Technical Area 21 (TA-21) is among the earliest of the Technical Areas to be constructed at Los Alamos National Laboratory. It was originally called the Delta Prime (DP) Site and may have pre-dated the use of “Technical Areas” to describe sites. It was divided into two sections, with DP West being a former radioactive material processing area, and DP East containing tritium facilities that provided space for energy, environment and weapons defense research.

TA-21 is also the site of the laboratory’s oldest waste disposal area, Material Disposal Area (MDA) B. This MDA and the other MDAs at TA-21 received waste for disposal intermittently from 1945-1977.

The demolition of 28 buildings and the remediation of three MDAs has been completed. The most recent demolition work occurred in 2015.

What remains at TA-21 is a large amount of above-ground debris left over from previous cleanup operations, a radioactive materials processing facility (Building 257—the last remaining permanent building), several above-ground tanks, two large mobile warehouses, obsolete equipment, and unused fencing and utility poles. Below-ground or at-grade material includes two large underground tanks (the General’s Tanks) containing radioactive effluent from material processing, underground waste transfer lines between buildings, building slabs and roadways, and buried waste.

In addition, two of the original five MDAs remain (MDAs A and T) and will be dispositioned as part of the overall TA-21 cleanup effort.

The TA-21 D&D and Cleanup Campaign includes the removal and remediation of buried waste lines and contaminated soils to be performed as part of the DP Site Aggregate Area investigation. Demolition of facilities and slabs is not part of the 2016 Consent Order and will be executed under DOE requirements. The facilities to be demolished include the DP West slabs and the Radiological Liquid Waste Treatment Facility, Building 257, enabling access to the Solid Waste Management Units and Areas of Concern.

Please read the Technical Area 21 fact sheet for more information on this campaign, including its current status.

You can also learn more about the Technical Area 21 D&D and Cleanup Campaign by downloading related presentations EM-LA has provided to the public on our Presentations page.