TA-18 More Details

March 1998 8 0 TA and Facilities Descriptions Facility Hazard Categories
Table 4-10 identifies the facilities at TA-18 that fall into a facility hazard category because of the
type of operations performed in the facility. Nuclear Facility Hazard Categories
Four buildings in TA-18 are categorized as Hazard Category 2 nuclear facilities (Figure 4-12,
Sheet 1). These buildings are the Kiva 1 (Building 23), Kiva 2 (Building 32), and Kiva 3 (Building
116)—all of which are critical assembly buildings—and the Hillside Vault (Building 26). Each kiva is
surrounded by a security fence, and entrance to the kivas is controlled by several layers of security
and safeguards. Each kiva contains its own storage vault equipped with metal lockers for storing
SNM containers. Permissible load limits are posted at the vaults. Because the vaults have no
outside entrances, personnel must enter through the kiva building.
March 1998 8 1 TA and Facilities Descriptions
The kivas are constructed of reinforced concrete and masonry block and are designed to minimize
fire risks. Each kiva is equipped with a traveling crane in the main assembly area. Gas-fired furnaces
are used for heating, and the building is equipped with forced-draft ventilation. Each kiva
has rooms for storing SNM, which are locked and show posted load limits. Fire-fighting equipment,
consisting of an automatic sprinkler system and a fire alarm system, is provided in the control
Electrical power, water, and sewer are the only systems shared by the kivas. Loss of power to
LACEF deenergizes all control circuits, aborting the operation and thereby preventing startup or
shutdown of the reactor or experiment. Sharing common systems cannot result in a critical assembly
incident. Because critical assemblies do not need to be cooled, no emergency power is needed
to prevent exceeding fuel temperatures at which damage occurs.
Each kiva is surrounded by a physical security boundary. The area inside the security boundaries
is evacuated before remote operation begins, and automatic signal alarms forewarn anyone who
is overlooked. Kiva 1
Kiva 1 (Building 23, Figure 4-12, Sheet 1) is approximately 1,440 ft2 (439 m2). Its primary safety
feature is its remoteness from the nearest occupied facility. A control gate prevents access to the
area when critical experiments are under way. The gate and the alarms are tied to a serial interlock
safety system. Kiva 1 houses four general-purpose machines for remotely assembling critical experiments.
These machines contain no permanently mounted nuclear fuel. Critical experiments
involving enriched uranium solutions are routinely conducted in Kiva 1. The control system in
Control Room 1 (located in Building 30) consists of a standardized interlock and protection system
with a digital machine control system. Energizing the machine activates the control system.
Power to the assembly is supplied when all inputs to the Kiva 1 serial interlock have been verified.
One additional critical assembly building, the Sheba Building (Building 168), is located inside the
Kiva 1 security perimeter. Although the Sheba Building provides a weatherproof shelter for critical
experiment assemblies, no radiation shielding is afforded by the structure. This allows radiation
dose measurements to be taken and radiation instruments to be placed around the critical assemblies
in the enclosure without the interference of shielding or building scatter. Kiva 2
The floor space at Kiva 2 (Building 32, Figure 4-12, Sheet 1) is approximately 1,740 ft2 (530 m2).
The construction and primary safety features at Kiva 2 are similar to those of Kiva 1. Kiva 2 houses
two benchmark assemblies and one general-purpose assembly machine.
The three assemblies manipulated from Control Room 2 (located in Building 30) have similar but
independent control systems. The control systems use conventional analog control technology
with direct-wired electrical switches and panel indicators. Selection of a machine energizes the
appropriate control system. Power to the assembly is supplied after verification of the Kiva 2 serial
interlock. Kiva 3
The floor space at Kiva 3 (Building 116, Figure 4-12, Sheet 1) is approximately 5,184 ft2 (1,580
m2). The construction of Kiva 3 is similar to that of Kivas 1 and 2, except that Kiva 3 has significant
shielding because it is closer to the nearest occupied building than the other two kivas.
March 1998 8 2 TA and Facilities Descriptions
For producing fast-neutron pulses, Kiva 3 has two fast-burst assemblies operated from Control
Room 3 (located in Building 30). The assemblies have control systems similar to those in Control
Room 2. The control system is energized, and power is supplied to the assembly only after the
proper settings of the Kiva 3 serial interlock have been verified. Hillside Vault
The Hillside Vault at TA-18 (Building 26, Figure 4-12, Sheet 1) consists of two rooms whose overall
floor space is 216 ft2 (66 m2). The vault, which is used to store SNM and fissile components of
various assembly devices, is unheated and is usually unoccupied. The walls, floor, and ceiling are
constructed of reinforced concrete, and the interior is lined with heavy steel shelves solidly anchored
to the walls. The shelves are subdivided into storage locations, each of which holds a
defined limit of SNM in sealed storage containers. Each container is stored in a designated location.
The containers are transported to other locations at TA-18 for use in experiments and radiation
measurements. The vault is equipped with heat and smoke detectors, which are connected
to a central alarm station offsite. When locked, the vaults are monitored by alarm systems. The
vaults are under the control of the Laboratory's protective force.
The Hillside Vault also stores fissile components of the various assembly devices. A wide range of
assembly components is maintained at the site to ensure flexibility in conducting experiments. All
fuels at LACEF have radiation levels that allow monitored handling. Only authorized personnel
have routine access to this vault. Non-Nuclear Facility Hazard Categories
Five facilities are categorized L/RAD (Figure 4-12, Sheet 1). Pulsed Accelerator Building
The Pulsed Accelerator Building (Building 127), also known as the High Bay, is located next to the
canyon wall at the north side of the site. It consists of a large room under which is a basement that
contains an office complex. The experimental bay features a false floor and low-density walls to
minimize radiation scatter. This feature has led to the use of the facility for measurements that require
a “clean” radiation environment. A two-story-high shield wall separates the experimental bay
from the rest of the site. Reactor Subassembly Building
The Reactor Subassembly Building (Building 129) is located at the northeast end of the site. It
consists of one large room and several compartmentalized office/laboratory spaces. Both neutron
and gamma-ray sources are used for detector development and calibration procedures. “Reactor
Subassembly Building” is the building’s historical name; nuclear reactors are not assembled in this
building. Accelerator Development Laboratory
The Accelerator Development Laboratory (Building 227) is located next to the canyon wall at the
north side of the site. The building consists of one story and a basement. The walls and roof are
constructed of prestressed concrete with a steel floor between the first floor and basement. The
principal experimental area and control room are located in the basement, which is naturally shielded
by the surrounding earth. The Accelerator Development Laboratory is a multipurpose experimental
laboratory that accommodates such activities as radiography with isotopic sources, development
of portable linear accelerators, and associated particle imaging. Other capabilities include
March 1998 8 3 TA and Facilities Descriptions
further accelerator design and development, resonance adsorption imaging, and liner array imaging. Transportainers
The transportainers (Buildings 247 and 249) are used for storing encapsulated radioactive
sources. Nonhazardous Facilities
Thirty-two other structures, consisting primarily of administrative, technical, laboratory, general
storage, trailers, and guard towers and stations are listed as nonhazardous. The Central Office
Building (Building 30) houses the main offices of several groups, as well as several counting laboratories,
electronic assembly areas, the TA-18 machine shop, and the control rooms for the three



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