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Environmental - Geotechnical - Construction Materials Testing - Threshold and Special Inspections - Plan Review & Code Compliance
September 23, 2016
Ms. Sherry Anderson
18749 Alexander Road RECEIVED
Walton Hills, OH 44146
RE: Soil Exploration - Proposed Two -Story Residence JAN 10 2018
10725 S Ocean Dr. #482, St. Lucie County, FL ST. Lucie County, Permitting
GFA Project # 16-2018.00
GFA International performed soil testing with one Standard Penetration Test (SPT) boring
and one auger boring with hand cone penetrometers at the above referenced project. Based
on the test results, the soil on which the referenced structure is to rest is capable of
sustaining a safe bearing capacity of 2,500 psf. The subsurface exploration activities were
performed in accordance with Chapter 18 of the Florida Building Code (latest addition) and
applicable ASTM standards. For detailed information on subsurface conditions encountered,
please refer to the logs attached to this letter.
We recommend that the bottom of the footings be founded at a depth of at least 12 inches
below finish grade. The depth shall 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 constructed as soon as possible to
minimize potential damage of the bearing soils. GFA estimates the site is at or near final
grade. It is also recommended that the 2 feet below existing grade, the bottom of all new
footing excavations and slabs, and all fill material, be compacted to a minimum density of
95% of the Modified Proctor (ASTM D-1557), prior to the placement of the concrete for the
footings.
If compaction cannot be attained due to persistent wetness or the water table near the bottom
of the footing excavation, GFA recommends undercutting below bottom of footing and
replacement with No. 57 stone for subgrade that cannot be compacted. The rock fill should
be compacted and tamped into the excavation and inspected and verified by a representative
from GFA, and tested with hand cone penetrometers, probe rods, or density tests.
521 NW Enterprise Drive - Port St. Lucie, Florida 34986 - (772) 924.3575 - (772) 924.3580 (fax) - www.teamgfa.com
OFFICES THROUGHOUT FLORIDA
Proposed Two -Story Residence September 23, 2016
10725 S Ocean Dr. 482, St. Lucie County, FL
GFA Project# 16-2018.00 _
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 structures.
Sincerely,
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Manager
Attachments: Test Location Plan, Standard Penetration Test (SPT) Boring (1),
Auger Boring (AB) Log (1), Notes Related to Test Borings
Copies: Client (2)
GFi
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Legend
'FRNAT�Ot�
Test Location Plan
10725 S Ocean Dr. 482
St. Lucie County, FL
GFA Project No. 16-2018.00
Approximate Standard Penetration Test (SPT) Boring & Auger Boring (AB) Locations
4
GFA INTERNATIONAL
521 N.W. ENTERPRISE DRIVE, PORT ST. LUCIE, FLORIDA 34986
PHONE: (772) 924-3575 - FAx: (772) 924-3580
STANDARD PENETRATION TEST BORING (ASTM D-1586)
Client: Sherry Anderson Project No.:16-2018.00
Lab No.:
Project: 10725 S Ocean Dr. 482 Page: 1 of 1
St. Lucie County, FL Date: 9/22/2016
Elevation: Existing Grade Drill Rig: Simco-24
Water Level: 2.0 feet after 0 hours Drilling Fluid commenced at depth of 10 feet Field Party: PNVES
Hand Auger with Hand Cone Pentrometer Test (HCP in kst) performed in top 4 feet
TEST LOCATION: SPT -1 N27.271480 W80.205830
Laboratory Tests
Depth
Blows/
N
Sample
Layer:
USCS
Description
Passing
Moisture
Organic
(feet)
6 in.
Value
No.
From/to
No. 200
Content
Content
0
0-1
SP
Gray fine sand
HCP=
15
1
1-3
SP
Brown fine sand
HCP=
20
HCP=
80+
2
3-16
SP
Gray fine sand, trace shell
---- 4
HCP=
80+
----
9
5
.....11.................
17
28
3
--- 6
20
................
...
4
........................
-- _-
10
16
4
12
8
................
...
10
-- --
1'0
20
5
13
10
.................
...
----
10
12
11
_--
.....I ....................
13
25
6
14
12
.................
....... ...
6
13
...........................
10
16
7
__-
14
12
.................
..........
10
153
......1.....................
--
12
25
8
16
...-15.................
Borin Terminated at 16 feet
g
17
........
.......
18
........
.......
19
........
.......
0-� Since 1988
Florida's Leading Engineering Source
AUGER BORING LOGS WITH HAND CONE PENETROMETER (HCP) TESTS
Client: Sherry Anderson
Project: 10725 S Ocean 482
St. Lucie County, FL
Elevation: Existing Grade
Project No:
Lab No:
Test Date:
Technician:
16-2018.00
9/22/2016
PM/ES
TEST LOCATION: AB —1 N27.27161 ° W80.205860
HCP
Depth (feet)
Description (color, texture, consistency, remarks)
Depth
Reading
0-1
Brown fine sand SP
1
10
1 - 2
fine sand SP
2
10
2-3
—Gray
Brown fine sand SP
3
40
3-10
Gray fine sand, trace shell SP
4
80+
5
80+
6
80+
7
80+
8
20
9
40
10
30
Water table at 2.3 feet below ground surface
I
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
KG/CM2
RELATIVE DENSITY
BLOWS/FOOT
KG/CM
CONSISTENCY
0-4
0-16
Very loose
0-1
0-3
Very soft
5-10
17-40
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
% 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'/<"
Small roots
12% to 30%
Some
'''A" 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