What is a Phase II Environmental Site Assessment?

When it comes to real estate transactions, land development, and environmental risk management, thorough due diligence is essential.  

One key aspect of environmental due diligence is the Phase II Environmental Site Assessment (ESA). This investigation helps stakeholders—such as property buyers, lenders, developers, and regulatory agencies—determine whether a property is contaminated and what potential environmental liabilities may exist.

Phase II ESAs are conducted after a Phase I ESA indicates the potential for contamination. Unlike Phase I, which is a non-intrusive review of historical records, site inspections, and interviews, a Phase II ESA involves actual sampling and laboratory analysis to confirm the presence of hazardous substances.  

What is a Phase II Environmental Site Assessment?

A Phase II ESA is a detailed environmental investigation designed to determine whether hazardous substances or petroleum products exist at a site in concentrations that could pose a risk to human health or the environment. The assessment typically involves soil, groundwater, and sometimes air sampling, with laboratory analysis providing definitive data regarding contamination.

Key Components of a Phase II ESA:

• ‍Soil Sampling: Soil borings are collected from different depths to assess potential contamination levels.
• ‍Groundwater Sampling: Monitoring wells are installed to check for contaminants in the groundwater.
• Surface Water and Sediment Testing: If applicable, surface water bodies near the site may also be tested.
• Soil Vapor Intrusion Assessment: In some cases, an assessment of volatile organic compounds (VOCs) in soil vapor is conducted to evaluate indoor air quality risks.
• ‍Laboratory Analysis: Samples are sent to certified laboratories for chemical analysis to detect substances such as heavy metals, petroleum hydrocarbons, volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), and other hazardous substances.

The results from these tests help determine whether contamination is present at levels exceeding regulatory thresholds and if remediation or further action is necessary.

When is a Phase II ESA Needed?

A Phase II ESA is typically recommended or required when a Phase I ESA identifies Recognized Environmental Conditions (RECs). RECs indicate the potential presence of hazardous substances due to past or current site activities. Several scenarios commonly trigger the need for a Phase II ESA:

• Real Estate Transactions: Buyers, sellers, and lenders often require a Phase II ESA to understand potential environmental liabilities before a property sale. Lenders may require this assessment to protect their financial interests.
• Regulatory Compliance: Government agencies may mandate a Phase II ESA if a site is suspected of contamination based on historical use (e.g., former gas stations, dry cleaners, or industrial sites).
• Brownfield Redevelopment: Properties that are being repurposed for residential, commercial, or industrial use may need a Phase II ESA to assess contamination risks and qualify for cleanup grants or incentives.
• Lender and Investor Requirements: Financial institutions and investors may require a Phase II ESA to evaluate the environmental risks associated with a property before approving funding.
• Property Development and Land Use Changes: When redeveloping a site for a different use (e.g., converting industrial land into residential housing), regulatory authorities may require environmental testing to ensure compliance with zoning and safety standards.

How a Phase II ESA is Conducted

The process of conducting a Phase II ESA follows industry standards such as those established by the American Society for Testing and Materials (ASTM) E1903-19. The steps generally include:

1. Scope Definition: Environmental consultants review the Phase I ESA findings and determine the necessary scope of investigation, including the number and type of samples required.
2. Field Investigation: Geologists, environmental scientists, and engineers collect soil, groundwater, and air samples using specialized equipment.
3. Laboratory Testing: Samples are analyzed for contaminants based on site history and suspected pollutants.
4. Data Interpretation: The results are compared to regulatory standards to assess risk levels.
5. Reporting and Recommendations: A detailed report is prepared outlining findings, conclusions, and recommendations for remediation (if necessary).

Implications of Phase II ESA Findings

The results of a Phase II ESA can have significant implications for property owners, buyers, developers, and lenders. If contamination is found, it may lead to:

• Additional site investigations (Phase III ESA) to delineate the extent of contamination
• Regulatory involvement, including reporting to environmental agencies
• Remediation efforts, such as soil excavation, groundwater treatment, or vapor mitigation systems
• Potential impacts on property value and financing options

How GPRS Supports the Environmental Sector

As a trusted leader in damage prevention within the environmental sector, GPRS provides dependable results from the initial investigation through delineation, remediation, and project completion.  

With a nationwide network of Project Managers, we are prepared to mobilize quickly for projects across the United States. Utilizing state-of-the-art ground penetrating radar (GPR) scanners, electromagnetic (EM) locators, remote-controlled sewer pipe inspection crawlers and push-fed sewer scopes, acoustic leak detection and leak noise correlators, and more, we Intelligently Visualize The Built World^® to keep your environmental projects on time, on budget, and safe.

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Frequently Asked Questions

What is the difference between a Phase I and Phase II Environmental Site Assessment?

A Phase I Environmental Site Assessment (ESA) is a preliminary, non-intrusive investigation to identify potential environmental risks or recognized environmental conditions (RECs) through records reviews, site inspections, and interviews. If RECs are identified, a Phase II ESA is conducted as a more detailed, intrusive investigation involving soil, groundwater, or air sampling to confirm and characterize contamination. While Phase I focuses on identifying potential risks, Phase II provides concrete data to guide remediation or determine the extent of contamination.

Why do I need to hire a professional utility locating company to locate and mark out all buried utilities prior to beginning an ESA?

Locating buried utilities is essential prior to a Phase I or Phase II Environmental Site Assessment to ensure the safety of field personnel and prevent damage to underground infrastructure during site activities. It minimizes the risk of striking utilities, which could result in costly repairs, project delays, or hazardous situations like gas leaks or electrical incidents. Additionally, accurate utility mapping helps guide subsurface investigations, ensuring that drilling or sampling locations are appropriately cleared and positioned for reliable environmental data collection.