Identifying Hazardous Substances and Petroleum Products Steps

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A Phase I Environmental Site Assessment (ESA) is a critical step in environmental due diligence, designed to identify potential environmental contamination liabilities associated with a property. Conducted in accordance with ASTM E1527-21, the Phase I ESA focuses on determining the presence or likely presence of hazardous substances and petroleum products through a structured, non-intrusive process.

Unlike Phase II investigations, which involve sampling and laboratory analysis, a Phase I ESA relies entirely on qualitative data collection and professional interpretation. The goal is to identify Recognized Environmental Conditions (RECs)—indicators of contamination resulting from past or current releases, or the potential for future releases.

This post provides a comprehensive overview of how hazardous substances and petroleum products are identified in a Phase I ESA, including:

Records review
Site reconnaissance
Interviews
Storage conditions and quantities
Disposal methods

Understanding Hazardous Substances and Petroleum Products

Before diving into the identification process, it is important to understand what constitutes hazardous substances and petroleum products in the context of a Phase I ESA.

Hazardous Substances

Hazardous substances are defined under environmental regulations and typically include:

Industrial chemicals and solvents
Heavy metals (e.g., lead, arsenic, mercury)
Polychlorinated biphenyls (PCBs)
Pesticides and herbicides
Hazardous wastes

These materials can pose risks to human health and the environment if released into soil, groundwater, or air.

Petroleum Products

Petroleum products include:

Gasoline
Diesel fuel
Heating oil
Lubricating oils
Jet fuel and other refined hydrocarbons

While petroleum is regulated differently than many hazardous substances, it is still a major focus of Phase I ESAs due to its prevalence and potential for contamination.

The Non-Intrusive Nature of a Phase I ESA

A defining characteristic of a Phase I ESA is that it is non-intrusive. This means:

No soil, groundwater, or vapor samples are collected
No drilling, excavation, or testing is performed
Conclusions are based on observation, documentation, and professional judgment

This approach allows for a cost-effective and efficient assessment while still providing valuable insight into potential environmental risks.

Records Review: Building the Historical Context

The records review is one of the most important components of a Phase I ESA. It provides a historical framework that helps identify potentially contaminating activities (PCAs) associated with the property and surrounding area.

Historical Sources

Environmental professionals review a range of historical documents, including:

Aerial photographs
Fire insurance maps (e.g., Sanborn maps)
Topographic maps
City directories
Land title records

These sources help reconstruct the historical use of the property and identify activities that may have involved hazardous substances or petroleum products.

Regulatory Database Searches

A comprehensive regulatory review is conducted to identify listings related to:

Underground storage tanks (USTs)
Aboveground storage tanks (ASTs)
Hazardous waste generators
Spill incidents and cleanup cases
Landfills and disposal sites

This includes searching federal, provincial/state, and local databases.

Identifying Potentially Contaminating Activities (PCAs)

Through records review, environmental professionals identify PCAs such as:

Gas stations and fuel depots
Dry cleaners (solvent use)
Manufacturing facilities
Automotive repair shops
Agricultural chemical storage

These activities are associated with a higher likelihood of hazardous material use and potential releases.

Why Records Review Matters

Records review helps answer key questions:

What activities historically occurred on the site?
Were hazardous materials used or stored?
Are there documented spills or regulatory issues?

This information sets the stage for targeted site reconnaissance and informed interviews.

Site Reconnaissance: Observing Current Conditions

Site reconnaissance involves a visual inspection of the property and adjacent areas. It provides real-time insight into current conditions and helps confirm or challenge findings from the records review.

Visual Indicators of Contamination

Environmental professionals look for signs such as:

Surface staining on soil or pavement
Stressed or dead vegetation
Unusual chemical or petroleum odors
Oily sheens or iridescence on water
Corrosion or leaks from equipment

These indicators can suggest the presence of hazardous substances or petroleum products.

Identifying Infrastructure and Equipment

The site visit also focuses on identifying features that indicate material use or storage, including:

Fill pipes and vent pipes (indicating USTs)
Aboveground storage tanks
Drums and containers
Waste storage areas
Floor drains and sumps

Even if tanks or equipment are no longer present, evidence of former systems (e.g., piping, depressions) can be critical.

Adjacent Properties

Reconnaissance is not limited to the subject site. Adjacent properties are also evaluated for potential off-site impacts, such as:

Nearby gas stations
Industrial operations
Dry cleaning facilities

Contamination can migrate across property boundaries, making this step essential.

Interviews: Filling the Information Gaps

Interviews provide valuable context that may not be available in records or visible during site reconnaissance.

Key Interviewees

Environmental professionals typically interview:

Current property owners
Site operators or facility managers
Past owners or occupants (if available)
Local government officials (e.g., fire department, building department)

Information Gathered

Interviews help uncover:

Historical site uses and operations
Types of materials stored or used
Storage practices and locations
Known spills, leaks, or incidents
Waste disposal practices

Importance of Interviews

Interviews can reveal:

Undocumented activities
Informal practices not captured in records
Institutional knowledge of site conditions

This qualitative information is often critical in identifying RECs.

Storage Conditions and Quantities

A key aspect of identifying hazardous substances and petroleum products is understanding how they are stored and managed.

Storage Practices

Environmental professionals document:

Presence of storage vessels (drums, ASTs, USTs)
Condition of containers (e.g., rust, leaks, labeling)
Organization and housekeeping practices

Improper storage—such as open containers, lack of labeling, or visible leaks—is a strong indicator of potential environmental risk.

Quantities of Materials

While Phase I ESAs do not involve precise inventories, they assess the scale of materials present, such as:

A few small containers vs. numerous large drums
Bulk storage tanks vs. minor quantities

Larger quantities generally correspond to higher potential risk.

Secondary Containment

The presence and condition of containment systems are evaluated, including:

Berms or dikes
Concrete pads
Spill containment pallets

Proper containment reduces the likelihood of releases reaching soil or groundwater.

Why Storage Conditions Matter

Poor storage practices increase the risk of:

Spills and leaks
Chronic releases over time
Environmental contamination

These conditions often contribute to the identification of RECs.

Disposal Methods: Evaluating Environmental Responsibility

Understanding how hazardous materials and petroleum products are disposed of is another critical component of a Phase I ESA.

Waste Management Records

Environmental professionals review available documentation, such as:

Waste manifests
Disposal receipts
Regulatory filings

These records help determine whether materials were handled and disposed of properly by licensed facilities.

Observed Disposal Practices

During site reconnaissance, the EP looks for signs of improper disposal, including:

Illegal dumping
Buried debris or fill of unknown origin
Stained soil in disposal areas
Discharges to storm drains or surface water

Historical Disposal Practices

Older properties may have used practices that were acceptable at the time but are now considered environmentally harmful, such as:

On-site burial of waste
Discharge to unlined pits or lagoons
Use of fill materials from unknown sources

Why Disposal Methods Matter

Improper disposal is a major source of environmental contamination and can lead to:

Soil and groundwater impacts
Regulatory liability
Significant remediation costs

Integrating Findings to Identify RECs

The ultimate goal of identifying hazardous substances and petroleum products is to determine whether RECs are present.

What is a REC?

A Recognized Environmental Condition is defined as:

The presence or likely presence of hazardous substances or petroleum products due to a release, a past release, or a material threat of a release.

Lines of Evidence

Environmental professionals integrate multiple lines of evidence, including:

Historical records
Regulatory data
Visual observations
Interview information

A REC is typically identified when multiple indicators support the likelihood of contamination.

Types of Environmental Conditions

In addition to RECs, the assessment may identify:

Controlled RECs (CRECs): Contamination managed under regulatory controls
Historical RECs (HRECs): Past contamination that has been remediated to acceptable levels

Limitations of the Identification Process

While Phase I ESAs are highly effective, they have limitations:

No direct confirmation through sampling
Reliance on available records and access
Potential gaps in historical information
Subjectivity in interpretation

These limitations reinforce the importance of professional judgment.

The Role of Professional Judgment

Identifying hazardous substances and petroleum products requires:

Experience with industrial and commercial operations
Knowledge of contaminants and their behavior
Understanding of regulatory frameworks
Ability to synthesize diverse information sources

Professional judgment is essential in determining whether conditions warrant further investigation.

When a Phase II ESA is Recommended

If potential contamination is identified, a Phase II ESA may be recommended. This involves:

Soil and groundwater sampling
Laboratory analysis
Quantification of contaminants

Phase II investigations provide the data needed to confirm and characterize environmental impacts.

Conclusion

Identifying hazardous substances and petroleum products in a Phase I Environmental Site Assessment is a comprehensive, multi-step process that relies on records review, site reconnaissance, and interviews. By evaluating storage conditions, quantities, and disposal methods, Environmental Professionals can assess the likelihood of contamination and identify Recognized Environmental Conditions.

Although non-intrusive, the Phase I ESA provides critical insight into environmental risk, helping property owners, developers, and lenders make informed decisions. When conducted thoroughly and interpreted by experienced professionals, it serves as a powerful tool for managing environmental liability and protecting both human health and the environment.

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Identifying Hazardous Substances and Petroleum Products in a Phase I Environmental Site Assessment