Quality and inspection
Quality on a trenchless job is mostly a records problem. The work is buried within hours of being done, so what survives is whatever somebody wrote down at the time.
The inspection and test plan
One sheet per licence or segment, running the full phase sequence, with an authority matrix saying for each check whether a party reviews, surveils, verifies, witnesses or holds. A hold point means the work stops until it is signed. If nothing on your ITP is a hold point, it is not an ITP.
| Phase | What is checked |
|---|---|
| Document review | Drawings, procedures, permits and personnel qualifications, before anything moves |
| Grade and grub | Working width against the permitted footprint; ground disturbance clearance |
| Stringing and bending | Pipe identification, mill certificates, bend radius and ovality |
| Welding | Procedure, welder qualification, fit-up, and weld mapping to joint and heat number |
| Non-destructive examination | Method and acceptance to the code and the service; repair, re-shoot and acceptance |
| Coating | Surface preparation, application, daily adhesion testing, and holiday detection at lowering-in |
| Trenchless segment | Set-up, navigation calibration, pilot, ream passes, pull force and annular pressure logs |
| Gauging | Cleaning and gauging plate run, confirming the installed pipe is round and unobstructed |
| Pressure test | Strength and leak test durations and pressures to the code; cold-weather provisions |
| Reclamation | Restoration against the permit conditions and the pre-construction baseline |
The trenchless-specific records
These are the ones that are unique to a drilled installation, and the ones most often missing when somebody goes looking two years later:
- The navigation calibration record — daily, witnessed, with the instrument serial number. An uncalibrated locator makes every depth on the job an opinion.
- The bore log — rod by rod: pitch, depth, azimuth and annular pressure, continuous from entry to exit. This is the single most valuable document on the job.
- The pull-force log — recorded through the pullback against the computed allowable, not just a peak figure remembered afterwards.
- The fluid volume reconciliation — pumped against returned, per shift.
- The crossing report — for every foreign facility crossed: cover, separation, method, and the as-built handed to the facility owner.
- The electronic as-built — the installed path, georeferenced, uploaded while the crew is still there rather than reconstructed later.
When a crossing is disputed — a strike, a settlement, a depth question at a future excavation, a claim about what the ground actually was — the argument is decided entirely by the records made at the time. A complete bore log has settled disputes on its own. A missing calibration sheet has lost them.
What you get
- A project-specific inspection and test plan with the authority matrix and the hold points set.
- The record forms, aligned to the phases and to your document control.
- A turnover index: what the as-built package must contain to be accepted.
- Where we are also in the field, the hold-point witnessing itself.