TerraShield site

TerraShield Mitigates Vapor Intrusion on Former Industrial Site

A former industrial site located in Southern California was targeted for redevelopment and chosen to be developed into a federally funded public site. Historical operations left the original property contaminated with petroleum hydrocarbons and volatile organic compounds (VOCs). In addition to the presence of these contaminants, new buildings constructed in the area are required to feature a vapor intrusion mitigation system due to the presence of methane gas in the soil, which may eventually enter unprotected buildings on the surface. Because of these factors and the completed site’s intended purpose for public use, an effective vapor mitigation system was necessary.

TerraShield application

This case study features the following:

  • The former industrial site required an effective vapor mitigation solution to move the federally funded project forward
  • The consultant determined TerraShield was the safest and most cost-effective vapor barrier system to install at this site
  • The installation of TerraShield was completed on schedule and the site is currently pending closure (NFA)
ca high school

Pre-emptive Vapor Mitigation Protects Students from Potential Exposure

Pre-emptive Vapor Mitigation Protects Students from Potential Exposure

This case study reviews a high school that has been a fixture in its Southern California community since it was built in the 1930’s. Due to onsite pesticide use, a vapor intrusion mitigation system was necessary to protect students and staff. The environmental team responsible for treating the potential vapor intrusion identified the historical use of pesticides on site and voluntarily sought a remedial solution to protect the site’s future occupants. In efforts to protect students and staff against potentially harmful vapor intrusion as a result of historic releases, a vapor intrusion barrier system was proposed as the most appropriate remedial approach. 


This case study features the following:

  • High school is located in an urban Southern California area with more than 3,000 students.
  • Due to onsite pesticide use, a vapor intrusion mitigation system was necessary to protect students and staff.
  • The vapor barrier was applied throughout the 14,000 square foot library building located on-campus.
Former textile mill

Vapor Barrier Speeds Redevelopment of Former Textile Mill

A former textile mill operated from 1926 through 1983. Throughout the years in operation, there were no regulatory guidelines in place regarding the use and disposal of hazardous chemicals used on site. As a result, once operations ceased, the site was classified as a brownfield. The building has been vacant since the early 2000’s and the hazardous environmental conditions have made redevelopment a challenge. However, tax credit financing made it possible for developers to purchase the 24,500 square-foot building in 2015. The developers received $9 million in tax credit financing, making this remediation and restoration project possible. The tax credits included the New Markets tax credits and South Carolina Textiles Communities Revitalization Act.

textile mill case study

This case study features the following:

  • Site owners are pleased that the quick installation of Geo-Seal allowed the project to meet construction timeline goals
  • The support of the state of South Carolina through the tax incentive package made it possible for developers to redevelop this brownfield site into new jobs and businesses for the community
  • The construction and renovations included elements of historic preservation

Retro-Coat Utilized to Prevent Harmful TCE and Chloroform Vapor Intrusion

A former industrial manufacturing facility in Greenville, SC was purchased for redevelopment in 2017. Building improvements were planned to include a warehouse, offices and self-storage units to serve a growing commercial area. Now located within an urban commercial land use area of Greenville, redevelopment plans included converting the industrial warehouse building into climate controlled self-storage units, and renovating the office into an apartment unit and office.

Prior to purchasing the site in 2017, the current site owners entered into a Voluntary Cleanup Contract and Brownfields agreement with the South Carolina Department of Health and Environmental Control (SCDHEC). The Brownfields agreement allowed the site owners to purchase the site while receiving SCDHEC liability protection for existing environmental contamination by agreeing to perform certain environmental assessment, mitigation, or remediation activities.

Vapor Intrusion Barrier South Carolina

This case study features the following:

  • The Retro-Coat barrier and Vapor-Vent system were incorporated into already planned renovations, saving the site owner time and money.
  • Retro-Coat is resistant to both TCE and chloroform and is a wearing surface, rated for foot and forklift traffic.
  • The Retro-Coat system layers cure quickly, reducing building downtime.
  • The combination of Retro-Coat and Vapor-Vent was chosen as a remedial solution to mitigate the risk of harmful vapor intrusion.
Spray applied core

MonoShield™ Installed At Site Of Former Hazel Park Raceway

This case study reviews a site at the former Hazel Park Raceway, located in a designated Opportunity Zone, which was established by the US Federal Treasury to encourage businesses to invest in blighted properties by providing tax incentives. These tax incentives made the redevelopment of the Hazel Park Raceway possible. In the course of evaluating potential remedial options for the 650,000 square foot warehouse facility (Tri -County Commerce Building #2), consulting firm SME approached Land Science, a division of REGENESIS, to incorporate a vapor barrier system to address the harmful vapor intrusion.

This case study features the following:

  • With MonoShield offering a more reliable, cost-effective solution, the project was assured of meeting milestones and staying on time and on budget.
  • Hazel Park welcomed the economic development and the promise of future jobs coming to the community through this key redevelopment project.
  • The support of the city of Hazel Park, the state of Michigan, the Michigan Economic Development Corporation (MEDC), and the Michigan Department of Environment, Great Lakes, and Energy (EGLE) has made it possible to redevelop the Hazel Park Raceway.
  • After a successful application at nearby Liberty Park, MonoShield was chosen as the best vapor intrusion mitigation solution for the Tri-County Commerce Building #2.
MonoShield install

Construction Time Reduced with New Vapor Barrier System

This case study reviews a brownfield site that posed multiple remediation challenges with a variety of known contaminants including arsenic, lead, and methane. To build on the site would require a unique foundation along with a vapor intrusion mitigation solution. Working with the developer Ashley Capital’s environmental consulting firm SME, Land Science recommended MonoShield, a new and innovative vapor intrusion mitigation system. This modified asphalt-nitrile vapor barrier system is designed to withstand even the toughest vapor intrusion conditions, ensuring a safe environment for years to come. SME chose to be the first to install MonoShield because it provided the best chemical resistance for this brownfield site and would also save the client time and money.

webinar on MonoShield

This case study features the following:

  • Liberty Park is being transformed from underutilized into a property that will bring jobs and growth to the community.
  • MonoShield has the efficiency of a prefabricated barrier system and the flexibility and responsiveness of a spray-applied component for sealing penetrations, wall terminations, and seams.
  • MonoShield is both time — and cost-efficient; it can be installed 30-40% faster than alternate plastic sheeting or HDPE systems.
  • Cooperation among numerous stakeholders: The Michigan Department of Environment, Great Lakes, and Energy (EGLE), Ashley Capital, SME, Oliver Construction, Land Science, and S&H Waterproofing.

Retro-Coat Applied to Former Jazz Club Ensures Protection from Vapor Intrusion

Subsurface contamination caused by chlorinated volatile organic compounds (CVOCs) beneath a former jazz club posed a direct risk to the indoor air quality for a Renton, Washington property. The CVOCs had migrated beneath the property from a neighboring dry cleaning operation resulting in a vapor intrusion (VI) issue. When environmental consultant Maul Foster Alongi performed a cost analysis of different vapor mitigation and remediation approaches, it was found that the Retro Coat™ Vapor Intrusion Coating System would provide an excellent solution at about a third of the cost less than other remedial approaches.

Seattle vapor intrusion mitigation

This case study features the following:

  • How Maul Foster Alongi achieved 33% cost savings compared to alternative remedial approaches
  • Indoor air quality evaluation of TCE and other VOCs
  • Retro-Coat application details
  • Vapor mitigation performance results and indoor air quality findings after the installation of Retro-Coat

Retro-Coat Helps Speed Real Estate Transaction

Project Highlights

  • Retro-Coat functioned as a vapor intrusion mitigation membrane as well as a long-lasting coating for the basement level, accomplishing two of the owner’s goals with one product.
  • Retro-Coat was chosen as the most feasible and effective treatment due to compatibility with pre-existing methane mitigation system components.
  • Retro-Coat is resistant to harmful methane gas intrusion and is a wearing surface, meaning no additional concrete protection is necessary.
  • The updated vapor intrusion mitigation system allowed for the new tenants to move in quickly.
  • Retro-Coat is applied without any odor and cures quickly, reducing building downtime.

Project Summary

An office building located on the San Francisco Peninsula was left vacant for multiple years. The building is located on top of a capped landfill which is a known methane producer. After a recent change in ownership, it was important for the new owner to make the necessary improvements to the building so that new tenants could move in quickly. One of these improvements was to update the vapor mitigation system to ensure the tenant’s safety from any harmful vapor intrusion.

The owner enlisted the expertise of Langan to update the vapor mitigation system. Langan proposed using Retro-Coat Vapor Intrusion Coating System because of its proven resistance to harmful vapors and its durability. The owner was thoroughly pleased with this application because it accomplished two goals with a single product: it mitigated the harmful vapor intrusion and provided a durable coating for the floor of the basement level. Retro-Coat’s multi-functionality saved the site owner time and money.


Technology Description

Retro-Coat Vapor Intrusion Coating consists of chemically resistant materials which protect existing structures from the threat of contaminant vapor intrusion. Retro-Coat was developed by experienced vapor intrusion specialists and is proven to resist the most aggressive chemical vapors. This technology acts as a protective barrier eliminating the need to remove the existing slab and when combined with in situ treatment, it can greatly lower remediation costs.



Retro-Coat consists of chemically resistant materials which will protect this structure from the threat of contaminant vapor intrusion, specifically methane gas. Retro-Coat finishes to a high gloss, easy-to-clean surface that is impervious to vapor and moisture transmission. Additionally, Retro-Coat withstands foot traffic and industrial settings. It was significant to have a highly durable coating system in place because the tenants plan to use the basement level to house large computers and heavy technological equipment.

The site owner has been very pleased with the outcomes from Retro-Coat. The building’s basement level has a highly durable coating and most importantly, the vapor intrusion mitigation system is now highly effective.

Former St. Louis Chemical Plant Incorporates Geo-Seal and Vapor-Vent for Redevelopment Project

Project Highlights

Chemical Plant Geo Seal
70,000 Square Feet of Geo-Seal and Vapor-Vent Applied to Prevent Harmful Vapor Intrusion
  • Geo-Seal applied to over 70,000 square feet of commercial space
  • Redevelopment project is projected to create more than 1,000 new jobs in the St. Louis area

Project Summary

A former Solutia chemical plant, located in St. Louis, Missouri, in between the Mississippi River and St. Louis, required environmental remediation for safe redevelopment. The developers plan to turn the brownfield site into industrial and warehouse space. The redevelopment project is projected to significantly impact the area by providing more than 1,000 jobs.

The environmental remediation process included removing contaminated soil and treating contaminated water, as well as protecting buildings from possible vapor intrusion. In order to prevent vapor intrusion, the contractors installed over 70,000 square feet of Geo-Seal with a vapor ventilation system. Geo-Seal and Vapor-Vent were installed in between the soil pad and the foundation of the new buildings. Installing Geo-Seal, a composite and chemically resistant membrane system, effectively seals all entry pathways into the building preventing harmful vapor intrusion. In conjunction with Geo-Seal, Vapor-Vent, a ventilation system, allows for the natural buildup of underground vapors to be safely diverted and diffused above ground. The vapor barrier system ensures safety from vapor intrusion for this brownfield redevelopment.

Technology Description

Geo-Seal is a vapor intrusion barrier which is placed between the foundation of the building and the soil pad. Geo-Seal is a three part system which combines two layers of chemically resistant high-density polyethylene (HDPE) with a spray applied core layer as well as a venting system.

Vapor-Vent is a low-profile vent system used in lieu of slotted PVC pipe. Through either passive or active ventilation, Vapor-Vent can safely regulate the diffusion underground vapors. This technology provides cost savings through its quick installation and its proximity of the vent to the barrier.


The use of Geo-Seal with Vapor-Vent ensures that the buildings will be safe from harmful vapor intrusion. Following the installation of the Geo-Seal and Vapor Vent vapor barrier system, the new buildings met safety and environmental regulatory requirements ensuring a safe working environment for future tenants.



Response Action Outcome Issued by LSRP for New Jersey Child Care Center Following Successful Installation of Geo-Seal®

Project Highlights

lsrp vapor intrusion solutions

  • New Jersey Department of Health Issued Safe Building Interior Certification for Child Care Center.
  • Over 45,000 sq feet of Geo-Seal installed, ensuring a high level of vapor protection and meeting strict regulatory standards.
  • The vapor barrier met the requirements of the New Jersey Vapor Intrusion Technical Guidance and allowed construction to remain on schedule.
  • Indoor air sampling was conducted in conjunction with the close out of construction activities verifying the vapor barrier was performing as specified. The developer was able to open the child care center on time, generating revenue from the leasehold tenants.

Project Summary

The former building site was used for numerous commercial and industrial operations. Lisko Environmental was contracted by the client to remediate the site in order to make way for a new mixed-use building. During this site’s redevelopment, the building site was razed in order for a new building to be constructed in the same footprint. This new building is a mixed use development for two tenant spaces: trampoline park and child care facility. During the initial phases of redevelopment, an off-site source of cVOC’s was identified and suspected to be migrating towards the site. After further inspection, the developers found that there were dissolved phase cVOC’s present beneath the site at levels well above the NJDEP’s groundwater vapor intrusion screening levels.

In order to prevent harmful vapor intrusion, the new building was designed and constructed with 45,000 square feet of Geo-Seal and a passive vapor mitigation system. This Vapor Mitigation System (VMS) was installed in conjunction with construction activities in order to meet construction milestones in a timely manner. The VMS is passive consisting of a vapor barrier and sub-slab vent piping extending above the roof line fitted with turbine caps. No other mechanical components such as motors or vacuum blowers were necessary at this time, however this system could become an active VMS if needed in the future.


Geo-Seal is a vapor intrusion barrier which is placed between the foundation of the building and the soil pad.
Geo-Seal is a three part system which combines two layers of chemically resistant high-density polyethylene (HDPE) with a spray applied core layer. This system prevents harmful vapors from permeating through the slab allowing developers to ensure a healthy indoor environment. Installing a Geo-Seal system offers developers a lower total cost
to remediate and allows projects to move forward in a timely manner.
site details lisko


The Geo-Seal vapor barrier was installed and smoke tested by Edgeboro, International Inc., a licensed Geo-Seal installer. With this barrier in place, the Licensed Site Remediation Professional (LSRP) issued a Response Action Outcome (RAO) letter for the Site and the developer was issued a Safe Building Interior Certification which meets the requirements of the New Jersey Department of Health and the Department of Children and Families Services allowing the child care facility to obtain applicable licenses and the developers to generate revenue from the tenants with out delays caused by environmental problems.

About Lisko Environmental

liskoWith 20 years of consulting experience, Lisko Environmental specializes in the assessment, remediation, and management of environmental liability. Lisko Environmental assists clients to assess their environmental liability, address the problems and close out the issues as quickly and as efficiently as possible. Lisko Environmental acts as their client’s advocate. Serving clients from Maine to Virginia, Lisko Environmental works in both the private and public sector, on Brownfields, Greenfields and everything in between.