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Rock salt is considered a suitable medium for the permanent disposal of heat‐generating radioactive waste due to its isolation properties. However, excavation damage and heating induce complex and heterogeneous thermal‐hydrological‐mechanical (THM) processes across different zones. Quantifying this heterogeneity is crucial for accurate long‐term performance assessment models, but traditional methods lack the necessary resolution. This study employs 4D electrical resistivity tomography (ERT) monitoring during controlled heating experiments in a salt formation to unravel the spatiotemporal dynamics of THM processes. Advanced time‐lapse inversion and clustering analysis quantify subsurface properties and map the heterogeneity of THM dynamics. The ERT results can estimate subsurface properties and delineate the damaged and intact zones, enabling appropriate parameterization and representation of processes for long‐term modeling. This approach may be used in further improving the predictive models and ensuring the safe long‐term disposal of radioactive waste in rock salt. Plain Language Summary Rock salt is great for the disposal of heat‐generating radioactive waste because it prevents releasing harmful radiation into the environment. However, mining and heating can cause complex changes in temperature, water flow, and pressure, affecting rock salt in various ways. It is important to understand these changes accurately for planning how the disposal will affect the rock salt, but the traditional ways of studying them are not detailed enough. In this study, we used a special technique called 4D ERT while heating up the rock salt to see how these changes happen over time and space. We analyzed the data in advanced ways to measure the underground properties and understand the complex changes. The information can improve how we model and plan the disposal of heat‐generating waste. This new insight makes it easier to ensure that storing heat‐generating radioactive waste in rock salt is safe for a long time. Key Points We employ 4D electrical resistivity tomography (ERT) monitoring during a controlled heating experiment in salt formations The resistivity data exhibits contrasting trends throughout and post‐heating, indicating the heterogeneous thermal‐hydrological‐mechanical processes in rock salt are likely linked to the different levels of excavation damages Employing time‐series clustering technology enables quantification and spatial distributions of excavation damage/disturbed zones within the salt formations which may help further improve the parameterization of long‐term predictive models

Detecting radionuclide gas seepage from clandestine underground nuclear tests is central to nonproliferation explosion monitoring research. Yet, early-time (<6 day) gas transport driven by the explosive pressure wave remains poorly constrained due to scarcity of field data. We simulate multi-phase gas transport in the vadose zone using pre-shot data from a recent chemical explosion in P-Tunnel at the Nevada National Security Site, USA. Despite using a simplified 2D-radial model, predictions of tracer arrival matched observations within one order-of-magnitude. Our results show how transient blast forcing rapidly mobilizes gases from the cavity into surrounding rock – critical for optimizing sensor placement and test planning. This unique integration of field data and modeling represents a significant improvement in our ability to predict gas migration from underground explosions. More broadly, it offers insights into the coupled dynamics of pressure waves and contaminant transport in the vadose zone, with implications for monitoring and hazard assessment.

A recent chemical explosive test in P-Tunnel at the Nevada National Security Site, Nevada, USA, was conducted to better understand how signals propagate from explosions in the subsurface. A primary signal of interest is the migration of gases that can be used to differentiate chemical from nuclear explosions. Gas migration is highly dependent on the rock permeability which is notoriously difficult to determine experimentally in the field due to a potentially large dependence on the scale over which measurements are made. Here, we present pre-explosion permeability estimates to characterize the geologic units surrounding the recent test. Permeability measurements were made at three scales of increasing size: core samples (≈2 cm), borehole packer system tests (≈1 m), and a pre-shot cavity pressurization test (> 10 m) across ten tuff units. Permeability estimates based on core measurements showed little difference from borehole packer tests. However, permeability in most rock units calibrated from cavity pressurization tests resulted in higher permeability estimates by up to two orders of magnitude. Here, we demonstrate that the scale of the measurement significantly impacts the characterization efforts of hydraulic properties in volcanic tuff, and that local-scale measurements (< 10 m scale) do not incorporate enough heterogeneity to accurately predict field-scale flow and mass transport.

An \"insightful\" and in-depth look at anti-science politics and its deadly results (Maria Konnikova, New York Times– bestselling author of The Biggest Bluff ). Thomas Jefferson said, \"Wherever the people are well informed, they can be trusted with their own government.\" But what happens when they aren't? From climate change to vaccinations, transportation to technology, health care to defense, we are in the midst of an unprecedented expansion of scientific progress—and a simultaneous expansion of danger. At the very time we need them most, scientists and the very idea of objective knowledge are being bombarded by a vast, well-funded war on science, and the results are deadly. Whether it's driven by identity politics, ideology, or industry, the result is an unprecedented erosion of thought in Western democracies as voters, policymakers, and justices actively ignore scientific evidence, leaving major policy decisions to be based more on the demands of the most strident voices. This compelling book investigates the historical, social, philosophical, political, and emotional reasons why evidence-based politics are in decline and authoritarian politics are once again on the rise on both left and right—and provides some compelling solutions to bring us to our collective senses, before it's too late. \"If you care about attacks on climate science and the rise of authoritarianism, if you care about biased media coverage and shake-your-head political tomfoolery, this book is for you.\"— The Guardian

Rock salt is considered a suitable medium for the permanent disposal of heat‐generating radioactive waste due to its isolation properties. However, excavation damage and heating induce complex and heterogeneous thermal‐hydrological‐mechanical (THM) processes across different zones. Quantifying this heterogeneity is crucial for accurate long‐term performance assessment models, but traditional methods lack the necessary resolution. This study employs 4D electrical resistivity tomography (ERT) monitoring during controlled heating experiments in a salt formation to unravel the spatiotemporal dynamics of THM processes. Advanced time‐lapse inversion and clustering analysis quantify subsurface properties and map the heterogeneity of THM dynamics. The ERT results can estimate subsurface properties and delineate the damaged and intact zones, enabling appropriate parameterization and representation of processes for long‐term modeling. This approach may be used in further improving the predictive models and ensuring the safe long‐term disposal of radioactive waste in rock salt.

In the US, science has increasingly taken a backstage to politics in policy decisions. But as the country enters the presidential primary season this month, one of the most counterintuitive but effective ways for researchers to make a difference may be to join the GOP.

\"Whenever the people are well informed,\" Thomas Jefferson famously wrote, \"they can be trusted with their own government.\" But what happens when they are not? The United States provide a good illustration: Politicians pass resolutions denying global warming's existence, that astrology can control the weather, and, in some states, even forbid using the words \"Climate Change.\" In every aspect of our society -- from transport to technology, health care to national defense -- we are in the midst of an unprecedented expansion of scientific progress that has led to a simultaneous explosion of real world catastrophe. And yet many western democracies actively ignore how science might help us to survive our own ingenuity. Shawn Lawrence Otto's book investigates the historical, social, and emotional reasons for why this is the case, and offers a vision and an argument to bring us to our collective senses, before it's too late.