Method and apparatus for detecting alpha particles in a sample containing sample media and water

1 . A method of detecting alpha particles in a sample comprising a sample media and water using a portable detection apparatus, the method comprising:

a) providing a layer of a scintillating slurry comprising a granular scintillating material in water onto a measurement surface of the sample;

b) positioning the sample having the scintillating slurry within a detection chamber of detection apparatus;

c) detecting photons produced by the granular scintillating material in the scintillating slurry when the granular scintillating material is excited by ionizing alpha radiation emitted by alpha particles within the sample using a photon detector and generating a corresponding output signal;

d) removing the sample and the scintillating slurry from the detection chamber.

2 . The method of claim 1 , further comprising disposing of the sample and the scintillating slurry after step d).

3 . The method of claim 1 , wherein the scintillating slurry covers substantially the entire measurement surface of the sample.

4 . The method of claim 1 , wherein the measurement surface is non-uniform.

5 . The method of claim 1 , wherein the alpha particles in the sample are present in the sample media in the sample and wherein the water in the sample is substantially free of alpha particles.

6 . The method of claim 1 , wherein the scintillating slurry is formed prior to step a) by mixing the granular scintillating material with water and the pre-mixed scintillating slurry is applied to the measurement surface in step a).

7 . The method of claim 1 , wherein the scintillating slurry is formed during step a) by depositing a dry powder comprising the granular scintillating material onto the measurement surface, wherein dry powder comprising the granular scintillating material mixes with at least one of the water present in the sample and a quantity of water applied to the measurement surface thereby forming the scintillating slurry in situ on the measurement surface.

8 . The method of claim 7 , further comprises depositing the dry powder comprising the granular scintillating material onto the measurement surface and then applying a mist of water onto the measurement surface thereby forming the scintillating slurry in situ on the measurement surface.

9 . The method of claim 7 , further comprises applying a mist of water onto the measurement surface and then depositing the dry powder comprising the granular scintillating material onto the measurement surface, thereby forming the scintillating slurry in situ on the measurement surface.

10 . The method of claim 1 , further comprising transporting the detection apparatus to a testing location and obtaining the sample from the ground at the testing location prior to performing step a).

11 . The method of claim 1 , further comprising depositing the sample in a sample holder prior to step a), wherein the sample holder is insertable into the detection chamber in step b) and removable from the detection chamber in step d).

12 . The method of claim 11 , wherein the detection chamber configurable in an open configuration in which the sample and layer of scintillating slurry is insertable or removable from the detection chamber and a closed configuration in which external ambient light is excluded from the detection chamber.

13 . The method of claim 1 , further comprising comparing the output signal to a predetermined output threshold value and, if the output signal exceeds the output threshold value, displaying a user output on a user display device.

14 . The method of claim 13 , further comprising amplifying the output signal prior to comparing the output signal to the predetermined output threshold value.

15 . The method of claim 1 , further comprising detecting alpha particles in a second sample comprising the sample media and water using the portable detection apparatus, the method comprising:

e) after completing step d), providing a second layer of the scintillating slurry comprising the granular scintillating material in water onto a measurement surface of the second sample;

f) positioning the second sample having the second layer of the scintillating slurry within the detection chamber of detection apparatus;

g) detecting photons produced by the granular scintillating material in the second layer of the scintillating slurry when the granular scintillating material is excited by ionizing alpha radiation emitted by alpha particles within the second sample using a photon detector and generating a corresponding second output signal;

h) removing the second sample and the second layer of the scintillating slurry from the detection chamber.