SW6221101_Soils/Geotechnical Report_20221129 (12)

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Advanced Skills Training Center - Technical Support Training Annex
PN 79439 FY16
Fort Bragg, NC (Yarborough Complex)
Tests were performed by Forpu Njikam during the period spanning 03 to 04 February 2016
Soil percolation tests were performed in accordance with DM 110-1-1, Jul 83, chapter 20.
Weather Conditions were mostly overcast with sustained rains and a high temperature of 50F over the duration of the testing.
Various lengths of slotted pvc pipe screens were placed in each hole to minimize difficulties associated with hole cave-in, and
2 - 3" of pea gravel was placed in the bottom of the holes before water was added.
Water levels were measured by a water level indicator with reference point on the inserted slotted pipe screen.
A minimum 6" water column above gravel was used as the initial height of water, subsequently recharged to
F this level after each reading as necessary. All times were noted by digital watch and stop watch.
The Michigan method is used to estimate infiltration rates from percolation rates.
The infiltration rate to use for the design of affected ponds and bioswales is in bold print.
An auger boring was advanced to a depth of 25 feet within the proposed footprint of each of the proposed bioswales
in order to determine the Seasonal High Water Table .
The soil profiles observed in the SHWT determination auger borings correlate with the profiles observed in
the corresponding test holes to corresponding depths.
Percolation Test # PT-1
E I Percolation test hole: 4" diameter x 35.4" (2.9') deep (approx. elev ***)
C
0
Soil profile matches soil boring SHWT-01, SHWT estimated at a depth in excess of 25'
Start and End Timi Elapsed
initial reading
final reading
percolation rate
Infiltration rate
time (min.)
from top of riser, ft
from top of riser, ft
ft/hr
in/hr
Rf
Inf rate (in/hr)
0815
- 0845
30
2.01
2.02
0.02
0.24
17.41
0.01
0845
- 0915
30
2.02
1.97
-0.10
-1.20
17.53
-0.07
0915
- 0945
30
1.97
1.97
0.00
0.00
17.68
0.00
0945
- 1015
30
1.97
1.95
-0.04
-0.48
17.74
-0.03
1015
- 1045
30
1.95
1.95
0.00
0.00
17.80
0.00
**Note** Test was conducted during a rain event. Water rise in test hole could be due to precipitation, Infiltration Rate for this test is 0 in/hr
Percolation Test # PT-2
Percolation test hole: 4" diameter x 48" (4') deep (approx. elev ***)
Soil profile matches soil boring SHWT-02, SHWT estimated at a depth in excess of 25'
Start and End Timi Elapsed
initial reading
final reading
percolation rate
Infiltration rate
time (min.)
from top of riser, ft
from top of riser, ft
ft/hr
in/hr
Rf
Inf rate (in/hr)
0813
- 0843
30
1.95
1.95
0.00
0.00
18.70
0.00
0843
- 0913
30
1.95
1.91
-0.08
-0.96
18.82
-0.05
0913
- 0943
30
1.91
1.87
-0.08
-0.96
19.06
-0.05
0943
- 1013
30
1.87
1.83
-0.08
-0.96
19.30
-0.05
1013
- 1043
30
1.83
1.74
-0.18
-2.16
19.69
-0.11
* *Note * * Test was conducted during a rain event. Water rise in test hole could be due to precipitation, Infiltration Rate for this test is 0 in/hr
Percolation Test # PT-3
Percolation test hole: 4" diameter x 37.2" (3. F) deep (approx. elev ***)
Soil profile matches soil boring SHWT-03, SHWT estimated at a depth in excess of 25'
Start and End Timi Elapsed
initial reading
final reading
percolation rate
Infiltration rate
time (min.)
from top of riser, ft
from top of riser, ft
ft/hr
in/hr
Rf
Inf rate (in/hr)
0905 -
0935
30
1.91
1.88
-0.06
-0.72
18.61
-0.04
0935 -
1005
30
1.88
1.85
-0.06
-0.72
18.79
-0.04
1005 -
1035
30
1.85
1.86
0.02
0.24
18.85
0.01
1035 -
1105
30
1.86
1.89
0.06
0.72
18.73
0.04
1105 -
1135
30
1.89
1.91
0.04
0.48
18.58
0.03
* *Note * * Test was conducted during a rain event. Water rise in test hole could be due to precipitation.
Percolation Test # PT-4
Percolation test hole: 4" diameter x 46.8" (3.9') deep (approx. elev ***)
Soil profile matches soil boring SHWT-01, SHWT estimated at a depth in excess of 25'
Start and End Timi Elapsed
initial reading
final reading
percolation rate
Infiltration rate
time (min.)
from top of riser, ft
from top of riser, ft
ft/hr
in/hr
Rf
Inf rate (in/hr)
0819 -
0849
30
0.94
0.94
0.00
0.00
24.16
0.00
0849 -
0919
30
0.94
0.93
-0.02
-0.24
24.19
-0.01
0919 -
0949
30
0.93
0.93
0.00
0.00
24.22
0.00
0949 -
1019
30
0.93
0.93
0.00
0.00
24.22
0.00
1019 -
1049
30
0.93
0.93
0.00
0.00
24.22
0.00
**Note** Test was conducted during a rain event. Water rise in test hole could be due to precipitation, Infiltration Rate for this test is 0 in/hr
Percolation Test # PT-5
Percolation test hole: 4" diameter x 62.4" (5.2') deep (approx. elev ***)
Soil profile matches soil boring SHWT-02, SHWT estimated at a depth in excess of 25'
Start and End Timi Elapsed
initial reading
final reading
percolation rate
Infiltration rate
time (min.)
from top of riser, ft
from top of riser, ft
ft/hr
in/hr
Rf
Inf rate (in/hr)
0820 -
0850
30
3.75
3.78
0.06
0.72
21.01
0.03
0850 -
0920
30
3.78
3.80
0.04
0.48
20.86
0.02
0920 -
0950
30
3.80
3.82
0.04
0.48
20.74
0.02
0950 -
1020
30
3.82
3.85
0.06
0.72
20.59
0.03
1020 -
1050
30
3.85
3.87
0.04
0.48
20.44
0.02
"Note" * * Test was conducted during a rain event.
Percolation Test # PT-06
Percolation test hole: 4" diameter x 36" (3') deep (approx. elev ***)
Soil profile matches soil boring SHWT-03, SHWT estimated at a depth in excess of 25'
Mart and End Time Elapsed
initial reading
final reading
percolation rate
Infiltration rate
time (min.)
from top of riser, ft
from top of riser, ft
ft/hr
in/hr
Rf
Inf rate (in/hr)
0822 -
0852
30
2.49
2.48
-0.02
-0.24
9.49
-0.03
0852 -
0922
30
2.49
2.48
-0.02
-0.19
9.50
-0.02
0922 -
0952
30
2.48
2.49
0.02
0.24
9.49
0.03
0952 -
1022
30
2.49
2.52
0.06
0.72
9.37
0.08
1022 -
1052
30
2.52
2.50
-0.04
-0.48
9.34
-0.05
* *Note * * Test was conducted during a rain event. Water rise in test hole could be due to precipitation, Infiltration Rate for this test is 0 inlhr
NOTES:
1. FOR CHART AND NOTES,
REFER TO PLATE B-001.
3. FOR SOIL TEST BORING
LOCATIONS, REFER TO
PLATE B-100.
US Army Corps
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