Skip to main content
What Is A Phase 2 Environmental Site Assessment?

What Is A Phase 2 Environmental Site Assessment?

Phase I and subsequent Phase II Environmental Site Assessments (ESAs) are federally standardized procedures that are used by an Environmental Professional (EP) to study the history and current usage of the property and analyze any potential resulting impacts on the environment.

Phase II ESAs are developed and performed in conformance with the scope and limitations of the Standard Practice for Phase II Environmental Site Assessments – ASTM Practice E 1903-11. The EP who performed the Phase I ESA for a property may recommend that a subsequent Phase II ESA be performed in order to close data gaps that may have prevented the EP from forming a conclusive opinion regarding the presence or risk of hazardous waste or petroleum contamination relative to the property.

The objectives of this second stage of ESA are to obtain sound, scientifically valid data concerning actual property conditions identified as Recognized Environmental Conditions (RECs) in a Phase I ESA report through the collection of groundwater, soil, and/or soil vapor samples for laboratory analysis. The results of laboratory analysis of any samples collected during a Phase II ESA are compared to acceptable values set by State and Federal environmental agencies based on site usage and exposure pathways.

Phase 2 Environmental Site Assessment: Why Do I Need It?

Understanding the purpose of a Phase II ESA as it pertains to the health and safety of site personnel, the impact on the environment, and limiting property owner liability is crucial to determining if it is the right step to take toward accomplishing your goals for your property or business.

Validation of the information collected or the resolution of any data gaps encountered during a Phase I ESA by the analysis of samples collected during a Phase II ESA can inform the property owner or potential buyer so that they can protect themselves and their personnel from exposure to hazardous contamination. It establishes existing environmental conditions occurring at the property prior to the purchase of a property or occupation by a tenant, alleviating the User’s liability for any RECs identified in the Phase I ESA and validated in the Phase II ESA. This is especially prudent for owners and leasers of commercial or industrial properties.

After confirming the presence of any hazardous substance or petroleum product contamination in relation to the property, the EP can work with the property owner, responsible party, or state/federal agencies to develop a remediation strategy for site cleanup.

Contrary to common perception, the findings of Phase I and Phase II ESAs do not necessarily impact property values negatively. Although it would seem that the discovery of contamination at a property would decrease the property value, the environmental remediation and restoration of a previously contaminated property may actually boost the property value as it has been certified by an EP as safe for occupation.

What’s Involved?

There are eight components of a Phase II ESA as defined in ASTM Practice E 1903-11, which an EP follows to develop a plan to meet the objective(s) determined by the User of the ESA and the EP:

1) Formulate the Question

The User and EP work together to develop what question(s) the Phase II ESA will seek to answer (e.g., Did the usage of the property as a gas station for 40 years cause contamination in the soil and groundwater?).

2) Identify the Areas of Concern

The EP will determine which areas onsite will be investigated, based on all information reasonably ascertained through the Phase I ESA, in order to achieve the stated objectives of the assessment (e.g., The area around the tank farm).

3) Develop a Conceptual Model

The conceptual model of a property describes which contaminants are likely to have been released to the onsite soil and groundwater and where they have likely traveled since the time of release. The EP determines the contaminants of concern, the mode of release to the environment (e.g., Petroleum contamination from a deteriorated storage tank), and the determination of which environmental media and where the contaminants are likely to have concentrated (e.g., The soil around the leaking storage tank).

4) Plan the Sampling and Analysis

The EP must plan to collect samples from environmental media at locations relevant to the assessment objectives based on the conceptual model (e.g., Sample the soil around the tank farm). The samples must be analyzed by a state-certified analytical laboratory for the contaminants of concern. The sampling and analysis plan must be reproducible such that another EP would be able to repeat the sampling and analysis and produce similar results.

5) Perform the Sampling and Analysis

The EP must carry out the sampling and analysis plan, noting any observations of physical conditions revealed during the investigation and any issues which may impede the EP from performing the sampling and analysis as planned.

6) Validate the Conceptual Model

Following the analysis of the samples by a state-certified laboratory for the contaminants of concern, the EP must evaluate the analytical results to determine if the information obtained during the investigation is consistent with the conceptual model and if conclusions can be drawn which satisfy the objective(s) (e.g., Soil samples containing petroleum contamination confirm that the property usage as a gas station resulted in contaminated soil onsite).

If the results do not support the expectations from the conceptual model, then the EP cannot draw conclusions to satisfy the objective(s), the conceptual model may need to be revised, and additional sampling may need to be performed (e.g., The soil was not found to be contaminated, but the groundwater was, which could indicate that the contamination came from another source and mobilized in the groundwater).

7) Develop Conclusions

Based on the findings of the Phase II investigations, which are consistent with the conceptual model, the EP must develop conclusions that specifically answer the questions and satisfy the objective(s) of the Phase II ESA.

8) Prepare a Phase II ESA Report

The EP must finally develop a report of the Phase II investigations detailing the objective(s), findings, interpretations of findings, and conclusions, as well as a description of the conceptual model, the investigations performed, observations made, and data obtained in such a way that other EPs may be able to reproduce the assessment and obtain similar results.

How Long Does It Take?

AOTC’s team of trained and experienced EPs can complete a small-scale Phase II ESA within 20 business days! More complex, high-risk, or high-acreage properties may take longer due to the complexity of the scope, site access issues, complex conceptual models, or large property areas.

How Much Does It Cost?

A typical small-scale Phase II ESA performed by an AOTC Environmental Professional is affordable without sacrificing quality at $15,000 or less! More complex, high-risk, or high-acreage properties are priced to suit our client’s needs while ensuring a high-quality report to protect our client’s health and liability.

Contact an Environmental Site Assessment Company Today

Do your goals for your property and liability include a Phase I or Phase II Environmental Site Assessment? At AOTC, we offer a wide range of environmental site assessment and remediation services to accelerate accomplishing those goals. Contact AOTC today to schedule your comprehensive Environmental Site Assessment with one of our highly trained and experienced Environmental Professionals.


Can we send you our next blog post?