What Is a Phase II Environmental Site Assessment?
A Phase II Environmental Site Assessment (ESA) is a critical step in environmental due diligence for commercial and industrial properties. This assessment is typically initiated when a Phase I ESA, performed under ASTM Standard E1527-21, identifies potential or actual environmental contamination, known as Recognized Environmental Conditions (RECs).
A Phase II ESA plays a key role in environmental risk management by determining the presence of hazardous substances, petroleum products, or other environmental contaminants in soil, groundwater, and other media.
When Is a Phase II ESA Required?
A Phase II ESA is triggered when the findings of a Phase I ESA suggest the possibility of hazardous materials or petroleum products being present on-site. The objective is to confirm or rule out contamination and determine whether further environmental remediation is necessary.
Examples of Potential Environmental Concerns Identified in a Phase I ESA (Triggers for Phase II):
Petroleum & Chemical Storage
- Former or existing underground storage tanks (USTs) or aboveground tanks (ASTs)
- Spills or leaks from fueling stations, vehicle repair shops, or generator tanks
- Historical use as a gas station or dry cleaner
Hazardous Material Use or Disposal
- Use of solvents, degreasers, or industrial chemicals (e.g., TCE, PCE, VOCs)
- Evidence of chemical drums, waste dumps, or buried materials
- Improper hazardous waste storage or disposal practices
Industrial & Manufacturing Activities
- Past use as factories, metal plating shops, foundries, or textile plants
- Documented wastewater discharge or emissions to soil or groundwater
- Legacy impacts from chemical-intensive processes
Building-Related Hazards
- Suspected asbestos-containing materials or lead-based paint
- PCB-containing equipment (e.g., old electrical transformers)
- Potential vapor intrusion from volatile chemicals beneath the building
Regulatory & Historical Red Flags
- Listing in federal/state databases such as CERCLIS, RCRA, or Brownfields sites
- Historical aerial imagery showing rail lines, tanks, or industrial facilities
- Property was part of or adjacent to a Superfund site
Contaminant Migration From Off-Site Sources
- Chlorinated solvents migrate through groundwater from a nearby former or active dry cleaning facility
- Petroleum Hydrocarbon migration from an upgradient gas station
- Volatile organic compounds (VOCs) from a neighboring industrial facility may travel through the subsurface as soil gas and migrate into structures via vapor intrusion
Key Steps in the Phase II Environmental Site Assessment Process
1. Planning and Scope Development
The process starts with developing a detailed scope of work. This involves:
- Identifying areas of concern (AOCs)
- Selecting contaminants of potential concern (COPCs)
- Defining appropriate sampling strategies
This foundational step ensures that the assessment is targeted and effective.
2. Environmental Sampling and Laboratory Analysis
Qualified environmental professionals collect and analyze samples of:
- Soil and groundwater
- Soil vapor
- Surface Water
- Potentially building materials
Samples are tested in certified laboratories to determine contaminant levels and compare them to regulatory thresholds.
3. Data Interpretation
Laboratory results are interpreted by experts to assess:
- The extent of contamination
- Risk to human health and the environment
- Whether the site meets applicable screening levels or cleanup standards
4. Phase II ESA Reporting
A detailed Phase II ESA report is compiled, including:
- Field sampling methodology
- Analytical results
- Comparison to regulatory limits
- Recommendations for further action, such as remediation or risk management
Why a Phase II ESA Is Important
- Risk Management: Identifies and mitigates environmental liabilities before a property acquisition or development.
- Regulatory Compliance: Ensures conformance with local, state, and federal environmental regulations.
- Provide stakeholders—developers, lenders, attorneys, and investors—with crucial environmental data to support strategic decisions.
Who Needs a Phase II ESA?
- Commercial real estate buyers
- Industrial facility owners
- Municipal redevelopment agencies
- Brownfield project developers
- Financial institutions conducting environmental risk assessments
Schedule a Phase II ESA with GEL Engineering
A Phase II Environmental Site Assessment is a vital process for managing environmental risks in commercial real estate, industrial redevelopment, and property transactions. By identifying contamination early, it protects public health, ensures compliance, and safeguards financial investments.
At GEL Engineering, our environmental professionals specialize in Phase II Environmental Site Assessments and brownfield redevelopment support. Whether you're buying, selling, or redeveloping a site, our team ensures your decisions are backed by clear, defensible data.