Presentation on theme: "How microbes are used to clean up DOD Installations"— Presentation transcript:
1 How microbes are used to clean up DOD Installations May 10, 2012Bioremediation -How microbes are used to clean up DOD InstallationsTraditional Environmental ServicesInnovative Solutions & TechnologiesChemical • Petroleum • Pharmaceutical • Manufacturing • Utilities • Land Development
2 Overview Who is Solutions-IES? Brief History of Remediation Technology Bioremediation basicsEnhanced Reductive DechlorinationProject ExamplesNew Technologies & Emerging Contaminants
3 Who is Solutions-IES, Inc.? Full service environmental companyFormed in Raleigh in 1999Licensed Engineering and Geology firmWoman Owned Small Business (WOSB)Certified 8(a) DB firmNorth Carolina HUBDCAA approved accounting systemServing DoD and private industryProviding both traditional and innovative solutions
4 Historical Perspective Pump & TreatDig & HaulEnergy & Capital intensiveTransfer contamination between mediumDifficult to reach closure
5 Historical Perspective (mid-1990s to mid-2000s)In Situ Treatment TechnologiesPhysical:Air Sparge;Soil Vacuum Extraction (SVE);In Situ Chemical Oxidation (ISCO);Fe0 wallsBiological:Biosparge;Biovent;Oxygen and Nutrient Addition;Substrate Addition;Biobarriers
6 Current Perspective (mid-2000s to now) Optimization Sustainability Emerging ContaminantsChlordane1,4-DioxanePFOS/PFOALow Permeability Zones
8 In Situ Bioremediation In PlaceBioMicrobialRemediationMethod to FixBiological agents (bacteria, fungi, plants, or their enzymes) used to clean up pollution in the environment.Reference: Lisa Alvarez-Cohen, Civil and Environmental EngineeringUniversity of California, Berkeley, Earth Science Division, LBNL
9 (something to breathe) How Does It Work?Growth-Promoting Biological ReductionMicrobesMicrobeHow about sulfate reduction and how does the sulfate work.Microorganisms need food (like PHc) and an electron acceptor (in the way we use oxygen) to reproduce and acquire energyConveniently for us, during this life cycle – the microorganism can degrade the PHCs to produce waste products and energyIn the case where the aquifer system is anaerobic, as we have shown that many are, the microrganisms need a supply of other electron acceptors like sulfate to grow and reproduce – AND degrade PHC+++Electron Donor(Food)Electron Acceptor(something to breathe)[O2, NO3-, SO42-, TCE, etc.]Waste Products[CO2, N2, FeS2, Cl-]Energy(Drawing Modified from AFCEE and Wiedemeier)
10 Applying In Situ Bioremediation Natural AttenuationHave MicrobesHave food and nutrientsBiostimulationNeed food or nutrientsBioaugmentationNeed MicrobesNatural Attenuation – biotransformation occurs naturally: indigenous microbes present, substrates & nutrients present (can be MNA)Biostimulation - indigenous microbes present, substrates &/or nutrients must be addedBioaugmentation – indigenous microbes not present, organisms are added
13 Enhanced Reductive Dechlorination In Situ anaerobic bioremediationInjected into contaminated aquiferSource zone and/or PRB treatmentThe organic substrate:Develops an anaerobic and reducing treatment zoneGenerates hydrogen through fermentation reactionsStimulates microbial growth and metabolism of contaminants of concern
14 Dehalococcoides ethenogenes Multiple strains (BAV1, 195, VS, MB, FL2)Obligate anaerobeDisc-shaped; spontaneous motilityPrefers neutral pH environmentComplete dechlorination to VC & etheneGrows slowly; prefers life in consortiumUses acetate for C source;H2 as electron donorCan use chloroethenes,chlorophenols and PCBs asterminal electron acceptors.
15 AEC Tarheel Army Missile Plant Burlington, NC In Situ Bioremediation of TCE
16 Tarheel Army Missile Plant 1944 – 1992 GOCO Facility1993 Soil and groundwater contamination discovered (BTEX and TCE)1995 AS/SVE placed in operation1999 P&T initiated NW corner2003 Guaranteed fixed price bids from multiple vendors2004 Army selects Solutions-IES to perform work2004 AS/SVE system turned off and Solutions-IES begins EOS® injection
17 Costs (in $1,000) Vendor Process - Reagent Pilot (GFP) Full (Est.) TotalNAMNA250Solutions-IESERD - EOS256728984Magnus pHACometabolic- C3H83218941,215Cl-SolutionsCometabolic- Cl-Out3731,1411,515ArcadisERD - molasses3391,4561,795Electro-PetroleumAS with CO22911,7632,054RegenesisERD - HRC4751,6452,120Geo-CleanseISCO - Fenton2812,4112,692
18 TAMP Site Conditions Source area 100’ x 100’ Existing AS/SVE System Oxidative conditionsChlorinated Solvents2 – 4 mg/L
19 Regulatory Challenges Groundwater ReinjectionRecovered groundwater is a “waste”Innovative below-ground reinjection systemBioaugmentationFirst approved use of DHCbioaugmentation in NC
20 TAMP - Summary EOS® effectively distributed throughout treatment area Quickly established favorable geochemistry for reductive dechlorinationTCE reduced to below detection (<1.0 µg/L) in monitor wells in treatment areaRemedial goals met within6 months of injectionUS Army has sold property!Site has been redeveloped ascommercial / office complex
21 NAVFAC Southeast NAS Pensacola SWMU 1 – WWTP In Situ Bioremediation of TCE in a Sulfate-Rich Acidic Aquifer
22 Site History Former WWTP (SWMU 1), TCE plume with DNAPL source Sulfuric acid spill 1983Concentrations in the source area:pH – 3.5TCE – 18,000 µg/LRemedial activities:P&TISCO w/Fenton’sMNA for downgradient plumeFurther treatment requiredThe WWTP received domestic and industrial wastes from the 40’s through the 70’s. Releases resulted in xxxx. NAVFAC has tried several remedial actions to address the contamination including pump and treat and isco using Fenton’s reagent. The combination of DNAPL and very low pH levels resulting from the sulfuric acid spill would imply that biological reductive dechlorination may be limited or impossible. Our objective was to evaluate the potential for a substrate with added buffering agents to raise the pH levels and promote biological reductive dechlorination.
23 Remediation Plan AquaBupH™ to promote in situ bioremediation Emulsified oil substrateAlkaline solids to adjust pHNutrientsPilot Study – 20082 injections in source areaFull-Scale – 20102 rounds of injectionsRemedial objectives: raise pH and distribute oil to promote biodegradation. This project has progressed in a series of stages. We began work in 2008 with a small pilot study in the presumed source area where injected an emulsified oil substrate (EOS) with alkaline solids – AquaBupH. We saw a very good response in the well with the highest concentrations (AE-01), pH levels were adjusted and concentrations diminished. Based on those results, NAVFAC contracted us to conduct a full-scale injection. We collected some additional information on the aquifer materials and geochemistry which I will discuss in more detail later. In May/June 2010, we injected AquaBupH across the site.AquaBupH™ is a licensed product of EOS Remediation, LLC.; Raleigh, NC
24 pH affects on Dehalococcoides sp. Ashley Eaddy, Scale-Up and Characterization of an Enrichment Culture for Bioaugmentation of the P-Area Chlorinated Ethene Plume at the Savannah River Site. M.S. Thesis, Clemson University.
25 Total Organic Carbon & pH Results TOC Concentration (mg/L)pHTOC distributed well across the site. pH levels raised in many of the wells, some lag in other wells presumably as buffer overcomes the high acidity of the aquifer. pH levels in the wells exposed to pilot study have responded well and pH is within the optimal range for bioreductive dechlorination. In addition, we had strongly reducing ORP values, we were generating methane and the aquifer conditions appeared to be appropriate for the microbes to do their work.
28 Science, Technology & Planning Received Approval for New Pilot TestPrecipitate excess sulfideUnlock microbial toxicityAllow increased growth of DHCEnhance reductive dechlorination even further than already observed
29 Emerging Contaminants & New TechnologiesSoil RemediationVOS™Range SustainabilityChlordaneGW RemediationEAS™MNA for perchlorate remediation
30 Summary Bioremediation On-going Research Wide range of applicability One of many remediation optionsSustainableCost-effectiveOn-going ResearchMicro-Biological Tools (MBTs)Emerging ContaminantsOptimization
31 Contact Tony Lieberman Solutions-IES, Inc. Raleigh, NC (ext. 117)