Those impurities do muck up your centrifuges. It's not a problem if you want 3.5 percent enriched uranium for power plants, but if you go to 90 percent these impurities are a major problem.

We should not pour muck on ourselves.

Given another year to make enough HEU (highly enriched uranium) for a nuclear weapon and a few more months to convert the uranium into weapon components, Iran could have its first nuclear weapons in 2009.

The big problem with uranium is that there's a scarcity of supply.

Those impurities do muck up your centrifuges. It's not a problem if you want 3.5% enriched uranium for power plants, but if you go to 90% these impurities are a major problem.

A vast percentage of centrifuges have to be rejected in testing, up to 60% rejection.