Publications

The U. S. capability to monitor foreign underground nuclear test activities relies heavily on measurement of explosion phenomena, including characteristic seismic, infrasound, radionuclide, and acoustic signals. Despite recent advances in each of these fields, empirical, rather than physics-based, approaches are used to predict and explain observations. Seismologists rely on prior knowledge of the variations of teleseismic and regional seismic parameters such as p- and s-wave arrivals from simple one-dimensional models for the teleseismic case to somewhat more complicated enhanced two-dimensional models for the regional case. Likewise, radionuclide experts rely on empirical results from a handful of limited experiments to determine the radiological source terms present at the surface after an underground test. To make the next step in the advancement of the science of monitoring we need to transform these fields to enable predictive, physics-based modeling and analysis. The Nevada Test Site Source Physics Experiments (N-SPE) provide a unique opportunity to gather precise data from well-designed experiments to improve physics-based modeling capability. In the seismic experiments, data collection will include time domain reflectometry to measure explosive performance and yield, free-field accelerometers, extensive seismic arrays, and infrasound and acoustic measurements. The improved modeling capability that we will develop using this data should enable important advances in our ability to monitor worldwide for nuclear testing. The first of a series of source physics experiments will be conducted in the granite of Climax Stock at the NTS, near the locations of the HARD HAT and PILE DRIVER nuclear tests. This site not only provides a fairly homogeneous and well-documented geology, but also an opportunity to improve our understanding of how fractures, joints, and faults affect seismic wave generation and propagation. The Climax Stock experiments will consist of a 220 lb (TNT equivalent) calibration shot and a 2200 lb (TNT equivalent) over-buried shot conducted in the same emplacement hole. An identical 2200 lb shot at the same location will follow to investigate the effects of pre-conditioning. These experiments also provide an opportunity to advance capabilities for near-field monitoring, and on-site inspections (OSIs) of suspected testing sites. In particular, geologic, physical, and cultural signatures of underground testing can be evaluated using the N-SPE activities as case studies. Furthermore, experiments to measure the migration of radioactive noble gases to the surface from underground explosions will enable development of higher fidelity radiological source term models that can predict migration through a variety of geologic conditions. Because the detection of short-lived radionuclides is essential to determining if an explosion was nuclear or conventional, a better understanding of the gaseous and particulate radionuclide source terms that reach the surface from underground testing is critical to development of OSI capability.

A Remote Monitoring System (RMS) field trial has been conducted with the International Atomic Energy Agency (IAEA) on highly enriched uranium materials in a vault at the Oak Ridge Y-12 Plant. The RMS included a variety of Sandia, Oak Ridge, and Aquila sensor technologies which provide containment seals, video monitoring, radiation asset measurements, and container identification data to the on-site DAS (Data Acquisition System) by way of radio-frequency and Echelon LonWorks networks. The accumulated safeguards information was transmitted to the IAEA via satellite (COMSAT/RSI) and international telephone lines. The technologies tested in the remote monitoring environment are the RadCouple, RadSiP, and SmartShelf sensors from the ORSENS (Oak Ridge Sensors for Enhancing Nuclear Safeguards) technologies; the AIMS (Authenticated Item Monitoring System) motion sensor (AMS), AIMS fiber-optic seal (AFOS), ICAM (Image Compression and Authentication Module) video surveillance system, DAS (Data Acquisition System), and DIRS (Data and Image Review Station) from Sandia; and the AssetLAN identification tag, VACOSS-S seal, and Gemini digital surveillance system from Aquila. The field trial was conducted from October 1996 through May 1997. Tests were conducted during the monthly IAEA Interim Inventory Verification (IIV) inspections for evaluation of the equipment. Experience gained through the field trials will allow the technologies to be applied to various monitoring scenarios.

A remote monitoring system (RMS) field trial will be conducted for the International Atomic Energy Agency (IAEA) on highly enriched uranium materials in a vault at the Oak Ridge Y-12 Plant. Remote monitoring technologies are being evaluated to verify their capability to enhance the effectiveness and timeliness of IAEA safeguards in storage facilities while reducing the costs of inspections and burdens on the operator. Phase one of the field trial, which involved proving the satellite transmission of sensor data and safeguards images from a video camera activated by seals and motion sensors installed in the vault, was completed in September 1995. Phase two involves formal testing of the RMS as a tool for use by the IAEA during their tasks of monitoring the storage of nuclear material. The field trial to be completed during early 1997 includes access and item monitoring of nuclear materials in two storage trays. The RMS includes a variety of Sandia, Oak Ridge, and Aquila sensor technologies that provide video monitoring, radiation attribute measurements, and container identification to the on-site data acquisition system (DAS) by way of radio-frequency and Echelon LONWorks networks. The accumulated safeguards information will be transmitted to the IAEA via satellite (COMSAT/RSI) and international telephone lines.

In the context of U.S. and Russian lab-to-lab initiatives, Sandia National Laboratories contracted with Kurchatov Institute Russian Research Center to demonstrate the feasibility of remotely monitoring the storage of nuclear material. The cooperative experiment was to demonstrate the Remote Monitoring System (RMS) with a minimum of 10 kg of HEU in storage at reciprocal facilities. The Kurchatov Institute selected a site at their facility and the DOE selected a site at the Argonne National Laboratory-West facility. At Kurchatov, there is material for monitoring in a floor vault, a cabinet, and shipping containers. At Argonne West, material stored in two types of storage systems is available for material monitoring. This paper discusses the system concept from both perspectives: the operator of a facility where a RMS is deployed and the user of the RMS at the remote site. The demonstration provides a unique opportunity to have a bilateral demonstration/evaluation where each participant examines all aspects of the system. The hardware and software needed to implement this system is discussed. The impacts to the operation of the facilities are discussed as well as the use of the system to remotely monitor a facility. This technology provides the capability of remotely monitoring the access to the stored nuclear materials but is not a real time security alarm system. Several enhancements to the Remote Monitoring System have been identified for future consideration.