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1 Report
Hydrogeologic & Geotechnical Services
1 Proposed Residential Development
Renton, Washington
1 October 24, 1994
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M.A. Segale, Inc.
1 Manufactured/Modular Home Community
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rG e o E n g i n e e r s File No. 0291-006-T03
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Geo%00 Engineers
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' October 24, 1994
Geotechnical,
1 Geoenvironmental and
Geologic Services
' M.A. Segale, Inc.
Manufactured/Modular Home Community
Post Office Box 88050
1 Tukwila, Washington 98138
Attention: Mr. Dana Warren
' Report
Hydrogeologic& Geotechnical Services
1 Cedar Crest Manufactured Home Community
Renton, Washington
File No. 0291-006-T03
1 INTRODUCTION
1 This report presents the results of our geotechnical engineering services for your proposed
Cedar Crest manufactured home community to be situated within the Segale gravel mine site.
The site consists of approximately 133 acres and is located north of the Maple Valley Road (State
1 Route 169) and south of northeast 3rd Street in Renton, Washington. The site location is shown
on the Site Plan/Vicinity Map, Figure 1.
1 Our understanding of the proposed project is based on discussions with you, our site visits
and our review of the documents provided. We understand that the site will be developed as a
MHC (manufactured home community) with approximately 400 manufactured homes. We also
1 understand that streets and utilities, including sanitary sewer, will be constructed in accordance
with the City of Renton design specifications.
1 We understand that stormwater will be infiltrated on-site using roadway collection,
treatment and infiltration systems. The proposed roadway, treatment and infiltration systems will
1 be located within the transmission line right-of-way and in the east and west portions of the center
of the site. For the purposes of clarity, the infiltration areas have been labeled A, B, and C on
the attached site plan. We further understand that the grades in the proposed infiltration areas
1 will be raised between 5 to 15 feet.
1 Geolingineers,Inc.
6240 Tacoma Mall Blvd.,Suite 318
1 Tacoma,WA 98409
Telephone(206)471-0379
Fax(206)471-0521
Printed an recycled paper
' M.A. Segale, Inc.
October 24, 1994
' Page 2
' SCOPE
The purpose of our services is to evaluate the subsurface conditions at the site as a basis
' for developing geotechnical design criteria and recommendations for the proposed development
of the site, including infiltration of the on-site storm water runoff. Specifically, our scope of
services includes the following:
1. Review the available geologic and hydrologic data relevant to the site.
2. Conduct a geologic reconnaissance of the site area.
3. Evaluate the subsurface conditions at the site by monitoring the excavation of test pits.
4. Obtain soil samples at the proposed locations of the infiltration ponds, as appropriate.
' S. Conduct laboratory tests on select soil samples with respect to storm water infiltration.
6. Provide our opinion with regard to the feasibility of infiltrating storm water runoff at the
proposed locations. This will include infiltration rates for the soils, as appropriate.
' 7. Provide geotechnical recommendations for the proposed earthwork at the site. This will
include criteria for structural fill and compaction, foundation design, cut and fill slopes,
' retaining and subgrade walls, utility trench backfill and roadway subgrade.
DOCUMENT REVIEW
' In addition to the available soil, geologic and hydrologic data for the site area, we reviewed
hydrologic-geotechnical information prepared by Golder Associates, Inc. (GAI).
' SITE CONDITIONS
' SURFACE CONDITIONS
The site is located on the south margin of an upland area north of the Cedar River valley.
The south margin of the site consists of a bluff that forms the north wall of the Cedar River
' valley. The site has been surface-mined for sand and gravel.
Topography at the site generally consists of steep cut slopes along the north, east and west
' margins of the mine area and flat to gently rolling surfaces within the mine. The cut slopes at
the margins of the surface-mine area generally range from 2H to 1V (50 percent) to 11/2 to 1 (75
percent). A natural slope extends down to the Cedar River valley on the south property margin.
' Slopes in this area are generally 80 to 130 percent with localized near-vertical areas.
The existing ground surface of the surface-mine area drains to the north-northwest. The
' extreme southern slope drains to the south. Elevations in the upland area generally range from
about 210 to 330 feet at the top of the bluff to between 230 and 300 feet in the central and north
' portions of the site.
Vegetation at the site varies according to topography. The surface-mined upland areas are
generally sparsely vegetated with grass, brush and occasional alder trees. Areas of denser
' vegetation consisting of heavy underbrush and scattered trees occur along the margins of the
' G e o E n g i n e e r s File No.0291-006-T03
' M.A. Segale, Inc.
October 24, 1994
' Page 3
surface-mine area. Vegetation is well established along the south portion of the property, except
for localized areas of steep slopes.
' Surface water was observed near the center of the site in storm water/silt control structures
at the time of our site investigation. The water appears to be perched on a thin accumulation of
fine soil. Flow from this area is to the west and north via an excavated ditch. The outflow is
' directed to a topographic basin located in the northwest portion of the site.
Water seepage was observed in the topographic basin located in the northwest portion of
the site. The water seepage appears to originate from a perched sandy silt lens within the hillside
slope. The ground water seepage and surface water flow is collected in a drop-structure located
near the center of the basin and discharged to the pond/drainage channel located in the northwest
corner of the site.
Based on our previous work at the site and our recent site reconnaissance, no significant
' ground water seepage was observed on the bluff face located at the south margin of the site.
' GEOLOGIC CONDITIONS
General geologic conditions at the site were evaluated by reviewing published and
nonpublished (in-house and outside reports) information, our geologic reconnaissance and
excavating 21 test pits at the approximate locations shown on the site plan. Logs of our field
explorations and laboratory results are presented in Figures 3 through 14. Subsurface conditions
' are described in detail in the Subsurface Conditions section of this report.
The site is located on the southern margin of the Coalfield Drift Upland, a broad glacial
outwash plain. Soils at the site generally consist of fine to coarse-grained recessional and
advance glacial outwash over older pre-Vashon glacial and inter-glacial deposits, and Tertiary
bedrock (Eocene and/or Oligocene sedimentary rocks). These deposits have been modified by
' weathering and erosion since the last glaciation and a surficial layer of topsoil has formed over
the native soil deposits.
' The recessional outwash at the site is characterized as discontinuous layers of
unconsolidated loose to medium dense sand and gravel deposited by meltwater from the retreating
glacier(Vashon stade of the Fraser glaciation). Based on the geometry of the recessional deposits
' in the site area, the sands and gravel deposits in this area were likely deposited in/adjacent to a
glacial outwash channel. Recessional deposits at the site contain only minor amounts of silt and
have a moderate to high permeability. Within the pit, most of the recessional material has been
removed. However, it remains in the pit walls and in areas adjacent to the pit.
Glacial till, commonly referred to as "hard pan," consists of very dense silty sand with
variable amounts of gravel, cobbles and boulders. The till is deposited at the base of the glacial
ice as it over-rides the underlying sediments. Till typically has a low permeability. Glacial till
' is reported to occur along the east and west margins of the site and covers most of the upland
G e o E n g i n e e r s File No.0291-006-T03
' M.A. Segale, Inc.
October 24, 1994
' Page 4
' area to the north. It is likely that the outwash stream eroded or removed the Vashon till in the
site area.
' Within the site area, Vashon advance outwash underlies the recessional deposits. The
advance outwash generally consists of dense to very dense fine to medium sand with a variable
gravel content and a trace of silt. Localized lenses of silty sand, sandy silt and clayey silt occur
' within the advance sediments. The Vashon advance sands typically have a moderate
permeability. Variations in fines/gravel content and density may result in perched or concentrated
' ground water conditions.
Glaciofluvial/interglacial silty sand, sandy silt and clayey silt underlies the Vashon advance
sediments. These sediments were over-ridden by the glacier and are generally in a very dense
' condition. They typically have a low permeability.
Older glacial sediments and Tertiary bedrock material are exposed along the lower
' elevations of the southern bluff, where the Cedar River bisected the upland area after the last
glacial ice retreat from the area. Undifferentiated pre-Vashon glacial and interglacial deposits
were observed along most of the southern bluff slope. These soils generally consist of older
glacial outwash and till, and interbedded silt, silty sand and fine sand. These older soils are
glacially consolidated and have a very low permeability. Based on our review of the available
' boring data at the site and the elevations of the older soil exposures in the bluff, the surface of
these soils appears to slope to the north-northwest.
' SLOPE STABILITY
In general, the native soils at the site consist of medium dense to dense recessional outwash
over very dense glacially consolidated pre-Vashon sediments and bedrock. These materials are
generally stable relative to deep-seated failure and appear to be stable in their existing condition.
' The undisturbed glacially consolidated soils at the site have very high strengths and are stable at
very steep (3/a to 1 and steeper) slopes.
' We previously evaluated the slope stability of the south bluff area. The results of our
evaluation are presented in our March 7, 1994 report. No evidence of deep-seated slope failure
was observed.
' Weathering, erosion, and the resulting surficial sloughing and shallow landsliding are
natural processes that affect steep slope areas. Instability of this nature is confined to the upper
' weathered or disturbed zone which has lower strength. Significant weathering typically occurs
in the upper 2 to 3 feet and is the result of oxidation, root penetration, wet/dry cycles, and
freeze/thaw cycles. Erosion in steep slope areas can be reduced and/or managed through proper
' design and construction of the development. This may include proper drainage control and/or
retention/catchment systems. Erosion control recommendations for the slope areas are provided
' in the Setbacks, and Erosion and Sediment Control sections of this report.
G e o E n g i n e e r s File No.0291-006-T03
M.A. Segale, Inc.
October 24, 1994
Page 5
' SUBSURFACE CONDITIONS
Subsurface conditions at the site were explored by excavating 21 track-hoe test pits,
reviewing 6 borehole logs and pump test data, and reviewing 13 water well logs from Ecology
' files.
Our test pits were excavated to depths of 6 to 20 feet below the existing ground surface.
' The locations of the test pits were selected based on the site map provided, which showed the
planned location of the infiltration systems. The explorations were located in the field by pacing
' from existing features. The approximate locations of the test pits are shown on the Site
Plan/Vicinity Map, Figure 1.
The test pits were monitored by a representative from our firm. Soils encountered were
1 examined and classified, and soil samples were obtained from immediately below the proposed
pond bottom elevations. Soils encountered in the explorations were classified in general
' accordance with ASTM D-2488, the Standard Practice for the Classification of Soils (Visual-
Manual Procedure). A description of this soil classification system is given in Figure 2. Logs
' of the explorations are included as Figures 3 through 11.
Soil samples obtained at the planned pond-bottom elevation were tested to determine their
gradation. The gradation curves are presented as Figures 11 through 14.
' In addition to our subsurface explorations, we reviewed the data from 6 test borings
completed at the site in 1988. The borings ranged in depth from 25 feet to 99 feet below the
' ground surface. Monitoring wells were constructed in borings 1,2 3, 4 and 6. A pump test
performed on well 6 with well 4 used as an observation well. An extraction slug test was
conducted in well 2.
The soils in the site area consist of Vashon recessional glacial outwash, erosional remnants
of Vashon glacial till and Vashon advance outwash which overly older interglacial and glacial
' soils and Tertiary bedrock.
The soils encountered in the explorations located in the old surface-mine bottom consist
primarily of medium dense to dense Vashon advance sand with a variable silt content and
' localized variations in the gravel content. Localized and discontinuous lenses of silt and silty
sand were frequently encountered in the test pits. The lenses ranged from a few inches to a foot
' or more in thickness. Ground water was typically perched on the lenses.
Sandy fine gravel with a trace of silt was encountered in test pit 3 from the ground surface
to a depth of about 7 feet where it is underlain by sand with a trace of silt. Sandy fine gravel
and gravel with a trace of sand was encountered in test pits 15 through 17 to the full depths of
the test pits, 8, 91h, and 81h feet, respectively. Significant ground water flow was observed in
' the gravel units at depths of about 6 to 8 feet.
Older interglacial soils were encountered in the test pits in the central portion of the site.
' In test pits 8 and 9, partially cemented silty fine sand over hard silt with clay were encountered
below the advance sands. The silty sand was encountered at depths of 11 and 16 feet,
' G e o E n g i n e e r s File No.0291-006-T03
M.A. Segale, Inc.
October 24, 1994
Page 6
' respectively. In test pit 21, very stiff silt with clay was encountered at a depth of about 3 feet
and extended to 7 feet where it is underlain by very stiff sandy silt.
' Ground water seepage was encountered in most of the test pits. The seepage ranged from
very slight to significant. The small zones of perched ground water seepage on silty lenses was
generally slight to moderate. The ground water seepage in the gravel units was significant. We
' understand that static water level in the monitoring wells located near the center of the site (4 and
5) was at 3 feet and 5 feet below the ground surface, respectively, on November 11, 1988.
' The borings encountered approximately 75 feet of Vashon advance sands. Below the
advance sands, glaciofluvial and interglacial silty sand, silt and clayey silt were encountered,
borings 3 and 5. Borings 4 and 5, drilled near the central portion of the site, encountered lenses
of silty sand, sandy silt and clay at 18'h and 251h feet, respectively. These silty units likely
correlate with the silty units encountered in test pits 7, 8, 9 and 21.
Ground water levels measured in the monitoring wells in November of 1987 were within
several feet of the ground surface.
' Ground Water Systems
There are records for 13 existing water wells located within 1 mile of the site. Data from
these water wells, observed ground water seepage and our review of the GAI data constitute the
basis for describing the characteristics of the aquifer system for the site area.
' There appears to be at least two distinct ground water (aquifer) systems within the project
area. The Vashon advance outwash unconfined aquifer and a deeper pre-Vashon aquifer. Water
wells in the area typically remove water from the deeper pre-Vashon confined aquifer. Several
' City of Renton wells are located about 1 mile southwest of the site and withdraw water from the
deeper pre-Vashon confined aquifer. In addition, several wells located south of the site in the
Cedar River Valley remove water from the shallow alluvial sediments. Providing that at least
50 percent of the surface water is recharge on site, it is our opinion that there will be no decrease
in water available for withdrawal at the several wells and shallow water system.
' The Vashon advance aquifer in the site area consists of stratified sand and gravelly sand
deposited during the southward advance of glacial ice. These deposits are interbedded with
' localized relatively low-permeability zones of silt and clay. This aquifer is a source of water for
a surface water system (spring) located west of the site. This aquifer is largely unconfined (an
' unsaturated zone exists between the base of the overlying till, where present, and the water level
within the aquifer). The thickness of the saturated zone is influenced by the relief of the surface
of the underlying older deposits and by horizontal and vertical variations in permeability. These
permeability variations are related to zones of soil containing variable amounts of silt and clay
or significant changes in density.
' G e o E n g i n e e r s File No.0291-006-T03
M.A. Segale, Inc.
October 24, 1994
Page 7
We understand that a private water system, for irrigation purposes only, is located west of
the northwest corner of the site. The water system is situated within the natural drainage channel
' that leaves the site and is fed, at least partially, by spring flow. The water system is reported
to have a water rights claim for 250 gpm (gallons per minute).
Ground Water Flow Patterns
Ground water flow patterns have both vertical and horizontal components. In the site area,
the primary vertical component of flow is downward percolation through the recessional outwash
and till, where present, and into the advance outwash aquifer. Some portion of the water likely
infiltrates through the underlying silty sediments and to deeper pre-Vashon aquifer systems.
The horizontal ground water flow pattern in the site area is controlled by less permeable
or confining zones within and/or below the aquifer, the direction of dip or slope of the confining
surfaces, hydraulic head, and both the regional and local topography. As previously discussed,
the projected surface slope of the glaciofluvial/interglacial sediments appears to be to the
northwest. Infiltrated water or ground water in this area would, therefore, flow to the northwest,
at least locally. This is also supported by the lack of evidence of significant ground water
seepage occurring on this portion of the bluff face.
' Based on our geologic reconnaissance and our review of the well logs in the site area, the
ground water flow direction for the Vashon advance outwash aquifer at the site is to the west.
' The hydraulic gradient, or slope on the ground water surface, at the site is reported to be on the
order of 0.01 to west.
' Ground Water Recharge
The recharge to the overall aquifer system is by direct precipitation and infiltration over the
entire upland area. Under existing conditions,precipitation that falls on the site rapidly infiltrates
into the granular soils and recharges the aquifer systems. As the site is developed, potential
changes in the surface coverage could modify the infiltration patterns at the site.
The proposed development plans include infiltration of the storm water runoff from
impervious surfaces at the site through designed infiltration system. Although local changes in
the infiltration pattern and shallow ground water flow may occur, no net change in the overall
ground water recharge or flow direction is expected as a result of the proposed site development.
Water collected from the roadways will be treated in accordance with regulation
requirements and then infiltrated through designed systems.
' CONCLUSIONS AND RECOMMENDATIONS
Based on our data review, site reconnaissance and subsurface explorations, it our opinion
that the site is suitable for the proposed development. No changes in ground water recharge or
flow direction at the site are expected as a result of the proposed development. Precipitation that
G e o E n g i n e e r s File No.0291-006-T03
' M.A. Segale, Inc.
October 24, 1994
Page 8
' currently falls on the site infiltrates rapidly into the granular soils that cover most of the site. As
the site is developed, the amount of impervious surface area at the site will increase. Storm
' water runoff from these areas will be collected and diverted to designed infiltration systems that
will maintain the current infiltration levels at the site. The amount of water infiltrated at the site
will not change significantly,however, the infiltration area or pattern will change. Although this
' may affect the local shallow ground water flow patterns, no significant adverse impact is
expected.
' Currently, a base flow of ground water is collected in a topographic basin located in the
northwest portion of the site, and conveyed off-site. To maintain the existing site water balance,
this discharge must be maintained. The proposed infiltration systems will provide adequate
' recharge to maintain the water balance in the area and maintain the downstream 250 gpm spring
flow.
Slopes located on the site are stable relative to deep seated failure and will not be affected
by the proposed development provided our recommendations are incorporated into the
development plans. The areas of erosion and surficial ravelling and sloughing that occur at the
site are the result of natural processes.
The proposed structures can be satisfactorily supported on medium dense to dense native
' soils or on adequately compacted structural fill in conformance with the manufactures' guidelines.
Building setbacks from the top and toe of slopes and slope setbacks from existing transmission
' line towers are provided in the Setbacks section of this report.
The sand and gravel soils encountered at the site are suitable for use as structural fill. Silty
soils encountered locally are moisture sensitive and will be difficult to compact during wet
' weather conditions.
Pertinent conclusions and geotechnical recommendations regarding the design and
' construction of the proposed development are presented below.
' STORMWATER INFILTRATION/GROUND WATER RECHARGE
In our opinion, infiltration of storm water is feasible at the site and will, in effect, maintain
the existing recharge of the ground water system. The advance outwash granular soils should
' have adequate permeability to infiltrate storm water from the site, provided adequate design,
construction and maintenance practices are used.
Storm water runoff collected from the drive and roadway areas will be infiltrated after
treatment in accordance with current regulatory requirements. Three infiltration ponds(A, B and
C) will be constructed in the central and west portions of the site. The locations of the ponds are
shown on the Figure 1.
Current plans include raising grades in the portion of the site proposed for storm water
' infiltration. To provide additional filtration of the roadway storm water, we recommend that the
' G e o E n g i n e e r s File No.0291-006-T03
M.A. Segale, Inc.
October 24, 1994
' Page 9
' fill consist of a granular soil material placed as a filter blanket. Typically this consists of medium
to coarse grain sand. Specific grain-size design criteria will be provided at your request.
Storage capacity of the soils and possible ground water mounding during wet weather
conditions may have an impact on the final design of the pond infiltration systems. We
recommend that a select fill material, gravel,be used to provide additional storage capacity above
' the existing water table and enhance infiltration of the storm water.
Storm water infiltration rates for site soils were calculated based on the grain-size
distribution of select soil samples and their corresponding soil textures. The U.S. Department
of Agriculture Textural Triangle provided in the Stormwater Management Manual for the Puget
Sound Basin, published in February 1992, was used to determine the soil textures and the
' infiltration rate.
Representative soil samples were collected at the elevations of the proposed infiltration pond
' bottoms below the filter. The theoretical stormwater infiltration rates for the soil samples
analyzed is about 8 inches per hour. This rate of infiltration would occur until the underlying
soil is saturated and the water table is mounded above the bottom of the pond. When the top of
the mound is above the bottom of the pond, the effective infiltration rate is equivalent to the
dissipation rate of the mound. Important factors affecting the dissipation are the size and shape
' of the infiltration area, depth to the water table, and other factors.
For percolation area B, we calculate a dissipation rate of 4 to 6 inches per hour. Based on
' this, a design percolation rate of 4 inches per hour is recommended.
The dissipation rate for area C is calculated to be 4 inches per hour, and a percolation rate
of 4 inches per hour is recommended. For area A, the dissipation rate is calculated to be
' approximately 2 to 21h inches per hour. In order to increase the effective rate to 4 inches per
hour, we recommend the construction of a gravel infiltration blanket that extends north of the
' infiltration pond. The area of the infiltration blanket should be approximately the same as the
bottom area of the ponds (76,800 sq. ft.) to provide an effective percolation rate of 4 inches per
hour in the pond. We recommend the gravel blanket be 4 feet thick and approximately 100 feet
wide. The base of the gravel should be at the same level as the bottom of the filter blanket.
Extending the gravel blanket north of pond A to the region where gravel was encountered will
' significantly increase percolation and provide a margin of safety. A schematic section is provided
as Figure 15.
' Storm water should be treated in accordance with current regulations prior to infiltration.
We understand that wet ponds will be used for treatment of the stormwater runoff. Suspended
solids could eventually clog the soil and reduce the infiltration rate if allowed to enter the ponds
during construction. Because of the potential for clogging, temporary storage and handling of
surface water ponds should be done until after construction is complete and the site is paved and
' landscaped. Periodic sweeping of the paved areas will help extend the life of the infiltration
system.
' G e o E n g i n e e r s File No.0291-006-T03
' M.A. Segale, Inc.
October 24, 1994
' Page 10
Infiltration of the storm water at the site will match existing recharge conditions at the site
and maintain recharge to the down-gradient water supply system. No adverse impact to the
existing water system is expected. The existing collection and discharge of ground water in the
west portion of the site will be maintained by the proposed storm water collection and infiltration
systems.
SLOPE STABILITY
Based on our field observations, data review, subsurface explorations and experience, we
conclude that the slopes at the site are stable relative to deep-seated failure. No changes in slope
stability are expected as a result of the proposed development. Sloped areas of 11/z to 1 or
steeper are currently experiencing erosion and surficial ravelling and sloughing. If measures
recommended in this report are implemented, these natural processes can be expected to be
retarded and sloped areas stabilized/protected as a result.
SETBACKS
The City of Renton restricts building on slopes of 40 percent or greater. The building
setbacks from the top of slope along the south bluff which we previously provided(ranging from
' 25 to 40 feet from the top of the bluff) can likely be reduced based on your final grading plan
and foundation designs.
In other areas of the site where were structures or roadways are proposed near the toes of
slopes, we recommend that catchment systems/wall be constructed using Ecology blocks or
comparable materials, or that structures be set back a minimum of 8 feet.
' For planning purposes we recommend a setback of 15 feet from the foundation/pole of
existing transmission lines to the top of 11k to 1 cut slopes. Erosion control measures should be
provided to minimize any potential erosion and surficial ravelling. If the slopes are 11h:1 or less,
we believe the potential for erosion is minimal.
EARTHWORK
Site Preparation
' Most of the site area was previously cleared and graded incidental to surface-mining
operations. Remaining vegetated or revegetated areas to be graded should be cleared of
deleterious matter including debris and organic materials. Graded areas should be stripped of any
forest duff and organic-laden soils. Based on our site observations, we estimate that stripping
on the order of 2 or 4 inches will likely be necessary to remove the root zone and surficial soils
containing organics in the vegetated areas of the site. Areas with deeper, unsuitable organics
should be expected in the vicinity of man-made water/silt control structures created incidental to
mining. Stripping depths of up to 1 foot are likely in these areas.
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' M.A. Segale, Inc.
October 24, 1994
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' If the clearing operations cause excessive disturbance, additional stripping depths may be
necessary. Disturbance to a greater depth should be expected if site preparation work is done
during periods of wet weather.
The organic-laden strippings can be stockpiled on-site and later used for landscaping
purposes. Materials which cannot be used for landscaping should be removed from the project
site.
Following stripping and prior to placement of fill, the exposed subgrade areas should be
compacted to a firm and unyielding surface. In fill areas, we recommend that trees be removed
' by overturning so that a majority of the roots are removed. Excavations for tree stump removal
should be backfilled with structural fill compacted to the densities described in the Structural Fill
section.
We recommend that the exposed subgrade conditions be evaluated after removal of
vegetation and topsoil stripping is completed and prior to placement of structural fill. The
exposed subgrade soil should be proofrolled with heavy rubber-tired equipment during dry
weather or probed with a 1/2-inch-diameter steel rod during wet weather. Silty surficial soils in
' the vicinity of the drainage swale should not be proofrolled if they contain excessive moisture.
Any soft, loose or otherwise unsuitable areas delineated during proofrolling or probing
' should be recompacted, if practical, or overexcavated and replaced with structural fill, based on
the recommendations of our site representative.
Structural Fill
All new fill material used to achieve design grades within the building and roadway areas
' should be placed as structural fill. The structural fill should be placed in horizontal lifts of
appropriate thickness to allow adequate and uniform compaction of each lift. Fill placed in the
building and pavement areas should be compacted to at least 95 percent of MDD (maximum dry
density as determined in accordance with ASTM D-1557). The appropriate lift thickness will
depend on the fill characteristics and compaction equipment used.
The suitability of material for use as structural fill will depend on the gradation and
moisture content of the soil. As the amount of fines (material passing No. 200 sieve) increases,
soil becomes increasingly sensitive to small changes in moisture content and adequate compaction
becomes more difficult to achieve. During wet weather, we recommend use of well-graded sand
and gravel with less than 5 percent passing the No. 200 sieve based on that fraction passing the
' 3/4-inch sieve.
Material placed for structural fill should be free of debris,organic matter, trash and cobbles
greater than 6 inches in diameter. Particle sizes larger than 3 inches should be excluded from
the top 1 foot of fill. The moisture content of the fill material should be adjusted as necessary
' for proper compaction.
' G e o E n g i n e e r s File No.0291-006-T03
' M.A. Segale, Inc.
October 24, 1994
' Page 12
' Suitability of On-Site Materials as Fill
During dry weather construction, any nonorganic on-site soil may be considered for use as
structural fill, provided it meets the criteria described above in the structural fill section and can
' be compacted as recommended. If the material is over-optimum moisture content when
excavated, it will be necessary to aerate or dry the soil prior to placement as structural fill.
' In general, the granular soils (sand and gravel) observed in our test pits and encountered
in the borings with less than 10 percent fines (material passing the No. 200 sieve) may be used
' as structural fill. This material is comparable to commercial "pit run" sand and gravel.
"Cleaner" material, less than 5 percent fines, will be suitable as structural fill during wet weather
conditions. Most of the site soils will likely meet this criteria.
' CUT AND FILL SLOPES
' Temporary cut slopes may be necessary during grading operations. As a general guide,
temporary slopes of 11h to 1 (horizontal to vertical) or flatter may be used for temporary cuts in
the upper 3 to 5 feet of the glacially consolidated soils that are weathered to a loose/medium
' dense condition. Temporary slopes of 1 to 1 or flatter may be used in the unweathered dense to
very dense sands and gravels or till. These guidelines assume that all surface loads are kept at
' a minimum distance of at least one half the depth of the cut away from the top of the slope and
that significant seepage is not present on the slope face. Although no significant seepage is
expected, flatter cut slopes will be necessary if encountered.
We recommend a maximum of 11h to 1 for permanent cut slopes and 2 to 1 for permanent
fill slopes. Where the recommended slopes are not feasible, catchment or retaining structures
' are recommended. In addition, we recommend that new cut slopes of 11h to 1 be covered with
jute mat and hydroseeded.
' Fill placed on slopes that are steeper than 5 to 1 should be "keyed" into the undisturbed
native soils by cutting a series of horizontal benches. The benches should be 11h times the width
of equipment used for grading and a maximum of 3 feet in height. Subsurface drainage may be
irequired in seepage areas, if encountered. Surface drainage should be directed away from all
slope faces. Some minor raveling may occur with time. All new and existing slopes should be
seeded as soon as practical to facilitate the development of a protective vegetative cover or
otherwise protected.
BUILDING FOUNDATIONS
The proposed manufactured/modular homes should be supported in accordance with the
' manufactures' recommendations. Spread footings will likely provide adequate support for the
proposed structures. Footings which bear on dense native soil or on structural fill compacted to
at least 95 percent of the MDD can be designed using an allowable soil bearing pressure of
2,000 psf for combined dead and long-term live loads, exclusive of the weight of the footing and
' G e o E n g i n e e r s File No.0291-006-T03
M.A. Segale, Inc.
October 24, 1994
' Page 13
' any overlying backfill. This value may be increased by one-third for transient loads such as those
induced by seismic events or wind loadings. We recommend a minimum width of 2 feet for
isolated footings and 16 inches for continuous wall footings.
' We expect that specific requirements for stabilizing the manufactured home units will be
required. Based on the type of system used, specific geotechnical criteria can be provided for
' the various systems.
We estimate that settlements of footings designed and constructed as recommended will be
less than 1/2 inch, with differential settlements between comparably loaded footings of 1/2 inch
or less. Settlements will occur essentially as loads are applied. Disturbance of the foundation
subgrade during construction could result in larger settlements than predicted.
LIMITATIONS
' We have prepared this report for M.A. Segale, Inc., the property owner, and their agents
for use in the design of geotechnical parameters and storm water infiltration systems for this
project. Our conclusions and recommendations are based on widely spaced explorations and
' subsurface conditions between the explorations may vary from those reported. Subsurface
conditions should be monitored during construction to evaluate the consistency of soil type and
grain size. It may be necessary to modify the design of the stormwater infiltration systems if soil
conditions differ from those encountered in the test pits. Our report, conclusions and interpreta-
tions should not be construed as a warranty of the subsurface conditions.
Within the limitations of scope, schedule and budget, our services have been executed in
accordance with generally accepted practices in this area at the time this report was prepared.
' No warranty, express or implied, should be understood.
1 . O .
G e o E n g i n e e r s File No.0291-006-T03
M.A. Segale, Inc.
October 24, 1994
Page 14
We appreciate the opportunity to be of service to Segale Business Park. Please call if you
' have questions regarding this report.
Yours very truly,
' o. H k��rQ GeoEngineers, Inc.
4�w o �o f y�
7 7
Brad . Bigg sta
'
o �ql IST9 R�� �ww Engi eering Geol ist STE ti
ONAL SSG
�EXPIRES�
' Gary . Henderson
Principal
tBPB:GWH:vc
Document ID: 0291006R.R
iAttachments
' Twelve copies submitted
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I
�, .'_' `h O FIGURE 1
1
SOIL CLASSIFICATION SYSTEM
GROUP
MAJOR DIVISIONS SYMBOL GROUP NAME
GRAVEL CLEAN GW WELL-GRADED GRAVEL,FINE TO COARSE GRAVEL
COARSE GRAVEL
GRAINED GP POORLY-GRADED GRAVEL
SOILS More Than 50%
of Coarse Fraction GRAVEL GM SILTY GRAVEL
1 Retained WITH FINES
No. 4 Sieve GC CLAYEY GRAVEL
More Than 50% on
Retained on SAND CLEAN SAND SW WELL-GRADED SAND, FINE TO COARSE SAND
No. 200 Sieve
SP POORLY-GRADED SAND
More Than 50%
of Coarse Fraction SAND SM SILTY SAND
Passes WITH FINES
No. 4 Sieve SC CLAYEY SAND
FINE SILT AND CLAY ML SILT
GRAINED INORGANIC
SOILS CL CLAY
Liquid Limit
Less Than 50 ORGANIC OL ORGANIC SILT, ORGANIC CLAY
More Than 50% SILT AND CLAY MH SILT OF HIGH PLASTICITY, ELASTIC SILT
Passes INORGANIC
CH CLAY OF HIGH PLASTICITY, FAT CLAY
No. 200 Sieve
Liquid Limit
50 or More ORGANIC OH ORGANIC CLAY, ORGANIC SILT
' HIGHLY ORGANIC SOILS PT PEAT
NOTES: SOIL MOISTURE MODIFIERS:
1 1. Feld classification is based on visual examination of soil Dry- Absence of moisture, dusty, dry to the touch
in general accordance with ASTM D2488-90.
Moist- Damp, but no visible water
2. Soil classification using laboratory tests is. based on
ASTM D2487-90. Wet- Visible free water or saturated, usually soil is
obtained from below water table
3. Descriptions of soil density or consistency are based on
interpretation of blow count data, visual appearance of
soils, and/or test data.
I `� SOIL CLASSIFICATION SYSTEM
Geo\Engineers FIGURE 2
LOG OF TEST PIT
DEPTH BELOW SOIL GROUP
GROUND SURFACE CLASSIFICATION
(FEET) SYMBOL DESCRIPTION
TEST PIT 1
0.0-9.5 SP Brown fine to medium sand with a trace of silt and occasional gravel(medium dense
to dense,moist to wet)
' Test pit completed at a depth of 9.5 feet on 09/19/94
Moderate ground water seepage observed at approximately 8.0 feet
' Severe caving observed
Disturbed soil sample obtained at a depth of approximately 4.0 feet
TEST PIT 2
' 0.0-6.5 SP Brown fine to medium sand with a trace of silt(medium dense to dense, moist to
wet)
Lenses of fine sand with silt @ 6.0 feet
' Test pit completed at a depth of 6.5 feet on 09/19/94
Moderate ground water seepage observed at approximately 6.0 feet
Severe caving observed
TEST PIT 3
0.0-7.0 SP Brown sandy fine gravel with a trace of silt(medium dense to dense,moist)
7.0- 10.0 SP Brown fine to medium sand with a trace of silt(dense to very dense,moist)
Test pit completed at a depth of 10.0 feet on 09/19/94
No ground water seepage observed
Moderate to severe caving observed
' Disturbed soil sample obtained at a depth of approximately 2.0 feet
1 THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
'Ip- LOG OF TEST PIT
Geo Pe Engineers FIGURE 3
DEPTH BELOW SOIL GROUP LOG OF TEST PIT
GROUND SURFACE CLASSIFICATION
(FEET) SYMBOL DESCRIPTION
TEST PIT 4
0.0-2.0 SP Dark brown fine to coarse sand with a trace of silt and occasional gravel(medium
dense,moist)
2.0-4.5 GP Dark brown sandy gravel with a trace of silt(medium dense to dense,moist)
4.5 - 12.0 SP Dark brown fine to medium sand with a trace of silt(dense to very dense,wet)
Test pit completed at a depth of 12.0 feet on 09/19/94
Slight ground water seepage observed at approximately 4.0 feet
Severe caving observed
Disturbed soil sample obtained at a depth of approximately 3.0 feet
TEST PIT 5
0.0- 14.0 SP Brown fine to medium sand with a trace of silt(medium dense to very dense,moist)
Test pit completed at a depth of 14.0 feet on 09/19/94
' No ground water seepage observed
Severe caving observed
TEST PIT 6
0.0- 15.5 SP Brown fine to medium sand with a trace of silt and occasional gravel(medium dense
to very dense,moist to wet)
Test pit completed at a depth of 15.5 feet on 09/19/94
Slight ground water seepage observed at approximately 5.5 and 11.0 feet
Severe caving observed
THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
LOG OF TEST PIT
Geo k.qpa Engineers FIGURE 4
LOG OF TEST PIT
DEPTH BELOW SOIL GROUP
GROUND SURFACE CLASSIFICATION
(FEET) SYMBOL DESCRIPTION
TEST PIT 7
0.0-3.0 SP-SM Brown gravelly fine to medium sand with silt(medium dense,moist)
3.0-6.5 SP Brown fine to medium sand with a trace of silt(dense,moist)
6.5-8.0 SM Gray silty fine sand(dense to very dense,wet)
8.0- 18.5 SP Gray fine sand with a trace of silt(dense to very dense,wet)
Test pit completed at a depth of 18.5 feet on 09/19/94
Slight ground water seepage observed at approximately 2.0 and 8.0 feet
' Severe caving observed
TEST PIT 8
0.0-2.0 SP Brown fine to medium sand with gravel and a trace of silt(medium dense,moist)
2.0-7.0 SP Dark gray fine to medium sand with a trace of silt and occasional gravel(dense to
very dense,moist to wet)
7.0- 11.0 SP Brown fine to medium sand with a trace of silt(very dense,moist to wet)
11.0- 13.0 SM Tan silty fine sand(very dense,moist)
13.0- 16.0 ML Bluish gray silt with clay(hard,moist)
Test pit completed at a depth of 16.0 feet on 09/19/94
Very slight ground water seepage observed at approximately 2.0 and 11.0 feet
Moderate caving observed
Disturbed soil sample obtained at a depth of approximately 8.0 feet
THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
LOG OF TEST PIT
Geo op Engineers FIGURE 5
LOG OF TEST PIT
DEPTH BELOW SOIL GROUP
GROUND SURFACE CLASSIFICATION
(FEET) SYMBOL DESCRIPTION
' TEST PIT 9
0.0-3.0 GM Brown gravel with sand and silt(very dense,moist)
3.0- 16.0 SP Brown fine to medium sand with a trace of silt(very dense,moist)
16.0- 17.5 SM Tan silty fine sand(very dense,moist)
17.5-20.0 SM Brown silty sand with gravel(very dense,moist)(cemented)
Test pit completed at a depth of 20.0 feet on 09/19/94
No ground water seepage observed
Minor caving observed
TEST PIT 10
0.0- 1.0 SM Gray silty sand with gravel(very dense,moist)
1.0- 19.0 SP Brown fine to medium sand with a trace of silt(very dense,moist)
Test pit completed at a depth of 19.0 feet on 09/19/94
No ground water seepage observed
Minor caving observed
TEST PIT 11
i0.0-2.5 SP-SM Dark brown fine to coarse sand with silt and gravel(dense,moist)
2.5-6.0 SP Light brown fine to medium sand with a trace of silt(medium dense to dense,moist)
6.0-9.5 SP-SM Gray fine to medium sand with silt(medium dense,moist)
2 foot layer of hay and rotted wood
9.5- 14.0 SP Brown fine to medium sand with a trace of silt and occasional gravel (medium
dense,moist)
' 14.0- 16.5 SP Grades to medium sand(medium dense to dense,wet)
Test pit completed at a depth of 16.5 feet on 10/17/94
Ground water seepage observed at a depth of 14.0 feet
Caving at and below seepage
Disturbed soil sample obtained at a depth of 5.5 feet
THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
LOG OF TEST PIT
Geo &M Engineers
L� *40: FIGURE 6
LOG OF TEST PIT
DEPTH BELOW SOIL GROUP
GROUND SURFACE CLASSIFICATION
(FEET) SYMBOL DESCRIPTION
' TEST PIT 12
0.0-2.7 SP Brown fine to medium sand with gravel and a trace of silt(medium dense to dense,
moist)
2.7-3.5 SP Brown gravelly fine to coarse sand(dense,moist)
3.5-4.5 SP-SM Dark brown fine to medium sand with silt and gravel(dense,moist)
4.5 -6.0 GP Brown sandy gravel(dense,moist)
6.0-9.0 SP Brown gravelly fine to medium sand(dense,moist)
' 9.0- 10.5 SP-SM Gray fine to medium sand with silt partings(dense,moist)
10.5 - 15.0 SP-SM Brown fine to medium sand with gravel and silt partings(dense,moist)
' Test pit completed at a depth of 15.0 feet on 10/17/94
Ground water seepage observed at 14.0 feet
' Caving observed at 14.0 feet
Disturbed soil samples obtained at depths of 2.0,3,0 and 13.5 feet
TEST PIT 13
0.0- 1.5 GP-GM Brown sandy gravel with silt(medium dense,moist)
1.5-3.5 SP Brown medium sand with gravel and a trace of silt(dense,moist)
3.5 4.5 GP-GM Dark brown gravel with silt and sand(dense,moist)
4.5-7.0 SP-SM Light brown fine to medium sand with silt and occasional gravel(dense,moist)
' 7.0- 12.5 SP Gray fine to medium sand with a trace of silt(dense,moist)
3-foot layer of organic material and tree parts
12.5- 13.0 SM Gray fine silty sand(dense,moist)
13.0- 16.0 SP-SM Brown fine to medium sand with silt(dense,moist)
Test pit completed at a depth of 16.0 feet on 10/17/94
No ground water seepage observed
No caving observed
Disturbed soil samples obtained at depths of 4.0,and 5.0 feet
THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
LOG OF TEST PIT
Geo Pw Engineers FIGURE 7
1
LOG OF TEST PIT
i
DEPTH BELOW SOIL GROUP
GROUND SURFACE CLASSIFICATION
(FEET) SYMBOL DESCRIPTION
i TEST PIT 14
0.0- 1.5 GP Brown sandy gravel with a trace of silt(medium dense,moist)
1.5-5.0 SP Brown fine to medium sand with a trace of silt and occasional gravel(dense,moist)
5.0- 15.0 SP-SM Gray fine to medium sand with silt(dense,moist)
i Increasing particle size and decreasing silt content with depth
Grades to wet
i Test pit completed at a depth of 15.0 feet on 10/17/94
Ground water seepage observed at 14.0 feet
i Caving observed at 14.0 feet
Disturbed soil sample obtained at a depth of 3.5 feet
TEST PIT 15
0.0-2.0 SP Light brown fine to medium sand with a trace of silt and occasional gravel(medium
dense,moist)
2.0-8.0 GP Brown sandy gravel(medium dense to dense,moist)
Grades to gravel with a trace of sand(medium dense to dense,wet)
Test pit completed at a depth of 8.0 feet on 10/17/94
Ground water seepage observed at 4.5 feet,with a significant flow at 6.0 feet
Severe caving observed
' Disturbed soil sample obtained at a depth of 5.0 feet
TEST PIT 16
0.0-2.0 SP-SM Brown gravelly fine to medium sand with silt(medium dense,moist)
2.0-9.5 GP Gray sandy gravel(medium dense to dense,moist)
Grades to wet
Test pit completed at a depth of 9.5 feet on 10/17/94
Ground water seepage observed at 8.0 feet
i Severe caving observed
THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
' ��p� LOG OF TEST PIT
Geo no Enggineers
FIGURE S
i
i
LOG OF TEST PIT
i
DEPTH BELOW SOIL GROUP
GROUND SURFACE CLASSIFICATION
(FEET) SYMBOL DESCRIPTION
' TEST PIT 17
0.0-2.5 GP Brown sandy gravel with a trace of silt(medium dense,moist)
' 2.5-5.5 GP Gray sandy gravel(medium dense to dense,moist)
5.5-8.5 GP Brown gravel with sand and a trace of silt(medium dense to dense,wet)
' Test pit completed at a depth of 8.5 feet on 10/17/94
Ground water seepage observed at 8.0 feet
Caving observed at 3.0 feet
TEST PIT 18
' 0.0-6.0 SP Light brown fine to medium sand with occasional gravel and a trace of silt(medium
dense,moist)
iGrades to medium dense to dense,wet)
Grades to wet
' Test pit completed at a depth of 12.0 feet on 10/17/94
Ground water seepage observed at 6.0 feet
' Caving observed at 5.0 feet
TEST PIT 19
0.0-3.0 GP Brown gravel with sand and a trace of silt(medium dense,moist)
' 3.0-8.0 SP Brown fine to medium sand with a trace of silt and occasional gravel (medium
dense,moist to wet)
Test pit completed at a depth of 8.0 feet on 10/17/94
Ground water seepage observed at 6.0 feet
Severe caving observed
i
1
iTHE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
LOG OF TEST PIT
Geoff Engineers FIGURE 9
LOG OF TEST PIT
DEPTH BELOW SOIL GROUP
GROUND SURFACE CLASSIFICATION
' (FEET) SYMBOL DESCRIPTION
' TEST PIT 20
0.0- 1.0 GP Dark brown sandy gravel with a trace of silt(medium dense,moist)
1.0-7.0 SP Brown fine to medium sand with occasional gravel and a trace of silt (medium
dense,moist to wet)
Test pit completed at a depth of 7.0 feet on 10/17/94
' Ground water seepage observed at 6.0 feet
Severe caving observed
TEST PIT 21
' 0.0-3.0 SP Brown fine to medium sand with occasional gravel and cobbles and a trace of silt
(dense to medium dense,moist)
3.0-7.0 ML Gray silt with clay and a trace of sand(very stiff, moist)
7.0- 10.0 ML Gray sandy silt(very stiff, moist)
Test pit completed at a depth of 10.0 feet on 10/17/94
No ground water seepage observed
No caving observed
THE DEPTHS ON THE TEST PIT LOGS,ALTHOUGH SHOWN TO 0.1 FOOT,ARE BASED ON AN AVERAGE OF
MEASUREMENTS ACROSS THE TEST PIT AND SHOULD BE CONSIDERED ACCURATE TO 0.5 FOOT.
LOG OF TEST PIT
Geo\0 Engineers FIGURE 10
= M M Ml M M M M M
o291-o06-T03 BPB:GWH:vc 09/29/94
U.S.STANDARD SIEVE SIZE
31 1.5' 3/4'1 12'31W #4 #10 #20 #40 #60 #100 #200
100
................ .......... ............... ...• . ........ ................... .......... ....................... .................. ....................... ...........
90 ..................... .................................. ............................ ....... ............. .....................
.............
.............. .................
............... ....... ....... ........ .......................
4 Vill
80 ............................... ............................... ............... ................ ................................... ....... ............. ...........................................
Nil OF
urn ...................... ........................ ............... . . ................. . . . .
.............. ... ................................... ........ ....................
70 :.......:.......!.............. ............................... ....... ........
. . . . . . ................. ..................... ....... ............. ......... ....................
0 .......... .............................................. ............. .
... ....................... .... ............................... ............-
W .............. ....................
60 ........*................. ........................................ ................................. '**"*......... .......... .............................
C3
.............. ..................... ..................... ............. ....................
50 ..................... .................... ..................... ..................... .............I.............
........................
U)
............. .................... ............. . .. ....... ....................... ..................... ..................... ......................
.................... ...................................... ...T.......................................... ......................... ...... ..................... .............
W
0
....................... ..................... ........
............. ........................ .............
W
............. ......................
30 ..................... .................... ..................... . ...................
................................... .......................... .................... ......... ............. ............. ............................
....................... ............. ............................... ..................... ................... -------- .......T.............:':'7................ ..............
............................... ................. ............. ..................... ...................................... ....... ............. .......................................
10 ..................i.............................................
............. .... ..
......................... ... ........ ..................... ......
.............. .................... ..............
............. ...................... ....... ............. ......... ........
XI 0
1.000 100 10 1 0.1 0.01 0.001
-n GRAIN SIZE IN MIWMErERS
0 0
C Z GRAVEL SAND
XI COBBLES SILT OR CLAY
M 0 1 COARSE I FINE 1COARSE1 MEDIUM FINE
C
<
M
SYMBOL EXPLORATION SAMPLE
NUMBER DEPTH(FEET)
SOIL DESCRIPTION
0 TP-1 4.0 Fine to medium sand with a trace of silt and occasional gravel
= m m m m m m m m m m m m m m m m m m
0291-006-T03 BPB:GWH:vc 09/29/94
U.S.STANDARD SIEVE SIZE
3' 1.5' 3/4"1/2'3/8' #4 #10 #20 #40 #80 #100 #200
100
.............. ..............................................
............ .......................
................................. .................................
............. .....................
90 ....... ..................... ............................... ............................... ..........................
•
.................... ................... .........I...................... ...................... ..................... .....................
,lla
............. ......I....... ............. ....... ............. ....................
............ ...... ...................
.................... .................. ............. ........... ....................
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10 ........ ..................... .................... ........ ..................... ....................
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z ........................... ...............................
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cr
LU
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0
I I I I I I T I
1,000 100 10 1 0.1 0.01 0.001
-n >
GRAIN SIZE IN MILILIMIFIFERS
C z
:Iu 0 COBBLES GRAVEL SAND
m SILT OR CLAY
C I COARSE I FINE COARSE MEDIUM FINE
rn
SYMBOL EXPLORATION SAMPLE
NUMBER DEPTH(FEET)
SOIL DESCRIPTION
• TP-3 2.0 Sandy fine gravel with a trace of silt
= m m m = m = = m = m m m = m m m m =
0291-006-T03 BPB:GWH:vc 09/29/94
U.S.STANDARD SIEVE SIZE
3. 1.5" 8/4"1/2'3/8" 44 #10 #20 #40 #60 #100 #200
100
............. ..........................
................. ........................... ... .. ............ .....................
............... .........
.......... .......
go . ... .............................
......... ....... .......... ...................... ........ ....... .............
.................... ................................ .............................. .................................... ....... ............. ....... ..... ........
...
80 .................. ............. ............................... ...................... ....... ............. ..................... ........... .............
..................... ................................ ................................. .......................
....................... ............ ..........
70 ..................... .................a........... ..................... ..................... ............................................I.............
... .......
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z
0,) 50 ..................... .................... ..................................................................... ............. ............. .....................
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........... ...................... .......... ............. ............. .................................. ...................................... .........:.............
40 ...............
Lu
.............
ir .............. .................... ........... ........ ....................
a- so ............................... .................... .................... ..................... ....... ............. ......................
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......................
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0 ------------- I-rT-rT-T--r--T-i
> r I
1,000 100 10 1 0.1 0.01 0.001
GRAIN SIZE IN MILLIMETERS
O 0
C z
III COBBLES GRAVEL FINE I COARSE SAND MEDIUM IF SILT OR CLAY
m 0 COARSE I F FINE
C 11
.A m
W <
m EXPLORATION SAMPLE
Cl) SYMBOL NUMBER DEPTH(FEET) SOIL DESCRIPTION
• TP-4 3.0 Sandy gravel with a trace of silt
M M M M M M M M 1=1 M M M M M M M M M M
0291-0o6-T03 BPB:GWH:vc 09/29/94
U.S.STANDARD SIEVE SIZE
3* 1.5- 3/4-1/2-3/8' #4 #10 #20 #40 #60 #100 #200
100
.............. ....... ........................ ......................................
............. ........ .. ............. ...............
............................... ....... ......................... ........ ............. ............................. ....... ............ ........ .....................
................... ........................................ ....... ............... ................................ ..................... ............ .......................
80 .............................. *.........................
i..*1-i...1.4....i.....i.......i...............141.4 1 ......................*,44-4-4 ...........i........i.............i.
...................
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70 ................................. .................................... ...................... ..................... ...................................... ..............................
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.......t ............. ................. .............. ............. ...................... ........ ..................... ................................2 40
................ ........... .......................... ....... ............. .....................
.............
30 ...... ..................... .................... .....................
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0
>
1,000 100 10 1 0.1 0.01 0.001
-n GRAIN SIZE IN MILLIMETERS
0 0
C z
rn 0 GRAVEL SAND COBBLES T_ FINE
SILT OR CLAY
C I COARSE FINE COARSE MEDIUM MEDIUM I
rn EXPLORATION SAMPLE
U) SYMBOL NUMBER DEPTH(FEET)
SOIL DESCRIPTION
40 TP-8 8.0 Brown fine to medium sand with a trace of silt
POND
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FIGURE 15
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