D.1. Natanz: Fuel Enrichment Plant and Pilot Fuel Enrichment Plant
11. Fuel Enrichment Plant (FEP): There are two cascade halls at FEP: Production Hall A and Production Hall B. According to design information submitted by Iran, eight units are planned for Production Hall A, with 18 cascades in each unit. No detailed design information has yet been provided for Production Hall B.
12. As of 19 February 2012, 54 cascades were installed in three of the eight units in Production Hall A,52 of which were declared by Iran as being fed with UF6.10 Where as initially each installed cascade comprised 164 centrifuges, Iran subsequently modified 30 of the cascades to contain 174 centrifuges each.
All the centrifuges installed are IR-1 machines. As of 19 February 2012, no centrifuges had been installed in the remaining five units, although preparatory installation work had been completed in two of the units, including the placement in position of 6177 empty IR-1 centrifuge casings, and was ongoing in the other three units. As of 19 February 2012, there had been no installation work in Production Hall B.
13. The results of a physical inventory verification (PIV) carried out by the Agency at FEP confirmed the inventory on 16 October 2011 as declared by Iran, within measurement uncertainties normally associated with such a facility. Therefore, there were no consequences for safeguards arising from the seal breakage inthe feed and withdrawal area reported by the operator in April 2011.11
14. The Agency has confirmed that, as of 16 October 2011, 55 683 kg of natural UF6 had been fed into the cascades since the start of operations in February 2007, and a total of 4871 kg of UF6 enriched up to 5%U-235 had been produced. Iran has estimated that, between 17 October 2011 and 4 February 2012, it produced 580 kg of UF6 enriched up to 5% U-235, which would result in a total production of 5451 kg ofUF6 enriched up to 5% U-235 since production began in February 2007. The nuclear material at FEP (including the feed, product and tails), as well as all installed cascades and the feed and withdrawal stations,are subject to Agency containment and surveillance.12
15. Based on the results of the analysis of environmental samples taken at FEP since February 200713 and other verification activities, the Agency has concluded that the facility has operated as declared by Iran in the relevant Design Information Questionnaire (DIQ).
16. Pilot Fuel Enrichment Plant (PFEP): PFEP is a research and development (R&D) facility, and a pilot low enriched uranium (LEU) production facility, which was first brought into operation in October 2003. It has a cascade hall that can accommodate six cascades, and is divided between an area designated for the
production of LEU enriched up to 20% U-235 (Cascades 1 and 6) and an area designated for R&D (Cascades 2, 3, 4 and 5).
17. The results of a PIV carried out by the Agency at PFEP confirmed the inventory on 13 September 2011 as declared by Iran, within measurement uncertainties normally associated with such a facility. The results also show an improvement in the operator’s measurement system, in particular in relation to the determination of the level of U-235 enrichment.14
18. Production area: Iran first began feeding low enriched UF6 into Cascade 1 on 9 February 2010, for the stated purpose of producing UF6 enriched up to 20% U-235 for use in the manufacture of fuel for the Tehran Research Reactor (TRR). 15,16 Since 13 July 2010, Iran has been feeding low enriched UF6 into two interconnected cascades (Cascades 1 and 6), each of which consists of 164 IR-1 centrifuges.17
19. As previously reported,18the Agency has verified that, as of 13 September 2011, 720.8 kg of low enriched UF6 had been fed into the cascades in the production area since the process began on 9 February 2010, and that a total of 73.7 kg of UF6 enriched up to 20% U-235 had been produced. Iran has estimated that, between 14 September 2011 and 11 February 2012, a total of 164.9 kg of UF6 enriched atFEP was fed into the two interconnected cascades at PFEP and that approximately 21.7 kg of UF6 enrichedup to 20% U-235 were produced. This would result in a total production of 95.4 kg of UF6 enriched up to20% U-235 at PFEP since production began in February 2010.
20. R&D area: In the area designated for Cascades 2 and 3, Iran has been intermittently feeding natural UF6 into single machines, 10-machine cascades and 20-machine cascades of IR-1, IR-2m and IR-4centrifuges. In a letter dated 1 February 2012, Iran informed the Agency of its intention to install three newtypes of centrifuge – IR-5, IR-6 and IR-6s – as single machines in Cascade 2. As of 21 February 2012, Iran had installed 58 IR-4 centrifuges in Cascade 4, which has not been fed with UF6. Iran had also installed 164IR-2m centrifuges in Cascade 5.19 Between 9 and 12 August 201120 and from 5 November 2011 onwards,21 Iran has been intermittently feeding natural UF6 into Cascade 5.
21. Between 29 October 2011 and 11 February 2012, a total of approximately 164.4 kg of natural UF6 wasfed into centrifuges in the R&D area, but no LEU was withdrawn as the product and the tails are recombined at the end of the process.
22. Based on the results of the analysis of the environmental samples taken at PFEP22 and other verification activities, the Agency has concluded that the facility has operated as declared by Iran in the relevant DIQ.