DIAL's Research Highlights
Diagnostic Instrumentation & Analysis Laboratory
Support of Closure Sites
Fernald Silos Project Monitoring and Control Integration
Waste disposition. Activities for disposing of the remaining Fernald K-65 material, the grout samples, the laboratory trash, and the building trash were completed. Nine drums of material were delivered back to the Fernald site for treatment and disposal. The following activities are planned for the upcoming months:
Accelerating Phytoremediation by Monitoring Plant Status
During the month of December, we analyzed samples and data from previous experiments. We submitted a manuscript on mercury phytoremediation to a refereed journal for publication.
Bio-availability and Speciation of Mercury in the Oak Ridge Ecosystem
In December, we continued to conduct pilot scale experiments to study the bioavailability and kinetics of different mercury species (such as nitrate, chloride, elemental and sulfide) in Oak Ridge soil at three moisture regimes. We finished the fourth set of sampling. Mercury in extracts of all solid-phase components (totaling 1200 samples) was analyzed by ICP-AES or CVAAS.
In January, we will get some field contaminated soil samples from Oak Ridge. We will start to calculate and summarize the progress of the pilot scale experiments.
Support of Hanford Single Shell Tank Waste Disposition
In-tank/At-tank Characterization for Closure of Hanford Tanks
Stereovision. This month, we continued optimizing the operational parameters of our recently upgraded stereovision system.
Laser-induced fluorescence-spectral imaging. During December, we continued our experiments on simple uranyl compounds mixed at a variety of concentrations with other solid materials (in this case, sand). These experiments will enable us to determine the limits of detection for LIF spectral imaging detection of uranyl compounds in mixtures.
Microwave-induced plasma-cavity ringdown spectroscopy. The manufacturer has not yet fixed our UV spectrometer. We have been analyzing data from previously performed experiments. Experimental work will resume once the spectrometer is fixed.
Fiber optic sensors. During December, the fiber optic sensors effort has been working on improving the computer program used to read the photomultiplier tube signal. The program that we have verified is capable of continuously producing a graphic display that indicates the signal count and also a digital display of the number of counts on the computer screen. This is much more convenient for performing experiments than the previous computer program, which only displayed the signal count number following an instruction from the key board.
Fourier transform profilometry. This month, we had a conference call with our collaborators at Hanford in order to discuss the possibility of utilizing camera systems like those that Hanford has previously used; this would facilitate acceptance of the FTP system and would permit the camera system to be used for both FTP measurements and monitoring in-tank retrieval. The decision was made to take advantage of FTP system testing at DIAL and/or at the TVA Regenesys tank facility to collect data that would permit a side-by-side comparison of FTP with the approved procedure currently used at Hanford.
In addition, the FTP team deployed a submergible FTP system this month in the Oak Ridge Research Reactor (ORRR) pool in order to characterize the depth of the pit corrosion in the aluminum pool liner; this information will enable ORNL to make decisions about the schedule for demolition of the ORRR.
Process Chemistry and Operations Planning for Hanford Waste Alternatives
Reviewer comments were received for the manuscript entitled "Modeling of Pilot-Scale Salt Cake Dissolution." Efforts are being directed to the editor's recommendations with final submission of the paper scheduled for mid-January.
Additional gaps have been found in the neural network representation and associated calculations are currently in progress. We are awaiting additional directions from CH2M Hill as to expected work scope revisions.
Preliminary data from the latest pilot-scale salt cake dissolution experiment conducted at FIU has been received and modeling of the simulant preparation has begun.
Flexible Scintillating Optical Fiber Sensor for Determination of Liquid Level
We are working on improving the computer program to read the PMT signal. The verified program is capable of continuously giving out a graphic counting signal and the number of counts on the computer screen. This is much more convenient for experiments compared to the previous computer program, which only giving a counting number upon an input instruction from the keyboard.
Disposition of Idaho HLW Calcine
Support of ICP-SP3 Calcine Disposition Project
The annual report was completed and signed off. We received the site's recommendation for the next set of tests and will be starting on them next month. The PCT results for the most recent samples are given below. All passed.
Support of SRS Salt Disposition and Other SRS Alternatives
Support for SRS Salt Disposition Alternatives
Potassium nitrate/sodium hydroxide and cesium nitrate/sodium hydroxide solutions prepared at 50°C have reached equilibrium. Analytical results, when received, will be compared to literature data and upon completion will undergo statistical analysis.
The DASR small column experiment using SRS 38H simulant with sludge is continuing at 30°C in the environmental chamber and a total of 25 fractions have been collected to date. All fractions collected contain a small weight percent of solids appearing to result from the insoluble components contained in the sludge. Upon completion of the experiment, fractions will be separated for chemical analysis.
On-line Analysis for Defense Waste Processing Facility
One major problem related to the slurry measurement with LIBS is the sample splitting from the slurry surface due to laser-induced shock wave. It results in sample loss and the possibility of contamination of the optics. To solve this problem, we are testing various sampling configurations. Work also concentrated on the analysis of the composition of the simulated LRM (the low-activity reference material) glass obtained from DWPF. The sample was present in the form of tiny grains. Due to the rough surface formed by the tiny glass grains, the lens-to-sample distance varies during the measurement and results in a relatively poor precision (~ 5 - 10%). To achieve the best signal-noise-ratio of LIBS data and better precision, experiment parameters such as laser power, gate delay and width, the distance between lens and sample were studied for this sample. Using a broadband detection for the simulated LRM sample, we were able to simultaneous identify all the elements listed in the reference document. The feasibility study on using the standard glass LIBS data to calibrate the slurry data are also underway.
Support of Production of High Waste Loading Glasses in the DWPF
Progress on this task will be reported at a later date.
HEPA Filter Performance Assurance
Regenerable HEPA Filter Performance Testing
Continued HEPA filter media velocity testing was to be the focus of the HEPA group during the month of December. A media velocity test at 3 ft/min was begun on December 5, but was not completed due to instrument failure. The laser system of the PMS laser particle counter used to measure downstream particle size distributions did not appear to be working. The instrument was broken during trouble shooting procedures and must be sent back to the manufacturer for repairs.
Inquiries may be addressed to:Dr. Roger King, Interim Director
205 Research Blvd.
Starkville, MS 39762-5932