Long-range alpha detection applied to soil surface monitoring

Conference · Wed Jan 01 00:00:00 EST 1992

OSTI ID:6719280

Caress, R W; Allander, K S; Bounds, J A; Catlett, M M; MacArthur, D W; Rutherford, D A

The long-range alpha detection (LRAD) technique depends on the detection of ion pairs generated by alpha particles losing energy in air rather than on detection of the alpha particles themselves. Typical alpha particles generated by uranium will travel less than 3 cm in air. In contrast, the ions have been successfully detected many inches or feet away from the contamination. Since LRAD detection systems are sensitive to all ions simultaneously, large LRAD soil surface monitors (SSMS) can be used to collect all of the ions from a large sample. The LRAD SSMs are designed around the fan-less LRAD detector. In this case a five-sided box with an open bottom is placed on the soil surface. Ions generated by alpha decays on the soil surface are collected on a charged copper plate within the box. These ions create a small current from the plate to ground which is monitored with a sensitive electrometer. The current measured is proportional to the number of ions in the box, which is, in turn, proportional to the amount of alpha contamination on the surface of the soil. This report includes the design and construction of a 1-m by 1-m SSM as well as the results of a study at Fernald, OH, as part of the Uranium in Soils Integrated Demonstration.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6719280
• Report Number(s): LA-UR-92-3428; CONF-930130-5; ON: DE93003722
• Resource Relation: Conference: 26. Health Physics Society midyear topical meeting on environmental health physics, Coeur d'Alene, ID (United States), 24-28 Jan 1993
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
SOILS
ALPHA DETECTION
RADIATION MONITORING
CONTAMINATION
RADIATION MONITORS
CHARGED PARTICLE DETECTION
DETECTION
MEASURING INSTRUMENTS
MONITORING
MONITORS
RADIATION DETECTION
540230* - Environment
Terrestrial- Radioactive Materials Monitoring & Transport- (1990-)
440101 - Radiation Instrumentation- General Detectors or Monitors & Radiometric Instruments