9
Program F –
Procedure for the Analysis of Water in Soils and Solids
(Reagent Systems: HS-SEV)
1.
PREPARATION:
Remove a sampling syringe and a white-capped reaction tube from the reagent box and the
extraction solvent ampule from the colored-capped soil extraction tube. Check the contents to ensure that all
items are present and intact. Remove the white cap from the reaction tube and discard. Carefully remove a
green water ampule from the cardboard carton and insert it fully into the top of the protective ampule sleeve
containing the grayish white ampule. Return the protective ampule sleeve to the reaction tube with the grayish
white ampule on the bottom; place the reaction tube into the reagent box.
2.
SAMPLE EXTRACTION:
Remove the colored cap from the soil extraction tube and tare on an electronic
scale. Weigh 5-10 grams of soil to be tested into the soil extraction tube and record the weight. Add the
contents of one break-top ampule of extraction solvent (white polypropylene top) to the soil extraction tube, re-
cap and shake for 1 minute. Allow soil in the soil extraction tube to settle for 2 minutes.
3.
SAMPLING EXTRACTED SAMPLE:
Work the plunger of the empty sampling syringe a few times to ensure
that it slides easily. After soil has settled, draw up a sample from the extract layer with the sampling syringe
ensuring that there are no air bubbles in the syringe. If air bubbles are present, depress the plunger again and
draw a second sample slowly. Wipe any excess solvent from the outside of the syringe with a tissue wipe and
dispense the sample into the reaction tube, be sure not to blot the tip of the syringe. Insert the black septum
(hole on top) into the reaction tube by gripping the tube firmly and pressing down on the septum with your
thumb until flush with top of the tube.
TIGHTLY
cap the tube with the holed, white cap
. NOTE: DO NOT
SQUEEZE THE SIDES OF THE TUBE WHILE INSERTING THE BLACK SEPTUM. DOING THIS
WILL RESULT IN LOW READINGS.
.
4.
REACTION:
Break the bottom (grayish white) ampule in the reaction tube by compressing the sides of the
tube. Mix thoroughly by shaking the reaction tube vigorously for 30 seconds. The mixture will bubble and
perhaps foam during this time. Allow the reaction to proceed for 1.5 minutes. Shake the reaction tube again for
30 seconds and let stand for an additional 30 seconds.
DO NOT BREAK THE GREEN AMPULE.
5.
ANALYSIS:
Press the <ON> key once to activate the meter. Ensure the meter is set for the “
F SoiL
mg
.”
program for the sample matrix being tested (See “Selecting a Program” for instructions on how to change
programs.). Once the meter displays “
tUbE
”, insert the reaction tube into the opening at the bottom of the
meter. The hole in the white cap must be lined up with the metal pin extending from the inside of the hole of
the meter. Push the reaction tube all the way into the meter. Press the <READ> key on the face of the meter.
The display will flash the word “
CALC
,” and the results will be displayed in milligrams of water in the sample.
Record the results.
KEEP THE METER AND REACTION TUBE UPRIGHT AT ALL TIMES.
6.
DISPOSAL:
Carefully remove the reaction tube from the meter. Vent the reaction tube by inserting it
completely into the specially designed venting cap unit and remove slowly.
REACTION TUBE AND CAP
MUST BE UPRIGHT AND POINTED AWAY FROM USER AND BYSTANDERS.
Tap the reaction tube
on a hard surface to shake any loose glass to the bottom of the tube, then break the top (green) ampule in the
reaction tube by compressing the sides of the tube. Shake the tube for 15 seconds. After 5 minutes, vent the
tube again. Discard the reaction tube and soil extraction tube as laboratory waste.
DO NOT REMOVE
WHITE CAP.
7.
CALCULATION:
The meter is programmed to display the weight of the water, in
milligrams
, contained in the
sample. Calculate the water content in weight percent using the following equation:
Water in Soil, wt. percent = R/(10S
1
)
where:
R = Meter reading in milligrams of water
S
1
= Weight of soil sample, in grams
