UN Security Council
2015

calandria will be made inoperable by filling any openings in the calandria with concrete such that the IAEA can verify that it will not be usable for a future nuclear application. In redesigning and reconstructing of the modernized Arak heavy water research reactor, Iran will maximise the use of existing infrastructure already installed at the current Arak research reactor. 4. Iran will take the leadership role as the owner and as the project manager, and have responsibility for overall implementation of the Arak modernisation project, with E3/EU+3 participants assuming responsibilities regarding the modernisation of the Arak reactor as described in this Annex. A Working Group composed of E3/EU+3 participants will be established to facilitate the redesigning and rebuilding of the reactor. An international partnership composed of Iran and the Working Group would implement the Arak modernisation project. The Working Group could be enlarged to include other countries by consensus of the participants of the Working Group and Iran. E3/EU+3 participants and Iran will conclude an official document expressing their strong commitments to the Arak modernisation project in advance of