The Site is a former radioactive material processing laboratory. The produced and prepared sealed sources and tracers for the medical, oil production and exploration, and chemical industries. Since, the company had been in Chapter 11 bancruptcy but on the 16th of October, 2001, the presiding judge moved it into Chapter 7, virtually causing the site to be abandoned.
Radioactive sources, highly contaminated equipment and debris, and contaminated buildings remain at the Site. Radioactive Americium, Cesium, and Radium are the primary isotopes found but the radioactive isotopes of Silver, Thorium, Plutonium, Europium, Cobalt, Iridium, Strontium, and several others are found in significant quantities at the Site. The Site is located in a densely populated area near medical clinics, hospitals and other commercial operations.
Crews investigated and segregated material in the buildings. The crews had to work around rooms with the ambient radiation that limited time allowable in the rooms. In some rooms, the annual allowable dose for a radiation worker would have been exceeded in less than 13 minutes. The gamma activity inside some of the components exceeded 1000 R/Hr. Alpha scans of the floors has shown 200,000,000 disintergrations (or counts) per minute. State investigations have found radioactive rats and roaches (2 mR/h and 20,000 - 30,000 pCi). Several neutron fields exist through out the Site. Some of the neutron fields were due to instruments set up in the labs, but others existed due to loose piles of Americium and Beryllium found in several areas in the building.
Crews had to choreograph some of the work prior to making the entries in order to limit their exposure. Additional shielding had to be constructed to enter some rooms and moved in ahead as the crews advanced into the rooms.
Initially, the report had indicated that only a dozen sealed sources were in the building. However, the cleanup found about 300 sealed sources. That included several small check sources, packets of 100's of radium needles (a packet was counted as a single source), and several 125 Curie Cesium-137 sealed sources. These were found in cabinets, rolling on the floor, in coffee cups, in the glove-boxes, behind false walls, and hidden in the base of a large component.
Several items required special handling and a variety of waivers. One large component would have required about 1200 man-Rem, or the annual exposure of about 240 radiation technicians, to dismantle it to comply with standard disposal specifications. The State of South Carolina approved a waiver to allow that and other components to be received as a whole unit. That included the 81,000 pounds of lead shielding in a component that if removed would not have allowed for the transportation of the component due to the radiation level going down the road. That lead to the special permits and waivers to transport items that heavy on the road to the disposal facility. Cask and specially designed containers were used to ship the waste streams to the disposal facilities.
Many of the items and some subsequent derived waste is classified as “Greater Than Class C” (GTCC). Separate waste streams exceeded the alpha contamination from the Americium-241 and gamma contamination from the Cesium-137. There is currently no commercial disposal facility for GTTC waste. The State of Texas has worked with EPA and a facility to allow the storage of the GTCC waste until a facility becomes available. It is expected that the GTCC will go to the Yucca Mountain facility when it opens. It is projected that the Yucca Mountain facility will begin accepting waste no earlier than 2010.
The buildings and foundations have been removed and disposed of offsite. Crews began in November 2003 removing the contaminated soil and driveways. It is expected that the soil contaminated greater than 35,000 pico-Curies of Cesium-137 and 500 pico-Curies of Americium-241 will be excavated to meet the cleanup criteria of 40 pico-Curies of Cesium-137 and 6 pico-Curies of Americium-241. Reaching that cleanup goal will allow the State of Texas to “free release” the property for unrestricted reuse.
