The NUMEC affair: the bomb-grade uranium that vanished.
Hundreds of kilograms of weapons-grade uranium went unaccounted for at a small Pennsylvania plant — the largest such loss at any US commercial site. For fifteen years, across four administrations, the CIA, FBI, and half the national-security state investigated whether it had been diverted to build Israel’s atom bomb. The files are declassified now.
The spine is graded FACT: the missing material, the multi-agency investigation, the CIA’s belief that it went to Israel, Shapiro’s documented Israeli ties, the uranium traced near Dimona. The central question — whether it was actually diverted or simply lost to contamination — we grade SOME SMOKE: officially suspected, a CIA case Carter’s own staff called “persuasive, though not conclusive,” and never proven. This is not a conspiracy theory. It is an unresolved government investigation.
What this page argues
The Nuclear Materials and Equipment Corporation (NUMEC) ran a highly-enriched-uranium plant in Apollo, Pennsylvania, that processed bomb-grade fuel for the US Navy. Beginning with a 1965 AEC inventory, the government found a staggering shortfall: by the government’s own later records, roughly 269 kilograms of weapons-grade U-235 went unaccounted for before 1968 (and more after) — the single largest such loss at any US commercial site. NUMEC paid for the material and disputed the math, attributing the gap to ordinary processing losses. The government wasn’t sure.
For roughly fifteen years, across four presidential administrations, an extraordinary roster of agencies investigated whether the uranium had been diverted to Israel’s nuclear-weapons program: the AEC (later NRC), the FBI, the Justice Department, the CIA, the Joint Committee on Atomic Energy, the GAO, the NSC, the DIA, and two House committees. They never fully accounted for it. Some in senior positions firmly believed it had gone to Israel: in February 1976 the CIA briefed the NRC that it believed the HEU went there, and when President-elect Carter was briefed, his National Security Advisor’s staff concluded, “The CIA case is persuasive, though not conclusive.”
The circumstantial trail is real: NUMEC’s president, Zalman Shapiro, was a committed Zionist with documented business and government contacts in Israel, including with figures the FBI tied to Israeli scientific-intelligence collection; the Israeli operative Rafi Eitan — later revealed as the handler of spy Jonathan Pollard — visited the Apollo plant; and a 1968 CIA finding reportedly traced US-origin HEU to the environs of Israel’s Dimona reactor, a fact former AEC chairman Glenn Seaborg recorded in his 1978 diary.
And yet it was never proven. No one was charged. Seymour Hersh, the NRC’s later contamination findings, investigator Carl Duckett, and Seaborg himself concluded (or strongly suspected) the uranium was lost to the plant’s air, water, ducts, and floors, not smuggled abroad. So we grade the diversion SOME SMOKE — a serious, officially-investigated suspicion, not an established fact — and grade the documented record around it FACT. The reason it belongs here at all: what gets waved away today as an antisemitic “conspiracy theory” was, for fifteen years, a formal US intelligence investigation. The files exist.
We are not asserting as proven fact that Zalman Shapiro or NUMEC diverted uranium to Israel. No court found it, no agency conclusively established it, and credible investigators attribute the loss to contamination and processing. We grade the diversion SOME SMOKE precisely because it is documented suspicion, not proof, and we carry the exculpatory case in full.
We are not trafficking in a “dual loyalty” trope about Jewish Americans. The point is narrow and specific: a real quantity of bomb-grade uranium is unaccounted for, and the US government itself — not a fringe blog — spent fifteen years and four administrations investigating whether it reached Israel. That is history, graded to what the declassified record supports.
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The NUMEC affair.
Hundreds of kilos of weapons-grade uranium vanished from a small Pennsylvania plant — the largest such loss at any US commercial site. For 15 years, across four administrations, the CIA and FBI investigated whether it built Israel's bomb. The files are declassified now.
The record, claim by claim.
Hundreds of kilograms of bomb-grade uranium went unaccounted for at NUMEC — the largest such loss at any US commercial site.
FACTA 1965 Atomic Energy Commission inventory of government-owned HEU leased to NUMEC's Apollo, Pennsylvania plant revealed a major shortfall. After extensive efforts to account for processing losses, the AEC confirmed in 1966 that 178 kilograms of U-235 (as highly enriched uranium) were missing; within a few years the figure grew to 269 kg. Later Department of Energy records show NUMEC had the largest HEU inventory loss of any US commercial site — 269 kg before 1968, and roughly 76 kg more afterward. NUMEC paid for the missing material but disputed the AEC's calculations, arguing the gap was ordinary processing loss.
For ~15 years and four administrations, a dozen US agencies investigated whether it was diverted to Israel — and never fully accounted for it.
FACTFrom 1965 into the early 1980s, the AEC (later the NRC), FBI, Justice Department, CIA, the Joint Committee on Atomic Energy, the GAO, the NSC, the DIA, and two House committees all investigated the missing NUMEC uranium and whether it had reached Israel. None fully accounted for it. The FBI investigated Shapiro for years, including with warrantless wiretaps; the Justice Department chose not to prosecute. In 2009, at the request of Shapiro's lawyer, Sen. Arlen Specter asked the NRC to clear him; the NRC declined, stating it 'found no documents that provided specific evidence that the diversion of nuclear materials occurred' — while pointedly not clearing him either. A 2010-declassified GAO study said a 'timely, concerted effort' by the agencies 'would have greatly aided and possibly solved the NUMEC diversion questions, if they desired to do so.'
The CIA believed the uranium went to Israel — a case Carter's own staff called 'persuasive, though not conclusive.'
FACTThis is the heart of the official suspicion. In February 1976, the CIA briefed senior NRC staff that it believed the missing HEU had been diverted to Israel; the NRC informed the White House, and President-elect Carter was briefed. Carter asked his National Security Advisor for an assessment, whose staff concluded: 'The CIA case is persuasive, though not conclusive.' Separately, a 1968 CIA finding reportedly traced HEU of US origin to the environs of Israel's Dimona reactor — a fact former AEC chairman Glenn Seaborg recorded in his diary in June 1978, and which 2015-declassified CIA documents appear to support. These are the assessments of the US intelligence community, on the record.
“The CIA case is persuasive, though not conclusive.”
CIA vs. FBI: the agency pushed the Bureau to investigate — and the case was quietly closed.
FACTThe inter-agency record, now declassified, is its own story — and a March 11, 1976 CIA memorandum from Deputy Director for Science and Technology Carl Duckett to the Director of Central Intelligence lays out the chronology. On April 2, 1968, CIA Director Richard Helms wrote Attorney General Ramsey Clark, urging that the FBI 'initiate a discreet intelligence investigation of all source nature of Dr. Shapiro in order to establish the nature and extent of his relationship with the Government of Israel,' because it was 'critical … to establish whether or not the Israelis now have the capability of fabricating nuclear weapons' (declassified via ISCAP in 2014); the Attorney General directed the FBI to investigate on April 23, 1968. But by September 3, 1969, per the CIA memo, Hoover reported that the AEC's security director had asked Shapiro only whether he had 'passed classified information to any foreign government' — Shapiro said no — and, in the CIA's own dry words, 'Apparently no mention was made of the passage of nuclear material to a foreign government.' On a case about missing bomb-grade uranium and Israel, the Bureau never asked the central question — then Hoover discontinued the active investigation. When Helms pushed again in October 1969, urging audio surveillance because Shapiro 'planned to emigrate to Israel,' and asked that the matter be taken to the Attorney General, the memo records flatly: 'This was not done.' It ends: 'There was no further FBI reporting on the case after that.' The pattern was not isolated: CIA Tel Aviv station chief John Hadden later called NUMEC 'an Israeli operation from the beginning,' and days after the Helms memo — September 10, 1968 — NUMEC hosted Avraham Hermoni, a coordinator of Israel's clandestine nuclear-weapons program, and three undercover Israeli intelligence operatives, billed to the AEC as 'energy specialists.' The case was reopened in 1976 as 'DIVERT' — mandated to uncover 'any attempt by anyone in the executive branch to prevent or impede an investigation' — and placed in 'closed status' on January 23, 1981. The counterintelligence agency believed there was something to find and pressed for it; the Bureau never asked the key question, and the case was shut without ever being resolved.
“I urge that the Federal Bureau of Investigation be called upon to initiate a discreet intelligence investigation … of Dr. Shapiro in order to establish the nature and extent of his relationship with the Government of Israel.”
- CIA memorandum, Carl E. Duckett (Deputy Director for Science & Technology) to the Director of Central Intelligence, 'Nuclear Materials and Equipment Corporation (NUMEC),' March 11, 1976 (ISCAP-declassified; Gerald R. Ford Library) — the chronology and the quoted lines ('Apparently no mention was made…,' 'This was not done,' 'There was no further FBI reporting…')
- IRmep / The Israel Lobby — the April 2, 1968 Helms-to-Ramsey-Clark memo (ISCAP-declassified 2014), the Hadden quote, the Hermoni visit, and the 1976 'DIVERT' reopening
Shapiro had documented Israeli ties — and a known Israeli operative visited the plant.
FACTZalman Shapiro — NUMEC's president, a chemist who had helped develop the Nautilus submarine reactor — was a committed Zionist with documented business and government contacts in Israel, including a contract to build nuclear-powered generators there. Declassified FBI reports indicate he collaborated with Israeli officials, including figures the Bureau tied to Israel's scientific-intelligence collection effort (later known as LAKAM). And the Israeli operative Rafi Eitan — subsequently revealed as an Israeli spy and the handler of convicted spy Jonathan Pollard — visited the Apollo plant; analyst Anthony Cordesman told UPI in 1986, 'There is no conceivable reason for Eitan to have gone [there] but for the nuclear material.' These are documented associations, not proof of a crime — but they are why the investigation existed.
Whether the uranium was actually diverted to Israel — never proven, and seriously disputed.
SOME SMOKEThis is the unresolved core, and we grade it honestly. On the suspicion side: the persuasive-but-inconclusive CIA case, the Dimona trace, Eitan's visit, and a 2009-released FBI statement from a former NUMEC employee who said he saw armed strangers loading HEU canisters onto a truck in early 1965, with a manifest for a ship on the Zim-Israel line. On the exculpatory side: Seymour Hersh, in 'The Samson Option' (1991), concluded Shapiro diverted nothing — the material 'ended up in the air and water of the city of Apollo as well as in the ducts, tubes, and floors of the NUMEC plant'; the NRC attributed large later losses (after Shapiro left) to 'previously unidentified loss mechanisms' like contamination and scrubber systems; investigator Carl Duckett said 'I know of nothing at all to indicate that Shapiro was guilty'; and former AEC chairman Glenn Seaborg called the charges against him 'unjust.' The senior officials themselves split, which is the honest heart of it: CIA station chief John Hadden called NUMEC 'an Israeli operation from the beginning,' and Carl Duckett is quoted affirming diversion in some declassified accounts even as Hersh quotes him doubting Shapiro's guilt — the same investigator, cited on both sides. A real quantity of bomb-grade uranium is missing and the US government took the diversion theory seriously for fifteen years — but it was never established. That is textbook SOME SMOKE.
The two honest readings — and why the answer still matters either way.
The diversion case: a huge, unexplained HEU deficit; a Zionist plant president with Israeli intelligence-adjacent contacts; a known Mossad operative on the loading dock; a CIA that believed it, briefed the White House, and reportedly traced US-origin uranium to Dimona; and a whistleblower account of canisters bound for an Israeli ship. Serious people in serious positions concluded Israel got the material.
The loss case: HEU plants of that era genuinely bled material into equipment, ducts, flooring, and scrubbers — and the NRC documented exactly that for large losses at the same plant after Shapiro was gone. Hersh, Duckett, and Seaborg — not apologists — concluded the uranium was lost, not smuggled, and that the case against Shapiro was never made. No charges were ever filed. Even the CIA’s own 1968 Helms memo conceded that in 1965 the AEC reported “no evidence had been found to support the possibility of diversion, and that other information did exist to reduce such a possibility.”
Why it matters either way: if it was diverted, the US government watched weapons-grade uranium walk out the door to a foreign nuclear program and buried it. If it was lost, the government still couldn’t account for enough bomb-grade material to build several warheads, at the largest-loss site in the country. Both readings are an indictment — of security, of oversight, or of candor. We land on SOME SMOKE for the diversion, and let the reader weigh the two cases the declassified record actually supports.
What gets called “conspiracy” was an official investigation.
The reason this belongs in the Israeli Influence hub isn’t that it proves a theft — it doesn’t, and we say so. It’s that the question of whether the US quietly helped, or failed to stop, Israel’s acquisition of nuclear material is routinely dismissed as an antisemitic conspiracy theory — when the CIA, FBI, AEC, and four presidential administrations treated it as a live counterintelligence problem for fifteen years, and much of their work is now declassified. “Conspiracy” is what an official investigation gets called once it’s politically inconvenient to remember it happened.
It sits alongside JFK’s standoff with Israel over Dimona and the Palestine Laboratory: the documented, unromantic history of how Israel’s bomb and its defense-tech edge were built partly with American material, money, and tolerance. The value of grading it honestly — FACT for the record, SOME SMOKE for the diversion — is that it can’t be waved away as a smear. It’s a government file with the black bars coming off.
Questions worth taking seriously
Was the uranium proven to have gone to Israel?
Isn't raising this just antisemitism?
If it was just contamination, why is this still a story?
If you are named on this page
If you are named on this page, or are a party materially affected by the claims made here, and you wish to respond, correct the record, or add context, use the Contact page. Responses are published verbatim alongside the original claim, with the sender identified and the date of receipt. The channel stays open for the life of the page.
This site aggregates and grades a record that other outlets and primary sources have already put on the record. Every FACT-graded claim above is sourced to court filings, government reports, sworn whistleblower disclosures, published investigative journalism, or named-source statements. The citations are the accountability mechanism; this section is how you get on the record too.
The declassified record, and the case against diversion.
Every claim on this page grades to one of FACT · PROBABLY TRUE · SOME SMOKE · PURE SPECULATION · FALSE / MISLEADING. The missing material, the multi-agency investigation, the CIA’s belief and the Carter-staff assessment, Shapiro’s documented Israeli ties, and the Dimona trace are graded FACT from declassified documents and mainstream reporting. Whether the uranium was actually diverted is graded SOME SMOKE: officially suspected, never proven, and credibly disputed.
- National Security Archive (with Roger J. Mattson) — “The NUMEC Affair,” the declassified document collection
- Wikipedia — “Apollo affair” (the DOE loss record, the CIA/Carter assessments, Hersh, Duckett, Seaborg, Eitan)
- Federation of American Scientists — the declassified GAO report on the 1965 NUMEC affair
- IRmep / The Israel Lobby — the NUMEC FBI and CIA files and the 2009 former-employee statement
- Seymour Hersh, The Samson Option (1991), and Glenn T. Seaborg, The Atomic Energy Commission under Nixon (1993) — the case that the loss was contamination, not diversion
Full method: Methodology. Home hub: Israeli Influence.
Last updated September 18, 2026. The unaccounted-for HEU (269 kg before 1968 per DOE, the largest loss at any US commercial site), the 1965– early-1980s multi-agency investigation across four administrations, the CIA’s belief that the material went to Israel (and the Carter-staff “persuasive, though not conclusive” assessment), Zalman Shapiro’s documented Israeli ties, Rafi Eitan’s visit, and the 1968 Dimona trace (Seaborg’s diary; 2015 CIA documents) are graded FACT from the declassified record. Whether the uranium was actually diverted to Israel is graded SOME SMOKE — officially suspected, never proven, and credibly disputed by Hersh, Duckett, and Seaborg. If a link 404s or a detail is wrong, tell us and we will fix it publicly.