Pre-construction subsurface intelligence for project teams in Virginia and Washington, DC.
What it reveals
Findings are confidence-classified, not presented as exact locations or guaranteed depth. Credibility comes from honesty about what the investigation confirms.
Related: Private utility locating
Site conditions
GPR is an interpreted geophysical method. Ground conditions, target material and orientation, congestion, surface access, and the survey pattern all influence what the evidence can support.
Process
GPR work runs inside the same methodical investigation sequence as the rest of the service line, with deliverables structured for contractor and engineering workflows.
ASCE 38-aligned methodology
01Scope
Understand the site, intended work, and decisions the project team needs to make.
02Investigate
Apply the field methods appropriate to the site and the infrastructure in question.
03Classify
State confidence in findings instead of presenting uncertainty as exactness.
04Document
Deliver a defensible record in formats that fit contractor and engineering workflows.
Field position and signal response are interpreted in site context, then documented with confidence and limitations stated.
Interpretation is part of the finding.
Site conditions affect what GPR can confirm. Findings are confidence-classified rather than presented as exact locations or guaranteed depth.
Deliverables
Deliverables are structured for contractor and engineering firm workflows, drawing on the documentation range from KMZ files to pre-construction intelligence reports.
No. Findings are confidence-classified, and site conditions affect what can be confirmed.
Ground conditions, congestion, material, and access can change what a GPR investigation can confirm on a given site.
It supports the investigation when the target or condition calls for it, alongside utility designation and mapping.
No. GPR is one investigation method within the service line. Private utility designation covers the designation and documentation of privately owned lines.
Method fit
GPR may stand alone for a defined subsurface question or work alongside electromagnetic designation and mapping. The scope should follow the evidence needed, not a preferred piece of equipment.
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| Project condition | Investigation | Usable record | Decision supported |
|---|---|---|---|
| Conductive utility with an accessible connection | Electromagnetic designation may provide a direct locating response. | Designated alignment and documented finding. | Plan around a traceable private utility. |
| Non-conductive or untraceable target | GPR can investigate for a plausible subsurface reflection when conditions permit. | Interpreted anomaly with stated confidence. | Determine whether further verification is warranted. |
| Congested or uncertain site | Use complementary methods and a deliberate survey pattern. | Combined field evidence, mapping, and limitations. | Coordinate work without treating uncertainty as exactness. |
Tell SafeLine where the project is, what work is planned, and what the project team needs to know before excavation or construction begins.
Virginia and Washington, DC