Retro-Coat

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.

Retro-Coat

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
UST site

PetroFix Pilot Study Leads to Full-Scale Application

This case study reviews a former bulk petroleum storage facility where a groundbreaking application of PetroFix™ Remediation Fluid, a micro-scale carbon suspension with soluble electron acceptors, is successfully treating petroleum hydrocarbons to IDEM standards. REGENESIS worked with Patriot Engineering and Environmental to develop a remediation solution using PetroFix, which is uniquely designed to address petroleum hydrocarbon contaminants. The site was considered a viable candidate for the beta test, due to the high contaminant levels and provided a good test of the product’s performance at high concentrations. REGENESIS and Patriot agreed to move forward with the development of the beta test with the intention of evaluating its possible full-scale use following the results of the test. The promising results from the beta test and 12 months of post-injection monitoring indicate PetroFix to be a viable remedial option for this site.

This case study features the following:

  • Beta test of PetroFix provided promising results leading to a full-scale application
  • At just one month post-injection, the petroleum VOCs and gasolinerange organics were essentially eliminated from the groundwater and remain so at nine months
  • PetroFix remedial solution is designed to remediate petroleum contamination completely at the lowest total cost to closure
  • Collaborative remediation success between Patriot, Microbial Insights, and REGENESIS
Retro-Coat case study

Retro-Coat Helps Speed Real Estate Transaction

An office building located on the San Francisco Peninsula 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 update the vapor mitigation system to ensure the tenant’s safety from any harmful vapor intrusion. Engineering and consulting firm 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.

Retro-Coat case study

This case study features the following:

  • Retro-Coat functioned as a vapor intrusion mitigation membrane as well as a long-lasting coating for the basement level
  • 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
Treatment of PCE Contamination

Real Estate Transaction Requires Fast-Acting Treatment of PCE Contamination

Treatment of PCE ContaminationThis case study reviews a multi-tenant commercial plaza in the greater Boston area that required remediation of tetrachloroethylene (PCE) contamination in groundwater where a combined remedy approach used at delivered accelerated results using PlumeStop®, BDI Plus® and HRC®.

Due to the owner’s objective to sell their property, a multi-tenant commercial plaza in the greater Boston area required remediation of tetrachloroethylene (PCE) contamination in groundwater associated with historical operations. Because contamination had been identified during due diligence, it was very important to implement a time-effective remediation strategy with minimal disruption to the various operating businesses. Wilcox & Barton, Inc. chose a combined remedial approach to treat the PCE contamination. This included liquid activated carbon (PlumeStop), an enriched, microbial consortium (BDI Plus), and an engineered, hydrogen release compound (HRC).

This case study highlights:

  • Due to the high-traffic and operational hours at this site, injections were performed from 10pm-7am in January.
  • The speed in which Wilcox & Barton, Inc. addressed the contaminants was crucial for the site owners to achieve their goal of marketing the property for sale.
  • Site engineers innovatively included heating systems, additional lighting, and warming facilities to ensure that the remedial agents stayed in their liquid form and to provide necessary amenities to the injection specialists.
  • The combined remedy approach of PlumeStop, BDI Plus, and HRC was selected amongst other remediation strategies for its fast-acting capabilities and its effectiveness in completely dechlorinating contaminants.
CGRS case study

Innovative In Situ Application of PetroCleanze Uses Horizontal Wells

This case study reviews an innovative remediation design at a site that is using two horizontal wells which will administer a total of four injection events, with enhanced fluid recovery (EFR) events being performed before and after each injection. BTEX contamination and free-phase product from a petroleum release was discovered in the groundwater at an active gas station in Colorado. After previous remediation attempts from prior consultants, CGRS, Inc., Paragon Consulting Group, Inc., the Colorado Division of Oil and Public Safety (OPS), and REGENESIS® collaborated to create a design that would successfully remediate the persistent groundwater contamination and free-phase product.

CGRS case study

This case study features the following:

  • Innovative design and creative solution using horizontal wells to apply PetroCleanze and minimize daylighting
  • The horizontal well system allows for the active gas station to continue to conduct business without disruptions
  • Staying open during remediation efforts saved gas station owners an estimated $8,000 per day
  • PetroCleanze was successfully applied despite the challenging lithology and shallow bedrock
aerospace site

Combined Remedy Treats TCE Plume at Aerospace Site

aerospace site remediationThis case study reviews an aerospace manufacturing facility in Southern California that required remediation for a deep and heavily impacted Trichloroethene (TCE) plume. The extensive depth and size of the plume contributed to the difficulty facing remediation efforts, with much of the contaminant plume extending offsite. Alta Environmental and REGENESIS began developing an approach to remediate this site in 2012. After conducting pilot tests, they concluded that Enhanced In Situ Bioremediation (EISB) technology was both cost-effective and feasible for successful remediation of this site. The observation wells continue to be sampled quarterly and are displaying successful reductions in cVOCs.

Case study highlights:

  • Combined remedy was three times the cost savings vs. alternative remedial technologies being considered
  • Completed the application event ahead of schedule
  • Successful reductions in cVOCs observed

In Situ pilot remediation of gasworks impacted groundwater, Stockholm, Sweden

Introduction

In the north-east of Central Stockholm, a historical industrial site was earmarked for redevelopment. Part of the site comprised a former gasworks, where historical operations have caused a complex mix of contaminants to impact the surrounding soil, groundwater and shoreline sediments.

The large site is due to be redeveloped in a series of parcels including a road, industrial park, residential homes and schools. Remediation is required to ensure the human health risk is removed as part of the restoration of the site. The impacted groundwater also represents an environmental risk and requires treatment. Risk assessments were used to determine that remediation was required to a depth of 20m BGL. The geology of the site is heterogeneous, comprising a shallow made ground, a clay layer and underlying coarse sands.

The sands are highly impacted with a range of gas works contamination included creosote NAPLs and high levels of benzene. The saturated clays are also impacted with dissolved phase contamination. Due to contaminants, concentrations and superficial geologies, a range of remedial methods would be required to ensure the most appropriate was used in each scenario. Therefore, RGS Nordic engaged REGENESIS to design a series of pilot tests utilising several in-situ methods. The results from these trials would then be used to shape the full-scale remediation strategy for the entire gasworks site area.

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Combined In Situ Remediation Approach and Planning

REGENESIS proposed a pilot-scale combined remediation approach comprising:

  • Enhanced desorption using PetroCleanze to target high concentrations of soil-bound contaminants of concern (COC’s) in the sands,
  • In Situ Chemical Oxidation (ISCO) using both RegenOx and PersulfOx to target medium to high dissolved phase and soil-bound PAHs in the sandy soil, and
  • Enhanced aerobic degradation using ORC-Advanced to target the low dissolved phase benzene and naphthalene concentrations in the clay.

Results

Groundwater samples were collected 3-4 months after the application of REGENESIS remediation products, see graphs 1 to 3. The results are displayed below

Enhanced Desorption using PetroCleanze

>95% reduction in dissolved phase benzene was achieved with the addition of PetroCleanze. The treatment for PAHs was found to be less effective, primarily due to the low baseline PAH concentrations which were below the optimum treatment concentration range for PetroCleanze.

Graph 1– Effect of PetroCleanze application on dissolved Benzene concentrations

ISCO using RegenOx and PersulfOx

>90% reduction in dissolved phase benzene and PAHs was observed using PersulfOx. In the RegenOx trial, dissolved benzene concentrations were found to decrease by 80%, while PAH levels increased slightly, potentially due to large volumes of desorbed COCs being released into groundwater post-treatment.

Enhanced Aerobic Biodegradation using ORC-Advanced

A sustained reduction in Naphthalene and benzene (despite suspected influx into the test area) was achieved using ORC-Advanced in the saturated clay.

Graph 2– Effect of PersulfOx application on PAH concentrations

Conclusion

  • A wide range of contaminant concentrations were treated effectively using a combined in-situ remediation approach.
  • Substantial reductions in COC concentrations were achieved despite the challenging geological setting.
  • The results from the pilot tests show that all areas of the gasworks site can be successfully remediated in-situ using REGENESIS remediation products, providing significant cost savings when compared with conventional techniques

Graph 3– Effect of ORC-A application on PAH concentrations

ZVI Applied To Remediate DoD Superfund Site

Combined Remedy Effectively Treats 1,2-DCA and TCE at Tinker Air Force Base

This case study reviews the remediation of dichloroethane (1,2-DCA) and Trichloroethylene (TCE) using colloidal zero valent iron (ZVI) at Tinker Air Force Base, a major United States Air Force base located in Oklahoma City, Oklahoma. The remediation included an application of emulsified vegetable oil (EVO), an aqueous suspension of colloidal zero valent iron (MicroZVI Precursor), with small amounts of fertilizer and B12. Typically, zero valent iron cannot be applied through well systems. However, due to the small particle size of the zero valent iron, this application was successfully applied through the existing wells. At 3 years post-injection, the contaminant levels remain near zero with the presence of ethene indicating continuous biodegradation.

This case study features the following:

  • Successful application of colloidal zero valent iron through well system
  • At 3 years post-injection, the presence of ethene signals active biodegradation
  • Aqueous suspension of colloidal zero valent iron effectively reduced contaminant levels

Significant Reduction in VOCs Achieved at Rail Site

This case study reviews a contaminated rail site in Canada that had released chlorinated solvents in groundwater. WSP conducted a pilot test at the site to assess the applicability of a brand-new technology that optimizes delivery of amendments using hydrocolloids. The pilot test would determine the applicability of a passive treatment barrier using PlumeStop and AquaZVI. A combined remedy approach was chosen because it optimizes the use of colloidal activated carbon and zero valent iron, allowing for the highest treatment efficiency at the lowest possible cost. After conducting the pilot test, data for samples collected within the treatment barrier indicated significant contaminant concentration decreases in groundwater and saturated soil.

This case study features the following:

  • First application of PlumeStop® and AquaZVI™ globally
  • Despite wintery weather conditions at the Rail Site in Northern Quebec, the amendment delivery and distribution was successful
  • Over 95% decrease in dissolved and saturated soil VOC concentrations
  • Thorough data analysis including ISMs and CSIA confirmed definite contaminant degradation

Pilot Test Conducted to Remove PFAS Risk

This case study reviews a pilot test to remove PFAS risk via an in situ colloidal activated carbon barrier at Camp Grayling in Crawford County, Michigan, a large year-round military training center operated by the Michigan Army National Guard (MIARNG). Colloidal activated carbon was selected because of the expected rapid reductions of PFAS by removal from the dissolved mobile phase, as well as its expected lower total project costs when compared to operating a mechanical system over a similar time. The MIARNG decided to conduct a PlumeStop pilot test to determine if this treatment would meet their site goals prior to a possible full-scale application. The goals for this pilot project were to utilize an approach that could both protect the Grayling community from exposure and cost-effectively expand to a full-scale application.

This case study features the following:

  • New, innovative approach using an in situ colloidal activated carbon barrier to eliminate PFAS exposure pathway and protect the community
  • Collaborative effort amongst various State of Michigan and military departments
  • Economical and effective pilot study design