BCOM2022-0026 Geotechnical ReportGEOTECHNICAL REPORT
46805 Dune Palms Road
BCOM2022-0026 La Quinta, California
CITY OF LA QUINTA
BUILDING DIVISION
REVIEWED FOR
CODE COMPLIANCE
BY: A /1 ,,,, DATE: 07111912022
SHELL BUILDING REMODEL
WITH 1,963SF ADDITION TO
2ND LEVEL FLOOR AREA
[ENGINEERED] THIS PERMIT
DOES NOT INCLUDE FULL
BUILD OUT OF INTERIOR
TENANT SPACES OR
APPROVAL FOR P4 rket
OCCUPANCY. TEN
IMPROVEMENTS AND PATH
OF TRAVEL ACCESSIBILITY
December 8, 2021
Project No. 4969
Prepared for
ROFE
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* EXP. 12/31 /23
Street Development, LLC
by
UPGRADES ARE PART O THE PHASED APPROVAL Gularte & Associates, Inc.
AND WILL BE DETERMINED
PRIOR TO FINAL
OCCUPANCY 2019
CALIFORNIA BUILDING
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u I a rte 1049 NICHOLS DRIVE, RgOCKLIN, CA 95765
& ASSOCIATES, INC. ,:"N,� Phone: 916.626.5577
Geotechnical Consultants w'�� FAX: 916.626.5533
1
TABLE OF CONTENTS
1 INTRODUCTION...........................................................................................3
2 LOCATION, SITE DESCRIPTION AND PHYSICAL SETTINGS ..................4
2.1 SITE LOCATION....................................................................................4
2.2 SITE DESCRIPTION..............................................................................4
2.3 PHYSICAL SETTINGS...........................................................................4
2.3.1 Regional Geology..............................................................................4
2.3.2 Local Geology...................................................................................5
2.3.3 Faults and Seismicity.......................................................................5
2.3.4 Groundwater......................................................................................7
2.3.5 Geologic Hazards..............................................................................7
3 FINDINGS AND CONCLUSIONS.................................................................8
3.1 SUBSURFACE CONDITIONS...............................................................8
3.2 LABORATORY ANALYSES..................................................................8
3.3 EXISTING FILL......................................................................................9
3.4
EXISTING ASPHALT CONCRETE PAVEMENT...................................9
3.5
EXISTING FOOTING DIMENSIONS......................................................9
3.6
EXCAVATION EFFORT.......................................................................10
3.7
SUITABILITY FOR CONSTRUCTION.................................................10
4 EARTHWORK RECOMMENDATIONS.......................................................11
4.1
NATIVE AND IMPORT FILL MATERIAL.............................................11
4.2
FILL COMPACTION.............................................................................11
4.3
TRENCH BACKFILL............................................................................11
4.4
SITE DRAINAGE..................................................................................12
5 FOUNDATION RECOMMENDATIONS.......................................................13
5.1
FOUNDATIONS...................................................................................13
5.2
SLAB ON GRADE................................................................................13
5.3
RETAINING WALL PARAMETERS.....................................................14
5.4
2019 CBC SEISMIC PARAMETERS...................................................15
5.5
PAVEMENT DESIGN...........................................................................16
5.5.1 Asphalt Concrete Pavement for Automobile Parking Areas .......16
5.5.2 Trash Enclosure Concrete Pavement Design...............................16
5.5.3 Special Inspections.........................................................................17
1
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
6 LIMITATIONS..............................................................................................18
FIGURES
Figure 1
—Vicinity Map
Figure 2
— Site Plan
Figure 3
— Geologic Map
Figure 4
— USGS Unified Hazard Curves
Figure 5
— CGS Seismic Hazards Map
APPENDICES
Appendix A — Boring Logs
Appendix B — Laboratory Test Results
Appendix C — Site Photographs
Appendix D — Geotechnical Terms/Definitions
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8. 2021
1 INTRODUCTION
Market Street Development, LLC. has retained Gularte & Associates, Inc. to
perform a geotechnical report for an existing structure at 46805 Dune Palms Road
in La Quinta, California (APN: 600-390-023). The proposed renovation consists of
converting the existing structure into a commercial medical office. To conduct this
geotechnical report, we performed the following services:
Reviewed the site geology and groundwater conditions.
Advanced 3 exploratory soil borings to a maximum total depth of
approximately 50 feet below existing grade to record SPT N-values, classify
the soil profiles, as well as obtain soil samples for laboratory analyses.
Performed 6 moisture -density analyses on tube samples.
Performed 6 sieve wash analyses on disturbed samples.
Reviewed the provided structural drawings (Sheets S1, SD1 and SD2) for
the existing structure, prepared by Robert H. Ricciardi A.I.A. & Associates
and Anderson Structural Engineering, dated January 22, 2003.
Performed engineering analyses and used engineering judgment for
earthwork and foundation recommendations in this report.
Prepared this report with our findings, conclusions, and recommendations.
We recommend that we be retained to review any proposed project grading and
structural plans at the 50 to 90 percent stage for compliance with our report.
3
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
2 LOCATION, SITE DESCRIPTION AND PHYSICAL SETTINGS
2.1 SITE LOCATION
Figure 1 shows the Vicinity Map of the proposed commercial medical office
building project located at 46805 Dune Palms Road in La Quinta, California. The
site is bordered by Dune Palms Road on the east, Corporate Center Drive on the
north, a commercial retail structure on the west, a beauty college on the
southwest, and a fueling station on the southeast.
2.2 SITE DESCRIPTION
The approximatley 1.0-acre parcel is roughly rectangular in shape, with the north -
south axis approximatley 235 feet in length and the east -west axis approximatley
210 feet in length. A project topographic map was not available at the time of this
report. Based on the United States Geological Survey (USGS) Topographic Map
of the La Quinta, California Quadrangle, 2018, 7.5-Minute Series, the average
elevation of the site is approximately 60 feet above mean seal level (MSL). Site
topography relatively level.
An existing 19,846 SF two-story structure with a concrete slab foundation is
located in the southwest portion of the site. Per the provided real estate brochure
for the property, the ground floor space is approximately 15,787 SF and the
second level office and mezzanine space is approximately 4,059 SF. Paved
parking areas and driveways surround the existing structure. Landscaping,
consisting of bushes and mature trees are located within planter areas along Dune
Palms Road and Corporate Center Drive.
Market Street Development, LLC proposes remodeling the existing structure as a
commercial medical office.
2.3 PHYSICAL SETTINGS
2.3.1 Regional Geology
The site is located in the northwestern portion of the triangular -shaped Colorado
Desert province of Southern California. This geomorphic province is bound by the
Peninsular Ranges province on the west, the Mojave Desert province on the east,
the eastern Transverse Ranges province on the north, and Mexico on the south.
The San Andreas Fault follows the northeastern boundary of the province into the
San Gorgonio Pass area. Elevations throughout the province are low and
sometimes extend below sea level. The Colorado Desert province, also known as
the Salton Sink, is a northwest trending, seismically active structural basin that is
undergoing active crustal extension (Sutch & Dirth, 2019). Drainage from the
Coachella Valley to the north and the Imperial Valley to the south drain towards
the Salton Sea in the southern portion of the province. Prehistoric Lake Cahuilla,
evidenced by its ancient shorelines, silt and travertine deposits, occupied the
southern portion of the province during the Pleistocene and Holocene (Norris &
Norris, 1961), but eventually disappeared. The existing Salton Sea formed when a
canal system along the Colorado River failed in 1905 and water overflowed into
the basin.
4
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
2.3.2 Local Geology
The Geologic map of the Palm Desert and Coachella 15-minute Quadrangles,
Riverside County, California, prepared by Dibblee, T.W., Jr., and Minch, J.A.,
2008, was reviewed prior to our subsurface exploration. This source indicates that
the site surface is composed of Quaternary period alluvial sand and clay deposits
(Qa). This interpretation agrees with the predominantly unconsolidated sand and
silty sand observed in the exploratory borings.
2.3.3 Faults and Seismicity
Based on our review of the 2010 Fault Activity Map of California prepared by the
California Geological Survey (CGS), the nearest active faults within a 50-mile
radius of the project site that have historic ruptures or evidence of surface
displacements of Holocene age or younger (i.e. approximatley within the past
11,000 years before present), are presented in Table 1 on the following page. The
USGS Earthquake Scenario Map (BSSC 2014) was also reviewed for published
probable earthquake magnitudes. The site is not located within a currently
established Alquist-Priolo (AP) Earthquake Fault Zone (Figure 5). Existing faults,
active or inactive, are not located on any portion of the project site per CGS.
We used the USGS Unified Hazard Tool to determine the deaggregated seismic
source parameters including controlling magnitude and fault distance. The USGS
estimated modal magnitude is 7.49 and the controlling distance is 8.4 kilometers.
Based on the Structural Engineers Association of California Seismic Design Maps
web tool, the estimated Site Modified Peak Ground Acceleration (PGAM) for the
Maximum Considered Earthquake (MCEG) with a 2,475-year return period is
0.787g.
5
GEOTECHNICAL REPORT
46805 Dune Palms Road - La Quinta, California (APN: 600-390-023)
Job Number. 4969 December 8, 2021
Fault Name
San Andreas Fault Zone
Approximate
■
5.2 WNE
Magnitude
8.18
South Branch San Andreas Fault
5.4 WNE
7.45
North Branch San Andreas Fault
5.5 WNE
7.46
Burnt Mountain Fault Zone
16.9 N-NW
6.72
Eureka Peak Fault
17.7 N-NW
6.61
Long Canyon Fault
18.2 N-NW
-
San Jacinto Fault Zone
20.04 W-SW
7.76
Clark Fault
20.9 W-SW
7.05
Coyote Creek Fault
22.2 S-SW
7.68
Garnet Hill Fault
23.5 W-NW
7.08
Morongo Valley Fault
29.0 N-NW
-
San Gorgonio Pass Fault Zone
29.4 W-NW
6.94
Pinto Mountain Fault
29.8 N-NW
7.27
Johnson Valley Fault Zone
32.3 N-NW
7.07
Copper Mountain Fault
32.4 WNE
7.16
unnamed fault
32.6 SE
-
Mesquite Lake Fault
32.9 WNE
7.27
Hot Springs Fault San Jacinto F.Z.
35.0 W-NW
-
Hot Springs Fault
35.6 E-SE
-
Pisgah -Bullion Fault Zone
35.9 WNE
7.27
Casa Loma Fault
36.8 W-NW
7.31
Emerson Fault
37.6 N-NW
7.16
Homestead Valley Faut Zone
38.6 N-NW
7.02
Calico -Hidalgo Fault Zone
39.9 WNE
7.44
Earthquake Valley Fault
40.1 S-SW
6.74
Brawley Seismic Zone
41.1 E-SE
6.11
Beaumont Plain Fault Zone
42.8 W-NW
-
Elsinore Fault Zone
42.8 S-SW
7.77
Extra Fault Zone
44.0 S-SE
-
unnamed fault
44.7 E-SE
-
Banning Fault
45.4 W-NW
-
North Frontal thrusts stem
46.5 N-NW
7.16
Wildomar Fault
48.5 W-SW
7.69
Elmore Ranch Fault
48.6 S-SE
6.67
Old Woman Springs Fault
48.9 N-NW
7.50
Lenwood-Lockhart Fault Zone
49.0 N-NW
7.50
Table 1 - Regional Fault Summary
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8. 2021
2.3.4 Groundwater
Groundwater was not encountered during our subsurface exploration. Based on
continuous data sets obtained from the California Department of Water
Resources, depth to static groundwater is approximatley 171 feet below ground
surface (bgs) in a monitoring well that is approximately 3,715 feet northwest from
the site. Perched groundwater may be possible during heavy rain events.
2.3.5 Geologic Hazards
The site has not been evaluated by CGS for liquefaction hazards (Figure 5). The
soil profiles in the exploratory boring consisted of sand and silty sand. Considering
the depth to the existing water table, which is approximatley 171 feet bgs, risk of
liquefaction is low. Due to the relatively flat topography at the site, risk from
landsliding and lateral spreading are low.
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN: 600-390-023)
Job Number: 4969 December 8, 2021
3 FINDINGS AND CONCLUSIONS
3.1 SUBSURFACE CONDITIONS
Three exploratory soil borings (B-1 through B-3) were advanced to a maximum
depth of 50 feet bgs to record SPT N-value, classify the soil profiles and obtain
samples for laboratory analyses. The soil borings were located in the concrete
asphalt pavement adjacent to the existing structure (Figure 2). Soil boring logs are
shown in detail in Appendix A.
The findings in the soil borings were fairly consistent across the site. In general,
the soil profiles consisted predominately of pale olive to light brown, medium
dense poorly graded fine grain SAND with silt and Silty SAND to total depth of 50
feet bgs. In the northern portion of the site, medium stiff olive SILT with sand
layers were noted at approximately 15 feet bgs in boring B-2, and from
approximately 14 feet to 17 feet bgs in boring B-3. Stiff, pale olive Sandy SILT was
observed between approximately 33 feet and 35 feet bgs, as well as at 46 feet bgs
in boring B-3.
3.2 LABORATORY ANALYSES
The near surface soil is composed of non -expansive silty sand and thus an
Expansion Index (EI) was not performed.
Six sieve wash analyses were performed to further classify the soil observed in our
subsurface exploration. The results of these analyses confirmed our field
classifications and are presented in Table 2.
Boring
B-2
.Content
2.5' - 4'
00 Sieve
13.2
M
1.3
B-3
2.5' - 4'
16.7
3.3
B-2
10' - 11.5'
20.2
2.4
B-1
15' - 16.5'
2.9
3.0
B-1
20' - 21.5'
5.6
2.7
B-3
35' - 36.5'
21.4
6.2
Table 2 — Sieve Wash Analyses
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
Six moisture -density analyses were performed on 2.5-inch diameter stainless steel
tube samples obtained during the subsurface exploration. The results of these
analyses are shown in Table 3.
Boring
B-1
Depth
3' - 3.5'
3.3
Dry Soil Density
106.8
B-1
3.5' - 4'
3.7
103.2
B-1
7' - 7.5'
1.2
104.9
B-2
7.5' - 8'
1.2
98.9
B-2
11' - 11.5'
3.7
99.2
B-2
15.5' - 16'
7.8
93.6
Table 3 — Moisture -Density Tests on Tube Samples
3.3 EXISTING FILL
Significant landfilling was not observed during the subsurface exploration for the
site.
3.4 EXISTING ASPHALT CONCRETE PAVEMENT
The existing parking area pavement sections in all three borings measured 3
inches of asphalt concrete over 5 inches of Class II aggregate base.
3.5 EXISTING FOOTING DIMENSIONS
Review of the provided structural drawings (Sheets S1, SD1 and SD2) for the
existing structure, prepared by Robert H. Ricciardi A.I.A. & Associates and
Anderson Structural Engineering, dated January 22, 2003, indicates the existing
two-story, wood -framed building is supported on a concrete slab foundation with
both pad footings and continuous footings. The plans detail a 4-inch thick concrete
slab with No. 3 reinforcing bars placed at 18-inches on center each way, over 2-
inches of sand and 10-Mil Visqueen plastic sheeting. Pad footings range in width
between 3 feet square to 6.5 feet square and have a thickness of either 12-inches
or 16-inches. Continuous footings are noted to be either 15-inches wide or 24-
inches wide; both having a thickness of 24-inches. Grade beams are noted at the
exposed columns of the store front on the eastern side of the structure, as well as,
along a portion of the western perimeter footing. The grade beams are 18-inches
wide and either 16-inches or 18-inches thick.
The design soil bearing capacity in the General Notes section on Sheet SD1 is
1,800 pcf. Minimum depth to the bottom of the footing is noted on Sheet SD1 as
being measured either from adjacent grade or top of slab.
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8. 2021
3.6 EXCAVATION EFFORT
Based upon the findings in exploratory borings, conventional grading equipment
should be able to excavate the on -site soil with reasonable expectations.
3.7 SUITABILITY FOR CONSTRUCTION
From an earthwork, pavement, and foundations viewpoint, the soil at this site is
considered suitable for support of the anticipated loads provided our
recommendations are followed properly.
10
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
4 EARTHWORK RECOMMENDATIONS
4.1 NATIVE AND IMPORT FILL MATERIAL
On -site soil (less debris and organic materials) is considered suitable as fill
material. Imported fill materials should have a plasticity index less than 15 and a
maximum particle size of 2-inches. Allow Gularte & Associates 1 week notice to
sample and test proposed import fill materials prior to delivery at the site.
E, WM a IX Weis]►Vi 17_[O 11Is] ki I
Although we do not anticipate significant grading, we provide the following
recommendations for fill compaction to be applied as needed during site
development.
Scarify the native soil to prepare for structural fill. Scarification should include
ripping the upper 8 to 12 inches of the site and moisture conditioning the soil to
within 0 to +4 percent of optimum moisture content prior to re -compaction. Any cut
portions of the building pad require scarification and re -compaction as well.
Compaction should be done with dedicated compaction equipment. Once
compaction testing has been performed on the original grade, structural fill
placement may commence.
The fill material should be moisture conditioned to within 0 to +4 percent of
optimum moisture content, spread in loose lifts not exceeding 12-inches thick, and
compacted to a minimum of 90 percent relative compaction per ASTM D1557.
Compaction should be done with dedicated compaction equipment.
We recommend that Gularte & Associates be retained to check that existing soil
has been prepared properly, and to test structural fill placement every 12 to 18
inches to verify that the soil has been compacted adequately during the grading
operations.
4.3 TRENCH BACKFILL
The contractor is responsible for conducting all trenching and shoring in
accordance with CALOSHA requirements. Place and compact trench backfill as
follows..
Trench backfill should have a maximum particle size of 2-inches.
Moisture condition trench backfill to within 0 to +4 percent of optimum water
content; moisture condition backfill outside the trench.
Place fill in loose lifts not exceeding 12-inches for backhoes and 18-inches
for large excavators.
Compact fill to 90 percent relative compaction per ASTM D1557.
Jetting of trench backfill is not acceptable except in joint utility trenches
where damage to conduits makes mechanical compaction methods
impractical.
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number. 4969 December 8, 2021
4.4 SITE DRAINAGE
Surface drainage design should include the following:
1. Slope concrete pavement areas at least '/2 percent and asphalt concrete
pavements at least '/2 and preferably 1 percent to extend pavement life. Do not
allow water to pond on pavement areas.
2. If soil surrounds the building, discharge roof down spouts to storm drain
system. Where soil surrounds the building, provide a 5 percent slope away
from building exteriors for a distance of at least 3 feet.
3. Direct sprinklers away from buildings. Use drip irrigation near the structure and
pavements. Excess watering increases to risk of premature pavement failure
and shrink/swell underneath the structure.
12
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
5 FOUNDATION RECOMMENDATIONS
5.1 FOUNDATIONS
If building renovations require additional footings, we recommend that they bear in
competent native soil or compacted fill per our recommendations in Section 4.
Continuous footings should be at least 12-inches wide and at least 18-inches deep
below adjacent pad grade. Spread footings should be at least 36-inches wide and
18-inches deep below adjacent pad grade.
Table 4 below provides maximum allowable bearing capacity for dead plus live
loads for the primary structure (inclusive of wind and seismic loads).
FootingMinimum .. - Bearing Capacity
Strip Footings 12" Wide x 18" Deep 2,100
Spread Footings 36" Wide x 18" Deep 2,800
Spread Footings 60" Wide x 18" Deep 3,600
Table 4 — Footing Parameters
For perimeter strip footings, provide at least two No. 4 reinforcing bars top and two
No. 4 bars bottom.
Lateral loads may be resisted by friction along the base of footings and by passive
pressure along the face of footings. The passive pressure is based on an
equivalent fluid pressure in pounds per cubic foot (pcf). We recommend a passive
lateral pressure of 346 pcf and a coefficient of friction equal to 0.34 for design.
Utility excavations parallel to footing lines should be clear of a 1:1
(horizontal -vertical) plane projected downward from the base of footings. Where
utility lines cross footings, they should be sleeved and footings deepened as
appropriate.
5.2 SLAB ON GRADE
We recommend the following for slabs -on -grade:
1. 1-inch of clean 3/8-inch pea gravel underlain with,
2. Vapor barrier membrane consisting of 10-mil polyethylene "plastic" sheeting,
properly sealed at penetrations and edges, underlain with
3. Four inches of clean crushed rock on the building pad. Crushed rock should
have 100 percent passing the %-inch sieve and less than 5 percent passing the
No. 4 Sieve.
4. Provide a minimum concrete thickness of 5 inches or as determined by the
structural engineer.
13
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN: 600-390-023)
Job Number.- 4969 December 8, 2021
5. Reinforce slabs with No. 4 reinforcing bars placed on 24-inch centers each
way. Place dobies per ACI; we recommend a maximum dobie spacing of 6-feet
on center, each way.
6. Use a concrete water -cement ratio of 0.50 or less.
7. Use higher strength concrete, minimum 3,000 psi.
Slab thickness and reinforcing steel requirements above are provided for purposes
of resisting soil expansion potential. The structural engineer may increase these
parameters based on building loads or anticipated building use. The structural
engineer should provide final design thickness and additional reinforcement, if
necessary, for the intended structural loads.
Exterior Flatwork: Exterior flatwork includes items such as concrete sidewalks,
steps, and outdoor courtyards exposed to foot traffic only. Provide a minimum
concrete flatwork thickness of 4-inches over 4 inches of Class II aggregate base
rock.
5.3 RETAINING WALL PARAMETERS
Provided that adequate drainage is included, we recommend that walls subjected
to active soil pressure be designed to resist an equivalent fluid pressure of 45
pounds per cubic foot (pcf). For at -rest conditions, we recommend an at -rest fluid
pressure of 66 pcf with level backfill conditions. Retaining wall backfill should be
predominantly granular, non -expansive backfill. Generally, we expect horizontal
movements for retaining walls under active pressure conditions to rotate laterally
an amount equal to 1 percent of the height of the wall.
The above lateral earth pressures assume sufficient drainage behind the walls to
prevent any build-up of hydrostatic pressures (i.e. sump) from surface water
infiltration and/or a rise in the ground water level. Drainage of the walls may be
accomplished by one of the following methods:
1. Clean drain rock wrapped in Mirafi 140N non -woven filter fabric or
equivalent as approved by our office. Drain rock should be % to 1-1/2 inch
in size and should have less than 5 percent passing the No. 200 sieve.
Rock can be crushed or rounded. Drain rock should be 12 inches wide and
extend to within 12 inches of subgrade.
2. Caltrans Class II Permeable material placed 12 inches wide and extended
to within 12 inches of subgrade. The Caltrans Class II Permeable is self
filtering; and as such a geotextile filter fabric is not necessary.
3. Geocomposite drainage can be used in lieu of crushed rock. We commonly
recommend Amerdrain C96 geocomposite drainage board. The product
should be installed per the manufacturer's directions. We recommend the
wider drainage board be placed in the lower 2 feet of the wall. It is important
that the proper transition pieces are used to transition from the
geocomposite to 4-inch tight pipe for outletting purposes.
14
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN: 600-390-023)
Job Number: 4969 December 8, 2021
In either of the above cases, we recommend waterproofing of the walls with a
product such as Sonneborne 5000 or equivalent as reviewed and approved by our
office in writing. Waterproofing should be applied per the manufacturer's
instructions.
Water collected at the bottom of the drain system should be transmitted away from
the wall by a perforated pipe or weep holes. The pipe should be at least four
inches in diameter with the perforations placed down (lettering typically on top).
The pipe should daylight to a lower grade or connect to a sump, storm drain, or
other suitable disposal facility. If adequate drainage is not provided, we
recommend that an additional equivalent fluid pressure of 40 pcf be added to the
values recommended above.
5.4 2019 CBC SEISMIC PARAMETERS
We provide the 2019 California Building Code parameters in the table below.
CategorizationDesign
Site Latitude
33.708614 N
Site Longitude
116.278025 W
Site Class
D
Risk Category
II
MCER Ground Motion 0.2 second period (Ss)
1.655
MCER Ground Motion 1.0 second period (Si)
0.676
Site Amplification Factor at 0.2 second (Fa)
1.0
Site Amplification Factor at 1.0 second (Fv)
1.7
Site Modified Spectral Acceleration (SMs)
1.655
Site Modified Spectral Acceleration (Smi)
1.149
Numeric Seismic Design Value (SDs)
1.103
Numeric Seismic Design Value (SD1)
0.766
Seismic Design Category
D
Table 5 — 2019 CBC Seismic Parameters
15
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8. 2021
5.5 PAVEMENT DESIGN
5.5.1 Asphalt Concrete Pavement for Automobile Parking Areas
Several different asphalt pavement sections are shown in the table below. Our
design is based on an R-value of 15 and Procedure 608 of the Caltrans Highway
Design Manual. Contact our office for an alternative pavement design, if so
desired.
A possible option to reduce the aggregate baserock within the parking area is to
lime treat the asphalt pavement subgrade. Typically, this option may result in a 1/3
reduction in baserock thickness. Should this option be of interest, contact our
office for further analysis and recommendations.
5.5.2 Trash Enclosure Concrete Pavement Design
Use concrete pavement sections to resist heavy loads and turning forces in areas
such as trash enclosures. We recommend the following minimum design sections
for rigid pavements:
Place 6 inches of concrete over 6 inches of aggregate base compacted to
at least 95 percent relative density per ASTM D1557.
y Concrete pavement should have a minimum 28-day compressive strength
of 3,000 psi.
Provide minimum control joint spacing in accordance with Portland Cement
Association guidelines.
Reinforce slabs with No. 4 reinforcing bars placed on 24-inch centers, each
way, placed within the middle third of the slab. Place dobies per ACI. If
shrinkage cracking is acceptable and the concrete is not subject to heavy
truck traffic, then reinforcing bar could be replaced with the appropriate type
and amount of fiber mesh.
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GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
5.5.3 Special Inspections
We recommend the following minimum special inspections as part of any
proposed grading and/or foundation additions. The project architect, governing
agency, or structural engineer may require other inspections.
➢ Observation that the previous structure footings have been removed and
the resulting excavations backfilled and compacted to a minimum of 90
percent relative compaction, per ASTM D1557.
➢ Compaction testing during grading.
➢ Observation of proposed footing excavations.
➢ Observation of slab reinforcing steel.
➢ Observation, sampling, and testing of concrete during the slab pour only.
17
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8. 2021
6 LIMITATIONS
The scope of this evaluation was limited to an evaluation of the load -carrying
capabilities and stability of the subsoils. Oil, hazardous waste, radioactivity,
irritants, pollutants, molds, or other dangerous substance and conditions were not
the subject of this study. Their presence and/or absence is not implied or
suggested by this report and should not be inferred.
The accompanying report summarizes the findings and opinions of Gularte &
Associates, Inc. Our findings and opinions are based on information obtained on
given dates by borings, laboratory testing, engineering judgment, and analyses.
The analyses, conclusions, and recommendations contained in our report are
based on site conditions as they existed at the time of our study, and further
assume that probes such as exploratory borings are representative of the
subsurface conditions throughout the site; i.e., the subsurface conditions
everywhere are not significantly different from those disclosed by the probes.
If during construction different subsurface conditions from those encountered
during our exploration or different from those assumed in design are observed or
appear to be present, or where variations from our design recommendations are
made, we must be advised promptly so that we can review these conditions and
modify the applicable recommendations if necessary. We cannot be held
responsible for differing site conditions, changes in design, or modified
geotechnical recommendations not brought to our attention.
Soil conditions cannot be fully determined by borings and, therefore, unanticipated
soil conditions are commonly encountered. Such unexpected soil conditions often
require that additional expenditures be made to attain a properly constructed
project. Therefore, some contingency funding is recommended to accommodate
potential extra costs.
Foundation dimensions, minimum slab thickness, and reinforcing details
recommended herein are based upon geotechnical and construction
considerations and are not offered in lieu of foundation design by an engineer. A
determination of flooding potential, the existence of wetlands, or corrosive soil was
beyond the scope of this report.
This geotechnical study did not include an investigation regarding the existence,
location, or type of possible hazardous materials. If an investigation is necessary,
we should be advised. In addition, if any hazardous materials are encountered
during construction of the project, the proper regulatory officials should be notified
immediately.
This report was prepared for the specific use of our client and applies only to the
subject property. We are not responsible for interpretations by others of data
presented in this report. This report is not a legal opinion. No warranty is
expressed or implied. We base our conclusions in this report on judgment and
experience. We performed this work in accordance with generally accepted
standards of practice existing in northern California at the time of the report.
18
GEOTECHNICAL REPORT
46805 Dune Palms Road — La Quinta, California (APN. 600-390-023)
Job Number: 4969 December 8, 2021
Gularte & Associates, Inc. is not an expert on mold prevention. If particular
recommendations are desired to prevent mold, we recommend that you contact an
expert in that field.
19
FIGURES
Figure 1 — Vicinity Map
Figure 2 — Site Plan
Figure 3 — Geologic Map
Figure 4 — USGS Unified Hazard Curves
Figure 5 — CGS Seismic Hazards Map
- -T
r-
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'�
•ylr1G��•ii -
'. . All
I'M., K-
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1 1!
:' .+ � J • is „ F
A
N Source: Google Earth
Vicinity Map u lame
& ASSOCIATES INC
Geotechnical Consoltants
46805 Dune Palms Rd. - La Quinta
(APN: 600-390-023) P.O. Box490 ♦ Lincoln, CA 95648
916.771.5051 FAX 916.771.5868
December 2021 1 Job No. 4969 Figure 1
!7
•'1
eTI=
�
1 ,
Ir
Of
Legend:
Boring Location
N Source: Google Maps
Site Map u lame
& ASSOCIATES INC
Gootachnical Consultants
46805 Dune Palms Rd. - La Quinta
(APN: 600-390-023)
December 2021 1 Job No. 4969 Figure 2
r'I 11 Wetei
Indian Wells`�\� {`
ram_
PALM DESERT AND COACHELLA MAP (DF-373)
LEGEND
L°!--joa08 ac Of
SURFICIAL SEDDdENTS d
Unindurated, undissectedallavialsediments
Og Alluvial sand and gravel of Whitewater River a
Oa Alluvial sand and day of valley areas
Oa Wind -laid dune sand O
Oc Clay of playa lakes, light gray, generally alkaline, with some micaceous silt
Of Alluvial fan gravel
UNC0NF0RM!TY
9ro Fq-
qdNd Mqd
PLUTONIC ROCKS
C—itic vend dio.itic rock, of P—i—L., Range, iatr-de into Palcoloie or older
metamorphic rocks; age, Mesozoic
grd Gray biotite-Ach granodionte to quartz diorite
qm Quartz monzonae
gdVgd Quartz dlortfe, light gray, massive to gnelssoid, contains some xenoliths locally,
abundant biotite, coherent
qdl-gdgd-gn Same as qdI and qd but more gneissoid, ;ncludes some gneiss migmatite
mqd Same as qd but sheared (at depth) to mylontle, foliated
di Dionte gabbro
mS
mt;-gn
A METASEDIMENTARY ROCKS
Metasedimrntary complex, deformed sedimentary rocks; age, Mesozoic or older
mama-gn (includes metasedlments o1 Palm Canyon Complex of Miller 1946) Mica schist to
phyllife and gneiss, dark gray, foliated, locally includes homlels, tactile
N mI Marble, limmlone to dolomite, white to light blue -gray, fine to medium, crystalline,
bedded J
Adapted from the Geologic Map of the Palm Desert & Coachella 15-Minute Quadrangles, Riverside County, Californi,
Geologic Map
46805 Dune Palms Rd. - La Quinta
(APN: 600-390-023)
fA
N
0
fn
T.W.. Jr.. and Minch. JA., 2008.
u larte
& ASSOCIATES INC.
Geotechnical Consultants
December 2021 1 Job No. 4969 1 Figure 3 1
Unified Hazard Tool
Please do not use this tool to obtain ground motion parameter values for the design code reference documents covered by the U.S. Seismic Design Maps web tools le.g., the International Building Code and the ASCE 7 or 41
Standard). The values returned by the two applications are not identical.
- Earthquake Hazard and Probability Maps
^ Input
Edition
Spectral Period
Dynamic: Conterminous U.S. 2014 (update) (v4.2.0)
Peak Ground Acceleration
Latitude
Time Horizon
Decimal degrees
Return period in years
33.708614
2475
Longitude
Decimal degrees negative values for western longitudes
xr -, 5%i 550years
-116.278025
Choose location using a map
Site Class
259 m/s (Site class D)
^ Hazard Curve
Hazard Curves
Uniform Hazard Response Spectrum
le*o
3.0
led
to
V �a
w le-2
�
2.5
w
le-3
p0
o le-4
0 2.0
u Time Horizon 2475 years
le-5 -♦ Peak Ground Acceleration
v 1.5
7 ---�- 0.105econd Spectral Acceleration
c
yle-6- 0.205econd Spectral Acceleration
LL—0.305econd Spectral Acceleration \l
p
n le-7 + 0.50 Second Spectral Acceleration
1.0
— 0.75 Second Spectral Acceleration
a le-8 t 1.00 Second Spectral Acceleration
5 Spectral Period (s): PGA
2.00Second5pec1ralAcceleration
Ground Motion (g):0.6662
le-9 3.00 Second Spectral Acceleration
403 Second Spectral Acceleration
1e-10 -+ 5.00 Second Spectral Acceleration
3
1e-2 1e-1 le+0
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
Ground Motion (g)
Spectral Period (s)
Source: United States Geological Survey (USGS) Unified Hazard Tool (https://earthquake.usgs.gov/hazards/interactive/)
USGS Seismic Hazard Curves
u lame
& ASSOCIATES INC.
Geotechnical Consultants
46805 Dune Palms Rd. -
La Quinta
(APN: 600-390-023)
December 2021
1
Job No. 4969
Fi ure 4
JA
79W
79430
194 46805
90441 *7%.
79640 79660
46465 967
46491
46515 79675
3 9661
46541
Address: 46805 DUNE PALMS RD
600390023
City
LA QUINTA
Address
46805 DUNE PALMS RD
FauhZone
This parcel is NOT WITHIN an
Earthquake FauRZone.
Liquefaction
This parcel has NOT been
Zone
EVALUATED by CGS for
I quefact on hazards.
Landsl de
This parcel has NOT been
Zone
EVALUATED by CGS for
se sm c landslide hazards.
Zoom to
•••
79513
47'2D
r
47350
the CGS Rezula
CGS Seismic Hazards Map
46805 Dune Palms Rd. - La Quinta
(APN: 600-390-023)
December 2021 1 Job No. 4969
79740
79710 1 79724
79840
�r
79075
79705 1 ;79775
7970579705
79785
laps Geo Application.
u lame
& ASSOCIATES INC.
Geotechnical Consultants
APPENDIX A
Boring Logs
Auger Hollow Stem Auger I� Project No. 4969
Size 6-inch Project Name 46805 Dune Palms Rd
Vx
Drill Mobil B-61 Elevation -60-ft MSL
Logged By J. Zlotkowski L '; Date November 19, 2021
r
Boring # B-1
0
0)
SPT or Cal Mod "N" Value
m
U j
o
o
(Uncorrected)
z
E
LITHOLOGIC DESCRIPTION
o
J
o
V
V
Asphalt: 3" AC / 5" AB
.TTTTT
.T. T .T. T .T.•
Silty Sand: (SM) light brownish olive,
TTTTT'
'.T.' '.T.' '.T.•
damp, fine grain, poorly graded,
1.1
8/12/13
CAL
TTTTT
.T. T .T. T .T.•
medium dense.
.TTTTT .
.TTTTT .
TTTTT .
5
— — — �'
Sand with Silt: (SP-SM) light brown,
0 20
40
60
80
100
5
1.2
2/3/5
SPT
-- -- --
damp, fine grain, loose.
Sand: (SP) light brown, dry/damp, fine
0 20
40
60
80
100
10
grain, medium dense.
10
1.3
7/10/11
CAL
121
0
40
60
�80
100
15
15
1.4
7/7/9
SPT
— — —
Sand with Silt: (SP-SM) light brown,
-- -- --
damp, fine grain, medium dense.
0 20
40
60
80
100
20
1.5
7/7/12
SPT
_ _ _
No Groundwater.
20
0 20
40
60
�80
100
25
25
30
30
Client Project Sheet
Market Street Development, LLC. 46805 Dune Palms Rd - La Quinta 1 of 1
Auger Hollow Stem Auger I� Project No. 4969
Size 6-inch Project Name 46805 Dune Palms Rd
Vx
Drill Mobil B-61 Elevation —60-ft MSL
Logged By J. Zlotkowski L '; Date November 19, 2021
r
Boring # B-2
0
0)
SPT or Cal Mod "N" Value
m
U j
o
o
(Uncorrected)
z
E
LITHOLOGIC DESCRIPTION
o
J
o
V
V
Asphalt: 3" AC / 5" AB
.TTTTT'
Silty Sand: (SM) light brownish olive,
TTTTT'
•.T.' •.T.'
damp, fine grain, poorly graded,
2.1
12/13/21
SPT
.T. T.T. T.T.'
T T T T T
dense.
.TTTTT .
.TTTTT .
TTTTT
0 20
40
60
80
100
5
2.2
4/6/6
SPT
.TTTTT'
Medium Dense at 5-ft bgs.
5
,T, T ,T, T ,T,'
.TTTTT .
LET. z'
------------.
2.3
7/12/14
CAL
-- -- --
Sand with Silt: (SP-SM) light brown,
— — —
damp, fine grain, medium dense.
TTTTT'
Silty Sand: (SM) light brownish, damp,
0 20
40
60
80
100
10
2.4
6/7/7
SPT
TTTTT
TTTTT
fine grain, medium dense.
10
.TTTTT .
.TTTTT .
.TTTTT .
.TTTTT .
.TTTTT .
.TTTTT .
T .
TTT .
T
-T,f-T-.t-T,
----------------
Sand: (SP) light gray, dry/damp, fine
0 20
40
60
80
100
15
grain, medium dense.
15
2 5
14/15/18
CAL
Silt: with sand (ML) light brown, moist,
.TTTTT .
very stiff.
Silty Sand: (SM) light gray, damp, fine
,TTTTT ,
TTTTT
:TTTTT'
TTTTT•
, rainpoorly raded, medium dense.
g p Y g
T.TTT
-- -- --
Sand with Silt: (SP-SM) light olive,
�80�
20
— — —
damp, fine grain, medium dense. Thin
0 20
40
60
100
20
2.6
4/8/13
SPT
-- -- --
pale olive sandy silt layers.
No Groundwater.
0 20
40
60
80
100
25
25
30
30
Client Project Sheet
Market Street Development, LLC. 46805 Dune Palms Rd - La Quinta 1 of 1
Auger Hollow Stem Auger I� Project No. 4969
Size 6-inch Project Name 46805 Dune Palms Rd
Mobil B-61 Elevation —60-ft MSL
Drill <t ,. ; �:3 .
Logged By J. Zlotkowski L Date November 19, 2021
Boring # B-3
0
0
0-
0)
SPT or Cal Mod "N" Value
m
U j
o
o
(Uncorrected)
z
E
LITHOLOGIC DESCRIPTION
o
J
o
JV
3.7
4/6/6
SPT
JV
:TTTTT:
Silty Sand: (SM) pale olive, moist, fine
•TTTTT •
grain, poorly graded, medium dense.
.TTTTT .
.TTTTT .
.TTTTT .
TTTTT .
------------------------------
Sandy Silt: (ML) pale olive, moist, stiff.
0 20
40
60
80
100
35
35
3.8
5/7/10
SPT
TT,T, T,T,
M. T T T T •
Silty Sand: (SM) olive, moist, fine
T• 'T .1..
',T, T ,T,'
rain, poorly graded, medium dense.
g p Y
.TTTTT .
TTTTT .
T T T T T.
.TTTTT .
Sand with Silt: (SP-SM) pale olive,
0 20
40
60
�80
100
40--3.9
— — —
damp, fine grain, poorly graded,
40
5/8/13
SPT
medium dense.
45
__ __ __
0 20
40
60
80
100
45
3.10
5/5/5
SPT
--------------
Sandy Silt: (ML) olive, very moist, stiff.
Sand with Silt: (SP-SM) light gray,
— — —
-- -- --
damp, fine grain, poorly graded,
— — —
medium dense.
0 20
40
60
80
100
50
— — —
50
3.11
8/10/11
SPT
No Groundwater
0 20
40
60
80
100
55
55
60
60
Client Project Sheet
Market Street Development, LLC. 46805 Dune Palms Rd - La Quinta 2 of 2
APPENDIX B
Laboratory Test Results
ASTM D1140 Sieve Wash Over The No. 200 Screen
Project No.: 4969
Project Name: 46805 Dune Palms Rd - La Quinta
Date: 12/2/21
Soil Description: See Logs
Basic Information
Procedure Used (A or B) A
Preparation Method Used (Wet or Dry) Wet
Boring #
Depth
Pan #
Mass of Container
Mass of Dry Specimen+Container
Mass of Dry Washed+Container
Percent Passing No. 200 Sieve
Mass of Container+Wet Specimen
Mass of Container+Dry Specimen
Water Content %
u larte
B-2
B-3
B-2
I B-1
I B-1
I B-3
2.5'-4'
2.5'-4'
10'-11.5'
1 15-16.5'
1 20'-21.5'
35-36.5'
25
68
42
63
5
81
197.4
193.6
185.8
190.4
191.0
184.4
392.4
411.2
410.4
415.2
440.0
425.0
366.6
374.8
365.0
408.6
426.0
373.4
13.2
16.7
20.2
2.9
5.6
21.4
395.0
418.4
415.8
422.0
446.6
439.8
392.4
411.2
410.4
415.2
440.0
425.0
1.3
3.3
2.4
3.0
2.7
6.2
ASTM D2216/2922 Moisture/Density Test
Project No.: 4969
Project Name: 46805 Dune Palms Rd - La Quinta
Sampling Locations: See Site Plan
Soil Description: See Boring Logs
Boring Location
Sample Depth
Water Content Calculations
Obtain Mass of Container
n Mass of Wet Specimen+Container
in Mass of Dry Specimen+Container
Water Content (%)
Soil Density Calculations
Obtain Mass of Mold:
Obtain Mass of Soil and Mold:
Total Mass of Soil
Length of sample
Wet Soil Density
Dry Soil Density
Notes
quiarte
B-1
B-1
B-2
B-2
B-1
I B-2
3'-3.5'
3.5'-4'
7'-7.5'
7.5'-8'
11'-11.5'
1 15.5'-16'
No.1
No.2
No.4
No.5
No.3
No.6
193.8
190.4
186.0
191.0
198.8
184.4
631.8
797.0
627.2
807.4
828.2
831.6
617.8
775.4
621.8
799.8
805.8
784.6
3.3
1 3.7
1 1.2
1 1.2
1 3.7
1 7.8
No.1 No.2 No.4 No.5 No.3 No.6
280.4
279.8
275.8
254.0
252.8
273.2
1081.0
1056.0
1046.0
950.2
999.2
920.4
800.6
776.2
770.2
696.2
746.4
647.2
6.0
6.0
6.0
5.8
6.0
5.3
110.3
107.0
106.1
100.1
102.9
101.0
106.8
103.2
104.9
98.9
99.2
93.6
APPENDIX C
Site Photographs
IV
cY`�'+ti1lrlc?`wvw!s�'��.a,�`ri;�:s..'AzW"�„2.ir,�.ui�"_�'Y,rx:F,,,�`�4L'���jb:�':S.S."atRSla�h�1L»,i,�Y,.2Sw.tad..•iak•.�S"`_:�$�.'��::iih;�u!�e-5ti;de;c,i..,..&`..''��"e�.c_.i,,'`av, r-.. .`-i::� _._,. ..., ., ..�v:.�''A\„�.,..j.:... -._ ,. .
Looking southwest along northern face of existing structure.
Looking south along eastern face of existing structure.
t
_ _LP
�_ k
� ■
_ ■_'
�.
�_ ��� -_`
� � _
j�
48-805
Looking northeast at the western face of existing structure.
APPENDIX D
Geotechnical Terms/Definitions
Referenced Geotechnical Terms
ASTM: American Society for Testing and Materials is one of the largest voluntary standards
development systems in the world. Soils and materials tests are described in detail in their
annual books of standards.
Bench: A relatively level step, excavated into acceptable material of a slope face, against which
fill is to be placed. Its purpose is to provide a firm and stable contact between the existing
material and the new fill to be placed.
Buttress: An engineered fill designed and built to support or retain a weak or unstable Slope.
Compaction: The densification of soil through mechanical manipulation (tamping, rolling,
vibrating, etc.). The addition of optimum amounts of water can be crucial to obtaining adequate
densification of the material.
Cut: The depth to which a material is to be removed/excavated to reach final grade elevation.
Consolidation: The gradual reduction in volume of a soil mass due to an increase in
compressive stress (load).
Daylight Line: The surface contact of cut and fill soil.
Density Test: A field test used to determine compaction of a fill or native soil. The test is
typically performed by the nuclear gauge method.
Expansive Soil: A soil (usually clayey) that increases in volume when water is added (expands),
and shrinks when water content is reduced.
Geotechnical: Pertaining to the practical applications of soil science and civil
Engineering.
Geotextile Fabric: A permeable fabric used during grading to stabilize, allow for drainage,
filtration, or add reinforcement beneath a pavement or structure.
Maximum Density Test: ("curve", "max"," or "proctor") A laboratory test used to determine
the optimum moisture and maximum dry density of a soil type (typically ASTM standard test
method D 1557).
Native Soil (Natural Ground, NG): (1) Soil deposited by the forces of nature through
weathering, erosion, etc.; soil that has not been moved by man. (2) The undisturbed surface prior
to the commencement of grading, sometimes referred to as Original Ground (OG).
Nesting: Oversized material (typically >6" size) that has been placed in a manner that leaves
voids between the piled boulder or rock fragments, and these voids are not infilled with solid
material (soil, fine gravel/sand, etc). The absence of nesting rock is required in a rock fill.
NICET: National Institute for Certification in Engineering Technologies. Engineering technicians
that are tested by NICET may be certified at various levels of expertise (Levels I through IV) in
different fields of construction.
Optimum Moisture: The moisture content at which the maximum density of a soil can be
achieved during the compaction process. Each soil type (or blend of soil types) has its own
specific optimum moisture content that is used as a guide for moisture conditioning during the
grading process.
Over -excavation: The removal of the upper portion of soil on site. Usually performed under
roadways or building pads and combined with replacement of structural fill
Pass: One trip or movement across a designated area by a piece of compaction equipment or
machinery.
Percent Compaction: The ratio (expressed as a percentage) of the dry density of a soil (as
determined by the nuclear gauge) to the maximum density of a soil (as determined by the
maximum density test).
Pre -Saturation: The moisture conditioning (above optimum) of a pad subgrade or footing
excavation prior to placing/pouring a foundation. Pre -saturation is usually performed on
expansive soils to help limit future swelling that may be caused by seasonal rains or heavy
landscape watering.
Pumping: May be observed as a rolling motion in soils compacted in an over -optimum condition
(too wet). These pumping soils may, during the rolling process, become rutted or indented by
rubber -tired equipment, usually leaving a bulging path in the soil parallel to the tire print.
Relative Compaction: A means of comparing the dry soil density in the field to the laboratory
compaction curve. It equals the field dry density divided by the lab max dry density, and then is
multiplied by 100 and expressed as a percentage.
Rock Fill: "Oversized material' (typically 6" or larger diameter) mixed/compacted during
placement with a soil matrix in such a manner as to limit voids and nesting, allowing for a
homogeneous, well -compacted fill.
Scarify (Rip): The act of loosening the exposed surface material (usually the upper 8-12 inches
by ripper teeth on a dozer or blade) to mix, blend, moisten, or prepare for fill placement.
Structural Fill: Fill that is supporting manmade structures, including buildings, roadways, levees,
and slopes. Structural Fill is typically compacted to 90 percent relative compaction.
Subdrain: A drainage system placed beneath the surface to drain surface water, or relieve
hydrostatic pressure (such as water buildup behind a fill slope). It typically consists of filter
material (rock and/or fabric) and a perforated drainpipe.
Toe: The contact point of the bottom of a fill or cut slope with a relatively level or pre-existing
ground surface.
Transition Lot: A lot which a portion is to be cut (excavated) and a portion is to be filled (raised)
to reach pad grade.
Unified Soil Classification System (USCS): A system used by soil engineers to classify soil for
engineering purposes. A kind of a shorthand for describing soil types.