PRACTICAL RECOMMENDATIONS FOR MANAGING EPCCS PHASES OF STORAGE TANK PROJECTS.

Introduction

Storage tanks constitute critical infrastructure in many industries, including oil and gas, petrochemicals, water, and chemicals.

Their role is fundamental to the safe storage and distribution

of various substances, from raw materials to finished products.

The design, construction, and operation of these facilities require technical rigor and strategic planning to ensure not only operational efficiency, but also personnel safety, environmental protection, and regulatory compliance.

A structured approach is essential to manage the inherent complexity of these projects.

It is in this context that the EPCCS (Engineering, Procurement, Construction, Commissioning & Start-up) phases emerge as a proven methodological framework, allowing the breakdown of a project lifecycle into manageable and interconnected stages.

This article aims to provide practical recommendations and critical reflections for each EPCCS phase specifically applied to storage tank projects. Drawing on 20 years of practical experience and insights from the materials provided and additional research, we will explore key considerations, potential challenges, and best practices to optimize each step.

The goal is to present clear and well-organized arguments, incorporating an argumentation methodology based on critical thinking and personal reflections, to offer a holistic and actionable perspective for industry professionals.

I. Strategic Understanding of Storage Tank Typologies

1.1 Classification and Typologies

From the cartography diagram and tank illustrations, we classify tanks into:

By Location: Aboveground vs. Underground

By Shape: Cylindrical, Spherical, Rectangular

By Pressure: Pressure Tanks vs. Atmospheric Tanks

By Material: Steel/Aluminum, Fiberglass Composite, Concrete, Plastic

Critical Reflection: The choice of tank impacts safety, cost, energy efficiency, emissions control, and operational longevity. For instance, floating roof tanks are ideal for volatile liquids due to their vapor management.

1.2 Floating Roof Options Key types:

External Floating Roof Tanks (EFRT): Best for high-volume storage; cost-effective.

Internal Floating Roof Tanks (IFRT): Greater emission control and safety.

Dome or Suspended Configurations: Enhanced protection from weather and VOC release.

Decision Criteria (Ref. Hervé Yimgna’s Map):

Vapor pressure - Emission control requirements – Cost - Liquid nature (viscosity, solid formation).

II. Engineering Phase

The engineering phase is the starting point of any storage tank project, where initial concepts are transformed into detailed plans and technical specifications.

This is a crucial step that determines the feasibility, safety, efficiency, and regulatory compliance of the entire facility. Rigorous engineering helps minimize risks, reduce long-term costs, and ensure optimal tank performance throughout its lifecycle.

Objective and Key Considerations

The primary objective of the engineering phase is to design a tank that not only meets specific operational requirements (type of product stored, volume, temperature, pressure), but is also safe, durable, and compliant with international standards.

The choice of tank type is a fundamental decision that must be guided by the nature of the product to be stored (volatility, corrosiveness), environmental conditions, and safety requirements.

For example, floating roofs (internal or external) are preferred for volatile liquids to minimize evaporation losses and VOC emissions.

Key considerations in this phase include:

Selecting Tank Type and Materials:

Depending on the fluid properties (vapor pressure, corrosiveness), required capacity, and environmental requirements, the tank type (cylindrical, spherical, rectangular, etc.) and construction material (steel, aluminum, plastic, concrete, fiberglass) are determined.

Material selection is also influenced by chemical compatibility and corrosion resistance, factors essential for tank longevity and safety.

For chemicals, specific purchasing guides are often consulted to ensure the tank material is suitable.

Compliance with Standards and Regulations:

Engineering must imperatively incorporate industry codes and standards such as API (American Petroleum Institute) for petroleum storage tank design, and NFPA (National Fire Protection Association) for fire safety aspects. Guidelines for spacing between tanks and from property lines, as illustrated in the spacing guidelines document, are critical examples of

the application of these standards to minimize the risk of fire spread and facilitate emergency response.

These standards also cover foundation design, vapor control systems, and interfaces with other equipment.

Foundation Design and Site Preparation:

Tank stability directly depends on the quality of its foundation. Engineering must specify the type of foundation (concrete slab, concrete ring, piles) based on soil characteristics, the weight of the tank, and its contents.

Vapor Control Systems and Environmental Aspects: For tanks containing volatile liquids, the design of vapor recovery units (VRUs) or the use of floating roofs is essential to reduce VOC emissions and comply with environmental regulations.

Environmental risk analysis and impact studies are integral components of engineering, aimed at minimizing the risk of leaks and spills.

Personal Reflection

Engineering is, in my opinion, the cornerstone of any storage tank project. This is where the most critical decisions are made, those that will have a profound impact on all subsequent phases. A well-thought-out design, which

anticipates the challenges of construction, procurement, and commissioning, is the best guarantee against delays, cost overruns, and, most importantly, safety incidents.

Key Actions:

Conduct feasibility studies based on fluid type, site topology, and tank typology.

Perform CFD modeling, wind/seismic analysis, and environmental impact assessment.

Integrate digital design tools (e.g., BIM, 3D CAD) and API 650/653 standards.

Critical Point: Early tank typology decisions influence downstream procurement, construction, and OPEX.

III. Procurement Phase

The procurement phase is the process of acquiring the goods, services, and works required to complete the storage tank project. It bridges the gap between the detailed design of the engineering phase and the physical execution of the construction phase. Efficient procurement is essential to ensure that the right quality materials and equipment are available at the right time and at the right price, thus avoiding delays and cost overruns.

Objective and Key Considerations

The primary objective of the procurement phase is to acquire all the components required for the construction and operation of the storage tank, in compliance with the technical specifications defined during the engineering phase.

This includes not only the tank itself (steel sheets, roof elements, etc.), but also valves, pumps, instruments, fire safety systems, coatings, and all other ancillary equipment.

Key considerations in this phase include:

Rigorous Supplier Selection:

Supplier selection is paramount. It's not just about finding the lowest price, but also about ensuring the supplier's reliability, reputation, and ability to deliver materials and equipment that meet quality standards and deadlines.

Request for Proposal (RFP) and supplier qualification processes are implemented to assess their technical skills, experience, and financial strength.

For industrial tanks, it is crucial to consider factors such as the tank's purpose, material, capacity, coating, and certification before purchasing.

Contract and Delivery Time Management:

Once suppliers are selected, clear and detailed contracts are established, specifying technical requirements, delivery schedules, payment terms, and penalties for non-compliance. Proactively managing delivery times is essential to avoid bottlenecks during the construction phase. Delays in procurement can have a significant impact on the overall project schedule and result in additional costs.

Material Traceability and Certification:

To ensure the quality and safety of storage tanks, it is imperative to ensure full traceability of all materials, from their origin to their installation. Certificates of conformity, material test reports, and inspection documents are key elements of this traceability. This is particularly important for critical materials such as steel, whose composition and mechanical properties must meet precise specifications.

Cost and Value Optimization:

Procurement is not limited to purchasing, but also aims to maximize value for the project. This may include seeking innovative solutions, consolidating orders to obtain better prices, or establishing long-term partnerships

with key suppliers. A cost-effective procurement strategy for storage tanks involves careful planning and a long-term needs assessment.

Personal Reflection

The procurement phase is often underestimated for its impact on overall project success. Yet, it is the vital link that transforms engineering plans into tangible components. The quality of materials and equipment procured at this stage directly correlates with the safety and durability of the tank.

Sloppy procurement, motivated solely by short-term cost reduction, can lead to costly and dangerous failures in the future.

My belief is that investing in high-quality materials and reliable suppliers saves money in the long run and provides insurance against operational and environmental risks.

Traceability and transparency in the supply chain are not mere formalities, but pillars of trust and accountability.

Key Actions:

Define specifications for steel grade, aluminum domes, seals, and IFR/EFRT components.

Source from certified vendors (API/NFPA compliant).

Implement digital procurement systems for transparency and traceability.

Risk Control: Ensure materials match design specs to avoid rework or failures during commissioning.

IV. Construction Phase (Construction)

The construction phase is the stage where engineering plans and procured materials take physical form.

This is a period of intense activity on site, requiring precise coordination, rigorous execution, and strict adherence to safety protocols. The quality of construction has a direct impact on the structural integrity, durability, and operational safety of the storage tank.

Objective and Key Considerations

The primary objective of the construction phase is to build the storage tank in accordance with the detailed technical specifications provided by the engineering team, while adhering to safety standards, on time, and within budget. This involves a series of activities, from site preparation to the final assembly of the tank components. Research has highlighted the importance of site preparation and construction methods.

Key considerations for this phase include:

Site Preparation and Foundations:

Before any construction, the site must be thoroughly prepared. This includes leveling the ground, compacting the soil, and providing a solid and stable base for the tank. Whether it is a concrete slab, a concrete ring, or a compacted sand foundation, the base must be able to support the full weight of the filled tank and resist erosion. Improper site preparation can lead to differential settlement, cracks in the tank structure, and long-term stability issues.

Construction Methods:

There are two main methods for constructing vertical flat-bottom tanks:

The traditional (or "bottom-up") method and the jacking (or "top-down") method. The traditional method involves assembling the tank bottom, then installing the shells (wall sections) one after the other, from the bottom up.

The jacking method, on the other hand, begins with the assembly of the roof and the first shell at ground level, then the assembly is lifted by hydraulic jacks to allow the addition of the lower shells. The choice of method depends on several factors, including tank size, site constraints, weather conditions, and safety considerations.

Assembly and Welding:

The assembly of steel plates and other tank components is a critical step that relies heavily on precise and controlled welding techniques. Welders must be qualified, and welding procedures must comply with industry standards (e.g., API 650/653 - CODRES Div 1&2).

Rigorous inspections (radiography, ultrasonics, dye penetrant testing) are performed to ensure weld integrity and prevent leaks. Weld quality is essential for the tank's watertightness and structural strength.

On-Site Quality Control and Safety:

A detailed quality control plan must be implemented throughout the construction phase, including regular inspections of materials, dimensions, welds, and alignment. Construction site safety is a top priority. Strict procedures

must be followed for handling heavy materials, working at height, fire prevention, and confined space management. Ongoing staff training on best safety practices is essential to minimize accidents.

Personal Reflection

The construction phase is the physical embodiment of design. It is where theory meets practice, and where rigorous engineering must be translated into flawless execution. I have always considered building a tank to be an art as much as a science.

Every weld, every joint, every lift must be carried out with meticulous precision. An error at this stage can compromise not only the integrity of the tank, but also the safety of future operations. The emphasis on safety and quality control is not an option, but a moral and professional obligation. Meticulous execution is essential to translate design into reliable reality, ensuring the long-term durability and performance of the installation.

Key Actions:

Site preparation with adherence to spacing guidelines (e.g., 3D for fixed/floating roofs, 5D for cone roofs NFPA/API standards).

Implement rigorous QA/QC on welds, shell plates, roofs, and floating decks.

Ensure environmental protection VOC covers, sealed drains, leak detection.

Human Factor: Train workers in the safe handling of floating deck systems and IFR suspension mechanisms.

V. Commissioning and Start-up Phase

The commissioning and start-up phase is the culmination of all previous stages. It is the time when the storage tank, once constructed, is tested, verified, and prepared for operational use. This phase is critical to ensure that all systems operate as intended, safely, and in accordance with the design specifications. Successful commissioning ensures a smooth transition from construction to operation, minimizing the risk of malfunctions and incidents.

Purpose and Key Considerations

The primary objective of the commissioning and start-up phase is to validate the integrity and functionality of the entire storage tank system before use. This involves a series of rigorous tests, verifications, and adjustments to ensure that each component and integrated system

operates optimally. The information gathered underscores the importance of testing procedures and calibration.

Key considerations for this phase include:

Detailed Commissioning Planning:

Careful planning is essential for this phase. It must include detailed procedures for each test, personnel responsibilities, acceptance criteria, and contingency measures. The plan must cover the verification of all mechanical, electrical, instrumentation, and control systems. The planning must also include pre-commissioning steps, which ensure all systems are ready for functional testing.

Integrity and Functional Tests:

Several tests are performed to confirm the structural integrity and watertightness of the tank. The hydrostatic test, which involves filling the tank with water to verify its strength and detect possible leaks, is one of the most important tests. Leakage tests are also performed on floating roofs and piping systems. Beyond physical integrity, functional tests are conducted to verify the proper functioning of pumps, valves, level detection systems, alarms, and fire safety systems.

Instrument Calibration and Verification:

All measuring instruments (level, temperature, pressure sensors, flow meters) must be precisely calibrated to ensure reliable readings. Automated control systems (PLC, DCS) are also tested to ensure they respond correctly to instrument signals and execute the intended control sequences. Tank calibration, which accurately determines the volume of liquid at different levels, is a fundamental step for inventory management and invoicing.

Operating Personnel Training:

Before startup, the personnel responsible for tank operation and maintenance must receive comprehensive training. This training must cover normal operating procedures, emergency procedures, the use of safety systems, and an understanding of the specific characteristics of the tank and the stored product.

A good understanding of risks and preventive measures is crucial for safe operation.

Personal Reflection

The commissioning phase is the true test of a storage tank project. It's the moment when all the theories, calculations, and construction efforts are put to the test.

I've always been fascinated by the precision required at this stage: every valve, every sensor, every pipe must work in perfect harmony. A botched commissioning can undo months of hard work and jeopardize the safety of the facility.

This is why rigor, patience, and meticulous attention to detail are not only desirable, but absolutely essential.

This phase is crucial to validate the integrity of the system and ensure a smooth transition to operation, thus ensuring long-term reliability and safety.

Key Actions:

Execute hydrotest and helium leak tests.

Calibrate gauges and tank level indicators.

Verify floating roof performance (lift checks, seal gap tolerance, vapor space reduction).

Data Point: Internal floating roofs significantly reduce vapor loss and meet emission regulations.

VI. Start-Up & Operation

Tank startup must be gradual, beginning with the slow filling of the product and carefully monitoring all parameters. Levels, pressures, temperatures, and flow rates are constantly monitored to detect any anomalies.

Continuous visual inspections are performed to ensure there are no leaks or unexpected behaviors. This initial monitoring period is essential to validate tank performance under real-world operating conditions.

Safety Protocols: Establish protocols based on the typographical benefits (e.g., preventing leaks with Type I tanks, facilitating maintenance with Type III tanks) to ensure safe startup.

Performance Monitoring: Monitor tank performance post-startup, particularly for Cryogenic and Underground Storage Tanks, to validate design assumptions.

Key Actions:

Integrate SCADA systems for monitoring tank integrity.

Schedule preventive maintenance: seal inspection, dome corrosion check, weld testing.

Prepare emergency protocols (foam chamber, fire suppression).

Energy Efficiency Note: Dome-roof + IFR configurations optimize vapor management and insulation.

Structured Summary: Storage, Inspection, and Environment

1. Tank Typology & Industrial Use

Storage tanks come in several shapes and uses depending on pressure, temperature, liquid volatility, and environmental requirements.

Common Key Insights

Compliance with Industrial Standards

API 650: Design & construction of atmospheric storage tanks.

API 653: Inspection, repair, and modification during tank life.

ASME VIII: For pressure vessels (e.g., bullets and spheres).

NACE / ISO: Surface protection and corrosion management.

Critical 8-Stage Inspection Lifecycle

Especially vital for floating roof tanks (EFR/IFR) and high-risk tanks:

1. Material Certification - Traceability and compliance.

2. Fit-Up - Alignment of shell joints for leak prevention.

3. Welding - Quality and procedure validation (WPS/PQR).

4. NDT (Non-Destructive Testing) - UT, RT, MT for structural integrity.

5. Hydrotest - Final leak-proof pressure verification.

6. Coating/Corrosion Protection - SA 2.5 blasting + holiday testing.

7. Final Walkdown - Ladder, nozzle, earthing system check.

8. In-Service Inspection - Thickness mapping every 10 years (min).

Volatile Organic Compound (VOC) Emissions

• IFR tanks offer superior vapor control due to fixed + floating roof combo.

• EFR tanks are simpler but more prone to vapor loss.

• Dome-roofed IFRs provide dual containment = better emissions mitigation.

Practical Recommendations for Tank Projects

A. Select the Right Tank Type

Adopt a Structured Inspection Plan (API 653-Based)

Improve Environmental & Energy Efficiency

Do:

• Use geodesic domes on IFRs to improve insulation and vapor capture.

• Install continuous emission monitoring systems (CEMS).

• Follow NFPA/API spacing codes to reduce fire and explosion risk.

Avoid:

• Using EFRs in high-density urban or emission-sensitive zones without secondary containment.

• Applying fixed roof tanks for high vapor pressure fluids.

• Delaying scheduled API 653 inspections early detection saves millions.

Final Recommendations

Prioritize IFR + Dome tanks in sensitive or volatile environments.

Use helium leak detection to complement visual inspections at floating roof rims.

Develop training and inspection protocols that align with API standards and emission mitigation goals.

Conclusion

Storage tank management is a discipline that requires constant attention to quality, safety, and the environment.

By adopting an integrated approach that emphasizes strategic selection, rigorous design, meticulous inspection, and regulatory compliance, companies can not only protect their assets and the environment, but also optimize their operations and ensure their sustainability in a constantly evolving industry.