Phase I Environmental Site Assessments and UST Sites
Specialized ESA requirements for properties with underground storage tank risks
A Phase I Environmental Site Assessment (ESA) is the cornerstone of environmental due diligence, but properties with current or historical underground storage tanks require specialized investigation approaches. Understanding the unique requirements for UST-related Phase I assessments is critical for environmental professionals, lenders, and property buyers to properly identify and evaluate contamination risks.
ASTM E1527 Standard and UST Considerations
The ASTM E1527 Standard Practice for Environmental Site Assessments provides the framework for Phase I ESAs, but UST sites require enhanced focus in several key areas:
Enhanced Historical Research
- Sanborn Fire Insurance Maps: Critical for identifying USTs from 1867-1970s
- Aerial Photograph Analysis: Sequential review to track facility changes over time
- Fire Department Records: UST installation and removal permits, inspection reports
- Environmental Database Searches: State UST registries, LUST databases, EPA ECHO
- Chain of Title Review: Property ownership history and business operations
Specialized Site Reconnaissance
UST-focused site inspections look for specific indicators:
- Fill ports, tank vents, and dispenser islands
- Stained concrete, asphalt, or soil discoloration
- Abandoned underground piping or electrical conduits
- Monitoring wells or vapor extraction systems
- Strong petroleum or solvent odors
- Dead or stressed vegetation patterns
UST-Specific Interview Requirements
Interviews are crucial for UST sites and must target key stakeholders:
Current Property Owner/Operator
Knowledge of UST history, removal activities, spill incidents, and maintenance records
Former Owners/Operators
Historical operations, tank installation dates, product types, closure methods
Local Officials
Fire marshal records, building department permits, environmental agency files
Long-term Area Residents
Historical land use, former business operations, known spill incidents
Common UST-Related RECs
Phase I ESAs may identify several types of Recognized Environmental Conditions related to USTs:
Historical Presence RECs
Evidence of former USTs without documentation of proper closure or soil testing
Active UST RECs
Current USTs with compliance violations, monitoring deficiencies, or suspected leaks
Adjacent Property RECs
LUST sites or active USTs on neighboring properties that could impact the subject property
Database Searches and Records Review
UST-focused Phase I ESAs require comprehensive database searches beyond standard federal listings:
Federal Databases
- EPA UST Finder
- ECHO (Enforcement & Compliance)
- RCRIS (Hazardous Waste)
- NPL (Superfund Sites)
State Databases
- UST Registry
- LUST Database
- Spill Incident Reports
- Voluntary Cleanup Programs
When to Recommend Phase II
A Phase I ESA should recommend Phase II investigation when UST-related RECs are identified. Key triggers include:
- Historical records show former UST presence without closure documentation
- Physical evidence of UST infrastructure remains visible
- Database listings show the property as a former or current UST facility
- Strong petroleum odors or visible contamination observed
- Adjacent LUST sites could impact groundwater beneath the property
- Interview subjects report knowledge of spills or releases
Regulatory Compliance Considerations
Phase I ESAs for UST properties must address specific regulatory requirements:
All Appropriate Inquiries (AAI): EPA's AAI rule requires specific qualifications for environmental professionals and documentation standards
State UST Programs: Most states have their own UST regulations that may be more stringent than federal requirements
Innocent Landowner Defense: Proper Phase I documentation is essential for CERCLA liability protection
Lender Requirements: Many financial institutions have specific Phase I requirements for UST-impacted properties
Best Practices for UST Phase I ESAs
- Engage UST Specialists: Use environmental professionals with specific UST experience
- Expand Search Radius: Consider broader database searches for UST-dense areas
- Document Everything: Photograph all potential UST indicators thoroughly
- Interview Multiple Sources: Cross-reference information from various stakeholders
- Consider Seasonal Factors: Snow cover or vegetation can obscure visual indicators
- Plan for Follow-up: Budget time and resources for potential Phase II assessment
Need to research UST history for your property? Search our UST database or learn about cleanup costs if contamination is found.
Frequently Asked Questions
What makes a Phase I ESA different for properties with potential UST issues?
UST-focused Phase I ESAs require specialized historical research including Sanborn maps, fire department records, and UST database searches. They also involve specific visual indicators like fill ports, vents, and stained concrete, plus interviews focused on petroleum storage history.
How long does a Phase I ESA take for a property with UST concerns?
A typical Phase I ESA takes 2-4 weeks, but properties with complex UST histories may require additional time for historical research, especially if multiple former operators or extensive database searches are needed.
What happens if my Phase I ESA identifies UST-related RECs?
If Recognized Environmental Conditions related to USTs are identified, you'll typically need a Phase II ESA involving soil and groundwater sampling. This helps determine if contamination exists and its extent, informing remediation needs and transaction decisions.