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TA-54 More Details |
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March 1998 1 9 0 TA and Facilities Descriptions ©2004 lasg.org |
TA-54 More Details
March 1998 1 9 0 TA and Facilities Descriptions
4.31.2.1 Facility Hazard Categories
Table 4-27 identifies the facilities at TA-54 that fall into a facility hazard category because of the
type of operations performed in the facility. The following discussion of facility hazard categories
focuses on the various areas rather than on individual buildings. Unless noted otherwise, all the
buildings involved in handling waste in a given area bear the same hazard category as that of the
area.
4.31.2.1.1 Nuclear Facility Hazard Categories
All of Area G is categorized as a Hazard Category 2 nuclear facility. However, on the accompanying facility maps, only significant buildings in this category are shaded. In addition, Building 38, the Radioassay and Nondestructive Testing Facility, in Area G West is categorized as a Hazard Category 2 nuclear facility.
4.31.2.1.1.1 Area G
Area G (Figure 4-31, Sheet 3) is a 63-acre (25.5-ha) site located at the east end of TA-54. The
area provides intermediate and long-term storage sites for wastes generated at the Laboratory.
Major Area G waste management units include numerous LLW disposal pits and waste storage
and disposal shafts, most of which have been closed; TRU waste pads and storage domes, which may include low-level mixed waste, if needed; a facility for decontaminating radioactive waste containers and contaminated equipment; two compactor facilities for LLW; and an administrative support building that contains a locker room and a decontamination shower. The area has been in use since 1957 and is expected to remain active for the foreseeable future.
In 1977, the active portion of Area G was expanded to its current 63 acres (25.5 ha). Before 1985, low-level mixed waste was disposed in pits at this site. The surface structures are predominantly membrane-covered domes supported by arch frames, which are used for waste storage. Subsurface structures include waste disposal pits excavated in volcanic rock and auger-bored shafts for storing and disposing of radioactive wastes in various forms. Entry is permitted through a monitored gate at the west end of Area G.
Processes at Area G include waste receipt, handling, storage, compaction, and disposal. These
low-complexity operations involve trucks, forklifts, and heavy equipment to safely convey, manipulate, handle, and/or dispose of containers of waste. Other routine operations include decontaminating vehicles, equipment, and metal waste containers, as necessary; sanding and painting drums; overpacking damaged or potentially degraded waste containers; auditing and inspecting waste disposal and storage operations; constructing or closing pits and shafts; and conducting general facility maintenance activities.
• Disposal Pits and Shafts. At present, subsurface disposal units include 35 pits, approximately
260 shafts, and 4 trenches. Guidelines for constructing disposal units at Los Alamos
were developed in conjunction with the US Geological Survey. Pits typically cover 24,608
ft2 (7,500 m2) and are approximately 65.6 ft (20 m) deep. Shafts range from 0.98–8.3 ft
(0.3–2.5 m) in diameter and are up to 65.6 ft (20 m) in depth. Pits are excavated in at least
50 ft (15 m) from the edge of the mesa, and their bottoms are at least 9.84 ft (3 m) above the
floor of adjacent canyons.
• Buried Wastes. Area G consists of 80 acres (32 ha), of which 37 acres (15 ha) has been developed and is the currently active radioactive waste management area. This 37-acre (15-
ha) area holds legacy waste, including TRU waste disposed before 1971 and mixed LLW
disposed before the passage of the Resource Conservation and Recovery Act in 1976, as
well as LLW buried since 1958. Five pits (15, 31, 37, 38, 39) in the 37-acre (15-ha) area are
active, all of which are used for disposal of LLW. As of January 30, 1997, the 5 pits had a remaining disposal capacity of about 85,306 ft3 (26,000 m3). Enough space remains in this
area to provide pit capacity for about another 32,810 ft3 (10,000 m3) of wastes. After this capacity has been used, continued disposal of LLW at TA-54 would require expansion of disposal operations beyond the current 37 acres (15 ha).
• Temporary Retrieval Dome (Building 226, Figure 4-31, Sheet 3). This large [approximately
21,000 ft2 (6,400 m2)], fabric-covered structure is the site of the TRU Waste Inspectable
Storage Project (TWISP), which involves inspecting the approximately 17,000 drums of
TRU waste that have been stored and covered with earth at TA-54 awaiting shipping to the
DOE’s Waste Isolation Pilot Plant (WIPP). The dome provides an enclosure and weather
protection for workers during the time required to retrieve the containers and inspect them.
• Drum Preparation Facility (Building 33, Figure 4-31, Sheet 3). This building houses activities
that are part of the Drum Recovery Project. The facility provides (1) bays for steam
cleaning and painting drums of TRU waste retrieved during the TWISP, (2) water sedimentation
pits and collection tanks, (3) a drum-venting system that will safely puncture and vent
retrieved drums of TRU waste, and (4) a general-treatment bay that will be used for reducing
the volume of gloveboxes and similar large waste items and for segregating the different
waste types.
• Compactor Facility (Building 281, Figure 4-31, Sheet 3). This building houses a waste compactor that has 200 tons (181,440 kg) of compressive force, which can reduce volume as
much as eight times. Compacting waste helps to conserve disposal space and minimizes soil subsidence at the disposal pit. A smaller compactor is used to crush items such as empty drums.
• Tension Support Buildings (Buildings 49 and 224, Figure 4-31, Sheet 3). These domes are
used for storing mixed LLW. An asphalt pad adjacent to Building 49 is used for outdoor
storage of pyrophoric uranium waste chips.
• Sheds (Buildings 144, 145, 146, and 177). The sheds (which are too small to show up on
the maps) are used for storing mixed tritiated wastes.
• Tension Support Buildings: Buildings 48, 153, and 283 (Figure 4-31, Sheet 3). These
domes are used for newly generated TRU waste.
• Tension Support Buildings (Buildings 229, 230, 231, and 232, Figure 4-31, Sheet 3).
These domes [16,000 ft2 (4,877 m2) each] are used for legacy TRU waste retrieved during
the TWISP.
• Storage Pads 2, 3, and 4 (Figure 4-31, Sheet 3). These asphalt pads hold legacy TRU
waste in drums and other containers. During the 1970s and 1980s, the pads and containers
were covered with earth. Wastes are currently (1997) being retrieved and placed in
abovesurface storage domes to permit inspections required by the Resource Conservation
and Recovery Act and to ensure that wastes and containers are in a form suitable for disposal.
4.31.2.1.1.2 Area G West
Area G West (also called TA-54 West) is the site of the Radioassay and Nondestructive Testing
(RANT) Facility (Building 38, Figure 4-31, Sheet 1). The functions of the RANT Facility (formerly
known as the Nondestructive Assay/Nondestructive Examination Facility) are to determine the
characteristics of packaged waste, which involves detecting liquids, void spaces, and fissionable materials. RANT will also serve as the loading station for shipments of TRU waste when WIPP begins disposal operations.
All radioactive and mixed waste received at this site must meet waste acceptance criteria to ensure safety, environmental protection, and regulatory compliance. TRU waste must also be shown to meet the waste acceptance criteria applicable to WIPP. In lieu of opening and examining waste containers, nondestructive techniques are used to verify the contents of waste to prevent worker exposure and escape of contaminants to the environment.
Verification assay and radiographic examination of unopened containers of radioactive and mixed waste take place at RANT. The facility will also serve as a certification and staging facility for TRU waste to be transported to WIPP.
The major assay and examination equipment includes a 320-keV real-time radiography system, a passive/active neutron interrogation assay system, an airport-type x-ray system, a platform scale, and a gas proportional smear counter. Other equipment in the facility includes powerlift trucks, a dock leveler, and various types of rigging and materials-handling equipment. The airport x-ray, radiography, and neutron systems are each contained in separate shielded cabinets.
The RANT Facility, which is divided into two high-bay areas, is approximately 6,400 ft2 (1,951 m2).
One of the bays has a mezzanine that houses offices and rest rooms. The waste drums are received at the loading dock attached to this bay. The other bay area, originally built for loading TRU waste into TRUPACT-II containers, can be used to store and assay waste in the future and will be used as a staging area for mobile assay equipment. The exterior load-bearing walls are precast concrete panels. The floor is a reinforced-concrete slab on compacted fill. The roof of the facility is a single-ply membrane roof with ballast over prestressed-concrete double T-beams. Utilities include electrical power and water for domestic, industrial, and fire-fighting purposes. Emergency support services are accessible by radio and telephone.
All radioactive and mixed wastes are contained. TRU solid wastes and mixed wastes are contained in metal drums. Compactable LLW may be packaged in cardboard boxes.
Containers with excessive removable surface contamination and leaking containers are not permitted inside this facility.
4.31.2.1.2 Non-Nuclear Facility Hazard Categories
4.31.2.1.2.1 Building Categorized M/CHEM
Building 1008 (Figure 4-31, Sheet 1), a drinking water chlorination station, is categorized as
M/CHEM.
4.31.2.1.2.2 Areas Categorized L/CHEM
Area L (Figure 4-31, Sheet 2), an area of 2.65 acres (1.07 ha), provides storage and shipment of wastes managed under permits required by the Toxic Substances Control Act and the Resource Conservation and Recovery Act. It also stores liquid waste and waste containing volatile organic compounds, both of which are also contaminated with hazardous and/or radioactive components.
A portion of Area L is used for storing nonradioactive, PCB-contaminated waste oils and empty
transformers. In addition to permitted storage, Area L houses treatment tanks for barium-contaminated sand and ammonium bifluoride. The waste stored and/or treated at Area L is ultimately shipped to other locations, both on- and offsite, for disposal, treatment, or recycling.
Chemical wastes were disposed at Area L from the 1950s until December 1986. Inactive disposal units include 1 pit, 3 surface impoundments, and 34 shafts, with a total disposal capacity of 6,575 ft3 (2,004 m3). Noncontainerized solids and liquids drummed without absorbent were disposed in unlined pit and shafts. Unlined surface impoundments were used to evaporate treated salt solutions such as ammonium biofluoride and electroplating waste solutions. An unlined impoundment was also used to react lithium hydride with water and to serve as secondary containment for waste oil tanks. These former operations are being investigated as part of Operable Unit 1148 in the Environmental Restoration Program at the Laboratory.
Important structures at Area L are discussed below.
4.31.2.1.2.2.1 Liquid-Low-Level-Mixed-Waste-Storage Building
The Liquid-Low-Level Mixed Waste Storage Building (Building 215) is a large [16,000-ft2 (4,877- m2)] new structure used for storing drums of liquid low-level mixed wastes. The building has a bermed asphalt floor, an unfiltered exhaust stack, interior lighting, and an overhead fire suppression system.
4.31.2.1.2.2.2 Gas Cylinder Canopy
The Gas Cylinder Canopy (Building 216) is a roofed facility of 4,000 ft2 (1,220 m2) with a single wall used to store gas cylinders until they can be shipped offsite for treatment and disposal.
4.31.2.1.2.2.3 PCB Building
Liquid and solid PCB wastes are stored at the PCB Building (Building 39) until they are shipped
for treatment and disposal. Some of the liquid wastes are also contaminated with hazardous and/ or radioactive wastes.
4.31.2.1.2.2.4 Liquid Chemical Storage Canopy
The Liquid Chemical Storage Canopy (Building 32) is an open structure in which drums of liquid
chemical wastes are stored. The drums are segregated for chemical compatibility and stored in
the appropriate section.
4.31.2.1.2.2.5 Lab Pack Storage Units
Small quantities of hazardous wastes are placed in 5-gal. (19-L) lab packs, which are placed in
small storage units (Buildings 68, 69, and 70). Lab packs are segregated for chemical compatibility and stored in these small sheds until they are shipped for treatment and disposal. The storage units are equipped with secondary containment.
4.31.2.1.2.2.6 Sampling, Shipment, and Treatment Canopies
The sampling, shipment, and treatment canopies (Buildings 35, 36, and 58) are sheltered pads
that have overhead covering but no sides. Building 35 contains two treatment tanks that are not
currently in use. Canopy 36 holds equipment used to survey and sort mixed wastes.
4.31.2.1.3 Building Categorized L/RAD
Samples of mixed waste from environmental restoration and waste management operations are
analyzed for organic hazardous constituents at the Mixed-Waste Analysis Laboratory (Building
1009, Figure 4-31, Sheet 1). The samples consist of extractions of small amounts of water, soil,
and sludge.
4.31.2.2 Nonhazardous Facilities
4.31.2.2.1 Area H
Radioactive wastes were disposed in nine shafts at Area H [Figure 4-31 (index map of TA-54)]
until 1986, when disposal was discontinued. The Environmental Restoration Program is now
investigating this small, 0.3-acre (0.12-ha) site as a solid waste management unit under the Resource Conservation and Recovery Act. There are no aboveground structures at Area H.
4.31.2.2.2 Area J
Area J (Figure 4-31, index map of TA-54) is 2.65 acres (1.07 ha) and has been used since 1961
for disposal of industrial solid wastes. The area has six disposal pits and four disposal shafts. Pits 1 and 2 are filled and capped with soil. Pit 3 is filled and capped with asphalt, and an asbestos transfer station is located on the asphalt. Pit 4, the largest, is 70% filled. Pits 5 and 6 are less than 10% filled. Two of the four shafts are filled and capped with concrete. Shafts 3 and 4 are less than 10% filled. The shafts are 6 ft (1.8 m) in diameter and 60 ft (18.3 m) deep. The size of the pits varies.
Five kinds of waste management operations are conducted at Area J:
• Administratively controlled industrial solid wastes are disposed. Three pits are open, three
had been filled as of January 1997. The State of New Mexico permits disposal at Area J
under an interim permit.
• Previously hazardous wastes are disposed at Area J. In the past, barium-contaminated soils
were neutralized at TA-54, Area L, then disposed at Area J in the same pits used for industrial
wastes. The last such disposal occurred in 1993.
• Classified industrial wastes are disposed in shafts. There are four shafts, each 60 ft (18.3 m)
deep and 5 ft (1.5 m) in diameter. Two of the shafts are filled, and two are nearly empty.
• An asbestos transfer station is operated pursuant to New Mexico Environment Department
(NMED) regulations. Two roll-off containers are used to store friable asbestos wastes, and
nonfriable asbestos wastes are stored on an asphalt pad. All asbestos wastes are shipped
offsite to permitted asbestos disposal facilities.
• Oil-contaminated soils are land-farmed under interim permit from NMED. Soil is turned periodically, and soils are sampled for hydrocarbon content. The land farm covers an area of
8,200 ft2 (2,500 m2). Oil-contaminated soils have not been added to the land farm area
since 1992.
4.31.2.2.3 Other TA-54 Facilities
A number of buildings at TA-54, which consist mainly of offices, general storage, passageways,
and pump stations, are not considered to be hazardous. These buildings are located outside of
the various hazardous areas.©2004 lasg.org