SOIL-MOISTURE PREDICTION METHOD FOR NRDL INDUCED-ACTIVITY PREDICTION SYSTEM

Technical Report · Wed Jul 17 04:00:00 EDT 1963

OSTI ID:4056624

Laumets, E

Pant of the military problem of predicting the gammaradiation doses at 3 feet above the ground produced by the radioactivity induced in soil elements by neutrons emitted from nuclear air bursts is that of predicting the moisture content in the top soil layer of interest. The greater the moisture content in this layer, the closer to the surface lies the major part of the thermal neutron flux, since hydrogen atoms in the water are highly effective in thermalizing neutrons. Thus, there is less attenuation of the resulting gamma radiation by the soil. A method of predicting the soil moisture content in the top 6 inches of soil is described. The method, whose computational procedure follows a simplified bookkeeping'' form, is based on sofl textures and experimental values on daily moisture accretion and depletion for different seasons of the year. The method is applicable to both free and impeded drainage conditions. The method is demonstrated by simple and complex examples. (auth)

• Research Organization: Naval Radiological Defense Lab., San Francisco
• NSA Number: NSA-18-016206
• OSTI ID: 4056624
• Report Number(s): USNRDL-TR-662; AD-416807
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BARRIERS
GAMMA RADIATION
GEOLOGY AND MINERALOGY
HUMIDITY
HYDROGEN
NEUTRON FLUX
NEUTRONS
NUCLEAR EXPLOSIONS
SEASONS
SOILS
THERMAL NEUTRONS
WATER