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Castleberry, J. L.

Publications and source records attributed to Castleberry, J. L..

Inspection Technology Advancements for Hanford Double Shell Tank Integrity Verification - 16150

The Hanford double-shell tanks (DSTs) were constructed in southeastern Washington State between 1968 and 1986 to store nuclear waste. Most of the tank waste came from the Hanford nuclear weapons program, which has been stopped for more than 25 years. The tanks will be needed for many years to come until suitable vitrification and permanent storage solutions are developed. These tanks are nominally 45 ft. deep from the dome peak to the floor. The inner tank is nominally 75 ft. dia. and the outer tank is nominally 80 ft. dia., leaving a 2.5 ft. annulus between the two side tank walls. The waste management program (under direction of Washington River Protection Solutions, WRPS) manages inspections of these DSTs from the annulus to justify their continued safe service and to avoid the high cost of new replacement tanks. Over time, the Hanford Tank Farm contractors, currently WRPS, have increased their ultrasound inspections of these tanks. Pacific Northwest National Laboratory has worked with the Hanford Tank Farm contractors for more than 15 years to advance applicable tank nondestructive inspection technology for improved performance and cost reduction. Past, present, and planned technology advancements are addressed in this paper, including tank wall ultrasonic testing examination, extreme value statistical analysis, phased array for the tank wall, transmit/receive tandem synthetic aperture focusing technique knuckle examination, and electromagnetic acoustic transducer screening of the tank wall including mill-scale compensation. (authors)

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Determination of Erosion/Corrosion Rates in Hanford Tank Farms Radioactive Waste Transfer System Pipelines

The twenty-eight double-shell underground radioactive waste storage tanks at the U. S. Department of Energy’s Hanford Site near Richland, WA are interconnected by the Waste Transfer System network of buried steel encased pipelines and pipe jumpers in below-grade pits. The pipeline material is stainless steel or carbon steel in 51 mm to 152 mm (2 in. to 6 in.) sizes. The pipelines carry slurries ranging up to 20 volume percent solids and supernatants with less than one volume percent solids at velocities necessary to prevent settling. The pipelines, installed between 1976 and 2011, were originally intended to last until the 2028 completion of the double-shell tank storage mission. The mission has been subsequently extended. In 2010 the Tank Operating Contractor began a systematic evaluation of the Waste Transfer System pipeline conditions applying guidelines from API 579-1/ASME FFS-1 (2007), Fitness-For-Service. Between 2010 and 2014 Fitness-for-Service examinations of the Waste Transfer System pipeline materials, sizes, and components were completed. In parallel, waste throughput histories were prepared allowing side-by-side pipeline wall thinning rate comparisons between carbon and stainless steel, slurries and supernatants and throughput volumes. The work showed that for transfer volumes up to 6.1E+05 m 3 (161 million gallons), the highest throughput of any pipeline segment examined, there has been no detectable wall thinning in either stainless or carbon steel pipeline material regardless of waste fluid characteristics or throughput. The paper describes the field and laboratory evaluation methods used for the Fitness-for-Service examinations, the results of the examinations, and the data reduction methodologies used to support Hanford Waste Transfer System pipeline wall thinning conclusions.

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Double-Shell tank Integrity program - 15533

Waste at Hanford is stored in 149 single-shell tanks and 28 double-shell tanks (DSTs). Concerns related to aging radioactive waste storage facilities throughout the US DOE complex led to Brookhaven National Laboratory (BNL) developing guidelines for structural integrity programs for tank systems (BNL-52527, Guidelines for Development of Structural Integrity Programs for DOE High-Level Waste Storage Tanks). The committee of experts who developed these guidelines is commonly known as the Tank Structural Integrity Panel (TSIP). The US DOE has subsequently adopted these guidelines, and requires site operators to have a program consistent with them (DOE M 435.1, Radioactive Waste Management Manual). The Washington River Protection Solutions, LLC (WRPS) manages the tanks for the US DOE Office of River Protection (ORP) under the Tank Operations Contract (TOC). The US DOE-ORP contractual agreement with the TOC (11-NSD-010) includes a requirement to 'maintain the tank structural integrity program as described in RPP-7574, Double-Shell tank Integrity Project Plan'. The DST integrity is maintained with a variety of activities such as ultrasonic and visual inspections, chemistry controls, corrosion monitoring and structural analyses methods. The recent loss of tank 241-AY-102 has led to the formation of the High-Level Waste Integrity Assessment Panel to evaluate the DST integrity project (DSTIP) and to recommend improvements to the DSTIP. This panel continues the DOE practice of seeking expert advice to guide the formulation and continuous assessment of tank integrity activities. The panel has concluded its work and WRPS has developed a series of tasks to implement their recommendations. (authors)

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