Attachment_A_-_Geotechnical_Report.pdf

GEOTECHNICAL INVESTIGATION REPORT

ANACOSTIA II WWPS ELECTRICAL UPGRADE

CAPITOL HEIGHTS, MARYLAND

Findling Project No. 20-1045-06

WSSC Contract No. PM0002A20 – Task 6

Prepared for:

SHAH & ASSOCIATES, INC.

416 North Frederick Ave

Gaithersburg, Maryland 20877

September 07, 2021

Findling Inc.

FINDLING, INC.

3401 Carlins Park Drive, Baltimore, MD 21215

TEL. : 410-367-1400 FAX: 410-466-6867

September 07, 2021

Shah & Associates, Inc.

416 North Frederick Ave Gaithersburg, MD 20877

Attention: Dr. Kanu Shah, Ph.D., P.E.

President

Re: Geotechnical Investigation Report

Anacostia II WWPS Electrical Upgrade Capitol Heights, Maryland

Dear Dr. Shah:

Findling, Inc. is pleased to submit this report containing the results of the geotechnical investigation for the proposed replacement of two transformers, and 13.8 kV and 4.16 kV switchgear at Anacostia II Wastewater Pumping Station, Capitol Heights, MD (see Figure 1: Site Vicinity Map, in the Appendix). The work described within the report was performed in accordance with our proposal dated May 06, 2021.

We wish to advise you that we will store the soil samples obtained from the soil test borings for a period of thirty (30) days from the date of this letter, during which time they will be available for inspection. After that time the samples will be discarded unless another disposition is requested.

We appreciate the opportunity to be of service to you on this project. If you have any questions, please call us.

Sincerely, Dipesh Tajhya

Geotechnical Engineer

TEL: 410-367-1400

FAX: 410-466-6867

info@findlinginc.com

3401 Carlins Park Drive, Baltimore, Maryland 21215

TABLE OF CONTENTS

1.0 INTRODUCTION

2.0 PROJECT DESCRIPTION

2.1 Existing Condition

2.2 Proposed Construction

3.0 PURPOSE AND SCOPE

4.0 SUBSURFACE INVESTIGATION

4.1 Field Investigation

4.2 Soil Test Borings

4.3 Laboratory Testing

5.0 SUBSURFACE CONDITIONS

5.1 Site Geology

5.2 Soil Conditions

5.3 Groundwater

6.0 SEISMIC SITE CLASSIFICATION

7.0 CONCLUSIONS AND RECOMMENDATIONS

7.1 Foundation Subgrade

7.2 Concrete Pad

8.0 GENERAL GRADING CONSIDERATIONS

8.1 Undercutting

8.2 Proofrolling

8.3 Fill Selection, Placement, And Compaction

8.4 Construction Dewatering

8.5 Excavation Considerations

9.0 ENVIRONMENTAL CONSIDERATIONS

10.0 REMARKS

APPENDIX

GEOTECHNICAL INVESTIGATION REPORT

Capitol Heights, Maryland

1.0 INTRODUCTION

Findling, Inc. is pleased to submit this report containing the results of the geotechnical investigation conducted for the proposed replacement of two transformers, and 13.8 kV and 4.16 kV switchgear at Anacostia II Wastewater Pumping Station, Capitol Heights, MD (see Figure 2: Project Location Map, in the Appendix). This work was conducted for Shah & Associates, Inc. in accordance with our proposals dated May 06, 2021.

2.0 PROJECT DESCRIPTION

2.1 Existing Condition

The location of the proposed construction currently consists of two concrete pads, each supporting two 13.8 kV switchgears, an oil-filled 13.8 kV-4.16 kV step-down transformer, and a 4.16 kV switchgear (Figure 3: Existing Site Condition). Two underground 13.8 kV feeders are emanating from Pepco’s Bladensburg Substation and one overhead 13.8 kV feeder emanating from Pepco’s Tuxedo Substation connected to these 13.8 kV switchgears.

2.2 Proposed Construction

The project consists of electrical equipment upgrades related to the replacement of two transformers, and 13.8 kV and 4.16 kV switchgear including associated electrical protection systems, data transmission of monitoring, metering, and alarm signals to Parkway WRRF SCADA system, battery system, and associated ducts or underground feeders and associated cables, and all appurtenant equipment. In addition, design of HVAC in IPA structures and foundations for 13.8 kV and 4.16 kV switchgear and two transformers.

3.0 PURPOSE AND SCOPE

The purpose of this geotechnical investigation was to determine the subsurface conditions in the vicinity of the proposed construction and prepare a report containing geotechnical-related design and construction considerations for the proposed project. The report is based on the evaluation of three test borings performed on the project site, available geological data, and our experience in the area

Initially, five borings B-1 to B-5 were marked in the vicinity of the proposed construction. Later, after discussing with the representative of WSSC and Shah & Associates, B-2 and B-5 were eliminated. Three soil test borings, B-1, B-3, and B-4 were

Capitol Heights, Maryland Findling Project No. 20-1045-06

September 07, 2021 Page 2 of 7 drilled, as shown in Figures 4: Boring Location Plan, in the Appendix. The borings were extended to a depth ranging from 20 feet to 25 feet below the existing grade. Following the completion of the fieldwork, the scope of work included conducting laboratory tests in order to classify and establish engineering properties of the underlying materials.

Environmental Investigation for determining if any site-specific health and safety or soil handling requirements that are needed during construction will be addressed in the subsequent report.

4.0 SUBSURFACE INVESTIGATION

4.1 Field Investigation

Prior to the drilling operation, the public utilities were marked and cleared by “Miss Utility”. A Private Utility Locator contracted by WSSC marked the utilities that were not cleared by Miss Utility. The three borings, B-1, B-3, and B-4, were drilled at the site, as shown in Figure 3: Boring Location Plan, in the Appendix. The boring locations were reviewed by representatives of Shah & Associates. The borings were extended to a depth ranging from 20 feet to 25 feet below the existing grade. The test borings were monitored for groundwater level during the drilling operations and were backfilled upon completion.

The boring data from the field investigation is summarized in Table 1 and included in the Appendix.

4.2 Soil Test Borings

The boreholes were advanced using hollow stem augers. Standard penetration tests (SPT) were conducted and split spoon samples were obtained at various intervals by driving a 1- 3/8-inch ID (2-inch OD) split-spoon sampler in accordance with ASTM D-1586 specifications. The sampler was first seated about 6 inches to penetrate through the loose cuttings and then driven an additional 1 foot with blows of a 140-pound hammer falling 30 inches. The number of hammer blows required to drive the sampler through the second and third 6-inch increment (i.e., the summation of the second and third blow counts) is typically designated as the Standard Penetration Resistance (N) value. The penetration resistance is an index of the soil’s strength, density, and behavior under applied loads.

A representative portion of each sample was placed in an airtight glass jar and was appropriately marked. All samples were sent to our laboratory for further evaluation and testing. The recovered soil samples were inspected and classified by a Geotechnical Engineer using the Unified Soil Classification System (USCS). The descriptions of the soils and conditions encountered at the test boring locations are presented on the Boring Logs and included in the Appendix.

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September 07, 2021 Page 3 of 7

4.3 Laboratory Testing

Soil samples recovered from the field exploration were transported to our soil testing laboratory and selected soil samples are being subjected to various testing to determine additional engineering characteristics of the existing on-site soils. The laboratory tests that were conducted on selected soil samples included natural moisture content test (ASTM D2216), Atterberg limits (ASTM D4318), sieve analysis (ASTM D422).

Moisture vs. Density relations (ASTM D698/1557) and CBR (ASTM D4429) tests were also performed on the bulk samples collected from test boring; B-1 and B-3 so as to evaluate the suitability of these materials for use as compacted fill and aid in the pavement design. All tests were performed in general accordance with the ASTM procedures. The results of these tests are summarized in Table 2 in the Appendix.

5.0 SUBSURFACE CONDITIONS

The Boring Logs included in the Appendix contain details related to the subsurface conditions encountered at the boring locations. It should be noted that stratification lines shown on the Boring Logs represent approximate transitions between material types.

Strata changes can occur gradually or at different levels than those shown on the Boring Logs and depict conditions at the indicated locations and depths at the time of our subsurface investigation program. Groundwater levels are variable and are influenced by the existing soil conditions, seasonal and climatic changes.

5.1 Site Geology

Geologically, the site lies in the Lowland Deposit Region. The soil in this area consists of deposits consisting of Gravel, Sand, Silt, and Clay that could have been deposited by the receding of the Anacostia River. The geology of the site is shown in Figure 5: Site Geology Map, in the Appendix.

5.2 Soil Conditions

As indicated previously, details of subsurface conditions disclosed by the borings are contained on the individual Boring Logs. The test borings revealed 4 to 5-inches of Asphalt pavement. Boring B-1 and B-3 were drilled at the proposed location of the transformer and switchgear pads. Boring B-4 was drilled near the proposed duct bank.

The Boring revealed Fill materials to a depth ranging from 5 feet to 13 feet and very loose to dense residual SAND with various percentages of Gravel and Silt to the maximum depth of drilling.

5.3 Groundwater

Groundwater was encountered in the borings at the depth ranging from 4.5+ feet to 11.5+ feet from the ground surface during the drilling operations and following the completion

Capitol Heights, Maryland Findling Project No. 20-1045-06

September 07, 2021 Page 4 of 7 of the drilling operations. However, fluctuations of the water table or the development of a perched water level at shallower depths above less permeable layers may occur depending upon the amount of precipitation and water runoff to the site from higher elevations during a wet season. Groundwater levels encountered during construction may differ from those encountered during our subsurface investigation, especially if construction is performed during a wet season of the year.

6.0 SEISMIC SITE CLASSIFICATION

The ASCE 7 Standard requires the use of Standard Penetration Test Resistance (test borings), Shear Wave Velocity (geophysical methods), and/or Undrained Shear Strength (soil laboratory testing) to categorize the Seismic Site Classification. Based on the explored soil properties in the test borings performed for this site, the Seismic Site Classification was determined to be Site Class E.

7.0 CONCLUSIONS AND RECOMMENDATIONS

The evaluations and recommendations presented in subsequent sections of this report were based on our understanding of the proposed construction and the general subsurface condition indicated by the test borings. Should the project characteristics be altered from those discussed or should different subsurface conditions be encountered during construction, this Office should be consulted, as the evaluations and recommendations presented herein may no longer be valid.

7.1 Foundation Subgrade

Based on the information provided to us, the existing two pads supporting Switchgear and Transformers will be demolished and new concrete pads will be reconstructed as shown in Figure 6, in the Appendix. The foundation subgrade will generally lie in Fill and consist of SAND with various percentages of Silt, Gravel, and Clays.

An allowable bearing pressure of 2,000 psf is recommended for the subgrade of concrete pads supporting the switchgears and transformers. The existing foundation subgrade must be inspected by an experienced Geotechnical Engineer, either using a Dynamic Cone Penetrometer (DCP) or other methods, in order to verify that the subgrade is capable of providing the recommended design bearing capacity. All footings should be placed at least 30 inches below the final exterior grade for frost protection.

7.2 Concrete Pad

The floor slab subgrades are expected to be Fill material consisting of SAND. The floor slab can be designed as a conventional slab-on-grade. Prior to the placement of the floor slabs, the suitability of the slab subgrades should be determined by proof rolling. A

Capitol Heights, Maryland Findling Project No. 20-1045-06

September 07, 2021 Page 5 of 7 modulus of subgrade reaction of 50 PCI should be used in the design of the floor slab.

The floor slab should be provided with adequate reinforcement, as determined by the Structural Engineer.

In order to provide a relatively uniform subgrade condition and provide protection against water vapor diffusion under the proposed Concrete Pads, it is recommended to undercut about 6 inches of subgrade, placing a vapor barrier and backfill with No. 57 Stone.

Proper curing techniques should be followed in order to reduce the potential development of shrinkage cracks and curling of the slab.

On most projects, there exists a significant lag time between the initial grading and the placement of the floor slab. Environmental conditions and construction traffic often disturb the soil subgrade during this lag time. The contractor should make provisions in the construction specifications for the restoration of the subgrade to a stable condition prior to the placement of the floor slab at no additional cost to the Owner.

8.0 GENERAL GRADING CONSIDERATIONS

8.1 Undercutting

Following the removal of existing pads and excavation to establish the proposed subgrade level, the exposed subgrade should be inspected and tested for adequate support conditions. As discussed previously, undercutting of soft or loose soils may be required in order to establish a suitable bearing surface.

This temporary undercutting should be extended beyond the edge of the proposed pads by a distance equal to at least half the depth of the undercut. The limit of proposed undercutting is shown in Figure 7 in the Appendix.

8.2 Proofrolling

Following removal of topsoil and any soft soils, the subgrade should be thoroughly proof rolled under the observation of a qualified geotechnical engineer. Proofrolling should be performed with a heavily loaded, rubber-tired piece of construction equipment, such as a fully loaded tandem axle dump truck, to detect any soft, loose, or otherwise unstable deposits. Any unsuitable soils should be removed and replaced with structural compacted fill. The approved subgrade should then be scarified, and moisture conditioned to within 3% of soil’s optimum moisture content and re-compacted.

8.3 Fill Selection, Placement, and Compaction

All materials to be used as fill or backfill should be inspected, tested, and approved by the Geotechnical Engineer.

Capitol Heights, Maryland Findling Project No. 20-1045-06

September 07, 2021 Page 6 of 7

On-Site Materials:

The on-site fill materials (from above the water table) that are not excessively wet and those that do not contain any deleterious components can be re-used for the compacted fill in establishing the proposed grades.

Borrow Materials – Select Fill:

The imported fill required should have a unified classification of SP or SM, with less than 10% passing No. 200 sieve.

Fill Compaction:

Compacted structural fill should be placed in approximately horizontal layers, each layer having a loose thickness of not more than 6 inches. All structural fill should be compacted to 95% of the maximum dry density in accordance with ASTM D1557, Modified Proctor. The contractor should select appropriate compaction equipment to achieve the required compaction. Fill placement should commence at the toe of the proposed slopes and progress upwards as additional fill is placed in horizontal lifts.

Field moisture contents of the fill may have to be adjusted in order to obtain suitable degrees of compaction. It is anticipated that field moisture contents of fill materials will need to be controlled to the range of optimum moisture content, plus or minus 3% if stable fills with adequate degrees of compaction are to be obtained.

8.4 Construction Dewatering

At the time of our field investigation, groundwater was encountered in the borings at the depth ranging from 4.5+ feet to 11.5+ feet from the ground surface during the drilling operations and following the completion of the drilling operations. However, depending on the seasonal variations, water may be encountered in shallow excavations, which will require dewatering. Therefore, provisions should be made in the project specifications for dewatering.

8.5 Excavation Considerations

Borings did not encounter any hard strata within the depth of borings at this location.

Therefore, conventional earth moving equipment is anticipated during excavation and backfill operations.

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9.0 ENVIRONMENTAL CONSIDERATIONS

Environmental Investigation for determining if any site-specific health and safety or soil handling requirements that are needed during construction will be addressed in the subsequent report.

10.0 REMARKS

This report has been prepared to aid in the evaluation of the site for the proposed Pads supporting Transformer and Switchgears at Anacostia II, Capitol Heights, MD. It is considered that adequate recommendations have been provided to serve as a basis for the design and preparation of plans and specifications. This report does not contain environmental considerations for the proposed construction. Additional recommendations can be provided as needed.

These analyses and recommendations are based on information made available to us at the time of our investigation and the actual conditions encountered at the test boring locations at that time. General assumptions have been made that the limited exploratory test borings represent the site conditions in relation to the lateral extent and depths of the borings. It should be noted, however, that the actual subsurface conditions between the test boring locations might vary from the conditions indicated on the appended test boring logs. Should the actual conditions encountered during construction differ significantly from those indicated by the test boring logs, we should be notified immediately so that the analyses and recommendations can be reviewed and/or revised as necessary.

APPENDIX

Figure 1: Site Vicinity Map

Figure 2: Project Location Map

Figure 3: Existing Site Condition

Figure 4: Boring Location Plan

Figure 5: Site Geology Map

Figure 6: New Work Plan

Figure 7: Limits of Undercutting

Table 1: Summary of Boring Data

Table 2: Summary of Laboratory Test Results

Grainsize Distribution Curves

Moisture-Density Test Result

CBR Result

Boring Logs

20-1045-06

NOT TO SCALE

DT

SS

1AUGUST 2021

SITE VICINITY MAP

ANACOSTIA II WWPS ELECTRICAL UPGRADE

CAPITOL HEIGHTS, MARYLAND

GWoldetsadik Callout Project Location

GWoldetsadik Oval

DT

SS

2AUGUST 2021

PROJECT LOCATION MAP

ANACOSTIA II WWPS ELECTRICAL UPGRADE

CAPITOL HEIGHTS, MARYLAND

GWoldetsadik Callout Project Location

Polygon

DT

SS

3AUGUST 2021

EXISTING SITE CONDITION

ANACOSTIA II WWPS ELECTRICAL UPGRADE

CAPITOL HEIGHTS, MARYLAND

GWoldetsadik Oval

GWoldetsadik Text Box B-1

GWoldetsadik Oval

GWoldetsadik Text Box B-3

DT

SS

4AUGUST 2021

BORING LOCATION PLAN

CAPITOL HEIGHTS, MARYLAND

DT

SS

5AUGUST 2021

SITE GEOLOGY MAP

ANACOSTIA II WWPS ELECTRICAL UPGRADE

CAPITOL HEIGHTS, MARYLAND

GWoldetsadik Oval

GWoldetsadik Callout Project Location

DT

SS

6AUGUST 2021

DEMOLITION & REPLACEMENT

ANACOSTIA II WWPS ELECTRICAL UPGRADE

CAPITOL HEIGHTS, MARYLAND

GWoldetsadik Oval

GWoldetsadik Text Box B-1

GWoldetsadik Text Box B-3

Oval

DT

SS

7AUGUST 2021

LIMITS OF UNDERCUTTING

CAPITOL HEIGHTS, MARYLAND

Table 1: Summary of Boring Data

Capitol Heights, MD Findling Project No.: 20-1045-06

Boring Ground Number Surface Depth to Bottom

Elevation * Bottom of Fill Depth Elevation

(ft) (ft) (ft) (ft) (ft)

B-1 17.5 13.0 (4.5) 10.0 (7.5) 11.7 (5.8) 11.6 (5.9) 12.0 (5.5) 25.0 -(7.5)

B-3 17.5 6.0 (11.5) 4.5 (13.0) 4.3 (13.2) 2.4 (15.1) 10.4 (7.1) 20.0 -(2.5)

B-4 16.5 5.0 (11.5) 9.0 (7.5) 5.5 (11.0) 5.4 (11.1) 7.7 (8.8) 20.0 -(3.5)

Note:

* Approximated from Google Earth ** Water table elevation could fluctuate due to seasonal conditions NE = Not Encountered NA = Not Applicable

Bottom of BoringFILL

During

Drilling, feet (El) of Drilling

Completion feet (El)

Depth at

24 Hrs

Groundwater Depth, ft **

Cave-in feet (El)feet (El)

Summary of Laboratory Test Results WSSC Anacostia WWPS II Electrical Upgrade

Capitol Heights, MD

Findling Project No.: 20-1045-06

Atterberg Limits

LL PL PI GRAVEL SAND FINES

Bulk 1.0 - 5.0 5.3 19 19 0 32 47 21 131.7 7.9 25.3 SM

S-1 1.0 - 3.0 6.5

S-2 3.5 - 5.5 8.1

S-3 6.0 - 8.0 8.1

S-4 8.5 - 10.5 12.2

S-5 13.5 - 15.0 10.8 NV NP NP 46 47 7 SW-SM

S-6 18.5 - 20.0 17.6

S-7 23.5 - 25.0 22.5

Bulk 1.0 - 5.0 6.3 25 17 8 37 44 19 129.5 8 10.9 SC

S-1 1.0 - 3.0 7.4

S-2 3.5 - 5.5 15.6

S-3 6.0 - 8.0 15.9

S-4 8.5 - 10.5 9.1

S-5 13.5 - 15.0 9.6

S-6 18.5 - 20.0 12.8

S-1 1.0 - 2.5 23.9 61 24 37 2 2 96 CH

S-2 3.5 - 5.0 11.0

S-3 6.0 - 7.5 25.0

S-4 8.5 - 10.0 23.6

S-5 13.5 - 15.0 27.0

S-6 18.5 - 20.0 18.7

B-3

B-4

C B

R V a lu e

S a m p le D e p th

N a tu ra l M o is tu re

C o n te n t, Grain Size Distribution Modified Proctor Compaction Test

(ASTM D1557)

B-1

S a m p le I

D

U S

C S

C la ss ifi ca to in

Max Dry Density, pcf

Optimum Moisture Content, Note: NV = Non Viscous, NP = Non Plastic Page 1 of 1

Colloids LL PL D85 D60 D50 D30 D15 D10 Cc Cu

Material Description USCS AASHTO

Project No. Client: Remarks:

Project:

Source of Sample: B-1 Depth: 1.0'-5.0' Sample Number: Bulk

Date:

Findling, Inc.

Baltimore, Maryland Figure

19 19 8.0165 1.8731 0.5676 0.1933

Light grey, Silty SAND with Gravel SM A-1-b

20-1045-06 Shah & Associates

Anacostia II WWPS Electrical Upgrade

8/16/21

P E

R C

E N

T F

IN

E

R

GRAIN SIZE - mm.

0.0010.010.1110100

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 32.1 7.7 15.2 24.0 21.0 in in in

½ in in

¾ in

½ in

/8 in

Particle Size Distribution Report

Moisture content = 5.3%

Project No. Client: Remarks:

Project:

Source of Sample: B-1 Depth: 13.5'-15.0' Sample Number: S-5

Date:

Findling, Inc.

Baltimore, Maryland Figure

NV NP 11.4188 5.6171 4.0897 1.5053 0.4337 0.2190 1.84 25.64

Light brown, well-graded SAND with Silt and Gravel SW-SM A-1-a

20-1045-06 Shah & Associates

Anacostia II WWPS Electrical Upgrade

8/16/21

P E

R C

E N

T F

IN

E

R

GRAIN SIZE - mm.

0.0010.010.1110100

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 45.6 19.8 19.8 7.8 7.0 in in in

½ in in

¾ in

½ in

/8 in

Moisture content = 10.8%

Project No. Client: Remarks:

Project:

Source of Sample: B-3 Depth: 1.0'-5.0' Sample Number: Bulk

Date:

Findling, Inc.

Baltimore, Maryland Figure

25 17 12.5754 3.7064 0.9436 0.2431

Light brown, Clayey SAND with Gravel SC A-2-4(0)

20-1045-06 Shah & Associates

Anacostia II WWPS Electrical Upgrade

8/16/21

P E

R C

E N

T F

IN

E

R

GRAIN SIZE - mm.

0.0010.010.1110100

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 3.4 33.9 7.5 15.0 21.1 19.1 in in in

½ in in

¾ in

½ in

/8 in

Moisture content = 6.3%

Project No. Client: Remarks:

Project:

Source of Sample: B-4 Depth: 1.0'-2.5' Sample Number: S-1

Date:

Findling, Inc.

Baltimore, Maryland Figure

61 24

Light brown, fat CLAY CH A-7-6(41)

20-1045-06 Shah & Associates

Anacostia II WWPS Electrical Upgrade

8/16/21

P E

R C

E N

T F

IN

E

R

GRAIN SIZE - mm.

0.0010.010.1110100

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 1.5 0.4 0.8 0.5 96.8 in in in

½ in in

¾ in

½ in

/8 in

Moisture content = 23.9%

COMPACTION TEST REPORT

D ry d e n si ty p cf

Water content, %

0 5 10 15 20 25 30

7.9%, 131.7 pcf

Test specification: ASTM D 1557-12 Method A Modified

1.0'-5.0' SM A-1-b 5.3% 19 0 32.1 21.0

Light grey, Silty SAND with Gravel

20-1045-06 Shah & Associates

8/16/21

Elev/ Classification Nat.

Sp.G. LL PI

Depth USCS AASHTO Moist. #4 No.200

TEST RESULTS MATERIAL DESCRIPTION

Project No. Client: Remarks:

Project:

Date:

Source of Sample: B-1 Sample Number: Bulk

Findling, Inc.

Baltimore, Maryland Figure

Maximum dry density = 131.7 pcf

Optimum moisture = 7.9 %

COMPACTION TEST REPORT

D ry d e n si ty p cf

Water content, %

0 5 10 15 20 25 30

8.0%, 129.5 pcf

Test specification: ASTM D 1557-12 Method A Modified

1.0'-5.0' SC A-2-4(0) 6.3% 25 8 37.3 19.1

Light brown, Clayey SAND with Gravel

20-1045-06 Shah & Associates

8/16/21

Elev/ Classification Nat.

Sp.G. LL PI

Depth USCS AASHTO Moist. #4 No.200

TEST RESULTS MATERIAL DESCRIPTION

Project No. Client: Remarks:

Project:

Date:

Source of Sample: B-3 Sample Number: Bulk

Findling, Inc.

Baltimore, Maryland Figure

Maximum dry density = 129.5 pcf

Optimum moisture = 8.0 %

CALIFORNIA BEARING RATIO (CBR) TEST

PROJECT NAME: Anacostia II WWPS Electrical Upgrade PROJECT NO: 20-1045-06 LAB SAMPLE ID: BULK

SAMPLE DESCRIPTION: Light grey, Silty SAND with Gravel BORING NUMBER: B-1

CBR TEST METHOD: ASTM, D1883 (96 Hours Soaked)

MAX. DRY DENSITY (pcf): 131.7 OPT. MOISTURE CONTENT: 7.9% DEPTH, (FT): 1.0'-5.0' (Modified Proctor, D-1557)

TEST-1

DRY DENSITY (pcf): 130.9 MOISTURE CONTENT: 7.7% % SWELL: 0.1%

% COMPACTION OF MODIFIED PROCTOR (T-180): 99.4%

CBR @ 0.1: 37.4 CBR @ 0.2: 40.5

TEST-2

DRY DENSITY (pcf): 115.0 MOISTURE CONTENT: 7.8% % SWELL: 1.3%

% COMPACTION OF MODIFIED PROCTOR (T-180): 87.3%

CBR @ 0.1: 4.0 CBR @ 0.2: 3.8

CBR at 95% Compaction = 25.3

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

85 90 95 100 105

C B

R

Percent Compaction, %

CBR Results

CALIFORNIA BEARING RATIO TEST

SAMPLE DESCRIPTION: Light grey, Silty SAND with Gravel BORING NUMBER: B-1

MAX. DRY DENSITY (pcf): 131.7 OPT. MOISTURE CONTENT: 7.9% DEPTH, (FT): 1.0'-5.0' (Modified Proctor, ASTM D 1557)

DRY DENSITY (pcf): 130.9 MOISTURE CONTENT: 7.7% % SWELL: 0.1%

CBR @ 0.1: 37.4 CBR @ 0.2: 40.5

METHOD: ASTM, D1883 (96 Hours Soaked) % COMPACTION OF MODIFIED PROCTOR (T-180): 99.4%

0.0 0.1 0.2 0.3 0.4 0.5 0.6

P E

N E

T R

A T

IO

N

R E

S

IS

TA

N

C E

P

S I

PENETRATION - INCHES

CBR TEST

SAMPLE DESCRIPTION: Light grey, Silty SAND with Gravel BORING NUMBER: B-1

MAX. DRY DENSITY (pcf): 131.7 OPT. MOISTURE CONTENT: 7.9% DEPTH, (FT): 1.0'-5.0' (Modified Proctor, ASTM D 1557)

DRY DENSITY (pcf): 115.0 MOISTURE CONTENT: 7.8% % SWELL: 1.3%

CBR @ 0.1: 4.0 CBR @ 0.2: 3.8

METHOD: ASTM D1883, 96 Hours Soaked % COMPACTION OF MODIFIED PROCTOR (T-180): 87.3%

0.0 0.1 0.2 0.3 0.4

P E

N E

T R

A T

IO

N

R E

S

IS

TA

N

C E

P

S I

CALIFORNIA BEARING RATIO (CBR) TEST

SAMPLE DESCRIPTION: Light brown, Clayey SAND with Gravel BORING NUMBER: B-3

CBR TEST METHOD: ASTM, D1883 (96 Hours Soaked)

MAX. DRY DENSITY (pcf): 129.5 OPT. MOISTURE CONTENT: 8.0% DEPTH, (FT): 1.0'-5.0' (Modified Proctor, D-1557)

TEST-1

DRY DENSITY (pcf): 132.8 MOISTURE CONTENT: 8.1% % SWELL: 0.0%

% COMPACTION OF MODIFIED PROCTOR (T-180): 102.5%

CBR @ 0.1: 24.3 CBR @ 0.2: 31.6

TEST-2

DRY DENSITY (pcf): 118.5 MOISTURE CONTENT: 8.0% % SWELL: -0.2%

% COMPACTION OF MODIFIED PROCTOR (T-180): 91.5%

CBR @ 0.1: 4.7 CBR @ 0.2: 4.4

CBR at 95% Compaction = 10.9

0.0

5.0

10.0

15.0

20.0

25.0

30.0

85 90 95 100 105

C B

R

Percent Compaction, %

CBR Results

SAMPLE DESCRIPTION: Light brown, Clayey SAND with Gravel BORING NUMBER: B-3

MAX. DRY DENSITY (pcf): 129.5 OPT. MOISTURE CONTENT: 8.0% DEPTH, (FT): 1.0'-5.0' (Modified Proctor, ASTM D 1557)

DRY DENSITY (pcf): 132.8 MOISTURE CONTENT: 8.1% % SWELL: 0.0%

CBR @ 0.1: 24.3 CBR @ 0.2: 31.6

METHOD: ASTM, D1883 (96 Hours Soaked) % COMPACTION OF MODIFIED PROCTOR (T-180): 102.5%

0.0 0.1 0.2 0.3 0.4 0.5 0.6

P E

N E

T R

A T

IO

N

R E

S

IS

TA

N

C E

P

S I

SAMPLE DESCRIPTION: Light brown, Clayey SAND with Gravel BORING NUMBER: B-3

MAX. DRY DENSITY (pcf): 129.5 OPT. MOISTURE CONTENT: 8.0% DEPTH, (FT): 1.0'-5.0' (Modified Proctor, ASTM D 1557)

DRY DENSITY (pcf): 118.5 MOISTURE CONTENT: 8.0% % SWELL: -0.2%

CBR @ 0.1: 4.7 CBR @ 0.2: 4.4

METHOD: ASTM D1883, 96 Hours Soaked % COMPACTION OF MODIFIED PROCTOR (T-180): 91.5%

0.0 0.1 0.2 0.3 0.4

P E

N E

T R

A T

IO

N

R E

S

IS

TA

N

C E

P

S I

NP

0.3 1.0

6.0

10.5

13.0

25.0

6.5

8.1

8.1

12.2

10.8

17.6

22.5

NV

HMA = 4"

Base = 8"

Light brown, dry, dense, Silty SAND (SM); some Gravel;

little Clay; trace Asphalt Fragments, Roots (FILL)

Light brown, moist, loose, SAND (SP); little Silt; trace Gravel, Clay, Woods (Possible Fill)

Brown, moist to wet, medium dense Gravel with Sand;

trace Silt, Clay (Possible

FILL)

Brown, wet, dense to very loose SAND (SW-SM) with Silt; little Gravel; trace Clay

Bottom of Boring @ 25 '

Bulk sample @ 1.0'-5.0'

Coordinates and Elevation are Approximated from Google Earth

Water on Rod @ 10'

Cobble and Gravel @ 11'-13'

6-15-20-17

11-23-21-23

3-5-5-3

5-3-3-2

6-10-13

1-1-1

1-1-2

17.20 16.50

11.50

7.00

4.50

-7.50

1.0- 3.0

3.5- 5.5

6.0- 8.0

8.5- 10.5

13.5- 15.0

18.5- 20.0

23.5- 25.0

11.60 11.60 5.905.90

END

8/12/21

D. Pryor

8/13/21

LB

IN

IN

IN

FT

Driller:

Date Started:

Logged by:

Rig Type

Rig No.

Drive Hammer Weight

Auger Size

Size of Core

Size of Bit OD

Hammer Energy Ratio

Auger Depth 8/12/21

24 hrs.8/13/21

Date Completed:

8/12/21

24 hrs.

Time (hours)

8/13/21

DateTime (hours)Depth (ft)

WATER TABLE

Date Depth (ft)Elev (ft)

Depth Below Surface Depth Below Surface

CAVE-IN TABLE

Elev (ft)

Inspector:

8/12/21

11.70 5.80 12.00 5.50 END

D. Tajhya

D. Tajhya

Truck 45

R-02

3-1/4

LL (%)

SPT SPOON/ROCK CORE

17.5 ft, ' of

3of1Boring

SPT- Standard Penetration Test

1330181.323 454870.814

B-1

REC - Recovery

FINDLING, INC.

BORING LOG

PI - Plasticity Index

LL - Liquid Limit

Legend: NMC - Natural Moisture Content

ELEV.

IN

FEET NMC (%)

20-1045-06

0-

-0

S H

A H

A

S S

O C

IA

T

E S

W S

S C

A N

A C

O S

T

IA

W W

P S

II

E

LE

C

T R

IC

A

L U

P G

R A

D E

.G P

J- 8/

/2

Project Description:

REC.

SPT(in) or Core (%)

Boring No.

M

A T

L

RQD - Rock Quality Designation Elev - Elevation

MATL- Material Graphics

Geotech - Geotechnical OD - Outside Diameter

BLOWS/

RQD

SAMPLE

NO.

Station:

Easting:

REMARKSSAMPLE

DEPTH PI (%)

Sheet 1 1

Boring and Sampling Conforms to ASTM/AASHTO:

LAB. INDEX TESTSDEPTH

IN

FEET

MATERIAL DESCRIPTION

Northing:

Project No.:

Ground Surface Elevation:

WSSC Anacostia II WWPS Electrical Upgrade

0.3 1.1

3.0

6.0

8.0

18.0

20.0

7.4

15.6

15.9

9.1

9.6

12.8

HMA = 4"

Base = 9"

Brown, dry, medium dense, Clayey SAND (SC) with Gravel; trace Roots (FILL)

Light brown, moist, loose SAND (SP); some Silt; trace Gravel, Roots (Possible FILL)

Brown, wet, medium dense, Silty SAND (SM); trace Clay

Brown, wet, medium dense SAND (SP); little Silt, Gravel

Brown, wet, dense SAND (SP) with Gravel; trace Silt

Bottom of Boring @ 20 '

Bulk sample @ 1.0'-5.0'

Coordinates and Elevation are Approximated from Google Earth Water on Rod @ 4.5'

Water poured in auger starting from S-5

7-12-10-7

3-3-4-4

5-7-8-15

8-13-10-6

4-8-10

7-8-18

17.20 16.40

14.50

11.50

9.50

-0.50

-2.50

1.0- 3.0

3.5- 5.5

6.0- 8.0

8.5- 10.5

13.5- 15.0

18.5- 20.0

2.40 4.30 13.2015.10

END

8/12/21

D. Pryor

8/13/21

LB

IN

IN

IN

FT

Driller:

Date Started:

Logged by:

Rig Type

Rig No.

Drive Hammer Weight

Auger Size

Size of Core

Size of Bit OD

Hammer Energy Ratio

Auger Depth 8/12/21

24 hrs.8/13/21

Date Completed:

8/12/21

24 hrs.

Time (hours)

8/13/21

DateTime (hours)Depth (ft)

WATER TABLE

Date Depth (ft)Elev (ft)

Depth Below Surface Depth Below Surface

CAVE-IN TABLE

Elev (ft)

Inspector:

8/12/21

4.30 13.20 10.40 7.10 END

D. Tajhya

D. Tajhya

Truck 45

R-02

3-1/4

LL (%)

SPT SPOON/ROCK CORE

17.5 ft, ' of

3of2Boring

SPT- Standard Penetration Test

1330197.763 454766.857

B-3

REC - Recovery

FINDLING, INC.

BORING LOG

PI - Plasticity Index

LL - Liquid Limit

Legend: NMC - Natural Moisture Content

ELEV.

IN

FEET NMC (%)

20-1045-06

0-

-0

S H

A H

A

S S

O C

IA

T

E S

W S

S C

A N

A C

O S

T

IA

W W

P S

II

E

LE

C

T R

IC

A

L U

P G

R A

D E

.G P

J- 8/

/2

Project Description:

REC.

SPT(in) or Core (%)

Boring No.

M

A T

L

RQD - Rock Quality Designation Elev - Elevation

MATL- Material Graphics

Geotech - Geotechnical OD - Outside Diameter

BLOWS/

RQD

SAMPLE

NO.

Station:

Easting:

REMARKSSAMPLE

DEPTH PI (%)

Sheet 1 1

Boring and Sampling Conforms to ASTM/AASHTO:

LAB. INDEX TESTSDEPTH

IN

FEET

MATERIAL DESCRIPTION

Northing:

Project No.:

0.4 1.3

3.5

5.0

7.5

10.0

20.0

23.9

11.0

25.0

23.6

27.0

18.7

HMA = 5"

Base = 9"

Light brown, moist, medium stiff, high plasticity CLAY (CH); trace Silt (Possible

FILL)

Brown, moist, medium dense SAND (SP) with Gravel; trace Clay (Possible FILL)

Brown, moist, loose SAND (SP); trace Silt

Brown, grey, wet, loose, Silty

SAND (SM)

Light brown, wet, loose SAND (SP); trace Gravel

Bottom of Boring @ 20 '

Bulk sample @ 1.0'-5.0'

Coordinates and Elevation are Approximated from Google Earth

Water on Rod @ 9'

Water poured in auger starting from S-5

9-5-3

5-8-4

3-3-4

1-2-4

2-3-6

1-2-3

16.10 15.20

13.00

11.50

9.00

6.50

-3.50

1.0- 2.5

3.5- 5.0

6.0- 7.5

8.5- 10.0

13.5- 15.0

18.5- 20.0

5.40 6.00 10.5011.10

END

8/12/21

D. Pryor

8/13/21

LB

IN

IN

IN

FT

Driller:

Date Started:

Logged by:

Rig Type

Rig No.

Drive Hammer Weight

Auger Size

Size of Core

Size of Bit OD

Hammer Energy Ratio

Auger Depth 8/12/21

24 hrs.8/13/21

Date Completed:

8/12/21

24 hrs.

Time (hours)

8/13/21

DateTime (hours)Depth (ft)

WATER TABLE

Date Depth (ft)Elev (ft)

Depth Below Surface Depth Below Surface

CAVE-IN TABLE

Elev (ft)

Inspector:

8/12/21

5.50 11.00 7.70 8.80 END

D. Tajhya

D. Tajhya

Truck 45

R-02

3-1/4

LL (%)

SPT SPOON/ROCK CORE

16.5 ft, ' of

3of3Boring

SPT- Standard Penetration Test

1330177.29 454715.436

B-4

REC - Recovery

FINDLING, INC.

BORING LOG

PI - Plasticity Index

LL - Liquid Limit

Legend: NMC - Natural Moisture Content

ELEV.

IN

FEET NMC (%)

20-1045-06

0-

-0

S H

A H

A

S S

O C

IA

T

E S

W S

S C

A N

A C

O S

T

IA

W W

P S

II

E

LE

C

T R

IC

A

L U

P G

R A

D E

.G P

J- 8/

/2

Project Description:

REC.

SPT(in) or Core (%)

Boring No.

M

A T

L

RQD - Rock Quality Designation Elev - Elevation

MATL- Material Graphics

Geotech - Geotechnical OD - Outside Diameter

BLOWS/

RQD

SAMPLE

NO.

Station:

Easting:

REMARKSSAMPLE

DEPTH PI (%)

Sheet 1 1

Boring and Sampling Conforms to ASTM/AASHTO:

LAB. INDEX TESTSDEPTH

IN

FEET

MATERIAL DESCRIPTION

Northing:

Project No.:

(Blank Page -- End of Report)