Re Radon Emanation / Tilling Soil

["Leo M. Lowe" <llowe@senes.on.ca>]

The radon that is available for release during soil tilling is that radon
that is within the pore spaces of the soil. This is variable and dependent
on soil type and characteristics but is "typically" about 20% of the radon
that is produced from the parent Ra-226.

Assuming for present purposes a unit soil concentration of 1 Bq Ra-226/g, a
tilling depth of 20 cm, a soil density of 1.6 g/cm3, and that all the pore
radon is released (a not too unreasonable assumption), the radon that is
released per cm2 of tilled soil is then

    1 Bq/g x (1 cm2 x 20 cm) x 1.6 g/cm3 x 0.2 = 6.4 Bq per cm2 plowed.

This can be converted to a release rate (Bq/s) by multiplying by the area
plowed and dividing by the plowing time.

Regards,

Leo M. Lowe, Ph.D.
Principal, Senior Health and
Environmental Physicist

SENES Consultants Limited
121 Granton Drive, Unit 12
Richmond Hill, Ontario
Canada L4B 3N4
Tel:	(905) 764-9380
Fax:	(905) 764-9386
email:	llowe@senes.on.ca
WWW:	www.senes.on.ca (under renovation)
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