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Underground Facilities: Intelligence and Targeting Issues

U.S. Intelligence: Hiding of Military Assets by "Rogue Nations" and Other States a Major Security Challenge for 21st Century

U.S. Documents Describe Monitoring Effort Going Back to Early Cold War Years

National Security Archive Electronic Briefing Book No. 439

UPDATE - September 23, 2013

Originally Posted - March 23, 2012

For more information contact:
Jeffrey T. Richelson - 202/994-7000


Iran's underground nuclear sites not immune to U.S. bunker-busters, experts say
By Joby Warrick, The Washington Post
February 29, 2012

Tunnel vision: U.S. intel community seeks new ways to peer into underground sites
By Keith Button, Defense News
August 1, 2009

Unearthing secrets: How the U.S. digs up intelligence on underground sites
By Jeffrey T. Richelson, Defense News
August 1, 2008

Moscow builds bunkers against nuclear attack
By Bill Gertz, The Washington Times
April 1, 1997

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Washington, D.C., September 23, 2013 – While the focus on Syria's chemical weapons use, and the possibility of military action against Syrian government targets pushed aside, for a while, the issue of how to deal with Iran's nuclear program,1 the two situations have one thing in common — their reported reliance on underground facilities to shield the production and storage of weapons of mass destruction.

Documents posted today by the National Security Archive show that such sites in Syria are only the latest in a long line of alleged and real underground facilities that have posed a high priority challenge for U.S. and allied intelligence collection and analysis efforts, as well as for military planners. There may be more than 10,000 such facilities worldwide, many of them in hostile territory, and many presumably intended to hide or protect lethal military equipment and activities, including weapons of mass destruction, that could threaten U.S. or allied interests.

Today's posting features 21 new documents, in addition to the 41 records from the Archive's initial March 23, 2012, posting on this subject. The new materials include several concerning a key topic of Cold War intelligence collection and analysis — hardened and underground communications facilities. Also included for the first time are draft charters for the National Reconnaissance Office (NRO) working group on hardened and buried targets. The majority of the new materials consist of reports from the Asian Studies Detachment (ASD) of the 500th Military Group of the Army Intelligence and Security Command. The ASD reports, based on open source intelligence, focus on various aspects of hardened and buried facilities in North Korea and China.

The 21 new items, with one exception, were acquired via Freedom of Information Act requests or research in the National Archives. The original posting described in detail the agencies and programs the U.S. government has brought to the task of identifying and assessing underground structures in foreign countries since World War II.

* * * * *

Introduction: "Underground Facilities: Intelligence and Targeting Issues" (Updated)

By Jeffrey T. Richelson

The challenge of locating and assessing underground facilities goes back to at least the Second World War. In August 1943, the Germans, in the face of allied aerial attacks, decided to move production of their A-4 (V-2) rocket to an underground facility near Nordhausen. By late 1944, British intelligence was reporting that the facility was producing over thirty rockets a day, while the British Chiefs of Staff wanted to know the feasibility of a bombing campaign to halt or seriously impair production. In her memoirs, Constance Babington-Smith reported examining aerial photographs of Kahla, in the Thuringian Hills, and finding evidence of an underground jet-fighter factory.2

During the Cold War there were two types of underground facilities that were, in some ways, emblematic of the consequences of that war turning into a hot one - missile silos and leadership protection bunkers. While the Cold War ended with the collapse of the Soviet Union in 1991 (if not before), the U.S. Intelligence Community's concern about foreign underground facilities has grown over the last two decades, particularly with respect to "rogue nations" that have discovered that hardening and concealing sensitive operations "remains an effective response to the technology advantages in intelligence and weaponry enjoyed by the United States and its allies" (Document 30). In 1999, a Defense Intelligence Agency assessment of the threat for the following twenty years stated that "The proliferation of underground facilities (UGFs) in recent years has emerged as one of the most difficult challenges facing the U.S. Intelligence Community and is projected to become even more of a problem over the next two decades."3

The concern about underground facilities (or "hard and buried" targets) is evident in the establishment of a number components in various intelligence and defense agencies. The National Reconnaissance Office has a Hard and Buried Targets Working Group (Document 29 and Document 31), while the National Geospatial Intelligence Agency, had (as of 2005) an Information and Underground Issues Division in its analysis directorate, and by 2008 the Defense Threat Reduction Agency had Hard Target Research and Analysis Center.4

But the most significant indication of the concern about underground facilities was the establishment, in 1997, of the Underground Facility Analysis Center (UFAC), which while subordinate to DIA also relies on participation from a number of other intelligence agencies — including the Central Intelligence Agency (CIA), National Security Agency (NSA), U.S. Strategic Command Joint Intelligence Operations Center, and the Air Force Technical Applications Center (AFTAC) — as well as the Defense Threat Reduction Agency (DTRA) and the U.S. Geological Survey (USGS). When it was established, UFAC had a staff of 20; by 2009 that number had grown to 240.5

The underground facilities that have been and are of concern to the U.S. Intelligence Community have an assortment of purposes. One is covert concealment and transportation, the most prominent example being the tunnels constructed under the Demilitarized Zone between North and South Korea to allow North Korean troops to be infiltrated into the South. According to independent experts, 12 levels of underground tunnels also lie beneath the Russian capital, the largest being an underground subway system reserved for high-ranking officials.6

A second type of underground facility are those employed for fuel and food storage. By 1976, according to a memo (Document 11) from the director of the Defense Intelligence Agency to the secretary of defense, the Soviet Union had either developed or was in the process of developing underground grain storage depots. In late 2008 or early 2009, North Korea reportedly built an underground fueling facility at the Musudan-ni missile complex on the nation's northeastern coast. According to the report, the objective of constructing the facility was to make it more difficult for reconnaissance satellites to detect signs that a missile was being prepared for launch.7

As noted above, the construction of underground bunkers for leadership protection was part of both United States and Soviet nuclear strategy during the Cold War. According to various reports, the end of the Cold War did not diminish Russian interest in the upgrading of older facilities and the construction of new ones.

The Pentagon's 1988 report (Document 19) on Soviet military power also noted that "neither changes in the Soviets' leadership nor the restructuring of the strategic balance and the refinements in military doctrine that accompanied these changes have diminished their commitment to the program," and that "another round of construction on these complexes began in the early 1980s." About a decade later, reports appeared concerning new Soviet underground structures, some for leadership protection. Intelligence reports from 1997 stated that construction was nearly complete on a government relocation bunker 46 miles south of Moscow. That project, along with refurbishment efforts at other bunkers in the Moscow area, was believed to be intended to ensure "continuity of leadership during nuclear war." Another construction effort was at Yamantau Mountain, about 850 miles east of Moscow — which included the digging of a "deep underground complex" as well as construction at above-ground support areas.8

Russia is, of course, not the only nation whose underground facilities are of interest to the U.S. Intelligence Community and military. In June 1989, in the midst of the Tiananmen Square demonstrations, The New York Times quoted an intelligence official as stating that "All of the top leaders have gone underground to their bunkers." Not surprisingly, U.S. forces found vast underground complexes when they arrived in Baghdad in 2003, including a 12-room complex inside a cave. Libya also maintained underground bunkers designed to protect its leadership - or, more accurately, the Qadhafi family. One was located 40 feet underneath a mansion owned by one of Muammar Qadhafi's sons. The facility contained an operating room, medical supplies, a generator, and living quarters.9

In addition to investing heavily in underground leadership protection facilities, the Soviet Union and now Russia have devoted considerable resources to underground construction with another purpose — the preservation of command, control, and communications capabilities. In 1997, an intelligence report stated that there was ongoing construction work on a "nuclear-survivable strategic command post at Kosvinsky Mountain," about 850 miles east of Moscow. A press report characterized the facility as the Russian counterpart to the North American Defense Command's Cheyenne Mountain Operations Center. In March 2011, the director of the DIA reported (Document 58) that Russia was upgrading "massive underground facilities that provide command and control of its strategic nuclear forces."10

Cuba has also, reportedly, constructed bunkers to protect command, control, and communications capabilities. According to a press report, a circa-2000 DIA report stated that "All essential Cuban command, control, and communications sites are in hardened bunkers," and that "Many of the sites are greater than 20 meters below the surface, making some too deep to attack with conventional munitions." The Amiriyah Bunker and Shelter in Iraq was originally built as an air raid shelter during the Iran-Iraq War (1980-88), and subsequently converted into a military command and control center. In 1991, it was used as a military communications center by senior Iraqi military officials. During the Persian Gulf War of 1991, selected civilians were admitted to the top floor at night, and a number were killed when the facility was bombed on February 13, 1991.11

The practice of building underground factories for weapons production may be a precaution to ensure continued production during wartime — as Nazi Germany did in relocating A-4 (V-2) production underground. It might also be a peacetime measure undertaken to limit intelligence collection about the items being produced, for example weaponry (such as biological agents) being manufactured in violation of a treaty.

In 1966, China launched Project 816, which called for an underground plutonium production reactor and a reprocessing facility located near the village of Baotao, in the Fuling District of Chongqing Province. The effort resulted in the construction of the world's largest "man-made cave" — 104,000 square meters, the equivalent of 20 football fields. However, with the facility about 85% complete, it was scrapped in 1982. After the weapons effort was shut down, the facility was converted into a chemical-fertilizer plant. (Document 56).12

Three decades after China launched that project, Libya was involved in another such project. In April 1996, the Defense Department reported (Document 23) that the Qadhafi regime had initiated construction of "a large, underground chemical warfare plant near Tarhunah, a mountainous region about 60 kilometers [37 miles] southeast of Tripoli." The DoD report observed that "putting the facility underground masks its activities and increases its survivability in case of an attack." In late June 1996 it was reported that construction had stopped on the facility — at least that there was no activity outside the site.13

In March 2011, the director of the Defense Intelligence Agency told (Document 58) a Congressional committee that "Iran has major underground nuclear facilities at Qom and Natanz." Later that year, Iran apparently moved uranium hexaflouride to the Fordow Fuel Enrichment Plant near Qom, in preparation to begin enrichment operations. Then, in January 2012 diplomats confirmed a report that Iran had commenced uranium enrichment at Fordow, and stated that 348 centrifuges were in operation, in two cascades.14

In addition to weapons production and storage, underground facilities may also be used to protect operational weapons sites - that is, sites with aircraft, missiles, or communications equipment that are ready for immediate use. A 1972 national intelligence estimate (Document 8) noted the underground facilities associated with Chinese air bases, which could be employed to hide operations-ready aircraft. A 1982 imagery analysis report (Document 15) focused on retractable radio-relay antennas that could be withdrawn into a concrete area underground.

In 1984, it was reported that North Korea also protected radars and missiles in underground facilities, popping up for action when needed. By 2002, North Korea maintained underground hangars at Puckch'ang Air Base, 34 miles northeast of Pyonyang along the Taedong River.15

In June 2011, Iran unveiled underground missile silos, which state television claimed held medium- and long-range missiles. The television report showed footage of an underground launching pad for what was identified as a Shahab-3 missile. Previously, Western news organizations had reported evidence, albeit sketchy, of Iranian missile silos near Tabriz and Khorramabad in northwest Iran.16

Exactly how many facilities around the world fall into each category is not clear , particularly not at the unclassified level. But a 2001 report to Congress (Document 30) noted the Intelligence Community's suspicion that there were over 10,000 potential hard and buried targets and that number would increase over the next decade.

U.S. intelligence requirements with respect to monitoring underground facilities can be divided into four basic categories. The first is verifying the existence of such a facility at a specific location, hints of which may come from intelligence sources or claims that may emanate from defectors. A second requirement is determining the facility's mission — whether it be leadership protection, weapons production, weapons storage or something else. The third requirement is the development of specific intelligence concerning the facility — including its physical layout and size, the number of personnel, the equipment present, and its capability and/or output — whether that be the number of troops that can pass through a tunnel, the number of weapons stored, or the facility's ability to produce enriched uranium or a biological agent. The intelligence developed concerning those requirements can be employed to assess foreign capabilities, monitor treaty compliance, as well as plan or conduct military operations.

Additional data requirements exist when the facility is considered a potential target. The information required includes the natural protection offered by the surface under which the facility has been constructed(e.g. its geology), the depth at which the facility exists, and the extent to which the facility has been hardened (and with what material).

The effort to gather such intelligence involves a variety of collection, analysis, and processing techniques. Overhead imagery, including electro-optical, radar, and infrared imagery, can spot construction in progress, allow estimation of the amount of material that has been dug out of the ground, or identify entrances leading underground. Overhead photography identified extensive underground construction in Cuba in 1966 (Document 4), a possible alternate military command center in the Wuhan Military Region of China (Document 14), and retractable radio-relay antennas in the Soviet Union and Poland in the 1980s (Document 15). The satellite imagery displayed in the 1988 edition of Soviet Military Power (Document 19) shows an entrance to a wartime underground relocation center as well as a surface support area and road/rail transfer point. Libya's work on an underground chemical agents production plant was spotted by satellite photography in the 1990s (Document 18).

Signals intelligence may provide data on the location or specifics of underground sites, such as its mission or other details about its operations. Human intelligence, including overt collection involving foreign construction crews involved in building bunkers for foreign leaders, can also contribute to knowledge about the facilities — and provide information of relevance to determining the their vulnerability to attack. Even open sources, including press and television reports, have occasionally been helpful in this regard (Document 54). The U.S. Army Intelligence and Security Command's Asian Studies Detachment has produced a number of studies of North Korean and Chinese underground facilities based on open sources.17 (Document 35, Document 44, Document 50, and Document 51)

But a key discipline in the effort directed against such targets is measurement and signature intelligence (MASINT) — which includes, but is not limited to, hyperspectral imagery, geophysical data (acoustic, seismic and electromagnetic signals), effluents, and the analysis of the collected data. The Air Force Technical Applications Center and U.S. Geological Survey, with seismic and acoustic collection capabilities, and DIA's MASINT and Technical Collection Directorate, are particularly involved in those aspects of the underground facilities intelligence effort.

The esoteric nature of the MASINT effort is illustrated by the variety of technical reports prepared in the quest to improve U.S. capabilities to gather intelligence on underground facilities. Thus, the 1999 report, Characterization of Underground Facilities (Document 20) includes sections on the magnetic detection of machinery, laser vibrometry, and the detection of heat shimmer. Similarly, a report prepared for the Air Force Office of Scientific Research, titled Time- Exposure Acoustics for Imaging Underground Structures (Document 37), contains an appendix replete with formulas and discussion of computation "by backpropagating the received signals" and "signal loss due to geometric spreading." Another report, produced by the U.S. Army Research and Development Center (Document 43) refers to signals extracted from simulation data that "reveal impulsive vertical ground-surface vibrations caused by the surface waves." Another effort, an Air War College paper (Document 36), discusses applying gravity gradiometry to the search for deeply buried facilities.

As noted above, intelligence collection and analysis concerning an underground facility may be partially based on the prospect of military action to destroy or significantly degrade the capabilities of a facility. Thus, the July 2001 report to Congress from the secretaries of defense and energy (Document 30) notes a variety of programs to procure weapons capable of penetrating hardened and buried targets, including the Enhanced GBU-28 bomb for the B-2 bomber and the Advanced Unitary Penetrator bomb for smaller aircraft. The previous year, another Air War College study, Deeply Buried Facilities: Implications for Military Operations (Document 28), examined the 'critical nodes' of deeply buried facilities and a number of 'neutralizing concepts' for each node — including (p. 23) 'undermine with suitcase nukes' and 'entombment' as possible means for overburdening the physical structure node. More recently, in early 2012, it was reported that the Pentagon had concluded that the 30,0000-pound Massive Ordnance Penetrator was not capable of destroying some of Iran's hardened underground facilities and that the Defense Department was seeking to make it more powerful.18

It is clear that no other nation, including Israel, can match the United States' capabilities for the collection and analysis of data on foreign underground facilities, or that other governments have an equal ability to develop weapons to destroy such facilities. Despite the close U.S.-Israeli intelligence relationship, it is not likely that the United States has fully shared its intelligence on facilities such as Qom. What intelligence on Qom or other Iranian nuclear facilities the U.S. chooses to share with Israel is likely to be influenced by the impact the U.S. believes such shared intelligence might have on Israeli decisions.



Document 1: Central Intelligence Agency, "Underground Shelter Used by KIM Il-Sung," May 9, 1951. Secret.
Source: CIA Records Search Tool.

This short report, probably based on human intelligence, provides data on an underground reinforced concrete shelter, constructed within a cave for North Korean leader Kim Il-Sung.


Document 2: Central Intelligence Agency, "Construction of a Large Underground Shelter under Zizkov Hill in Prague," March 27, 1957. Secret
Source: CIA Records Search Tool.

This report covers both the history of underground construction at Zizkov, which went back to World War II, as well as its then-current use for protecting employees of several nearby factories.


Document 3: National Photographic Interpretation Center, Memorandum for: Chief,
Defensive Systems Division, OSI, Subject: Search for Possible Underground Guided Missile Factory at Chieh Tsao Ping (North of Tai Yuan), China, May 15, 1963. Secret.

Source: CIA Records Search Tool (CREST).

This brief memo reports on the results of interpretation of overhead photography of the Tai Yuan area of China, including whether an underground missile factory could be detected.


Document 4: Central Intelligence Agency, Memorandum for Director, Central Intelligence; Director, Defense Intelligence Agency, Subject: Joint CIA-DIA Report on the Military Posture in Cuba As It Pertains to Strategic Weapons, August 17, 1966. Secret.
Source: LBJ Library.

This one-page memo focuses on "extensive underground construction" throughout Cuba, spotted by overhead photography. The memo notes the number of bunkers built or under construction, and the evidence (or lack thereof) concerning the possible use of the bunkers for storing strategic weapons.


Document 5: National Photographic Interpretation Center, "Underground Aircraft Dispersal, Bihac Airfield, Yugoslavia," June 17, 1968. Top Secret RUFF.
Source: CIA Records Search Tool.

This report notes the identification, based on satellite imagery, of the underground dispersal of aircraft at a Yugoslavian airfield. In addition to discussing the implications of the satellite imagery, it also provides relevant data drawn from other sources ('collateral') — including human intelligence.


Document 6: National Photographic Interpretation Center, PIR-016/71, Hardened
Central-Command-Associated Facilities Near Moscow, April 1971. Top Secret.

Source: CREST.

This photographic interpretation report describes seven hardened central-command-associated facilities in the Moscow area. The report includes references to several subsurface, hardened antennas.


Document 7: Defense Intelligence Agency, Soviet and People's Republic of China Nuclear Weapons Employment Policy and Strategy, March 1972. Top Secret. (Extract)
Source: Freedom of Information Act Request.

Annex A of this report focuses on PRC force development and deployment, and contains a brief discussion (on p. II-A-5) of China's construction — beginning no later than 1963 — of underground facilities at a number of naval bases.


Document 8: Director of Central Intelligence, NIE 13-3-72, China's Military Policy and General Purpose Forces, July 20, 1972. Top Secret. (Extract)
Source: CIA Electronic Reading Room (www.cia.gov).

In its discussion of the Chinese air force this estimate notes "a rapid growth of underground facilities near [Chinese] airfields" and that the facilities represent an "important feature of the Chinese program to build air installations." It goes on to estimate the number of airfields with underground facilities and the number of fighters they can accommodate. The estimate also discusses the advantages and disadvantages of the facilities.


Document 9: National Photographic Interpretation Center, PIR-057/72, Hardened Communications and Bunkered Facilities in Eastern Europe, January 1973. Top Secret.
Source: CREST.

This report is described as "the first in a series of reports on hardened communications and bunkered electronic facilities in Eastern Europe and the USSR" — although it focuses only on East European facilities.  Among the references to subsurface facilities is one to "a hardened control center in a cave." (p.12).


Document 10: National Photographic Interpretation Center, PIR-006/74, Hardened Communications and Bunkered Facilities in Eastern Europe, February 1974. Top Secret.  
Source: CREST.

This is the follow-up to the January 1973 report (Document 9) on certain hardened facilities in Eastern Europe. As with that report, it includes references to six command and control facilities in Poland consisting of a "long, rectangular, partially underground, earth-covered bunker." (p.4).


Document 11: Lt. Gen. Samuel V. Wilson, Director, Defense Intelligence Agency, Memorandum for the Secretary of Defense, Subject: Soviet Grain Consumption and Imports, June 25, 1976. Confidential.
Source: The Rumsfeld Papers (www.rumsfeld.com)

This brief memo references a Defense Intelligence Agency briefing on Soviet underground grain storage facilities.


Document 12: National Photographic Interpretation Center, Central Intelligence Agency, Underground Berthing Facilities in North Korea, March 1, 1978. Secret.
Source: CIA Records Search Tool.

This slide identifies the location of North Korean underground berthing facilities.


Document 13: J.F. Vesecky, W.A. Nierenberg, A.M. Despan, SRI International, JSR-79-11, Tunnel Detection, April 1, 1980. Unclassified.
Source: Federation of American Scientists (http://www.fas.org)

This technical study, conducted for the Department of Defense's scientific advisory group, JASON, focuses on the possible use of seismic and electromagnetic waves in detecting tunnels.


Document 14: National Photographic Interpretation Center, CIA. Possible Alternate Military Command Center, Wuhan Military Region, China, November 1980. Top Secret.
Source: CIA Records Search Tool.

This imagery analysis report, which apparently also uses information from communications intelligence, notes the discovery of a possible alternate military command center in eastern China, about 600 miles from Beijing. It discusses the underground complex as well as communications facilities.


Document 15: National Photographic Interpretation Center, Central Intelligence Agency, IAR-0039/82, Retractable Hardened Radio-Relay Antennas in the USSR and Poland, May 1982. Secret/WNINTEL.
Source: CIA Records Search Tool.

This imagery analysis report focuses on retractable radio-relay antennas that had been identified in the Soviet Union and Poland through satellite photography. The report notes that the antennas are mast-mounted "and the masts apparently can be retracted into a shaft set in an underground concrete housing."


Document 16: Defense Intelligence Agency, USSR: Wartime Management and Relocation Practices in the Union Republics, May 1983. Secret.
Source: DIA Freedom of Information Act Release.

This study begins with an overview of the 15 union republics, and the wartime management system.  The bulk of the study consists of the appendices examining wartime management and relocation practices in the republics — and includes a reference to an Estonian SSR underground facility and cable. (p. 28).  


Document 17: Director of Central Intelligence, IIM 83-10005JX, Soviet Wartime Management: The Role of Civil Defense in Leadership Continuity, December 1983. Top Secret.
Source: CIA Electronic Reading Room (www.cia.gov).

This interagency intelligence memorandum focuses on various aspects of the role of civil defense in the continuity of leadership in the Soviet Union in the event of war. One part of the memorandum (Chapter IV) discusses the assorted types of leadership protection and relocation facilities — which include underground structures. Among the facilities examined in the chapter are those at Sharapovo andChekhov. The authors observe that "the deep underground facilities at these complexes for the National Command Authority would present a difficult target problem." They also note that construction on another complex about 400 miles from Moscow, believed to be an alternate national command facility, was continuing.


Document 18: Central Intelligence Agency, Soviet Civil Defense: Medical Planning for Post Attack Recovery, July 1984. Secret.
Source: CIA Records Search Tool.

This study of Soviet medical planning for a post-nuclear attack environment includes a discussion (pp. 10,12) of underground medical facilities, which comprise both "modestly equipped dispensaries" as well as "extensive underground facilities." It also discusses different groups to be served by those facilities - including leadership and nearby civilian populations after evacuation.


Document 19: Department of Defense, Soviet Military Power: An Assessment of the Threat 1988 (Washington, D.C.: U.S. Government Printing Office, 1988). Unclassified. (Extract)
Source: Department of Defense.

The U.S. interest in and concern about Soviet underground leadership protection facilities was evident in some issues of the Defense Department's annual report, on Soviet military forces prepared, during the Ronald Reagan and George H.W. Bush administrations. The 1988 edition contained a discussion of those facilities, an annotated satellite photograph of a relocation facility, and a artist's depiction of both the outside and inside of such a facility.


Document 20: Department of Defense, Military Forces in Transition, 1991. (Washington, D.C.: U.S Government Printing Office, 1991). Unclassified (Extract)
Source: Department of Defense.

This, the last Department of Defense report on Soviet military power, contains a briefer treatment of Moscow's deep underground facilities, using the same artist's depiction as employed in the 1988 report (Document 19). It notes a Soviet press report about "the presence of an enormous underground leadership bunker adjacent to Moscow State University."


Document 21: Bureau of Intelligence and Research, Department of State, "Underground Nuclear Facilities," December 9, 1992. Secret.
Source: Freedom of Information Act Request.

Among the topics discussed in this report by the State Department's intelligence unit on underground facilities is the possibility that if South Africa did not accurately declare the amount of highly enriched uranium it had produced it could be stored underground in South Africa.


Document 22: National Imagery and Mapping Agency, Photo Interpretation Student Handbook, Module 6, March 1996. Unclassified. (Extract)
Source: Donation.

This paper from a manual produced by the U.S. national imagery interpretation organization (today known as the National Geospatial-Intelligence Agency) contains a brief discussion that is designed to aid imagery interpreters in identifying underground facilities employed for the storage of ammunition and bombs. It also discusses the feasibility of damaging the facilities via aerial attack.


Document 23: Office of the Secretary of Defense, Proliferation: Threat and Response, April 1996. Unclassified. (Extract)
Source: Department of Defense.

Two pages from this Defense Department report on proliferation of weapons of mass destruction focus on the Libyan chemical warfare program, which initially involved production of chemical agents at the above-ground Rabta facility. After the U.S. focused international attention on that facility, Libya began construction on an underground alternative.


Document 24: Patrick M. Hughes, Director, Defense Intelligence Agency, Memorandum for the Acting Director of Central Intelligence, Subject: Community Underground Facilities Activity (CUFA) at DIA, December 31, 1996.  Secret.
Source: DIA Freedom of Information Act Release.

In this letter to Acting DCI George J. Tenet, DIA director Hughes reports on the progress in establishing a Community Underground Facilities Activity (CUFA) — which would subsequently become UFAC. (Document 40).


Document 25: Director of Central Intelligence, FY 1998-1999 Congressional Budget Justification, Volume IV: National Reconnaissance Program, February 1997. Secret. (Extract)
Source: Federation of American Scientists (http://www.fas.org).

This page from the budget justification for the National Reconnaissance Program notes the challenges posed by underground facilities.


Document 26: JASON, JSR-97-155, Characterization of Underground Facilities, April 12, 1999. Unclassified.
Source: Federation of American Scientists (http://www.fas.org).

This technical study, produced by the DOD's JASON advisory group, examines a number of technical approaches to the characterization of underground facilities — including seismic/vibration sensing, imagery and change detection, low-frequency electromagnetic techniques, magnetic detection of machinery, detection of power lines, and low frequency electromagnetic techniques. It also examines the differences in characterizing covert and overt facilities, and looks at possible areas for future research and development.


Document 27: Department of Defense, Joint Warfighting Science & Technology Plan, February 2000. Unclassified. (Extract)
Source: www.wslfweb.org.

This chapter of the joint warfighting science and technology plan is focused at least as much on the requirements for destroying or neutralizing underground targets as on the intelligence problem. It notes the differences among underground targets with respect to a number of factors, identifies the "core capabilities" (e.g., detect, characterize) that are needed to destroy or neutralize such targets, and the functional capabilities required (eighteen in all — from sensors to decision process analysis and assessment).


Document 28: Lt. Col. Eric M. Sepp, Air War College Center for Strategy and Technology, Occasional Paper No. 14, Deeply Buried Facilities: Implications for Military Operations, May 2000. Unclassified.
Source: Air War College.

This author states that "the existence of deeply buried [u]nderground facilities has emerged as one of the more difficult challenges to confront U.S. military forces in the twenty-first century." The paper focuses on two intelligence issues — locating and analyzing deeply buried facilities — as well as neutralizing such facilities.


Document 29: National Reconnaissance Office, Hard and Deeply Buried Target (HDBT) Working Group Charter, Third Draft, August 2000. Secret/Noforn.
Source: NRO Freedom of Information Act Release.

This draft of the charter for the NRO's hard and deeply buried target working group, provides an introduction and statement of purpose for the group.  It defines its membership, states its responsibilities and functions, and provides administrative details and definitions.


Document 30: Secretary of Defense and Secretary of Energy, Report to Congress on the Defeat of Hard and Deeply Buried Targets, July 2001. Unclassified.
Source: Federation of American Scientists (http://www.fas.org).

This report was mandated by the National Defense Authorization Act for the 2001 fiscal year. It provides an introduction to the topic, a description of accomplishments, requirements, relevant programs, and the role of science and technology in meeting future threats.


Document 31: National Reconnaissance Office, Hard and Deeply Buried Target (HDBT) Working Group Charter, Second Draft, October 2001. Secret/Noforn.
Source: NRO Freedom of Information Act Release.

Although labeled as a second draft, this document is dated October 2001, in contrast to the third draft (Document 29) dated August 2000. This draft provides a synopsis (including discussion of the problem, requirement, and purpose), the authority for the group's creation, details on membership and administration, a statement of the group's function, and a delineation of its responsibilities.


Document 32: Steve Buchsbaum and Dan Cress, Special Projects Office, Defense Advanced Research Projects Agency, "A Program to Counter Underground Facilities," 2002. Unclassified.
Source: Defense Advanced Research Projects Agency (www.darpa.mil).

This short paper describes DARPA work on countering underground facilities. It delineates program objectives and notes that the DARPA program has focused on two primary approaches for characterizing underground facilities — PASEM (passive, acoustic, seismic, and electromagnetic monitoring) or the use of effluents.


Document 33: Department of State, Apparatus of Lies: Saddam's Disinformation and Propaganda, 1990-2003, 2003. Unclassified. (Extract)
Source: Department of State.

Part of this State Department release focuses on an incident during the 1991 Persian Gulf war — the allied bombing of an underground bunker whose top floor had, unknown to the U.S, been used to house civilians at night. The release describes the origins of the facility, the security arrangements as of 1991, and its use for military purposes.


Document 34: Keith Payne, Office of the Assistant Secretary of Defense for International Security Policy, For: Larry Di Rita, Subject: Secretary's Response to Rep. Tauscher before the HASC, 5 Feb., n.d. (circa Feb. 2003). Unclassified.
Source: The Rumsfeld Papers (www.rumsfeld.com).

This memo, which concerns Secretary of Defense Donald Rumsfeld's response to a question posed during a House Armed Services Committee hearing concerning small nuclear weapons, notes an attempt to improve U.S. capabilities to model the ground shock created by both nuclear and conventional weapons against underground facilities.


Document 35: 500th MI Group, INSCOM, "China's Caves and Underground Facilities Used for Air Defense," February 20, 20003. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This study, produced by the Army Intelligence and Security Command's 500th Military Intelligence Group, and based on open-source data, reports on a variety of existing and planned People's Republic of China underground facilities devoted to air defense functions.


Document 36: Lt. Col. Arnold H. Streland, Air War College, Air University, Going Deep: A System Concept for Detecting Deeply Buried Facilities from Space, February 23, 2003. Unclassfied.
Source: Air War College.

This paper, in addition to providing background on the history of underground facilities and the threat they pose, examines the problem of locating those facilities and understanding their uses, and then turns to the use of space-based gravity measurement to help locate deeply buried facilities.


Document 37: I.J. Won, Alan Witten, and Steven Norton, Geophex Ltd and University of Oklahoma, Time-Exposure Acoustics for Imaging Underground Structures, June 25, 2003. Unclassified.
Source: Defense Technical Information Center.

This paper, sponsored by the Air Force Office of Scientific Research, reports on the authors' development of a "new technique for imaging underground facilities based on the passive monitoring of acoustic emissions from both stationary and moving equipment within such facilities."


Document 38: Greg Duckworth, Defense Advanced Research Projects Agency, Counter Underground Facilities, 2004. Unclassified.
Source: Defense Advanced Research Projects Agency.

This briefing identifies different varieties of underground facilities and assorted means for detecting them.


Document 39: 500th MI Group, INSCOM, "Mines and Underground Plant in Songch'on County, North Korea," July 6, 2004. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This 500th MI Group product notes that "In the early 1950s North Korea probably constructed an underground arms plant in one of the abandoned mine pits in the country," and provides background on the events leading up to construction.


Document 40: Maj. Mark Easterbrook, 'Unearthing' the Truth in Defense of Our Nation," Pathfinder, January - February 2005. Unclassified.
Source: National Geospatial-Intelligence Agency.

This article, from the National Geospatial-Intelligence Agency's unclassified magazine, describes the background and functions of the Underground Facility Analysis Center (UFAC) as well as interagency participation in the center, which is operated by DIA. It also describes the UFAC "knowledge base" and specifies the six goals "guiding UFAC development."


Document 41: Donald Rumsfeld, Secretary of Defense, to Steve Cambone Subject: Deep Earth Penetrator, February 24, 2005. For Official Use Only.
Source: The Rumsfeld Papers (www.rumsfeld.com).

This memo from the Secretary of Defense asks for information about the underground activities of "all appropriate nations" as a prelude to a meeting about a 'bunker buster' weapon.


Document 42: Michael Klumb, "Searching for Undergrounds with a High-Tech Toolkit," Pathfinder, March - April 2005. Unclassified.
Source: National Geospatial-Intelligence Agency.

This Pathfinder article focuses on the tools used to search and characterize underground facilities. Sections cover classifying urban terrain, distinguishing recurring features, the relevance of medical techniques, and the use of radar data.


Document 43: U.S. Army Engineer Research and Development Center, Seismic Propagation From Activity In Tunnels And Underground Facilities, November 1, 2006. Unclassified.
Source: Defense Technical Information Center.

As its title partially indicates, this highly technical analysis focuses on the use of seismic signals generated by mechanical activity in underground facilities — which, the authors write, "can be measured as ground vibrations at offset distances."


Document 44: 500th MI Group, INSCOM, "Underground Hangar for Chinese Naval Aviation 4th Division's Su-30 MK2 Fighters," March 8, 2004. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This document reports on an analysis, using Google Earth satellite photographs, which concluded that underground hangars for PRC Su-30 MK2 fighters had been built at Feidong airfield, in the Nanjing Military Region.


Document 45: Scott Robertson, "Collaboration Is Cornerstone of UFAC," Pathfinder, May/June 2007. Unclassified.
Source: National Geospatial-Intelligence Agency.

In addition to specifying the agencies involved in the UFAC effort, the article notes the role of the NGA element of the center, and reports on UFAC's functions as specified in its charter.


Document 46: 500th MI Group, "Chinese Navy 1st Nuclear Submarine Zhidui Has Underground Submarine Facilities," July 16, 2007. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This study, as with other 500th MI Group products is based on open sources. It provides details on the Zhidui nuclear submarine base, the submarines present at the facility, as well as underground structures and their purpose.


Document 47: 500th MI Group, INSCOM, "North Korea Researched Technology to Protect Underground Facilities from Bunker Penetrating Bombs," August 6, 2007. Unclassified.
Source: INSCOM Freedom of Information Act Release.

North Korea's research into technology designed to protect underground facilities from penetrating bombs is discussed in this report. The report provides details of research conducted at P'Yongyang University and the contents of paper authored by a North Korean researcher and titled "Calculation of the Stress Generated in the Longitudinal Direction of a Tunnel."


Document 48: 500th MI Group, "Caves and Underground Facilities Associated with China's Second Artillery Engineer Units," September 27, 2007. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This report notes the designation of the PLA organization, "Unit 96501," that is responsible for providing underground missile facility construction to China's Second Artillery — which operates China's nuclear missile force. It then reports on probable underground construction activities for "positioning of various missiles for Second Artillery missile brigades."


Document 49: 500th MI Group, "North Korea's Use of Bulk Ammonium Nitrate Explosives to Build Underground Facilities," November 9, 2007. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This report is based on three research papers published by North Korean scientists "on drift blasting of tunnels using bulk ammonium nitrate explosives" as well as one on "composition of explosion products and explosion heat."


Document 50: 500th MI Group, "North Korea Plans to Design and Build Underground Structures with Large Cross Sections," February 13, 2008. Unclassified.
Source: INSCOM Freedom of Information Act Release.
This study examines the work of several North Korean researchers, and the implications for the nation's future construction of large underground structures.


Document 51: 500th MI Group, "North Korea Deployed Underground Structures in Soft Rock Mass with Large Domed, Double Ceilings," March 12, 2008. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This report notes that North Korea filed a patent application in 2001 for "a method of constructing an underground structure in soft rock mass with a domed double ceiling with large cross sections." It speculates that such underground structures could be used for power plants or other military-related construction.


Document 52: 500th MI Group, "Korean People's Army and Korean People's Security Guards Constructed a 2,800 Meter Long Tunnel in U'Iju," March 31, 2009. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This report concerns a tunnel constructed in an unidentified mine on the Sino-Korean border. It describes the physical dimensions of the facility and its purpose.


Document 53: 500th MI Group, "Chinese People's Liberation Army Underground Depot Facilities in Yanquan City, Shanxi Province," September 16, 2009. Unclassified.
Source: INSCOM Freedom of Information Act Release.

This study notes that a weapons depot and ammunition depot in Yanquan City are equipped with underground facilities. It also describes the surrounding area as well as camouflage techniques which have been examined at the depot.


Document 54: DNI Open Source Center, "Subtitled Clips of China's Declassified Underground Nuclear Facility in Chongqing," April 23, 2010. Unclassified.
Source: Federation of American Scientists (http://www.fas.org).

This brief OSC document reports on the content of a Chinese television report on an underground facility that was originally the home of a plutonium production reactor and was converted into a chemical factory.


Document 55: Underground Facility Analysis Center, "UFAC Digs Deep to Find Covert Facilities," Communiqué, May/June 2010. Unclassified.
Source: Freedom of Information Act Request.

This short article, appeared in the Defense Intelligence Agency's unclassified magazine, and provides a description of UFAC, the role of different agencies in the center, and some of the techniques employed by the center.


Document 56: Frank Pabian, Los Alamos National Laboratory, LA-UR#10-01758, The New Geospatial Tools: Global Transparency Enhancing Safeguards Verifications, October 27, 2010. Unclassified.
Source: Center for Nonproliferation Studies, Monterey Institute for International Studies.

One portion of this briefing focuses on the use of geospatial tools (particularly imagery and geo-location) in locating an underground facility in China that had been first constructed to house a plutonium production facility.


Document 57: 500th MI Group, “Chinese People’s Liberation Army Underground Depot Facility in Guilin City, Guangxi Zhuangzu Autonomous Region,” October 28, 2010. Unclassified.
Source: INSCOM Freedom of Information Act Release.
The PLA underground depot facility discussed in this report is associated with a petroleum and oil, and lubricants depot. Among the topics examined are the facilities and equipment at the depot.


Document 58: Lt. Gen. Ronald Burgess, Jr., Director, Defense Intelligence Agency, Statement before the Committee on Armed Services, U.S. Senate, Worldwide Threat Assessment, March 10, 2011. Unclassified.
Source: Defense Intelligence Agency.

This assessment, by the DIA's director, briefly notes the role of underground facilities in protecting Iran's nuclear program (p. 14) and Russian command and control facilities (p.20). It also notes (p. 32) that employment of underground facilities represents a transnational trend.


Document 59: Office of the Secretary of Defense, Annual Report to Congress, Military and Security Developments involving the People's Republic of China, 2011, 2011. Unclassified. (Extract)
Source: Department of Defense (www.defense.gov).

This report, which focuses on a large number of components of Chinese military power, contains a brief description of the interest of the Second Artillery Corps in the employment of underground facilities and their role in Chinese nuclear strategy.


Document 60: Gunnar J. Radel, Defense Intelligence Agency, Military Geophysics, June 14, 2011. Unclassified.
Source: Incorporated Research Institutions for Seismology (www.iris.edu).

This briefing, by a staff member of the Underground Facility Analysis Center, focuses on geophysical sensing in locating underground facilities, applications (treaty monitoring, battlespace awareness, and clandestine tunnel detection), and assorted challenges (for example, terrain and man-made clutter).


Document 61: Lt. Gen. Ronald Burgess, Jr., Director, Defense Intelligence Agency, Statement before the Committee on Armed Services, U.S. Senate, Annual Threat Assessment, February 16, 2012. Unclassified.
Source: U.S. Senate Armed Services Committee.

As he did the year before, DIA Director Burgess notes Russia's massive effort to upgrade its underground command and control facilities (p. 22). In addition (pp. 26-27) he notes six countries and one terrorist group that employ underground facilities and specifies five uses of such facilities (including cover and concealment, and industrial production).


Document 62: Jim Zanolfi, Kenneth Katzman, Jeremiah Getler, and Steven A. Hildreth, Congressional Research Service, Israel: Possible Military Strike Against Iran’s Nuclear Facilities, September 28,  2012.  Unclassified.
Source: Federation of American Scientists (www.fas.org).

A portion of this analysis of a possible Israeli attack on Iran’s nuclear facilities discusses Iranian underground nuclear sites and the weapons that might be employed in an attack on them. 


1. Joby Warrick, "Iran's underground nuclear sites not immune to U.S. bunker-busters, experts say," www.washingtonpost.com, February 29, 2012; Bill Gertz, "A Tour of Syria's Chemical Weapons," Washington Free Beacon, September 28, 2012; Anthony Cordesman, "Syrian Weapons of Mass Destruction, An Overview," Center for Strategic & International Studies, June 2, 2008.

2. Michael J. Neufeld, The Rocket and the Reich: Peenemunde and the Coming of the Ballistic Missile Era (New York: Free Press, 1995), p. 202; F.H. Hinsley, E.E. Thomas, C.A.G. Simkins, and C.F.G. Ransom, British Intelligence in the Second World War, Volume 3, Part 2 (New York: Cambridge University Press, 1988), p. 571; Constance Babington-Smith, Air Spy: The Story of Photo Intelligence in World War II (New York: Harper & Brothers, 1957), pp. 192-193.

3. Defense I\ntelligence Agency, A Primer on the Future Threat, The Decades Ahead: 1999-2020, July 1999, p. 139. Portions of the Primer appear in Rowan Scarborough, Rumsfeld's War: The Untold Story of America's Anti-Terrorist Commander (Washington, D.C.: Regnery, 2004), pp. 194-223.

4. "About the Authors," Pathfinder, May/June 2005, p. 4; "Statement of Dr. James Tengelia, Director, Defense Threat Reduction Agency before the Subcommittee on Emerging Threats and Capabilities, Committee on Armed Services, United States Senate," March 12, 2008, p. 5.

5. Maj. Mark Esterbrook, "'Unearthing' the Truth in Defense of Our Nation, Pathfinder, January-February 2005, pp. 19-21; "Tunnel vision," DefenseNews (www.defensenews.com), August 1, 2009. The Air Force Technical Applications Center (AFTAC), in response to a FOIA request for a copy of any memorandum of agreement between AFTAC and UFAC refused to confirm or deny the existence of such an agreement. However, the DIA, in response to an identical request, while denying the request, stated that "A search of DIA's systems of records located one document responsive to your request." Alesia Y. William, Chief, Freedom of Information Act Staff, Defense Intelligence Agency, to Jeffrey Richelson, July 8, 2010.

6. Andrei Soldatov and Irina Borogan, The New Nobility: The Restoration of Russia's Security State and the Enduring Legacy of the KGB (New York: Public Affairs, 2010, p. 118.

7. Lt. Gen. Samuel V. Wilson, Director, Defense Intelligence Agency, Memorandum for the Secretary of Defense, Subject: Soviet Grain Consumption and Imports, June 25, 1976. Kwang- Tae Kim, Associated Press, "Report: NKorea builds underground fueling facility," February 25, 2009.

8. Department of Defense, Soviet Military Power, An Assessment of the Threat 1988, p. 60; Bill Gertz, "Moscow builds bunkers against nuclear attack," Washington Times, April 1, 1997, pp. A1, A16; Bill Gertz, Betrayal: How the Clinton Administration Undermined American Security (Washington, D.C.: Regnery, 1999), pp. 44, 231.

9. Thomas L. Friedman, "200,000 Troops Near Beijing, U.S. Says," New York Times, June 8, 1989, p. A13; Robert Tanner, "U.S. soldiers enter Saddam's tunnels," Washington Times, April 10, 2003, p. A13. Thomas Erdbrink, "Deep underground, elaborate bunkers show that Gaddafi family was ready," Washington Post, August 26, 2011, p. A8.

10. Bill Gertz, "Moscow builds bunkers against nuclear attack"; Bill Gertz, Betrayal, pp. 47, 231; Kenneth R. Timmerman, "Inside Russia's magic mountain," World Net Daily (www.wnd.com), June 6, 2000; Lt. Gen. Ronald L. Burgess, Director, Defense Intelligence Agency Statement before the Committee on Armed Services, United States Senate, World Wide Threat Assessment, March 10, 2011, p. 20.

11. Bill Gertz, "Notes from the Pentagon," December 8, 2000, http://www.gertzfilecom/InsidetheRing.html, "Cuba Bunkers," http://groups.yahoo.com/group/coldwarcomms/message/1730. U.S. Department of State , Apparatus of Lies: Saddam's Disinformation and Propaganda, 1990-2003, 2003, p. 12.

12. Frank Pabian, Los Alamos National Laboratory, LA-UR 10-04532, Using the New Geospatial Tools to Locate a Newly Revealed Underground Plutonium Production Complex in China, July 21, 2010, n.p. Open Source Center, "Subtitled Clips of China's Declassified Underground Nuclear Facility in Chongqing," April 23, 2010.

13. Barbara Starr, "Impenetrable Libyan CW plant progresses ...," Jane's Defence Weekly, April 17, 1996, p. 3; "Targeting a Buried Threat," Newsweek, April 22, 1996, p. 6; Charles Aldinger, "U.S. Rules Out Nuclear Attack on Libya Plant," Washington Post, May 8, 1996, p. A32; Bill Gertz, "Libyans stop work on chemical plant," Washington Times, June 25, 1996, p. A4; Office of the Secretary of Defense, Proliferation: Threat and Response, April 1996, p. 26.

14. Lt. Gen. Ronald L. Burgess, Jr., Director, Defense Intelligence Agency, Statement before the Committee on Armed Services, United States Senate, Worldwide Threat Assessment, March 10, 2011, p. 14; "Iran Prepares to Transport Atomic Substance to New Enrichment Facility," Global Security Newswire, (http://gsn.nti.org), October 21, 2011; George Jahn, "Iran nuclear work at bunker is confirmed," www.washingtontimes.com, January 9, 2012; David E. Sanger, "Iran Trumpets Nuclear Ability At a 2nd Plant," New York Times, January 9, 2012, pp. A1, A3.

15. Benjamin F. Schemmer, "North Korea Buries Its Aircraft, Guns, Submarines, and Radars Inside Granite," Armed Forces Journal International, August 1984, pp. 94-97. Jonas Siegel, "In harm's way," Bulletin of the Atomic Scientists, May/June 2005, pp. 34-35.

16. William J. Broad, "Iran Unveils Missile Silos As It Begins War Games," New York Times, June 28, 2011, p. A4.

17. David A. Reese, "50 Years of Excellence: ASD Forges Ahead as the Army's Premier OSINT Unit in the Pacific," Military Intelligence Professionals Bulletin, October - December 2005, pp. 27-29.

18. Adam Entous and Julian E. Barnes, "Pentagon Seeks Mightier Bomb Vs. Iran," Wall Street Journal January 28-29, 2012, pp. A1, A2.

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