Nuclear talks resume Wednesday between Iran and world powers after the last round stalled over issues that include Iran's planned heavy water reactor and the levels of uranium enrichment. Iran later agreed to provide U.N. nuclear inspectors with greater information and access, but it's uncertain whether the concessions will be enough to push envoys in Geneva closer to a deal. Iran seeks a rollback in U.S.-led economic sanctions, while the West is pressing it to curb its uranium enrichment the process to make nuclear fuel. In the past decade, Iran's nuclear program has advanced on many fronts and more facilities are planned.
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RAISED AT TALKS
ARAK HEAVY WATER REACTOR: Such reactors can run on non-enriched uranium as fuel and uses a molecular variant of water as a coolant. Heavy water reactors also produce more plutonium byproducts than conventional reactors. Plutonium can be used in nuclear weapons. Iran began work on its facility in 2004 in Arak, about 250 kilometers (150 miles) southwest of Tehran. U.N. nuclear inspectors have visited the site, but have been promised wider access under the latest accord between Iran and the U.N's International Atomic Energy Agency, or IAEA. The reactor is nearing completion, but no specific date has been announced to begin operations. Iran says the reactor will be used to produce isotopes for medical and industrial uses. The country also does not possess the technology needed to reprocess the plutonium byproducts for possible use in nuclear arms.
ENRICHMENT SITES: Iran has two main uranium enrichment facilities. The oldest and largest in Natanz, about 260 kilometers (160 miles) southeast of Tehran is largely built underground and is surrounded by anti-aircraft batteries. Uranium enrichment began in 2006. Another site is known as Fordo, which is built into a mountainside south of Tehran. Its construction was kept secret by Iran until it was disclosed in September 2009 in a pre-emptive move before its existence was revealed by Western intelligence agencies. The area is heavily protected by the Revolutionary Guard. U.N. nuclear inspectors have visited both sides and have installed round-the-clock monitoring systems.