1820 Ocean Grove Dr. RES21-0003 narrative.lotdrainagedesign.2.3.21 (6 of 7)_12670 ROSSELLE STREET, Suite 8 Jacksonville FL 32204 Ph: 904-551-4945
Civil Design and Construction Management Professionals
February 2, 2021
Atlantic Beach Site Drainage Improvements
In-Fill Lots
Lot Address: 1820 Ocean Grove Drive
Atlantic Beach, FL
NARRATIVE:
The attached calculations are provided to support the lot drainage design at 1820 Ocean
Grove Drive in the City of Atlantic Beach, FL. The calculations were performed utilizing the
equations in the city ordinance sec 24-66(b).
The referenced project site was vacant and the calculations utilized this as the predevelopment
condition. The total lot area shown in the pre and post calculations was calculated from the
table in the survey.
The proposed project will construct a home, driveway, and stormwater storage facility.
The runoff coefficient was provided based on the impervious values and associated
coefficients of sec 24-66(b) of the code.
______________________________
Reynold D. Peterson, Sr Project Manager
FL P.E. # 84559
Comp. By:
Date:
Public Works Department
City of Atlantic Beach
Permit No:RES21-003
Address:1820 Ocean Grove Drive
Required Storage Volume
Criteria:
Section 24-66 of the City of Atlantic Beach's Zoning, Subdivsion, and Land Development Regulations requires
that stormwater runoff from impervious areas be stored onsite. Volume to be retained is as follows:
V = CAR/12 which is the Modified Rational Method for estimating stormwater runoff
Where: V = Volume of Runoff to be stored (cubic feet)
C = Runoff Coefficient, 0.92, the difference between impervious area (C=1.0)
and undeveloped conditions (C=0.08).
A = Impervious Area (square feet)
R= 25-yr / 24-hr rainfall depth (9.3 inches for Atlantic Beach)
Onsite Storage Volume Required for Impervious Area:
Lot Area = 7,500 ft2
Impervious Area (A) = 3,312 ft2 =44.2%
V = 0.92 x 3,312.0 x9.3/ 12
V = 2,361 ft3
Provided Storage:
Area 1 - FRONT Area Storage Sideslope:4 :1
(ft)(ft2) (ft
3)
10.0 69 BOTTOM size:X
11.0 267 TOB size:X
Area 2 - BACK Area Storage
(ft) (ft
2) (ft
3)
8.8 198 BOTTOM size:X
11.0 769 TOB size:X
Area 3 - Relative Elev. Area Storage
(ft) (ft
2) (ft
3)
0.0 0 BOTTOM size:0 X 0
0.0 0 TOB size:0 X 0
Inground Storage: = A*d/pf
Total Storage Area at TOB (A) =1036.0 ft2
Depth to ESHWT from BOTTOM (d) =3.0 ft, default is 2.0 ft, verify onsite ESHWT
Pore Factor (pf) = 0.4 default is 0.4
Inground Storage Provided =1243.2 ft3
Required Treatment Volume =2,361 ft3
Supplied Treatment Volume =2,475 ft3
168
1,064
0
2/2/2021
Retention 1820 Ocean Grove Dr 2/2/2021
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
REPORT OF GEOTECHNICAL EXPLORATION
1820 OCEAN GROVE DRIVE
ATLANTIC BEACH, FLORIDA
LEGACY PROJECT NO. 20-1252.1
Prepared for:
Pinnacle Homes
265 Edge of Woods Road
St. Augustine, Florida 32092
Prepared by:
Legacy Engineering, Inc.
6424 Beach Boulevard
Jacksonville, Florida 32216
Phone: 904.721.1100
www.legacyengineeringinc.com
November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
November 2, 2020
Mr. Tim Quinn
Pinnacle Homes
265 Edge of Woods Road
St. Augustine, Florida 32092
Report of Geotechnical Exploration and Engineering Services
1820 Ocean Grove Drive
Atlantic Beach, Florida
Legacy Project No. 20-1252.1
Dear Mr. Quinn:
As requested, Legacy Engineering, Inc. has completed a geotechnical exploration for the subject
project. The exploration was performed to evaluate the general subsurface conditions within the
area of the proposed house structure, and to provide guidelines to facilitate foundation support
and earthwork preparation.
We appreciate this opportunity to be of service as your geotechnical consultant on this phase of
the project. If you have any questions, or if we may be of any further service, please contact us.
Sincerely:
Legacy Engineering, Inc.
Jared Pitts, E.I. John E. Ellis II, P.E.
Geotechnical Engineer Licensed, Florida No. 45202
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
Table of Contents
1.0 PROJECT INFORMATION .............................................................................................1
1.1 SITE LOCATION AND DESCRIPTION ............................................................................................................... 1
1.2 PROJECT DESCRIPTION .................................................................................................................................. 1
2.0 FIELD EXPLORATION....................................................................................................1
3.0 LABORATORY TESTING ...............................................................................................1
4.0 GENERAL SUBSURFACE CONDITIONS ....................................................................1
4.1 GENERAL SOIL PROFILE ................................................................................................................................ 1
4.2 GROUNDWATER LEVEL ................................................................................................................................. 2
5.0 BUILDING AREA RECOMMENDATIONS ..................................................................2
5.1 GENERAL ...................................................................................................................................................... 2
5.2 BUILDING FOUNDATIONS .............................................................................................................................. 2
5.2.1 BEARING PRESSURE...................................................................................................................................... 2
5.2.2 FOUNDATION SIZE ........................................................................................................................................ 3
5.2.3 BEARING DEPTH ........................................................................................................................................... 3
5.2.4 BEARING MATERIAL ..................................................................................................................................... 3
5.2.5 SETTLEMENT ESTIMATES ............................................................................................................................. 3
5.3 SITE PREPARATION FOR SHALLOW FOUNDATIONS ........................................................................................ 4
6.0 LIMITATIONS ...................................................................................................................5
APPENDIX A ................................................................................................................................. I
FIELD EXPLORATION PLAN ....................................................................................................................................... I
GENERALIZED SOIL PROFILES .................................................................................................................................. I
TEST BORING RECORDS ............................................................................................................................................. I
APPENDIX B ............................................................................................................................... II
KEY TO SOIL CLASSIFICATION ................................................................................................................................. II
FIELD AND LABORATORY TEST PROCEDURES ...................................................................................................... II
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
20-1252 1 November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
1.0 PROJECT INFORMATION
1.1 Site Location and Description
The site for the subject project is located at 1820 Ocean Grove Drive in Atlantic Beach,
Florida. The subject site is relatively cleared with vegetation consisting of grass and a few
scattered trees. Adjacent properties are occupied by existing residential structures. Based
on visual observations, the site is relatively level.
1.2 Project Description
Project information has been provided to us in discussions with you. Based on the
information provided to us, we understand the proposed project will consist of constructing
a single-family residential structure at the subject site. Construction of the proposed home
will likely consist of concrete-masonry-units (CMU) and/or timber framing. We have not
been provided with detailed foundation loading information; therefore, we have assumed
the wall, column, and floor slab loads will not exceed 3.0 klf, 40.0 kips, and 40 psf,
respectively. We have assumed approximately 2 feet of fill above existing grade will be
required within the area of the proposed house.
2.0 FIELD EXPLORATION
In order to explore the subsurface conditions within the area of proposed construction, 3
Standard Penetration Test (SPT) borings (B1 through B3) were conducted to depths of 20
feet each below existing grade. The borings were located by measurement from existing
site features, and should be considered accurate to the degree implied by the method
utilized. The SPT borings were conducted in accordance with ASTM D 1586. The
subsurface conditions encountered at each boring location, and the recorded groundwater
levels, are presented on the Generalized Soil Profiles and Test Boring Records in Appendix
A.
3.0 LABORATORY TESTING
Soil samples recovered during the field exploration were visually classified in accordance
with ASTM D 2488. The results of the testing are presented on the Test Boring Records
and the Generalized Soil Profiles in Appendix A.
4.0 GENERAL SUBSURFACE CONDITIONS
4.1 General Soil Profile
The boring locations and general subsurface conditions that were encountered are
graphically illustrated on the Field Exploration Plan and Generalized Soil Profiles. A
relatively detailed description of the encountered subsurface conditions is presented on the
Test Boring Records. When reviewing these records, it should be understood the soil
conditions may change significantly between the boring locations. The following
discussion summarizes the soil conditions encountered.
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
20-1252 2 November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
In general, the borings encountered very loose to firm fine sand (SP) and fine sand with silt
(SP-SM) throughout the boring exploration depths of 20 feet. Topsoil was encountered at
the boring locations within the upper 2 inches.
4.2 Groundwater Level
The groundwater level was measured at the boring locations, subsequent to
boring completion, at depths of 4.8 to 5 feet below existing grade. The depth of the
groundwater level encountered at each boring location is presented on the Generalized Soil
Profiles and the Test Boring Records. The groundwater table will fluctuate
depending on tidal fluctuations, seasonal variations, adjacent construction, surface water
runoff, etc. Based on the results of our borings, review of available published data,
and our experience, we estimate the seasonal high groundwater level at the boring to
locations to be at a depth of approximately 4 feet below existing grade.
5.0 BUILDING AREA RECOMMENDATIONS
5.1 General
The following recommendations are made based upon a review of the attached soil test
data, our understanding of the proposed construction, and experience with similar projects
and subsurface conditions. If the structural loads, construction locations, or grading
information change from those discussed previously, we request the opportunity to review
and possibly amend our recommendations with respect to those changes.
Please report to us any conditions encountered during construction that were not observed
during the performance of the borings. We will review, and provide additional evaluation
as required.
5.2 Building Foundations
Based on the results of the subsurface exploration, we consider the subsurface conditions at
the site favorable for support of the proposed structure when constructed on a properly
designed shallow foundation system. Provided the soils are prepared in accordance with
the Site Preparation Section of this report, the following parameters may be used for
foundation design.
5.2.1 Bearing Pressure
The maximum allowable net soil bearing pressure for shallow foundations should not
exceed 2,500 pounds per square foot (psf). Net bearing pressure is defined as the soil
bearing pressure at the base of the foundation in excess of the natural overburden pressure.
The foundations should be designed based upon the maximum load that could be imposed
by all loading conditions.
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
20-1252 3 November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
5.2.2 Foundation Size
The minimum widths recommended for any isolated column footing and continuous wall
footings are 24 inches and 12 inches, respectively. Even though the maximum allowable
soil bearing pressure may not be achieved, these width recommendations should control the
size of the foundations.
5.2.3 Bearing Depth
The foundations should bear at a depth of at least 12 inches below the grade existing at the
time of our exploration. We recommend stormwater and surface water be diverted away
from the building exterior, both during and after construction, to reduce the possibility of
erosion adjacent to exterior footings.
5.2.4 Bearing Material
The foundations may bear on either the compacted suitable in-place natural soils or
compacted structural fill. The bearing level soils, after compaction, should exhibit
densities of at least 95 percent of the maximum dry density as determined by ASTM D
1557 (Modified Proctor), to the depth described subsequently in the Site Preparation
section of the report. In addition to compaction, the bearing soils must exhibit stability and
be free of “pumping” conditions.
5.2.5 Settlement Estimates
Post-construction settlement of the structure will be influenced by several interrelated
factors, such as (1) subsurface stratification and strength/compressibility characteristics of
the bearing soils; (2) footing size, bearing level, applied loads, and resulting bearing
pressures beneath the foundations; (3) site preparation and earthwork construction
techniques used by the contractor, and (4) external factors, including but not limited to
vibration from offsite sources and groundwater fluctuations beyond those normally
anticipated for the naturally-occurring site and soil conditions which are present.
Our settlement estimates for the structure are based upon the use of successful adherence to
the site preparation recommendations presented later in this report. Any deviation from
these recommendations could result in an increase in the estimated post-construction
settlement of the structure.
Due to the sandy nature of the surficial soils, following the compaction operations, we
expect a significant portion of settlement to be elastic in nature. This settlement is
expected to occur relatively quickly, upon application of the loads, during and immediately
following construction. Using the recommended maximum bearing pressure, the presented
maximum structural loads, and the field test data which we have correlated to the strength
and compressibility characteristics of the subsurface soils, we estimate the total settlements
of the structure to be approximately one inch or less.
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
20-1252 4 November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
Differential settlement results from differences in applied bearing pressures and the
variations in the compressibility characteristics of the subsurface soils. Based on the
subsurface conditions as determined by the borings, it is anticipated that differential
settlements will be within tolerable limits.
5.3 Site Preparation for Shallow Foundations
We recommend the following site preparation guidelines for the proposed building area:
1.It is recommended the groundwater depth should be maintained at least two feet below the
depth of excavation required and two feet below compacted surfaces. Temporary
groundwater control measures should be implemented, as required.
2.Strip the proposed construction limits of all grass, roots, topsoil, and other deleterious
materials from within, and extending at least 5 feet beyond, the perimeter of the proposed
structure. Expect initial clearing and grubbing to average depths of approximately 6 to 9
inches.
3.Compact the exposed surface using a 5-ton roller with vibration turned off or tracked
equipment. The upper one foot of soils below the exposed surface (after stripping and
grubbing) within the building area should be improved to achieve a minimum compaction
requirement of 95% of the Modified Proctor Test (ASTM D 1557). We recommend the
compacted soils exhibit moisture contents within 2 percent of the optimum moisture
content as determined by the Modified Proctor Test (ASTM D 1557).
Should the soils experience pumping and soil strength loss during the compaction
operations, compaction work should be immediately terminated and (1) the disturbed soils
removed and backfilled with dry structural fill soils which are then compacted, or (2) the
excess moisture content within the disturbed soils allowed to dissipate before
recompacting.
4.Test the compacted surface for density at a minimum of one location per 2,500 square feet
of the proposed building area (minimum of three locations).
5.Place structural fill in loose lifts not exceeding a thickness of 8 inches if using tracked
equipment or 12 inches if using a drum roller and compact until finished subgrade is
achieved. Structural fill and backfill is typically defined as non-plastic, inorganic, granular
soil having less than 10 percent material passing the No. 200 mesh sieve and containing
less than 4 percent organic material. Typically, the material should exhibit moisture
contents within 2 percent of the Modified Proctor optimum moisture content (ASTM D
1557) during the compaction operations. Compaction should continue until densities of at
least 95 percent of the Modified Proctor maximum dry density (ASTM D 1557) have been
achieved within each foot of the compacted structural fill.
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
20-1252 5 November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
6.Perform density tests within each lift of permanent fill at a minimum of one location per
2,500 square feet of the proposed building area (minimum of three locations).
7.Excavate, compact and test footing excavations for density to a depth of one foot below
bearing level. We recommend that you test one out of every four column footings and
perform one test per every 100 linear feet of wall footing. Compaction operations in
confined areas, such as footing excavations, can best be performed with a lightweight
vibratory sled or other hand-held compaction equipment.
6.0 LIMITATIONS
We have conducted the geotechnical engineering in accordance with principles and
practices normally accepted in the geotechnical engineering profession. Our analysis and
recommendations are dependent on the information provided to us. Legacy Engineering,
Inc. is not responsible for independent conclusions or interpretations based on the
information presented in this report.
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
20-1252 i November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
APPENDIX A
FIELD EXPLORATION PLAN
GENERALIZED SOIL PROFILES
TEST BORING RECORDS
Reference
Plan Created Using Provided File
Date: 11-2-2020 Proj. No.: 20-2052 Figure 1
Approximate SPT Boring Locations
Geotechnical & Materials Engineering & Testing
Field Exploration Plan
L E G A C Y
Engineering, Inc.
1820 Ocean Grove Drive
Atlantic Beach, Florida
FIELD EXPLORATION PLAN
B1
B2
B3
B1
N =4
N =10
N =7
N =7
N =26
N =61
N =85
1 2
2 3
3 4
6 6
4 4
3 2
1 2
5 6
4 10
16
10 20
41
16 35
50
B2
N =11
N =12
N =8
N =7
N =10
N =26
N =50-5"
1 2
9 6
3 7
5 5
4 4
4 4
3 3
4 4
2 3
7
5 9
17
17 35
50-5"
B3
N =7
N =3
N =7
N =7
N =11
N =29
N =50-5"
1 3
4 3
2 2
1 3
2 3
4 4
2 3
4 8
6 4
7
4 11
18
20
50-5"
0
4
8
12
16
20
24
De
p
t
h
i
n
F
e
e
t
0
4
8
12
16
20
24
D
e
p
t
h
i
n
F
e
e
t
Strata symbols
Topsoil
Fine SAND (SP)
Fine SAND with Silt (SP-SM)
Ground Water Depth
Legacy Engineering, Inc.
GENERALIZED SOIL PROFILE
HORIZONTAL DRAWN BY/APPROVED BY DATE DRAWNSCALE:
VERTICAL 11/2/2020SCALE:1"=4'JEEII/JEEII
1820 Ocean Grove Drive
Atlantic Beach, Florida
PROJECT NO. 20-1252 FIGURE NUMBER 2
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Topsoil
Very Loose Gray Fine SAND with
Trace of Roots (SP)
Loose Light Gray Fine SAND (SP)
Loose Brown Fine SAND (SP)
Very Firm to Very Dense Grayish
Brown Fine SAND (SP)
1
2
3
4
5
6
1
2
2
3
3
4
6
6
4
4
3
2
1
2
5
6
4
10
16
10
20
41
4
10
7
7
26
61
L E G A C Y TEST BORING RECORD JOB NO.20-1252
ENGINEERING, INC.
Geotechnical & Materials Engineering and Testing BORING NO.B1
Project 1820 Ocean Grove Drive Sheet 1 of
Boring Location See Field Exploration Plan Boring Begun 10/19/20
Ground Elevation N/A Datum N/A Boring Completed 10/19/20
Groundwater Depth 5 Feet Driller DK
Length of Casing Set 5 Feet Casing Size 4 Inches Engineer J. Ellis II, P.E.
REMARKS:BORING & SAMPLING: ASTM D1586/CORE DRILLING: ASTM D2113
BLOW COUNT IS THE NUMBER OF BLOWS OF 140 LB. HAMMER
Ground Water Table FALLING 30 IN. REQUIRED TO DRIVE 1.4 IN. I.D. SAMPLER 1 FT.
ELEV.
(FT)
DEPTH
(FT)MATERIAL DESCRIPTION
SO
I
L
SY
M
B
O
L
SA
M
P
L
E
NO
.
BLOWS / 6-INCH
STANDARD PENETRATION TEST
BLOW
COUNT
2
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Very Firm to Very Dense Grayish
Brown Fine SAND (SP), Continued
Boring Terminated at 20 Feet
7
16
35
50
85
L E G A C Y TEST BORING RECORD JOB NO.20-1252
ENGINEERING, INC.
Geotechnical & Materials Engineering and Testing BORING NO.B1
Project 1820 Ocean Grove Drive Sheet 2 of
ELEV.
(FT)
DEPTH
(FT)MATERIAL DESCRIPTION
SO
I
L
SY
M
B
O
L
SA
M
P
L
E
NO
.
BLOWS / 6-INCH
STANDARD PENETRATION TEST
BLOW
COUNT
2
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Topsoil
Firm Grayish Brown Fine SAND with Trace of Concrete
Fragments (SP)
Firm Brown and Light Gray Fine SAND (SP)
Loose Brown Fine SAND (SP)
Very Firm to Very Dense Grayish
Brown Fine SAND (SP)
1
2
3
4
5
6
1
2
9
6
3
7
5
5
4
4
4
4
3
3
4
4
2
3
7
5
9
17
11
12
8
7
10
26
L E G A C Y TEST BORING RECORD JOB NO.20-1252
ENGINEERING, INC.
Geotechnical & Materials Engineering and Testing BORING NO.B2
Project 1820 Ocean Grove Drive Sheet 1 of
Boring Location See Field Exploration Plan Boring Begun 10/19/20
Ground Elevation N/A Datum N/A Boring Completed 10/19/20
Groundwater Depth 4.9 Feet Driller DK
Length of Casing Set 5 Feet Casing Size 4 Inches Engineer J. Ellis II, P.E.
REMARKS:BORING & SAMPLING: ASTM D1586/CORE DRILLING: ASTM D2113
BLOW COUNT IS THE NUMBER OF BLOWS OF 140 LB. HAMMER
Ground Water Table FALLING 30 IN. REQUIRED TO DRIVE 1.4 IN. I.D. SAMPLER 1 FT.
ELEV.
(FT)
DEPTH
(FT)MATERIAL DESCRIPTION
SO
I
L
SY
M
B
O
L
SA
M
P
L
E
NO
.
BLOWS / 6-INCH
STANDARD PENETRATION TEST
BLOW
COUNT
2
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Very Firm to Very Dense Grayish
Brown Fine SAND (SP), Continued
Boring Terminated at 20 Feet
7
17
35
50-5"
50-5"
L E G A C Y TEST BORING RECORD JOB NO.20-1252
ENGINEERING, INC.
Geotechnical & Materials Engineering and Testing BORING NO.B2
Project 1820 Ocean Grove Drive Sheet 2 of
ELEV.
(FT)
DEPTH
(FT)MATERIAL DESCRIPTION
SO
I
L
SY
M
B
O
L
SA
M
P
L
E
NO
.
BLOWS / 6-INCH
STANDARD PENETRATION TEST
BLOW
COUNT
2
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Topsoil
Loose Grayish Brown Fine SAND (SP)
Very Loose Gray Fine SAND (SP)
Loose Light Gray Fine SAND (SP)
Firm Light Gray Fine SAND (SP)
Very Firm to Very Dense Grayish Brown Fine SAND with
Silt (SP-SM)
1
2
3
4
5
6
1
3
4
3
2
2
1
3
2
3
4
4
2
3
4
8
6
4
7
4
11
18
7
3
7
7
11
29
L E G A C Y TEST BORING RECORD JOB NO.20-1252
ENGINEERING, INC.
Geotechnical & Materials Engineering and Testing BORING NO.B3
Project 1820 Ocean Grove Drive Sheet 1 of
Boring Location See Field Exploration Plan Boring Begun 10/19/20
Ground Elevation N/A Datum N/A Boring Completed 10/19/20
Groundwater Depth 4.8 Feet Driller DK
Length of Casing Set 5 Feet Casing Size 4 Inches Engineer J. Ellis II, P.E.
REMARKS:BORING & SAMPLING: ASTM D1586/CORE DRILLING: ASTM D2113
BLOW COUNT IS THE NUMBER OF BLOWS OF 140 LB. HAMMER
Ground Water Table FALLING 30 IN. REQUIRED TO DRIVE 1.4 IN. I.D. SAMPLER 1 FT.
ELEV.
(FT)
DEPTH
(FT)MATERIAL DESCRIPTION
SO
I
L
SY
M
B
O
L
SA
M
P
L
E
NO
.
BLOWS / 6-INCH
STANDARD PENETRATION TEST
BLOW
COUNT
2
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Very Firm to Very Dense Grayish Brown Fine SAND with
Silt (SP-SM), Continued
Boring Terminated at 20 Feet
7
20
50-5"50-5"
L E G A C Y TEST BORING RECORD JOB NO.20-1252
ENGINEERING, INC.
Geotechnical & Materials Engineering and Testing BORING NO.B3
Project 1820 Ocean Grove Drive Sheet 2 of
ELEV.
(FT)
DEPTH
(FT)MATERIAL DESCRIPTION
SO
I
L
SY
M
B
O
L
SA
M
P
L
E
NO
.
BLOWS / 6-INCH
STANDARD PENETRATION TEST
BLOW
COUNT
2
L E G A C Y
ENGINEERING, INC
Geotechnical & Materials Engineering and Testing
20-1252 ii November 2, 2020
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
1820 Ocean Grove Drive
APPENDIX B
KEY TO SOIL CLASSIFICATION
FIELD AND LABORATORY TEST PROCEDURES
Consulting Engineering Services
The Ellis Family Has Been Serving the Engineering and Construction Industries Since 1939
KEY TO SOIL CLASSIFICATION
CORRELATION OF PENETRATION WITH RELATIVE DENSITY & CONSISTENCY
SANDS AND GRAVEL SILTS AND CLAYS
BLOW COUNT RELATIVE DENSITY BLOW COUNT CONSISTENCY
0-4 VERY LOOSE 0-2 VERY SOFT
5-10 LOOSE 3-4 SOFT
11-20 FIRM 5-8 FIRM
21-30 VERY FIRM 9-15 STIFF
31-50 DENSE 16-30 VERY STIFF
OVER 50 VERY DENSE 31-50 HARD
OVER 50 VERY HARD
PARTICLE SIZE IDENTIFICATION
(UNIFIED CLASSIFICATION SYSTEM)
CATEGORY DIMENSIONS
Boulders Diameter exceeds 12 inches
Cobbles 3 to 12 inches
Gravel Coarse – 0.75 to 3 inches in diameter
Fine – 4.76 mm to 0.75 inch diameter
Sand
Coarse – 2.0 mm to 4.76 mm diameter
Medium – 0.42 mm to 2.0 mm diameter
Fine – 0.074 mm to 0.42 mm diameter
Silt and Clay Less than 0.074 mm (invisible to the naked eye)
MODIFIERS
These modifiers provide our estimate of the amount of minor constituent
(sand, silt, or clay size particles) in the soil sample
PERCENTAGE OF MINOR CONSTITUENT MODIFIERS
0% to 5% No Modifier
5 % to 12 % With Silt, With Clay
12% to 30% Silty, Clayey, Sandy
30% to 50% Very Silty, Very Clayey, Very Sandy
APPROXIMATE CONTENT OF OTHER
MODIFIERS
APPROXIMATE CONTENT OF
COMPONENTS (SHELL, GRAVEL, ETC.) ORGANIC COMPONENTS
0% to 5% TRACE 1 to 2%
5% to 12% FEW 2% to 4%
12% to 30% SOME 4% to 8%
30% to 50% MANY >8%
FIELD AND LABORATORY TEST PROCEDURES
Penetration Borings
The penetration borings were made in general accordance with ASTM D 1586-67, “Penetration Test and
Split-Barrel Sampling of Soils”. Each boring was advanced to the water table by augering and, after
encountering the groundwater table, further advanced with a rotary drilling technique that uses a
circulating bentonite fluid for borehole flushing and stability. At two-foot intervals within the upper 10
feet and at five-foot intervals thereafter, the drilling tools were removed from the borehole and a split-
barrel sampler inserted to the borehole bottom. The sampler was then driven 18 inches into the material
using a 140-pound SPT hammer falling, on the average, 30 inches per hammer blow. The number of
hammer blows for the final 12 inches of penetration is termed the “penetration resistance, blow count, or
N-value”. This value is an index to several in-place geotechnical properties of the material tested, such as
relative density and Young’s Modulus.
After driving the sampler 18 inches (or less, if in hard rock or rock-like material) at each test interval, the
sampler was retrieved from the borehole and a representative sample of the material within the split-barrel
was placed in a watertight container and sealed. After completing the drilling operations, the samples for
each boring were transported to our laboratory where our Geotechnical Engineer examined them in order
to verify the driller’s field classifications. The samples will be kept in our laboratory for a period of two
months after submittal of formal written report, unless otherwise directed by the Client.
Soil Classification
Soil samples obtained from the performance of the borings were transported to our laboratory for
observation and review. An engineer, registered in the State of Florida and familiar with local geological
conditions, conducted the review and classified the soils in accordance with ASTM 2488. The results of
the soil classification are presented on the boring records.