Underground Testing of Nuclear Weapons

Underground nuclear tests, though less visually dramatic than atmospheric detonations, harbor significant risks that are often overlooked. The seemingly contained nature of these tests masks the profound and far-reaching impacts on the environment and public health. Over 1,500 underground tests have been conducted. Containment failures were frequent, resulting in the unexpected and uncontrolled release of radiation. Other tests had “controlled” venting of contamination into the atmosphere. Because these tests were considered safer, no notice was given to nearby civilians.

The explosion from the "Sedan" underground nuclear test in Nevada

Consequences

Seismic Activity

Underground nuclear explosions generate substantial seismic waves, akin to natural earthquakes. The immediate and long-term consequences include:

The detonation of nuclear devices underground can trigger seismic events, ranging from minor tremors to significant earthquakes. These induced earthquakes can cause structural damage to buildings and infrastructure, potentially endangering lives.

The explosive force of a nuclear test can cause the land above the detonation site to sink or collapse. This phenomenon, known as subsidence, can create large depressions or craters, posing risks to the environment and human settlements.

The intense pressure from a nuclear explosion can fracture the surrounding rock, leading to the formation of fissures and cracks. These fractures can disrupt the integrity of the earth’s surface, affecting roads, pipelines, and other critical infrastructure.

Radioactive materials released during a nuclear explosion can seep into nearby aquifers. These materials include a variety of radionuclides, such as tritium, cesium-137, and strontium-90, which can persist in the environment for decades.

Contaminated groundwater can enter drinking water supplies, posing severe health risks to local populations. Long-term exposure to radioactive water can lead to increased rates of cancer, genetic mutations, and other serious health issues.

Irrigation systems that rely on groundwater can spread contamination to crops and soil, affecting food safety and agricultural productivity. The accumulation of radionuclides in the food chain can have detrimental effects on both human and animal health.

Groundwater Contamination

One of the most insidious effects of underground nuclear tests is the potential contamination of groundwater.

Long-term Environmental Risks

The repercussions of underground nuclear tests extend far beyond the immediate aftermath, with long-lasting effects on the environment.

Radioactive particles can remain in the soil for many years, continuously emitting radiation. This persistent radiation can render large areas uninhabitable and unusable for agricultural or recreational purposes.

Radiation can disrupt local ecosystems, affecting plant and animal life. Species sensitive to radiation may decline, leading to imbalances in the ecosystem and the potential collapse of certain habitats.

The presence of radioactive materials can alter the chemical composition of the soil, reducing its fertility and productivity. This degradation can have a cascading effect on agricultural output and food security in affected regions.

Preparation Phase

Detonation Phase

Aftermath Phase

Images courtesy of the Federation of American Scientists

Case Study:

The Sedan Test, Project Plowshare

The "Sedan" underground nuclear test crater in Nevada

The Sedan Crater

The Sedan test was a notable US nuclear explosion conducted underground at the Nevada Test Site on July 6, 1962.  The detonation was completed as part of ‘Project Plowshare’ exploring so called ‘peaceful’ nuclear explosions.  The Sedan test was a shallow underground test exploring the use of nuclear weapons for mining.  The fallout and contamination was immense, it is cited as the test which contaminated more U.S. residents than any other.

Key points of Sedan

Crater Formation: The Sedan test created one of the largest man-made craters in the United States, a prominent feature of the Nevada Test Site that significantly altered the landscape.

Radioactive Fallout: The explosion released a substantial amount of radioactive debris into the atmosphere. This fallout was carried by the wind, spreading radioactive contamination over a wide area and impacting downwind populations and ecosystems.

Soil and Groundwater Contamination: The intense heat and radiation from the blast led to long-lasting contamination of the soil and groundwater in the surrounding area. This has had enduring effects on the local environment.

Health Consequences: The radioactive fallout from the Sedan test contributed to increased cancer rates among populations living downwind of the test site. The release of radioactive material posed long-term health risks to both humans and wildlife.

Legacy and Remediation: The Sedan Crater remains a stark reminder of the environmental destruction caused by nuclear tests. Ongoing remediation efforts aim to manage radioactive contamination and monitor the long-term effects on the environment and public health.