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How the Sample
Management Facility Works

The Sample Management Facility stores rock and other geologic samples for the Yucca Mountain Project. Most of these samples are rock cores and cuttings taken from holes drilled into Yucca Mountain. Samples from deep underground tunnels also are stored here.

To ensure that rock samples can be traced to their origins, workers at this facility, keep complete records for each sample— where it came from, who handled it, and the tests performed on it.

Recording the chain of custody begins at the drill site. When the rock core is removed from a borehole, it is pulled out of the ground in one-foot increments about 2.4 inches in diameter. Blue and red orientation stripes are marked on the core to ensure the pieces aren’t mixed up or reversed.

At the Sample Management Facility, there are a number of processes used to record the origin of the samples kept there. The following is the usual sequence in the processing of core samples.


Receiving Area

Boxes of core arriving from the field are processed in the receiving area. In this area, workers enter information about the sample into a computer database. Some of this information includes what hole the sample came from and what processes it has undergone.

Some rock samples are put in cold storage where the temperature is about 45 degrees Fahrenheit, which minimizes the changes that could occur from biological and chemical activity. Other samples are sent to the specimen processing or sample preparation areas.

Specimen Processing Area

Within the specimen processing area, workers saw the rock samples into smaller portions called specimens. They then package and ship the specimens to various laboratories for further study.

Each specimen is labeled so that it can be readily identified.

Sample Preparation Area

In the sample preparation area, workers use special equipment to saw, grind, and polish thin slices of rock for microscopic study. Some samples are cut so thin that light shines through, making them transparent.

Initial field processing of core at the borehole.

The saws can cut up to about 96 feet of rock core an hour, wet or dry. A dust collection system protects the staff’s health. Other pieces of rock-processing equipment include a large slab saw and a drill press for removing smaller samples from larger pieces of core.

Core Examination Room

Authorized visitors, including Project geologists and hydrologists, examine a variety of samples in this room. The room is outfitted with binocular and petrographic microscopes to enable scientists to look for minerals in the rocks and other specific rock features.

Here scientists also study the core to determine what’s happened to the rock during its long history. This data provides clues to what the Yucca Mountain region might be like thousands of years from now.

Main storage area for core samples at the Sample Management Facility.

Sample Storage

The sample storage area can hold up to 100,000 linear feet of 2.4-inch rock core. This area also stores cuttings, bulk samples and specimen remnants returned to the facility by researchers. As always, the location of each sample is recorded in a tracking database.