Excavation permit process flowchart (ground disturbance)

What the excavation permit process flowchart (ground disturbance) process is

An excavation permit, or ground disturbance permit, is the authorisation to break ground in a defined place, to a defined depth, by a defined method. It exists because two hazards sit under every dig and neither is visible from the surface: the services somebody buried there, and the ground itself, which is stable until the moment it is not. The trigger is a job that will disturb ground, whether that is a trench for a new duct, a foundation, a pole, a soakaway or a core through a slab. The chart below follows one permit end to end: the request with its location and depth, the records collected and the dig notice lodged, the locator's marks checked against those records, hand or vacuum digging inside the tolerance zone, the competent person's soil classification and support decision, edge protection and access, the issuer's site inspection and the time-limited permit, the inspection before anyone enters, the exception paths for water and for a service nobody had drawn, and the backfill, reinstatement and closure that put the record back where the next crew will find it.

This is the excavation-specific permit, not the general permit-to-work system it usually sits inside. A site's permit-to-work process covers permit types, authorisation levels, isolation certificates and shift handover across every kind of hazardous work; this chart takes those as given and draws only what is particular to breaking ground. It is not a confined space entry, even though a deep trench can become one, and the atmospheric testing, attendant and rescue arrangements that go with that belong to the confined space process. Nor is it lockout of the plant being worked on, or the traffic management plan for the road the trench crosses; both run alongside and are named on the permit rather than drawn here. The boundary matters because this permit's job is narrow and specific, and a chart that also carries the whole permit system stops being usable by the crew standing at the edge. Treat it as a starting point to be adapted under your own procedures, the regulations in your jurisdiction and your own competent person's review.

Five decisions carry the process. 'Marks agree with the records?' is the first, and it sits in the competent person's lane rather than the locator's because the person who swept the ground should not be the only one judging whether the result is believable. 'Digging inside the tolerance zone?' decides whether a machine may be used at all, and it is the decision most often taken by whoever is holding the bucket controls instead of on paper. 'Slope and bench, or shore the sides?' is the support decision, and it belongs to the competent person because a classification and a support system are one judgement rather than two. Then the process turns into a cycle: 'Excavation and supports sound before entry?' runs before every shift and again after rain or a load placed near the edge, and 'Excavation work complete?' either sends the trench round that loop again or releases it to backfill. The two exception paths, water or ground movement and a service nobody had drawn, both stop the work before anyone discusses it.

What this flowchart covers

In this template

• Five swimlanes (Requester / contractor, Utility / services locator, Competent person, Permit issuer and Site supervisor) across six phases: request, locate services, design the support, issue the permit, dig and inspect, and backfill and close
• A locating phase that treats records and marks as two different things: utility records collected and a dig notice lodged, the ground swept and marked, and a "Marks agree with the records?" decision that sends a conflict back for a re-survey rather than into the trench
• A "Digging inside the tolerance zone?" decision that routes the work to hand or vacuum digging before a machine goes near a marked service, and a separate path later in the dig for a service struck or never drawn, which stops the work and goes back to the locator
• The competent person's classification and support decision drawn as one sequence: soil classified by visual and manual test, then "Slope and bench, or shore the sides?", then shoring, a shield or an engineered design where the tabulated case does not fit
• A permit gate with something behind it: "Marks, support and edge protection in place?", a gaps branch that goes back to edge protection, access and spoil placement, and a time-limited permit tied to the marked footprint and the agreed depth
• The dig drawn as a daily cycle rather than one step: "Excavation and supports sound before entry?" before every shift, "Water, movement or an unmarked service?" during it, and "Excavation work complete?" looping back or releasing the trench to as-built records, backfill and a handback decision

When to use this template

• You are writing or rewriting a ground disturbance procedure and need one picture of who locates, who classifies, who issues and who inspects
• Machines are reaching marked services before anyone has hand-dug, and you need the tolerance zone rule drawn where the crew will actually see it
• You are a principal contractor setting the permit rules subcontractors will work to, and want the handoffs agreed before the first trench opens
• Daily inspections are being signed in the site office rather than at the edge, and you want the pre-entry gate drawn as the decision it is
• A client, insurer or regulator has asked how excavations on your site are authorised, supported, inspected and closed

How it works

1. Rename the lanes to your roles

   Replace Requester / contractor, Utility / services locator, Competent person, Permit issuer and Site supervisor with the roles you actually have. On a small job the supervisor is often the competent person and sometimes the issuer as well; merge those lanes rather than drawing a handoff nobody makes, but say in writing who holds the competent person's decisions once they are merged.

2. Write your permit trigger onto the first decision

   State what counts as ground disturbance on your site: a depth, any penetration of a surface, or a named list of activities including coring, stake driving, pile boring and post holes. Say who may decide that a job falls below the threshold, and record that decision, because the jobs that hit services are rarely the ones that looked like excavations.

3. Set the locating rule and the tolerance zone

   Name the records you must hold before a notice is lodged, the notification route and the response time you work to, and the locating equipment and competence you expect. Then set the tolerance zone: the distance either side of a mark inside which no mechanical digging happens. Say who may authorise a machine inside it, and on what evidence.

4. Name your soil classes and support standards

   Write the classification scheme your competent person uses and the support options it maps to, together with the depth and complexity at which the design leaves the site and goes to an engineer. Add the stand-off distance for spoil and plant, the access arrangement, and how often the classification is revisited once the trench is open.

5. Fix the permit's validity and what voids it

   Decide how long a permit runs, whether it is issued per shift or per phase, and who re-validates it. List what puts the crew outside it: more depth, a wider footprint, a different method, a different support system, or a change to the people named on it. A permit that expires only when the job finishes is not a control.

6. Define the inspection and the stop triggers

   State when the competent person inspects, which is before entry each shift and again after rain, frost or a load placed near the edge, and what they are looking at. Then write your stop triggers: water in the bottom, a slip or a bulge, spoil creeping to the edge, or a service nobody had drawn. Say who may restart the work and against what evidence.

7. Walk it against a real dig

   Take two recent excavations, one that ran to plan and one where something was struck, flooded or deferred, and trace both through the chart. Any step people describe that is not drawn, or drawn but skipped in practice, is the finding worth acting on before you publish it and put it on the permit board.

Frequently asked questions

What are the steps in an excavation permit process?

The job pack shows ground disturbance, and below-threshold work goes ahead under the standard site rules. Otherwise the requester raises the request with location, depth and method, collects the utility records and lodges the dig notice. A locator marks the services, and the competent person judges whether the marks agree with the records, sending a conflict back for a re-survey. Inside the tolerance zone, services are exposed by hand or vacuum. The competent person classifies the soil and decides whether to slope and bench or to shore, taking an engineered design where needed. Edge protection, access and spoil placement are planned, the issuer inspects and issues a time-limited permit, and the crew is briefed. From there it cycles: inspect before entry, work, stop on water, movement or an unmarked service, then record the as-built services, backfill, reinstate and close the permit.

How is an excavation permit different from a permit to work?

A permit to work is the system: it defines which activities need a permit, who may request, issue and accept one, how isolations are certified, how a permit is suspended and handed over at shift change, and how it is closed. An excavation or ground disturbance permit is one certificate issued under that system, and everything specific to it concerns what is underground and what the ground will do. That is why this chart spends its first two phases on records, marking and the tolerance zone, and its third on soil classification and support, none of which appear in a generic permit-to-work flow. On most sites the two are used together: the excavation permit is raised, authorised and closed through the permit-to-work system, and cross-referenced to any other certificate the same job needs, such as a confined space entry or an isolation certificate.

Who is the competent person on an excavation and what do they decide?

The competent person is the one with the training, knowledge and experience to recognise what the ground and the support system are doing, and with the authority to stop the work. In this chart they own five decisions: whether the locator's marks are consistent with the records, whether the dig falls inside the tolerance zone, how the sides will be supported, whether the excavation and its supports are sound before anyone enters, and whether water, ground movement or an unmarked service stops the work. Someone who sees a trench side bulging has to be able to stop the work without asking permission first. In the United States, OSHA defines the term as someone capable of identifying hazards and authorised to take prompt corrective action; equivalent duties exist elsewhere under other names. Name the individuals in your procedure and record how their competence was established.

When does an excavation need sloping, shoring or an engineered design?

Thresholds are set by your own regulations; put them on the chart. In the United States, OSHA's 29 CFR 1926 Subpart P requires a protective system at five feet or more unless the ground is stable rock, or a competent person finds no cave-in indication in shallower ground. Soil is classed as stable rock or Type A, B or C by one visual and one manual analysis. Sloping and benching deeper than twenty feet must be designed by a registered professional engineer; a support system that deep must sit within an engineered design or a manufacturer's tabulated data and limits. Britain's Construction (Design and Management) Regulations 2015 take a duty-based route: practicable steps to prevent collapse, plus inspection by a competent person each shift, after any event affecting stability, and after any accidental fall of material. Treat any depth in a template as a placeholder to replace.

How do you avoid striking underground services when excavating?

No single measure does it, which is why the chart draws four in sequence. Records first: collect the utility drawings and use them as the search plan, not the answer. A notification next: in the United States that is the 811 one-call service, which notifies facility owners to mark their plant; most countries have an equivalent. Then locate on the ground, sweep the area and mark what is found, re-marking when marks fade. Finally safe digging: inside the tolerance zone, expose services by hand or vacuum, dig alongside rather than straight down onto them, using insulated hand tools near cables. When something turns up that nobody had drawn, or is struck outright, the chart stops the work: clear and report a struck service as an emergency; make an unrecorded one safe, notify the asset owner and re-locate, because if one service was missing the rest of the picture is unreliable too.