Bund Inspection for Australian Site Managers: Provider Comparison

Commission a bund-integrity assessment by mapping every containment boundary, separating leakage from capacity and compatibility limits, and agreeing the evidence, repair, retest and disposal scope before appointment.

Map the complete containment boundary

Build the quote schedule from the chemical inventory, asset register and containment drawings—not simply a count of bund walls. List each liquid, tank, drum and IBC, then identify vessels sharing a containment area. Under the SA EPA’s guidance, interconnected tanks are treated as one tank with their volumes combined.[2]

Include valves, filters, sight gauges, vents and other ancillary equipment. The SA EPA’s guidance says this equipment should be within the bund so discharges are contained.[2] Mark the following features on a drawing or photograph:

• wall and floor penetrations, pipework and earthing systems;
• construction and movement joints;
• sumps, drainage openings and valves;
• chemical-resistant linings and previous repairs; and
• porous construction, including Besser-block walls.

The SA EPA’s guidance identifies these features as potential sources of cracks, gaps, damaged linings or other containment weaknesses.[2]

Give each physically separate containment area its own identifier. Record the jurisdiction, stored substances and potentially applicable standards because the SA EPA’s guidance is state-specific and says bunding should be used for the storage of all liquids except rainwater.[2] Confirm the governing edition rather than copying a reference uncritically: the SA document lists the 2004 edition of the flammable and combustible liquids standard, while Entexol refers to the 2017 edition.[2][5]

Separate leakage from other containment limitations

A bund can show no obvious leakage and still be inadequate. Classify integrity findings separately from capacity, reduced usable volume, chemical compatibility and spill interception.

Potential leakage or structural findings include cracks, missing or shrunken joints, damaged linings, porous Besser blocks, penetrations, drainage holes and pipework or earthing systems compromising the boundary.[2] The SA EPA’s guidance says an open bund remaining empty after heavy rain may indicate poor sealing; this is a warning sign, not a quantified leak-test result.[2]

• Capacity: Assess tank dimensions and displacement by other tanks and foundations separately from leakage. As South Australian examples rather than national defaults, the SA EPA’s guidance specifies net capacity of at least 120% of the largest bulk-storage tank, or 133% for flammable liquids.[2] For a bunded tank or drum compound with automatic sprinklers, the guidance specifies capacity increased by a volume equal to at least 20 minutes of sprinkler output or to 133% of the largest tank, whichever is greater.[2]
• Reduced usable volume: Record rainwater, previous spills, rubbish, pallets and stored containers. The SA EPA’s guidance indicates these can reduce effective capacity and contribute to overtopping without proving leakage.[2]
• Chemical compatibility: Check the floor, walls and lining against every contained liquid. The SA EPA’s guidance says bund walls and floors should be impervious to each liquid and notes that acidic materials can attack concrete and damaged chemical-resistant linings can compromise containment.[2]
• Spill trajectory: Consider whether an elevated leak could pass over the wall. The SA EPA’s guidance suggests measures such as a splatter shield or tank-to-wall separation normally equal to half the tank height.[2]

Agree the method and preparation before testing

Do not assume filling the bund is suitable. The SA EPA’s guidance and the cited Entexol and MEnD pages do not prescribe one Australian test method, level, duration, allowable leakage rate, calibration requirement or retest procedure.[2][3][5]

Require the proposal to define:

• the inspection sequence and visual or non-destructive methods;
• the proposed test medium, level and duration;
• instruments, calibration evidence and acceptance criteria;
• environmental and operational controls; and
• the response to leakage, movement or another unsafe condition.

Agree how joints, linings, sumps, pipework and penetrations will be exposed. The SA EPA’s guidance recommends supported pipework routed above bund walls rather than through them and removal of materials obstructing inspection.[2] Require inaccessible areas to be recorded rather than treated as inspected.

Access controls must reflect the layout. The SA EPA’s guidance says confined-space requirements may apply near tanks or where bund walls exceed 1.5 metres.[2]

Entexol vs MEnD

Compare both providers against the same three dimensions.

Entexol

• Inspection scope: Entexol describes testing for new and existing industrial containment systems across Australia, including leak detection, deterioration and structural-integrity checks.[5]
• Reporting: Its cited page describes a post-assessment report covering condition, findings, areas requiring attention and maintenance recommendations.[5]
• Remediation support: The cited page states that recommendations are provided but does not state whether remedial design or works quality control is available.[5]

MEnD

• Inspection scope: MEnD describes visual and NDT containment bund and lining integrity surveys for mine sites, process plants and storage facilities.[3]
• Reporting: Its cited page describes asset-condition assessment and concrete, steel and coating inspection capability.[3]
• Remediation support: MEnD offers remedial and lining specifications and quality-control services for new and existing facilities.[3]

Based on the providers’ descriptions, Entexol is suited to a brief focused on dedicated bund testing and optional oil/water-separator assessment, while MEnD is suited to lining surveys, remedial specifications or quality control during works. This does not establish comparative performance.[3][5]

Specify the report evidence

Do not accept a broad pass/fail conclusion. Require separate findings for observed leakage, structural condition, capacity, chemical compatibility, reduced usable volume and interception of elevated leaks.[2]

• Inspection record: Identify each asset and containment boundary, inspection date, personnel, weather, pre-existing liquid level and completed preparation.
• Test record: State the method, instruments, test level, start and finish times, acceptance criteria and results.
• Defect register: Give each defect a unique identifier, precise location, description, severity rationale and supporting photograph or measurement.
• Limitations: List inaccessible or obscured areas, assumptions, deviations and matters outside scope. Do not present these areas as having passed.
• Actions: Separate immediate controls, planned maintenance and further investigation.

Entexol says its reports document condition, findings, areas requiring attention and maintenance recommendations.[5] The more detailed evidence schedule above is a buyer-defined procurement safeguard, not a universal format established by the SA EPA’s guidance.[2]

Separate repairs, retesting and disposal

Limit the initial appointment to the agreed inspection, testing and report. Put temporary controls, permanent repairs, lining work, additional testing and post-repair retesting behind separate written approvals.

• Show each item’s scope, price and program separately.
• Identify who may approve emergency and non-emergency variations.
• State who will set the retest method and acceptance criteria.
• Define how a failed or inconclusive result affects charges and scheduling.

MEnD describes remedial and lining specifications and works quality control, but these services should not be treated as part of an inspection unless included in the quotation.[3] Separate commercial approvals are procurement controls rather than requirements stated by the SA EPA’s guidance or the cited provider pages.[2][3][5]

Control rainwater, test water and spilled liquid

Do not import UK drainage practice into an Australian scope. The UK HSE page describes a low-point manual valve kept closed when not in use, whereas the SA EPA’s guidance says bund drain valves should not be installed and collection sumps should not connect to stormwater or sewer.[1][2]

The SA EPA’s guidance says potentially contaminated rainwater must not enter stormwater.[2] Its published South Australian pathways include:

• suitable onsite reuse;
• collection by an authorised liquid-waste contractor;
• irrigation with approval;
• sewer discharge with SA Water Trade Waste approval; or
• an approved septic-tank effluent disposal scheme.[2]

The guidance says spilled or released liquid may be reused onsite where appropriate; otherwise, it should be collected and disposed of by an authorised liquid-waste contractor.[2] Before testing, allocate responsibility and approval for liquid characterisation, pumping, transport and disposal.

Choose against one written checklist

Score each proposal against the same requirements:

1. Boundary completeness: Are all assets, penetrations, linings and inaccessible areas identified?
2. Method: Are the test level, duration, instruments and acceptance criteria defined?
3. Reporting: Are conditions, defects, photographs and other evidence specified?
4. Limitations: Are exclusions and access constraints disclosed?
5. Commercial controls: Are repairs, retesting and liquid disposal subject to separate approval?

What to confirm with each provider

The cited Entexol page states that oil/water separation functionality assessment is available; the cited Entexol and MEnD pages do not publish prices, quotation structures, other detailed test parameters, site-specific availability, contract or cancellation terms, independent comparative results or a standard report-evidence format.[3][5]

• total inspection and reporting price, assumptions and exclusions;
• test method, level, duration, instruments and acceptance criteria;
• report format and supporting photographs or measurements;
• availability for the site and proposed program;
• contract, variation and cancellation terms;
• repair, retest and quality-control options; and
• responsibility for test water and contaminated-liquid disposal.

References

1. Secondary containment – HSE (hse.gov.uk)
2. Liquid storage Guidelines Bunding and spill management Updated May 20161 (sa.gov.au)
3. Capabilities (mend.com.au)
5. Bund Testing for Compliance & Environmental Protection | Entexol (entexol.au)