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===Making measurements===
===Making measurements===
# To undertake the test, fill the test hole (the accurately sized test hole) with water. The water should be added carefully and slowly to avoid disturbing the soil (including the sidewall soils). When the water level falls anywhere below the 27.5 cm mark, refill the hole to the top. No recording of time needs be done for these 2 fillings.
# To undertake the test, fill the test hole (the accurately sized test hole) with water. The water should be added carefully and slowly to avoid disturbing the soil (including the sidewall soils). When the water level falls anywhere below the 12.5 cm mark, refill the hole to the top. No recording of time needs be done for these 2 fillings.
# After the second filling, when the water level falls below 27.5 cm, add enough water to bring the depth of water to 15 cm or slightly more. Note that these measurements are from the base of the soil bottom (using the installed marker), not the gravel layer.
# After the second filling, when the water level falls below 12.5 cm, add enough water to bring the depth of water to 15 cm or slightly more. Note that these measurements are from the base of the soil bottom (using the installed marker), not the gravel layer.
# Observe the water level until it drops to the 15 cm depth, at precisely 15 cm, commence timing, when the water level reaches the 12.5 cm depth, stop timing, record the time in minutes.
# Observe the water level until it drops to the 15 cm depth, at precisely 15 cm, commence timing, when the water level reaches the 12.5 cm depth, stop timing, record the time in minutes.
# Repeat the procedure until the last 2 rates of fall do not vary more than 2 minutes or by more than 10% (whichever is less).
# Repeat the procedure until the last 2 rates of fall do not vary more than 2 minutes or by more than 10% (whichever is less).
# Open the tube until the paper is in contact with the sidewalls of the test hole, then roll the top of the tube over to stiffen it.
# Open the tube until the paper is in contact with the sidewalls of the test hole, then roll the top of the tube over to stiffen it.
# After placing the tube in the hole, place the plastic marker and add the base gravel layer.
# After placing the tube in the hole, place the plastic marker and add the base gravel layer.
==References==