CARLSBAD, N.M. (AP) — The federal government's underground nuclear waste repository in New Mexico has received its 12,500th shipment since operations began two decades ago.

The U.S. Energy Department made the announcement Tuesday, saying the shipment arrived at the Waste Isolation Pilot Plant just before midnight on June 27.

The shipment originated at Idaho National Laboratory.

The repository is licensed to take Cold War-era waste generated by decades of bomb-making and defense-related nuclear research. The waste includes gloves, clothing, tools and other materials contaminated with radioactive elements.

In all, more than 178,500 containers have been trucked over 14.9 million miles (24 million kilometers) to the repository from sites around the country since 1999. The waste is entombed in disposal rooms carved out of an ancient salt formation about half a mile (0.8 kilometers) down.

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