[en] A miniature laser-triggered high-voltage vacuum switch with a fused KCl and Ni cathode has been developed. The switch uses metal-ceramic construction with a sapphire window in the anode to allow the laser beam to strike the cathode surface. Reliable triggering is achieved with only 20 μJ of laser energy. The switch was operated with a gap voltage ranging from 500 V to 3 kV, with switching currents up to a 5-Ka peak. Switch life greater than 1000 shots without performance degradation has been observed on 50 prototype devices. The function time of the switch varies from 10 ± 1 ns at 3 kV to 100 ± 50 ns at 500 V

[en] The authors report the development of a miniature laser-triggered high-voltage vacuum switch with a fused KCl and Ni cathode. The switch uses metal-ceramic construction with a sapphire window in the anode to allow the laser beam to strike the cathode surface. Reliable triggering is achieved with only 20 to 40 μJ of laser energy. The switch was operated with a gap voltage ranging from 500 V to 3 kV with switching currents up to 5 kA peak. Switch life greater than one thousand shots without performance degradation has been observed on twenty-five prototype units

[en] The characterization of radioactive hazardous waste, also known as transuranic 'mixed waste' has to be completed before it can be classified for proper treatment (incinerator, mechanical compaction or thermal treatment), packing, and transport. The characterization of the TRU mixed waste is not only complex process but rather an expensive undertaking. The process knowledge is the basic foundation of characterization. It is the documented knowledge of processes and materials that generated the waste. The transuranic waste Quality Assurance Program Plan (QAPP) defines the Data Quality Objectives (DQO's) and provides the scope of analytical parameters and methods required to accurately characterize the radioactive mixed waste. Based on the historical data and process knowledge a sampling and analysis plan can be developed to characterize the radioactive hazardous waste. Based on the characterization, an assessment of the regulatory status can be made before the waste could be accepted for disposal at the WIPP facility. The Waste Acceptance Criteria (WAC) developed by WIPP defines the parameters for receiving and final disposal of the TRU waste. The sets of criteria, such as: heat generated, fissile gram equivalent (FGE), plutonium-equivalent (PE) curies, and specifications of a dose rate have to be met before the waste is accepted for deep geological disposal. The characterization of radioactive waste becomes even more complex due to the presence of iron base metals/alloys, aluminum base metals/alloys, organic, chelating agents that are mixed with plastic, rubber, cellulose, soils and cement. Some of the modern characterization technologies that are under development and currently used for TRU mixed wastes are: nondestructive examination, nondestructive assay, headspace gas analysis, and drum coring for Resources Conservation Recovery Act (RCRA) sampling. (author)

[en] The Waste Isolation Pilot Plant recently completed a project to: upgrade existing safety basis document to be compliant with governing regulations and U.S. Department of Energy standards; integrate multiple documents into a concise set of analyses, controls and commitments; and update key documents supporting the safety basis documents. This paper provides an overview of project activities and provides key lessons learned. (authors)

[en] Oxygen isotope ratios for 40 reservoir rocks from the plutonic basement and overlying andesitic rocks, and 14 separated geothermal quartz samples from the volcanics, range from 2.5 to 9.9 per mil. The lowest δ¹⁸O values (average 2.9 per mil) in diorite cores from wells 401, 407 and 410 are located in the most productive northwest (Mahiao) sector of the field. In the Malitbog sector, the average δ¹⁸O values for basement rocks are higher (c. 4.6 per mil). Plutonic rock samples from the Mamban (well MN1) sector, located outside the present-day field margin, are only slightly altered (6 per mil) except possibly near the contact zone between the basement and overlying volcanics. The highest cumulative fluid/rock ratios are calculated for the Mahiao sector, whereas Malitbog is possibly a relatively recent extension of the field. Relatively shallow (Bao Formation) quartz has δ¹⁸O values suggesting past tectonic uplift