Ground Anchors & Soil Nailing SWMS
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Stressing is the hazard that defines ground anchor work, and it is the one that surprises people. During stressing an anchor holds an enormous amount of stored elastic energy in a steel tendon. If the bond fails, the tendon fails, a wedge does not seat or the head lets go, **that energy is released along the axis of the anchor** — and the tendon, the jack or a wedge is ejected like a projectile, straight back down the line. The rule is absolute and it is the whole reason the task is rated Extreme: **nobody stands, works, passes or stores anything in line behind the jack during stressing.** PPE does not stop an ejected tendon. Position does.
**The second hazard is that these anchors are usually the only thing holding the ground up.** Soil nails and anchors are installed *because* the face would otherwise move, so the crew works at the face, beneath unsupported ground, in the window before the support they are installing exists. Sequence is therefore a safety control, not a program preference: the excavation is taken down in the lifts the geotechnical design specifies, and **each lift is nailed and shotcreted before the next is dug**. Over-excavating one lift ahead to suit a machine is how faces come down on crews. This SWMS covers drilling into a face or batter, tendon and nail installation, grouting, head and bearing plate installation, stressing and proof testing, and lock-off. Authored for New South Wales. Regulator: SafeWork NSW.
Hazards identified
14 hazards covered, sorted by priority.
A steel projectile released along the anchor axis — anyone standing behind the jack is killed
Burial of the crew in the window before the support they are installing exists
Electrocution, gas explosion or fuel release from a service the plan showed as somewhere else
Progressive failure of the retaining structure the anchors exist to hold
Electrocution of the operator and anyone touching the rig — a tendon hoisted vertically is a conductor
Catastrophic entanglement — the string takes gloves, sleeves, hi-vis and hair faster than a person can react, and there is no letting go
Damage to or collapse of neighbouring buildings, roads and services
A surgical emergency from a wound that looks trivial — grout injected under the skin destroys tissue invisibly
Fall injury from a face, a platform, or into the excavation
Head or crush injury to a crew working at the face below
Silicosis from air-drilled cuttings in a formation nobody assessed for silica
Alkaline burns that develop slowly and painlessly at first, and respiratory exposure to dry powders
Hearing loss and vibration injury, concentrated by a face that reflects noise back
Musculoskeletal injury handling long tendons, bars and plates at a face
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Exclude every person from the anchor axis during stressing — the exclusion extends behind the jack for the full projectile path, not a nominal radius — with a physical barrier or deflector and remote or extended-reach pump operation.
- 2Halt stressing immediately on any load anomaly, uneven extension or noise, and never re-stress a failed anchor without engineering assessment.
- 3Excavate strictly in the lifts the geotechnical design specifies and nail and shotcrete each lift BEFORE the next is dug — over-excavating one lift ahead to suit a machine is prohibited.
- 4Inspect the face by a competent person before each shift, after rain and after any vibration event, and treat tension cracks at the crest, seepage, spalling or bulging as a stop-and-evacuate condition.
- 5Ensure all workers hold a current White Card (CPCCWHS1001), with stressing carried out by a competent operator trained on the jack, and drilling and grouting competencies as applicable.
- 6Obtain and interpret all service plans and prove every service by non-destructive means before drilling — including services running BEHIND a face, which a surface plan does not show and a horizontal anchor will find.
- 7Consider adjacent property services, because an anchor extends beyond the site boundary.
- 8Require the geotechnical engineer to specify bond length, grout, tendon and stressing load against the ground actually encountered, with proof testing to the acceptance criteria and load and extension recorded.
- 9Refer any anchor failing acceptance to the engineer — never simply re-stress or accept it — and report any variance from the design assumption before the next lift.
- 10Undertake a dilapidation survey and geotechnical assessment of every adjacent structure, road and service, with instrumentation, amber and red trigger levels, and work stopped at the amber trigger rather than the red.
- 11Enforce the no-touch rule at the rotating drill string — no gloves, no cuffed sleeves, no lanyards, no unrestrained hair — because the PPE that protects elsewhere is the hazard here.
- 12Depressurise and isolate before touching any grout hose or fitting, never clear a blockage or find a leak by hand, and treat any injection injury as a surgical emergency even when the wound looks trivial.
- 13Provide edge protection at the crest for the full perimeter before the excavation reaches 2 m, work from designed platforms rather than off the face, and exclude plant, spoil and material storage from within the zone of influence of the crest.
- 14Consult workers per Section 47 of the WHS Act 2011 (NSW), record it, and review whenever the ground, design, sequence, adjacent structures or method changes, after any incident, or at minimum every 12 months.
Applicable Codes of Practice
The benchmark for ground stability, batter and face control, service location, spoil placement, and the duty to prove services by non-destructive means.
The benchmark for guarding of the rotating drill string, isolation and safe use of the drill rig and the stressing jack.
The benchmark for cement grout, resin and admixtures, including the caustic nature of cement and the exposure standard for respirable crystalline silica.
The design basis for anchored and nailed retaining structures, including anchor and nail capacity, testing and durability.
The relevant installation and testing provisions where the work involves piling plant and grouted elements.
Eyewash and safety shower provision at the grout mixing point and at the face, because cement burns develop slowly and painlessly at first.
High-Risk Construction Work triggered
Anchors and soil nails ARE the temporary support that prevents collapse of the face or batter — the crew installs them in the window before the support exists.
The work is carried out in and against excavations and shafts well in excess of 1.5 m, and the face is unsupported until the lift is nailed.
The drill mast and hoisted tendons operate within reach of overhead lines, and underground electrical assets are credible at every collar.
Drilling into a face penetrates ground that may contain pressurised gas, fuel or chemical lines, including services running behind the face that a surface plan does not show.
Work is carried out on faces, from platforms and at excavation crests where a fall exceeding 2 m into the excavation is possible.
Ground anchor and soil nail installation is high risk construction work under Section 291 of the WHS Regulation 2025 (NSW), so a SWMS must be prepared before work commences (Section 299), kept readily accessible, reviewed as necessary (Section 302), and given to the principal contractor if one is appointed. Part 4.3 Division 3 requires excavation risks to be managed, and an excavation deeper than 1.5 m to be benched, battered or shored, or otherwise controlled on the advice of a competent person. The primary duty of care at Section 19 of the WHS Act 2011 (NSW) extends to occupants of adjacent structures affected by ground movement — an anchor extends beyond the site boundary and so does the consequence of getting it wrong. Energised electrical work is prohibited under Part 4.7 Division 4, sections 154 and 157 unless de-energisation is not reasonably practicable. A face collapse, an anchor ejection, a service strike, an injection injury or uncontrolled ground movement is a notifiable incident under Sections 35–38 and is prosecuted as a Category 1 or Category 2 offence, with the most serious breaches carrying imprisonment for individuals.
Who this is for
- →Geotechnical and specialist foundation contractors installing ground anchors and soil nails to excavations, batters, retaining structures and slopes.
- →Stressing operators and their supervisors, for whom the anchor axis exclusion is the single most important control on the job.
- →Civil and basement contractors excavating against anchored or nailed retention adjacent to existing structures.
- →Geotechnical engineers specifying lift sequences, bond lengths, stressing loads and acceptance criteria.
- →WHS managers and HSE advisors responsible for excavation stability, adjacent structure monitoring and service strike prevention.
What you receive
- ✓A complete, editable Safe Work Method Statement authored for New South Wales — the WHS Act 2011 (NSW), the WHS Regulation 2025 (NSW) and SafeWork NSW as regulator.
- ✓14 identified hazards with initial and residual risk ratings on a 5x5 matrix, each with controls ordered through the full hierarchy — eliminate, engineer, administrative, PPE.
- ✓The stressing control set built on the line of fire: the exclusion extends behind the jack for the full projectile path, and the SWMS states plainly that PPE does not stop an ejected tendon — position does.
- ✓The lift sequence control set treating sequence as a safety control rather than a program preference — each lift nailed and shotcreted before the next is dug.
- ✓Service strike controls that address services running BEHIND a face, which a surface plan does not show and a horizontally drilled anchor will find, including services on adjacent property.
- ✓Adjacent structure monitoring with amber and red trigger levels and work stopped at the amber trigger, not the red.
- ✓The rotating drill string control set — no gloves, no lanyards, no cuffed sleeves — inverting the normal site PPE rule for the reason that inversion exists.
- ✓The full high risk construction work breakdown — temporary support, excavation over 1.5 m, energised electrical, pressurised gas/chemical/fuel lines and falls over 2 m — with the reason each applies.
- ✓Microsoft Word (.docx) format, unbranded, with a PPE matrix, emergency procedures covering ejection, face collapse and injection injury, and a worker sign-on table.
Worked example
An anchor on the third row fails acceptance during proof testing. It takes load, then the extension goes long and the gauge sags, and the operator backs it off. The engineer is in a meeting. The program says the next lift digs tomorrow. The supervisor makes a decision that sounds entirely reasonable — re-stress it and see if it holds — and this time it holds, and everyone moves on. What actually happened is that the bond had failed and the grout was carrying nothing but friction, and the second stress bedded it just enough to read right. The row is now a line of anchors where one of them is holding by luck, and the lift below is dug on the strength of a number that was never real. This SWMS makes that decision the engineer's: any anchor failing acceptance is referred and never simply re-stressed or accepted, load and extension are recorded and issued to the engineer rather than to the site, and no lift is released on program pressure. And the person who backed the jack off did it from outside the anchor axis, which is why he is alive to argue about it.
Related legislation
- Work Health and Safety Act 2011 (NSW) — Section 19 primary duty of care, extending to occupants of adjacent structures affected by ground movement; Section 47 consultation; Sections 35–38 notifiable incidents.
- Work Health and Safety Regulation 2025 (NSW) — Section 291 (high risk construction work) and Section 299 (preparation and content of a SWMS), with review under Section 302.
- Work Health and Safety Regulation 2025 (NSW) — Part 4.3 Division 3 (excavation work): the duty to manage ground collapse, and the requirement that an excavation deeper than 1.5 m be benched, battered, shored or otherwise controlled on competent advice.
- Work Health and Safety Regulation 2025 (NSW) — Chapter 5 (plant) for the drill rig and stressing jack, Part 4.4 (falls) at the crest and face, and Part 4.7 (electrical) including the prohibition at Division 4, sections 154 and 157.
- AS 4678 (Earth-retaining structures), AS 2159 (Piling: Design and installation) and AS 4775 (Emergency eyewash and shower equipment), with the Excavation work Code of Practice.
Frequently asked questions
Why is the exclusion zone behind the jack, not around it?
Because a stressed anchor stores enormous elastic energy in a steel tendon, and if the bond, the tendon, a wedge or the head lets go, that energy releases along the AXIS of the anchor. The tendon or a wedge is ejected like a projectile, straight back down the line — not radially. A circular exclusion of a few metres around the jack misses the actual line of fire entirely, which may extend a long way behind it. The SWMS requires the exclusion to follow the projectile path, a barrier or deflector behind the jack, and the pump operated remotely or at extended reach so the operator is out of line.
Can we get one lift ahead to keep the excavator moving?
No, and this is the single most common cause of face collapses on nailed walls. The nails are what hold the face up; the design specifies the lift height because that is the depth the ground will stand unsupported for the time it takes to nail and shotcrete it. Digging one lift ahead means the crew works beneath a face that is deeper than the design ever assumed, in the window before its support exists. Sequence is a safety control here, not a program preference, and deviating from it is a design change requiring the geotechnical engineer — not a site decision.
The plans show no services behind the face. Is that enough?
No, because a surface service plan does not show what runs behind a vertical face, and a horizontally drilled anchor is aimed straight at it. Anchors also extend beyond the site boundary, so the relevant services include the neighbour's. The control is to prove services by non-destructive means before drilling, in the direction of drilling, and to consider adjacent property. If clearance cannot be established, the hole is relocated by the engineer's design rather than by the driller's judgement.
Grout got on a worker's arm and he says it's fine. Is it?
Probably not, and that is the trap with cement. Wet cement and grout are alkaline, and the burn develops slowly and is often painless at first — the worker genuinely feels fine while the damage progresses under the skin, and by the time it hurts it is a full-thickness burn. Flush with running water for at least 20 minutes, remove contaminated clothing while flushing, and seek medical attention regardless of how it looks. That is why eyewash and safety shower to AS 4775 are required at the mixing point and at the face rather than back at the site shed.