Posts

California Site Closure with Petrox Bioremediation

/in , , , , /by

Southern California Gasoline UST Release Site

After removal of USTs, piping and surrounding soils, ground water was treated with 110 gallons of Petrox® by direct injection in December 2009.  Post-treatment sampling shows that the bioaugmentation reduced the contaminant levels to below regulatory standards by the next semi-annual sampling round.

Sampling Date

 TPHg Benzene Toluene Ethylbenzene

Total   Xylenes

 MTBE
Pre-bioaugmentation

10/6/09

 1,200 320 7.2 700

70

 5
Post-bioaugmentation

4/26/10

 <50 <0.5 <0.51 <1

<5

 <0.5

All concentrations shown in µg/L.

Florida Site Closures With One Petrox Application

/in , , , , /by

The following applications demonstrate the significant results that can be achieved with a single application of Petrox bioremediation.

Florida Panhandle Gas Station

Facility ID # 32-8520334

Petrox was injected through horizontal drilling to address a ground water plume with limited surface access.  After a single Petrox® application there was significant reduction in the contaminant concentrations.

Sampling Date Benzene Toluene Ethyl benzene Xylene Naph-thalene 2-Methyl naphthalene
Pre- bioaugmentation 11/11/05 4,300 3,000 1,300 5,300 240 48
10/23/07 2,700 4,200 860 5,700 240 41
Post-bioaugmentation 11/06/08 1.7 8.5 0.71 5.1 0.49 0.45
1/22/09 0.88 0.64 0.43 1.3 0.49 0.45

All Concentrations shown in µg/L.

 

Southeast Florida Gas Station

Facility ID 8838788

After removal of USTs, piping and surrounding soils Ground water was treated with 110 gallons of Petrox® by direct injection in June 2009.  Sampling six months after the Petrox® treatment showed significant reductions in all contaminants.

Sampling Date Benzene Toluene Ethylbenzene Total Xylenes
Pre-  bioaugmentation 4/4/2008 480 1800.0 110.0 900.0
Post- bioaugmentation 11/12/09 <0.5 <0.51 <0.44 <0.5

All concentrations shown in µg/L.

 

Southeastern Florida Marina

Tequesta, Florida

Facility ID # 43-8731703

Subsequent to the removal of petroleum underground storage tanks (USTs), piping and surrounding soils for redevelopment, residual soil and ground water contamination at the site were treated with Petrox® bioremediation.  Petrox® was applied to the soil that was removed during the UST removals and to the ground water in the UST cavity.

Approximately 4,000 tons of soil were removed from the excavation and stockpiled on site for treatment.  The total BTEX concentrations in the excavated soil were up to 100 mg/kg.  Petrox® bioremediation was applied to the stockpiled soils.  In less than 90 days the petroleum was no longer detected in the soil and in the soil met the applicable Florida DEP standards.

Petrox® bioremediation was applied to the water in the former UST cavity to treat residual petroleum.  The proximity of the cavity to the Jupiter Sound indicated that the ground water was strongly influenced by infiltration from the Sound.  After less than 90 days post treatment, the water in the excavation also met the applicable Florida DEP standards.

 

Maximum Water Conc. Benzene Toluene Ethylbenzene Total Xylenes
Pre-treatment 1,960 5,140 1,860 18,340
90 days after treatment 3.7 BDL BDL BDL

All concentrations shown in µg/L. BDL= below detection limits.

 

Central Florida Gas Station

Petrox was applied to the ground water in an area around a single monitoring well that did not respond to another treatment as well as the rest of the plume.  A single 10-gallon application of Petrox® was sufficient to apply for site closure.

Sampling Date Benzene Toluene Ethylbenzene Total Xylenes
Pre- treatment 8/2/2007 11,100 1,250 1,260 5,040
Post-treatment 10/4/07 1,600 20.0 290. 840.
11/19/07 0.40 1.0 1.00 32.0

All concentrations shown in µg/L.

 

Bioremediation of BTEX at an Industrial Site in Florida

/in , , , , /by

Background

Petrox® bioaugmentation was used to remediate ground water contaminated by benzene, toluene, ethylbenzene and xylene (BTEX) at an industrial facility in central Florida (Facility ID No. 8521705). The bioremediation was implemented in perimeter wells around the source area where air sparging and vapor extraction was implemented. This combined approach provided cost-effective, full-site remediation by using complementary technologies.

Remediation Approach and Results

Petrox® was introduced into the contaminated ground water in the perimeter of the source area plume by injection through temporary well points. Two applications of Petrox® were completed. The initial application was in December 2007 and a subsequent application was completed in April 2008. During each application 550 gallons of Petrox® microbial slurry were injected into the ground water through 19 injection points. The treatment covered an area of approximately 7,000 square feet.

The ground water treatment results were monitored by laboratory analysis of ground water samples for the contaminants of concern. The quarterly monitoring results after the applications showed an immediate and continuous decrease in the BTEX concentrations. The following chart shows the total BTEX concentrations in three quarterly sampling events after the implementation of Petrox® bioaugmentation.

industrial-site6

Conclusions

This project demonstrates two of the benefits of aerobic bioaugmentation. Petrox® organisms were able to metabolize the BTEX compounds, which were initially at part per million levels, to below detection limits. Bioaugmentation provides active control of the site with hydrocarbon-degrading organisms compatible with air sparging and vapor extraction in the source area, where the contaminant concentrations persisted longer than in the bioaugmentation area.

Petrox® Bioaugmentation in Bedrock

/in , , , , , /by

Case Study: Petroleum Remediation in Central New Jersey

Summary

Petrox® bioaugmentation was implemented at a petroleum remediation site in Morris County, New Jersey to destroy residual petroleum compounds in ground water. The impacted ground water was in bedrock fractures under and down gradient of a former UST location. The UST was removed and an oxygen release compound was added to the ground water to stimulate bioremediation. However, residual contamination persisted and Petrox® bioremediation was implemented to remove the residual low concentration found at the site.

Geology and Hydrogeology

The bedrock surface was fairly close to the ground surface and the first ground water encountered upon drilling at the site was within the bedrock. Impacted ground water was contained within the fractures near the bedrock surface in a zone estimated to be 40 feet thick.

Contamination

Low concentrations of benzene, xylene, ethylbenzene and toluene were present in ground water at and down gradient of the former UST cavity. The area of proposed treatment was 3,600 square feet.

Implementation

Petrox was applied in two monthly applications of 8 units each. One unit of Petrox® is a 55-gallon slurry with a microbial concentration of 109 cfu/ml. ORC socks were installed in treatment wells to provide an oxygen source for the petroleum metabolism.

The monthly Petrox® injections were on May 29, 2009 and June 26, 2009. Post -treatment samples were taken on June 10, 2009 and May 4, 2010. The following table shows the contaminant concentration treads in the treatment area.

case-study-6-table

Results

The treatment was successful in reducing the BTEX concentration at the site. However, the increase in concentrations after the first treatment showed that there were residual petroleum constituents in the source that was not reflected in the pre-treatment sampling. Petrox® microbes were detected in all of the bedrock sampling points as far as 30 feet down gradient of an injection point. Overall the treatment verified the effectiveness of Petrox® bioaugmentation in fractured bedrock.