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Harris, Stephen P.

Publications and source records attributed to Harris, Stephen P..

STATISTICAL ANALYSIS OF IN-SERVICE ULTRASONIC INSPECTION DATA OF WASTE TANKS AT THE SAVANNAH RIVER Site-25021

Liquid radioactive waste has been stored in large, underground carbon steel tanks of 4.92-million-liter capacity at the United States Department of Energy's Savannah River Site (SRS) in Aiken, South Carolina since the 1950s. The In-service inspection of the Savannah River Site High Level Waste tanks will be reviewed as well as Ultrasonic testing (UT) for detecting for general wall thinning, pitting and interface attack through accessible regions of the tanks. In-service inspection [1] of the Savannah River Site (SRS) High Level Waste (HLW) tanks is an essential element of a comprehensive structural integrity program. Inspection confirmed the effectiveness of chemistry and temperature controls used to preclude localized and general corrosion of the tanks. Ultrasonic testing is used to detect general wall thinning, pitting and interface attack, as well as vertically oriented cracks through inspection of a 21.59 cm (8.5-in.) wide strip extending over the accessible height of the primary tank wall.

Harris, Stephen P.↗

Testing of the Defense Waste Processing Facility Cold Chemical Dissolution Method in Sludge Batch 10 Qualification

For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) tests the applicability of the digestion methods used by the DWPF Laboratory for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) Receipt samples and SRAT Product process control samples. DWPF SRAT samples are typically dissolved using a method referred to as the DWPF Cold Chemical or Cold Chem Method (CC), (see DWPF Procedure SW4-15.201- 2.1).

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Relationship Between the Marginal Probability of Failure for a CPP Test and the Recommended Corrosion Control Requirements for Hanford Double Shell Waste Tanks

The Hanford Site in Washington State currently stores millions of gallons of radioactive waste in underground, carbon steel, double shell tanks (DSTs) that were constructed between 1968 and 1986. A chemistry control and monitoring program has been established mitigate corrosion in order to extend the service life for the DSTs. The current waste temperatures in the DSTs are at historical lows (i.e., typically less than 50 °C). The previous chemistry control requirements were determined for conditions at temperatures significantly higher. SRNL undertook a statistically based investigation of the role of nitrate and halide ion (i.e., chloride and fluoride) induced pitting corrosion. The objective was to develop a comprehensive waste chemistry envelope for the simultaneous minimization of the pitting and SCC risks caused by halide and nitrate ions at the lower temperature conditions. On the basis of these tests, new chemistry control requirements were proposed and have since been implemented for pitting corrosion control.

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Ion Chromatography (IC) Round Robin Analyses of Low Glycolate Concentrations in Recycle Collection Tank (RCT) Post Permanganate Treatment Simulant

This work is a demonstration of Ion Chromatography (IC) analysis of low concentrations of glycolate in chemical simulant designed to mimic the matrix in the Recycle Collection Tank (RCT) at the Defense Waste Processing Facility (DWPF) after sodium permanganate oxidation treatment. The IC method was previously developed [1] and this report covers the results of round robin testing with three analytical laboratories located at the Savannah River Site (SRS). The laboratories are termed the Sensing & Metrology (S&M) laboratory at the Savannah River National Laboratory (SRNL), the Processing Science Analytical Laboratory (PSAL) at SRNL, and the DWPF laboratory at SRS. Each laboratory received four samples: (1) 200 mL of 21.3 mg/L glycolate in RCT post permanganate strike sulfite quenched simulant, (2) 200 mL of 38.0 mg/L glycolate in RCT post permanganate strike sulfite quenched simulant, (3) 200 mL of 54.9 mg/L glycolate in RCT post permanganate strike sulfite quenched simulant, and (4) 600 mL of RCT post permanganate strike sulfite quenched simulant to use for matrix matched blanks.

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Modeling the Destruction of Glycolate in the Defense Waste Processing Facility (DWPF) Recycle Stream and Concentration Factors for Glycolate in the 2H Evaporator

Two models were developed to predict maximum glycolate concentrations in the Savannah River Site (SRS) Concentration, Storage, and Transfer Facility (CSTF) from implementation of the Nitric-Glycolic flowsheet at the Defense Waste Processing Facility (DWPF). One model describes the kinetics of glycolate destruction via chemical oxidation with sodium permanganate. This model conservatively predicts glycolate concentration delivered to the CSTF with a high probability the actual glycolate concentration is lower than predicted. The second model describes the potential concentration of said residual glycolate within the 242-16H (i.e., “2H”) Evaporator system.

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