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Innocuous oil as an additive for reductive reactions involving zero valence iron

Description: Reductive reactions involving zero valence iron appear to hold promise for in situ remediation of sites containing chlorinated hydrocarbon solvents and certain reducible metals and radionuclides. Treatment involves the injection of metallic iron and the creation of low levels of dissolved oxygen in the aqueous phase through oxidation of the metallic iron. The use of a biodegradable immiscible and innocuous organic liquid such as vegetable oil as an additive offers several intriguing possibilities. The oil phase creates a large oil-water interface that is immobile with respect to flow in the aqueous phase. This phase will act as a trap for chlorinated hydrocarbons and could potentially increase the reaction efficiency of reductive dehalogenation of chlorinated hydrocarbons by the metallic iron. When iron particles are suspended in the oil before injection they are preferentially held in the oil phase and tend to accumulate at the oil-water interface. Thus oil injection can serve as a mechanism for creating a stable porous curtain of metallic iron in the vadose to maintain a low oxygen environment which will minimize the consumption of the iron by molecular oxygen.
Date: November 1, 1994
Creator: Cary, J. W. & Cantrell, K. J.
Partner: UNT Libraries Government Documents Department

Initial review of the treatment operations at the Installation Logistics Center, Fort Lewis, Washington

Description: An initial review was conducted of the current treatment operations for remediation of groundwater contaminated with trichloroethene (TCE) at the Fort lewis Logistics Center. Results from this review indicate the two pump-and-treat systems are effectively containing the TCE plume within the upper unconfined aquifer (Vashon Drift). However, mass balance calculations show the existing treatment systems alone will not accomplish the remedial action objective of cleaning up the aquifer to drinking water standards within 30 years as specified in the Record of Decision (ROD). This conclusion is based on the estimated mass of TCE at the source term (51,000 kg), the calculated mass of TCE in the aquifer (4,900 kg), and the removal rate of the pump-and-treat systems that currently ranges from 324 to 667 kg of TCe per year. Four areas within the TCE plume have been identified where enhancements could be made to the existing treatment operations. These are, Area 1 -- the vadose zone source, Area 2 -- the saturated zone source, Area 3 -- a containment area down gradient of Areas 1 and 2, and Area 4 -- the remainder of the plume. This report lists several remedial technologies including new and innovative technologies for these four areas that may help clean up the site to regulatory acceptable levels, shorten the timeframe for cleanup, or significantly reduce currently estimated Installation Restoration program (IRP) life-cycle costs.
Date: July 1, 1998
Creator: Cantrell, K.J.; Liikala, T.L.; Gilmore, T.J. & Last, G.V.
Partner: UNT Libraries Government Documents Department

Subsurface barrier design alternatives for confinement and controlled advection flow

Description: Various technologies and designs are being considered to serve as subsurface barriers to confine or control contaminant migration from underground waste storage or disposal structures containing radioactive and hazardous wastes. Alternatives including direct-coupled flood and controlled advection designs are described as preconceptual examples. Prototype geotechnical equipment for testing and demonstration of these alternative designs tested at the Hanford Geotechnical Development and Test Facility and the Hanford Small-Tube Lysimeter Facility include mobile high-pressure injectors and pumps, mobile transport and pumping units, vibratory and impact pile drivers, and mobile batching systems. Preliminary laboratory testing of barrier materials and additive sequestering agents have been completed and are described.
Date: February 1, 1994
Creator: Phillips, S. J.; Stewart, W. E.; Alexander, R. G.; Cantrell, K. J. & McLaughlin, T. J.
Partner: UNT Libraries Government Documents Department

Performance assessment for the disposal of low-level waste in the 200 West Area Burial Grounds

Description: This document reports the findings of a performance assessment (PA) analysis for the disposal of solid low-level radioactive waste (LLW) in the 200 West Area Low-Level Waste Burial Grounds (LLBG) in the northwest corner of the 200 West Area of the Hanford Site. This PA analysis is required by US Department of Energy (DOE) Order 5820.2A (DOE 1988a) to demonstrate that a given disposal practice is in compliance with a set of performance objectives quantified in the order. These performance objectives are applicable to the disposal of DOE-generated LLW at any DOE-operated site after the finalization of the order in September 1988. At the Hanford Site, DOE, Richland Operations Office (RL) has issued a site-specific supplement to DOE Order 5820.2A, DOE-RL 5820.2A (DOE 1993), which provides additiona I ce objectives that must be satisfied.
Date: June 1, 1995
Creator: Wood, M.I.; Khaleel, R.; Rittmann, P.D.; Lu, A.H.; Finfrock, S.H.; DeLorenzo, T.H. et al.
Partner: UNT Libraries Government Documents Department

Characterization of radionuclide-chelating agent complexes found in low-level radioactive decontamination waste. Literature review

Description: The US Nuclear Regulatory Commission is responsible for regulating the safe land disposal of low-level radioactive wastes that may contain organic chelating agents. Such agents include ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), picolinic acid, oxalic acid, and citric acid, and can form radionuclide-chelate complexes that may enhance the migration of radionuclides from disposal sites. Data from the available literature indicate that chelates can leach from solidified decontamination wastes in moderate concentration (1--100 ppm) and can potentially complex certain radionuclides in the leachates. In general it appears that both EDTA and DTPA have the potential to mobilize radionuclides from waste disposal sites because such chelates can leach in moderate concentration, form strong radionuclide-chelate complexes, and can be recalcitrant to biodegradation. It also appears that oxalic acid and citric acid will not greatly enhance the mobility of radionuclides from waste disposal sites because these chelates do not appear to leach in high concentration, tend to form relatively weak radionuclide-chelate complexes, and can be readily biodegraded. In the case of picolinic acid, insufficient data are available on adsorption, complexation of key radionuclides (such as the actinides), and biodegradation to make definitive predictions, although the available data indicate that picolinic acid can chelate certain radionuclides in the leachates.
Date: March 1, 1996
Creator: Serne, R. J.; Felmy, A. R.; Cantrell, K. J.; Krupka, K. M.; Campbell, J. A.; Bolton, H., Jr. et al.
Partner: UNT Libraries Government Documents Department

Review of potential subsurface permeable barrier emplacement and monitoring technologies

Description: This report focuses on subsurface permeable barrier technologies potentially applicable to existing waste disposal sites. This report describes candidate subsurface permeable barriers, methods for emplacing these barriers, and methods used to monitor the barrier performance. Two types of subsurface barrier systems are described: those that apply to contamination.in the unsaturated zone, and those that apply to groundwater and to mobile contamination near the groundwater table. These barriers may be emplaced either horizontally or vertically depending on waste and site characteristics. Materials for creating permeable subsurface barriers are emplaced using one of three basic methods: injection, in situ mechanical mixing, or excavation-insertion. Injection is the emplacement of dissolved reagents or colloidal suspensions into the soil at elevated pressures. In situ mechanical mixing is the physical blending of the soil and the barrier material underground. Excavation-insertion is the removal of a soil volume and adding barrier materials to the space created. Major vertical barrier emplacement technologies include trenching-backfilling; slurry trenching; and vertical drilling and injection, including boring (earth augering), cable tool drilling, rotary drilling, sonic drilling, jetting methods, injection-mixing in drilled holes, and deep soil mixing. Major horizontal barrier emplacement technologies include horizontal drilling, microtunneling, compaction boring, horizontal emplacement, longwall mining, hydraulic fracturing, and jetting methods.
Date: February 1, 1994
Creator: Riggsbee, W. H.; Treat, R. L.; Stansfield, H. J.; Schwarz, R. M.; Cantrell, K. J. & Phillips, S. J.
Partner: UNT Libraries Government Documents Department

Estimation of the release and migration of lead through soils and groundwater at the Hanford Site 218-E-12B Burial Ground

Description: This report describes the technical basis for a groundwater transport analysis that was conducted to evaluate migration of potentially hazardous materials from the Hanford Site 218-E-12B burial ground. The analysis characterized the geologic, chemical, and hydrologic properties of the disposal site, and used that information to perform a screening analysis for transport of materials from the burial ground to downgradient groundwater locations and to the Columbia River. Subsequent sections of the appendix describe the geologic setting, geochemistry, and hydrology of the disposal site and their relationship to the transport analysis.
Date: October 1, 1992
Creator: Rhoads, K.; Bjornstad, B.N.; Lewis, R.E.; Teel, S.S.; Cantrell, K.J.; Serne, R.J. et al.
Partner: UNT Libraries Government Documents Department

Estimation of the release and migration of lead through soils and groundwater at the Hanford Site 218-E-12B Burial Ground

Description: This study was performed to evaluate the potential for transport of lead from the Hanford Site 218-E-12B Burial Ground to the surrounding surface- and groundwater. Burial of metal components containing nickel alloy steel and lead at this location may eventually result in release of lead to the subsurface environment, including groundwater aquifers that may be used for domestic and agricultural purposes in the future and, ultimately, to the Columbia River. The rate at which lead is transported to downgradient locations depends on a complex set of factors, such as climate, soil and groundwater chemistry, and the geologic and hydrologic configuration of the subsurface region between the burial ground and a potential receptor location. The groundwater transport analysis was conducted using a one-dimensional screening model with a relatively conservative matrix of parameters obtained from the hydrogeologic and geochemical studies.
Date: October 1, 1992
Creator: Rhoads, K.; Bjornstad, B.N.; Lewis, R.E.; Teel, S.S.; Cantrell, K.J.; Serne, R.J. et al.
Partner: UNT Libraries Government Documents Department

Estimation of the release and migration of lead through soils and groundwater at the Hanford Site 218-E-12B Burial Ground. Volume 2, Appendices

Description: This report describes the technical basis for a groundwater transport analysis that was conducted to evaluate migration of potentially hazardous materials from the Hanford Site 218-E-12B burial ground. The analysis characterized the geologic, chemical, and hydrologic properties of the disposal site, and used that information to perform a screening analysis for transport of materials from the burial ground to downgradient groundwater locations and to the Columbia River. Subsequent sections of the appendix describe the geologic setting, geochemistry, and hydrology of the disposal site and their relationship to the transport analysis.
Date: October 1, 1992
Creator: Rhoads, K.; Bjornstad, B. N.; Lewis, R. E.; Teel, S. S.; Cantrell, K. J.; Serne, R. J. et al.
Partner: UNT Libraries Government Documents Department

Estimation of the release and migration of lead through soils and groundwater at the Hanford Site 218-E-12B Burial Ground. Volume 1, Final report

Description: This study was performed to evaluate the potential for transport of lead from the Hanford Site 218-E-12B Burial Ground to the surrounding surface- and groundwater. Burial of metal components containing nickel alloy steel and lead at this location may eventually result in release of lead to the subsurface environment, including groundwater aquifers that may be used for domestic and agricultural purposes in the future and, ultimately, to the Columbia River. The rate at which lead is transported to downgradient locations depends on a complex set of factors, such as climate, soil and groundwater chemistry, and the geologic and hydrologic configuration of the subsurface region between the burial ground and a potential receptor location. The groundwater transport analysis was conducted using a one-dimensional screening model with a relatively conservative matrix of parameters obtained from the hydrogeologic and geochemical studies.
Date: October 1, 1992
Creator: Rhoads, K.; Bjornstad, B. N.; Lewis, R. E.; Teel, S. S.; Cantrell, K. J.; Serne, R. J. et al.
Partner: UNT Libraries Government Documents Department