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Environmental Assessment & Due Diligence (21E)

Real estate transactions are often high-stakes undertakings. Buying a property without understanding the potential environmental risks and liabilities attributable to former site uses can be very costly, and discovering historic contamination on a property you have purchased becomes an even larger problem. M.G.L. c. 21E Massachusetts Oil and Hazardous Material Release Prevention Act also known as the State Superfund Law is the statute encompassing issues related to the identification and cleanup of property contaminated by releases of oil and/or hazardous material to the environment, widely referenced as merely “21E”.

CSE can help with your environmental site assessment and due diligence needs in a timely and efficient manner. Our team has completed ASTM and AAI compliant Phase I Environmental Site Assessments (ESA) for lenders, brokers, investors, commercial and residential property owners, real estate agents, council, municipal and industrial clients. With our technical depth and experience in the industry, we can also assist in developing strategies to address and resolve identified environmental issues and ensure that environmental risk is minimized.

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CSE’s Environmental Assessment Products and Pricing Guide

Limited Environmental Review

A Limited Environmental Review (LER) is a cost-effective due diligence screening tool for evaluating environmental risk often used by lenders, brokers and investors as part of a tiered approach to environmental risk management. The review provides a limited-scope assessment that does not include a visit by the environmental consultant to the subject property, often used as a cost-effective initial screen of a property to determine the potential for environmental liability at the site, such as contamination from a nearby gas station. If such a concern is identified, then often the evaluation is elevated to a more comprehensive report such as the Phase I ESA, with the cost of the initial report being rolled into the Phase I ESA.

Our review process obtains regulatory documents and files associated with current and historical releases of oil and hazardous materials for a subject property and the surrounding area from databases such as NETROnline, MassDEP, and NHDES.

CSE will interpret the regulatory reports and prepare a short letter report with our findings and recommendations to assist in determining whether further due diligence is required. Database information reviewed may include: waste sites by release tracking number, site name, address, status, and/or chemical type. Typical results include lists of site actions, maps, and links to both electronically submitted and scanned documents.

Information from standard environmental record sources is provided by NETROnline (Nationwide Environmental Title Research, LLC), a comprehensive environmental database information provider containing thousands of environmental records collected from various local, state and federal organizations. Data from governmental lists are updated and integrated into one database, containing information pertaining to Superfund sites, suspected contamination, compliance and violation concerns, permitted sources of toxic vapors and other characteristics that may be harmful.
The Massachusetts Department of Environmental Protection (MassDEP) provides historic and recent reportable release information identified by Release Tracking Numbers (RTNs) within the ‘Waste Sites and Reportable Releases Lookup’ database for sites by site name, address, status, and/or chemical type. Results include lists of site actions, maps, and links to both electronically submitted and scanned documents. Additionally, The ‘File Viewer’ database provides rapidly updated access to files submitted electronically through eDEP and allows complex searches for those files.
The New Hampshire Department of Environmental Services (NHDES) offers a searchable database comprised of environmental information and data compiled by DES programs. OneStop does not provide access to all existing DES data, however, available information includes: sources of environmental interest; GIS data; environmental monitoring data; ordering sampling equipment for environmental testing; permit statuses; and information on local businesses that provide various environmental services, ranging from hazardous waste transportation to water well contractors.

Records Search with Risk Assessment

The Records Search with Risk Assessment (RSRA) is a more comprehensive desktop report that meets SBA Lender and Development Company Loan Programs (SOP 50 10 (5)) Requirements for environmental due diligence at low-risk properties.

The Records Search and Risk Assessment involves:

  • Database search of federal, state and local regulatory agencies
  • Historical record review (fire insurance maps and city directory) of the property and surrounding sites
  • Detailed review by an Environmental Professional, along with a environmental risk rating for your Property

CSE’s experienced environmental professionals can provide an SBA-acceptable RSRA report that quickly and economically provides information needed to determine the environmental risks associated with a property, thereby streamlining the environmental due diligence process. If the RSRA determines that a Phase I ESA is necessary, CSE will apply 100% of the RSRA cost toward the Phase I ESA.

Transaction Screen Assessment

An ASTM Practice E1528-14 Standard Practice for Limited Environmental Due Diligence, or Transaction Screen Assessment (TSA) is quick-turnaround, inexpensive, and effective approach to assess environmental risk of a property. Transaction Screens are usually conducted for commercial properties, residential developments, agricultural properties, and industrial properties for real estate transactions or for bank refinancing.

The purpose of this practice is to define good commercial and customary practice in the United States of America for conducting a Transaction Screen Assessment for a parcel of commercial real estate where the User wishes to conduct limited environmental due diligence (less than a Phase I Environmental Site Assessment). If the driving force behind the environmental due diligence is a desire to qualify for one of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Landowner Liability Protections (LLPs), this practice should not be applied. Instead, the ASTM Practice E 1527-13 for Environmental Site Assessments – Phase I Environmental Site Assessment Process – shall be used.

This practice is intended for use on a voluntary basis by parties who wish to assess the environmental condition of commercial real estate where a Phase I Environmental Site Assessment is, initially, deemed to be unnecessary by the user and the parties do not seek CERCLA LLPs. This practice is intended primarily as a commercially prudent or reasonable approach to conducting an inquiry designed to identify potential environmental concerns in connection with a property.

ASTM Phase I Environmental Site Assessment

An ASTM Phase I performed in accordance with ASTM E1527-13 is generally intended to qualify a buyer for the innocent landowner defense to CERCLA (Comprehensive Environmental Response, Compensation and Liability Act) liability. An ASTM Phase I applies practices that constitute ‘all appropriate inquiry into the previous ownership and uses of the property consistent with good commercial or customary practice’. The goal is to identify the presence or likely presence of any hazardous substances or petroleum products on a property under conditions that indicate an existing release, a past release, or a material threat of a release of any hazardous substances or petroleum products.

Phase I ESAs are conducted for real estate transactions, property development, bank financing, re-financing, and foreclosures, and other in-house proactive audit programs. It is a qualitative approach to determine whether or not oil and/or hazardous materials have affected a property. The process is designed to evaluate both current and historic site uses and to review available records in order to identify recognized environmental conditions (REC). When a REC is identified, CSE has the staff and knowledge to take the project to the next level of assessment; a Phase II ESA which involves the actual sampling of either soil, groundwater, soil gas and/or indoor air. Our goal is to help our clients understand a property’s environmental risks completely and in a clear, unambiguous manner. Our approach meets ASTM guidelines and can be adjusted with additional protocol to satisfy our client’s needs.

A Phase I ESA includes four main components:

  • Records Review: Regulatory records are obtained from federal and state agencies, municipal departments, and standard sources (NPL, CERCLIS, RCRA, etc.) to help identify RECs. The historical land use review includes aerial photographs, city directories, Sanborn fire insurance maps, and interviews with government officials and people familiar with the property and adjoining areas.
  • Site Reconnaissance: a visual reconnaissance of the property is conducted by an experienced environmental professional to verify the findings of the records review and to observe surface conditions for evidence of the use, storage, and release of petroleum and hazardous materials.
  • Interviews: CSE will attempt to conduct interviews with past and present owners/operators, a key site manager, and occupants of the property to obtain information indicating recognized environmental conditions in connection with the property.
  • Report: A single report summarizing the assessment procedures and all relevant information will be prepared for the property, in accordance with the ASTM E1527-13 format. Photographs will be included along with relevant documents obtained during the Phase I ESA, including a Site location map (topographic quadrangle of the subject area), Sanborn Maps, aerial photographs, historical topographic maps, historical street directories, property tax map/card, and an environmental database report. The information and data obtained from the above-referenced tasks will be reviewed, compiled, and presented in a Phase I ESA Report. Evidence of RECs as well as potential releases of petroleum and hazardous materials on the Site or adjacent properties will be noted, if identified. An Opinion provided by a CSE Environmental Professional, in accordance with ASTM E 1527-13 shall be provided regarding the environmental conditions observed at the Site with conclusions presented concerning the presence or absence of RECs in connection with the Site.

In the event that a recognized environmental condition (REC) is identified, CSE has the staff and knowledge to take the project to the next level of assessment; a Phase II ESA which involves the actual sampling of soil, groundwater, and indoor air.

ASTM Phase II Environmental Site Assessment

A Phase II ESA is performed when the Phase I ESA identifies Recognized Environmental Conditions (RECs) and/or recommends further investigation. A Phase II ESA is actually a screening to determine if potential contamination and/or hazardous materials are present to assist in making informed business decisions about the property. The standard of the Phase II ESA is typically defined by the scope proposed by the Environmental Professional and accepted by the client. This allows the scope of work to be tailored to each individual site and situation.

CSE provides quick-turnaround, high-quality Phase II ESAs to provide critical environmental information to property owners and potential buyers alike. The process is a quantitative approach to evaluate Recognized Environmental Conditions (RECs) identified in Phase I ESAs which consists of a more detailed Subsurface Investigation on the property. Analytical data results are compared to state standards in order to establish environmental quality and determine whether or not further assessment activities or remedial action is warranted.

When is a Phase II ESA needed?

In general, a Phase II ESA is needed when previous site usage is identified as: service stations, dry cleaners, automotive and machine shops, manufacturing, hazardous waste storage, etc. Further analysis into the specific site details during the Phase I ESA help determine, if any of these previous uses have created a significant potential for a release or if a known release has occurred.

Many lenders will automatically require a Phase II ESA for a property that has had any of these environmentally-sensitive uses. The subsurface investigation typically includes test borings and installing groundwater monitoring wells with extensive testing. As part of the due diligence process for real estate transactions, a more limited study should be conducted as a screen initially to determine if there is a significant problem. If this is the case, further site characterization may be required or this can help the buyer decide if he wants to go forward with the transaction.

How much does a Phase II ESA typically cost?

The cost for a Phase II ESA ranges greatly, depending on the site specific details. The site specifics include: type of lab analyses required, drilling method needed, access to the subsurface, overhead constraints, groundwater testing required, etc.

Typical due diligence type Phase II ESA studies are in the $7,000 to $10,000 range. In order for us to provide an accurate price quote, we will look at the specific site and develop a strategy to minimize costs and maximize information in order to make accurate conclusions regarding the presence of a significant problem.

CSE’s Phase II ESA Services:


CSE Geologists have successfully completed soil sampling and characterizations for hundreds of sites. To reduce cost and ensure accuracy, CSE typically endeavors to utilize Geoprobe technology, provided by Bronson Drilling to obtain core samples of soil. Once the sample results are received, CSE scientists are able to determine if the sample results collected from the site represent human health and/or ecological risks that require further action.

Soil samples are analyzed by Massachusetts certified laboratories such as Alpha Analytical or New England Testing Laboratory for a select range of contaminant parameters based on site-specific information and/or the suspect environmental findings obtained from the Phase I ESA.


Groundwater monitoring wells are installed within the soil borings to obtain accurate groundwater quality data, groundwater flow direction and gradient. Groundwater remediation & characterization is performed by obtaining grab groundwater samples that are analyzed for a select range of contaminant parameters based on site-specific information and/or the suspect environmental findings obtained from the Phase I ESA. If contamination is present, our geologic experts evaluate the nature, extent, and concentration of the contaminant plume. Following assembly of the data, computer modeling techniques enable CSE scientists to determine the contaminant plume and migration.


If contaminants are found that require removal, CSE can handle all aspects of the project including; development of plans and specifications, obtaining bids from qualified remediation contractors, obtaining agency permits, and managing the remediation from start to finish.


CSE compiles the data and performs an interpretation of analytical results in comparison to applicable cleanup objectives adopted by the Massachusetts Department of Environmental Protection (MassDEP) through a set of regulations known as the Massachusetts Contingency Plan or MCP.

Once environmental findings are confirmed through the Phase II Subsurface Investigation, proceeding steps include establishing the extent of conditions and evaluating an appropriate remedial method. This remediation process may be conducted as directed by the MassDEP Bureau of Waste Site Cleanup following the Site Cleanup Information Roadmap.

Contact us for further information on Phase II ESA Subsurface Site Investigations, the Site Remediation Program, or assistance with your environmental needs.

Vapor Intrusion Assessments

Vapor Intrusion refers to what happens when chemical vapors migrate from the soil or groundwater into a home or other building. Many chemicals that move into buildings this way are classed as volatile organic compounds (or VOCs). The term volatile means unstable, which in turn means these chemicals are likely to exist in gas (aka vapor) form. Vapor intrusion has increasingly become more of an issue mainly due to the MassDEP (and EPA) addition of more commonly found constituents benzene, ethylbenzene and naphthalene typically found in petroleum products.

Because they’re gaseous, VOCs can move easily through spaces between soil particles and tend to migrate from high-pressure to low-pressure areas. Since a basement is probably at lower pressure than the soil underneath, these vapors are likely to enter the basement (or other first level) through cracks in the foundation, walls, or floors. Some heating and air conditioning systems will literally pull the gases into the structure. Once they’re inside, natural airflow and ventilation allow the vapors to spread throughout the building. Vapor intrusion can cause indoor air to become polluted and unhealthy.

What are the risks?

The degree of health risk vapor intrusion poses depends on the type of chemical and concentration of the chemical in the home. The most common sources of chemicals that can cause vapor intrusion problems are gas stations and dry cleaners. For example, a nearby gas station might have a leak or spill from an underground storage tank allowing gasoline to release to the soil and possibly groundwater. Short-term exposure to gasoline-related vapors can cause respiratory irritation, nausea, or headaches, and long-term exposure can contribute to long-term effects such as cancer. Vapor intrusion clearly can cause health risks to families. In addition, vapors might pose a liability issue if they intrude into a workplace.

How do I know whether I have vapor intrusion?

There are several ways to test whether toxic chemicals are entering a building: you can collect soil vapor samples in the ground nearby a structure or in the ground right under your foundation; or you may elect to collect indoor air samples. If you learn that a nearby gas station or industry has had a toxic spill or leak, you might call the owners or government officials to request that they test your home for vapor intrusion.

What should I do?

Landlords, property owners, developers, and investors should take vapor intrusion very seriously. They should include Vapor Encroachment Screenings, Vapor Intrusion Testing in their due diligence activities. If tests indicate that chemicals are intruding into your home or commercial structure, there are several actions you could take. You might seal any cracks in your walls or foundation. Or you could have a mitigation and/or remediation system installed.

CSE has certified environmental consultants who conduct Vapor Encroachment Studies according to the guidance of the ASTM E2600-10 ‘Standard Guide for Vapor Encroachment Screening on Property Involved in Real Estate Transactions‘. A Vapor Encroachments Study is a method for evaluating the potential for a vapor intrusion condition.

If the Vapor Encroachment Study determines that a Vapor Intrusion Condition is likely, a Vapor Intrusion Study may be performed. The preferred method for performing a Vapor Intrusion Study involves the collection of soil vapor samples directly adjacent to or beneath the existing structure or the area of a proposed structure. Soil vapor samples collected are compared to prevailing soil vapor screening levels established by the MassDEP, when available. If soil vapor concentrations exceed established screening levels, then a Human Health Risk Assessment may be necessary to determine site specific risks based on many factors including building characteristics. If the Human Health Risk Assessment finds an elevated risk to human health exists, indoor air sampling, mitigation, or remediation may be necessary.