Environmental site assessment (phase I & II)
Environmental Site Assessments (ESAs) are structured investigations aimed at identifying, evaluating, and addressing potential environmental liabilities associated with property. They are a foundational component of environmental due diligence, supporting property transactions, redevelopment planning, and risk awareness / management. Phase I & II ESAs are intended to identify potential environmental concerns and evaluate subsurface conditions using standardized practice and scientific principles.
AA GeoEnvironmental provides technical review and quality-control support for Phase I & II ESAs to help ensure that conclusions are technically sound and accurately documented.
Phase I ESAs are non-intrusive, records-based, and observational assessments that identify property-related Recognized Environmental Conditions (RECs). The main objective is to facilitate All Appropriate Inquiries (AAI) in accordance with CERCLA, providing liability protection for property owners, lenders, and investors.
ESAs typically include:
Review of historical land use, property records, and databases
- Federal, state, tribal, and local environmental databases.
- Historical aerial photographs and topographic maps.
- Sanborn maps, chain-of-title, and land-use history.
Environmental liens and activity use limitations (AULs).
Site reconnaissance and visual observations
- Current and former uses with contamination potential.
- Aboveground and underground storage tanks (ASTs/USTs).
- Waste handling areas and drainage features, drums, stained soil, stressed vegetation.
Interviews with knowledgeable parties
- Current and past owners or occupants.
- Property managers and local government officials (when applicable).
Evaluation of Environmental Conditions
- RECs – presence or likely presence of hazardous substances or petroleum products.
- Historical RECs (HRECs) – past releases addressed to regulatory closure.
- Controlled RECs (CRECs) – known contamination managed under controls.
Our roles focus on the review of Phase I ESA findings, assessing the extent to which conclusions are substantiated by the information at hand, and pinpointing possible technical limitations or data gaps, excluding the determination of RECs.
Phase II ESA is an intrusive investigation conducted when Phase I ESA reveals RECs. The objective is to confirm the presence, nature, and extent of contamination through environmental sampling and subsequent analysis. This may include:
Sampling Plan Development
- targeted investigation design based on RECs, CSM, and screening criteria.
Field Investigation
- Soil borings and sampling.
- Groundwater monitoring well installation.
- Soil vapor or indoor air sampling.
- Surface water and sediment sampling.
- UST/AST integrity assessments.
Laboratory Analysis
- samples are analyzed for site-specific contaminants such as petroleum hydrocarbons, VOCs/SVOCs, metals, pesticides, PCBs, PAHs, and PFAS (where applicable).
Data Evaluation
- Comparison to federal and state cleanup criteria.
- Delineation of contaminant extent.
- Refinement of the CSM.
- Assessment of exposure pathways and receptors.
AA GeoEnvironmental conducts a comprehensive review and interpretation of Phase II ESA data and reports, highlighting the scientific accuracy of sampling methodologies, analytical results, and conclusions. This is accomplished by applying principles from geology, hydrogeology, environmental chemistry, contaminant fate and transport, statistical data analysis, and the development of conceptual site models (CSMs). This integrated approach ensures that conclusions are rooted in site specific conditions, rather than broad generalizations.
Our reviews emphasize scientific consistency and clarity, not on issuing legal or regulatory determinations.
What this Service Is
- Technical review and interpretation of ESAs.
- Quality-control support for due-diligence documentation.
- Scientific evaluation of data, assumptions, and conclusions.
- Relevant to redevelopment and planning purposes.
What this Service Is Not
- Performance of Phase I or Phase II field investigations.
- Field sampling and laboratory testing associated with Phase II ESAs.
- Issuance of legal opinions or AAI certifications.
- Regulatory approval or compliance certification.
- Environmental insurance underwriting or risk guarantees.
Clients retain responsibility for regulatory compliance, legal determinations, and
transactional decisions.