We provide geophysical services including underground utility locating, concrete scanning, underground storage tank locating, underground void locating, etc.

The following is a list of applications of our geophysical services:

Phase II Environmental Site Assessment (1) - Regular Services

• UST locating -- Metal Detecting and GPR
• Underground utility designating/drilling location clearance
• Concrete scanning/coring location Clearance

Phase II Environmental Site Assessment (2) - Advanced Services

• Phase I might not reveal all potential environmental problems
• EMI is efficient in large areas searching for potential unknown environmental contamination sources such as septic systems, oil-water separators, drums, disposal pits, fire pits, illegal burials, dumping, etc.
• Both metallic and non-metallic sources could be detected
• GPR surveys can follow in potential interested areas identified from EMI surveys

Utility markout/Underground Utility Designating

• Precision Locating, GPR and EMI Mapping

Concrete Scanning/Coring Location Clearance

• Locating conduits, rebar, post-tension cables and other targets embedded in concrete structures
• High resolution GPR scanning -- safe and cost effective compared to X-ray scanning
• Additional Precision Locating techniques can also be applied when needed

Underground Storage Tank (UST) Locating

• Delineating scopes of steel and fiberglass USTs and locating associated piping
• Metal detecting and GPR to search for potential unknown USTs
• Delineating past UST excavation areas

Vertical/Near-vertical Bedrock Fracture Zones Detection with Surface Geophysics

• Fracture zones could be missed with only sporadic drilling
• ERI -- high resolution 2D and 3D imaging, restricted in areas without much underground utility or reinforced concrete, etc.
• MASW -- 2D and 3D imaging, no similar restriction as in ERI, but the ground surface needs to be relatively flat
• Seismic refraction, EMI, VLF, etc. -- imaging with less dimensions and/or resolutions but could be more efficient in some situations

Groundwater Contamination/Saltwater Intrusion Investigations with Surface Geophysics

• Determining lateral and vertical variations in soil, rock and groundwater characteristics
• Mapping the extent of groundwater contaminants presented within aquifers
• Compared to drilling, geophysics provides rather continuous information in both horizontal and vertical dimensions
• 3D high resolution ERI is particularly useful
• 4D (time-lapse) ERI can be set up to monitor contaminant migration or remediation progress over time

Bedrock Fracture Delineation with Borehole Geophysics

• Geophysical Borehole Logging
• Fracture depth, dip and azimuth -- high resolution optical and acoustic images
• Identifying active inflow and outflow fractures by measuring vertical flow rate as low as 0.03 gpm
• Other tools: Gamma, SP, SPR, Caliper, Normal Resistivity, etc.

Groundwater Quality Monitoring with Geophysical Logging

• Integration of borehole geophysics logging with water quality sampling provides a more complete picture, whether the objective is to develop a water supply well or remediate a contaminated aquifer
• Typical downhole tools: Fluid Resistivity and Gamma

Determination of Well Construction and Conditions with Geophysical Logging

• Wells for water supply, monitoring, or remediation
• The location and condition of casing and screen can be rapidly evaluated with geophysical logging.
• Typical downhole tools: Optical Televiewer and Acoustic Televiewer
• A Downhole Video Camera can also be used for a supplemental 3D perspective

Depth to Bedrock Profiling

• Geophysical surveys can be conducted in areas not accessible by drilling equipment
• Geophysical surveys provide continuous bedrock-overburden interface instead of sporadic points provided by drilling
• Typical geophysical methods: ERI, Seismic Refraction and MASW

Cavity/Sinkhole/Underground Void/Mine Shaft/Tunnel Locating

• Ground penetrating radar -- for shallow targets; highest resolution
• Electromagnetic induction -- fast reconnaissance for large and shallow targets
• ERI -- high resolution 2D and 3D imaging, restricted in areas without much underground utility or reinforced concrete, etc.
• MASW -- 2D and 3D imaging on relative flat ground surfaces without similar restrictions on ERI
• Other methods: Microgravity, Magnetics, Seismic Refraction Tomography, etc

Landfill Delineation

• Lateral extents delineation – EMI: more efficient than GPR, and less prone to noises than Magnetics
• Vertical extents delineation – ERI; seismic methods are generally not recommended due to severe attenuation of seismic waves in loose materials
• Landfill leachate -- EMI, ERI and other geophysical methods could help to find leak locations and leachate travelling paths

Locating Hidden/Unmarked Burials in Cemetery/Graveyard

• Geophysical surveys are non-intrusive
• Typical methods: GPR, EMI and Magnetics

Soil Resistivity/Ground Resistance Testing for Electrical Grounding System

• Wenner array 4-point method -- ASTM G57-06 and IEEE Standard 81
• Fall of potential 3-pin method -- IEEE Standard 81

Marine Geophysics

• Underwater Utility Locating
• Sub-bottom Profiling
• Marine ERI
• Marine Metal Detecting

Archaeological Geophysics

• Non-destructive
• Cost effective by providing a base map (data mapping) for potential archaeological/historical sites
• Underground and underwater targets
• Helping to narrow down search areas and determine excavation priorities
• Typical methods: Magnetics, EMI, GPR, ERI and Microgravity.

Forensic Geophysics

• Detecting underground weapons and human burials
• Non-destructive
• Quickly searching in large areas
• Typical methods: GPR, Metal Detecting and EMI