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STREAM II-V4: Revision for STREAM II-V3 to Allow Mouse-Driven Selection of Release Location from a Graphical User Interface

Description: STREAM II-V3 is an aqueous transport module of the Savannah River Site emergency response Weather INformation Display (WIND) system. Stream II-V3 predicts peak concentration and peak concentration arrival time at downstream locations for releases from the SRS facilities to the Savannah River. Fifteen pre-determined potential release locations from SRS facilities were built into the current STREAM II-V3 model. Therefore, STREAM II-V3 can not be used for situations in which release locations differ from the fifteen pre-determined locations. To eliminate this limitation, STREAM II-V3 was upgraded. The revised STREAM II-V4 allows users to select the release location anywhere along the specified SRS main streams or the Savannah River by mouse clicking on a map displayed on the computer monitor.
Date: December 18, 2002
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Revised STREAM code benchmarking with 1991 K-reactor tritiated aqueous release incident

Description: The transport and diffusion module of the WIND System aqueous emergency response program (STREAM code) was replaced with the EPA WASP5 code. A set of input data was developed to model the transport of pollutants from a release point in K-Area to Savannah, Georgia through Indian Grave Branch, Pen Branch, the SRS swamp, Steel Creek, and the Savannah River. To evaluate the modifications to the STREAM code, data from an accidental release of tritiated water from K-Reactor in 1991 were used for benchmarking. A leak in a heat exchanger allowed a small amount of reactor coolant water to be released to cooling streams onsite, eventually reaching the Savannah River. Measurements of tritium concentration were taken at several downstream locations during the release. The results show that the revised STREAM code overpredicts the peak concentrations by 3 to 15%, which is comparable to the measurement uncertainty (one standard deviation). The revised STREAM code underpredicts the transport times of the concentration peak by 18 to 37%. The discrepancies in the travel time could result from uncertainties in the start of the release. The revised STREAM code performed well in simulating both the timing and the magnitude of the maximum observed tritium concentration. This gives confidence that the code can perform well both for emergency response and other engineering or safety analyses
Date: April 25, 1996
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Surface Water Modeling Using an EPA Computer Code for Tritiated Waste Water Discharge from the heavy Water Facility

Description: Tritium releases from the D-Area Heavy Water Facilities to the Savannah River have been analyzed. The U.S. EPA WASP5 computer code was used to simulate surface water transport for tritium releases from the D-Area Drum Wash, Rework, and DW facilities. The WASP5 model was qualified with the 1993 tritium measurements at U.S. Highway 301. At the maximum tritiated waste water concentrations, the calculated tritium concentration in the Savannah River at U.S. Highway 301 due to concurrent releases from D-Area Heavy Water Facilities varies from 5.9 to 18.0 pCi/ml as a function of the operation conditions of these facilities. The calculated concentration becomes the lowest when the batch releases method for the Drum Wash Waste Tanks is adopted.
Date: June 1, 1998
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

7Q10 flows for SRS streams

Description: The Environmental Transport Group of the Environmental Technology Section was requested to predict the seven-day ten-year low flow (7Q10 flow) for the SRS streams based on historical stream flow records. Most of the historical flow records for the SRS streams include reactor coolant water discharged from the reactors and process water released from the process facilities. The most straight forward way to estimate the stream daily natural flow is to subtract the measured upstream reactor and/or facility daily effluents from the measured downstream daily flow. Unfortunately, this method does not always work, as indicated by the fact that sometimes the measured downstream volumetric flow rates are lower than the reactor effluent volumetric flow rates. For those cases that cannot be analyzed with the simple subtracting method, an alternative method was used to estimate the stream natural flows by statistically separating reactor coolant and process water flow data. The correlation between the calculated 7Q10 flows and the watershed areas for Four Mile Branch and Pen Branch agrees with that calculated by the USGS for Upper Three Runs and Lower Three Runs Creeks. The agreement between these two independent calculations lends confidence to the 7Q10 flow calculations presented in this report.
Date: October 1, 1996
Creator: Chen, K. F.
Partner: UNT Libraries Government Documents Department

STREAM2 for Aqueous Release Emergency Response

Description: This report documents the STREAM2 code and its input models developed for the WIND System. STREAM2 is a modification of the STREAM code, which is the transport and diffusion module of the WIND System aqueous emergency response program. STREAM predicts downstream pollutant concentrations for releases from the Savannah River Site to the Savannah River. The STREAM calculation module uses an algebraic equation to approximate the solution of the differential one-dimensional advective transport equation. The advantage of this simplified approach is that the time required to obtain a solution is shortened to a matter of minutes. However, this approach generates spurious oscillations in the concentration profile when modeling long duration releases. To improve the capability of the STREAM code to model long-term releases, its calculation module was replaced by the transport module of the WASP5 code. WASP5 is a US EPA water quality analysis program that simulates pollutant transport and fate through surface water. The revised STREAM code is named STREAM2.
Date: September 23, 1998
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Benchmarking WASP5 with data from the 1991 K-Reactor tritiated aqueous release incident

Description: The Savannah River Site (SRS) has upgraded its aqueous emergency response capability to model the transport of pollutants released from SRS facilities during normal operation or accidents through onsite streams to the Savannah River. The transport and dispersion modules from the US Environmental Protection Agency (EPA) WASP5 model were incorporated into the SRS emergency response system, called the Weather Information and Display (WIND) System. WASP5 is a water quality analysis program that simulates surface water pollutant transport, using a finite difference method to solve the advective transport equation. Observed tritium concentrations in the SRS streams and the Savannah River from an accidental release from K-Reactor, one of the SRS nuclear material production reactors, were used to benchmark the new model. Although all SRS reactors have since been deactivated, this release of tritiated water occurred between December 22 and 25, 1991, through the K-Reactor secondary cooling water discharge. Analyses of reactor discharge water suggested the leak began sometime during December 22. The leak was positively identified and isolated on December 25. Following the release, tritium concentrations were tracked and measured as the tritiated water flowed from the K-Area outfall into Indian Grave Branch and pen Branch, through the Savannah River swamp, past the mouth of Steel Creek, and down the Savannah River. The measured tritium concentrations at Steel Creek, Highway 301, Becks Ferry and Abercorn Creek were used for benchmarking.
Date: November 7, 1996
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

STREAM2 Revision 1: An aqueous release emergency response model

Description: This report documents the revision for STREAM2 code and its input files. STREAM2 is an aqueous transport module of the WIND system. As requested by the Emergency Response Department, two surface aqueous release locations (McQueen Branch and Tims Branch) were added in the STREAM2 code. In addition, the revised STREAM2 has the capability to vary the channel-segment volume based on channel flow to better represent the open channel hydraulics. Thus, the updated version of STREAM2 improves the contaminant transport calculation
Date: April 14, 2000
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

1995 and 1996 Upper Three Runs Dye Study Data Analyses

Description: This report presents an analysis of dye tracer studies conducted on Upper Three Runs. The revised STREAM code was used to analyze these studies and derive a stream velocity and a dispersion coefficient for use in aqueous transport models. These models will be used to facilitate the establishment of aqueous effluent limits and provide contaminant transport information to emergency management in the event of a release.
Date: June 1998
Creator: Chen, K. F.
Partner: UNT Libraries Government Documents Department

Pen Branch Delta and Savannah River Swamp Hydraulic Model

Description: The proposed Savannah River Site (SRS) Wetlands Restoration Project area is located in Barnwell County, South Carolina on the southwestern boundary of the SRS Reservation. The swamp covers about 40.5 km2 and is bounded to the west and south by the Savannah River and to the north and east by low bluffs at the edge of the Savannah River floodplain. Water levels within the swamp are determined by stage along the Savannah River, local drainage, groundwater seepage, and inflows from four tributaries, Beaver Dam Creek, Fourmile Branch, Pen Branch, and Steel Creek. Historic discharges of heated process water into these tributaries scoured the streambed, created deltas in the adjacent wetland, and killed native vegetation in the vicinity of the delta deposits. Future releases from these tributaries will be substantially smaller and closer to ambient temperatures. One component of the proposed restoration project will be to reestablish indigenous wetland vegetation on the Pen Branch delta that covers about 1.0 km2. Long-term predictions of water levels within the swamp are required to determine the characteristics of suitable plants. The objective of the study was to predict water levels at various locations within the proposed SRS Wetlands Restoration Project area for a range of Savannah River flows and regulated releases from Pen Branch. TABS-MD, a United States Army Corps of Engineer developed two-dimensional finite element open channel hydraulic computer code, was used to model the SRS swamp area for various flow conditions.
Date: May 13, 1999
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

The Effect of Sedimentation on Plutonium Transport in Fourmile Branch

Description: The major mechanisms of radioactive material transport and fate in surface water are sources, dilution, advection and dispersion of radionuclides by flow and surface waves, radionuclide decay, and interaction between sediment and radionuclides. STREAM II, an aqueous transport module of the Savannah River Site emergency response WIND system, accounts for the source term, and the effects of dilution, advection and dispersion. Although the model has the capability to account for nuclear decay, due to the short time interval of interest for emergency response, the effect of nuclear decay is very small and so it is not employed. The interactions between the sediment and radionuclides are controlled by the flow conditions and physical and chemical characteristics of the radionuclides and the sediment constituents. The STREAM II version used in emergency response must provide results relatively quickly; it therefore does not model the effects of sediment deposition/resuspension. This study estimates the effects of sediment deposition/resuspension on aqueous plutonium transport in Fourmile Branch. There are no measured data on plutonium transport through surface water available for direct model calibration. Therefore, a literature search was conducted to find the range of plutonium partition coefficients based on laboratory experiments and field measurements. A sensitivity study of the calculated plutonium peak concentrations as a function of the input parameter of partition coefficient was then performed. Finally, an estimation of the plutonium partition coefficient was made for the Fourmile Branch.
Date: February 21, 2002
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

STREAM II-V3: Revision for STREAM II-V2 to Include the Sedimentation Effects on a Release from H-Area

Description: STREAM II, an aqueous transport module of the Savannah River Site emergency response Weather INformation Display (WIND) system, accounts for the effects of dilution, advection and dispersion. Although the model has the capability to account for nuclear decay, due to the short time interval of interest for emergency response, the effect of nuclear decay is very small and so it is not employed. The interactions between the sediment and radionuclides are controlled by the flow conditions and physical and chemical characteristics of the radionuclides and the sediment constituents. The STREAM II-V2 used in emergency response does not model the effects of sediment deposition/resuspension to minimize computing time. The effects of sedimentation on cesium and plutonium transport in the Fourmile Branch were studied recently and the results from these studies indicated that the downstream cesium and plutonium peak concentrations were significantly reduced due to the effects of sedimentations. The STREAM II-V2 was upgraded to account for the effect of sedimentation on aqueous transport of cesium and plutonium released from H-Area.
Date: February 21, 2002
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Revised STREAM code and WASP5 benchmark

Description: STREAM is an emergency response code that predicts downstream pollutant concentrations for releases from the SRS area to the Savannah River. The STREAM code uses an algebraic equation to approximate the solution of the one dimensional advective transport differential equation. This approach generates spurious oscillations in the concentration profile when modeling long duration releases. To improve the capability of the STREAM code to model long-term releases, its calculation module was replaced by the WASP5 code. WASP5 is a US EPA water quality analysis program that simulates one-dimensional pollutant transport through surface water. Test cases were performed to compare the revised version of STREAM with the existing version. For continuous releases, results predicted by the revised STREAM code agree with physical expectations. The WASP5 code was benchmarked with the US EPA 1990 and 1991 dye tracer studies, in which the transport of the dye was measured from its release at the New Savannah Bluff Lock and Dam downstream to Savannah. The peak concentrations predicted by the WASP5 agreed with the measurements within {+-} 20.0%. The transport times of the dye concentration peak predicted by the WASP5 agreed with the measurements within {+-} 3.6%. These benchmarking results demonstrate that STREAM should be capable of accurately modeling releases from SRS outfalls.
Date: May 1, 1995
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Flood Hazard Recurrence Frequencies for C-, F-, E-, S-, H-, Y-, and Z-Areas

Description: A method was developed to determine the probabilistic flood elevation curves for Savannah River Site facilities. This report presents the method used to determine the probabilistic flood elevation curves for C-, F-, E-, H-, S-, Y-, and Z-Areas due to runoff from the Upper Three Runs and Fourmile Branch basins.
Date: November 18, 1999
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Benchmarking of FLOWTRAN with Mark-22 mockup flow excursion test data from Babcock & Wilcox

Description: Version 16.2 of the FLOWTRAN code with a Savannah River Site (SRS) working criterion (St=0.00455) for the onset of significant void (OSV) was benchmarked against power and flow excursion data derived from tests at the Babcock & Wilcox Alliance Research Center test facility. The analyses show that FLOWTRAN accurately predicts the mockup test assembly thermal-hydraulic behavior during the steady state and LOCA transient conditions, and that FLOWTRAN with a Savannah River Site (SRS) working limits criterion (St=0.00455) conservatively predicts the OFI power. Results for LOCA simulations which include a power decay transient for a safety rod SCRAM are shown below. For all of these tests, the calculated test assembly initial power or operating power limit was at least 15% below the initial power level for which the test assembly went into flow instability. These calculations were made using the SRS LOCA FI limits methodology ada ted to the test assembly.
Date: November 1, 1991
Creator: Chen, K. F.
Partner: UNT Libraries Government Documents Department

Benchmarking of FLOWTRAN with Mark-22 mockup flow excursion test data from Babcock Wilcox

Description: Version 16.2 of the FLOWTRAN code with a Savannah River Site (SRS) working criterion (St=0.00455) for the onset of significant void (OSV) was benchmarked against power and flow excursion data derived from tests at the Babcock Wilcox Alliance Research Center test facility. The analyses show that FLOWTRAN accurately predicts the mockup test assembly thermal-hydraulic behavior during the steady state and LOCA transient conditions, and that FLOWTRAN with a Savannah River Site (SRS) working limits criterion (St=0.00455) conservatively predicts the OFI power. Results for LOCA simulations which include a power decay transient for a safety rod SCRAM are shown below. For all of these tests, the calculated test assembly initial power or operating power limit was at least 15% below the initial power level for which the test assembly went into flow instability. These calculations were made using the SRS LOCA FI limits methodology ada ted to the test assembly.
Date: November 1, 1991
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

THE APPLICATION OF A STATISTICAL DOWNSCALING PROCESS TO DERIVE 21{sup ST} CENTURY RIVER FLOW PREDICTIONS USING A GLOBAL CLIMATE SIMULATION

Description: The ability of water managers to maintain adequate supplies in coming decades depends, in part, on future weather conditions, as climate change has the potential to alter river flows from their current values, possibly rendering them unable to meet demand. Reliable climate projections are therefore critical to predicting the future water supply for the United States. These projections cannot be provided solely by global climate models (GCMs), however, as their resolution is too coarse to resolve the small-scale climate changes that can affect hydrology, and hence water supply, at regional to local scales. A process is needed to ‘downscale’ the GCM results to the smaller scales and feed this into a surface hydrology model to help determine the ability of rivers to provide adequate flow to meet future needs. We apply a statistical downscaling to GCM projections of precipitation and temperature through the use of a scaling method. This technique involves the correction of the cumulative distribution functions (CDFs) of the GCM-derived temperature and precipitation results for the 20{sup th} century, and the application of the same correction to 21{sup st} century GCM projections. This is done for three meteorological stations located within the Coosa River basin in northern Georgia, and is used to calculate future river flow statistics for the upper Coosa River. Results are compared to the historical Coosa River flow upstream from Georgia Power Company’s Hammond coal-fired power plant and to flows calculated with the original, unscaled GCM results to determine the impact of potential changes in meteorology on future flows.
Date: August 22, 2013
Creator: Werth, D. & Chen, K. F.
Partner: UNT Libraries Government Documents Department

From the LHC to Future Colliders

Description: Discoveries at the LHC will soon set the physics agenda for future colliders. This report of a CERN Theory Institute includes the summaries of Working Groups that reviewed the physics goals and prospects of LHC running with 10 to 300 fb{sup -1} of integrated luminosity, of the proposed sLHC luminosity upgrade, of the ILC, of CLIC, of the LHeC and of a muon collider. The four Working Groups considered possible scenarios for the first 10 fb{sup -1} of data at the LHC in which (i) a state with properties that are compatible with a Higgs boson is discovered, (ii) no such state is discovered either because the Higgs properties are such that it is difficult to detect or because no Higgs boson exists, (iii) a missing-energy signal beyond the Standard Model is discovered as in some supersymmetric models, and (iv) some other exotic signature of new physics is discovered. In the contexts of these scenarios, theWorking Groups reviewed the capabilities of the future colliders to study in more detail whatever new physics may be discovered by the LHC. Their reports provide the particle physics community with some tools for reviewing the scientific priorities for future colliders after the LHC produces its first harvest of new physics from multi-TeV collisions.
Date: June 11, 2010
Creator: De Roeck, A.; Ellis, J.; Grojean, C.; Heinemeyer, S.; Jakobs, K.; Weiglein, G. et al.
Partner: UNT Libraries Government Documents Department