TA-53 More Details

March 1998 1 8 0 TA and Facilities Descriptions Facility Hazard Categories
Table 4-26 identifies the facilities at TA-53 that fall into a facility hazard category because of the
type of operations performed in the facility.
March 1998 1 8 1 TA and Facilities Descriptions Nuclear Facility Hazard Categories
TA-53 contains one Hazard Category 3 nuclear facility located in Building 3M in Experimental Area
A, which currently houses the Isotope Production Facility. The facility is not nuclear at the time the
nonirradiated targets, whose radioactive inventory is zero, are initially inserted in the beam line. It
is not until irradiation begins and activation products in the isotope production targets reach Category
3 levels that the area is considered to be nuclear.
Isotope production refers to the ongoing process in which valuable radioisotopes, including
those for medical use, are produced by the linear accelerator. Materials irradiation is a similar process
conducted to ascertain the effects of beam irradiation on material properties. Because inventories
of radioactive materials in the isotope production facility develop as a result of irradiation
and cannot be measured beforehand, an inventory limit is calculated to ensure that the hazard
category does not rise to levels beyond that projected. Non-Nuclear Facility Hazard Categories
Twenty-two L/RAD facilities and 5 L/ENS facilities are located at TA-53. Only the more significant
facilities are discussed below; the rest of the facilities are identified in Table 4-26 and on the
accompanying figures. Buildings Categorized L/RAD Laboratory and Office Building
The Laboratory and Office Building (Building 1, Figure 4-30, Sheet 2) houses both offices and
laboratories. The laboratories have been used for radiochemistry activities and therefore are categorized
as L/RAD. The offices are normally separated from the laboratories. Linear Accelerator
The Linear Accelerator (Building 3, Sectors A, B, C, D, E, F, G, H, J, N, P, R, and S) (Figure 4-30,
Sheets 2 and 3) is more than a half-mile in length and has 316,000 ft2 (96,317 m2) of floor space,
which is about one-third of the total area under roof at TA-53. The building contains equipment to
form H+ and H- proton ion beams and to accelerate the beams to 84% of the speed of light. Ancillary
equipment is used to transport the proton ion beam; maintain vacuum conditions in the beam
transport system; and provide heating, ventilation, and cooling. The beam tunnel itself is located
35 ft (10.7 m) below grade to provide radiation protection. Abovesurface structures house the
radiofrequency power sources used to accelerate the beam.
Experimental Area A is the largest [~32,000 ft2 (~9,754 m2)] of the experimental areas at TA-53.
This area has housed numerous meson experiment stations in the past. By 1998, all experimental
stations will be dismantled and removed, to be replaced by a major new experimental facility,
the Long-Pulse Spallation Source (LPSS). LPSS will include the use of ultracold neutrons as a
research tool, an area of research that is just beginning to emerge. LPSS will be designed to have
14 beam lines for neutron-scattering research and another for high-energy neutron research.
Sector N (Experimental Area B) currently houses several experimental stations that are no longer
funded. Facilities for the production of exotic medical isotopes may be located here within the
next five years. Sector P (Experimental Area C) currently holds the High-Resolution Spectrometer,
which will be dismantled and removed by 1998. A Proton Radiography Firing Site will be constructed
in its stead as part of the Laboratory’s Science-Based Stockpile Stewardship Program.


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