Scientists agree that even large nuclear explosions have little effect on seismicity outside the area of the blast itself. The largest underground thermonuclear tests conducted by the United States were detonated in Amchitka at the western end of the Aleutian Islands, and the largest of these was the 5 megaton test code-named Cannikin that occurred on November 6, 1971 that did not trigger any earthquakes in the seismically active Aleutian Islands.
On January 19, 1968, a thermonuclear test, code-named Faultless, took place in central Nevada. The code-name turned out to be a poor choice because a fresh fault rupture some 4,000 feet long was produced. Seismograph records showed that the seismic waves produced by the fault movement were much less energetic than those produced directly by the nuclear explosion. Locally, there were some minor earthquakes surrounding the blasts that released small amounts of energy. Scientists looked at the rate of earthquake occurrence in northern California, not far from the test site, at the times of the tests and found nothing to connect the testing with earthquakes in the area.
Generation XTH - Code Hazard, Code Breaker, Code Realize [jap]
Damage in earthquakes depends on the strength of the ground shaking and the ability of a structure to accommodate this shaking. Building codes define the guidelines for how strong structures need to be to perform well in earthquakes and continue to evolve as engineers and scientists better understand earthquakes and how structures respond to ground shaking.
Based on the type of construction and the building code at the time when they were built, we have a pretty good understanding of what buildings are likely to be damaged in future earthquakes. A detailed scientific assessment of the likely damage in a big San Andreas earthquake in southern California (The ShakeOut Earthquake Scenario - A Story That Southern Californians Are Writing) estimated that 300,000 buildings in southern California would be damaged at a moderate level (losing at least 10% the value of the building) as modeled in the M7.8 ShakeOut scenario earthquake. Although this is a large number, it is only 1 out of every 16 buildings in the region. Most buildings will not have significant damage. Moreover, only 1,500 of those buildings will actually collapse. That is less than 1 out of 30,000 buildings in southern California. Widespread collapse of many buildings is not realistic.
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PCBs are not regulated under RCRA, thus do not have a RCRA waste code. EPA does not require boxes 13 and 31 on forms 8700-22 and 8700-22A (if used), respectively, to be completed for shipments only containing PCB waste. However, some States track PCB wastes as State-regulated hazardous wastes, and assign State hazardous waste codes to these wastes. In such a case, the user should follow the State instructions for completing the waste code fields. 2ff7e9595c
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