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Valdez, Raquel Lynn

Publications and source records attributed to Valdez, Raquel Lynn.

10 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Organizational Resilience in the Context of Information Quality: An Agent-Based Simulation of Structural and Cognitive Influences

This study examines how organizational structure and stress levels affect decision-making with poor quality information. Using an agent-based model, it finds loosely structured organizations are timely but less effective at filtering bad information, while tightly structured ones are slower but better at filtering. The research highlights a trade-off between timeliness and robustness and suggests an optimal stress level for decision-making efficacy.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2023

Critical Role of Water for Energy Transitions Technologies: A Literature Review

This report summarizes the water inputs associated with four technologies playing diverse roles in energy transitions: hydrogen, solar photovoltaics (PV), wind, and batteries. Information in this report is drawn from multiple sources, including peer-reviewed literature, industry and international agency reports, EcoInvent life cycle inventory database, and subject matter expert (SME) consultations. Where possible, insights that characterized water requirements for specific stages of the technology development (e.g., operations, manufacturing, and mining) were prioritized over broader cradle-to-gate assessment values. Furthermore, both direct and indirect water requirements (i.e., associated with associated energy inputs) were considered in this literature review.

08 HYDROGEN↗
DOE OSTI2023

Dynamics of Water, Climate, and Infrastructure

Climate and its impacts on the natural environment, and on the ability of the natural environment to support population and the built environment, stands as a threat multiplier that impacts national and global security. The Water Intersections with Climate Systems Security (WICSS) Strategic Initiative is designed to improve understanding of water’s role in, among other topics, the connection of critical infrastructure to climate in light of competing national and global security interests (including transboundary issues and stability), and identifying research gaps aligned with Sandia, and Federal agency priorities. With this impetus in mind, the WICSS Strategic Initiative team conceptualized a causal loop diagram (CLD) of the relationship between and among climate, the natural environment, population, and the built environment, with an understanding that any such regionally focused system must have externalities that influence the system from beyond its’ control, and metrics for better understanding the consequences of the set of interactions. These are discussed in light of a series of worldviews that focus on portions of the overall systems relationship. The relationships are described and documented in detail. A set of reinforcing and balancing loops are then highlighted within the context of the model. Finally, forward-looking actions are highlighted to describe how this conceptual model can be turned into modeling to address multiple problems described under the purview of the Strategic Initiative.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Assessment of InSAR Seasonal Movements at Bayou Choctaw SPR Site

Ground deformation is important to monitor for the ongoing safety and stability of underground caverns. Implementing InSAR technology to monitor site-wide surface deformation at the Strategic Petroleum Reserve has revealed seasonal ground movements at Bayou Choctaw in Louisiana. The cyclic, seasonal pattern shows soil shrinkage during the spring and summer months and soil expansion during the fall and winter months. Prior to this report, no in-depth investigation was conducted to explain this seasonal phenomenon. However, the ground movement is believed to be near-surface and not geological due to the relatively insignificant movement between years. To better understand seasonality movements, soil properties, land cover, and climatic conditions are assessed to relate near-surface water and soil interactions. The soil, land, and climatic properties all contribute to seasonal ground movement, and vegetation cover and the soil's water capacity contribute to the spatial variability of InSAR seasonal measurements at Bayou Choctaw.

02 PETROLEUM↗
DOE OSTI2021

Cavern Leaching Monitoring CY18 And CY19

The U.S. Strategic Petroleum Reserve (SPR) is a crude oil storage system run by the U.S. Department of Energy (DOE). The reserve consists of 60 active storage caverns spread across four sites in Louisiana and Texas, near the Gulf of Mexico. Beginning in 2016, the SPR began executing U.S. congressionally mandated oil sales. The configuration of the reserve, with a total capacity of greater than 700 MMB, requires raw water to be used instead of saturated brine for oil withdrawals such as for sales. All sales will produce leaching within the caverns used for oil delivery. Thirty-six caverns had a combined total of over 29 MMB of water injected from CY18-CY19 for mandatory sales. Leaching effects were monitored in these caverns to understand how the sales operations may impact the long-term integrity of the caverns. While frequent sonars are the best way to monitor changes in cavern shape, they can be resource intensive for the number of caverns involved in sales and exchanges. An intermediate option is to model the leaching effects and see if any concerning features develop. The leaching effects were modeled here using the Sandia Solution Mining Code (SANSMIC). The results indicate that leaching induced features are not of concern in the majority of the caverns, 32 of 36. Four caverns, BH-107, BH-108, BH-114 and WH-114 have features that may grow with additional leaching and should be monitored as leaching continues in those caverns. Six caverns had post sale sonars which were compared with SANSMIC results. SANSMIC was able to capture the leaching well. A deviation in the SANSMIC and sonar cavern shapes was observed near the cavern floor in caverns with significant floor rise, a process not captured by SANSMIC. These results suggest SANSMIC is a useful tool for monitoring changes in cavern shape due to leaching effects related to sales and exchanges.

02 PETROLEUM↗
DOE OSTI2021

Identification of SPR Caverns with Multiple Oil Layers

This analysis shows that when lower density crude oil is injected into the top of an underground salt storage cavern containing more dense crude, separate oil phases can form and coexist indefinitely. This has been observed at the U.S. Strategic Petroleum Reserve in spite of geothermal heating and natural convection, which tend to mix the contents of containers with significant vertical extent subjected to wall and bottom heating. Such persistent layering can create operational challenges for meeting delivery specifications if high-value, low-vapor pressure oil becomes trapped below incoming low-density, high-vapor pressure oil, effectively blocking access to the lower layers until the top layer is removed. Previous conceptual models assumed that the oil injection process mixed incoming oil with resident oil in a storage cavern, forming a single oil phase with relatively homogeneous properties. Here, a review of historical data from the Strategic Petroleum Reserve revealed that several caverns contain multiple oil layers. As a result, oil layering needs to be another variable considered when planning oil movements at SPR in order to optimize low-vapor pressure oil availability to assist in oil delivery blending.

02 PETROLEUM↗