SW3190704_GTA results of Seasonal High-Water Table_3/12/2020

GTA ASSOCIATES, INC.
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November 25, 2019
Coulston Enterprises, Inc.
8332 Regent Parkway
Fort Mill, South Carolina 29715
Attn: Mr. Earl Coulston
Re: Results of Seasonal High -Water Table
Skylantl Drive Tofvnhomes
S. Skyland Drive
Mt. Pleasant, Caban-us County, North Carolina
Dear Mr. Coulston:
As requested, GTA Associates, Inc. (GTA) visited the subject property on September 13,
2019 to install a temporary monitoring well in the proposed detention basin and evaluate the
potential groundwater levels at the above reference project site. The field exploration consisted of
performing one hand auger boring (P-1) to a depth of approximately 10 feet below the existing
ground surface elevation in the proposed detention basin area.
Once the hand auger boring was extended 10 feet, a slotted PVC standpipe was installed in
the auger hole. The outside of the pipe was then backfilled with sand. The approximate location of
the temporary PVC standpipe is shown on the attached "Temporary Monitoring Well Plan."
Samples collected from the hand auger boring was submitted to GTA's laboratory for visual
observations. Material descriptions are visual approximations in accordance with the Unified Soil
Classification System (USCS). At the surface of P-1, native residual soils were encountered. The
residual soils generally consist of stiff to very stiff lean clay (CL) in the upper 3 feet underlain by
sandy silt (ML) in the upper 10 feet.
Based on the "Grading Plan" prepared by American Engineering dated August 21, 2019, the
ground surface elevation at P-1 is approximately Elevation 679 feet above mean sea level (MSL).
Please note that the temporary monitoring well has not been surveyed. Please refer to Table 1 below
for the results of the water level readings.
710 Peninsula Lane, Suite B, Charlotte, NC 28273 Phone: [phone] Fax: [phone]
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Ksit us on the rseh at nTSTs:gtaengcom

Coulston Enterprise, Inc.
Re: Skyland Drive Townhomes, Mt. Pleasant, N. C.
November 25, 2019
TABLE 1: WATER LEVEL READINGS
GROUND
DEPTH OF PVC
WATER
WATER
'WATER
LOCATION
SURFACE
STANDPIPE
LEVEL
LEVEL
LEVEL
ELEVATION
(ft)
READINGS
READINGS
READINGS
ft
9-13-19
10-11-19
11-21-19
P-1
1 679
10
DRY
DRY
DRY
Based on the results of our visual observations, groundwater was not encountered in the
temporary PVC standpipe on the dates evaluated. In addition, there were no signs of mottling
(discoloration of the soils) and no signs of a seasonal high-water mark at P-1. Please be advised that
groundwater levels are expected to fluctuate with changes in precipitation, drainage, and other
factors. Based on the results of the water level readings and our visual observations, groundwater
was not encountered to a depth of Elevation 669 feet (MSL) on the dates evaluated.
GTA Associates, Inc. appreciates the opportunity to be of assistance to you. If you have any
questions regarding this report, please feel free to contact our office at [phone].
Sincerely,
GTA ASSOCIATES, INC.
VA /, d%
John P. Wille, P.E.
Vice President
FEE
Attachments:
Temporary Monitoring Well Plan, Figure 1
2

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