Americas
Europe
Français
Deutsch
Italiano
Español
Enhanced Recovery & Biodegradation of Petroleum Hydrocarbons – Sweden
Summary
A site investigation undertaken by a remediation contractor in Växjö, Sweden, identified up to 1.4 m of LNAPL on top of the groundwater beneath an industrial unit. The source of the contamination was a boiler in the basement of the facility. It was determined that the contamination posed a vapour risk to the site users. The proposed strategy was therefore to remove the LNAPL, reduce the adsorbed mass and treat the dissolved phase contamination to low levels. This was to be completed within the building, it’s basement and the car park downgradient.
Treatment
In order to efficiently address both the free and dissolved phase petroleum hydrocarbon contamination an integrated in-situ remediation strategy was adopted. A Multi-Phase Extraction (MPE) system was installed across the target area. This was used firstly to extract the easily removable LNAPL observed at the site. Following this, several round of PetroCleanze® were applied into the subsurface to cause the temporary desorption of the soil contamination within the smear zone. The MPE system was then used to remove this ‘rebound’ each time.
Once no further LNAPL was observed after the PetroCleanze application, ORC Advanced® was applied to enhance the biological degradation of the residual dissolved phase contamination to reach the target values.
What’s Special
- An integrated in situ remediation method allowed for treatment of LNAPL down to low dissolved phase contamination under an industrial unit, avoiding any demolition or excavation.
- PetroCleanze enhanced the performance of the MPE in order to reduce the asymptote achieved and avoid rebound from residual sorbed contamination.
- Augmentation of the MPE reduced time onsite and the cost of the remediation programme.
- ORC Advanced was used once only dissolved phase contamination was observed, maintaining the efficiency of the remedial programme and successfully achieving stringent target values.
PlumeStop® and ORC Advanced® Treat BTEX to Non-Detect in 1 Month
Project Highlights
- Benzene (BTEX) and TPH-d (diesel) were reduced to non-detect within one month with no rebound
- Pre-project verification testing provided hydrogeological data to optimize the successful application of PlumeStop and ORC Advanced
- Active site did not impede remediation efforts
Project Summary
An active gas station in the Pacific Northwest was impacted with BTEX concentrations from a petroleum release. Following remediation of the source, residual BTEX concentrations persisted in a down gradient well. A new combined remedies in situ program using PlumeStop and ORC Advanced was designed. Following the verification testing, REGENESIS co-applied PlumeStop and ORC Advanced into the residual BTEX plume. After one month, sampling was conducted showing contaminants had been dramatically reduced to non-detect levels.
Remediation Approach
REGENESIS worked closely with the project consultant to complete a multi-step verification process prior to remediation. This procedure included a clear water injection to test aquifer properties and soil borings for detailed characterization of the proposed treatment area. This was followed by a pilot injection of PlumeStop to test distribution. The verification testing found that despite soils at the site being classified as clays and silts, there was a sufficient amount of sand present to allow for good distribution. Injection pressures remained below 5 psi for PlumeStop and below 10 psi for ORC Advanced. Distribution of greater than 12 feet was also observed. The verification process was an integral part of the project, helping to more accurately characterize true hydrogeologic conditions. Technical Engineers were able to take the information obtained from the verification process and optimize the PlumeStop and ORC Advanced design. The co-application of the two technologies quickly sorbed dissolved-phase contaminants and promoted aerobic biodegradation.
REGENESIS Solution Applied
PlumeStop Liquid Activated Carbon™ is composed of very fine particles of activated carbon (1-2μm) suspended in water through the use of 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 enhancing permanent contaminant biodegradation. ORC Advanced is a proprietary formulation of food-grade, calcium oxy-hydroxide that produces a controlled release of molecular oxygen for periods of up to 12 months upon hydration.
Results
Residual BTEX and TPH-d concentrations lingering for years are common for gas station sites and often are the only obstacle to closure. The combined remedies application of PlumeStop and ORC Advanced demonstrates a unique ability to attain non-detect levels in a short time frame with substantial cost savings over other approaches, including natural attenuation.
ISCO Treats High Levels of TCE with Planned Enhanced Bio for TPH Treatment
157,000 lbs. of PersulfOx® Applied to Treat Illinois Manufacturing Facility
Project Highlights
- Remediation mandated after oil sheen observed in river adjacent to manufacturing facility
- In Situ chemical oxidation (ISCO) paired with excavation to remediate site
- Tight treatment deadline met through supply of 51 PersulfOx SuperSacks, containing 2,204 lbs. each, which were delivered within a few days’ notice
- TPH soil plume has been reduced by >90% (from 6,111 cubic yards to 555 cubic yards)
Project Summary
An operating metal fabrication facility, located in Illinois, caused subsurface impacts from the use of cutting oils and degreasing solvents. This resulted in high levels of TPH and TCE in soil and groundwater. The state of Illinois cited the facility for a violation when an oil sheen was observed seeping from the property into an adjacent river. A mechanical oil recovery system was installed and absorbent booms were used to stop oil from reaching the river. ISCO was selected as the remediation approach to treat the contamination below the active facility. The TCE area was treated with PersulfOx via injection wells and a soil mixing application with an excavator.
Remediation Approach
Prior to the start of remediation activities, a change in the primary consultant was made and a new consultant was brought in. The new consultant imposed a tight deadline of several months to complete the full scope of remediation activities. REGENESIS was able to assist with keeping the project on-deadline through the timely delivery of 51 PersulfOx SuperSacks, containing 2,204 lbs. each. The PersulfOx SuperSacks were delivered within a few days’ notice. The consultant installed a series of injection wells within and outside of the building. PersulfOx was injected into these wells during three applications over a three-month period. Additionally, the TCE area was treated with PersulfOx® through a soil mixing application using an excavator. The final step of the remediation plan is to treat the TPH-impacted soils outside the building through excavation and the application of Oxygen Release Compound (ORC®) Advanced Pellets which will supply a long-term oxygen source of oxygen for enhanced bioremediation of the residual TPH. The client is also evaluating the use of PlumeStop to change the FOC value of the soil for a site specific Tier 3 closure level via MNA for an area that had extremely high TPH values >40,000ppm.
Technology Description
PersulfOx is a sodium persulfate-based chemical oxidation technology which destroys both hydrocarbon and chlorinated solvent type contaminants in the subsurface. PersulfOx contains a built-in catalyst which activates the persulfate component and generates contaminant-destroying free radicals without the need for the addition of a separate activator.
ORC Advanced Pellets are a pelletized version of REGENESIS’ widely used ORC Advanced and are designed specifically for direct application into excavations, tank pits and trenches. This pelletized, dry application material minimizes airborne dust while eliminating the need for specialized equipment and spray water required for powder-slurry applications.
Safe and Simple Excavation Application Provides Long-Term Treatment
Summary
During the demolition and redevelopment of a former petrol filling station, an underground storage tank was removed. The tank had been used for the storage of diesel and had leaked into the surrounding soils and groundwater. The impacted soils were excavated and removed to a waste management facility. The groundwater within the excavation was impacted with dissolved phase hydrocarbons and required further treatment.
Regenesis provided the remediation contractor with a remedial design for the application of ORC Advanced Pellets to treat the residual contamination within the groundwater in and around the open excavation.
Treatment
ORC Advanced Pellets were applied into the groundwater, in the base of the excavation. This was completed by placing them in an excavator bucket and spreading evenly across the area. By using the pelletised version of ORC Advanced, there was no need for mixing or application using pumps and the potential for dust creation was minimised.
The pellets take only minutes to apply and yet provide a controlled release of oxygen into the groundwater for a period of 9-12 months from a single application. The ORC Advanced stimulates the growth of an aerobic biomass which accelerates the biological degradation of dissolved phase hydrocarbon contamination.
What’s Special?
- The use of ORC Advanced Pellets meant that the contractor could backfill the excavation and continue the build programme with minimal disruption.
- The remediation then continued in situ with no need for physical plant taking up valuable space or requiring maintenance.
- ORC Advanced Pellets provide an effective long-term treatment of residual dissolved phase contamination though a very easy, safe and rapid application process.
Product Description
ORC Advanced Pellets (ORC-A Pellets) are a pelletised version of REGENESIS’ widely-used ORC Advanced and are designed specifically for direct application into excavations, tank pits and trenches. This pelletised, dry application material minimises airborne dust while eliminating the need for specialised equipment and spray water required for powder-slurry applications. ORC Advanced Pellets are approximately 3-10 mm in size.
High TPH Concentrations Treated Using PersulfOx® and ORC® Advanced
Future Site of Stormwater Retention Ponds Remediated with ISCO, Enhanced Aerobic Biodegradation
Project Highlights
- Initial treatment with aerobic bioremediation effectively removed 60% of site contamination.
- PersulfOx® and ORC® Advanced were used to treat two remaining hot spot areas.
- Site closure is pending additional groundwater monitoring.
- Contamination concentrations must be reduced to meet stringent groundwater quality standards.
Project Summary
This site is a former commercial facility in the Southeast with high TRPH contaminant impacts to soils and groundwater. The property is currently vacant and the state department of transportation plans to create a stormwater retention pond on site. However, contaminant concentrations in groundwater need to be reduced to meet stringent groundwater quality standards before any construction can begin.
The plume was first treated via enhanced aerobic bioremediation with ORC Advanced, which effectively removed over 60% of the dissolved-phase contamination within 18 months. In two hot spot areas, residual contamination in the smear zone continued to cause impacts to groundwater. A follow-up treatment combining in situ chemical oxidation and enhacned aerobic bioremediation was employed. PersulfOx and ORC Advanced were used to bring this site towards closure by effectively treating these two hot spot areas. Initial sampling results 30 days after treatment showed attainment of groundwater quality standards.
Remediation Approach
ORC Advanced was injected over 60 direct-push locations across two plume areas. A year and a half post-application, two remaining hot spot areas with residual capillary fringe contamination had caused continued issues. PersulfOx and ORC Advanced were used to bring this site towards closure by effectively treating these two hot spot areas.
Technology Description
ORC Advanced is a proprietary formulation of food-grade, calcium oxy-hydroxide that produces a controlled-release of molecular oxygen for periods of up to 12 months upon hydration.
PersulfOx is a sodium persulfate-based chemical oxidation technology which destroys both hydrocarbon and chlorinated solvent-type contaminants in the subsurface. PersulfOx contains a built-in catalyst which activates the persulfate component and generates contaminant-destroying free radicals without the need for the addition of a separate activator.
Acetone and Petroleum Hydrocarbons Treated at Active Industrial Facility
Combined ISCO/Bioremediation Treatment Approach Reduces Contamination Levels
Project Highlights
- Acetone concentrations pre-remedation were as high as 54,000 μg/L
- Site access agreement required that existing site operations could not be interrupted for construction
- Site water was not allowed to be used therefore all water had to be trucked in and a separate water permit to access city water from fire hydrants was required
Project Summary
A former industrial facility in northern California operated as a gas manufacturing plant from the early 1900s until it was decommissioned in 2001 and sold. The property is currently leased by a bottled water distribution facility.
At this facility, acetone was used extensively in acetylene manufacturing. The acetone was stored on-site in underground storage tanks (UST) but no evidence of leaking acetone USTs was found.
However, high concentrations of acetone – a pre-remediation maximum of 54,000 micrograms per liter (μg/L) were found in one area of the site. Other dissolved chemicals of concern (COC) include gasoline and gasoline-range petroleum hydrocarbons from former USTs such as benzene, toluene, ethylbenzene and xylenes (BTEX).
The extent of contamination in the early 1990s extended to large portions of the site. A pump and treat system was used on-site in 2005, however contamination persisted. Contamination approximately 12 feet below ground surface was detected within the soil. A remediation plan using both ORC® Advanced and RegenOx® was used to treat the remaining contamination.
The site access agreement for this project required that existing site operations could not be interrupted for construction. In order to minimize disturbance to tenants and work within these constraints, all drilling field work was performed on weekends. Site water was not allowed to be used therefore all water had to be trucked in and a separate water permit to access city water from fire hydrants was required. In addition, multiple drill rigs and support vehicles operated within a small area, increasing logistical and safety concerns.
Remediation Approach
A mixture of 6,500 pounds of RegenOx and 3,000 pounds of ORC Advanced was injected at 45 locations using multiple direct-push drill rigs. The injection points were designed in a grid pattern with a nominal 15-foot spacing between injection points, but more densely placed in the area of highest contaminant concentration. Benzene concentrations in groundwater have stabilized at about 10 μg/L and acetone concentrations have stabilized at about 1,600 μg/L. Post-treatment monitoring results show that all the COCs in the treatment area have consistently remained below health-based cleanup levels since the treatment was applied.
Technology Description
Advanced Formula Oxygen Release Compound (ORC Advanced®) is a proprietary formulation of food-grade, calcium oxy-hydroxide that produces a controlled-release of molecular oxygen for periods of up to 12 months upon hydration.
RegenOx is an advanced chemical oxidation technology that destroys contaminants through powerful, yet controlled chemical reactions and not through biological means. This product maximizes in situ performance while using a solid alkaline oxidant that employs a sodium percarbonate complex with a multi-part catalytic formula.
Open Excavation Treatment at Former NJ Service Station
RegenOx® and ORC® Advanced Pellets Remediate Petroleum Hydrocarbon Contamination
Project Highlights
- Former service station contaminated with BTEX levels measuring 11 ppm in groundwater and soil impacts removed through excavation
- Combined remedy to treat the open excavation with both in situ chemical oxidation and enhanced aerobic bioremediation technologies
- RegenOx and ORC Advanced Pellets technologies are compatible/non-corrosive with underground infrastructure and utilities infrastructure in the subsurface
Project Summary
A former service station in New Jersey was contaminated with high levels of BTEX (measuring 11 ppm in groundwater pre-treatment). Due to significant amounts of contaminated soil mass remaining at the former service station, an excavation was proposed by the environmental consultant. RegenOx and ORC Advanced Pellets were applied to the open excavation to chemically oxidize remaining saturated impacts and to promote enhanced aerobic biodegradation of petroleum hydrocarbons in the dissolved phase. Both of these technologies utilize alkaline chemistry (pH > 8), which is non-corrosive to nearby public utilities and the underground infrastructure at the service station.
Remediation Approach
RegenOx and ORC Advanced were co-applied into an open excavation at the former service station site. The excavation extended approximately four feet into the saturated zone. Because the excavation was limited by physical constraints, RegenOx, a chemical oxidant, was applied to the base of the excavation to oxidize and desorb residual petroleum mass from the soil. ORC Advanced Pellets were co-applied to provide a slow release of oxygen (up to 12 months longevity) that promotes enhanced aerobic biodegradation of petroleum hydrocarbons. In total, 2,000 pounds of RegenOx and 882 pounds of ORC Advanced Pellets were co-applied to the 2,600 square foot excavation area.
Technology Description
The advanced formulation of the Oxygen Release Compound (ORC Advanced) is a proprietary formulation of food-grade, calcium oxy-hydroxide that produces a controlled-release of molecular oxygen for periods of up to 12 months upon hydration. The pelletized form of ORC Advanced were designed to improve safety and handling for excavation applications.
RegenOx is an advanced chemical oxidation technology that destroys contaminants through powerful, yet controlled direct oxidation and free-radical reactions. This product maximizes in situ performance through the use of a solid alkaline oxidant (a sodium percarbonate complex) and a multi-part catalyst. These oxidation reactions do not inhibit natural bacterial populations and are compatible with biological treatment methods.
Combined Remedies Treat BTEX Contamination on Government Property
Ontario, Canada Site Remediated with ORC® Advanced and RegenOx®
Project Highlights
- In Situ Chemical Oxidation (ISCO) and Enhanced Biodegradation used post-excavation to treat residual contamination.
- Extensive site mapping conducted with membrane interface probe (MIP) to detect distinct zones of higher mass contamination.
- 95% reductions seen in dissolved phase petroleum hydrocarbon contamination.
Project Summary
A large public works property in Ontario, Canada was contaminated with TPH. Approximately 5,000 gallons of fuel was released into the subsurface primarily due to fuel theft that had taken place on-site. Due to significant volumes of free-product, an excavation occurred followed by skimming activities from 2005-2010. Through extensive site evaluation, it was determined that there was a need for further mass reduction using ISCO.. RegenOx® ISCO was selected for use in the heavily and moderately impacted areas. Enhanced aerobic biodegradation using ORC® Advanced was selected for use in the dissolved-phase areas downgradient from the source. Overall, 96% reductions were seen in dissolved phase petroleum hydrocarbon concentrations.
Remediation Approach
Membrane interface probe (MIP) data was collected and proved to be integral for the remediation design and implementation. Distinct zones with high mass were present on-site and detected through the probe. RegenOx and ORC Advanced were applied via direct-push injections. Approximately 150,000 pounds of RegenOx and 45,000 pounds of ORC Advanced were applied over several injections. Higher concentrations of RegenOx were applied into the vertical zones of higher contamination to improve overall product performance.
Technology Description
Advanced Formula Oxygen Release Compound is a proprietary formulation of food-grade, calcium oxy-hydroxide that produces a controlled-release of molecular oxygen for periods of up to 12 months upon hydration.
RegenOx is an advanced chemical oxidation technology that destroys contaminants through powerful, yet controlled chemical reactions and not through biological means. This product maximizes in situ performance while using a solid alkaline oxidant that employs a sodium percarbonate complex with a multi-part catalytic formula.
PersulfOx® Treats Gasoline Tanker Truck Spill Site
Pilot Study Moved to Full-Scale Application to Remediated Benzene and TPH-G Contamination
Project Highlights
- Pilot study moves to full-scale application after large contamination concentration decrease resulting from in situ chemical oxidation (ISCO).
- High-volume, direct-injection of PersulfOx® ISCO distributes reagent beneath highway.
- ORC Advanced applied to edge of plume to prevent further migration.
- The average reductions of benzene or TPH-G were 83% and 79% respectively.
Project Summary
A gasoline tanker truck rollover occurred in Ringling, Oklahoma resulting in a benzene and TPH-G contamination. A pilot study using PersulfOx ISCO was conducted with up to 98% contamination reduction observed. Upon successful completion of the pilot study, a full-scale application was approved. A series of full-scale ISCO applications commenced to achieve significant knockdown of benzene and TPH-G concentrations at the site.
Remediation Approach
Full-scale PersulfOx injections were focused along a run-off ditch on the east side of the highway where contamination reached the groundwater during the initial spill and also downgradient on the west side of the highway where contamination had migrated.
The intent of injections on the east side of the highway were designed to address source contamination. These injections were also designed to treat the contamination beneath the highway. PersulfOx migrated through the aquifer under the influence of large direct-push injection volumes and a strong underlying groundwater gradient and natural slope of the lower confining bedrock.
Two PersulfOx injections have been completed approximately one month apart while an application of ORC Advanced also was applied in the distal part of the plume to prevent further spreading of BTEX and TPH.
The average reductions of benzene or TPH-G were 83% and 79% respectively. These are encouraging results and indicate beneficial oxidation and mass reduction of fuel hydrocarbon contamination. Ongoing monitoring will determine if additional applications are needed to reach remedial goals.
Technology Description
Advanced Formula Oxygen Release Compound (ORC Advanced®) is a proprietary formulation of food-grade, calcium oxy-hydroxide that produces a controlled-release of molecular oxygen for periods of up to 12 months upon hydration.
PersulfOx is a sodium persulfate-based chemical oxidation technology which destroys both hydrocarbon and chlorinated solvent-type contaminants in the subsurface. PersulfOx contains a built-in catalyst which activates the persulfate component and generates contaminant-destroying free radicals without the need for the addition of a separate activator.
Sequential Anaerobic and Aerobic Treatment of Chlorinated Solvents Achieves MCLs
Project Highlights
- All target compounds reduced to below Maximum Contaminant Level (MCLs) in onsite wells
- Anaerobic biodegradation using Hydrogen Release Compound (HRC®) treats tetrachloroethylene (PCE) and 1,1 dichloroethene (DCE) to below federal MCLs
- Aerobic biodegradation using ORC Advanced® treats vinyl chloride (VC) and 1,1-DCE to below MCLs
- ORC Advanced provided oxygen for a period of 15 months in the target treatment zone
Project Summary
The site is located in the Coastal Plain of South Carolina and is a former light industrial facility. Baseline concentrations of total chlorinated VOCs – which included PCE, dechlorination daughter products, and 1,1- DCE – were as high as 2,000 μg/L in the near-source groundwater.
Initial groundwater treatment injected 2,400 pounds of HRC at the site using direct push technology. VOC concentrations in the target monitoring wells decreased to below federal MCLs for all contaminants except for VC and 1,1-DCE, which appeared to have stabilized between 10-15 μg/L and 7-30 μg/L, respectively.
In an attempt to meet the MCLs for all contaminants and attain regulatory closure, the treatment approach was shifted to aerobic bioremediation to accelerate degradation of residual VC and 1,1-DCE. This approach was based on evidence that aerobic biodegradation of daughter products such as VC can be much faster than anaerobic processes. The aerobic treatment involved injection of 1,360 pounds of ORC Advanced via direct push technology into 22 temporary points.
Technology Description
ORC Advanced is a proprietary formulation of food-grade, calcium oxy-hydroxide that produces a controlled-release of molecular oxygen to enhance aerobic biodegradation.
HRC is a controlled release, electron donor material that, when hydrated, is specifically designed to produce a controlled release of soluble lactate. The newly available lactic acid is highly efficient for the production of dissolved hydrogen to fuel anaerobic biodegradation processes in soil and groundwater.
Results
After initial groundwater treatment of HRC and following application of ORC Advanced, groundwater monitoring showed reductions in VC to below MCL except for periodic detections between 2-3 μg/L and reductions in 1,1-DCE to below the MCL of 7 μg/L onsite. The VOC concentrations and the dissolved oxygen levels demonstrated that ORC Advanced released oxygen for 15 months in the target treatment zone.
