LOGO. Environmental Remediation Technologies Assistant Prof. Tunlawit Satapanajaru,, Ph.D.

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1 LOGO Environmental Remediation Technologies Assistant Prof. Tunlawit Satapanajaru,, Ph.D.

2 Nyer and Morello (1993): proposed different definitions for HZW treatment and HZW remediation HZW treatment: the application of a technology to a specific medium (e.g. water, soil or air) to remove contaminants by such processess as partitioning or destruction. HZW remediation HZW remediation: Cleaning the environment or an entire environment system such as, a wetland or an area surrounding an abandoned chemical plant.

3 Another Difference: HZW treatment : ranges of media are involved. For example: Waste water treatment, most contaminants are treated in water soluble. HZW remediation HZW remediation: Variety of media is involved. For example: aqueous phase, nonaqueous phase, etc.

4 Technology Focus: Air Sparging Bioreactor Landfills Bioremediation of Chlorinated Solvents Bioventing/Biosparging Electrokinetics: Electric Current Technologies Fracturing Ground-Water Circulating Wells In Situ Flushing In Situ Oxidation Multi-Phase Extraction Natural Attenuation Permeable Reactive Barriers Phytoremediation Remediation Optimization Soil Vapor Extraction Soil Washing Solvent Extraction Thermal Desorption

5 Ex-Situ and In- Situ In-Situ Situ: In place does not involve excavating the contaminated materials, or pumping groundwater from the subsurface to the surface, but, instead keeping them in their natural place for treatment. Ex-Situ Situ: involves taking the contaminated media out of its natural place, treating it, and then placing it back from where it came or putting it somewhere else.

6 Mobile Soil Remediation System Designed To Treat Soil Contaminated With Jet Fuel, Gasoline, Diesel Fuel, Heavy Oils And Similar Non-chlorinated Hydrocarbons. System Consists Of (1) 8' Grizzly Feed Unit, (1) Inclined Feed Conveyor, (1) Vibrating Screen With Scale And Inclined Feed Conveyor, (1) Rotary Kiln Approximate Deg C Temp Range, (1) Discharge Conveyor, (1) Pulse Jet Bag Collector And (1) Afterburner. Approximate Efficiency Of 99.8% For Coil Containing 2,000 Ppm Total Petroleum Hydrocarbons. Mounted On Various Size Trailers.

7 Capping Capping refers to the construction of an impermeable barrier that would limit human and ecological risks associated with the subsurface contamination Engineered Cover

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9 Revegetated clay capping over waste rock at Mt Lyell Mine - part of the remediation program managed jointly by the Commonwealth through the Supervising Scientist, and the Tasmanian Department of Environment and Land Management.

10 Capping is one of the most common forms of remediation due to it 1. Inexpensiveness and 2. ability to limit the movement of gases from the subsurface to the air, to prevent the intrusion of water, plants and small animals into the contaminated media.

11 Disadvantages of Capping This remediation method does not destroy the compound, lessen toxicity, reduce inherent mobility or volume of the hazardous contaminants, but it does limit its migration Vegetation can destroy a cap over time, hence maintenance of the cap for long periods of time is necessary if the contaminant does not undergo degradation

12 Soil Vapor Extraction (SVE) Soil vapor extraction (SVE), also known as "soil venting" or "vacuum extraction", is an in situ remedial technology that reduces concentrations of volatile constituents in petroleum products adsorbed to soils in the unsaturated (vadose) zone. In this technology, a vacuum is applied through wells near the source of contamination in the soil. Volatile constituents of the contaminant mass "evaporate" and the vapors are drawn toward the extraction wells. Extracted vapor is then treated as necessary (commonly with carbon adsorption) before being released to the atmosphere.

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14 List of contaminants that can be cleaned up using SVE Volatiles Semivolatiles Hydrocarbon Benzene Toluene Xylene Ethylbenzene Hexane Chloroform Methylene chloride PCE (Tetrachloroethylene) TCE and DCE TCA (Trichloroethane) MEK (methyl ethyl ketone) Chlorobenzene Dichlorobenzene (DCB) Trichloropropane Gasoline Jet fuel Diesel Kerosene Heavy Naphthas

15 Some of the factors that determine the effectiveness of SVE are: -permeability of the soil, -soil structure, -soil moisture, and -depth to groundwater.

16 Permeability of the soil, The permeability of the soil affects the rate of air and vapor movement through the soil; the higher the permeability of the soil, the faster the movement and (ideally) the greater the amount of vapors that can be extracted.

17 Soil Structure Soil structure is important to SVE effectiveness because they can TEXT affect how TEXT and where TEXT soil vapors TEXT will flow within the soil matrix under extraction conditions. Structural characteristics (e.g., layering, fractures) can result in preferential flow behavior that can lead to ineffective or significantly extended remedial times if they are positioned so that the induced air flow occurs outside the area of contamination.

18 Soil Structure and Air Flow Single Grain Granular Blocky Rapid Rapid-Moderate Moderate-Slow Prismatic Platy Massive Moderate-Slow Slow-Very Slow Very Slow

19 Soil Moisture Content High moisture content in soils can reduce soil permeability and, consequently, the effectiveness of SVE by restricting the flow of air through soil pores. Fine-grained soils create a thicker capillary fringe than coarse-grained soils.

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21 AHA conducted large-scale pilot testing of SVE/AS

22 Storage tanks for Special Antarctic Blend diesel, a spill site at Macquarie Island. SVE

23 The Electrokinetic Remediation (ER) The Electrokinetic Remediation (ER) process removes metals and organic contaminants from low permeability soil, mud, sludge, and marine dredging. ER uses electrochemical and electrokinetic processes to desorb, and then remove, metals and polar organics. This in situ soil processing technology is primarily a separation and removal technique for extracting contaminants from soils.

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26 Installing electrodes at Paducah, KY, USA

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29 Hot Water or Steam Flushing/Stripping Steam is forced into an aquifer through injection wells to vaporize volatile and semivolatile contaminants. Vaporized components rise to the unsaturated zone where they are removed by vacuum extraction and then treated.

30 Hot water or steam-based techniques include 1.Contained Recovery of Oily Waste (CROW ), 2.Steam Injection and Vacuum Extraction (SIVE ), 3.In Situ Steam-Enhanced Extraction (ISEE ), and 4. Steam-Enhanced Recovery Process (SERP ).

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32 Applicability: The target contaminant groups for hot water or steam flushing/stripping are VOCs and fuels. VOCs also can be treated by this technology, but there are more costeffective processes for sites contaminated with VOCs. This technology can be applied at manufactured gas plants, wood-treating sites, petroleum-refining facilities, and other sites with soils containing light to dense organic liquids, such as coal tars, pentachlorophenol solutions, creosote, and petroleum by-products.

33 Limitations Large subsurface objects can cause access/operating difficulties Soil that is very impermeable or that has a high moisture content can decrease the efficiency of these systems Process requires more skill and operator expertise often increasing overall cost Soil type, contaminant characteristics and concentrations, geology, gy, and hydrogeology which will significantly impact process effectiveness.

34 Soil Washing: Ex-situ

35 Metolachlor spill site in SW Nebraska Accidental leak filled pesticide runoff lagoon

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39 Rotating Drum Inside Mixer

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41 Pure Product Observed in Some Areas

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44 Microenfractionator Water Tank

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46 Extractable Metolachlor Concentrations (mg/kg) Following Treatment with Zerovalent Iron (Nebraska) Treatments Initial 1 d 14 d 28 d 90 d Mixed Control (Moist) 1,813 1,976 1,766 1,638 1,522 Iron 1, Iron + 1, Acetic Acid Iron + 1, Al 2 (SO 4 ) 3 Iron + AA + Al 2 (SO 4 ) 3 1,

47 What Other Pesticides can be Treated will Zerovalent Iron? Pesticide Initial 90 d % (mg/kg) (mg/kg) Reduction Metolachlor 1, Alachlor Chlorpyrifos Pendimethalin Terbutryn Cyanazine Atrazine Butylate 5 6 N/A Values represent concentrations determined from Fe 0 + Al 2 (SO 4 ) 3 + acetic acid treatment. GC analysis

48 The Rest of the Story

49 The Rest of the Story BEFORE AFTER

50 How Much Does the Iron Treatment Cost? Fe 0 $0.285 per lb $33.63 per yd 3 Al 2 (SO 4 ) 3 $0.17 per lb $8.01 per yd 3 Total $41.64 per yd 3 Must add additional cost for mixing and labor Compare Iron treatment to: Incineration $604 per yd 3 Landspreading $30 per yd 3

51 LOGO