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Nice to meet you, my title is Ling and I completely dig that title. Managing individuals is what I do in my working day occupation. Some time ago he chose to reside in Kansas. One of the things I adore most is greeting card collecting but I don't have the time lately.<br><br>My blog post; [http://Www.evil-Esports.de/cs/index.php?mod=users&action=view&id=5958 Www.evil-Esports.de]
[[File:NTS test preparation4.jpg|thumb|Preparation for an underground nuclear test at the [[Nevada Test Site]] in the 1990s.]]
{{nuclear weapons}}
'''Underground nuclear testing''' refers to [[nuclear testing|test detonations]] of [[nuclear weapon]]s that are performed underground. When the device being tested is buried at sufficient depth, the [[nuclear explosion|explosion]] may be contained, with no release of [[radioactive material]]s to the atmosphere.
 
The extreme heat and pressure of an underground nuclear explosion causes changes in the surrounding [[rock (geology)|rock]]. The rock closest to the location of the test is vaporised, forming a cavity. Farther away, there are zones of crushed, cracked, and irreversibly strained rock. Following the explosion, the rock above the cavity may collapse, forming a rubble chimney. If this chimney reaches the surface, a bowl-shaped [[subsidence crater]] may form.
 
The first underground test took place in 1951; further tests provided information that eventually led to the signing of the [[Partial Test Ban Treaty|Limited Test Ban Treaty]] in 1963, which banned all nuclear tests except for those performed underground. From then until the signing of the [[Comprehensive Test Ban Treaty]] in 1996, most nuclear tests were performed underground, in order to prevent [[nuclear fallout]] from entering into the atmosphere.
 
==Background==
 
Although public concern about fallout from nuclear testing grew in the early 1950s,<ref name="ctbto">{{cite web |publisher=The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization |title=History of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) |url=http://www.ctbto.org/treaty/history.html}}</ref><ref name="ortmeyer1997">{{cite journal |url=http://books.google.com/?id=vgwAAAAAMBAJ&pg=PA46 |first=Pat |last=Ortmeyer |coauthors=Makhijani, Arjun |date=November–December 1997 |title= Worse Than We Know |journal=[http://thebulletin.org ''Bulletin of the Atomic Scientists'']}}</ref> fallout was discovered after the [[Trinity Test|Trinity]] test in 1945.<ref name="ortmeyer1997" /> Photographic film manufacturers would later report 'fogged' films, these were traced both to ''Trinity'' and later tests at the [[Nevada Test Site]].<ref name="ortmeyer1997" /> Intense fallout from the 1953 ''[[Upshot-Knothole Simon|Simon]]'' test was documented as far as Albany, New York.<ref name="ortmeyer1997" />
 
The fallout from the March 1954 ''[[Castle Bravo|Bravo]]'' test in the [[Pacific Ocean|Pacific]] would have "scientific, political and social implications that have continued for more than 40 years."<ref name="eisenbud1997">{{cite journal |title=Monitoring distant fallout: The role of the Atomic Energy Commission Health and Safety Laboratory during the Pacific tests, with special attention to the events following Bravo |first=Merril |last=Eisenbud |journal=Health Physics |date=July 1997 |volume=73 |issue=1 |url=http://www.eh.doe.gov/health/marshall/marsh/journal/rpt-2.pdf |format= &ndash; <sup>[http://scholar.google.co.uk/scholar?hl=en&lr=&q=author%3A+intitle%3AMonitoring+distant+fallout%3A+The+role+of+the+Atomic+Energy+Commission+Health+and+Safety+Laboratory+during+the+Pacific+tests%2C+with+special+attention+to+the+events+following+Bravo&as_publication=Health+Physics&as_ylo=1997&as_yhi=1997&btnG=Search Scholar search]</sup>}} {{Dead link|date=June 2008}}</ref> The multi-megaton test caused fallout to occur on the islands of Rongerik and Rongelap, and a [[Japan]]ese fishing boat known as the ''[[Daigo Fukuryū Maru]]'' (Lucky Dragon).<ref name="eisenbud1997" /> Prior to this test, there was "insufficient" appreciation of the dangers of fallout.<ref name="eisenbud1997" />
 
The test became an international incident. In a PBS interview, the historian Martha Smith argued: "In Japan, it becomes a huge issue in terms of not just the government and its protest against the United States, but all different groups and all different peoples in Japan start to protest. It becomes a big issue in the media. There are all kinds of letters and protests that come from, not surprisingly, Japanese fishermen, the fishermen's wives; there are student groups, all different types of people; that protest against the Americans' use of the Pacific for nuclear testing. They're very concerned about, first of all, why the United States even has the right to be carrying out those kinds of tests in the Pacific. They're also concerned about the health and environmental impact."<ref name="pbs_smith">{{cite web |title=Martha Smith on: The Impact of the Bravo Test |publisher=Public Broadcasting Service |url=http://www.pbs.org/wgbh/amex/bomb/filmmore/reference/interview/marthasmith01.html}}</ref> The Prime Minister of India "voiced the heightened international concern" when he called for the elimination of all nuclear testing worldwide.<ref name="ctbto" />
 
Knowledge about fallout and its effects grew, and with it concern about the global environment and long-term genetic damage.<ref name="state_ltbt">{{cite web |title=Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water |publisher=US Department of State |url=http://www.state.gov/t/ac/trt/4797.htm}}</ref> Talks between the United States, the United Kingdom, Canada, France, and the Soviet Union began in May 1955 on the subject of an international agreement to end nuclear tests.<ref name="state_ltbt" /> On August 5, 1963, representatives of the [[United States]], the [[Soviet Union]], and the [[United Kingdom]] signed the Limited Test Ban Treaty, forbidding testing of nuclear weapons in the atmosphere, in space, and underwater.<ref name="jfklibrary">{{cite web |title=JFK in History: Nuclear Test Ban Treaty |url=http://www.jfklibrary.org/Historical+Resources/JFK+in+History/Nuclear+Test+Ban+Treaty.htm |publisher=John F. Kennedy Presidential Library and Museum}}</ref> Agreement was facilitated by the decision to allow underground testing, eliminating the need for on-site inspections that concerned the Soviets.<ref name="jfklibrary"/> Underground testing was allowed, provided that it does not cause "radioactive debris to be present outside the territorial limits of the State under whose jurisdiction or control such explosion is conducted."<ref name="state_ltbt" />
 
==Early history of underground testing==
{{Globalize/US|date=December 2010}}
Following analysis of underwater detonations that were part of [[Operation Crossroads]] in 1946, inquiries were made regarding the possible military value of an underground explosion.<ref name="gladeck1986">{{cite book |title=For the Record - A History of the Nuclear Test Personnel Review Program, 1978-1986 (DNA 601F) |publisher=Defense Nuclear Agency |first=F |last=Gladeck |coauthors=Johnson A. |year=1986 |url=http://handle.dtic.mil/100.2/ADA306360}}</ref> The [[Joint Chiefs of Staff]] thus obtained the agreement of the [[United States Atomic Energy Commission|Atomic Energy Commission]] to perform experiments on both surface and sub-surface detonations.<ref name="gladeck1986" /> The island of [[Amchitka]] was initially selected for these tests in 1950, but the site was later deemed unsuitable and the tests were moved to the [[Nevada Test Site]].<ref name="doe_responsib">{{cite web |url=http://www.osti.gov/bridge/servlets/purl/758922-sfDXiQ/webviewable/758922.pdf |title=Amchitka Island, Alaska: Potential U.S. Department of Energy site responsibilities (DOE/NV-526) |date=December 1998 |publisher=Department of Energy |accessdate=2006-10-09}}</ref>
 
[[File:UncleNuclearTest1951.jpg|thumb|right|''Buster-Jangle Uncle'', the first underground nuclear explosion.]]
The first underground nuclear test was conducted on 29 November 1951.<ref name="tecsoc">{{cite web |title=Today in Technology History: November 29 |publisher=The Center for the Study of Technology and Society |url=http://www.tecsoc.org/pubs/history/2001/nov29.htm}}</ref><ref name="adushkin2001">{{cite web |title=USGS Open File Report 01-312: Containment of Soviet underground nuclear explosions |first=Vitaly V. |last=Adushkin |coauthors=Leith, William |publisher=US Department of the Interior Geological Survey |date=September 2001 |url=http://geology.er.usgs.gov/eespteam/pdf/USGSOFR01312.pdf}}</ref><ref>Some sources identify later tests as the "first." Adushkin (2001) defines such a test as "the near-simultaneous detonation of one or more nuclear charges inside one underground excavation (a tunnel, shaft or borehole)", and identifies ''Uncle'' as the first.</ref> This was the 1.2 [[kiloton]] ''[[Operation Buster-Jangle|Buster-Jangle Uncle]]'',<ref>Some sources refer to the test as ''Jangle Uncle'' (e.g., Adushkin, 2001) or ''Project Windstorm'' (e.g., DOE/NV-526, 1998). Operation ''Buster'' and Operation ''Jangle'' were initially conceived as separate operations, and ''Jangle'' was at first known as ''Windstorm'', but the AEC merged the plans into a single operation on 19 June 1951. See Gladeck, 1986.</ref> which detonated 5.2&nbsp;m (17&nbsp;ft) beneath ground level.<ref name="adushkin2001" /> The test was designed as a scaled-down investigation of the effects of a 23 kiloton ground penetrating [[Gun-type fission weapon|gun-type]] device that was then being considered for use as a cratering and [[bunker buster|bunker-buster]] weapon.<ref name="nwa_bj">{{cite web |title=Operation Buster-Jangle |publisher=The Nuclear Weapons Archive |url=http://nuclearweaponarchive.org/Usa/Tests/Busterj.html}}</ref> The explosion resulted in a cloud that rose to 11,500&nbsp;ft, and deposited fallout to the north and north-northeast.<ref name="dna_6025f">{{cite book |title=Shots Sugar and Uncle: The final tests of the Buster-Jangle series (DNA 6025F) |first=Jean |last=Ponton |coauthors=''et al.'' |date=June 1982 |publisher=Defense Nuclear Agency |url=http://www.dtra.mil/rd/programs/nuclear_personnel/docs%5CT24299.PDF}}</ref> The resulting crater was 260 feet wide and 53 feet deep.<ref name="nwa_bj" />
 
[[File:Operation Teapot - Ess.jpg|thumb|''Teapot Ess''.]]
The next underground test was ''Teapot Ess'', on 23 March 1955.<ref name="adushkin2001" /> The 1 kiloton explosion was an operational test of an [[Atomic Demolition Munition|atomic demolition munition]] (ADM).<ref name="ponton1981">{{cite book |title=Shots Ess through Met and Shot Zucchini: The final Teapot tests (DNA 6013F) |date=November 1981 |first=Jean |last=Ponton |coauthors=''et al.'' |publisher=Defense Nuclear Agency |url=http://www.dtra.mil/rd/programs/nuclear_personnel/docs%5CT8592.PDF}}</ref> It was detonated 67 feet underground, in a shaft lined with corrugated steel, which was then back-filled with sandbags and dirt.<ref name="nwa_tp">{{cite web |title=Operation Teapot |publisher=The Nuclear Weapons Archive |url=http://nuclearweaponarchive.org/Usa/Tests/Teapot.html}}</ref> Because the ADM was buried underground, the explosion blew tons of earth upwards,<ref name="ponton1981" /> creating a crater 300 feet wide and 128 feet deep.<ref name="nwa_tp" /> The resulting [[mushroom cloud]] rose to a height of 12,000 feet and subsequent [[radioactive fallout]] drifted in an easterly direction, travelling as far as {{convert|225|km|mi|abbr=on}} from ground zero.<ref name="ponton1981" />
 
On 26 July 1957, ''[[Operation Plumbbob|Plumbbob]] Pascal-A'' was detonated at the bottom of a 485-foot shaft.<ref name="nwa_pb">{{cite web |title=Operation Plumbbob |publisher=The Nuclear Weapons Archive |url=http://nuclearweaponarchive.org/Usa/Tests/Plumbob.html}}</ref><ref>According to the Nuclear Weapons Archive, the yield is described as "slight", but was approximately 55 tons.</ref> According to one description, it "ushered in the era of underground testing with a magnificent pyrotechnic [[Roman candle (firework)|Roman candle]]!"<ref name="campbell1983">{{cite journal |title=Field Testing: The Physical Proof of Design Principles |first=Bob |last=Campbell |coauthors=''et al.'' |journal=Los Alamos Science |year=1983 |url=http://www.fas.org/sgp/othergov/doe/lanl/pubs/00285892.pdf}}</ref> As compared with an above-ground test, the radioactive debris released to the atmosphere was reduced by a factor of ten.<ref name="campbell1983" /> Theoretical work began on possible containment schemes.<ref name="campbell1983" />
 
[[File:Plumbbob Rainier 001.jpg|thumb|Dust raised by ''Plumbbob Rainier''.]]
[[File:Plumbbob Rainier 011.jpg|thumb|Layout of the ''Plumbbob Rainier'' tunnel.]]
''Plumbbob Rainier'' was detonated at 899&nbsp;ft underground on 19 September 1957.<ref name="nwa_pb" /> The 1.7 kt explosion was the first to be entirely contained underground, producing no fallout.<ref name="doe_0800021_22">{{cite web |title=Operation Plumbbob |publisher=Department of Energy |url=http://www.nv.doe.gov/library/films/fulltext/0800021_22.htm}}</ref> The test took place in a 1,600<ref>{{cite book |title=ORAU Team: NIOSH Dose Reconstruction Project |first=Gene |last=Rollins |year=2004 |publisher=Centers for Disease Control |url=http://www.cdc.gov/niosh/ocas/pdfs/tbd/nts4.pdf}}
</ref> &ndash; 2,000&nbsp;ft<ref name="lanl_pb">{{cite web |title=Plumbbob Photographs |publisher=Los Alamos National Laboratory |url=http://www.lanl.gov/orgs/esa/esa-wr/documents/nts_cdrom4.pdf}}</ref> horizontal tunnel in the shape of a hook.<ref name="lanl_pb" /> The hook "was designed so explosive force will seal off the non-curved portion of tunnel nearest the detonation before gases and fission fragments can be vented around the curve of the tunnel's hook."<ref name="lanl_pb" /> This test would become the prototype for larger, more powerful tests.<ref name="doe_0800021_22" /> Rainier was announced in advance, so that seismic stations could attempt to record a signal.<ref name="llnl_50s">{{cite web |title=Accomplishments in the 1950s |publisher=Lawrence Livermore National Laboratory |url=http://www.llnl.gov/50th_anniv/decades/1950s.htm}}</ref> Analysis of samples collected after the test enabled scientists to develop an understanding of underground explosions that "persists essentially unaltered today."<ref name="llnl_50s" /> The information would later provide a basis for subsequent decisions to agree to the Limited Test Ban Treaty.<ref name="llnl_50s" />
 
''Cannikin'', the last test at the [[Amchitka]] facility was detonated on 6 November 1971.  At approximately 5 [[TNT equivalent|megatons]], it was the largest underground test in US history.<ref>{{cite web |url=http://www.greenpeace.org/raw/content/usa/press/reports/nuclear-flashback.pdf
|first=Pam |last=Miller |title=Nuclear Flashback: Report of a Greenpeace Scientific Expedition to Amchitka Island, Alaska – Site of the Largest Underground Nuclear Test in U.S. History |accessdate=2006-10-09 |archiveurl = http://web.archive.org/web/20060928190111/http://www.greenpeace.org/raw/content/usa/press/reports/nuclear-flashback.pdf |archivedate = September 28, 2006}}</ref>
 
== Effects ==
[[File:Nuclear explosion craters schema 1.png|thumb|Relative crater sizes and shapes resulting from various burst depths.]]
The effects of an underground nuclear test may vary according to factors including the depth and yield of the explosion, as well as the nature of the surrounding rock.<ref name="McEwan"/> If the test is conducted at sufficient depth, the test is said to be ''contained'', with no venting of gases or other contaminants to the environment.<ref name="McEwan"/> In contrast, if the device is buried at insufficient depth ("underburied"), then rock may be expelled by the explosion, forming a [[Subsidence crater|crater]] surrounded by [[ejecta]], and releasing high-pressure gases to the atmosphere (the resulting crater is usually conical in profile, circular, and may range between tens to hundreds of metres in diameter and depth<ref name="Hawkins"/>). One figure used in determining how deeply the device should be buried is the ''scaled depth of burial'', or ''-burst''.<ref name="McEwan"/> This figure is calculated as the burial depth in metres divided by the [[cube root]] of the yield in kilotons. It is estimated that, in order to ensure containment, this figure should be greater than 100.<ref name="McEwan"/><ref>Hawkins and Wohletz specify a figure of 90-125.</ref>
 
{| border="1" cellpadding="5" cellspacing="0" style="margin: 1em 2em 1em 0; float:left"
|+ '''Zones in surrounding rock'''
|-
! style="background:#efefef;" | Name
! style="background:#ffdead;" | Radius<ref name="Hawkins"/>
|-
| Melt cavity || 4 &ndash; 12 m/kt<sup>1/3</sup>
|-
| Crushed zone || 30 – 40 m/kt<sup>1/3</sup>
|-
| Cracked zone || 80 – 120 m/kt<sup>1/3</sup>
|-
| Zone of irreversible strain || 800 – 1100 m/kt<sup>1/3</sup>
|}
 
The energy of the nuclear explosion is released in one [[microsecond]]. In the following few microseconds, the test hardware and surrounding rock are vaporised, with temperatures of several million degrees and pressures of several million atmospheres.<ref name="McEwan">{{cite book | last=McEwan | first=A. C. | chapter=Environmental effects of underground nuclear explosions | editor=Goldblat, Jozef; Cox, David | title=Nuclear Weapon Tests: Prohibition Or Limitation? | year=1988 | publisher=Oxford University Press | isbn=0-19-829120-5 | pages=75–79}}</ref> Within milliseconds, a bubble of high-pressure gas and [[steam]] is formed. The heat and expanding shock wave cause the surrounding rock to vaporise, or be melted further away, creating a ''melt cavity''.<ref name="Hawkins"/> The shock-induced motion and high internal pressure cause this cavity to expand outwards, which continues over several tenths of a second until the pressure has fallen sufficiently, to a level roughly comparable with the weight of the rock above, and can no longer grow.<ref name="Hawkins"/> Although not observed in every explosion, four distinct zones (including the melt cavity) have been described in the surrounding rock. The ''crushed zone'', about two times the radius of the cavity, consists of rock that has lost all of its former integrity. The ''cracked zone'', about three times the cavity radius, consists of rock with radial and concentric fissures. Finally, the ''zone of irreversible strain'' consists of rock deformed by the pressure.<ref name="Hawkins">{{cite web | last=Hawkins | first=Wohletz | title=Visual Inspection for CTBT Verification | year=1996 | publisher=Los Alamos National Laboratory |url=http://www.ees1.lanl.gov/Wohletz/LAMS-13244-MS.pdf}}</ref> The following layer undergoes only an [[elastic deformation]]; the strain and subsequent release then forms a [[seismic wave]]. A few seconds later the molten rock starts collecting on the bottom of the cavity and the cavity content begins cooling. The rebound after the shock wave causes compressive forces to build up around the cavity, called a '''stress containment cage''', sealing the cracks.<ref name="undcont">[http://www.princeton.edu/~ota/disk1/1989/8909/8909.PDF The Containment of Underground Nuclear Explosions]. (PDF) . Retrieved on 2010-02-08.</ref>
 
Several minutes to days later, once the heat dissipates enough, the steam condenses, and the pressure in the cavity falls below the level needed to support the overburden, the rock above the void falls into the cavity, creating a ''[[rubble chimney]]''. Depending on various factors, including the yield and characteristics of the burial, this collapse may extend to the surface. If it does, a [[subsidence crater]] is created.<ref name="Hawkins"/> Such a crater is usually bowl-shaped, and ranges in size from a few tens of metres to over a kilometre in diameter.<ref name="Hawkins"/> At the [[Nevada Test Site]], 95 percent of tests conducted at a scaled depth of burial (SDOB) of less than 150 caused surface collapse, compared with about half of tests conducted at a SDOB of less than 180.<ref name="Hawkins"/> The radius ''r'' (in feet) of the cavity is proportional to the [[cube root]] of the yield ''y'' (in kilotons), ''r'' = 55 * <math>\sqrt[3]{y}</math>; a 8 kiloton explosion will create a cavity with radius of 110 feet.<ref name="undcont" />
 
[[File:Whetstone Sulky 001.jpg|thumb|Rubble mound formed by ''Whetstone Sulky''.]]
Other surface features may include disturbed ground, [[pressure ridge (lava)|pressure ridge]]s, [[fault (geology)|faults]], water movement (including changes to the [[water table]] level), [[rockfall]]s, and ground slump.<ref name="Hawkins" /> Most of the gas in the cavity is composed of steam; its volume decreases dramatically as the temperature falls and the steam condenses. There are however other gases, mostly [[carbon dioxide]] and [[hydrogen]], which do not condense and remain gaseous. The carbon dioxide is produced by thermal decomposition of [[carbonate]]s, hydrogen is created by reaction of [[iron]] and other metals from the nuclear device and surrounding equipment. The amount of carbonates and water in the soil and the available iron have to be considered in evaluating the test site containment; water-saturated [[clay]] soils may cause structural collapse and venting. Hard basement rock may reflect shock waves of the explosion, also possibly causing structural weakening and venting. The noncondensible gases may stay absorbed in the pores in the soil. Large amount of such gases can however maintain enough pressure to drive the fission products to the ground.<ref name="undcont" />
 
[[File:Operation Emery - Baneberry.jpg|thumb|Radioactivity release during ''Baneberry''.]]
Escape of radioactivity from the cavity is known as '''containment failure'''. Massive, prompt, uncontrolled releases of fission products, driven by the pressure of steam or gas, are known as '''venting'''; an example of such failure is the [[Yucca Flat#Baneberry|Baneberry]] test. Slow, low-pressure uncontrolled releases of radioactivity are known as '''seeps'''; these have little to no energy are not visible and have to be detected by instruments. '''Late-time seeps''' are releases of noncondensable gases days or weeks after the blast, by diffusion through pores and crack, probably assisted by a decrease of atmospheric pressure (so called ''atmospheric pumping''). When the test tunnel has to be accessed, '''controlled tunnel purging''' is performed; the gases are filtered, diluted by air and released to atmosphere when the winds will disperse them over sparsely populated areas. Small activity leaks resulting from operational aspects of tests are called '''operational releases'''; they may occur e.g. during drilling into the explosion location during [[core sampling]], or during the sampling of explosion gases. The radionuclide composition differs by the type of releases; large prompt venting releases significant fraction (up to 10%) of fission products, while late-time seeps contain only the most volatile gases. Soil absorbs the reactive chemical compounds, so the only nuclides filtered through soil into the atmosphere are the noble gases, primarily [[krypton]]-85 and [[xenon]]-133.<ref name="undcont" />
 
The released nuclides can undergo [[bioaccumulation]]. Iodine-131, strontium-90 and caesium-137 are concentrated in milk of grazing cows; cow milk is therefore a convenient, sensitive fallout indicator. Soft tissues of animals can be analyzed for gamma emitters, bones and liver for strontium and plutonium, and blood, urine and soft tissues are analyzed for tritium.<ref name="undcont" />
 
Although there were early concerns about [[earthquake]]s arising as a result of underground tests, there is no evidence that this has occurred.<ref name="McEwan"/> However, fault movements and ground fractures have been reported, and explosions often precede a series of [[aftershock]]s, thought to be a result of cavity collapse and chimney formation. In a few cases, seismic energy released by fault movements has exceeded that of the explosion itself.<ref name="McEwan"/>
 
==International treaties==
Signed in Moscow on August 5, 1963 by representatives of the United States, the Soviet Union, and the United Kingdom, the Limited Test Ban Treaty agreed to ban nuclear testing in the atmosphere, in space, and underwater.<ref name="jfklibrary" /> Due to the Soviet government's concern about the need for the on-site inspections, underground tests were excluded from the ban.<ref name="jfklibrary" /> 108 countries would eventually sign the treaty, with the significant exception of China.<ref name="gwu" >{{cite web |title=The Making of the Limited Test Ban Treaty, 1958-1963 |url=http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB94/ |publisher=The George Washington University}}</ref>
 
In 1974, the United States and the Soviet Union signed the [[Threshold Test Ban Treaty]], which banned underground tests with yields greater than 150 kilotons.<ref name="nas" >{{cite book |author=National Academy of Sciences |title=Technical Issues Related to the Comprehensive Nuclear Test Ban Treaty |year=2002 |publisher=National Academies |isbn=0-309-08506-3}}</ref> By the 1990s, technologies to monitor and detect underground tests had matured to the point that tests of one kiloton or over could be detected with high probability, and in 1996 negotiations began under the auspices of the [[United Nations]] to develop a comprehensive test ban.<ref name="gwu" /> The resulting [[Comprehensive Nuclear-Test-Ban Treaty]] was signed in 1996 by the United States, Russia, United Kingdom, France, and China.<ref name="gwu" /> However, following the United States Senate decision not to ratify the treaty in 1999, it is still yet to be ratified by 8 of the required 44 'Annex 2' states and so has not entered into force as United Nations law.
 
===Monitoring===
 
In the late 1940s, the United States began to develop the capability to detect atmospheric testing using air sampling; this system was able to detect the first Soviet test in 1949.<ref name="nas"/> Over the next decade, this system was improved, and network of seismic monitoring stations was established to detect underground tests.<ref name="nas"/> Development of the Threshold Test Ban Treaty in the mid-1970s led to an improved understanding of the relationship between test yield and resulting seismic magnitude.<ref name="nas"/>
 
When negotiations began in the mid-1990s to develop a comprehensive test ban, the international community was reluctant to rely upon the detection capabilities of individual [[List of states with nuclear weapons|nuclear weapons states]] (especially the United States), and instead wanted an international detection system.<ref name="nas"/> The resulting International Monitoring System consists of a network of a total of 321 monitoring stations and 16 radionuclide laboratories.<ref name="ctbtover">{{cite web |title=An Overview of the Verification Regime |url=http://www.ctbto.org/verification/overview.html |publisher=Comprehensive Nuclear-Test-Ban Treaty Organization}}</ref> Fifty "primary" seismic stations send data continuously to the International Data Center, along with 120 "auxiliary" stations which send data on request. The resulting data is used to locate the [[Epicenter|epicentre]], and distinguish between the seismic signatures of an underground nuclear explosion and an earthquake.<ref name="nas"/><ref>{{cite web |title=Verification Technologies: Seismology |url=http://www.ctbto.org/verification/seismology.html |publisher=Comprehensive Nuclear-Test-Ban Treaty Organization}}</ref> Additionally, eighty radionuclide stations detect radioactive particles vented by underground explosions. Certain radionuclides constitute clear evidence of nuclear tests; the presence of noble gases can indicate whether an underground explosion has taken place.<ref>{{cite web |title=Verification Technologies: Radionuclide |url=http://www.ctbto.org/verification/radionuclide.html |publisher=Comprehensive Nuclear-Test-Ban Treaty Organization}}</ref> Finally, eleven hydroacoustic stations<ref>{{cite web |title=Verification Technologies: Hydroacoustics |url=http://www.ctbto.org/verification/hydroacoustics.html |publisher=Comprehensive Nuclear-Test-Ban Treaty Organization}}</ref> and sixty infrasound stations<ref>{{cite web |title=Verification Technologies: Infrasound |url=http://www.ctbto.org/verification/infrasound.html |publisher=Comprehensive Nuclear-Test-Ban Treaty Organization}}</ref> monitor underwater and atmospheric tests.
 
== See also ==
* [[Subsidence crater]]
 
==Notes and references==
{{Reflist|2}}
 
==External links==
 
<!-- TODO: use as refs instead -->
*http://www.princeton.edu/~globsec/publications/pdf/3_3-4Adushkin.pdf
*[http://thebulletin.metapress.com/content/k863mt6800685p0x/?p=76f6d23b4b71493fbbdef7245e96ae47&pi=16 Nuclear Pursuits], [http://thebulletin.org ''The Bulletin of the Atomic Scientists], September/October 2003
*http://www.unscear.org/unscear/en/publications.html
*http://www.ingv.it/~roma/SITOINGLESE/research_projects/CTBTO/explosions.html
*http://www.globalsecurity.org/wmd/intro/ugt.htm
*http://www.fas.org/nuke/intro/nuke/ugt-nts.htm
*http://www.lanl.gov/natlsecurity/nuclear/current/subcritical.shtml
*http://www.atomictraveler.com/UndergroundTestOTA.pdf
*http://www-pub.iaea.org/MTCD/publications/PDF/Pub1215_web.pdf
*''The Soviet Program for Peaceful Uses of Nuclear Explosions'', M. D. Nordyke, [http://www.osti.gov/bridge/product.biblio.jsp?osti_id=793554 UCRL-ID-12441O Rev 2]
*http://www.princeton.edu/~globsec/publications/effects/effects.shtml
 
<!-- 2000 report, annex c, table 22 particularly useful, as well as 1993, p91-120. also research Brownlee, Robert -->
 
{{Nuclear Technology}}
 
{{DEFAULTSORT:Underground Nuclear Testing}}
[[Category:Nuclear warfare]]
[[Category:Underground nuclear explosive tests]]

Revision as of 17:16, 18 December 2013

Preparation for an underground nuclear test at the Nevada Test Site in the 1990s.

Template:Nuclear weapons Underground nuclear testing refers to test detonations of nuclear weapons that are performed underground. When the device being tested is buried at sufficient depth, the explosion may be contained, with no release of radioactive materials to the atmosphere.

The extreme heat and pressure of an underground nuclear explosion causes changes in the surrounding rock. The rock closest to the location of the test is vaporised, forming a cavity. Farther away, there are zones of crushed, cracked, and irreversibly strained rock. Following the explosion, the rock above the cavity may collapse, forming a rubble chimney. If this chimney reaches the surface, a bowl-shaped subsidence crater may form.

The first underground test took place in 1951; further tests provided information that eventually led to the signing of the Limited Test Ban Treaty in 1963, which banned all nuclear tests except for those performed underground. From then until the signing of the Comprehensive Test Ban Treaty in 1996, most nuclear tests were performed underground, in order to prevent nuclear fallout from entering into the atmosphere.

Background

Although public concern about fallout from nuclear testing grew in the early 1950s,[1][2] fallout was discovered after the Trinity test in 1945.[2] Photographic film manufacturers would later report 'fogged' films, these were traced both to Trinity and later tests at the Nevada Test Site.[2] Intense fallout from the 1953 Simon test was documented as far as Albany, New York.[2]

The fallout from the March 1954 Bravo test in the Pacific would have "scientific, political and social implications that have continued for more than 40 years."[3] The multi-megaton test caused fallout to occur on the islands of Rongerik and Rongelap, and a Japanese fishing boat known as the Daigo Fukuryū Maru (Lucky Dragon).[3] Prior to this test, there was "insufficient" appreciation of the dangers of fallout.[3]

The test became an international incident. In a PBS interview, the historian Martha Smith argued: "In Japan, it becomes a huge issue in terms of not just the government and its protest against the United States, but all different groups and all different peoples in Japan start to protest. It becomes a big issue in the media. There are all kinds of letters and protests that come from, not surprisingly, Japanese fishermen, the fishermen's wives; there are student groups, all different types of people; that protest against the Americans' use of the Pacific for nuclear testing. They're very concerned about, first of all, why the United States even has the right to be carrying out those kinds of tests in the Pacific. They're also concerned about the health and environmental impact."[4] The Prime Minister of India "voiced the heightened international concern" when he called for the elimination of all nuclear testing worldwide.[1]

Knowledge about fallout and its effects grew, and with it concern about the global environment and long-term genetic damage.[5] Talks between the United States, the United Kingdom, Canada, France, and the Soviet Union began in May 1955 on the subject of an international agreement to end nuclear tests.[5] On August 5, 1963, representatives of the United States, the Soviet Union, and the United Kingdom signed the Limited Test Ban Treaty, forbidding testing of nuclear weapons in the atmosphere, in space, and underwater.[6] Agreement was facilitated by the decision to allow underground testing, eliminating the need for on-site inspections that concerned the Soviets.[6] Underground testing was allowed, provided that it does not cause "radioactive debris to be present outside the territorial limits of the State under whose jurisdiction or control such explosion is conducted."[5]

Early history of underground testing

Template:Globalize/US Following analysis of underwater detonations that were part of Operation Crossroads in 1946, inquiries were made regarding the possible military value of an underground explosion.[7] The Joint Chiefs of Staff thus obtained the agreement of the Atomic Energy Commission to perform experiments on both surface and sub-surface detonations.[7] The island of Amchitka was initially selected for these tests in 1950, but the site was later deemed unsuitable and the tests were moved to the Nevada Test Site.[8]

Buster-Jangle Uncle, the first underground nuclear explosion.

The first underground nuclear test was conducted on 29 November 1951.[9][10][11] This was the 1.2 kiloton Buster-Jangle Uncle,[12] which detonated 5.2 m (17 ft) beneath ground level.[10] The test was designed as a scaled-down investigation of the effects of a 23 kiloton ground penetrating gun-type device that was then being considered for use as a cratering and bunker-buster weapon.[13] The explosion resulted in a cloud that rose to 11,500 ft, and deposited fallout to the north and north-northeast.[14] The resulting crater was 260 feet wide and 53 feet deep.[13]

Teapot Ess.

The next underground test was Teapot Ess, on 23 March 1955.[10] The 1 kiloton explosion was an operational test of an atomic demolition munition (ADM).[15] It was detonated 67 feet underground, in a shaft lined with corrugated steel, which was then back-filled with sandbags and dirt.[16] Because the ADM was buried underground, the explosion blew tons of earth upwards,[15] creating a crater 300 feet wide and 128 feet deep.[16] The resulting mushroom cloud rose to a height of 12,000 feet and subsequent radioactive fallout drifted in an easterly direction, travelling as far as Template:Convert from ground zero.[15]

On 26 July 1957, Plumbbob Pascal-A was detonated at the bottom of a 485-foot shaft.[17][18] According to one description, it "ushered in the era of underground testing with a magnificent pyrotechnic Roman candle!"[19] As compared with an above-ground test, the radioactive debris released to the atmosphere was reduced by a factor of ten.[19] Theoretical work began on possible containment schemes.[19]

Dust raised by Plumbbob Rainier.
Layout of the Plumbbob Rainier tunnel.

Plumbbob Rainier was detonated at 899 ft underground on 19 September 1957.[17] The 1.7 kt explosion was the first to be entirely contained underground, producing no fallout.[20] The test took place in a 1,600[21] – 2,000 ft[22] horizontal tunnel in the shape of a hook.[22] The hook "was designed so explosive force will seal off the non-curved portion of tunnel nearest the detonation before gases and fission fragments can be vented around the curve of the tunnel's hook."[22] This test would become the prototype for larger, more powerful tests.[20] Rainier was announced in advance, so that seismic stations could attempt to record a signal.[23] Analysis of samples collected after the test enabled scientists to develop an understanding of underground explosions that "persists essentially unaltered today."[23] The information would later provide a basis for subsequent decisions to agree to the Limited Test Ban Treaty.[23]

Cannikin, the last test at the Amchitka facility was detonated on 6 November 1971. At approximately 5 megatons, it was the largest underground test in US history.[24]

Effects

Relative crater sizes and shapes resulting from various burst depths.

The effects of an underground nuclear test may vary according to factors including the depth and yield of the explosion, as well as the nature of the surrounding rock.[25] If the test is conducted at sufficient depth, the test is said to be contained, with no venting of gases or other contaminants to the environment.[25] In contrast, if the device is buried at insufficient depth ("underburied"), then rock may be expelled by the explosion, forming a crater surrounded by ejecta, and releasing high-pressure gases to the atmosphere (the resulting crater is usually conical in profile, circular, and may range between tens to hundreds of metres in diameter and depth[26]). One figure used in determining how deeply the device should be buried is the scaled depth of burial, or -burst.[25] This figure is calculated as the burial depth in metres divided by the cube root of the yield in kilotons. It is estimated that, in order to ensure containment, this figure should be greater than 100.[25][27]

Zones in surrounding rock
Name Radius[26]
Melt cavity 4 – 12 m/kt1/3
Crushed zone 30 – 40 m/kt1/3
Cracked zone 80 – 120 m/kt1/3
Zone of irreversible strain 800 – 1100 m/kt1/3

The energy of the nuclear explosion is released in one microsecond. In the following few microseconds, the test hardware and surrounding rock are vaporised, with temperatures of several million degrees and pressures of several million atmospheres.[25] Within milliseconds, a bubble of high-pressure gas and steam is formed. The heat and expanding shock wave cause the surrounding rock to vaporise, or be melted further away, creating a melt cavity.[26] The shock-induced motion and high internal pressure cause this cavity to expand outwards, which continues over several tenths of a second until the pressure has fallen sufficiently, to a level roughly comparable with the weight of the rock above, and can no longer grow.[26] Although not observed in every explosion, four distinct zones (including the melt cavity) have been described in the surrounding rock. The crushed zone, about two times the radius of the cavity, consists of rock that has lost all of its former integrity. The cracked zone, about three times the cavity radius, consists of rock with radial and concentric fissures. Finally, the zone of irreversible strain consists of rock deformed by the pressure.[26] The following layer undergoes only an elastic deformation; the strain and subsequent release then forms a seismic wave. A few seconds later the molten rock starts collecting on the bottom of the cavity and the cavity content begins cooling. The rebound after the shock wave causes compressive forces to build up around the cavity, called a stress containment cage, sealing the cracks.[28]

Several minutes to days later, once the heat dissipates enough, the steam condenses, and the pressure in the cavity falls below the level needed to support the overburden, the rock above the void falls into the cavity, creating a rubble chimney. Depending on various factors, including the yield and characteristics of the burial, this collapse may extend to the surface. If it does, a subsidence crater is created.[26] Such a crater is usually bowl-shaped, and ranges in size from a few tens of metres to over a kilometre in diameter.[26] At the Nevada Test Site, 95 percent of tests conducted at a scaled depth of burial (SDOB) of less than 150 caused surface collapse, compared with about half of tests conducted at a SDOB of less than 180.[26] The radius r (in feet) of the cavity is proportional to the cube root of the yield y (in kilotons), r = 55 * y3; a 8 kiloton explosion will create a cavity with radius of 110 feet.[28]

Rubble mound formed by Whetstone Sulky.

Other surface features may include disturbed ground, pressure ridges, faults, water movement (including changes to the water table level), rockfalls, and ground slump.[26] Most of the gas in the cavity is composed of steam; its volume decreases dramatically as the temperature falls and the steam condenses. There are however other gases, mostly carbon dioxide and hydrogen, which do not condense and remain gaseous. The carbon dioxide is produced by thermal decomposition of carbonates, hydrogen is created by reaction of iron and other metals from the nuclear device and surrounding equipment. The amount of carbonates and water in the soil and the available iron have to be considered in evaluating the test site containment; water-saturated clay soils may cause structural collapse and venting. Hard basement rock may reflect shock waves of the explosion, also possibly causing structural weakening and venting. The noncondensible gases may stay absorbed in the pores in the soil. Large amount of such gases can however maintain enough pressure to drive the fission products to the ground.[28]

Radioactivity release during Baneberry.

Escape of radioactivity from the cavity is known as containment failure. Massive, prompt, uncontrolled releases of fission products, driven by the pressure of steam or gas, are known as venting; an example of such failure is the Baneberry test. Slow, low-pressure uncontrolled releases of radioactivity are known as seeps; these have little to no energy are not visible and have to be detected by instruments. Late-time seeps are releases of noncondensable gases days or weeks after the blast, by diffusion through pores and crack, probably assisted by a decrease of atmospheric pressure (so called atmospheric pumping). When the test tunnel has to be accessed, controlled tunnel purging is performed; the gases are filtered, diluted by air and released to atmosphere when the winds will disperse them over sparsely populated areas. Small activity leaks resulting from operational aspects of tests are called operational releases; they may occur e.g. during drilling into the explosion location during core sampling, or during the sampling of explosion gases. The radionuclide composition differs by the type of releases; large prompt venting releases significant fraction (up to 10%) of fission products, while late-time seeps contain only the most volatile gases. Soil absorbs the reactive chemical compounds, so the only nuclides filtered through soil into the atmosphere are the noble gases, primarily krypton-85 and xenon-133.[28]

The released nuclides can undergo bioaccumulation. Iodine-131, strontium-90 and caesium-137 are concentrated in milk of grazing cows; cow milk is therefore a convenient, sensitive fallout indicator. Soft tissues of animals can be analyzed for gamma emitters, bones and liver for strontium and plutonium, and blood, urine and soft tissues are analyzed for tritium.[28]

Although there were early concerns about earthquakes arising as a result of underground tests, there is no evidence that this has occurred.[25] However, fault movements and ground fractures have been reported, and explosions often precede a series of aftershocks, thought to be a result of cavity collapse and chimney formation. In a few cases, seismic energy released by fault movements has exceeded that of the explosion itself.[25]

International treaties

Signed in Moscow on August 5, 1963 by representatives of the United States, the Soviet Union, and the United Kingdom, the Limited Test Ban Treaty agreed to ban nuclear testing in the atmosphere, in space, and underwater.[6] Due to the Soviet government's concern about the need for the on-site inspections, underground tests were excluded from the ban.[6] 108 countries would eventually sign the treaty, with the significant exception of China.[29]

In 1974, the United States and the Soviet Union signed the Threshold Test Ban Treaty, which banned underground tests with yields greater than 150 kilotons.[30] By the 1990s, technologies to monitor and detect underground tests had matured to the point that tests of one kiloton or over could be detected with high probability, and in 1996 negotiations began under the auspices of the United Nations to develop a comprehensive test ban.[29] The resulting Comprehensive Nuclear-Test-Ban Treaty was signed in 1996 by the United States, Russia, United Kingdom, France, and China.[29] However, following the United States Senate decision not to ratify the treaty in 1999, it is still yet to be ratified by 8 of the required 44 'Annex 2' states and so has not entered into force as United Nations law.

Monitoring

In the late 1940s, the United States began to develop the capability to detect atmospheric testing using air sampling; this system was able to detect the first Soviet test in 1949.[30] Over the next decade, this system was improved, and network of seismic monitoring stations was established to detect underground tests.[30] Development of the Threshold Test Ban Treaty in the mid-1970s led to an improved understanding of the relationship between test yield and resulting seismic magnitude.[30]

When negotiations began in the mid-1990s to develop a comprehensive test ban, the international community was reluctant to rely upon the detection capabilities of individual nuclear weapons states (especially the United States), and instead wanted an international detection system.[30] The resulting International Monitoring System consists of a network of a total of 321 monitoring stations and 16 radionuclide laboratories.[31] Fifty "primary" seismic stations send data continuously to the International Data Center, along with 120 "auxiliary" stations which send data on request. The resulting data is used to locate the epicentre, and distinguish between the seismic signatures of an underground nuclear explosion and an earthquake.[30][32] Additionally, eighty radionuclide stations detect radioactive particles vented by underground explosions. Certain radionuclides constitute clear evidence of nuclear tests; the presence of noble gases can indicate whether an underground explosion has taken place.[33] Finally, eleven hydroacoustic stations[34] and sixty infrasound stations[35] monitor underwater and atmospheric tests.

See also

Notes and references

43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.


Template:Nuclear Technology

  1. 1.0 1.1 Template:Cite web
  2. 2.0 2.1 2.2 2.3 One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting

    In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang

    Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules

    Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.

    A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running

    The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more

    There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang
  3. 3.0 3.1 3.2 One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting

    In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang

    Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules

    Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.

    A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running

    The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more

    There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang Template:Dead link
  4. Template:Cite web
  5. 5.0 5.1 5.2 Template:Cite web
  6. 6.0 6.1 6.2 6.3 Template:Cite web
  7. 7.0 7.1 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  8. Template:Cite web
  9. Template:Cite web
  10. 10.0 10.1 10.2 Template:Cite web
  11. Some sources identify later tests as the "first." Adushkin (2001) defines such a test as "the near-simultaneous detonation of one or more nuclear charges inside one underground excavation (a tunnel, shaft or borehole)", and identifies Uncle as the first.
  12. Some sources refer to the test as Jangle Uncle (e.g., Adushkin, 2001) or Project Windstorm (e.g., DOE/NV-526, 1998). Operation Buster and Operation Jangle were initially conceived as separate operations, and Jangle was at first known as Windstorm, but the AEC merged the plans into a single operation on 19 June 1951. See Gladeck, 1986.
  13. 13.0 13.1 Template:Cite web
  14. 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  15. 15.0 15.1 15.2 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  16. 16.0 16.1 Template:Cite web
  17. 17.0 17.1 Template:Cite web
  18. According to the Nuclear Weapons Archive, the yield is described as "slight", but was approximately 55 tons.
  19. 19.0 19.1 19.2 One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting

    In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang

    Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules

    Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.

    A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running

    The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more

    There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang
  20. 20.0 20.1 Template:Cite web
  21. 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  22. 22.0 22.1 22.2 Template:Cite web
  23. 23.0 23.1 23.2 Template:Cite web
  24. Template:Cite web
  25. 25.0 25.1 25.2 25.3 25.4 25.5 25.6 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  26. 26.0 26.1 26.2 26.3 26.4 26.5 26.6 26.7 26.8 Template:Cite web
  27. Hawkins and Wohletz specify a figure of 90-125.
  28. 28.0 28.1 28.2 28.3 28.4 The Containment of Underground Nuclear Explosions. (PDF) . Retrieved on 2010-02-08.
  29. 29.0 29.1 29.2 Template:Cite web
  30. 30.0 30.1 30.2 30.3 30.4 30.5 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  31. Template:Cite web
  32. Template:Cite web
  33. Template:Cite web
  34. Template:Cite web
  35. Template:Cite web