216-Z-12 transuranic crib characterization: operational history and distribution of plutonium and americium
Past radioactive liquid waste disposal practices at the Hanford Site included the discharge of process waste solutions containing low-level concentrations of plutonium directly to the ground via underground structures collectively termed cribs. The spatial distribution of plutonium and americium beneath the retired 216-Z-12 Crib has been studied. The 216-Z-12 Crib received low-salt aqueous waste from 1959 to 1973, when the crib was retired from service. The crib received 2.8 x 10/sup 8/ L of aqueous waste containing 25.1 kg of plutonium. Americium activity was determined to be derived from the in situ decay of /sup 241/Pu, not from a separate waste source. No other transuranic elements were discharged to the crib in any significant amounts. Wells were drilled in and around the crib using specialized techniques for obtaining radioactively contaminated sediment samples. Samples from each well are analyzed to determine sediment type, moisture content, and plutonium and americium concentrations. Study results show that plutonium concentration is highest (on the order of 1 to 5 million pCi/g of sediment) in the sediment immediately beneath the crib bottom. Plutonium concentrations decrease rapidly with distance from the bottom of the crib. Three meters below the crib, plutonium activity is less than 1000 pCi/g and 10 m below the crib, activity is less than 1 pCi/g. Plutonium activity increases to a few tens of picocuries per gram 30 to 36 m beneath the crib bottom. The activity is associated with a silt unit at that depth and is probably related to the silt unit's greater sorption capacity. Results from ground-water monitoring beneath the 216-Z-12 Crib indicate measurable concentrations of plutonium did not break through to the ground water.
- Research Organization:
- Rockwell International Corp., Richland, WA (USA). Rockwell Hanford Operations
- DOE Contract Number:
- AC06-77RL01030
- OSTI ID:
- 6858211
- Report Number(s):
- RHO-ST-44; ON: DE83005263
- Resource Relation:
- Other Information: Portions are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
Similar Records
216-Z-12 crib status report
Transuranic distribution beneath a retired underground disposal facility, Hanford Site
Related Subjects
AMERICIUM
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE STORAGE
AMERICIUM 241
RADIATION MONITORING
GROUND WATER
RADIOACTIVITY
PLUTONIUM
PLUTONIUM 238
PLUTONIUM 239
PLUTONIUM 240
SEDIMENTS
EXPERIMENTAL DATA
LIQUID WASTES
SAMPLING
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTINIDES
ALPHA DECAY RADIOISOTOPES
AMERICIUM ISOTOPES
DATA
ELEMENTS
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
HEAVY NUCLEI
HYDROGEN COMPOUNDS
INFORMATION
ISOTOPES
MANAGEMENT
METALS
MONITORING
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
OXYGEN COMPOUNDS
PLUTONIUM ISOTOPES
RADIOISOTOPES
STORAGE
TRANSPLUTONIUM ELEMENTS
TRANSURANIUM ELEMENTS
WASTE DISPOSAL
WASTE MANAGEMENT
WASTE STORAGE
WASTES
WATER
YEARS LIVING RADIOISOTOPES
510301* - Environment
Terrestrial- Radioactive Materials Monitoring & Transport- Soil- (-1987)
520301 - Environment
Aquatic- Radioactive Materials Monitoring & Transport- Water- (1987)