Soil water effects on concentration profiles and variations of /sup 222/Rn in a vadose zone

Journal Article · Sat Aug 01 04:00:00 EDT 1987 · Health Phys.; (United States)

OSTI ID:6376955

Fukui, M

Concentration profiles of /sup 222/Rn and their variations were studied to understand the vertical motion in the ground caused by fluctuations of meteorological parameters, such as precipitation, ground-water level and atmospheric pressure. A method of trapping /sup 222/Rn was developed to measure the concentration profiles by circulating and bubbling soil gas in porous cups into toluene. For locations where the water table is close to the surface, observations showed a peak concentration in the vertical profile of /sup 222/Rn at about a 40-cm depth and revealed that the concentration in soil gas decreases as soil moisture increases near the water table. Soil gas in a buried vessel also was circulated continuously to monitor /sup 222/Rn in the ground air near the surface using an ionization chamber. A rising of the water table following precipitation causes a burst of /sup 222/Rn concentration by upflow in the ground, though the concentration in the soil gas soon decreases with the intake of air above the surface due to increasing atmospheric pressure following precipitation. The concentration in soil gas again increases via the phenomenon accompanying the recovery of equilibrium in soil water between /sup 222/Rn and /sup 226/Ra.

• Research Organization: Kyoto Univ., Osaka, Japan
• OSTI ID: 6376955
• Journal Information: Health Phys.; (United States), Journal Name: Health Phys.; (United States) Vol. 53:2; ISSN HLTPA
• Country of Publication: United States
• Language: English

Related Subjects

510300* -- Environment
Terrestrial-- Radioactive Materials Monitoring & Transport-- (-1989)
520300 -- Environment
Aquatic-- Radioactive Materials Monitoring & Transport-- (1989)
54 ENVIRONMENTAL SCIENCES
ALPHA DECAY RADIOISOTOPES
ASIA
ATMOSPHERIC PRECIPITATIONS
ATMOSPHERIC PRESSURE
DAYS LIVING RADIOISOTOPES
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL TRANSPORT
EVEN-EVEN NUCLEI
GROUND WATER
HEAVY NUCLEI
HYDROGEN COMPOUNDS
ISOTOPES
JAPAN
MASS TRANSFER
MONITORING
NUCLEI
OXYGEN COMPOUNDS
RADIOECOLOGICAL CONCENTRATION
RADIOISOTOPES
RADIONUCLIDE MIGRATION
RADON 222
RADON ISOTOPES
RAIN
SOILS
WATER