Photos: Stanford's X-ray vision

In this radiation-shielded "rabbit hutch," scientists handle materials from nuclear waste sites. Using X-rays to determine the level of contamination in the samples enables them to suggest precision cleanup methods.

Such techniques measured plutonium in the topsoil around the former Rocky Flats Nuclear Weapons Plant near Denver, which led to removing the dirt to prevent it from traveling via wind and rain. Scientists have used similar methods to evaluate highly radioactive cesium and strontium in the ground around Chernobyl.

In another potential scenario, the use of such X-rays to examine plant life at a waste site might show, say, poisons within the leaves but not the roots. That would allow, for instance, the plants to remain safely in the ground as long as the leaves were regularly removed.