Spruce Twigs and Needles
Two samples, CLV-1 and CLV-2, consisting of spruce twigs and spruce needles, respectively, from the Cluff Lake uranium mining area in northern Saskatchewan, were prepared as analytical reference materials. Each sample was milled and ground to minus 212 :m, blended, and bottled in 125-g units.
The bottles were sealed in laminated aluminum foil-mylar pouches to maintain sample integrity. Opened bottles should be stored in a dessicator. All of the material was subjected to batch gamma-ray irradiation to a minimum dose of 25,000 Sv for sterilization purposes.
Nine laboratories participated in the interlaboratory program to provide analytical results for uranium and five radionuclides.
A copy of CANMET Report NUTP-4E, "Vegetative Radionuclide Reference Materials", will be provided with each order of CLV-1 or CLV-2.
|Pb-210||0.66 Bq/g||0.074 Bq/g|
|Po-210||0.49* Bq/g||0.073 Bq/g|
|Ra-226||0.70 Bq/g||0.038 Bq/g|
|Th-230||0.31 Bq/g||0.033 Bq/g|
|Cs-137**||0.11 Bq/g||0.034 Bq/g|
|Uranium||86.8 μg/g||3.6 μg/g|
*As of January 1986; expected to reach the confidence limits of Pb-210 by October 1986, and thereafter remain in radiochemical equilibrium with Pb-210.
** Provisional value.
** wt %