Executive SummaryThe Hanford Site in Washington State manages 177 underground storage tanks containing approximately 250,000 m 3 of waste generated during past defense reprocessing and waste management operations. These tanks contain a mixture of sludge, saltcake and supernatant liquids. The insoluble sludge fraction of the waste consists of metal oxides and hydroxides and contains the bulk of many radionuclides such as the transuranic components and 90 Sr. The saltcake, generated by extensive evaporation of aqueous solutions, consists primarily of dried sodium salts. The supernates consist of concentrated (5-15 M) aqueous solutions of sodium and potassium salts. The 177 storage tanks include 149 single-shell tanks (SSTs) and 28 double-shell tanks (DSTs).Ultimately the wastes need to be retrieved from the tanks for treatment and disposal. The SSTs contain minimal amounts of liquid wastes, and the Tank Operations Contractor is continuing a program of moving solid wastes from SSTs to interim storage in the DSTs. The Hanford DST system provides the staging location for waste feed delivery to the Department of Energy (DOE) Office of River Protection's (ORP) Hanford Tank Waste Treatment and Immobilization Plant (WTP). The WTP is being designed and constructed to pretreat and then vitrify a large portion of the wastes in Hanford's 177 underground waste storage tanks.The retrieval, transport, treatment and disposal operations involve the handling of a wide range of slurries. Solids in the slurry have a wide range of particle size, density and chemical characteristics. Depending on the solids concentration the slurries may exhibit a Newtonian or a non-Newtonian rheology.The extent of knowledge of the physical and rheological properties is a key component to the success of the design and implementation of the waste processing facilities. These properties are used in engineering calculations in facility designs. Knowledge of the waste properties is also necessary for the development and fabrication of simulants that are used in testing at various scales. The expense and hazards associated with obtaining and using actual wastes dictates that simulants be used at many stages in the testing and scale-up of process equipment. The results presented in this report should be useful for estimating process and equipment performance and provide a technical basis for development of simulants for testing.The purpose of this document is to provide an updated summary of the Hanford waste characterization data pertinent to safe storage, retrieval, transport and processing operations for both the tank farms and the WTP and thereby identify gaps in understanding and data. Important waste parameters for these operations are identified by examining examples of relevant mathematical models of selected phenomena including: The data sets in (UDS composition and particle density, UDS primary particle size and shape, UDS particle size distributions [PSDs], and estimated particle size and density distributions [PSDDs]) and Poloski et al. (2007) ...
the equipmentand expertise to characterize gases and vapors in the high-level radioactive waste storage tanks at the Hanford Site in south central Washington State. This capability has been demonstratedby the characterizationof the tank 24I-C-103 headspace. This tankheadspace is the first, and for many reasons is expected to be the most problematic, that will be characterized (Osborne 1992). Results from the most recent and comprehensive sampling event, sample job 713,are presented for the purpose of providing scientific bases for resolution of vapor issues associated with tank 241-C-103. This report is based on the work of Clauss et al. 1994,
This report presents the results of ventilation rate studies of eight passively ventilated high-level radioactive waste tanks using tracer gases. Headspace ventilation rates were determined for Tanks A-101, AX-102, AX-103, BY-105, C-107, S-102, U-1 03, and U-105 using sulfur hexafluoride (SF,) and/or helium (He) as tracer gases. Passive ventilation rates are needed for the resolution of several key safety issues. These safety issues are associated with the rates of flammable gas production and ventilation, the rates at which organic salt-nitrate salt mixtures dry out, and the estimation of organic solvent waste surface areas. This tracer gas study involves injecting a tracer gas into the tank headspace and measuring its concentration at different times to establish the rate at which the tracer is removed by ventilation. Tracer gas injection and sample collection were performed by SGN Eurisys Service Corporation and/or Lockheed Martin Hanford Corporation, Characterization Project Operations. Headspace samples were analyzed for He and SF, by Pacific Northwest National Laboratory (PNNL). The tracer gas method was first demonstrated on Tank S-102. Tests were conducted on Tank S-102 to verify that the tracer gas was uniformly distributed throughout the tank headspace before baseline samples were collected, and that mixing was sufficiently vigorous to maintain an approximately uniform distribution of tracer gas in the headspace during the course of the study. Headspace samples, collected from a location about 4 m away from the injection point and 15,30, and 60 minutes after the injection of He and SF,, indicated that both tracer gases were rapidly mixed. The samples were found to have the same concentration of tracer gases after 1 hour as after 24 hours, suggesting that mixing of the tracer gas was essentially complete within 1 hour. Given this evidence for vigorous mixing, inhomogeneities produced by the influx of fresh air during normal ventilation would be expected to be restricted to a small region near the influx.
Since 1987, workers at the Hanford Site waste tank farms in Richland, Washington, have reported strong odors emanating from the large, underground high-level radioactive waste storage tanks. Some of these workers have complained of symptoms (e.g., headaches, nausea) related to the odors. In 1992, the U.S. Department of Energy, which manages the Hartford Site, and Westinghouse Hanford Company determined that the vapor emissions coming from the tanks had not been adequately characterized and represented a potential health risk to workers in the immediate vicinity of the tanks. At that time, workers in certain areas of the tank farms were required to use full-face, supplied-breathing-air masks to reduce their exposure to the fugitive emissions. While use of supplied breathing air reduced the health risks associated with the fugitive emissions, it introduced other health and safety risks (e.g., reduced field of vision, airline tripping hazards, and heat stress). Ii, 1992, an aggressive program was established to assure proper worker protection while reducing the use of supplied breathing air. This program focuses on characterization of vapors inside the tanks and industrial hygiene monitoring in the tank farms. If chemical filtration systems for mitigation of fugitive emissions are deemed necessary, the program will also oversee their design and installation. This document presents the plans for and approach to resolving the Hanford Site high-level waste tank vapor concerns. It is sponsored by the Department of Energy Office of Environmental Restoration and Waste Management.
Intensities of light scattered in the planes parallel and perpendicular to the polarization plane of the incident light are used to determine the size, refractive index, and dispersion of a single droplet suspended in an electrodynamic balance. Wavelengths of TE- and TM-mode resonances are determined independently with high precision when a ring dye laser is scanned. Resonating wavelengths are matched with theoretical intensity peaks to determine the constants of a dispersion formula and the size that minimizes the difference between observed and calculated wavelengths. The procedure permits the determination of the size and refractive index with relative errors of 3 × 10(-5) and dispersion with an absolute error 2 × 10(-5) over the experimental spectral range.
In Fiscal Year (FY) 1995, staff at the Vapor Analytical Laboratory (VAL) at Pacific Northwest National Laboratory (PNL) performed work in support of characterizing the vapor composition of the headspaces of radioactive waste tanks at the Hanford Site in Southeastern Washington. The work was supported by the Westinghouse Hanford Company (WHC) Tank Waste Remediation System ("WRS) Characterization Program and the U.S. Department of Energy's Richland Operations Office (DOEM.,). Work performed included support for technical issues and sampling methodologies, upgrades for analytical equipment, analytical method development, preparation of unexposed samples, dnalyses of tank headspace samples, preparation of data reports, preparation of input for WHC tank characterization reports, and operation of the tank vapor database. Work performed in FY 1995 was a continuation of work initiated with the first vapor sample job, which was performed in December 1993. Progress made in F Y 1995 included completion of sample analyses from all 40 jobs performed during the year, plus back-logged sample sets from jobs performed in F T 1994. Of the
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