Chapter 5 (p71-84) in Old Issues and New Strategies in Arms Control and 
Verification, edited by James Brown, Vu Univ. Press, Amsterdam, 1995
_____________________________

Chapter in SMU book (12/9/94)
Old Issues and New Strategies in Arms Control and Verification
 
The Intersection of NPT Renewal, 
IAEA Enhancement and CTB Negotiations
 
David Hafemeister1
Physics Department
California Polytechnic State University
San Luis Obispo, CA 93407
 
I.  NPT Renewal in 1995
 
	In spite of nonproliferation successes in South Africa, China, 
France, Brazil, and Argentina, the NPT regime has suffered some severe 
set-backs in Israel, India, Pakistan, Iraq and North Korea. Because of 
these storm clouds and because of the large amounts of potentially 
available highly-enriched uranium and plutonium in the former Soviet 
Union, it is important to strengthen nonproliferation measures at the 
time of the 1995 renewal of the the Non-Proliferation Treaty.  The NPT 
divides nations into the two classes, nuclear weapons states (NWS) and 
non-nuclear weapons states (NNWS).  Significant nonproliferation gains 
can succeed only when all Parties to the NPT concede some aspects of 
their sovereignty.  To enhance the balance of obligations for the two 
classes of NPT parties, a reasonable approach would be the simultaneous 
negotiation of a Comprehensive Test Ban (CTB) Treaty and the enhancement 
of the IAEA (International Atomic Energy Agency).  A CTB would constrain 
all the NWSs and those NNWSs that might wish to test, while enhanced IAEA 
procedures and inspections would primarily constrain the NNWSs.  The NWSs 
are often less aware of the sovereignty issue because they are not 
required to give up nuclear weapons or have significant required 
inspections.  However, the NWSs should respond to the vague, but 
nevertheless politically-real de facto linkage of NPT Articles II (NNWS 
give up the bomb) and Article VI (NWS negotiate to cease the nuclear arms 
race) and the NPT Preamble ("seek to achieve the discontinuance of all 
test explosions of nuclear weapons for all time") if they want an 
enhanced IAEA.
 
	The Nuclear Nonproliferation Treaty (NPT) continues to be the 
main legal barrier to the further proliferation of nuclear weapons, but 
clearly there are troubling issues which may prevent the unlimited 
renewal of NPT at the Renewal Conference.  It is, perhaps, most likely to 
expect a limited renewal2 of 25 years.  A less desirable result would be 
a conditional renewal of perhaps five years.  Understandably, the U.S. 
prefers a consensus document without taking a vote and without 
considering amendments to the treaty.  To re-examine the basic bargains 
of the Treaty would be as contentious for NWSs as it would be for the 
smaller U.S. states to consider proportional representation in the U.S. 
Senate at a constitutional convention.  A lack of consensus at the time 
of NPT renewal would complicate the adoption of several possible 
strengthening measures for the IAEA. 
 
	NPT Successes:  The NPT regime has had both successes and 
failures3 in recent years.  Treaty adherence has continued to grow to an 
impressive 170 nations.  The NPT adherence by China and France has 
greatly strengthened the global nonproliferation regime because now all 
five NWSs (the five victors of World War II) are legally committed to the 
NPT.  After two decades of a clandestine program, South Africa has 
dismantled its six Hiroshima type uranium weapons and acceded to the 
NPT.  After a slow start in Iraq, the UNSCOM and IAEA inspections have 
compiled considerable evidence on Iraq's NPT violations and destroyed its 
clandestine facilities.  Because of the NPT and other reasons, Belarus, 
Kazakhstan and Ukraine are headed towards NNWS status.  Because of the 
new awareness of violations at undeclared sites, the IAEA has enhanced 
its role in several ways (Sec. III).  To put a good face on the North 
Korean violations, one can say that the NPT regime gave the international 
community the legal and political tools to pressure this nation to give 
up its nuclear weapons program.  Most significantly, the NPT regime has 
walked these half-dozen and an additional half-dozen more states away 
from their violations of NPT norms.
 
	The Eisenhower Atoms for Peace policies were the precursors for 
today's NPT/IAEA regime which must deal with the NPT failures listed 
below.  Of course, some technology transfer took place because of this 
regime, but the establishment of a global norm with an international 
inspectorate will hopefully be the predominant legacy for the future.  
Some critics would like to replace the IAEA with a UN Security Council 
organizationl, but it is difficult to imagine that the UN could recreate 
the IAEA's functions without suffering from threats of vetoes in the 
Security Council.
 
	NPT Failures:  The IAEA did not detect violations at the declared 
sites of NPT-Party Iraq while Iraq created a clandestine $10 billion, 
multi-approach nuclear weapons program at undeclared facilities.  This 
fiasco was the biggest failure to date of the NPT regime.  It should be 
underscored that the IAEA did not receive intelligence information from 
the Western nations that had some key data on their imports of sensitive 
technology.  The lack of intelligence information was the major cause 
behind the IAEA's failure to request special inspections at undeclared 
sites.  However, the IAEA had never before made such requests.  If blame 
is to be placed, it should be put firmly on the front door of the Western 
nations which ignored their own intelligence data and continued to sell 
abundant amounts of dual-use technologies to Iraq without drawing the 
very obvious conclusions from the known flow of these materials.  It has 
been clear for some time that the NPT/IAEA regime does a credible job on 
materials accounting on enriched uranium, and a less credible job on 
plutonium reprocessing at declared sites.  It should be no surprise that 
the IAEA does not significantly address materials accounting at 
undeclared sites.
 
	The following list of NNWSs have made contact with some aspects 
of nuclear weapons programs:
 
	--	de facto NWS (India, Israel, Pakistan)
	--	past-de facto NWS (South Africa)
	--	attempting NWS (Iraq, Iran, North Korea)
	--	past-attempting NWS (Argentina, Brazil, South Korea, 
Sweden, Taiwan)
	--	transitional NWS/NPT FSU (Belarus, Kazakhstan, Ukraine)
	--	flirting NWS (Libya, Algeria)
	--	NWS (U.S., Russia, U.K., France, China)
 
Some of these NNWS's can be listed as NPT successes (South Africa, 
past-attempting NWS, temporary FSU) and some can be listed as NPT 
failures.  Summing over these various categories, we obtain:
 
	de facto NWS = 3	past de facto NWS = 1	attempt NWS = 3
	past attempt NWS = 5	NWS/NPT/FSU NWS = 3	flirt NWS = 2
 
Adding these categories, we obtain:
 
		NWS = 5		NNWS with NWS aspects = 17
 
	Special Nuclear Materials by NPT Compliant States:  Russia, the 
nuclear successor state to the Soviet Union, possesses vast amounts of 
nuclear materials4 in a very uncertain time.  Minatom Minister Victor 
Mikhailov has declared that Russia had some 45,000 warheads and 
stock-piled isotopes which contain some 100 tonnes of plutonium and 1,250 
tonnes of highly-enriched uranium.  The  3,000 warheads in Ukraine and 
Kazakhstan are probably included in this total.  As the U.S purchases 500 
tonnes of highly enriched uranium (HEU) from Russia and one-half tonne 
from Kazakhstan, this does not solve the entire problem.  While 
questionable economics has convinced most nations to forgo a plutonium 
economy with breeder reactors, three nations (France, Japan and Russia) 
are propelled by the momentum of their institutions to stay the course 
for a full plutonium economy of breeders and reprocessing.  (UK mainly 
reprocesses for others.)  The IAEA cannot meet its materials accounting 
detection standard of 8 kilograms of plutonium at a reprocessing plant 
unless considerably more resources are given to it.  Privately, the U.S. 
and other nations prefer that these plutonium programs be canceled, but 
they do not wish to complicate other aspects of their foreign relations 
with these four nations by pressing too firmly.  The political aspects of 
energy independence are far more important for Japan and France than for 
the U.S. and Russia.  Russia's Minatom officials claim that they wish to 
build several breeder reactors in the future.  It would be unwise if 
Russia invested in a plutonium economy any part of the $12 billion it 
will receive from the U.S. for its diluted HEU.  Plentiful supplies of 
enriched uranium from dismantled nuclear weapons and the ample ability to 
enrich more has clearly reduced the importance of the breeder for at 
least the next 50 years.

II.  Revisiting the NWS/NNWS Basic Bargain.
 
	The NPT is an acknowledgement that nuclear proliferation is 
harmful to both NWSs and NNWSs.  In particular, NNWSs recognize that the 
nuclear weapons of their neighboring rival nations are more fearsome to 
them than the nuclear weapons of the NWSs.  To reduce the fears of the 
NNWSs, in 1978 the U.S. gave the negative security assurances that the 
U.S. would not use nuclear weapons on NNWSs as long as they are indeed 
NNWSs and are not allied to NWSs.  Beyond this basic premise, the NPT has 
balancing provisions in the NPT Articles listed below:
 
		NWS					NNWS			
(1) Don't help with nuclear weapons		(2)  Don't try to acquire 
nuclear weapons
Accept some voluntary safeguards............	(3)  Accept full scope 
safeguards
(4)  Help with nuclear power
(6)	negotiate in good faith the cessation 
	of the nuclear arms race and a treaty
	on general and complete disarmament
 
	On balance, the NNWSs gave up more of their their national 
sovereignty than the NWSs because the NNWSs accepted full-scope 
safeguards on all of their nuclear facilities and they voluntarily 
renounced future ownership of nuclear weapons.  It is true that in 1968 
and in 1980 the U.S. voluntarily agreed to accept IAEA safeguards on all 
of its non-weapons nuclear facilities, but it is unlikely that the IAEA 
will actually carry out this offer on all the NWSs facilities because of 
the large cost and because the NWSs already have a great deal of nuclear 
materials for their weapons programs. 
 
III.  IAEA Enhancement
 
	Since it is most likely that the NPT will not be amended, 
enhancements to the NPT regime will primarily take place through measures 
supported by the IAEA5 Board of Governors, by the Nuclear Suppliers Group 
or by new possible treaties, such as the one banning of weapons grade 
fissile materials.  The term IAEA enhancement may have a different 
meaning to the NNWS members than to the NWS members because these 
enhancements mostly impact the "nuclear have-not nations."  Since the 
vast majority of the members of the IAEA Board of Governors are NNWSs, 
the NNWS nations will have to convince their citizens that additional 
losses in sovereignty will actually enhance their national security, 
rather than detract from it.  The final adoption of the IAEA enhancements 
will require that the NNWS dominated board be convinced that a little 
more inequality is good for them.
 
	There are many ideas for enhancing6 the IAEA's ability to detect 
proliferation with enough credibility to take the violation to the U.N. 
Security Council.  Lacking concrete action, aggrieved nations might 
simply destroy the nuclear facilities with acts of 
"counter-proliferation," much as Israel (1981) and the U.S. (1991) did to 
Iraq.  Because of the new awareness of violations at undeclared sites, 
the IAEA has enhanced its role in several ways with:  A more vigorous 
"special inspection" policy, the establishment of a very small office to 
receive intelligence information submitted by IAEA member states, the 
continued presence of the IAEA in monitoring Iraq, and the collection of 
"environmental" samples to establish base-line data to help determine the 
validity of future violations.  Some of the other ideas to enhance the 
IAEA are:
 
-- Wider use of Special Inspections of undeclared and declared sites.  If 
these inspections were carried out more frequently, they would lose their 
inquisitional image.  The challenge inspections from Conventional Forces 
in Europe (CFE) Treaty are considered to be far more effective for 
deterring violations than the normally scheduled routine inspections.  
Because these challenge inspections are expected and natural, they do not 
naturally incite criticisms.   
 
-- Very Short Notice Inspections of undeclared and declared sites.  By 
using permanent visas for quick-entry visits and without requiring 
consultations in advance, inspectors could move to trouble spots before 
the evidence was removed.
 
-- Automated Near Real-Time Remote Data Acquisition using modern 
electronics and satellite communications.  The use of CCD cameras and 
other advanced technologies could save considerable funds, particularly 
for those nations which have extremely large uranium nuclear power 
programs.  The savings could be used to target other proliferation 
concerns.  These automated data acquisitions would have to be 
supplemented by short-notice inspections.
 
-- Requirement of Full-Scope Safeguards on all nuclear exports by all 
IAEA members.
 
-- Requirement of Full Scope Safeguards on all nuclear facilities in all 
NNWS-IAEA states, removing the two tiered distinctions (INFCIRC 66 and 153).
 
-- Enhanced intelligence sharing with the IAEA.
 
-- Dual-use export lists shared with the IAEA.
 
-- Adoption of nuclear proliferation sensors on "Open Skies" platforms 
and expanded global adoption of Open Skies.
 
IV.  NPT-CTB Linkage.
 
	In two of the four NPT Review Conferences (1980 and 1990) the 
States Parties failed to produce a consensus document primarily because 
the NNWSs were concerned about the lack of progress by the NWSs on their 
Article VI commitments.  The NPT and the CTB are linked in the key arms 
control agreements:  The 1963 Limited Test Ban Treaty ("Seeking to 
achieve the discontinuance of all test explosions of nuclear weapons for 
all time"), the 1970 NPT, the 1974/1990 Threshold Test Ban Treaty and its 
Senate Resolution of Ratification, and the 1990 unadopted Mexican NPT 
Review Conference Report ("achievement of a multilateral comprehensive 
test ban treaty prior to 1995 must continue to be accorded absolute 
priority, as the single most important measure relating to cessation of 
the nuclear arms race at an early date, and the continued testing of 
nuclear weapons by nuclear-weapon States Parties to this Treaty would put 
the future of the Non-Proliferation Treaty beyond 1995 in grave doubt.").
 
	The NPT/CTB linkage between nonproliferation and nuclear testing 
is overstated in the sense that a CTB will not roll back the de facto 
proliferant states to being proper non-nuclear states.  In fact, the 
cessation of the nuclear arms race is much more dependent on the START 
treaties than a CTB.  However, this argument is not absolute, and, in 
fact, because of the political perception of the importance of the CTB, 
it can, in the last analysis, considerably strengthen the NPT regime in 
the following ways:
 
	IAEA Enhancement:  Because there is a perception by the NNWSs 
that a CTB is sine qua non for the NWSs to fulfil their side of the NPT, 
the voting patterns of the NNWSs in the IAEA Board of Governors will be 
influenced by the outcome on the CTB.  Put plainly, if the NWSs want the 
NNWSs to accept more intrusive measures which reduce the NNWS sovereign 
status, then the NWSs have to offer more constraints on themselves.
 
	Regional Proliferation:   The Indians have stated that they would 
join a CTB if China was also a party to the CTB.  If these two nations 
were CTB Parties, there would be considerable pressure for Pakistan to 
follow suit.  A CTB on the Indian-Pakistan subcontinent would not ensure 
an end to their nuclear arms race, but it certainly would slow 
proliferation in that area, and begin a process in which proliferation 
might actually be rolled back.  The same can be said for the Korean 
Peninsula, the Middle East and South America.
 
	Nonproliferation Norms:  The list of 17 NNWSs with some degree of 
past or present nuclear weapons status is of grave concern.  The global 
norm for nonproliferation has received severe body blows and it now needs 
revitalization.  A renewed NPT with an enhanced IAEA and a completed CTB 
would give the diplomatic impetus to do this.
 
	Decision Making at the Highest Levels:   Reportedly, all five 
NWSs were successful on their first try.  The usual response to this fact 
is that making nuclear weapons is very easy on the first try.  Therefore, 
a nation does not need to test to have confidence that it has viable 
nuclear weapons.  This argument may succeed among the scientists and 
engineers that have built the weapon, but consider the role of the 
presidents of the "wannabe" nuclear states.  Normally, national leaders 
are not picked from the ranks of the scientists who are on tap but never 
on top, but rather they are chosen from the humanities, law, military, or 
business professions.  Would a nonscientist president of a lesser 
developed country and their military leaders wish to establish a new 
nuclear weapons program knowing that it would be very difficult to test 
the weapons before they were used?  At the highest levels in the LDC 
governments, the package of an NPT with an enhanced-IAEA and a CTB, and 
the uncertainty in the quality of their nuclear scientist's work could 
tip the balance towards abstinence.

V.  Monitoring a CTB. 
 
	TTBT Monitoring:  Monitoring7 a CTB would be very different from 
the monitoring of the 1974 Threshold Test Ban Treaty (TTBT).  The TTBT 
restricted the two superpowers, while a global CTB would constrain some 
175 NNWSs, as well as the NWSs.  TTBT monitoring determined a threshold 
yield of 150 kilotons primarily based on measurements of teleseismic 
waves that traveled through the interior of the Earth.  Because the 
tectonic plate below the Nevada site has been extended and partially 
melted, seismic waves from the Nevada Test Site explosions are more 
reduced in magnitude by absorption than the explosions at the Soviet 
sites which have had no recent geological activity.  Because of this 
difference, the U.S. explosions appear relatively smaller in yield as 
compared to explosions of the same yield in Russia.  Parts of the U.S. 
policy community purposefully ignored the true value of this magnitude 
correction to charge the Soviets with a "likely violation" of the TTBT.  
This guilty charge greatly retarded negotiations with the Soviets on both 
the TTBT and CTB.  In 1988 Acting Assistant Secretary of Defense Frank 
Gaffney stated8:
 
"The thinking goes like this: the more time wasted on discussion and 
experimentation of monitoring techniques irrelevant to the verification 
of an environment in which there are no legal tests, the easier it will 
be to stave off demands for the more constraining comprehensive test ban."
  
The seismic magnitude correction between the two test sites was estimated 
in many ways, including the observation of Lg surface waves,  prior to 
the 1988 Joint Verification Experiment which used CORRTEX at the two 
sites.  Ultimately, the policy community accepted the scientific facts 
from its own scientists and used the true value of the bias correction.  
Finally, the U.S. charge of a "likely violation" was dropped in 1990.  
Unfortunately, the whole issue of Soviet compliance overly politicized8 
the science, retarding negotiations on the CTB and on other arms control 
agreements.
 
	  CTB Monitoring:  The CTB requires a different monitoring9,10 
approach.  Rather than determining compliance with a 150 kiloton 
threshold, CTB monitoring requires the detection and identification of a 
nuclear explosion rather than the quantification of a nuclear yields down 
to levels of about 1 kiloton.  Roughly speaking, a 1 kiloton explosion, 
tightly coupled (tamped)  in hard rock, will have a seismic magnitude of 
about mb = 4.  In contrast, a so-called decoupled explosion set off 
within a large cavity will have a smaller value of mb.  In its 1988 
report, OTA concluded that "by 1991, any well-coupled explosion with a 
magnitude corresponding to 1-2 kilotons that is detonated anywhere on 
Earth will have a high probability of being detected and located...."  
Advances in technology have further strengthened this conclusion so that 
it is generally accepted that a coupled explosion of about 0.1 kiloton 
could be detected and identified with the types of networks now being 
proposed.  For example, OTA concluded for the case of tests in the USSR:  
"Based on cautious assumptions for a network of 30 internal arrays [to 
USSR] or about 50 three-component internal stations, it appears likely 
that a detection threshold of 2.5 mb (90 percent probability of detection 
at four or more stations) could be reached."  Since it is more difficult 
to identify than detect, one should generally add about 0.5 mb units to 
the detection level when discussing identification.  
 
	  The U.S. Advanced Research Projects Agency (ARPA) of the 
Department of Defense has developed four highly successful arrays in 
Scandinavia and Germany, which compliment a U.S. global network of 
seismographs to monitor the test sites in the western part of the Soviet 
Union.  The arrays are capable of detection down to the 2.2 mb seismic 
level (90% probability of 1 of the 4 arrays detecting the event) by 
"beamforming" the seismic signals to remove local background noise and 
amplify the signal.  The NORESS array consists of 25 individual 
seismographs over a 3 km diameter circle, and it is designed primarily to 
monitor in the 1-10 Hertz band.  ARPA has suggested9 a global network of 
some 50 seismic arrays, along with individual seismic stations, that 
would be able to detect, identify, and locate explosions of one kiloton 
in a cavity ("fully decoupled" with mb = 2.5).  The 2.5 mb level also 
corresponds to a well-coupled yield of 0.01 to 0.1 kilotons.  In 
addition, ARPA has suggested a near-global capability to detect, identify 
and locate decoupled 5 kilotons explosions (mb = 3).  The ARPA proposal 
would be capable of estimating locations of explosions to within 10 
kilometers, facilitating collection of data by other sensors.  The U.S. 
delegation proposal containing these elements was adopted by the Group of 
Scientific Experts, a subcommittee of the Conference on Disarmament in 
Geneva.  The proposal would establish a new international seismic center 
that would continuously incorporate near real-time data from the 50 
seismic arrays (the alpha network) and the seismic stations (the beta 
network described below).  The seismic data from the alpha and beta 
stations would be available in near real-time, minutes after an event, 
and it would be entirely unclassified and available to all participants 
for analysis.
 
	The Incorporated Research Institutions for Seismology (IRIS), 
working with the U.S. Geological Survey, coordinates a Global 
Seismographic Network (GSN) of seismic stations throughout the world.  
These modern three-component seismographs can measure a broad-band of 
frequencies between 0.1 and 20-80  Hertz.  IRIS plans10 to establish a 
network of 128 seismic stations at a spacing of about 2000 kilometers, or 
less, shown in Fig. 1.  The large number of stations would facilitate 
measurements at the sub-regional level of the higher seismic frequencies, 
which are relevant for "decoupled" nuclear explosions.
 
**** Fig. 1 ****
 
	Model calculations by Claassen, Unger and Leith11 show that the 
present network of 79 stations (including the four alpha arrays) on the 
Eurasian continent can typically detect down to the 3.6 mb level (90% 
probability that four P-wave arrivals will be observed at 4 different 
stations).  They also project that a network increased to 128 stations 
would be able to typically detect a threshold of 3.2 mb, as shown in Fig. 
2.  If the criteria of 4 P-wave arrivals is relaxed to 2 P-wave and 2 
S-wave arrivals, the typical detection level is lowered to 2.8 mb.  For 
the regional networks to be most successful it will be necessary to study 
the regional seismic characteristics.
 
**** Fig. 2 ****
 
VI.  CTB Compliance Concerns
 
	The combination9,10 of the near real-time alpha network of arrays 
and the beta network of broad-band triple-axes seismographs should be 
able to monitor coupled nuclear tests to less than one  kiloton.  
However, there are other issues7,12 to be discussed:
 
	Decoupled Explosions:  If a nuclear weapon is placed in a cavity 
of sufficient size, such that the blast pressure on the cavity wall is 
below the elastic limit of the surrounding media, the seismic signal 
strength can be reduced by a factor of 7-70.  The cavity size necessary 
to obtain these decoupling factors has a radius of 20-25 meters.  Radii 
half this size would partially decouple the explosion.  Because the 
cavity radius scales with the cube root of the yield for a fixed 
decoupling factor, one can estimate the relevant cavity size for other 
yields.  If a one kiloton weapon had an error of a factor of five in its 
yield, or five kilotons, it would require a cavity that was a factor of 
1.7 larger, or a radius of 35-45 meters (diameter of 70-90 meters).  It 
should be pointed out that approximately 30% of Soviet tests vented and 
the U.S. had severe venting problems with its earliest tests.  In 
particular, it appears that smaller tests can be harder to contain than 
larger ones.  The last four U.S. explosions that vented were from 
explosions with yields less than 20 kilotons.  It is hypothesized that 
smaller explosions would not sufficiently glassify the cavity, and also 
would not rebound sufficiently to close fractures with a stress cage.  
Thus, the smaller explosions, which one might think were easier to hide, 
are more likely to vent and could be detected by the release of 
radioactivity.  For these same reasons, it is further hypothesized that 
partially decoupled tests would also be difficult to completely contain.  
There is very little data on decoupled tests in cavities, and none have 
been carried out with yields greater than one kiloton.  Other 
intelligence means can also gather evidence on clandestine decoupled 
nuclear tests.  It is widely felt that a clandestine execution of a few 
kiloton or larger shot, that was decoupled to a degree that enabled the 
test to escape detection by seismic means and which did not have yield 
excursions, would require the resources of a very technologically 
sophisticated nation.     
 
	Frequency Dependence:  Reduction in apparent yield by muffling 
depends greatly on the frequencies examined by the seismographs.  A 
reduction of a factor of 70 for frequencies less than about 7 Hertz is 
observed, while at higher frequencies the reduction will be much less 
severe, about a factor of 7 at 20 Hertz.  Nuclear explosions produce more 
higher frequency seismic waves than earthquakes.  Close-in regional 
seismic stations should be able to detect the higher frequencies which 
are more easily absorbed by the Earth.  Because of the additional 
spectral data, the seismographs which have been designed to measure 
higher frequencies should also be useful to distinguish nuclear 
explosions from earthquakes and from ripple-fired chemical explosions.
 
	Requirement of Detection of Decoupled Explosions:  A verification 
regime that required the detection of decoupled 1 kiloton explosions (2.5 
mb) would, of course be useful, but it may not be necessary when one 
considers the increased costs.  In addition, since the number of small 
earthquakes rises by about a factor of three for a reduction of 0.5 mb in 
threshold, the analysis requirements will also rise.  Politically, the 
issue of evasion scenarios greatly complicated the negotiation of a CTB 
in the 1960s, but in the 1990s the discussion has to be considered in 
terms of a different calculus.  A nation that wished to secretly test its 
first nuclear weapon would have to be sure that it could predict the 
yield of the weapon to better than a factor of about two in order to 
ensure that the cavity actually decoupled the test, and that other 
intelligence means did not reveal the test.  Undoubtedly, the combination 
of differing capabilities from the alpha arrays and the beta stations 
would synergistically work well together, and the threshold detection 
level will drop with time as the networks expand and the regional 
seismology is improved.  In light of these concerns, the evasion scenario 
of testing in cavities should not be assumed to be credible because of 
(1) uncertain yields of first-time weapons, (2) venting from small 
explosions in cavities, (3) humint and national technical means 
intelligence data.
 
	Probabilities of Detection:  The criterion of "high confidence" 
by the intelligence community usually means that some 90 or 95% of the 
clandestine events should be identified.  In a statistical sense, this 
would mean that about two standard deviations of the events should be 
observable, as compared to the usual scientific error bar of one standard 
deviation.  One would expect that a would-be violator would be deterred 
at a much lower level of confidence, for example, less than 67%, 
corresponding to one standard deviation.  The requirement of 4 stations 
with an identification probability of 90 percent increases the difficulty 
for the global network.  If the requirement is relaxed to 2 stations at 
90% confidence, the mb level drops by about 0.5.
 
	Definition of a Threshold Yield for the CTB:  Defining13 a 
threshold yield in a CTB near the limits of verifiability, for example at 
about one kiloton, should be discouraged because this would legitimize 
testing just under such a yield.  The Australian draft14 CTB avoids this 
pitfall by defining the ban on nuclear testing as to "not carry out any 
nuclear weapon test explosion or any other nuclear explosion."  During 
the Eisenhower moratorium hydronuclear tests were carried out with yields 
up to 0.4 pounds TNT fissile.  Hydrodynamic tests without nuclear yields 
can obtain some of the same test results15 without actually crossing the 
nuclear threshold.  While such tests should be banned for the CTB, one 
cannot rule out announced "peaceful" tests with much smaller fusion 
yields in the unlikely case there is progress on controlled fusion from 
laser pulses for power generation.
 
	Who Verifies the CTB:  The individual nations, aided by their own 
seismological communities, should share the data and make their own 
compliance decisions.  The IAEA is already overly burdened and not 
particularly suited for seismic monitoring.  The draft CTB14 would create 
a new technical organization to monitor the treaty, with provisions that 
allowed one nation to trigger an inspection, language which is similar to 
the Chemical Weapons Convention, rather than the NPT/IAEA regime.

VII.  NPT/CTB National Security Issues
 
	During the Senate consideration of the START Treaty, the issue of 
how much verification is enough was raised.  In response to a question in 
1992 from the Foreign Relations Committee, Secretary of State James 
Baker16 defined of effective verification by stating it must be able to 
verify "if the other side attempts to move beyond the limits of the 
Treaty in any military significant way, we would be able to detect such a 
violation well before it becomes a threat to national security so that we 
are able to respond.  Additionally, the verification regime should enable 
us to detect patterns of marginal violations that do not present 
immediate risk to U.S. security.  However, no verification regime can be 
expected to provide firm guarantees that all violations will be detected 
immediately."
 
	Along the same lines, the new Administration and Congress will 
have to make a finding on the effective verifiability of the CTB Treaty.  
In this calculation, the following factors will have to be considered in 
determining the net gains in U.S. national security from a CTB, as 
compared to the national security losses from possible violations to the 
CTB and the lesser roles of the nuclear weapons labs:
 
	-- Does the present NPT/IAEA regime need of strengthening?  Will 
a CTB be useful in obtaining stronger measures from the IAEA Board of 
Governors?
 
	-- Does the U.S. wish to stop Russia and China from further 
nuclear testing?  Would Russian testing at Novaya Zemlya help promote a 
resurgent Russian bear?  Would further Chinese testing lead China toward 
modernized MIRVed systems?
 
	-- Will the CTB be one of several elements that discourages the 
beginnings of new nuclear weapons programs in NNWSs?
 
	-- Was the U.S. going to deploy new, safer nuclear weapons on 
Trident submarines, Minuteman IIIs and heavy bombers?  Are the 
calculations by Isard17 approximately correct, in which he concludes that 
it would take about a very considerable $200 million to save each life 
based on the costs of testing and deploying new warheads and Trident 
missiles and on the potential number of lives saved from such actions.  
(This results does not consider the nonproliferation gains of not 
testing, for example, as it is generally assumed that Russia will not 
test as long as the U.S. does not test.)
 
	-- What future modernizations of the U.S. nuclear arsenal make 
sense?  In what time frame?  How will the ban on testing effect these 
modernization plans?  Would the global nonproliferation regime be 
enhanced or degraded by the testing and deployment of mini-nuclear 
weapons for counter-proliferation strikes?
 
	-- How difficult would it be for a new NWS to explode an untested 
nuclear weapon in a cavity without venting, without yield excursions, and 
without detection by other intelligence means?
 
	-- How much will the capabilities of the alpha and beta seismic 
stations increase with time?  What size nuclear weapons could be 
clandestinely tested by various types of nations under the CTB?  Would a 
CTB stimulate a more complete international seismic network which could 
both deter and detect violations by NNWSs and NWSs?
 
VIII.  Conclusions  
 
	National Security:  Is there a national security difference to 
the U.S. when a NNWS tests without a CTB as compared to testing under the 
CTB?  Do we expect that clandestine, very small yield explosions would be 
more likely to be carried out by NWSs or NNWSs?  For a NNWS Violation, it 
seems clear that there is essentially no relative loss of national 
security to the U.S. if a nation clandestinely tests under a CTB, as 
compared to testing without a CTB.  In either case, the U.S. would be 
faced with another NNWS with nuclear weapons.  Under the CTB, the U.S. 
would not have a diminished ability to deal with this unfortunate 
situation, and a strengthened NPT/IAEA/CTB regime just might deter the 
clandestine nuclear program.  For a NWS violation, it is unlikely that 
very small clandestine tests by NWSs would create a significant loss in 
U.S. national security that could not be remedied by abrogation.  The 
time needed to greatly enhance the U.S. nuclear triad with a new series 
of nuclear tests is of the order of a decade, so a delay in action is not 
critical for the case of an NWS violation.
 
	Non-Proliferation Gains:  The entrance into force of a CTB would 
greatly stimulate NPT renewal and enhancement of the IAEA in many ways.  
The deterrence effect of a CTB on a proliferant state would initially be 
small, but would grow substantially with time in internal discussions in 
governments considering a nuclear weapons program.  A CTB would deter 
crossing the fusion weapon threshold.
 
	How Much Verification is Enough:  The alpha and beta networks 
should effectively verify the CTB to about one kiloton for a tamped or 
partially tamped weapon.   
 
	Clandestine Cavity Testing:  At most, a clandestine test of 1-2 
kilotons might be successfully carried out by a technologically advanced 
nation.  NWSs could use cavities to test 1-2 kiloton weapons, but they 
would not gain considerable knowledge.  NWS clandestine tests would not 
greatly change their triad forces. Less technically-advanced countries 
would be unlikely to avoid detection by testing a clandestine weapon, but 
one can not rule this out.  It follows that an evasion scenario by 
testing in a cavity should not be a limiting factor for a CTB.
 
Notes
 
1.  Research for this paper was primarily done while serving as a staff 
member of the U.S. Senate Committees on Governmental Affairs and Foreign 
Relations (1990-93).
 
2.  J. Pilat and R. Pendlay, Beyond 1995: The Future of the NPT Regime 
(Plenum Press, NY,1990).
 
3.  U.S. Office of Technology Assessment (OTA), Proliferation of Weapons 
of Mass Destruction  (OTA-ISC-559, Washington, DC, 1993).  L. Spector, 
Nuclear Ambitions  (Westview Press, Boulder, CO, 1990).  U.S. Senate 
Governmental Affairs Comm., Proliferation Threats of the 1990s (S. Hrg. 
103-208, 1993).
 
4.  G. Allison, A. Carter, S. Miller and P. Zilikow, Cooperative 
Denuclearization (Ctr. Science and International Affairs, Harvard Univ. 
1993).  F. Berkhout, et al, "Disposition of Separated Plutonium," Science 
and Global Security 3, p1-53 (1993).  U.S. Senate Governmental Affairs 
Committee, Disposing of Plutonium In Russia (S.Hrg. 103-135, 1993).
 
5.  L. Scheinman, The International Atomic Energy Agency and World 
Nuclear Order  (Resources for the Future, Washington, DC, 1987).
 
6.  A. Fainberg, Strengthening IAEA Safeguards:  Lessons from Iraq  (Ctr. 
International Security and Arms Control, Stanford Univ., 1993).
 
7.  Office of Technology Assessment, Seismic Verification of Nuclear 
Testing Treaties  (OTA-ISC-361, 1988) and The Containment of Underground 
Nuclear Explosions  (OTA-ISC-414, 1989).
 
8.  U.S. Senate Foreign Relations Committee, Test Ban Issues (S.Hrg. 
100-1000, 1988).  G. van der Vink and C. Paine, "The Politics of 
Verification:  Limiting the Testing of Nuclear Weapons," Science and 
Global Security 3, 261-288 (1992).
 
9.  U.S. Delegation to the Group of Scientific Experts at UN/CD-Geneva, 
"Technical Concepts for an International Data Exchange System,"  
(UN/Geneva/CD/GSE/84, Nuclear Monitoring Research Office, Advanced 
Research Projects Agency, DOD, Arlington, VA, Feb./July1993).
 
10.  G. van der Vink, D. Simpson, C. Hennet, T. Wallace and J. Park, 
Nuclear Testing and Nonproliferation:  The Role of Seismology in 
Deterring the Development of Nuclear Weapons,  (Incorporated Research 
Institutions of Seismology (IRIS), Arlington, VA, 1993).
 
11.  J. Claassen, The Potential Monitoring Contribution of the Open 
World-wide Network, Sandia National Laboratory (SAND 93-1931).  J. 
Claassen, J. Unger and W. Leith, IRIS Newsletter 12, 1-7 (Aug. 1993).
 
12.  S. Fetter, Towards a Comprehensive Test Ban  (Ballenger, Cambridge, 
MA, 1988).
 
13.  G. Bunn and R. Timerbaev, "Avoiding the 'Definition' Pitfall To a 
Comprehensive Test Ban," Arms Control Today 23, 15-18 (May 1993).
 
14.  Conference on Disarmament, "Comprehensive Test Ban Treaty:  
Australian Resource Paper on Draft Treaty Elements," CD/NTN/WP/49, March 
30, 1994.
 
15.  T. Zamora Collina and Ray Kidder, "Shopping Spree Softens Test-Ban 
Sorrows," Bulletin of Atomic Scientists 50, 23-29 (July, 1994).
 
16.  U.S. Foreign Relations Committee, The Start Treaty  (Senate Exec. 
Rept. 102-53, 1992), p. 27.
 
17.  U.S. Senate Foreign Relations Comm., Nuclear Testing Moratorium Act, 
S.2064 and Other Nuclear Testing Issues  (S.Hrg. 102-862, 1992).  W. 
Isard, An Economic Analysis of the Costs and Benefits of Ending the U.S. 
Nuclear Testing Moratorium  (Economists Allied for Arms Reductions, 
N.Y.,1993).
 
Figure Captions
 
Fig. 1.  The current and proposed open, global seismic network proposed 
by IRIS.  Data from this dual-purpose network is extremely important for 
monitoring the CTB and for basic and applied seismology.  (Data10 
courtesy of IRIS.)
 
Fig. 2.  Detection threshold estimate in mb(Lg) values with 128 seismic 
stations and arrays.  A probability of 90 percent that at least four 
stations detected the event was used to determine the contours.  (Data11 
courtesy of Claassen, Unger and Leith.)