Enhanced Performance Assessment System (EPAS) for carbon sequestration.

Sandia National Laboratories performance assessment methodology for long-term environmental programs : the history of nuclear waste management.

“…In addition, as the Yucca Mountain repository program is being terminated, SNL has recently conducted three feasibility and scoping PAs for alternative SNF and HLW disposal approaches: disposal in deep boreholes (Brady, et al 2009); disposal in a clay/shale repository (Hansen, Hardin, et al 2010); and disposal in a granite repository. 10 Finally, SNL has outlined an approach to enhancing and adapting the PA methodology for application in safety analysis of carbon sequestration and storage, with a PA to run both forward and inverse calculations to support optimization of CO 2 injection and real-time site monitoring as an integral part of the system design and operation (Wang, Dewers, et al 2010). This study demonstrated a prototype enhanced PA, and it described an optimization approach that continually fuses monitoring data into the PA model through model inversion and parameter estimation, with model calculations, in turn, turn guiding the design of optimal monitoring and carbon injection.…”

“…The enhanced PA system methodology, shown in Figure 73 (Wang, Dewers, et al 2010, Figure 2), provides PA model able to run both forward and inverse calculations to support optimization of CO 2 injection and real-time site monitoring as an integral part of the system design and operation. The forward model components represent the typical steps of the existing PA methodology, starting with FEPs evaluation, development appropriate computational models for the selected FEPs and scenarios, and then constraining model input parameter values and their uncertainty distributions based on field observations and laboratory experimental data.…”

“…The last example, Figure 11, illustrates a potential adaptation of the SNL PA methodology proposed by Wang, Dewers, et al (2010) to the carbon sequestration in underground reservoirs. This methodology, discussed in Section 8.7, enhances the standard, forward-looking methodology that forecasts long-term behavior of a complex geologic disposal system with realtime monitoring and data analysis, to allow operational changes such as adjusting injection rates of carbon dioxide.…”

“…However, most of the existing modeling effort focused on detailed physical and chemical processes, with little attention to uncertainty quantification of the model predictions, and systematic application of the PA methodology to geologic carbon sequestration systems is still undergoing development, and could benefit from enhanced capabilities. With support provided by the SNL Laboratory Directed Research and Development program, Wang, Dewers, et al (2010) outlined a new methodology for an enhanced PA system, performed a preliminary FEPs analysis for a hypothetical geologic carbon sequestration system, developed a prototype PA model using TOUGH2 and DAKOTA codes, and successfully implemented that system model in a probabilistic analysis based on the Frio pilot injection project near the Texas Gulf Coast, which utilizes the Oligocene Frio Formation as storage reservoir and the overlying Miocene Anahuac Formation as caprock. The enhanced PA model was designed to be generally applicable to geologic carbon sequestration pilot projects currently underway as part of the DOE/National Energy Technology Laboratory partnerships for carbon sequestration (NETL 2011).…”

Nuclear Energy Advanced Modeling and Simulation (NEAMS) waste Integrated Performance and Safety Codes (IPSC) : gap analysis for high fidelity and performance assessment code development.

“…Recommendation 2 -Use DAKOTA to build an enhanced performance assessment system (EPAS): The concept of an EPAS for a radioactive waste disposal system is shown in Figure 12 ( Wang et al, 2010). The forward model components represent the typical steps of the existing PA methodology.…”