During the production of uranium mining and metallurgy, some waste ores and mill tailings with radioactive elements are produced, which may do harm to natural environment and people.

The letter said the plant would not enrich uranium beyond the 5% level suitable for civilian energy production. That would be substantially below the threshold of 90% or more needed for a weapon.

Iran's conversion of uranium, laser enrichment and fuel production programs have already been placed under the routine safeguards monitoring.