Scoping vs. Scheduling

By Varun Persaud

Shutdowns and turnarounds are among the most carefully planned events in mining and industrial operations. Every day offline translates to lost revenue, delayed production, and ripple effects throughout the supply chain. Yet despite the importance placed on preparation, shutdown projects continue to overrun both budgets and schedules at an alarming rate.

A global benchmarking study by Independent Project Analysis (IPA) found that 65% of shutdowns experience budget overruns of more than 15%, and nearly half miss their scheduled completion date. The root cause? A fundamental disconnect between what is scoped and what is planned.

This disconnect isn’t just a planning oversight—it’s a structural misalignment between two competing forces. On one side, operations and technical teams define the scope, which outlines what must be done. On the other side, project teams build a schedule around how and when it will be done. When those two elements are misaligned—or worse, developed in isolation—shutdowns fail before execution even begins.

Scope: The Strategic Backbone of the Shutdown

The scope defines the boundaries of the work, including which systems will be affected, which assets will be replaced, which inspections will be conducted, and what upgrades are scheduled. It is the technical expression of why the shutdown is happening.

But in many organizations, the scope development process is informal or reactive. Teams rely on institutional memory, legacy spreadsheets, or tribal knowledge to define work packages. As a result, critical tasks are missed while low-priority items sneak in. More dangerously, scope is often added well into the pre-execution phase, after procurement, workforce planning, and scheduling have already been completed.

In one 2023 turnaround at a copper mine in Chile, over 20 new work packages were added after the schedule had been locked. This required tearing down and rebuilding the entire project timeline, leading to procurement delays, field congestion, and over $2.8 million in change order penalties.

Without a frozen, risk-assessed scope, the schedule is pure fiction.

Scheduling: The Execution Path That Must Match Reality

While scope defines what to do, the schedule defines how to do it. It sequences activities, allocates resources, and establishes a critical path. When done well, it enables efficient field execution, coordinated handoffs, and predictable performance.

But too often, the schedule is built on flawed assumptions:

• That resources will be available when needed
• That all materials will arrive on time
• That crews can work without congestion or conflicts
• That scope won’t change

These assumptions collapse quickly in the field. A 2022 mining shutdown in Ontario showed that only 60% of tasks on the original Gantt chart were executed in the planned sequence. The rest were either delayed, resequenced, or deferred due to unforeseen conflicts, many of which stemmed from scope additions made too late in the process.

In another example, a large energy producer developed a shutdown schedule based on an 85% wrench time per shift. In reality, congested work zones, delayed access permits, and contractor confusion resulted in productivity levels of under 50% during the first five days. By the end of the project, total costs had ballooned by 38%.

A schedule that doesn’t reflect the actual scope and real-world constraints is simply a guess.

The Planning Gap: Why Scope & Schedule Drift Apart

The root problem lies in how many organizations treat scope and scheduling as parallel rather than integrated processes. In theory, planners take a finalized scope and build a schedule. In practice, scopes continue to evolve while schedules are already being finalized. This leads to misalignment in work durations, logic links, resource allocation, and material needs.

This gap is widened when:

• Scope is developed in silos by different departments.
• There’s pressure to “fast-track” the schedule to meet production deadlines.
• There’s no central gatekeeping for late scope additions.
• Execution teams are not involved in the planning process.
• – Lack of specific engineering and construction expertise to guide shutdown sequences and tasks.
• Lack of a consolidated schedule with relevant milestones and successor, predecessor relationships implemented.

The result? Schedules are based on incomplete or inaccurate information and become increasingly disconnected from the real workload.

Case Example: The $40M Turnaround That Missed the Mark

A North American smelter planned a $40 million turnaround with a 28-day shutdown window. The scope was finalized three months before the outage, but leadership allowed for minor additions until the shutdown commenced. These “quick adds” came from maintenance leads, plant managers, and regulatory reviews.

In total, 34 additional work items were added after the freeze. While each was small in cost, collectively they required 14% more labor and 10% more equipment hours. The schedule, however, was never updated to reflect these changes. When execution began, crews were double-booked, materials were late, and contractors weren’t ready for the extra work. The project ultimately ran nine days over and exceeded budget by 22%.

A post-mortem revealed that, despite the execution team flagging the schedule as unrealistic, senior leadership insisted it was “locked.” The planning gap cost the organization millions in idle time, liquidated damages, and lost production.

Bridging the Gap: Best Practices to Align Scope & Schedule

To close the gap between scope and schedule, leading organizations implement an integrated shutdown planning model. This model emphasizes cross-functional input, structured freeze points, and dynamic alignment between what is planned and what is resourced.

Here are four proven strategies:

1. Zero-Based Scope Development: Rather than starting with what was done last time, define the scope from scratch, justifying each item based on asset health, risk, and regulatory need. This prevents scope bloat and ensures alignment with strategic objectives.
2. Schedule-Driven Readiness Reviews: Tie scope approval to schedule readiness. If a work item doesn’t have an execution path, don’t include it. Establish formal readiness gates that require teams to demonstrate how each scope item can be supported with necessary materials, labour, and access.
3. Integrated Planning Workshops: Hold joint workshops with schedulers, technical leads, procurement, and contractors. Build the schedule collaboratively, validating durations and interdependencies. According to Shell’s global turnaround program, this practice alone reduced schedule variance by 18%.
4. Strict Scope Freeze Protocols: Establish a hard scope freeze at least 90 days before shutdown. Any changes made after that point should trigger a formal impact review, including any necessary schedule adjustments. Communicate this policy across all stakeholders and enforce it rigorously.

TMG Aligns Planning with Execution

At TMG, we help organizations avoid the hidden cost traps of poor shutdown planning. Our methodology integrates scope and schedule development from the outset, ensuring that what is planned is executed and that any additions are adequately resourced and, where required, resequenced.

We work directly with technical leads, schedulers, procurement teams, and contractors to develop executable plans grounded in real-world constraints, rather than optimistic assumptions. We enforce governance models that strike a balance between flexibility and control, ensuring that late-breaking needs don’t derail your entire project.

The result? Shutdowns that stay on track, avoid scope-schedule friction, and deliver predictable outcomes.