U S I N G L I Q U I D A C T I V AT E D C A R B O N F O R S U C C E S S F U L B I O D E G R A D AT I O N C a s e S t u d y U s i n g P l u m e S t o p ® L i q u i d A c t i v a t e d C a r b o n ™

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This case study reviews a challenging site encompassing approximately 60 acres in rural South Carolina where a remedial facility assessment (RFA) identified 44 solid waste management units (SWMUs) and three areas of concern (AOCs). The overall project effort spanned some 20 years. The recent remedial objective focused on reducing contaminant concentrations within the downgradient plume and limiting further migration.

A pilot test was followed by a full-scale implementation and resulted in contaminant reductions ranging from 98% to 100% within the zone of influence. Details of the remedial design approach are provided along with verified remedial outcomes.

O V E R V I E W

PlumeStop® was used in both the pilot test and full-scale application to successfully treat the downgradient portion of a long, narrow cVOC plume

Combined remedies implemented with use of a controlled-release electron donor (HRC®) and bioaugmentation culture (BDI® Plus) to enhance reductive dechlorination

Preliminary performance monitoring results of the full-scale implementation indicate contaminant concentration reductions of 98-100% for wells located within the zone of influence

Indicator parameters are showing positive results, indicating the degradation process is ongoing and progressing.

A one-year performance monitoring event will take place in January 2017 and will allow for evaluation of remedial progress at additional monitoring wells located further downgradient of the injection barriers

Based on the success of the pilot tests, PlumeStop was used in full-scale implementation utilizing an injection barrier design with three, 400-foot long barriers

P R O J E C T H I G H L I G H T S

9 8 - 1 0 0 %R E D U C T I O N

O N E Y E A RM O N I T O R I N G

D E G R A D A T I O N O N G O I N G A N DP R O G R E S S I N G

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Former manufacturing facility began operations

RFI report approved by agencies

Several rounds of source area treatment completed

Nanoscale ZVI pilot tests and injections

RCRA Consent Order issued

Remedial Design completed

Remedial Objective: reduce contaminant

concentrations within the downgradient plume and

limit further migration

RCRA Facility Assessment was completed, RFA identified

44 Solid Waste Management Units (SWMUs) and three Areas of Concern (AOCs)

PlumeStop / HRC / BDI Plus injections in the source area

Remedial alternatives evaluation completed for downgradient area

RFI completed and report submitted

Late 2015-2016 Full-scale implementation of the downgradient remedy

Site goals achieved with 98-100% reductions within three months of application

B A C K G R O U N D A N D T I M E L I N E

1952

2010

1989

2014

2007

2016

1998

2015

A former industrial site in rural South Carolina showed high levels of cVOC contamination in the soil and groundwater. The site, which started as a manufacturing facility in the 1950s, included stratigraphy consisting of coastal plain sediments composed of clay, silt, and sand units. The target unit consisted of a sandy clay with sand stringers. Ongoing Concern with Remedial Efforts Included Nanoscale Zero Valeant Iron (ZVI) Among Other SolutionsRemediation efforts using ZVI did not adequately address the contaminant levels required and the environmental firm, Woodard and Curran®, looked at alternative solutions that would successfully meet site goals. Woodard and Curran conducted a Remedial Alternatives Evaluation (REA) for the downgradient portion of the plume and recommended accelerated biodegradation using PlumeStop® Liquid Activated CarbonTM (LAC).

Pilot Test Using PlumeStop Leads to Full-Scale ImplementationA pilot test was conducted, including injection of PlumeStop with a controlled-release electron donor (HRC®) and bioaugmentation culture (BDI® Plus) to enhance reductive dechlorination. The pilot study results demonstrated total cVOCs decreased between 98.7 and 100 percent in the two pilot test areas. Based on pilot test results, a full-scale remedial design and implementation using injection barriers was completed in 2016. Performance monitoring of the site is ongoing with a one-year performance monitoring event scheduled for 2017.

A B O U T T H E P R O J E C T

Site Details

Site Type: Industrial

Contaminant of Concern: cVOCs

Remediation Approach: In situ Sorption and Biodegradation

Technology Used:

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W H Y P L U M E S T O P ® ?

Having considered a number of remediation treatment options prior to PlumeStop®, Woodard and Curran wanted a solution that would be both cost-effective and efficient. PlumeStop, a Liquid Activated Carbon™ technology, promised both. The benefit to PlumeStop’s dispersive properties is its ability to sorb contaminants, quickly removing them from the mobile phase while providing a high surface area matrix which proves favorable for microbial colonization and growth. This is especially important when it comes to low contaminant concentrations as was the case at this site, where prior efforts to remediate addressed some but not all of the contaminant levels present. There was also concern of the plume spreading beyond the area of concern and toward a residential area. With the success of the full-scale application treating the downgradient portion of the long narrow plume, Woodard and Curran is now working with REGENESIS to apply PlumeStop into additional hydrostratigraphic units at greater depths where cVOC contaminants are present.

What is PlumeStop?PlumeStop Liquid Activated Carbon is composed of very fine particles of activated carbon (1-2µm) suspended in water through the use of a unique organic polymer dispersion chemistry.

Once in the subsurface, the material behaves as a colloidal biomatrix binding to the aquifer matrix, rapidly removing contaminants from groundwater, and expediting permanent contaminant biodegradation.

Specifically, PlumeStop:• Rapidly reduces dissolved-phase plumes in

days/weeks• Distributes widely under low injection pressures• Provides a colloidal biomatrix that completely

biodegrades contaminants in-place• Stops contaminant migration and protects

sensitive receptors• Provides a long-term means of addressing matrix

back–diffusion• Eliminates excessive time and end-point

uncertainty associated with groundwater remediation

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PILOT TEST OVERVIEW

D E S I G N E F F O R T SPRE-REMEDIALAs part of their pre-remedial design efforts, Woodard and Curran prepared a work plan that was submitted and approved by the USEPA and the South Carolina Department of Health & Environmental Control (SCDHEC).

In addition, five delineation boring transects were completed. Woodard and Curran and REGENESIS collected both soil and groundwater samples for field analysis to help delineate plume width.

Results of the pre-remedial design were used to:

• Locate additional monitoring wells (to be used for performance monitoring)

• Update the conceptual site model (plume width and length)

• Serve as the basis for recommending the initial pilot study

Pilot Test Results

BL-55-II Pilot Test Summary• Injection Points = 10• PlumeStop Injected = 1880 gallons• Controlled Electron Donor (HRC) Injected = 300 pounds• Biological Amendment (BDI+) Injected = 9 liters

BL-59-II Pilot TestSummary• Injection Points = 12• PlumeStop Injected = 1940 gallons• Controlled Electron Donor (HRC) Injected = 300 pounds• Biological Amendment (BDI+) Injected = 9 liters

BL-55-II Time Trend Graph

BL-59-II Time Trend Graph

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REGENESIS provided a suggested site/injection design with details of the proposed remedial action that included dosage, product volume and injection point spacing as shown in figure.

Remedial Action Plan

Remedial Design

Preliminary Performance Monitoring Results

The design included three injection barriers each 400 feet long - that transected the plume at varying distances from the source area.

Woodard and Curran worked with REGENESIS to determine optimum injection point spacing, dosage, and product volumes, while working with off-site landowners regarding access issues.

PERFORMANCE MONITORING

Performance monitoring has taken place at three and six months, post-injection. A one year event is scheduled for January 2017.

FULL-SCALE DESIGN

REMEDIAL DESIGN

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FULL-SCALE DESIGN

REMEDIAL DESIGN

P R O J E C T S U M M A R Y

Pilot Test Application Indicated Rapid and Sustained DegradationThe successful pilot study application of PlumeStop, HRC and BDI Plus gave Woodard and Curran the confidence to propose this approach to their client as a full-scale application. The pilot test results indicated a rapid and sustained degradation of cVOCs in groundwater which led Woodard and Curran to believe that these results could be duplicated in the proposed full-scale application.

PlumeStop Used in Full-Scale ImplementationBased on the success of the pilot tests, PlumeStop was also used in full-scale implementation utilizing an injection barrier design with three, 400-foot long barriers. The full-scale application successfully treated the downgradient portion of a long, narrow cVOC plume with post-injection performance monitoring of the pilot test resulting in 90 to 100 percent reduction in cVOC concentrations.

Preliminary performance monitoring results of the full-scale implementation indicate contaminant concentration reductions of 98 to 100 percent for wells located within the zone of influence. Indicator parameters are showing positive results indicating the degradation process is ongoing. A one-year performance monitoring event is scheduled for 2017, and will allow for evaluation of remedial progress at additional monitoring wells located further downgradient of the injection barriers.

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I N T E R E S T E D I N R E M E D I A T I O N S O L U T I O N S F O R Y O U R S I T E ?

REGENESIS provides a range of specialized remediation which include treatment technology selection, application design, on-site services, data interpretation and performance reviews.

We partner with environmental consultants and engineers who engage us for one of several reasons:

• To achieve successful site closure efficiently and cost-effectively• To evaluate a range of sites impacted with subsurface contamination• To minimize risk and increase the certainty of remediation with turn-key, results-based solutions and services• To help navigate complex regulatory frameworks and provide end user information• To review site remediation performance and results, ensuring timely and successful treatment outcomes

With visibility on 1,000’s of projects annually, REGENESIS has exposure to a wide spectrum of sites. Our Technical Solutions Managers will provide you with a customized remediation solution designed to achieve your goals.

TO GET CONNECTED WITH A TECHNICAL SOLUTIONS MANAGER, PLEASE CALL 949.366.8000

OR VISIT WWW.REGENESIS.COM