When it comes to acquiring commercial real estate, most investors focus on cap rates, cash flow projections, and financing terms. Environmental due diligence, however, is one of the most critical yet frequently overlooked steps in the transaction process. A contaminated property can expose buyers and lenders to enormous financial and legal liability, turning what appeared to be a sound investment into a costly burden. Understanding how Phase I and Phase II Environmental Site Assessments (ESAs) work is essential knowledge for any commercial real estate professional navigating today's market.
What Is a Phase I Environmental Site Assessment?
A Phase I Environmental Site Assessment is a standardized investigation designed to identify potential or existing environmental contamination liabilities associated with a commercial property. Governed by the ASTM International Standard E1527-21, which was updated in 2021 and remains the industry benchmark heading into 2025, the Phase I ESA is conducted by a qualified environmental professional (EP) and does not involve any physical sampling of soil, water, or building materials. Instead, it relies entirely on records review, site reconnaissance, and interviews with owners, occupants, and local government officials.
The primary output of a Phase I ESA is the identification of Recognized Environmental Conditions, or RECs. A REC represents the presence or likely presence of a hazardous substance or petroleum product that has been released into the ground, groundwater, or surface water of a property. Lenders, including most banks, credit unions, CMBS conduit lenders, and SBA-approved institutions, require a Phase I ESA before funding virtually any commercial mortgage. Completing one also provides borrowers with important protections under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), specifically the "innocent landowner" defense.
A typical Phase I ESA includes the following components:
- Review of historical aerial photographs, topographic maps, and Sanborn fire insurance maps dating back to the first developed use of the property
- Examination of federal and state environmental databases for records of spills, underground storage tanks (USTs), or hazardous waste generation
- Physical inspection of the subject property and adjoining properties for visible signs of contamination or distressed vegetation
- Interviews with current and past property owners, occupants, and local government representatives
- A written report summarizing findings, RECs, and recommended next steps
According to the Environmental Data Resources (EDR) 2024 Market Outlook, Phase I ESA turnaround times have averaged between 15 and 20 business days across most U.S. markets, though complex urban properties with long industrial histories can take considerably longer. Costs typically range from $1,500 to $6,000 depending on property size, location, and complexity.
When Does a Phase II Assessment Become Necessary?
If a Phase I ESA identifies one or more RECs, the environmental professional may recommend proceeding to a Phase II Environmental Site Assessment. Unlike its predecessor, a Phase II involves direct physical investigation of the property, including the collection and laboratory analysis of soil, groundwater, soil vapor, and sometimes building material samples. This is where the stakes, and the costs, escalate significantly.
According to the American Society for Testing and Materials, approximately 25 to 30 percent of all commercial properties that undergo a Phase I ESA proceed to some level of Phase II investigation due to identified recognized environmental conditions.
A Phase II ESA is conducted under the ASTM E1903 standard and typically involves drilling soil borings, installing monitoring wells, and submitting samples to a certified laboratory for analysis of contaminants such as petroleum hydrocarbons, chlorinated solvents, heavy metals, and polycyclic aromatic hydrocarbons (PAHs). Results can take anywhere from three weeks to several months, and costs generally range from $5,000 to well over $50,000 depending on the scope and number of sampling locations required.
For commercial real estate transactions, a Phase II finding that confirms contamination does not automatically kill a deal. Savvy buyers and their legal counsel often use contamination findings as leverage to renegotiate purchase prices, require sellers to remediate the site prior to closing, or structure indemnification agreements that allocate liability appropriately. Lenders, for their part, may require remediation to a documented closure standard before funding, or they may require environmental insurance as a condition of the loan commitment.
Lender Requirements and Financing Implications
Environmental risk is taken very seriously by commercial mortgage lenders across all product types. Whether a borrower is seeking a conventional bank loan, a bridge loan, an SBA 7(a) or 504 loan, or a CMBS execution, the lender's environmental policy will come into play. Most institutional lenders follow federal guidelines established by the Office of the Comptroller of the Currency (OCC) and the Federal Deposit Insurance Corporation (FDIC), both of which emphasize environmental risk management as part of sound credit underwriting practices.
SBA lenders are among the most stringent when it comes to environmental reviews. Under current SBA Standard Operating Procedures, a Phase I ESA is required for virtually all real estate-secured SBA loans, and a Phase II may be required based on the findings. Properties with confirmed contamination may be ineligible for SBA financing altogether, or they may require a No Further Action (NFA) letter from the relevant state environmental agency before the SBA will consider approval.
CMBS lenders and life insurance companies also maintain strict environmental underwriting policies, often requiring reliance letters that allow the lender to rely on the Phase I ESA prepared for the borrower. Some lenders require that the ESA be addressed directly to their institution, particularly when a property has a complex environmental history. Working with a commercial mortgage broker who understands these nuances can save significant time and prevent unnecessary delays in the loan approval process.
Best Practices for Borrowers and Investors
Environmental due diligence should never be treated as a checkbox exercise. Investors who approach Phase I and Phase II assessments proactively, rather than reactively, are far better positioned to manage risk and close transactions efficiently. The following best practices can help protect your investment and streamline financing:
- Order your Phase I ESA early in the due diligence period, ideally within the first week following contract execution, to allow adequate time to address any findings before your contingency deadlines
- Hire an environmental professional with demonstrated experience in your specific property type and geographic market, as local regulatory knowledge is invaluable
- Review the scope of the ESA with your lender before ordering to ensure the report will meet their specific reliance and content requirements
- If a Phase II is recommended, engage both your environmental consultant and a qualified environmental attorney simultaneously to understand the legal and financial implications of the findings
- Consider purchasing environmental liability insurance, which can cover third-party claims, cleanup costs, and business interruption related to pre-existing or newly discovered contamination
- Request copies of all historical environmental reports from the seller as part of your due diligence request list; prior Phase I or Phase II reports can accelerate your consultant's work and reduce costs
Environmental due diligence is ultimately an investment in certainty. The cost of a thorough Phase I and, when warranted, Phase II assessment is negligible compared to the potential liability of acquiring a contaminated property without full knowledge of its environmental condition. In a lending environment where lenders are increasingly scrutinizing collateral quality, arriving at the closing table with a clean environmental record is a genuine competitive advantage.
As the commercial real estate market moves through 2025, environmental considerations are expected to become even more prominent in underwriting discussions. Regulatory agencies at the federal and state levels continue to expand the universe of regulated substances, and climate-related site risks such as flooding and wildfire proximity are beginning to intersect with traditional environmental review processes. Investors who build strong environmental due diligence practices into their acquisition workflows today will be far better equipped to navigate the evolving risk landscape of tomorrow.
