[en] The Brookhaven Graphite Research Reactor (BGRR), which operated from 1951--1968 is currently undergoing decontamination and decommissioning (D and D). As part of this effort, many of the major structures and facilities (e.g., Above Grade Ducts, Cooling Fans, Pile Fan Sump, Transfer Canal and Instruments Houses) are being removed to eliminate contaminants and reduce the footprint of the overall facility. However, a significant cost savings (almost $5M) can potentially be realized if the large concrete Below Grade Ducts (BGD) can be decontaminated and left in place. In order to do this, soils beneath the ducts must be fully characterized to identify areas where contaminants may have leaked, what radioactive and hazardous contaminants remain, and in what concentrations. This information will then be used to evaluate whether discrete areas of localized contaminated soil can be selectively removed or, if the contamination is significant and widespread, and whether the ducts themselves must be removed for complete cleanup. The information generated from this effort is input into the BGRR BGD Characterization Report and an Engineering Evaluation/Cost Analysis (EE/CA) currently being prepared to evaluate potential options for the ducts. This FY01 Department of Energy Accelerated Site Technology Deployment (DOE ASTD) project combined a suite of innovative technologies to provide cost-effective characterization of the soils beneath the BGD and present the data in an easily understandable three-dimensional representation of the contaminant concentrations beneath the ducts. Conventional characterization of the soil would have required sampling a very large area in a tight grid pattern to ensure that all areas of potential contamination were evaluated. It is estimated that using baseline techniques would require approximately 2500 samples (costing ∼$1.6M), depending on the level of precision required by regulators. This massive amount of data would then be difficult to manipulate and interpret in order to evaluate the extent of excavation required. The alternative approach deployed for this ASTD began with a novel perfluorocarbon tracer (PFT) gas study to determine the potential leak pathways for contaminated water exiting the BGD. The results of the PFT test successfully identified areas where contaminated soil may be located. The Sampling and Analysis Plan (SAP) was then designed to focus on these areas, while taking fewer samples for confirmatory analyses in areas thought to be clean

[en] Over 1,140 yd³ of radioactively contaminated soil containing toxic mercury (Hg) and several liters of mixed-waste elemental mercury were generated during a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) removal action at Brookhaven National Laboratory (BNL). The US Department of Energy's (DOE) Office of Science and Technology Mixed Waste Focus Area (DOE MWFA) is sponsoring a comparison of several technologies that may be used to treat these wastes and similar wastes at BNL and other sites across the DOE complex. This report describes work conducted at BNL on the application and pilot-scale demonstration of the newly developed Sulfur Polymer Stabilization/Solidification (SPSS) process for treatment of contaminated mixed-waste soils containing high concentrations (approximately 5,000 mg/L) of mercury and liquid elemental mercury. BNL's SPSS (patent pending) process chemically stabilizes the mercury to reduce vapor pressure and leachability and physically encapsulates the waste in a solid matrix to eliminate dispersion and provide long-term durability. Two 55-gallon drums of mixed-waste soil containing high concentrations of mercury and about 62 kg of radioactive contaminated elemental mercury were successfully treated. Waste loadings of 60 wt% soil were achieved without resulting in any increase in waste volume, while elemental mercury was solidified at a waste loading of 33 wt% mercury. Toxicity Characteristic Leaching Procedure (TCLP) analyses indicate the final waste form products pass current Environmental Protection Agency (EPA) allowable TCLP concentrations as well as the more stringent proposed Universal Treatment Standards. Mass balance measurements show that 99.7% of the mercury treated was successfully retained within the waste form, while only 0.3% was captured in the off gas system

[en] A research program has been under way at the Brookhaven National Laboratory to investigate the radionuclide release behavior of ion exchange bead resin waste solidified in Portland cement. An important aspect of this program is to develop and evaluate testing procedures and methodologies which enable the long-term performance evaluation of waste forms under simulated field conditions. Cesium and strontium release behavior using a range of testing procedures, including intermittent leachant flow conditions, has been investigated. For cyclic wet/dry leaching tests, extended dry periods tend to enhance the release of Cs and suppress the release of Sr. Under extended wet period leaching conditions, however, both Cs and Sr exhibit suppressed releases. In contrast, radionuclide releases observed under continuously saturated leaching conditions, as represented by conventional leaching tests, are significantly different. The relevance and aplicability of these laboratory data obtained under a wide range of leaching conditions to the performance evaluation of waste forms under anticipated field conditions is discussed. 12 refs., 9 figs., 3 tabs

[en] The Brookhaven Graphite Research Reactor is currently on an accelerated decommissioning schedule with a completion date projected for 2005. The accelerated schedule combines characterization with removal actions for the various systems and structures. A major project issue involves characterization of the soils beneath contaminated Below Grade Ducts (BGD), the main air ducts connecting the exhaust plenums with the Fan House. The air plenums experienced water intrusion during BGRR operations and after shutdown. The water intrusions were attributed to rainwater leaks into degraded parts of the system, and to internal cooling water system leaks. If the characterization could provide enough information to show that soil contamination surrounding the BGD is either below cleanup guidelines or is very localized and can be ''surgically removed'' at a reasonable cost, the ducts may be decontaminated and left in place. This will provide significant savings compared to breaking up the 170-ft. long concrete duct, shipping the projected 9,000 m³ of waste off-site and disposing of it in an approved site

[en] A research program has been underway at the Brookhaven National Laboratory to investigate the release of radionuclides from low-level waste forms under laboratory conditions. This paper describes the leaching behavior of Cs-137 from two major low-level waste streams, that is, ion exchange bead resin and boric acid concentrate, solidified in Portland cement. The resultant leach data are employed to evaluate and predict the release behavior of Cs-137 from low-level waste forms under field burial conditions

[en] A study correlating the leachability of ¹³⁷Cs from small-scale to large-scale cement forms was performed. The waste forms consisted of (a) organic ion exchange resins incorporated in Portland I cement, with a waste-to-cement ratio of 0.6 and a water-to-cement ratio of 0.4 (as free water) and (b) boric acid waste (12% solution) incorporated in Portland III cement, with a waste-to-cement ratio of 0.7. ¹³⁷Cs was added to both waste types prior to solidification. The sample dimensions varied from 1 in. x 1 in. to 22 in. x 22 in. (diameter x height). Leach data extending over a period of 260 days were obtained using a modified IAEA leach test. A method based on semi-infinite plane source diffusion model was applied to interpret the leach data. A derived mathematical expression allows prediction of the amount of ¹³⁷Cs leached from the forms as a function of leaching time and waste form dimensions. A reasonably good agreement between the experimental and calculated data was obtained. 4 figures, 6 tables

[en] During operation of light water reactors, corrosion of metallic components in the primary system occurs. Corrosion products are circulated through the system by the coolant, and some become radioactive as a result of neutron activation in the core. After years of operation, deposition of the corrosion products within the primary system leads to a steady increase in radiation levels. This, in turn, causes increasing difficulty during routine maintenance of the plant because of worker exposure to radiation. One task was created to determine chemical and physical conditions which could lead to thermal excursion, gas generation, and/or general degradation of waste ion-exchange resins used for clean-up at nuclear power plants. This work will provide information to allow determination of whether such events could happen in the future, either during storage or processing at the plant, during transportation not at the final disposal site. Another task was initiated to evaluate the compatibility of a range of container materials with a simulated decontamination resin waste. It was found the corrosion of carbon steel and austenitic stainless steel in mixed bed resins is enhanced by gamma irradiation. However, cracking in high density polyethylene is essentially eliminated

[en] This report describes a DOE Accelerated Site Technology Deployment project being conducted at Brookhaven National Laboratory to deploy innovative, radiological, in situ analytical techniques. The technologies are being deployed in support of efforts to characterize the Brookhaven Graphite Research Reactor (BGRR) facility, which is currently undergoing decontamination and decommissioning. This report focuses on the deployment of the Canberra Industries In Situ Object Counting System (ISOCS) and assesses its data comparability to baseline methods of sampling and laboratory analysis. The battery-operated, field deployable gamma spectrometer provides traditional spectra of counts as a function of gamma energy. The spectra are then converted to radionuclide concentration by applying innovative efficiency calculations using monte carlo statistical methods and pre-defined geometry templates in the analysis software. Measurement of gamma emitting radionuclides has been accomplished during characterization of several BGRR components including the Pile Fan Sump, Above Ground Ducts, contaminated cooling fans, and graphite pile internals. Cs-137 is the predominant gamma-emitting radionuclide identified, with smaller quantities of Co-60 and Am-241 detected. The Project used the Multi-Agency Radiation Survey and Site Investigation Manual guidance and the Data Quality Objectives process to provide direction for survey planning and data quality assessment. Analytical results have been used to calculate data quality indicators (DQI) for the ISOCS measurements. Among the DQIs assessed in the report are sensitivity, accuracy, precision, bias, and minimum detectable concentration. The assessment of the in situ data quality using the DQIs demonstrates that the ISOCS data quality can be comparable to definitive level laboratory analysis when the field instrument is supported by an appropriate Quality Assurance Project Plan. A discussion of the results obtained by ISOCS analysis of objects that could not be analyzed readily by conventional methods demonstrates a powerful application of the instrument. In conclusion, a comparison of costs associated with the analysis on the ISOCS instrument to the costs of conventional sampling and laboratory analysis is presented

[en] This report describes work conducted by BNL on the degradation of simulated chemical decontamination wastes by combustion and acid digestion. Both acid digestion and combustion are capable of effecting approx.90% destruction of the materials studied, as measured by the conversion of carbon compounds in the waste to carbon dioxide. Work on the direct modification of simulated decontamination wastes in cement and vinyl ester-styrene is reported also. Laboratory scale waste forms were prepared using these binders

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