2 47 2 38 9 34 8 32 7 29 12 4 0 10 20 30 40 50 60 R es po nd en ts Yes No No Response N=271 Training Knowledge Experience Standards Easy Software Easy Equipment Database of Qualified Providers #56 Confidence Using Geophysics more Frequently on Geotechnical Projects (See Table C5 for Comments) 84 16 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Comment No Comment N=58 #50 Typical Type of Contract for Geophysical Transportation Projects (Same as Figure 22) 34% 17%14% 13% 10% 9% 3% Lump Sum Fixed Price Time and Materials Unit Price Low Bid No Response Cost Plus ID/IQ Other N=69

91 #57 Comments Regarding Other Experiences on Contracting Geophysical Service Providers 17 83 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Comment No Comment N=58 #58 Number of Successful Geophysical Projects within the Past Five Years (Same as Figure 23) 6 19 9 6 7 2 9 0 10 20 30 40 50 60 N um be r o f S u cc es sf ul P ro jec ts 0 Projects 1 to 5 Projects 6 to 10 Projects 11 to 20 Projects 21 to 100 Projects >100 Projects No Response N=58 #59 Number of Unsuccessful Geophysics Projects within the Past Five Years (Same as Figure 24) 10 32 2 0 1 1 12 0 10 20 30 40 50 60 N um be r o f U ns u cc es sf ul P ro jec ts 0 Projects 1 to 5 Projects 6 to 10 Projects 11 to 20 Projects 21 to 100 Projects > 100 Projects No Response N=58 PART 5—CASE HISTORIES/PROJECT EXAMPLES #60 Comments Regarding the Successes and Failures Experienced with Geophysics (See Table C7 for Details) 48 52 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No N=58 #61 Case Histories to Share for Successful and Unsuccessful Geophysical Projects on Highway Related Problems (See Table 4 for Details) 40 43 17 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #62 Sample Scopes of Work to Successful Geophysical Project (Not the Full Case History) 36 47 17 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Yes No No Response N=58 #63 Future Research Needs for Geophysics (See Table C8 for Details) 35 65 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Comments No Comments N=57 Part 5 Closing Comments (See Table C9 for Comments) 26 74 0 10 20 30 40 50 60 70 80 90 100 Pe rc en t Comments No Comments N=58

92 TABLE C1 THREE MOST COMMON GEOPHYSICAL METHODS Agency First Second Third AKDOT Downhole — — AZDOT Refraction Blast monitoring — CALTRANS Refraction Borehole logging GPR CFLHD Seismic EM Magnetic CODOT — — CODOT Vibration monitoring of pile driving operations ER CTDOT CSL GPR Vibration monitoring DCDOT Vibration monitoring — — FLDOT GPR Refraction — GADOT Vibration monitoring Seismic resistivity GPR IADOT Seismic Resistivity Vibration monitoring IDDOT Refraction Blasting vibration measurement Construction vibration measurements ILDOT None KSDOT Reflection Resistivity CSL KYDOT Resistivity Microgravity GPR MADOT Seismic GPR Vibration MDDOT GPR Resistivity Vibration MEDOT Refraction Resistivity — MIDOT Falling weight deflectometer GPR Vibration monitoring MIDOT CSL GPR — MNDOT Vibration monitoring GPR — MODOT Downhole seismic Resistivity GPR MSDOT Vibration monitoring GPR Refraction MTDOT Refraction — — NDDOT GPR — — NHDOT GPR Refraction Resistivity NJDOT GPR Tomography CSL NMDOT Refraction Crosshole FWD/GPR NYSDOT Refraction Vibration monitoring SeisOpt ReMi OHDOT Resistivity GPR Reflection OKDOT Refraction — — ORDOT Refraction Vibration measurement Magnetic ORDOT Vibration monitoring Magnetic and EM GPR PADOT Resistivity Crosshole Refraction PANYNJ Blasting vibrations Marine applications Crosshole surveys RIDOT GPR — — SDDOT Electric logs Vibration monitoring — TNDOT Resistivity GPR — TXDOT GPR Falling weight deflectometer Seismic UTDOT Vibration monitoring Refraction Crosshole logging VADOT Vibration monitoring Refraction Resistivity VTDOT CSL GPR Vibration measurement WFLHD Refraction Vibration measurement GPR/ER GPR GPR WIDOT Vibration measurement — — WSDOT Refraction Resistivity Optical televiewer WYDOT Seismic Vibration monitoring GPR Edmonton Vibration GPR Manitoba Terrain electrical conductivity (TEC) surveys GPR New Brunswick IP EM Seismic Ontario GPR Hammer seismic — Quebec Refraction MASW GPR Saskatchewan Borehole logging GPR Electromagnetic Refraction

93 Agency First Second Third AKDOT Depth to bedrock Mapping material sites Mapping roadway soils AZDOT Rippability Depth to bedrock Topography of bedrock CALTRANS Rippability Bedrock depth/topography Mapping man-made features CFLHD Mapping depth to bedrock Mapping clay/uncompressed soils Underground voids CODOT Depth to bedrock Subsurface anomalies — CODOT Embankment — — CTDOT Unknown foundation determinations–scour Bedrock depths Depths to unsuitable material (peat/highly organic soils) FLDOT Subsidence issues (real or imaginary sinkholes) Assessing (protecting agency against) damage due to construction vibrations Location of buried objects and utilities GADOT Blast/vibration monitoring Depth to rock/PWR Location of sinkholes, USTs, culverts, etc. IADOT Abandoned mines Unknown sinkholes Depth to bedrock IDDOT Depth to bedrock Mapping bedrock strength Determining engineering properties INDOT Crosshole Shear wave (CPT) TDR KSDOT Bridge foundations Surface investigations Underground mines or dissolution fronts KYDOT Depth to bedrock Mapping karst features Mapping abandoned coal mines MADOT Mapping buried features Mapping roadway subsidence lithology MDDOT Karst studies UST studies Vibration MEDOT Depth to bedrock mapping foundations Utilities and sinkhole mapping MIDOT Pavement design Vibration monitoring Void detection MIDOT Pavement cross section Utility location Locating steel in bridge decks/pavement MNDOT Vibration complaint analyses and compliance Pavement/base/subgrade investigations Modulus of base materials with FWD MODOT Determining engineering properties (shear wave velocity) of overburden (in-house SCPT and research MASW) Abandoned mines, caves, karst Rock profile, lithology MSDOT Subsurface mapping — — MTDOT Mapping depth to bedrock Mapping topography of bedrock Determining bedrock rippability NDDOT Thickness of pavements and bases Detection of buried RCP Test condition of bridge decks NHDOT Bedrock profile mapping Mapping soils Void detection NJDOT Abandoned mines Karst/sinkholes Unknown foundations NMDOT Bedrock depth/rippability NDT drilled shaft foundations/piers Pavement layers modulus NYSDOT Depth to bedrock for road cuts Mapping water table elevation in overburden aquifers Identifying possible voids or culverts OHDOT Abandoned underground mines — OKDOT Depth to rock Rippability Water table ORDOT Location of underground structures, tanks, drums Vibration monitoring Depth of overburden ORDOT Locating utilities Locating USTs — — PADOT Karst Mine voids Mapping bedrock surface PANYNJ Impact of microtunneling and directional drilling on surface pavements Minipile evaluations (continuity of grouted socket) Liquefaction assessments RIDOT Depth to bedrock/rippability Monitoring construction- induced vibrations Mapping UST locations SDDOT CSL drilled shafts — — — TNDOT Construction in karst areas — Mapping Old TABLE C2 THREE MOST COMMON GEOPHYSICAL APPLICATIONS

94 Agency First Second Third TXDOT Pavement layer stiffness Void, moisture, layer thickness, and damages under pavement Sinkholes, utility lines UTDOT Controlling construction and blasting vibrations Identifying bedrock and bedrock strengths Quality control for dilled shaft construction VADOT Vibration Karst Depth to bedrock VTDOT Foundation integrity Traffic and blast vibration monitoring Bedrock mapping WFLHD Mapping bedrock — — WIDOT Construction QA/QC Vibration of differential settlement monitoring — WSDOT Refraction 2D electrical resistivity Optical televiewer WYDOT Seismic GPR Blasting vibration Edmonton Mapping roadway subsidence Soil characterization — Manitoba Bedrock sounding Detecting voids under pavement, unsuccessful Detecting frozen soils or permafrost, inconclusive results Ontario Rockline Depth and consistency of aggregate deposits — Quebec Bedrock profile Determination of cavity formation in embankments due to culvert failure Vibration measures caused by traffic, blasting, or piling Saskatchewan Borehole logging Pavement thickness determination Locating buried aggregate deposits TABLE C2 (continued) THREE MOST COMMON GEOPHYSICAL APPLICATIONS Agency Comment CODOT 3D methods need more accuracy. Manitoba Should learn more about different geophysical methods and try to use to enhance the field investigation (i.e., drilling and sampling). MTDOT We are just implementing the use of geophysical methods on our projects; thus, our experience is limited. NHDOT It is not always possible to deliver “the desired” answer to the geotechnical engineer. They often want precise depth information and yes or no answers. NMDOT Remi used on karst geology with some success as verified by test pits. OHDOT Geophysical services are not readily available, so they are often not included in the project development effort owing to a lacking of time in schedule. VTDOT Very limited experience. TABLE C3 COMMENTS REGARDING EXPERIENCE RELATED WITH METHODS AND APPLICATIONS TABLE C4 COMMENTS REGARDING OTHER EXPERIENCES ON GEOPHYSICAL BUDGETS AND/OR COSTS Agency Comment CODOT Geophysics would normally be included in the cost of a geotechnical investigation. There is no allocated funding (that is to say, money set aside specifically for geophysical testing). Therefore, any costs associated with it are buried deep within the overall budget for a project. FLDOT Difficult to assess in Florida because such a high use of in-house resources. We do not tap into geophysics consultants enough. Looking into developing a statewide geophysics contract for districts to tap into and control the quality of the consultants. MDDOT Geophysical costs and budget are incidental to the general geotechnical explorations budget. We have one engineer who runs GPR for a small portion of his time. There are no allocated funds for it. MODOT In-house drilling/cpt can be mobilized quickly and the funding is already included in the Geotechnical Section annual budget (no direct cost to Project Managers/District budgets). Geophysical contracting typically takes 1–2 weeks to set up and this must wait until special funding can be arranged from outside of Geotechnical Section annual budget. Most Project Managers/Districts are hesitant or have difficulty finding funds for geophysical investigations. MTDOT Limited number of projects that have utilized geophysical methods; therefore, budget type information is limited at this time (the above-cited information is a very general estimate). NHDOT Mostly use in-house equipment and staff. Equipment purchases have been out of research funds based on specific research projects. NMDOT Based on in-house equivalent costs if consultant cost utilized.

95 Question 44: How does geophysics get incorporated into a geotechnical project; that is, how do you identify which projects should use geophysics? Agency Comment AKDOT Knowledgeable staff recommends it or consultant designers ask for it. AZDOT When traditional geotech sampling methods fail, we turn to geophysics. CALTRANS No formal process. Usually through project lead's experience and/or discussion with geophysics branch. CFLHD If the geotechnical engineer feels it is cost-effective to incorporate geophysical methods in the planning stages or if the use of geophysical methods reduces risk, such as in the case of UXO, or if there is no other way to obtain their data, such as in the case of vibration monitoring. CODOT Via the recommendation of the geotechnical engineer. CODOT Complexity. CTDOT It is incorporated into a project if it is determined that it is the best technique to get the required information. DCDOT When recommended by consultant. Edmonton Incorporated on the basis of experience or the requirement for specialized information that cannot be derived by more conventional means. FLDOT Through geotechnical engineer input. GADOT Determined by issues with access, speed of results, desire to limit damage to areas caused by drill rigs. HIDOT When it is deemed cost-beneficial to supplement borings with geophysics. IADOT Project-specific requirement and geologic review. IDDOT Site conditions access for drilling, supplemental to drilling. INDOT Base FHWA guidelines . KSDOT Regional geologist decision. KYDOT Geophysics is based on information obtained from drilling, available mapping, property owner information, and site location. MADOT Identification is based on magnitude of project, difficult subsurface conditions, and getting preliminary advice from consultants. Manitoba Recommended by the project engineers or geotechnical engineer. MDDOT Case by case. MEDOT Per recommendation of geotechnical engineer. MIDOT Need for pavement data, vibration monitoring, void detection, or consultant proposal for inclusion in subsurface investigation plan. MIDOT Requests from our regional offices. Ontario Normally when problem occurs. MNDOT By need. MODOT As needs are identified by personnel from the Geotechnical Section. We may consult with university faculty for their advice and suggestions as to the most appropriate methods and configurations/details of the geophysical investigation. MTDOT Generally identified on projects where supplemental information is required in addition to that obtained from conventional drilling and sampling, or on those projects/areas where conventional drilling methods cannot be utilized. New Brunswick When it will work, access, time, cost. NHDOT All geotechnical projects are considered when seismic refraction, GPR, or resistivity can help to determine the subsurface conditions. NJDOT Designer recommendations; prior knowledge of existing site condition. NMDOT Geologic application/suitability. NYSDOT It has been traditional to use seismic refraction to reduce the number of boreholes to identify depth to bedrock for cut areas. NYSDOT has been doing this since 1955. OHDOT Staff discussions between District Managing Engineer and a geotechnical engineer in our central office in the design resource section. OKDOT Materials Division, Geotechnical Branch specifies use. ORDOT Identify where lower-quality results can supplement data between borings, reducing the number of borings, or used to find suspected obstructions, cavities, etc. ORDOT Case-by-case defined need PADOT Geotechnical engineer or design consultant request. PANYNJ Experience on past projects. Quebec When drilling methods are very expensive or the bedrock profile is very variable. RIDOT Based on past experience, project location/scope, project budget; will a particular geophysical method provide data that are timely and cost-effective. Saskatchewan All projects use these methods. SCDOT Proposed by consultant or selected by geotechnical engineer. TNDOT Suggested by geotechnical consultant or specifically requested by Geotechnical Section. . TABLE C5 COMMENTS REGARDING INCORPORATING GEOPHYSICS INTO GEOTECHNICAL PROJECTS

96 Agency Value Length Number of Contractors CALTRANS >$100,000 3 years 3 contractors CFLHD varies — — GADOT $150,000 4 years 2 contractors KSDOT varies — — MADOT $200,000 2 years 1 contractor MDDOT $500,000 3 years 1 contractor MEDOT $4 million 4 years 1 contractor MODOT — 2 years 6 to 8 geotechnical consultants; 2 with established geophysics capabilities NCDOT $500,000 2 years 3 contractors NJDOT $300,000 2 years 1 contractor NMDOT $250,000 3 years 4 contractors PANYNJ $100,000 3 years 2 contractors SCDOT varies 3 years 5 to 8 contractors WFLHD $1 million 3 years 2 contractors WSDOT $300,000 3 years 2 contractors Question 60: Comments regarding the successes (Question 58) and the failures (Question 59) experienced by your agency. Agency Comment AKDOT Our successes have come in straightforward circumstances where we have used multiple methods. Our failures have come when we used geophysical methods in marginal situations and without a clear idea of what we were likely to get for results. CALTRANS Our failures have primarily occurred when a geophysicist was not consulted on the survey design or methodology, resulting in selection of an inappropriate method or the creation of a poorly defined scope of work. Secondary failure has occurred when we apply a method to a problem or areas where the applicability or site conditions are sub-optimal, but other means of obtaining the desired information are extremely limited. CFLHD The unsuccessful projects were actually research-oriented where new non-proven technologies were tried. DEDOT Unreliable data. GADOT Only unsuccessful application was the use of a method that did not apply to the site conditions. KSDOT KGS Seismic Group is top notice. KYDOT We have had problems with using ground penetrating radar owing to clayey soils. We have had success with both electrical resistivity and microgravity in identifying caves and sinkholes in karst regions. MADOT Sometimes depth of investigation is not reached or level of accuracy is not obtained. UTDOT No set policy, engineer, geologist decides . VADOT Depends on size and area geology. VTDOT The size and scope of the project is evaluated along with the need for subsurface information, the in-house resources available, and the budget. WFLHD Project Geotech. WIDOT QA/QC requirements; vibrations/settlement involving deep foundations. WYDOT Project geologist decides. Question 44: How does geophysics get incorporated into a geotechnical project; that is, how do you identify which projects should use geophysics? Agency Comment TXDOT Site condition survey. TABLE C5 (continued) COMMENTS REGARDING INCORPORATING GEOPHYSICS INTO GEOTECHNICAL PROJECTS TABLE C6 VALUE, LENGTH, AND CONTRACTORS FOR ID/IQ OR ÒON CALL” CONTRACTS TABLE C7 COMMENTS REGARDING SUCCESSES AND FAILURES OF GEOPHYSICAL INVESTIGATIONS

97 TABLE C7 (continued) COMMENTS REGARDING SUCCESSES AND FAILURES OF GEOPHYSICAL INVESTIGATIONS Question 60: Comments regarding the successes (Question 58) and the failures (Question 59) experienced by your agency. Agency Comment Manitoba We used Refraction Seismic Surveys for bedrock sounding and the results were satisfactory. We also used GPR for mapping roadway subsidence to determine voids/sinkholes within a rock embankment, and the results were inconclusive or unsuccessful. MEDOT Seismic refraction has been most successful when there is enough boring data for calibration. It is great for go/no go decisions on entirely new highway alignments. MIDOT Used seismic to determine depth to bedrock on bridge project. Consultant got it wrong and it proved to be waste of money. MIDOT In some cases we were trying to utilize GPR in new ways and inadequate education/experience with the equipment probably led to the objectives not being realized. MNDOT We generally have success with the vibration monitoring equipment . MTDOT We have just begun the implementation of geophysics on projects ; previous use of geophysics was very limited. NCDOT Hard to quantify; hard to generalize. NHDOT Geotechnical engineers expecting too much from geophysics (GPR, seismic refraction, resistivity) on every project they consider its use on (i.e., if it can't give them the exact information they want, it is no good). NMDOT GPR in finding. NYSDOT We have been using seismic refraction in a great variety of settings, for numerous uses, fo r many years. We generally give answers to depth to bedrock within a 10% error range. Because we are in a glaciated region, where the weathered bedrock has been eroded, there is a good velocity contrast between the rock and the overburden glacial soils. It almost always works, except for one situation a few years back when we had a velocity inversion caused by gaseous silts in lake waters. We conduct vibration monitoring surveys routinely, for construction, blasting, and traffic vibrations. OHDOT GPR is very limited regionally owing to combination of typical site characteristics of clay soils and high (near surface) groundwater table. Ontario Failure to accurately plot rock line. PANYNJ Detection of buried drums; induced current conductivity. Quebec We have good results with our seismograph, which represents at least 75% of our geophysical survey. We have less success with seismic refraction survey done by private office. WISDOT WISDOT does not contract out very often for geophysical services because of cost. I am sometimes required to use one of the geophysical methods that are not appropriate for a particular project, simply because we own the equipment. I hear from project managers/engineers “let's do it anyway.” These are cases where an unsuccessful outcome is virtually guaranteed. TNDOT Methods have been proposed that do not really deliver what was promised or were generally unsuitable for the desired outcomes. TXDOT We are very happy with NDT. UTDOT Struggled to identify the shear plane in a landslide. VADOT Problems with seismic refraction in Piedmont saprolites and variably consolidated coastal plain sediments. Usually insufficient available space to lay out spreads for adequate depth penetration by our available practice. WSDOT Highly skilled geophysical consultants that try different method on the site to obtain the best result.

98 Agency Comment CALTRANS For transportation engineering, ways to quantitatively determine in situ soil and rock properties are a worthy avenue for future geophysical R&D. The biggest area for R&D, in my opinion, lies in NDT for roadway and structure maintenance, unknown foundation assessment, and construction QA/QC. CFLHD 3D crosshole tomography and ReMi. FLDOT Any assistance to provide guidelines to the geotechnical engineer to use geophysical testing to plan out the subsequent boring/sounding program to identify nonselect soils, isolated rock formation, map out top of rock, etc., would be enormously helpful. Case studies, lessons learned, cost savings, contracting mechanisms, etc., would help the engineer implement this testing on a routine basis. The need to relate geophysical test results to engineering properties is needed. New geophysical techniques are needed to be developed in conjunction with existing/boring sounding test methods so they can be performed at the same time. FLDOT has an existing pool fund study request to look into these two items. GADOT Additional use and experience along with training (through NHI or others) would be needed. IDDOT Pursue out-of-the-box methodologies. ILDOT Continue developing existing techniques. INDOT Soil characterization (stiffness, density, and moisture) . KSDOT Speed and ease of data filtering to allow us to present the information to all levels of transportation people. KYDOT Develop a NHI class for the states to reinforce the use of the technology. MIDOT Need to develop technology for continuous monitoring for compaction equipment to improve quality control of compacted soils. MTDOT Continue developing reliability and confidence in the output from geophysical surveys. NHDOT “Out of the box” technologies that are easy to use by in-house staff. Training to address geotechnical engineers expecting too much from geophysics (GPR, seismic refraction, resistivity) on every project they consider its use on (i.e. , if it can’t give them the exact information they want, it is no good). NJDOT One of the major obstacles to the utilization of geophysical methods is the susceptibility to interpretation and potential inaccuracy of obtained results. Any developments that will serve to reduce this situation will result in an increased level of confidence in both existing and new geophysical technologies. NYSDOT I’m a geologist, not an engineer, but I think the SeisOpt ReMi software holds great promise. Our experiences with it so far have been very favorable, not only for delineating shear wave velocities, but also for detecting voids above failing culverts. It is extremely easy to use in the field; using ambient noise for the energy source. OHDOT One area would be to complete the proposed pooled funding effort to determine how falling weight deflectometer data can actually be used as a form of seismic (?) data to determine areas underlain by subsurface voids. If this information could be developed, there would be a major victory in terms of cost-effective R&D. This cost-effective win would be because every DOT has FWDs, but right now most of them do not know that they can be used for more than pavement testing. Some of the states currently interested in this possible use of FWDs to detect subsurface voids include Ohio, Arizona, Kansas, Michigan, and Missouri. PADOT Ease of use, good interpretation tools, reduction in equipment and software costs, need to mainstream. PANYNJ Developing geophysical applications to assist with tunnel design; potential alignment may be investigated using directional drilling (install two pipes horizontally and perform crosshole measurements between pipes to interpret soil and rock strata). TNDOT Training, training, training, and training TXDOT GPR. Manitoba Geophysics is a specialized field. If geophysicists could provide marketing information/education, general geophysics applications for transportation, structure, and geotechnical engineers through universities, various conferences, trade shows, etc., this will be one of the keys to promote this technology. Quebec We are developing the Sherbrooke University and investigation method using MASW to find cavity formation in embankments owing to failure culvert. TABLE C8 FUTURE RESEARCH NEEDS IDENTIFIED BY RESPONDENT AGENCIES

99 Agency Comment ILDOT This survey is the longest survey I’ve seen! Too many questions to keep focused! INDOT We like training, knowledge, and information sharing. KYDOT We are in the process of completing a research project of different geophysical techniques. This research study involves evaluating and implementing several geophysical methods and different contractors for further use in the state of Kentucky. If you would like a copy of this report, contact us when it is completed. Until recently, Kentucky has lacked a budget. Also, owing to tight time constraints during the design phase geophysical techniques have not been incorporated. MADOT We responded to a similar survey about 2 to 3 years ago to FHWA. MIDOT Answers to this survey pertain to the use of GPR by our Pavement Structures Group only. Our Geotechnical Services Unit passed it on to us to fill out with regards to GPR only. It is important to note that the greater portion (>80%) of our work with GPR has been in the pavement structure (i.e., above the original subgrade) or in bridges. So, the type of work this survey is trying to document has been very minor in the 4 years we have owned the equipment. MNDOT There are two areas of interest in MNDOT concerning the use of geophysics. There is the pavement side that routinely uses GPR and FWD. The other area is the structures side that has used geophysics on occasion to attempt to enhance and fill in the blanks of a standard site investigation involving SPT and CPT. Potential failure emphasis will include preliminary investigation with geophysics to help determine a course for a more detailed site investigation and testing program. MODOT Question 6 references the geophysics manual. The only problem is that it is so voluminous as to discourage its use somewhat. There is need for an expert system to aid engineering professionals in the selection of the appropriate geophysical methods. Question 13 asks about increase/decrease in use of geophysics. Our increase is generally related to in-house SCPT utilization for shear wave determination using downhole seismic techniques and not other in- house or contracted geophysical investigation. MSDOT I’m all for a program designed to expand the knowledge of geophysical methods among state DOTs. We would utilize the varying technologies if we had the training needed to understand what is available and how it can be used to enhance our designs. MTDOT Our previous experience with geophysics is limited and we have just implemented its use within the past year. Thus, our experience and ability to provide case histories and budget type information is limited at this time. I anticipate increased use of geophysical methods in the future. OHDOT Please send me a copy of this synthesis whenever it is completed. Thanks! PANYNJ Regarding specific projects referenced in responses, it should be noted that all data were lost on 9/11. RIDOT We are presently coordinating an effort to develop a database of prior borehole information throughout the state. An interest exists in reducing a number of point borings and geophysical methods, in accordance with prior data, which may be quite beneficial in this pursuit. Saskatchewan Saskatchewan Highways and Transportation has been utilizing geophysical methods in geotechnical practice since 1966. It is part of the everyday toolbox that is used in this organization and the time and money saved over the past 40 years would be very large. New technologies such as EM surveys and GPR surveys have made sub-surface aggregate location studies and Pavement Engineering more efficient as well. SDDOT The state of South Dakota does not do much geophysics for projects. The amount that is done is through CSL of drilled shafts with potential irregularities. There has been some discussion on GPR, but very little progress. WIDOT Good job in putting the questionnaire together—you have covered all of the bases. I believe this will benefit WISDOT and many other state DOTs. Thank you for your efforts. Yellowknife Our agency used GPR with limited success; on two occasions about 12 to 15 years ago to detect near surface cavities under roadways, which were caused by permafrost degradation in one case and by dissolution of gypsum bedrock in the other case. TABLE C9 COMMENTS REGARDING ITEMS NOT COVERED IN THE SURVEY