Yelm Fields_Summary of Geotechnical Engineering Services (2)Draft Technical Memorandum
500 Columbia Street NW, Suite 110 • Olympia, Washington 98501 • (360) 791-3178
TO: Todd Sawin, PE, DBIA, LEED™ AP, AHBL, Inc.
FROM: Annabel Warnell, PE, and Calvin McCaughan, PE
DATE: February 5, 2021
RE: Summary of Geotechnical Engineering Services
Yelm School District Field Upgrades
Yelm, Washington
Project No. 1260012.010.011
Introduction
This memorandum summarizes the results of geotechnical engineering services provided by Landau
Associates, Inc. (LAI) in support of the Yelm School District Field Upgrades project in Yelm,
Washington. Geotechnical services were provided in accordance with the scope outlined in LAI’s
October 30, 2020 proposal.
This memorandum has been prepared with information provided by AHBL, Inc. (prime engineer) and
with data collected during LAI’s geotechnical field exploration and laboratory testing programs.
Project Understanding
Yelm Community Schools (project owner) proposes to upgrade athletic fields at Yelm High School
(YHS), located at 1315 West Yelm Avenue, and Ridgeline Middle School (RMS), located at 10605
Carter Street Southeast (sites; Figure 1). Proposed upgrades include resurfacing athletic fields with
artificial turf, including baseball and softball fields at YHS and a track and field at RMS. According to
current project plans, rainwater will be infiltrated into the athletic fields (similar concept to pervious
pavement).
Surface Conditions
The sites currently are developed with athletic fields surfaced with natural grass. The athletic fields
are located adjacent to the main school buildings, portable classrooms, paved parking lots/drive lanes,
and residential neighborhoods. Topography at YHS is generally flat, with gentle slopes to the east.
Parcels to the west and south sit at an elevation 3 to 6 feet (ft) lower than the YHS athletic fields.
Topography at RMS rises gently to the east. A 30- to 60-ft-tall ridgeline is located along the western
boundary of the RMS campus.
Geologic Conditions
Geologic information for the sites was obtained from the Geologic Map of the Centralia Quadrangle,
Washington (Schasse 1987). Surficial deposits at the sites are mapped as Vashon-age outwash gravel
(Qgog), a unit that generally consists of sand or gravel with locally variable cobble and boulder
content.
DRAFT Landau Associates
Summary of Geotechnical Engineering Services
Yelm School District Field Upgrades 2 February 5, 2021
The soils observed in LAI’s January 2021 explorations were generally consistent with the mapped
geology.
Subsurface Conditions
Subsurface conditions were explored on January 15, 2021 by excavating four test pits (TP-1 through
TP-4) at RMS and five test pits (TP-5 through TP-9) at YHS. Howard’s Construction and Excavating,
subcontracted by LAI, excavated the test pits 8.9 to 10.0 ft below ground surface (bgs). The
approximate locations of the explorations are shown on Figures 2 and 3.
LAI personnel monitored the explorations, collected representative soil samples, maintained a
detailed record of the subsurface soil and groundwater conditions observed, and described the soil by
visual and textural examination. Each representative soil type was described using the soil
classification system shown on Figure 4, in general accordance with ASTM International (ASTM)
standard test method D2488, Standard Practice for Description and Identification of Soils (Visual-
Manual Procedures). Summary logs of the subsurface soil and groundwater conditions are presented
on Figures 5 through 9.
The soils observed underlying existing surface conditions (i.e., grass/sod and topsoil) were categorized
into two general units:
• Fill: Fill was observed in YHS test pits TP-6 through TP-9 and consisted of gravel with variable
silt, sand, and cobble content or of sand with silt and gravel. This unit was observed in a
medium dense to dense, moist condition and extended 1.1 to 5.3 ft bgs.
• Glacial Outwash: Glacial outwash was observed beneath existing surface conditions or fill in
all of the explorations. This unit consisted of gravel with variable sand, silt, and cobble content
in a medium dense to very dense, moist to wet condition. All explorations were terminated in
this unit.
Groundwater was observed from 6.9 to 7.9 ft bgs in RMS test pits TP-1 through TP-4. Slow, perched
groundwater seepage was observed at 1.7 ft bgs in YHS test pit TP-5, but no true groundwater table
was observed. Groundwater conditions will vary depending on local subsurface conditions, weather
conditions, and other factors. Furthermore, site groundwater levels are expected to fluctuate
seasonally, with maximum levels occurring during late winter and early spring.
Geotechnical Laboratory Testing
Samples collected from the test pit explorations were transported to LAI’s soils laboratory for further
examination and testing. Natural moisture content determinations were performed in accordance
with ASTM standard test method D2216, Standard Test Methods for Laboratory Determination of
Water (Moisture) Content of Soil and Rock by Mass. The natural moisture content is shown as W = xx
(i.e., percentage of dry weight) in the "Test Data" column on Figures 5 through 9.
DRAFT Landau Associates
Summary of Geotechnical Engineering Services
Yelm School District Field Upgrades 3 February 5, 2021
Grain size analyses were performed in accordance with ASTM standard test method D6913, Standard
Test Methods for Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis. Samples selected
for grain size analysis are designated with a “GS” in the “Test Data” column on Figures 5 through 9.
Test results are shown on Figures 10 and 11.
Conclusions and Recommendations
Surficial soil at both sites is granular and well suited for stormwater infiltration, provided there is
adequate separation between the bottoms of the aggregate storage layers and the groundwater
table. LAI used the permeable pavement specifications in the 2016 DDECM to develop
recommendations for the proposed field upgrades.
During LAI’s January 2021 field investigation, groundwater levels at RMS were as shallow as 6.9 ft bgs.
Volume V, Section 2.2.6.8.1 of the 2016 DDECM requires a minimum separation of 1 ft between the
seasonal high groundwater level (SHGL) and the bottom of the aggregate storage layer. Based on the
granular nature of the glacial outwash soils at RMS, it is LAI’s opinion that there will be adequate
separation between the SHGL and the base of the storage layer.
Infiltration Feasibility
The design infiltration rates in Table 1 were calculated using the soil grain size analysis method in
Appendix III-A of Thurston County’s 2016 Drainage Design and Erosion Control Manual (2016 DDECM)
and the results of LAI’s geotechnical laboratory testing. Infiltration rates calculated using the grain size
method are intended for soils that have not been compacted by glacial advance or heavy machinery;
soil compaction may reduce infiltration.
Groundwater was not observed at YHS during LAI’s January 2021 field investigation. Based on LAI’s
review of the Washington State Department of Ecology’s well reports (accessed February 2, 2021), a
SHGL of 15 ft bgs was selected to estimate design infiltration rates.
Correction factors were applied to the field infiltration rates in accordance with the 2016 DDECM to
account for facility aspect ratios (CFaspect = 1.4 for RMS and 1.2 for YHS). Per Volume V, Section
2.2.6.4.3 of the 2016 DDECM, a correction factor (Faggregate = 0.9) should be applied to design
infiltration rates if the aggregate storage layer exhibits a fines content that exceeds 1 percent material
passing the U.S. standard No. 200 sieve. The correction factor to account for biofouling and siltation
effects (CFsilt/bio) was not applied to the field infiltration rates, as is appropriate for permeable
pavement. When developing design infiltrates rates, LAI assumed a storage layer water depth (Dpond)
of 6 inches and a separation between the base of the storage layer and SHGL (Dwt) of 5.0 ft bgs at RMS
and 13.0 ft bgs at YHS.
DRAFT Landau Associates
Summary of Geotechnical Engineering Services
Yelm School District Field Upgrades 4 February 5, 2021
Table 1. Design Infiltration Rates
Test Pit Designation
Design Infiltration Rate
(Factored)
(in/hr)
TP-1 3.7
TP-2 0.3
TP-3 0.3
TP-4 0.3
TP-5 0.7
TP-6 0.5
TP-7 0.5
TP-8 1.4
TP-9 4.4
in/hr = inches per hour
The aggregate storage layer will consist of permeable media that spreads infiltrated water laterally. As
such, LAI recommends using an average infiltration rate at each site; this rate should exclude outliers.
LAI recommends a long-term design infiltration rate of 0.3 inches per hour (in/hr) at RMS and a rate
of 0.7 in/hr at YHS.
Use of This Technical Memorandum
Landau Associates has prepared this technical memorandum for the exclusive use of AHBL, Inc.; Yelm
Community Schools; and their designated representatives for specific application to the Yelm School
District Field Upgrades project in Yelm, Washington. No other party is entitled to rely on the
information, conclusions, and recommendations included in this document without the express
written consent of Landau Associates. Reuse of the information, conclusions, and recommendations
provided herein for extensions of the project or for any other project, without review and
authorization by Landau Associates, shall be at the user’s sole risk. Landau Associates warrants that,
within the limitations of scope, schedule, and budget, its services have been provided in a manner
consistent with that level of skill and care ordinarily exercised by members of the profession currently
practicing in the same locality, under similar conditions as this project. Landau Associates makes no
other warranty, either express or implied.
DRAFT Landau Associates
Summary of Geotechnical Engineering Services
Yelm School District Field Upgrades 5 February 5, 2021
Closing
We trust that this memorandum provides you with sufficient information to proceed with the project.
If you have questions or comments, or if we can be of further service, please contact Annabel Warnell
at (360) 791-3178 or at awarnell@landauinc.com.
LANDAU ASSOCIATES, INC.
Annabel Warnell, PE
Project Engineer
Calvin McCaughan, PE
Principal
AMW/CAM/mcs
[Y:\1260\012.010\R\YELM SCHOOL DISTRICT FIELD UPGRADES DRAFT TECHNICAL MEMORANDUM 02.05.2021.DOCX]
Attachments: Figure 1. Vicinity Map
Figure 2. Ridgeline Middle School Site and Exploration Plan
Figure 3. Yelm High School Site and Exploration Plan
Figure 4. Soil Classification System and Key
Figures 5 through 9. Logs of Test Pits TP-1 through TP-9
Figures 10 and 11. Grain Size Test Data
References
ASTM. 2003. D420-D5876: Annual Book of Standards. In: Soil and Rock (I). ASTM International. West
Conshohocken, PA.
Ecology. Well Reports. Washington State Department of Ecology. Accessed February 2, 2021. Available
at:
https://appswr.ecology.wa.gov/wellconstruction/map/WCLSWebMap/WellConstructionMapSearc
h.aspx.
Schasse, H.W. 1987. Geologic Map of the Centralia Quadrangle, Washington. Washington Division of
Geology and Earth Resources. Washington State Department of Natural Resources.
Thurston County. 2016. Drainage Design and Erosion Control Manual. Thurston County Water
Resources Division, Department of Resource Stewardship. December.
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Five CornersFive Corners
North YelmNorth Yelm
YelmYelm
Data Source: Esri.
Yelm School District
Field Updgrades
Yelm, Washington
Vicinity Map Figure1
0 0.5 1
Miles
G:\Projects\1260\012\010\011\F01VicMap.mxd 1/26/2021 Yelm High School
!
!
!
!!
!
W a s h i n g t o n
W a s h i n g t o n
Olympia Tacoma Spokane
EverettSeattle
ProjectLocation
Ridgeline
Middle School
Source: Google Earth 2018
Legend
0 100 200
Scale in Feet
Note
1. Black and white reproduction of this color
original may reduce its effectiveness and
lead to incorrect interpretation.
Landau Associates | Y:\CAD\1260\012.010\Ridgeline.dwg | 1/23/2021 6:20 PM | caduser
Yelm School District
Field Upgrades
Yelm, Washington
Ridgeline Middle School
Site and Exploration Plan
Figure
2
Approximate Test Pit Location and DesignationTP-1
TP-4
TP-2
TP-1
TP-3
Source: Google Earth 2018
Legend
0 100 200
Scale in Feet
Note
1. Black and white reproduction of this color
original may reduce its effectiveness and
lead to incorrect interpretation.
Landau Associates | Y:\CAD\1260\012.010\Yelm High School.dwg | 1/23/2021 6:16 PM | caduser
Yelm School District
Field Upgrades
Yelm, Washington
Yelm High School
Site and Exploration Plan
Figure
3
Approximate Test Pit Location and DesignationTP-1
TP-9
TP-8
TP-7
TP-5
TP-6
4Yelm School District
Field Upgrades
Yelm, Washington
1
Approximate water level at time after drilling/excavation/well
AC or PC
CLEAN SAND
FINE-GRAINED SOILPT
OH
CH
Well-graded gravel; gravel/sand mixture(s); little or no fines
MH
OL
CL
ML
SC
Field and Lab Test Data
Soil Classification System
SM
SP(Little or no fines)(More than 50% of material is smaller than No. 200 sieve size)Silty gravel; gravel/sand/silt mixture(s)
Silty sand; sand/silt mixture(s)
Clayey sand; sand/clay mixture(s)
Inorganic silt and very fine sand; rock flour; silty or clayey finesand or clayey silt with slight plasticity
Inorganic clay of low to medium plasticity; gravelly clay; sandyclay; silty clay; lean clay
Organic silt; organic, silty clay of low plasticity
Inorganic silt; micaceous or diatomaceous fine sand
Inorganic clay of high plasticity; fat clay
Organic clay of medium to high plasticity; organic silt
MAJOR
DIVISIONS
Pocket Penetrometer, tsf
Torvane, tsf
Photoionization Detector VOC screening, ppm
Moisture Content, %
Dry Density, pcf
Material smaller than No. 200 sieve, %
Grain Size - See separate figure for data
Atterberg Limits - See separate figure for data
Other Geotechnical Testing
Chemical Analysis
PP = 1.0
TV = 0.5
PID = 100
W = 10
D = 120
-200 = 60
GS
AL
GT
CA
Groundwater
Code
SAMPLER TYPE
Code Description
SW
GC
Sample Depth Interval
Recovery Depth Interval
Sample Identification Number
SAMPLE NUMBER & INTERVAL
TYPICAL
DESCRIPTIONS (2)(3)
Asphalt concrete pavement or Portland cement pavement
USCS
LETTER
SYMBOL(1)
Approximate water level at time of drilling (ATD)
a
b
c
d
e
f
g
h
i
1
2
3
4
5
Clayey gravel; gravel/sand/clay mixture(s)
GRAPHIC
SYMBOL
Drilling and Sampling Key
Description
Portion of Sample Retained
for Archive or Analysis
GM
GP
GW
Poorly graded gravel; gravel/sand mixture(s); little or no fines
Well-graded sand; gravelly sand; little or no fines
Poorly graded sand; gravelly sand; little or no fines
Peat; humus; swamp soil with high organic content
CLEAN GRAVELGRAVEL AND
GRAVELLY SOIL
(Appreciable amount of
fines)
GRAVEL WITH FINES
(Little or no fines)
(More than 50% of
coarse fraction passed
through No. 4 sieve)
SAND AND
SANDY SOIL
COARSE-GRAINED SOIL(More than 50% of
coarse fraction retained
on No. 4 sieve)
3.25-inch O.D., 2.42-inch I.D. Split Spoon
2.00-inch O.D., 1.50-inch I.D. Split Spoon
Shelby Tube
Grab Sample
Single-Tube Core Barrel
Double-Tube Core Barrel
2.50-inch O.D., 2.00-inch I.D. WSDOT
3.00-inch O.D., 2.375-inch I.D. Mod. California
Other - See text if applicable
300-lb Hammer, 30-inch Drop
140-lb Hammer, 30-inch Drop
Pushed
Vibrocore (Rotosonic/Geoprobe)
Other - See text if applicable(More than 50% of material islarger than No. 200 sieve size)SAND WITH FINES
(Appreciable amount of
fines)
HIGHLY ORGANIC SOIL
(Liquid limit greater than 50)
SILT AND CLAY
RK
DB
Rock (See Rock Classification)
(Liquid limit less than 50)
SILT AND CLAY
Wood, lumber, wood chips
GRAPHIC
SYMBOL
Construction debris, garbage
PAVEMENT
ROCK
WOOD
DEBRIS
OTHER MATERIALS TYPICAL DESCRIPTIONS
LETTER
SYMBOL
WD
> 30% and <
> 15% and <
> 5% and <
<
>
_
_
_
_
Primary Constituent:
Secondary Constituents:
Additional Constituents:
Notes: 1. USCS letter symbols correspond to symbols used by the Unified Soil Classification System and ASTM classification methods. Dual letter
symbols (e.g., SP-SM for sand or gravel) indicate soil with an estimated 5-15% fines. Multiple letter symbols (e.g., ML/CL) indicate borderline
or multiple soil classifications.
2. Soil descriptions are based on the general approach presented in the Standard Practice for Description and Identification of Soils
(Visual-Manual Procedure), outlined in ASTM D 2488. Where laboratory index testing has been conducted, soil classifications are based on
the Standard Test Method for Classification of Soils for Engineering Purposes, as outlined in ASTM D 2487.
3. Soil description terminology is based on visual estimates (in the absence of laboratory test data) of the percentages of each soil type and is
defined as follows:
4. Soil density or consistency descriptions are based on judgement using a combination of sampler penetration blow counts, drilling or
excavating conditions, field tests, and laboratory tests, as appropriate.
50% - "GRAVEL," "SAND," "SILT," "CLAY," etc.
50% - "very gravelly," "very sandy," "very silty," etc.
30% - "gravelly," "sandy," "silty," etc.
15% - "with gravel," "with sand," "with silt," etc.
5% - "with trace gravel," "with trace sand," "with trace silt," etc., or not noted.
Soil Classification System and Key
Figure
DRAFT1 inch of sod over dark brown, fine to coarse
SAND with silt and gravel (loose, moist)
(TOPSOIL)
Red-brown, sandy, well-graded, fine to coarse
GRAVEL with cobbles (dense, moist)
(GLACIAL OUTWASH)
-Grades to gray
-Grades to wet
-Grades to with sand
ATD at 6.9 ft
d
d
d
SP-
SM
GWW = 4
GS
S-1
S-2
S-3Elevation (ft)0
2
4
6
8
10
12
14
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-1
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Notes:1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Figure1260012.01 2/2/21 C:\USERS\AWARNELL\DESKTOP\1260012.010.011.GPJ TEST PIT LOGYelm School District
Field Upgrades
Yelm, Washington
Log of Test Pits 5
1 inch of sod over dark brown, gravelly, fine to
coarse SAND with silt (medium dense, wet)
(TOPSOIL)
Dark brown, very sandy, fine to coarse GRAVEL
with silt and cobbles (dense, moist)
(GLACIAL OUTWASH)
-Grades to gray
-Grades to brown, sandy, very dense, and wet
ATD at 7.0 ft
d
d
d
SP-
SM
GP-
GMW = 12
GS
S-1
S-2
S-3Elevation (ft)0
2
4
6
8
10
12
14
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-2
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Test Pit Completed 01/15/21
Total Depth of Test Pit = 8.9 ft.
Test Pit Completed 01/15/21
Total Depth of Test Pit = 9.0 ft.
DRAFT1 inch of sod over dark brown, fine to coarse
SAND with silt and gravel (medium dense, moist
to wet)
(TOPSOIL)
Dark brown, very sandy, fine to coarse GRAVEL
with silt and cobbles (dense, moist)
(GLACIAL OUTWASH)
-Grades to sandy
-Tree roots observed
-Grades to wet
-Lens of sand with trace organics
-Grades to gray-brown and very dense
ATD at 7.3 ft
d
d
d
d
SP-
SM
GP-
GMW = 11
GS
W = 10
GS
S-1
S-2
S-3
S-4Elevation (ft)0
2
4
6
8
10
12
14
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-3
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Notes:1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Figure1260012.01 2/2/21 C:\USERS\AWARNELL\DESKTOP\1260012.010.011.GPJ TEST PIT LOGYelm School District
Field Upgrades
Yelm, Washington
Log of Test Pits 6
1 inch of sod over dark brown, fine to coarse
SAND with silt and gravel (medium dense,
moist)
(TOPSOIL)
Dark brown, very sandy, fine to coarse GRAVEL
with silt and cobbles (dense, moist)
(GLACIAL OUTWASH)
-Grades to gray-brown
-Grades to wet ATD at 7.9 ft
d
d
d
SP-
SM
GP-
GMW = 18
GS
S-1
S-2
S-3Elevation (ft)0
2
4
6
8
10
12
14
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-4
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Test Pit Completed 01/15/21
Total Depth of Test Pit = 9.3 ft.
Test Pit Completed 01/15/21
Total Depth of Test Pit = 8.9 ft.
DRAFT1 inch of sod over gray-brown, gravelly, fine to
coarse SAND with trace organics (loose, moist)
(TOPSOIL)
Dark brown, very sandy, fine to coarse GRAVEL
with silt and cobbles (medium dense, moist to
wet)
(GLACIAL OUTWASH)
-Grades to dense
-Sod and roots observed
-Grades to orange-brown and very dense
Slow Seepage at 1.7 ft
d
d
d
SP
GP-
GM
W = 14
GS
S-1
S-2
S-3Elevation (ft)0
2
4
6
8
10
12
14
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-5
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Notes:1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Figure1260012.01 2/2/21 C:\USERS\AWARNELL\DESKTOP\1260012.010.011.GPJ TEST PIT LOGYelm School District
Field Upgrades
Yelm, Washington
Log of Test Pits 7
1 inch of sod over gray-brown, fine to coarse
SAND with gravel and trace organics (medium
dense, damp to moist)
(TOPSOIL)
Dark brown, very sandy, fine to coarse GRAVEL
with silt and cobbles (dense, moist)
(FILL)
Orange-brown, sandy, fine to coarse GRAVEL
with cobbles (very dense, moist)
(GLACIAL OUTWASH)
d
d
d
SP
GP-
GM
GP
W = 14
GS
S-1
S-2
S-3Elevation (ft)0
2
4
6
8
10
12
14
Groundwater not encountered.
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-6
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Test Pit Completed 01/15/21
Total Depth of Test Pit = 10.0 ft.
Test Pit Completed 01/15/21
Total Depth of Test Pit = 10.0 ft.
DRAFT1 inch of sod over dark brown, fine to coarse
SAND with silt and trace organics (loose, moist)
(TOPSOIL)
Gray, sandy, fine to coarse GRAVEL (dense,
moist)
(FILL)
Dark brown, very sandy, fine to coarse GRAVEL
with silt and cobbles (dense, moist)
Orange-brown, sandy, fine to coarse GRAVEL
with cobbles (very dense, moist)
(GLACIAL OUTWASH)
d
d
d
d
SP-
SM
GP
GP-
GM
GP
W = 17
GS
S-1
S-2
S-3
S-4Elevation (ft)0
2
4
6
8
10
12
14
Groundwater not encountered.
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-7
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Notes:1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Figure1260012.01 2/2/21 C:\USERS\AWARNELL\DESKTOP\1260012.010.011.GPJ TEST PIT LOGYelm School District
Field Upgrades
Yelm, Washington
Log of Test Pits 8
1 inch of sod over dark brown, fine to coarse
SAND with trace organics (loose, moist)
(TOPSOIL)
Dark brown, fine to coarse SAND with silt and
gravel (medium dense, moist)
(FILL)
Gray-brown, sandy, well-graded, fine to coarse
GRAVEL with cobbles (medium dense, moist)
(GLACIAL OUTWASH)
Gray-brown, sandy, fine to coarse GRAVEL with
cobbles (medium dense, moist)
d
d
d
d
SP
SP-
SM
GW
GP
W = 7
GS
S-1
S-2
S-3
S-4Elevation (ft)0
2
4
6
8
10
12
14
Groundwater not encountered.
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-8
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Test Pit Completed 01/15/21
Total Depth of Test Pit = 10.0 ft.
Test Pit Completed 01/15/21
Total Depth of Test Pit = 10.0 ft.
DRAFT1 inch of sod over dark brown, fine to coarse
SAND with silt, gravel, and trace organics
(loose, damp to moist)
(TOPSOIL)
Dark brown, fine to coarse SAND with silt,
gravel, and cobbles
(FILL)
Gray-brown, sandy, fine to coarse GRAVEL with
cobbles (dense, moist)
(GLACIAL OUTWASH)
-Grades to very dense
d
d
SP-
SM
SP-
SM
GP
W = 5
GS
S-1
S-2Elevation (ft)0
2
4
6
8
10
12
14
Groundwater not encountered.
Logged By:
Tracked Excavator
Not measured
Howard's Construction and Excav.
CAL
Depth (ft)SAMPLE DATA SOIL PROFILE GROUNDWATER
TP-9
Sample Number& IntervalSampler TypeTest DataGraphic SymbolUSCS SymbolGround Elevation (ft):
Excavation Method:
Excavated By:
Notes:1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Figure1260012.01 2/2/21 C:\USERS\AWARNELL\DESKTOP\1260012.010.011.GPJ TEST PIT LOGYelm School District
Field Upgrades
Yelm, Washington
Log of Test Pits 9
Test Pit Completed 01/15/21
Total Depth of Test Pit = 10.0 ft.
0
10
20
30
40
50
60
70
80
90
100
0.0010.010.1110100
Grain Size Test Data
6 103
Depth
U.S. SIEVE NUMBERS
8
%Coarse
Gravel
2 143/4 2006
Cc = D30
2/(D60* D10)
Cu = D60/D10
1
medium
% Coarse
Sand
finecoarse
4 40420
D10D30
% Fine
Sand
PointPercent Finer by Weight140
PI
% FinesD60
fine
D50
Cc
100
Silt or ClaySand
coarse
60
Grain Size in Millimeters
GravelCobbles
3
U.S. SIEVE OPENING IN INCHES
1.5
% Fine
GravelD100
1/2
ClassificationDepth
3/8
Cu
50
To be well graded: 1 < Cc < 3 and
Cu > 4 for GW or Cu > 6 for SW
LL PL
% Medium
Sand
16
Point
30
HYDROMETER
1.4
9.8
7.2
12.2
13.3
7.7
4.0
6.0
2.8
4.2
4.9
14.6
15.6
15.9
21.6
13.0
13.9
16.6
7.9
9.0
41.5
36.7
27.7
50.6
36.6
31.5
21.0
26.8
10.7
15.3
50
50
50
50
37.5
20.552
16.493
12.31
26.033
14.535
14.123
10.706
7.339
19.337
5.834
5.68
0.662
0.701
0.561
0.299
0.616
0.079
0.13
Sandy, well-graded, fine to coarse GRAVEL (GW)
Very sandy, fine to coarse GRAVEL with silt (GP-GM)
Very sandy, fine to coarse GRAVEL with silt (GP-GM)
Sandy, fine to coarse GRAVEL with silt (GP-GM)
Very sandy, fine to coarse GRAVEL with silt (GP-GM)
2.0
2.0
2.5
4.5
2.5
2.0
2.0
2.5
4.5
2.5
TP-1
TP-2
TP-3
TP-3
TP-4
TP-1
TP-2
TP-3
TP-3
TP-4
2.55
0.34
0.31
0.22
33.35
209.67
94.67
471.42
Figure1260012.01 1/28/21 C:\USERS\AWARNELL\DESKTOP\1260012.010.011.GPJ GRAIN SIZE W/STATSYelm School District
Field Upgrades
Yelm, Washington 10
0
10
20
30
40
50
60
70
80
90
100
0.0010.010.1110100
Grain Size Test Data
6 103
Depth
U.S. SIEVE NUMBERS
8
%Coarse
Gravel
2 143/4 2006
Cc = D30
2/(D60* D10)
Cu = D60/D10
1
medium
% Coarse
Sand
finecoarse
4 40420
D10D30
% Fine
Sand
PointPercent Finer by Weight140
PI
% FinesD60
fine
D50
Cc
100
Silt or ClaySand
coarse
60
Grain Size in Millimeters
GravelCobbles
3
U.S. SIEVE OPENING IN INCHES
1.5
% Fine
GravelD100
1/2
ClassificationDepth
3/8
Cu
50
To be well graded: 1 < Cc < 3 and
Cu > 4 for GW or Cu > 6 for SW
LL PL
% Medium
Sand
16
Point
30
HYDROMETER
8.3
10.6
9.4
3.9
2.0
2.5
2.4
4.8
1.4
4.0
21.5
15.7
15.4
14.0
6.2
13.6
13.6
16.9
11.3
13.0
42.1
37.4
34.1
63.5
46.0
11.9
20.2
19.5
6.0
28.8
50
50
50
75
50
20.064
17.023
13.131
34.441
21.554
10.407
11.083
6.374
26.727
16.861
0.432
0.561
0.604
3.338
8.481
0.103
0.084
0.276
0.5
Very sandy, fine to coarse GRAVEL with silt (GP-GM)
Very sandy, fine to coarse GRAVEL with silt (GP-GM)
Very sandy, fine to coarse GRAVEL with silt (GP-GM)
Sandy, well-graded, fine to coarse GRAVEL (GW)
Sandy, fine to coarse GRAVEL (GP)
3.0
3.0
4.0
2.5
4.5
3.0
3.0
4.0
2.5
4.5
TP-5
TP-6
TP-7
TP-8
TP-9
TP-5
TP-6
TP-7
TP-8
TP-9
0.09
0.28
0.33
1.17
6.67
194.94
261.00
156.51
124.60
43.08
Figure1260012.01 1/28/21 C:\USERS\AWARNELL\DESKTOP\1260012.010.011.GPJ GRAIN SIZE W/STATSYelm School District
Field Upgrades
Yelm, Washington 11