Closure Studies: What They Are and Why They Matter

A closure study is one of the most valuable investments an asset owner can make before committing to the end-of-life of a major industrial facility. It is also one of the most commonly deferred. The result of that deferral is usually a project that costs more, takes longer and carries more residual risk than it needed to.

This article explains what a closure study is, what it should contain, and why the timing of the work matters as much as the quality of it.

What is a closure study?

A closure study is a structured technical and commercial assessment of what it will take to retire, decommission, demolish and remediate an industrial asset — and what that process will cost, how long it will take, and what risks it carries.

It is not a demolition plan. It is not a remediation strategy. It is the document that precedes both: the work that defines the end-state, identifies the constraints, tests the options and establishes a credible basis for the decisions that follow.

A well-executed closure study gives an asset owner the information needed to make a sound investment decision, seek board or regulatory approval, develop a procurement strategy and engage the market with confidence. Without it, those decisions are made on assumptions that may not survive contact with the actual asset.

What a closure study should cover

The scope of a closure study varies with the complexity of the asset, but the core elements are consistent.

End-state definition

The study must establish what the site is intended to become. Full demolition to ground level, partial retention, mothballing, land remediation to a defined standard, preparation for redevelopment or transfer — each end-state carries different scope, cost and programme implications. Ambiguity at this stage propagates through every subsequent decision.

End-state definition also requires clarity on what is excluded. Retained structures, ongoing operational interfaces, owner-managed activities and regulatory obligations that sit outside the project scope all need to be identified and documented.

Asset condition and hazardous materials

An honest assessment of the asset's condition is foundational. Structural integrity, the presence and extent of asbestos-containing materials, lead paint, PCBs, process residues, contaminated soils and groundwater all affect methodology, cost and programme. Assumptions about hazardous materials that are not tested against survey data are a common source of budget overruns.

The study should identify what is known, what requires further investigation and what level of uncertainty remains. That distinction matters when developing a cost plan and when deciding how risk should be allocated in the procurement model.

Scope development

A closure study translates the end-state into a defined scope of work. This includes demolition, decommissioning, isolation and disconnection, hazardous materials management, waste handling, remediation, verification and close-out. It also identifies enabling works, temporary works, approvals, owner-supplied information and interfaces with continuing operations or adjacent activities.

Scope gaps at this stage become variations, disputes or unbudgeted costs during delivery. The purpose of the study is to reduce those gaps to a manageable residual — not to eliminate all uncertainty, but to distinguish between uncertainty that can be resolved through investigation and uncertainty that must be managed through appropriate risk allocation.

Programme

A credible programme requires more than a Gantt chart. It needs to reflect approvals lead times, investigation and survey work, enabling activities, operational dependencies, seasonal constraints, contractor mobilisation and the realistic duration of demolition, remediation and verification activities.

Programme is also a cost driver. Extended access restrictions, staged shutdowns and operational interfaces affect contractor overheads and the owner's own holding costs. A closure study that does not address programme realistically will produce a cost plan that does not hold.

Cost estimation

The cost plan developed through a closure study should be decision-grade — that is, sufficiently detailed and well-supported to justify investment approval and to serve as a reference point for procurement. It should separate known costs from contingency, identify the basis of key estimates and make exclusions explicit.

Common gaps in early closure cost estimates include incomplete hazardous materials allowances, underestimated remediation scope, no provision for enabling works or temporary works, and optimistic assumptions about salvage value. A closure study should surface these gaps and address them, or clearly flag where further investigation is needed before the estimate can be refined.

Risk register

A structured risk register identifies the material risks to cost, programme and end-state achievement, assesses their likelihood and consequence, and proposes mitigation or allocation strategies. It should distinguish between risks that can be reduced through further investigation, risks that should be retained by the owner and risks that are appropriate to transfer to a contractor.

The risk register is also a procurement input. It informs the choice of contract model, the structure of tender documents and the evaluation criteria for contractor selection.

Procurement strategy

A closure study should conclude with a recommended procurement approach. That recommendation should be grounded in the maturity of the scope definition, the complexity of the work, the available contractor market and the owner's risk appetite.

A lump-sum contract may be appropriate where the scope is well-defined and the risks are well-understood. A schedule-of-rates or cost-reimbursable model may be more suitable where underground conditions, contamination extent or operational access remain uncertain. Early contractor involvement may add value where the methodology is complex or the programme is constrained.

The procurement strategy is not a formality. It is a risk-allocation decision that shapes the commercial outcome of the project.

When to commission a closure study

The most common mistake is commissioning a closure study too late — after a closure decision has been made, a budget has been approved and a programme has been communicated to stakeholders. At that point, the study can only confirm or challenge commitments that are already in place. Its ability to improve the outcome is limited.

A closure study is most valuable when it informs the closure decision itself, or at least the investment case that precedes it. That means commissioning the work while options are still open: before the end-state is fixed, before the budget is set and before the procurement strategy is determined.

For assets approaching end-of-life, the question is not whether a closure study is needed. It is whether the owner wants to understand the cost and risk before or after they have committed to a course of action.

The relationship between closure studies and ongoing operations

Many industrial assets do not close in a single event. Partial shutdowns, staged decommissioning, equipment removal ahead of full closure and the management of redundant plant alongside continuing operations are common. A closure study needs to account for these interfaces — not just the end-state, but the path to it.

Operational interfaces affect sequencing, access, isolation requirements, safety planning and programme. They also affect cost. Work that must be staged around operating plant takes longer and costs more than equivalent work on a fully vacated site. A closure study that does not address these interfaces will produce a programme and cost plan that cannot be relied upon.

What a closure study is not

A closure study is not a substitute for detailed design, a demolition methodology statement or a remediation action plan. It is the precursor to those documents — the work that establishes the basis on which they can be developed.

It is also not a compliance exercise. A closure study that is commissioned to satisfy a regulatory or governance requirement, without genuine intent to use its findings, will not improve project outcomes. The value of the work comes from the decisions it informs, not from its existence as a document.

Applying closure study findings

The output of a closure study should be a live reference document, not a report that is filed and forgotten. As the project moves from planning to procurement to delivery, the findings should be tested against emerging information, updated where conditions differ from assumptions and used as a basis for evaluating contractor proposals, assessing variations and managing close-out.

Professional Projects Group prepares closure studies for asset owners across Australia managing the end-of-life of refineries, manufacturing facilities, energy infrastructure, defence sites and major industrial property. The work is grounded in direct delivery experience — the kind of knowledge that distinguishes a study that can be acted on from one that looks credible on paper but does not survive the realities of the asset.

Professional Projects Group prepares closure studies for asset owners across Australia managing the end-of-life of refineries, manufacturing facilities, energy infrastructure, Defence sites and major industrial property. Our closure studies are grounded in direct delivery experience — defining the end state, developing the scope, testing the methodology, establishing the cost and identifying the risks before major commitments are made. The result is a study that can be acted on, not one that looks credible on paper but does not survive procurement scrutiny.

If you are approaching a closure decision and want to understand what a structured assessment would involve for your asset, contact us to discuss it.