Public Safety Pavement Repairs and Site Improvements

Location:	Georgia
Posted:	Apr 21, 2026
Due:	May 26, 2026
Agency:	City of Duluth
Type of Government:	State & Local
Category:	Z - Maintenance, Repair or Alteration of Real Property
Publication URL:	To access bid details, please log in.

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Report of Subsurface Exploration

and Geotechnical Engineering Evaluation

Stair Settlement and Pavement Rehabilitation

Duluth Public Safety Center

Duluth, Georgia

Geo-Hydro Project Number 253175.20

Prepared for POND

February 17, 2026

Mr. Kevin Hendrix, P.E.

Pond

55 Ivan Allen Jr. Boulevard

Suite 850

Atlanta, Georgia 30308

Dear Mr. Hendrix:

February 17, 2026

Report of Subsurface Exploration

and Geotechnical Engineering Evaluation

Stair Settlement and Pavement Rehabilitation

Duluth Public Safety Center

Duluth, Georgia

Geo-Hydro Project Number 253175.20

Geo-Hydro Engineers, Inc. has completed the authorized subsurface exploration for the above referenced

project. The scope of services for this project was outlined in proposal number 253175.P0 dated

December 30, 2025.

Project Information

The Duluth Public Safety Center is located at 3276 Buford Highway in Duluth, Georgia. Figure 1 in the

Appendix shows the approximate location of the facility.

The existing building is a one-story structure with a daylighted basement level. The northwest side of the

building includes stairs, which appear to be settling relative to the first floor elevation, and some stairs have

also tilted according to the information outlined in

the Structural Site Observation Report produced by

Pond dated July 8, 2025.

The overall project will include stabilizing or

rehabilitating the steps, and rehabilitation of the

existing access drives and parking lots. The existing

parking lots and access drives, including landscape

islands and related curbing, occupy approximately

8,200 square yards. The documents provided to us

indicate some noticeable deformations including

settlement around a drop inlet, standing water due to

localized subsidence, and a large crack between the

drive aisle and the parking stalls. The annotated

aerial photograph to the right shows the approximate

property limits and current site conditions. The

photographs on the following page show the

condition of the stairs at the time of our field

exploration as well as evidence of exterior floor slab

subsidence at the building wall.

Stairs

400 Chastain Center Boulevard, Suite 430 • Kennesaw, Georgia 30144

o: 770.426.7100 • www.geohydro.com

Stair Settlement and Pavement Rehabilitation • Duluth Public Safety Center - Duluth, Georgia

Project Number 253175.20

Exploratory Procedures

The subsurface exploration consisted of three hand auger borings within the stairs area and five hand auger

borings within the parking lots and access drives. The borings were performed at the approximate locations

shown on Figure 2 in the Appendix. The boring locations were selected based on visual observations of

the stairs and pavement areas, and each test location was recorded using a handheld GPS unit.

Dynamic cone penetrometer testing (ASTM STP-399) was performed at select depths in the hand auger

borings. Soil samples obtained from hand auger boring operation were examined and classified in general

accordance with ASTM D2488 (Visual-Manual Procedure for Description of Soils). Soil classifications

include the use of the Unified Soil Classification System described in ASTM D2487 (Classification of Soils

for Engineering Purposes). The soil classifications also include our evaluation of the geologic origin of the

soils. Evaluations of geologic origin are based on our experience and interpretation and may be subject to

some degree of error.

February 17, 2026 | 2

Stair Settlement and Pavement Rehabilitation • Duluth Public Safety Center - Duluth, Georgia

Project Number 253175.20

Descriptions of the soils encountered, groundwater conditions, penetration resistances, and other pertinent

information are provided in the hand auger log included in the Appendix.

Regional Geology

The project site is located in the Southern Piedmont Geologic Province of Georgia. Soils in this area have

been formed by the in-place weathering of the underlying crystalline rock, which accounts for their

classification as “residual” soils. Residual soils near the ground surface that have experienced advanced

weathering frequently consist of red brown clayey silt (ML) or silty clay (CL). The thickness of this

surficial clayey zone may range up to roughly 6 feet. For various reasons, such as erosion or local variation

of mineralization, the upper clayey zone is not always present.

With increased depth, the soil becomes less weathered, coarser grained, and the structural character of the

underlying parent rock becomes more evident. These residual soils are typically classified as sandy

micaceous silt (ML) or silty micaceous sand (SM). With a further increase in depth, the soil eventually

becomes quite hard and take on an increasing resemblance to the underlying parent rock. When these

materials have a standard penetration resistance of l00 blows per foot or greater, they are referred to as

partially weathered rock. The transition from soil to partially weathered rock is usually a gradual one, and

may occur at a wide range of depths. Lenses or layers of partially weathered rock are not unusual in the

soil profile.

Partially weathered rock represents the zone of transition between the soil and the indurated metamorphic

rocks from which the soils are derived. The subsurface profile is, in fact, a history of the weathering process

that the crystalline rock has undergone. The degree of weathering is most advanced at the ground surface,

where fine-grained soil may be present. Conversely, the weathering process is in its early stages

immediately above the surface of relatively sound rock, where partially weathered rock may be found.

The thickness of the zone of partially weathered rock and the depth to the rock surface have both been

found to vary considerably over relatively short distances. The depth to the rock surface may frequently

range from the ground surface to 80 feet or more. The thickness of partially weathered rock, which overlies

the rock surface, may vary from only a few inches to as much as 40 feet or more.

Soil Test Boring Summary

Starting at the floor surface, hand auger borings HA-1, HA-2, and HA-3 encountered approximately 4¾ to

6¼ inches of concrete underlain by approximately 6 to 7½ inches of graded aggregate base (GAB). Hand

auger borings HA-4 through HA-8 initially encountered approximately 2 to 3½ inches of asphalt underlain

by approximately 3¼ to 7½ inches of GAB. Reinforcing steel was encountered within the layer of GAB in

borings HA-1 and HA-2, resulting in a boring offset.

Beneath the surface materials, all hand auger borings encountered fill materials extending to depths ranging

from approximately 1½ to greater than 10 feet. Boring HA-3 was terminated in fill at a depth of

10 feet, while borings HA,4, HA-5, and HA-6 were terminated in fill materials at depth of 4 feet. The fill

February 17, 2026 | 3

Stair Settlement and Pavement Rehabilitation • Duluth Public Safety Center - Duluth, Georgia

Project Number 253175.20

materials were classified as clayey sand and silty sand. Dynamic cone penetrometer resistances recorded

in the fill ranged from 4 to 17 blows per increment.

Beneath the fill materials, hand auger borings HA-1, HA-2, HA-7, and HA-8 encountered residual soils

typical for the Piedmont region. The residual soils were classified as silty sand with dynamic cone

penetrometer resistances ranging from 9 to greater than 25 blows per increment.

At the time of the exploration, groundwater was not encountered in the hand auger borings. The borings

were backfilled with soil cuttings after the groundwater check and patched with fresh concrete or cold patch

asphalt as appropriate. It should be noted that groundwater levels will fluctuate depending on yearly and

seasonal rainfall variations.

For more detailed descriptions of subsurface conditions, please refer to the hand auger logs included in the

Appendix.

Hand Auger Boring Summary

Boring

Concrete

Thickness

(inches)

Asphalt

Thickness

(inches)

GAB

Thickness

(inches)

HA-1

HA-2

6¼

6½

HA-3

4¾

7½

HA-4

3½

7½

HA-5

2¼

3¼

HA-6

4½

HA-7

2¾

6¾

HA-8

3¼

6¾

All Depths in this Summary Table are Approximate

NE: Not Encountered

GAB: Graded Aggregate Base

Bottom of Fill

(feet)

>10

1½

Depth to Hand

Auger Refusal

(feet)

VISUAL PAVEMENT EVALUATION

Hand Auger

Termination

Depth (feet)

Depth to

Groundwater

(feet)

February 17, 2026 | 4

This is the opportunity summary page. It provides an overview of this opportunity and a preview of the attached documentation.

Description	Opening Date/Time	Closing Date/Time
Public Safety Pavement Repairs and Site Improvements Geotechnical Report	April 21, 2026 :	May 26, 2026 1:45 PM

Public Safety Pavement Repairs and Site Improvements

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See also