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March 19, 2018
Mr. Clyde O'Brien
5065 NW Edgarton Terrace
Port St. Lucie, Florida
Subject: Soil Exploration
Proposed One -Story Residence and Detached Garage
2959 Yates Road, Fort Pierce, Florida
GFA Project No. 18-4477.01
Dear Mr. O'Brien:
GFA International, Inc. (GFA) performed soil testing with three auger borings and hand cone
penetrometers at the above referenced project site. The subsurface exploration activities were
performed in accordance with Chapter 18 of the Florida Building Code (latest edition) and applicable
ASTM standards. Detailed information for the subsurface conditions encountered in the borings are
contained on the auger boring logs attached to this letter.
Based on the test results, the soil on which the referenced structure is to rest is capable of providing a
safe bearing capacity of 2,500 psf subject to the limitations noted herein. We recommend that the
bottom of the footings bear at a depth of at least 12 inches below finish grade. The depth should be
measured from the lowest adjacent grade. We also recommend a minimum footing width of 18 inches
for spread footings and 16 inches for monolithic footings, but not less than 8 inches more than the
width of the imposed wall.
This report does not state or imply that the foundation soils at the bearing level will remain in the
original condition in which they were found during the subsurface exploration activities. Exposure to
the environment may weaken the foundation soils at the bearing level if the foundation excavations
remain open for a long period of time, or if the foundation soils are exposed to rainfall. Consequently,
it is recommended that the excavations for the wall and column footings be performed to final grade
and footings be constructed as soon as possible to reduce the potential for deterioration of the
bearing soils.
GFA estimates the site is at or near final grade. It is also recommended that the 2 feet of soil below
existing grade, the bottom of all new footing excavations and slabs, and all fill material be compacted
to at least 95 percent of the modified Proctor (ASTM D 1557) maximum dry density prior to the
placement of foundation concrete. If compaction cannot be attained due to persistent wetness, the
presence of the water table near the bottom of the footing excavation, or due to silty/clayey soil
"pumping" during compaction, GFA recommends undercutting the wet soils below bottom of footing
followed by replacement with FDOT No...57.stone. The rock fill should be compacted and tamped into
the excavation and tested by a GFA representative by performing in -place density tests or using a
hand cone penetrometer or probe rod.
607 NW Commodity Cove - Port St. Lucie, Florida 34986 • (772) 924.3575. - (772) 924.3580 (fax) w+�y aam com
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OFFICES THROUGHOUT FLORIDA "J
Proposed One -Story Residence and Detached Garage
2959 Yates Road, Fort Pierce, Florida
GFA Project No. 18-4477.01
March 19, 2018
Foundations and any below grade remains of any structures that are within the footprint of the new
construction should be removed so as to not affect the proposed construction.
GFA should be provided the opportunity to review the final foundation specifications and design
drawings to determine if GFA's recommendations have been properly interpreted, communicated, and
implemented. If GFA is not afforded the opportunity to participate in construction related aspects of
foundation installation as recommended in this report or any report addendum, GFA will accept no
responsibility for the interpretation of our recommendations made in this report or on a report
addendum for foundation performance.
We appreciate the opportunity to be of service to you on this project and look forward to a continued
association. Please contact the undersigned if you have any questions or comments, or if we may
further assist you as your plans proceed
RespectfuVatifimitteo,
GFA It }� r g.'rri
Florid' Cell; ifl" a #AythorVtion No. 4930
Jo&.K6nt, P.E.
SeibWVoiecLgReineer :' 0,
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AttachQ `-1 RlPi'iion Plan
Auger Boring Logs (3)
Notes Related to Test Borings
Distribution: Mr. Clyde O'Brien —1 pdf
g an Collie, E.I.
P je Manager
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Test Location Plan: 2959 Yates Rd, Fort Pierce, FL
- Y•: AµP
--Approximate Auger Boring (AB) Locations
Since 1988
AUGER BORING LOGS WITH HAND CONE PENETROMETER (HCP) TESTS
Client: Clyde O'Brien
Project No: 18-4477.01
Project: 2959 Yates Rd.
Lab No:
Fort Pierce, FL
Test Date: 3/13/2018
Elevation: Existing Grade
Technician: PM/WG
TEST LOCATION: AB — 1 N27.41241 ° W80.371150
HCP
Depth (feet)
Description (color, texture, consistency, remarks)
Depth
Reading
0-2
Gray fine sand SP
1
25
2'- 4
Light gray fine sand SP
2
80+
4 - 6.5
Gray fine sand, little clay SP-SC)
3
80+
6.5 - 10
Brown fine sand, trace clay SP
4
80+
5
80+
6
80+
7
80+
8
80+
9
80+
10
80+
Water table at 5.8 feet below ground surface
TEST LOCATION: AB — 2 N27.41241 ° W80.371190
HCP
Depth (feet)
Description (color, texture, consistency, remarks)
Depth
Reading
0-3
Light gray fine sand SP
1
50
3-6
Gray fine sand, little clay SP-SC)
2
80+
6-8
Brown fine sand, trace clay SP
3
30
8-10
Gray fine sand, little clay SP-SC)
4
50
5
60
6
80+
7
60
8
80+
9
80+
10
80+
Water table at 6 feet below ground surface
000- Since 1988
AUGER BORING LOGS WITH HAND CONE PENETROMETER (HCP) TESTS
Client: Clyde O'Brien
Project No: 18-4477.01
Project: 2959 Yates Rd.
Lab No:
Fort Pierce, FL
Test Date: 3/13/2018
Elevation: Existing Grade
Technician: PM/WG
TEST LOCATION: AB-3 N27.412240 W80.371090
HCP
Depth (feet)
Description (color, texture, consistency, remarks)
Depth
Reading
0-4
Light gray fine sand SP
1
30
4-6
Gray fine sand, little silt and clay SP-SC)
2
80+
6 - 10
Brown fine sand, trace clay SP
3
80+
4
80+
5
80+
6
80+
7
60
8
70
9
60
10
60
Water table at 5.7 feet below ground surface
NOTES RELATED TO
RECORDS OF TEST BORING AND
GENERALIZED SUBSURFACE PROFILE
1. Groundwater level was encountered and recorded (if shown) following the completion of the soil test boring on
the date indicated. Fluctuations in groundwater levels are common; consult report text for a discussion.
2. The boring location was identified in the field by offsetting from existing reference marks and using a cloth tape
and survey wheel.
3. The borehole was backfilled to site grade following boring completion, and patched with asphalt cold patch mix
when pavement was encountered.
4. The Record of Test Boring represents our interpretation of field conditions based on engineering examination of
the soil samples.
5. The Record of Test Boring is subject to the limitations, conclusions and recommendations presented in the Report
text.
6. "Field Test Data" shown on the Record of Test Boring indicated as 11/6 refers to the Standard Penetration Test
(SPT) and means 11 hammer blows drove the sampler 6 inches. SPT uses a 140-pound hammer falling 30 inches.
7. The N-value from the SPT is the sum of the hammer blows required to drive the sampler the second and third 6-
inch increments.
8. The soil/rock strata interfaces shown on the Records of Test Boring are approximate and may vary from those
shown. The soil/rock conditions shown on the Records of Test Boring refer to conditions at the specific location
tested; soil/rock conditions may vary between test locations.
9. Relative density for sands/gravels and consistency for silts/clays are described as follows:
SPT
CPT
SANDS/GRAVELS
SPT
CPT
SILTS/CLAYS
BLOWS/FOOT
KG1CM2
RELATIVE DENSITY
BLOWS/FOOT
KG/CM2
CONSISTENCY
0-4
0-16
Very loose
0-1
0-3
Very soft
5-10
1740
Loose
2-4
4-6
Soft
11-30
41-120
Medium Dense
5-8
7-12
Firm
31-50
121-200
Dense
9-15
13-25
Stiff
50+
over 200
Very Dense
16-30
25-50
Very stiff
>30
>50
Hard
10. Grain size descriptions are as follows:
NAME
SIZE LIMITS
Boulder
12 Inches or more
Cobbles
3 to 12 Inches
Coarse Gravel
3/4 to 3 Inches
Fine Gravel
No. 4 sieve to inch
Coarse Sand
No. 10 to No. 4 sieve
Medium Sand
No. 40 to No. 10 sieve
Fine Sand
No. 200 to No. 40 sieve
Fines
Smaller than No. 200 sieve
11. Definitions related to adjectives used in soil/rock descriptions:
PROPORTION
ADJECTIVE
APPROXIMATE ROOT DIAMETER
ADJECTIVE
<5%
Trace
Less than 1/32"
Fine roots
5% to 12%
Little
1/32" to '/4"
Small roots
12% to 30%
Some
'/4" to V
Medium roots
30% to 50%
And
Greater than V
Large roots
Organic Soils: Soils containing vegetable tissue in various stages of decomposition that has a fibrous to amorphous texture,
usually a dark brown to black color, and an organic odor.
Organic Content <25%: Slightly to Highly Organic; 25% to 75%: Muck; >75%: Peat
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