physics

Nuclear Cratering Group

Nuclear Cratering Group is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Nuclear Cratering Group rather than just read about it. In short: The United States Army Corps of Engineers Nuclear Cratering Group (NCG) was an organization within the U.S. Army Corps of Engineers (USACE), located at the Lawrence Radiation Laboratory, which was involved in research on the potential uses and effects of nuclear devices for large-scale excavation and quarrying.

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Reference excerpt

The United States Army Corps of Engineers Nuclear Cratering Group (NCG) was an organization within the U.S. Army Corps of Engineers (USACE), located at the Lawrence Radiation Laboratory, which was involved in research on the potential uses and effects of nuclear devices for large-scale excavation and quarrying. The group's activities were focused on research for practical applications of nuclear devices, some of which were proposed for the Atomic Energy Commission's (AEC) Project Plowshare program for peaceful nuclear explosions. In particular, the NCG was directed to study excavation techniques for a sea-level canal across the Isthmus of Panama. The Nuclear Cratering Group was established in 1962. It was reorganized as the Explosive Excavation Research Laboratory under the Waterways Experiment Station in 1971.

History The joint USACE/AEC program was established in May 1962 by Presidential directive, with the stated purpose of studying the use of nuclear explosive devices to aid in the construction of harbors, canals, roads, dams, and quarries. In particular, the program was proposed to support research on a new sea-level canal across the Isthmus of Panama or Nicaragua. While the AEC was chiefly responsible for nuclear explosive devices, predictive cratering methods, and execution of actual nuclear explosive tests, the NCG focused on high-explosive testing, nuclear excavation project planning, data compilation on cratering experiments, and engineering studies for the application of nuclear explosives in civil engineering projects. The project's first director was Lieutenant Colonel Ernest Graves Jr. The NCG's initial role was to conduct experiments with non-nuclear explosives, compiling engineering data that could be extrapolated to the design of projects that would employ nuclear explosives, within the framework of Project Plowshare. The NCG was to plan and execute cratering experiments using conventional high explosives as calibration experiments that would lead to means of extrapolating the performance of nuclear explosives, the development of projects that might employ nuclear explosives, and in conjunction with the AEC, to plan and execute experiments using nuclear explosives. The study group was also tasked with a role in the development of military applications for nuclear excavation. Studies examined issues surrounding drilling large-diameter boreholes that could accommodate nuclear devices, and methods of creating a series of craters to form linear excavations. Other work focused on radiological studies to establish safe times for re-entry to new nuclear craters. The Nuclear Cratering Group was reorganized in August 1971 and renamed. The program spent about $175 million, and conducted 22 explosives tests. The U.S. Army Engineer Waterways Experiment Station Explosive Excavation Research Laboratory was its successor activity. Between August 1, 1971, and April 21, 1972, the activity was called the Explosive Excavation Research Office.

Pre-nuclear projects Project Pre-Buggy I and II, Nevada Test Site (NTS), 1962-63 Projects Pre-Schooner I and II, NTS, 1964-65 Projects Pre-Gondola I, II and III, Fort Peck Reservoir, 1966-69 Project Tugboat, Kawaihae, Hawaii, 1969-70 There were a number of smaller projects, mainly involving detonations of small explosive charges in various geological conditions.

Studies Buchanan Dam proposed nuclear quarrying (Project Travois), using a 10 kiloton (kt) device Cochiti Dam, quarrying project under Project Travois. The study was proposed and abandoned in 1966. Twin Springs Dam, proposed quarrying project under Project Travois, using a 20 kt device Project Excavator, proposed high explosive excavation tests in support of Project Travois at Buchanan Dam, Twin Springs damsite, or the Catherine Creek damsite in Oregon, study 1966 -1969. Rampart Dam, proposed nuclear quarrying study. First proposed in 1958 before the NCG was organized, with discussions running until the dam project was abandoned in 1967. Edward Teller was an advocate for nuclear explosives for this project. Whitestone Narrows, Alaska, a study for 1 kt and 10 kt nuclear blasts to widen the navigation channel, proposed in 1964. A study was completed in 1968, which recommended that nuclear excavation not be used. South Point Harbor, proposal for a nuclear cratering project at Ka Lae on the island of Hawaii. Proposed in 1969, and a feasibility study was prepared in 1971. Canal connection between Lake Erie and the Ohio River basin near Warren and Youngstown in Ohio Divide Cut of the Tennessee-Tombigbee Waterway in Mississippi, using 81 devices from 10 to 50 kt, totaling 1.9 Mt Project Phaeton, a proposed one megaton experiment to support Isthmian Canal studies, proposed in 1962. Locations were proposed in several places in Nevada, at Amchitka Island in Alaska, an at Cima Dome in California. Camelsback Dam spillway and quarrying proposal on the Gila River, Arizona. A report in 1969 recommended a 5 Kt nuclear device to excavate the spillway and to provide aggregate for the dam. The dam project was abandoned after a NCG report found geological faulting at the proposed dam location. Chomly Cutoff, a small-boat channel between Cholmondeley Sound and Hetta Inlet near Ketchikan, Alaska Harbor enlargement at Yaquina Bay, Oregon, using nuclear explosives. Young Bay channel, Alaska, proposal for nuclear excavation of a channel at th north end of Admiralty Island. Small boat harbor at Shelter Cove between Fort Bragg and Eureka, California, using a 100 kt device Deep harbor at Kaunakakai, Molokai, Hawaii, 1966, using a 500 kt device Dam in the Bruneau River Canyon, near Boise, Idaho, 19663-1967 Part of Pre-Schooner II. Boca Bypass, railroad cut excavation near Boca, California, study in 1962 Operation Breakup, conventional explosive tests in the ice-covered Blair Lakes near Fairbanks, Alaska. Projects Dogsled and Pre-Dogsled; proposed cratering tests at 11 potential sites in Arizona and Utah, 1963–1964. Project Gondola, nuclear cratering experiment proposed for potential locations in South Dakota, Montana or Nevada., first proposed in 1963 and deferred to 1969–1970, then cancelled. Gondola I yields were to be between 20 Kt and 200 Kt. North Slope Harbor, proposal for the use of nuclear explosives to create an artificial harbor on the North Slope of Alaska for oil transshipment, 1969.

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Worked examples

Example 1 — a first encounter with Nuclear Cratering Group

Start with the simplest possible case. Write down what Nuclear Cratering Group claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Nuclear Cratering Group before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Nuclear Cratering Group ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Nuclear Cratering Group

In research: Nuclear Cratering Group appears in physics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Nuclear Cratering Group in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Nuclear Cratering Group is common in secondary-school and first-year university syllabi. It links to neighbouring topics Lawrence Livermore National Laboratory, Peaceful nuclear explosions, Project Plowshare, so understanding it makes those chapters shorter.
In everyday life: Look for Nuclear Cratering Group outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Nuclear Cratering Group in 20 minutes

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Frequently asked questions

What is Nuclear Cratering Group in simple terms?

Why does Nuclear Cratering Group matter?

Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Nuclear Cratering Group?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Nuclear Cratering Group.