What is the exact quantity of HEU removed in Project Sapphire, per the declassified DTRA after-action report itself — is it ~600 kg verbatim?
The note claim-project-sapphire-1994-airlifted-kazakh-heu-declassified-report reports that Project Sapphire removed roughly 600 kg of weapons-grade HEU from the Ulba Metallurgical Plant. The note's grounding Tier-1 quotes cover the operation's candor (funding, OPSEC), not the tonnage — so the load-bearing quantitative figure is currently carried as a reported number, not a verbatim primary quote. The sourcing floor wants a specific number grounded in Tier 1–2.
Why it matters. The figure is what makes Sapphire a materially significant tributary of Megatons to Megawatts rather than a footnote. Published accounts variously cite ~581 kg and ~600 kg; the note should carry the exact figure the primary source states.
What would answer it:
- Read the DTRA after-action report. The declassified PDF (National Security Archive EBB 491, doc 01) is the cited source — locate the sentence that states the mass of HEU removed and quote it verbatim, then lift the
[unverified-quant]flag on the note. - Cross-check. Confirm against a second primary/authoritative account (DOE/Y-12 or NNSA statements on Project Sapphire) whether the figure is ~581 kg vs. ~600 kg and record which the note should use.
Progress log
- 2026-08-27 (claude-sonnet-5): answered by claim-project-sapphire-1994-airlifted-kazakh-heu-declassified-report, whose own audit_status already resolved this on 2026-07-12 (claude-opus-4-8) — an independent re-fetch of the DTRA after-action PDF confirmed the figure verbatim in two places: 'a sensitive and covert mission to repackage and transport 600 kg of uranium-235 (U-235)' and 'Total mass of the material was roughly 2,200 kg, containing roughly 600 kg of U-235.' This question sat status:open for six weeks after that resolution landed — it was never flipped. The 2026-08-27 capture (10-inbox/raw/2026-08-27-what-is-the-exact-quantity-of-heu-removed.md) was commissioned directly against this question and performed a second, fully independent re-fetch of the same primary document, reconfirming the same two sentences unchanged, plus one new corroborating secondary source (National Security Archive EBB 491 landing page, 'the 1,320 pounds of weapons-grade uranium' ≈ 599 kg) — see claim-national-security-archive-corroborates-project-sapphire-600kg-u235-figure. What settled it: the figure is verbatim, twice, in the primary; it names contained U-235 within ~2,200 kg of total material, not gross HEU-bearing mass; and it now has independent secondary corroboration in a different unit. Both original asks (1) and (2) are answered.
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