Exploring the Phase II Environmental Investigation Process

When developing or purchasing a property, ensuring it is environmentally sound is critical — not just for regulatory compliance but also for safeguarding health and maintaining property value. 

If a Phase I Environmental Site Assessment (ESA) reveals known or potential contamination on a site, the next step is to conduct a Phase II Environmental Investigation, also referred to as a Phase II ESA. This comprehensive investigation digs deeper, providing clarity about potential environmental risks and offering the key information you need to move forward with confidence. 

Let our experts walk you through:

• The purpose and steps of a Phase II ESA

• The common contaminants it identifies

• What to expect from the findings

What Is a Phase II Environmental Site Assessment?

A Phase II Environmental Site Assessment is a detailed investigation process designed to confirm or rule out potential soil, groundwater, or vapor contamination on a property. This investigation is initiated when a Phase I Environmental Site Assessment (ESA) identifies recognized environmental conditions (RECs) — indicators that contamination may be present. 

Unlike a Phase I ESA, which is limited to reviewing historical records and a cursory site inspection, a Phase II ESA involves physical sampling and laboratory analysis to determine whether contamination exists and, if so, its severity.

Phase II ESAs are a critical step for ensuring that properties comply with environmental standards without exposing developers or owners to long-term liabilities.

The Purpose of a Phase II ESA

The main objective of a Phase II ESA is to provide in-depth information about potential contamination identified in the Phase I ESA. 

Our environmental investigations help answer essential questions, including:

• Is contamination present, and if so, what kind?

• How widespread is the contamination?

• What are the regulatory and cleanup implications?

By answering these questions, a Phase II ESA protects developers, property owners, and financial institutions by reducing uncertainties and uncovering liabilities before properties change hands or projects move forward.

Detailed Steps in a Phase II ESA

A Phase II Environmental Investigation typically follows a structured approach with multiple steps:

1. Site Investigation

The process begins with a detailed review and investigation of the property. A team of environmental consultants identifies specific areas on the site where contamination is most likely to occur based on historical records, prior reports, and the Phase I Environmental Site Assessment (ESA) findings. 

These areas, often referred to as Areas of Concern (AOCs), become the focal points for further testing.

Example: A former gas station site may prioritize areas near underground storage tanks or fueling areas for investigation, as these are potential sources of petroleum leaks.

2. Sampling & Analysis

Once the AOCs are identified, fieldwork begins. 

This phase includes:

• Soil Sampling: Collecting soil samples at specific depths to test for hazardous substances like petroleum hydrocarbons, heavy metals, or pesticides.

• Groundwater Sampling: Installing monitoring wells to collect groundwater samples is often critical for identifying contamination that may migrate beyond the property boundaries.

• Vapor Sampling: Testing soil gas for volatile organic compounds (VOCs) that could accumulate in subsurface areas and pose risks to indoor air quality.

These samples are then sent to laboratories accredited for environmental testing. Analytical techniques, such as gas chromatography or mass spectrometry, detect and quantify contaminants with precision.

3. Data Interpretation

After lab results are returned, the real work begins. 

Environmental specialists evaluate the data to determine:

• The types and concentrations of contaminants present.

• Whether contamination levels exceed regulatory thresholds.

• The extent and scale of contamination across the site.

Through this process, investigators develop a clearer picture of whether contaminants pose a risk to human health and the environment.

Common Contaminants & How They Are Assessed

Phase II investigations may detect a range of contaminants depending on the site’s history and previous uses. 

Some of the most commonly assessed contaminants include:

• Petroleum Hydrocarbons: Often found on former gas stations or industrial sites; tested for in soil and groundwater.

• Heavy Metals: Contaminants such as lead, arsenic, and mercury may be found on sites with a history of manufacturing activities.

• Volatile Organic Compounds (VOCs): Common in dry cleaning operations or industrial solvents, these compounds are often detected in soil gas or groundwater.

• Pesticides and Herbicides: These may be present on agricultural lands or former farm properties.

Each contaminant requires specific testing protocols, and results are compared to state and federal environmental standards to assess their significance.

Reporting & Documentation: What to Expect

After a Phase II ESA, the investigator compiles findings into a detailed report, which typically includes:

• A summary of the investigation process, from site evaluation to sampling and analysis.

• Maps and figures showing sample locations, areas of concern, and the extent of contamination.

• Lab results indicating the types and concentrations of contaminants.

• Conclusions about the level of environmental risk.

• Recommendations for next steps, such as remediation, monitoring, or further assessment.

This report is critical not only for clients but also for regulatory approvals, lenders, and other stakeholders.

Implications of Findings & Next Steps

If the Phase II ESA confirms contamination, the implications depend on the type and severity of the findings:

1. No Action Required: If the results show contamination below regulatory thresholds, the project can proceed as planned without further mitigation.

2. Remediation Needed: When contamination exceeds thresholds, a Phase III ESA (Remediation Planning) may be necessary to outline strategies for cleanup.

3. Ongoing Monitoring: For some properties, continuous monitoring may be required to track contamination levels over time.

Regardless of the outcome, a thorough Phase II ESA provides a roadmap for clients to make informed decisions about risk management and regulatory compliance.

Phase II ESAs With Terradyne Are Essential for Your Project

Completing a Phase II Environmental Investigation is about more than just regulatory compliance. It’s about protecting your investment, minimizing risk, and ensuring the health and safety of future property users. 

By identifying and addressing environmental concerns early with Terradyne, you can:

• Streamline the approval process.

• Avoid costly surprises during construction.

• Build community trust through responsible land use.

When it comes to environmental assessments, thoroughness is everything. Don’t leave it to chance. If you're planning a project or property transaction, our team is here to assist with environmental site assessments and geotechnical engineering services. 

Contact us at 817-952-7217 or request a consultation to ensure your environmental assessments are handled with expertise and care.