Amendment 01 - Appendix E UPDATED Geotechnical Design Report and Analyses.pdf

SPRING CREEK NORTH

ECOSYSTEM RESTORATION PROJECT

BROOKLYN & QUEENS, NEW YORK

DESIGN DOCUMENTATION REPORT

APPENDIX E – GEOTECHNICAL DESIGN REPORT AND ANALYSES

PREPARED FOR:

U.S. ARMY CORPS OF ENGINEERS

NEW YORK DISTRICT

and

NEW YORK CITY PARKS

PREPARED BY:

PRINCETON HYDRO, LLC.

100% DESIGN – NOVEMBER 2023

SPRING CREEK NORTH

SUBSURFACE INVESTIGATION

BROOKLYN/QUEENS, KINGS/QUEENS COUNTY, NY

NOVEMBER 2023

PREPARED FOR:

U.S. ARMY CORPS OF ENGINEERS

NEW YORK DISTRICT;

NEW JERSEY DEPARTMENT OF

ENVIRONMENTAL PROTECTION

PREPARED BY:

PRINCETON HYDRO, LLC

1200 LIBERTY PLACE

SICKLERVILLE, NJ 08081

856-629-8889

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TABLE OF CONTENTS

1. Introduction

2. Document Review

2.1 Surficial Geology

2.2 Bedrock Geology

3. Field Investigation

3.1 Introduction

3.2 Phase I/Phase II

3.2.1 Geotechnical Borings

4. Laboratory Testing

4.1 Laboratory Testing – Geotechnical Borings

5. Subsurface Conditions

5.1 Introduction

6. Geotechnical Analysis

6.1 Slope Stability Analysis

6.1.1 Model Development

6.1.2 Methodology

6.1.3 Stability Results

7. Recommendations

7.1 Initial Site Clearing, Excavation, Grading, and Earthwork

7.2 Proof Rolling

7.3 Subgrade Guidance

7.4 Dewatering

7.6 Excavation Safety

8. Quality Control

9. Limitations

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Appendices Appendix A: Field Testing Location Map Appendix B: Field Logs Appendix C: Laboratory Testing Results Appendix D: Slope Stability Analysis

PRIMARY AUTHOR

Matthew Pappas

CONTRIBUTING AUTHOR(S)

Casey J. Pantaleo, P.E.

Marissa Ciocco, EIT

Spring Creek North Geotechnical Sampling and Analysis

Brooklyn/Queens, Kings/Queens County, NY 100% Design- November 2023

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1. INTRODUCTION

Princeton Hydro was contracted by the United States Army Corps of Engineers (USACE) to perform a geotechnical evaluation in support of the proposed ecosystem restoration project at Spring Creek North located in the boroughs of Brooklyn and Queens, New York. The area under investigation is bound to the north by Flatlands Avenue, to the east by 77th Street, and to the west by the New York City Department of Environmental Protection (NYCDEP) 26th Ward Water Pollution Control Plant. The site has been identified as Spring Creek “North” to prevent confusion with the adjacent “Spring Creek South” project on the eastern side of the Belt Parkway. The Project would restore approximately 43.2 acres of degraded habitat to 0.7 acres of low marsh, 12.9 acres of transitional and high marsh, 5.2 acres of scrub shrub wetland, 11.3 acres of maritime grassland, 3.4 acres of maritime scrub shrub upland, and 9.7 acres of maritime forest.

Primary construction activities involve excavating and re-contouring uplands to intertidal elevations, removing invasive plant species, and replanting with native plant species. The overall project purpose is to improve the environmental quality (water diversity and wildlife habitat) of Spring Creek and its associated salt marshes as part of the overall Jamaica Bay Ecosystem.

As part of the geotechnical engineering portion of this project, Princeton Hydro was tasked with the following items:

1. A geotechnical evaluation consisting of:

a. Eleven (11) standard geotechnical borings

b. Laboratory testing consisting of soil index tests (i.e., grain size analysis, unit weight, specific gravity, Atterberg Limits, etc.), California Bearing Ratio testing, soil classifications, one-dimensional consolidation testing, and triaxial shear testing; and

2. Drafting of a geotechnical memorandum/report to summarize the subsurface findings and interpret results for design and construction purposes.

This report presents and summarizes the document review and subsurface investigations in support of this ecosystem restoration project.

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2. DOCUMENT REVIEW

Prior to initiation of field activities, Princeton Hydro performed a comprehensive review of mapped surficial and geological deposits within Spring Creek North. The following subsections outline the findings of this review:

2.1 SURFICIAL GEOLOGY

The site is located within the Coastal Plain Physiographic Province of New York. The Coastal Plain has relatively flat, thick, sandy soils that allow rapid infiltration of rainfall. The Coastal Plain Province is underlain by a wedge of unconsolidated sediments that form permeable units (aquifers) of sand and gravel interbedded with poorly permeable (confining) units of silt and clay. These interbedded, unconsolidated sediments differ in thickness and areal extent, but generally dip and thicken southeastward to a maximum thickness of about 6,500 feet at the coast. Glacial deposits overlie most of Long Island and form the unconfined (water-table) aquifer and local water-bearing deposits of lesser extent. These systems are underlain by the Magothy and Lloyd aquifers, which are generally confined.1

Surficial geology of the Lower Hudson region of NY State, provided by the New York State Museum, identifies the project site to consist primarily of the following:

Outwash Sand and Gravel: coarse to fine grained with sand, proglacial fluvial deposition, well rounded and stratified, generally fine texture away from ice border with variable thickness (2-20meters).2

2.2 BEDROCK GEOLOGY

Bedrock mapping reveals that the bedrock formation directly underlying the site is the Monmouth Group, Matawan Group and Magothy Formation3.

Monmouth Group, Matawan Group and Magothy Formation (Km):

The major lithologic constituents consist of unconsolidated coarse-detrital gravel, unconsolidated fine-detrital clay (silty clay, glauconitic sandy clay), unconsolidated coarse-detrital sand (sandy clay, sand) and the minor lithologic constituents consist of unconsolidated fine-detrital silt (silty clay).

3. FIELD INVESTIGATION

3.1 INTRODUCTION

The total field investigation performed by Princeton Hydro for Spring Creek North consisted of the advancement of eleven (11) geotechnical test borings. A field-testing location map is included in Appendix A – Field Testing Location Map.

The shallower 20-25-foot borings in the tidal wetland – upland area were proposed with the intent to help develop an understanding of the materials being excavated for the restoration and to facilitate in slope stability analysis.

1 Paul E. Stackelberg and Mark A. Ayers. “USGS Fact Sheet 1994–0012: Long Island-New Jersey (LINJ) Coastal Drainages Study.” USGS Publications Warehouse, https://pubs.usgs.gov/fs/1994/0012/.

2 “Lower Hudson.” Geographic Information System (GIS) | The New York State Museum, http://www.nysm.nysed.gov/research-collections/geology/gis.

3 Fisher, D.W., Isachsen, Y.W., and Rickard, L.V., 1970, Geologic Map of New York State, consisting of 5 sheets: Niagara, Finger Lakes, Hudson- Mohawk, Adirondack, and Lower Hudson, New York State Museum and Science Service, Map and Chart Series No. 15, scale 1:250,000.

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The remaining borings progressed in the maritime upland areas were advanced to 50 feet below ground surface due to the presence of thick layers of asphalt, which was estimated to be approximately 3 feet thick in some areas. As the paved areas are expected to receive a significant amount of fill from the other areas of the site, the increased boring exploration depth was required to ascertain the true thickness of the pavement as well as identify the underlying soil strata to facilitate with settlement analyses for the restoration project.

The geotechnical investigation was split into two phases due to access restrictions only discovered during the initial site visit to advance borings. The established trees, which were not permitted to be removed, and the existing perimeter chain-link fence surrounding the auxiliary wastewater treatment plant prevented access to the peninsula located southeast of the treatment plant during the first site visit. Therefore, the field crews returned to the site two months later, for “Phase II”, to temporarily remove a section of the perimeter fence to access the peninsula and advance borings B-5 and B-11 as identified on the field testing location map. Upon the completion of the borings, the chain-link fence was restored to its original condition as best as possible, with the knowledge that the fence will eventually be fully removed as part of construction for the restoration project.

As part of each phase of the field investigation, a Princeton Hydro engineer was on site to field locate each testing location, approximating the locations called out on the 30% plans with the aid of Maprika software in place of a handheld GPS unit.

3.2 PHASE I/PHASE II

3.2.1 GEOTECHNICAL BORINGS

From January 10th through January 13th, 2020, Princeton Hydro observed the advancement of nine (9) geotechnical borings by way of a CME-55LCX tracked drill rig, owned and operated by Boring Brothers, Inc. These borings were located throughout the site, with the exception of the peninsula located southeast of the treatment plant as stated above. Four (4) of the Phase I borings were advanced to 27.0 feet below the existing ground surface. These included borings located East of Spring Creek, Area B, (borings B-1, B-2, and B-3), and immediately West of Spring Creek, Area A, above the peninsula (boring B-4). The remaining five borings in Phase I (B-6, B-7, B- 8, B-9, and B-10), located in the paved Areas E, F, and G, were advanced to 52.0 feet below the existing ground surface. Borings B-1 through B-4 were advanced utilizing mud rotary drilling methodology. For Borings B-6 through B-10, due to the presence of a three-foot-thick layer of asphalt, coring methodology was utilized to reach native soils and then standard mud rotary methods were used to complete the test borings.

On March 16th, Princeton Hydro returned to the site with the intent to observe the advancement of four (4) additional geotechnical borings by way of CME-55LCX tracked drill rig, owned and operated by Boring Brothers, Inc. As part of the field effort to reach the locations of the remaining borings, the perimeter fence from the auxiliary wastewater treatment plant needed to be temporarily removed from the posts to allow for access to the boring locations. As a result of complications with access, restrictions on clearing, and dense surface materials only two (2) of the intended borings were advanced. Borings B-5 and B-11, as depicted in Appendix A – Field Testing Location Map. Both were advanced to 22.0 feet below the existing ground surface. Based on field observations and the proximity of the two “missed” locations, it was determined that a third site visit (a Phase III) was not warranted. Upon completion of the Phase II field effort, the sections of removed fence were restored to as close to their original condition as possible without replacement of the sections, at the agreement of all parties involved.

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Split-spoon sampling (in accordance with ASTM D1586) was completed continuously for the first ten (10) to twelve

(12) feet (depending on if a Shelby Tube was taken), and then at five (5) foot intervals thereafter. An undisturbed tube sample was collected at boring B-1 in accordance with ASTM D1587.

The performance of the field work and classifications/sampling of recovered material was observed and documented by a Princeton Hydro geotechnical engineer. Boring locations are illustrated on the Field Testing Location Map provided in Appendix A – Field Testing Location Map. Detailed boring logs can be found in Appendix B – Field Logs.

All borings in Phase I and Phase II were advanced to their intended depths, without terminating early due to refusal. Upon completion, the borings were backfilled with soil cuttings and the top 1-foot of the boreholes were filled with bentonite chips to meet existing grades. The borings in paved areas also received an asphalt cold patch of 6 inches.

4. LABORATORY TESTING

Upon completion of the field investigation, Princeton Hydro secured the services of TerraSense, LLC to perform laboratory testing on select soil samples. The following sections outline the results of the laboratory testing.

4.1 LABORATORY TESTING – GEOTECHNICAL BORINGS

Following completion of each phase of the field evaluation, testing on select soil samples representative of the stratigraphy observed at the site was performed. The samples were tested in accordance with the testing methodologies presented in Table 4 - 1 below.

Table 4 - 1: ASTM Standard Tests Performed

Standard Description

ASTM D2216 Standard Test Methods for Water (Moisture) of Soils

ASTM D6913 Standard Test Method for Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis

ASTM D1140 Standard Test Methods for Determining the Amount of Material Finer than 75 µm (No.

200) Sieve in Soils by Washing

ASTM D4318 Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils

ASTM D2487 Standard Practice for Classification of Soils for Engineering Purposes (Unified Classification System)

ASTM D2435 Standard Test Methods for One-Dimensional Consolidation Properties of Soils Using Incremental Loading

The field investigation, sampling, and laboratory testing have provided pertinent classification information utilized to assign and/or correlate engineering parameters to the underlying site soils. Laboratory testing results are summarized in Table 4 - 2 through Table 4 - 2 below. Data sheets and test specific information are provided in Appendix C – Laboratory Testing Results. No lab testing was performed on recovered soils from the Phase II field investigation.

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Table 4 - 2: Laboratory Test Results - Geotechnical Borings (Phase I)

Location B-1 B-1 B-2 B-2 Sample S-7 S-9 S-4+S-5 S-8

Depth (ft) 12-14 20-22 6-10 20-22

ASTM D2216

Moisture Content (%) 73.5 20.3 22.0 23.2

ASTM C136/D1140

Gravel (%) 0 0 32 0.7

Sand (%) 55 95.8 47 96.3

Fines (%) 45 4.2 21 3

ASTM D4318 (NT = Not Tested, NP = Non Plastic)

Plastic Limit 43 19 26 19

Liquid Limit 124 - 39 -

Plasticity Index 81 NP 13 NP

ASTM D2487

USCS Symbol SC SP SM SP

USCS Description Clayey Sand Poorly Graded Sand

Silty Sand with Gravel

Poorly Graded Sand

Table 4 - 3: Laboratory Test Results - Geotechnical Borings (Phase I)

Location B-3 B-3 B-3 B-4 Sample S-5 S-7 S-9 S-7+S-8

Depth (ft) 8-10 15-17 20-22 15-22

ASTM D2216

Moisture Content (%) 10.6 26.5 21.4 180.5

ASTM C136/D1140

Gravel (%) 54 0.4 0.3 3

Sand (%) 37 97.2 96.8 66

Fines (%) 9 2.4 2.9 31

ASTM D4318 (NT = Not Tested, NP = Non Plastic)

Plastic Limit 19 20 16 110

Liquid Limit 21 - - 242

Plasticity Index 2 NP NP 132

ASTM D2487

USCS Symbol GP-GM SP SP SM

USCS Description Poorly Graded Gravel with Silt and Sand

Poorly Graded Sand

Poorly Graded Sand Silty Sand

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Table 4 - 4: Laboratory Test Results - Geotechnical Borings (Phase I)

Location B-4 B-6 B-6 B-6 Sample S-9 S-5 S-7 S-13

Depth (ft) 25-27 8-10 15-17 45-47

ASTM D2216

Moisture Content (%) 23.2 22.6 27.3 22.1

ASTM C136/D1140

Gravel (%) 1 5 0 2

Sand (%) 95 83 95 95

Fines (%) 4 12 5 3

ASTM D4318 (NT = Not Tested, NP = Non Plastic)

Plastic Limit 20 25 23 17

Liquid Limit - - - -

Plasticity Index NP NP NP NP

ASTM D2487

USCS Symbol SP SP-SM SP-SM SP

USCS Description Poorly Graded Sand

Poorly Graded Sand with Silt

Poorly Graded Sand with Silt

Poorly Graded Sand

Table 4 - 5: Laboratory Test Results - Geotechnical Borings (Phase I)

Location B-7 B-7 B-7 B-8 Sample S-7 S-10 S-13 S-6

Depth (ft) 15-17 30-32 45-47 10-12

ASTM D2216

Moisture Content (%) 34.0 24.9 23.3 44.7

ASTM C136/D1140

Gravel (%) 0 2 0 26

Sand (%) 96.4 94 95.2 62

Fines (%) 3.6 4 4.8 12

ASTM D4318 (NT = Not Tested, NP = Non Plastic)

Plastic Limit 23 22 23 48

Liquid Limit - - - -

Plasticity Index NP NP NP NP

ASTM D2487

USCS Symbol SP SP SP SP-SM

USCS Description Poorly Graded Sand

Poorly Graded Sand

Poorly Graded Sand

Poorly Graded Sand with Silt and

Gravel

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Table 4 - 6: Laboratory Test Results - Geotechnical Borings (Phase I)

Location B-8 B-8 B-9 B-9 Sample S-10 S-14 S-3 S-10

Depth (ft) 30-32 50-52 4-6 30-32

ASTM D2216

Moisture Content (%) 23.3 31.1 30.6 19.6

ASTM C136/D1140

Gravel (%) 0.1 0 13 5

Sand (%) 95.9 69.5 74 90

Fines (%) 4 30.5 13 5

ASTM D4318 (NT = Not Tested, NP = Non Plastic)

Plastic Limit 18 25 44 18

Liquid Limit - 25 48 -

Plasticity Index NP NP 4 NP

ASTM D2487

USCS Symbol SP SM SM SP-SM

USCS Description Poorly Graded Sand Silty Sand Silty Sand Poorly Graded

Sand with Silt

Table 4 - 7: Laboratory Test Results - Geotechnical Borings (Phase I)

Location B-9 B-10 B-10 B-10 Sample S-13 S-8+S-9 S-12 S-13

Depth (ft) 45-47 20-27 40-42 45-47

ASTM D2216

Moisture Content (%) 18.0 18.1 25.3 20.3

ASTM C136/D1140

Gravel (%) 10 4 0 0.2

Sand (%) 84 90 93.9 95.9

Fines (%) 6 6 6.1 3.9

ASTM D4318 (NT = Not Tested, NP = Non Plastic)

Plastic Limit 22 19 22 18

Liquid Limit - - - -

Plasticity Index NP NP NP NP

ASTM D2487

USCS Symbol SP-SM SP-SM SP-SM SP

USCS Description Poorly Graded Sand with Silt

Poorly Graded Sand with Silt

Poorly Graded Sand with Silt

Poorly Graded Sand

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5. SUBSURFACE CONDITIONS

5.1 INTRODUCTION

The subsurface profile within Spring Creek North consists of a layering of anthropogenic (man-made) and native materials. The soils encountered in the soil borings have been generalized from the subsurface investigations performed for ease of discussion based on morphology, color, consistency, strength, and other relevant soil characteristics. These descriptions are presented in Table 5 - 1 (below) with Unified Soil Classification System (USCS) descriptions. Additionally, observed depths to groundwater are presented below in Table 5-2. Note that the groundwater levels will seasonally fluctuate due to variations in the amount of precipitation, evaporation, and surface water runoff. The boring logs utilized in the creation of the subsurface conditions can be found within Appendix B – Field Logs.

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Table 5 - 1: Generalized Subsurface Profile – Spring Creek North

Stratum Description

Asphalt

Asphalt: black to dark gray to dark brown, well graded to poorly graded fine to coarse gravels, very gravelly poorly graded sand, and slightly silty fine sand (GP, GW, SP, SM), moist, medium dense to very dense.

Asphalt was present at borings B-6, B-7, B-8, B-9, and B-10. This stratum was observed to range from 1 to 4 ft in thickness and was observed from depths between 0 to 4 fbgs.

IF

Fill: dark brown to black to dark gray to light gray to white, silty sand (topsoil) medium poorly graded sand, well graded fine to coarse gravel, lean clay, fat clay, well graded fine to medium sand with silt, clayey sand, and poorly graded medium gravel (SM, SP, GW, CL, CH, SW-SM, SC, GP), moist, loose to dense and very soft to very stiff.

Fill was present in all boring locations. The Stratum IF ranged in thickness from 2-22 ft and was observed between depths 0-22 fbgs.

II

Poorly Graded Gravel/Silty Gravel: light to dark gray to black, poorly graded fine to coarse gravel with silt and sand (GP, GP-GM), moist to wet, medium dense.

Stratum II was encountered directly under the Fill (Stratum IF) in both Borings B-1 and B-3. Stratum II was also encountered in Boring B-10 where it was nested within Stratum V at 32.0 fgbs.

Stratum II was present in borings B-1, B-3, and B-10. The stratum ranged in thickness from 4-5ft and was observed at depths between 4-11 fbgs and between 32-37 fbgs.

III

Clayey/Silty Sand: light gray to gray to dark gray to dark brown to black, slightly gravelly to extremely gravelly clayey sand, silty sand with little fine to medium gravels, (SC, SM), moist to wet, very loose to dense.

Stratum III was encountered directly under Stratum IF in Borings: B-2, B-3, B-6, B-7, B-8, B-9 and B-10.

Stratum III was encountered directly beneath Stratum II and was bisected by Stratum IV in Boring B-

1. Stratum III was also bisected by Stratum V in Boring B-8.

Stratum III was present in borings B-1, B-2, B-6, B-7, B-8, B-9, and B-10. The stratum ranged in thickness from 1-25ft and was observed at depths between 4-52 fbgs.

IV

Peat/Fat Clay: Dark gray to gray peat with some clayey sand and lean clay intermixed throughout with organic matter and a slight organic odor present to fat clay with trace to little organics noted (PT, CH), moist to wet, very soft to medium.

Stratum IV was encountered bisecting Stratum III in Boring B-1, directly beneath Stratum IF in Borings B-2 and B-5, and directly beneath Stratum II in Boring B-3.

Stratum IV was present in borings B-1, B-2, B-3, and B-5. The stratum ranged in thickness from 2-9 ft and was observed at depths between 7-16 fbgs.

V

Poorly Graded/Well Graded Sand: Light gray to gray to olive gray to grayish brown to olive brown to dark reddish brown to brown, well graded very fine to medium sand with trace to little fine to coarse gravels, silt and shell fragments noted to poorly graded fine to medium sand with trace clay noted (SW, SP), wet, very loose to dense.

Stratum V was encountered directly beneath Stratum IF in Boring B-4, directly beneath Stratum II in Boring B-5, directly beneath Stratum III in Borings B-1, B-2, B-6, B-7, B-8, and B-10 (Stratum V in Boring B-10 was bisected by Stratum II), and directly beneath Stratum IV in Borings B-2 and B-3.

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Stratum Description

Stratum V was present in borings B-1, B-2, B-3, B-4, B-5, B-6, B-7, B-8, and B-10. The stratum ranged in thickness from 2-47 ft and was observed at depths between 5-52 fbgs.

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Table 5 - 2: Spring Creek North Observed Depths to Groundwater Summary

Boring Location Surface

Elevation of Boring (ft)*

Depth to Groundwater

(ft)

Elevation of Groundwater

(ft)

B-1 10.0 6.0 4.0

B-2 10.0 6.0 4.0

B-3 10.0 6.0 4.0

B-4 15.0 8.0 7.0

B-5 8.5 9.5 -1.0

B-6 10.7 5.0 5.7

B-7 10.5 6.5 4.0

B-8 11.5 5.0 6.5

B-9 13.6 6.0 7.6

B-10 16.0 6.0 10.0

B-11 9.5 6.3 6.2

*Elevations obtained from site survey, referenced to NAVD88

Based on the information obtained during the investigations performed, the following soil design parameters in Table 5 - 3 were determined for use across the site:

Table 5 - 3 Spring Creek North Soil Design Parameters

Soil Parameter Asphalt Stratum IF (Fill)

Stratum II (Gravel)

Stratum III (Silty Sand)

Stratum IV (Peat)

Stratum V (Sand)

Moist Unit weight1, (pcf) 145 115 130 120 72 130

Friction Angle2, (degrees) 45 32 34 30 - 30

Cohesion3, c (psf) - - - - 375 - 1Coduto, 2001; 2Peck et al, 1974; 3Das, 1994, 4ASTM D7012, 5Hoek et al, 2002

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6. GEOTECHNICAL ANALYSIS

6.1 SLOPE STABILITY ANALYSIS

A slope stability analysis was conducted at the two proposed transition areas from the upland to the wetland areas and at the three proposed upland placement areas. These areas were modeled based on subsurface information obtained from geotechnical borings as well as the proposed topography.

6.1.1 MODEL DEVELOPMENT

Five (5) cross sections through the proposed restoration features were developed utilizing the proposed Project Area topography (Figure 6 - 1 and Figure 6 - 2). The cross section locations were selected to intersect the most critical, or steepest, portion of the slope at major segments of the cutdown transition between the upland to wetland project areas or proposed material placement at the upland placement areas. Each cross section was developed utilizing the following primary assumptions:

1. Subsurface soil and elevations were modeled based on the boring located at each location; B-11 (Cross Section 1), B-1 (Cross Section 2), B-10 (Cross Section 3), B-9 (Cross Section 4), and B-6 and B-7 (Cross Section 5);

2. The top 1 ft of the proposed slope topography will be comprised of clean cap material. This material was assumed to consist of a well-graded sand with a unit weight of 115 pounds per cubic foot and a friction angle of 33 degrees; and

3. The soil properties of the cross sections are based upon the values presented in Table 5-3 of this report;

4. It is assumed that material to create the Upland Placement Areas will be excavated from two excavation areas consisting of sandy material. A homogenized material was utilized in the slope stability analysis by assuming a compacted excavation fill material unit weight of 144 pounds per cubic foot and friction angle of 33 degrees. This material was utilized in Cross Sections 3, 4, and 5.

It should be noted that while the geotechnical borings provide valuable information for identifying subsurface materials, they cannot accurately predict the subsurface conditions along the entirety of their respective cross section. Boring stratum observations are utilized along the length of the cross section for modeling purposes.

Detailed cross sections can be found in Appendix D of this report. Please note that this analysis represents the fully constructed slopes as they are currently proposed. It does not take any interim grading or staged construction into account.

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Figure 6 - 1: Proposed Topography and Cross Sections for Upland to Wetland Transition

Cross Section 1

Cross Section 2

Cross Section 4

Cross Section 3

Cross Section 5

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Figure 6 - 2: Proposed Topography and Cross Sections for Upland Placement Areas

6.1.2 METHODOLOGY

Slide2 Software Application Overview:

The stability analysis was performed utilizing the Slide2 slope stability software, developed by Rocscience. This commercially available software allows the user to define the slope limits to be analyzed. These are represented by the gray horizontal arrows noted on the graphical output provided within the software analyses reports.

Therefore, failure surfaces are confined within these extents. For each cross section, analyses were performed to evaluate both circular and non-circular failure surfaces at the end of the construction. A seismic analysis was also performed for each cross section. For reference, a sample of the slope geometry utilized for the search method is presented in *The water table (“W”) at Cross Section 1 is recorded at 4.0 fbgs.

Figure 6 - 4 to *The water table(“W”) at Cross Section 4 is recorded at 5.7 fbgs.

Figure 6 - 9. The keys for each stratum, including color and parameters are shown below. Additionally, the blue “W” in each figure represents the water table at that location based on the boring logs that were collected.

Figure 6 - 3: Key for Cross Section 1 and 2

*The water table (“W”) at Cross Section 1 is recorded at 4.0 fbgs.

Figure 6 - 4: Sample Slope Geometry - Cross Section 1

*The water table (“W”) at Cross Section 2 is recorded at 4.0 fbgs.

Figure 6 – 5: Sample Slope Geometry – Cross Section 2

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Figure 6 – 6: Key for Cross Section 3, 4, and 5

*The water table(“W”) at Cross Section 3 is recorded at 10.0 fbgs.

Figure 6 - 7: Sample Slope Geometry - Cross Section 3

*The water table(“W”) at Cross Section 4 is recorded at 7.6 fbgs.

Figure 6 - 8: Sample Slope Geometry - Cross Section 4

*The water table(“W”) at Cross Section 4 is recorded at 5.7 fbgs.

Figure 6 - 9: Sample Slope Geometry - Cross Section 5

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Methodology:

The analysis was completed in general accordance with Engineer Manual (EM) 1110-2-1902 titled “Slope Stability,” dated October 31, 2003. Each cross section was analyzed for circular and non-circular failures utilizing Spencer’s Method (force and moment equilibrium) for the left-to-right failure direction for Cross Section 1 and 2, and the left-to-right and right-to-left failure directions for Cross Sections 3, 4, and 5. Specifically, this analysis looks at the end-of-construction condition and seismic loading (Pseudo-static) condition.

The pseudo-static seismic analysis utilizes a horizontal seismic coefficient of 0.085. It is understood that USACE is currently developing a new EM to address seismic analysis, however this material was not available at the time of this analysis. As recommended by Hynes-Griffin and Franklin, the seismic coefficient can be calculated as 0.5*PGA (peak ground acceleration). A PGA value of 0.17 for Risk Category I, Soil Class D – Stiff Soil at the Project Area was determined from the ASCE7 Hazard tool. Output from the ASCE7 Hazard tool is located in Appendix D.

As presented in the April 1970 version of EM 1110-2-1902, a horizontal seismic coefficient of 0.085 corresponds to a moderate to major level of damage within the continental United States. For additional context, the report titled “Seismic Coefficients for Pseudo-static Slope Analysis,” dated August 2004, by Melo and Sharma was reviewed. The report summarized horizontal seismic coefficients recommended by the following sources: United States, Japan, Terzaghi, Seed, Corps of Engineers, Marcuson, and Hynes-Griffin. This source confirms that a Horizontal Seismic Coefficient of 0.085 is acceptable for use within the United States. The selected value is associated with an event considered just less than a “severe earthquake.” For further context, maximum values given by Terzaghi for “catastrophic” earthquakes, are on the order of 0.5.

Groundwater Modeling:

Groundwater was modeled at the groundwater elevation observed during the performance of the test borings.

This was assumed to extend across each model at a consistent elevation. Specifically, the groundwater elevations utilized for each model are:

Cross Section 1 – Elevation 3.2 ft Cross Section 2 – Elevation 4.0 ft Cross Section 3 – Elevation 10.0 ft Cross Section 4 – Elevation 7.6 ft Cross Section 5 – Elevation 5.7 ft

Slide2 Outputs:

Available outputs from the Slide2 Stability Analysis Software include color coded images showing locations of failure surfaces and their respective factors of safety (FOS). This output can be found within Appendix D and includes the following items:

1. A to scale cross section of the slope based on the survey data;

2. Visual depiction of the soil layers within the cross section;

3. Location of the water table used in the analysis;

4. The lowest Factor of Safety computed in the analysis (green label) and additional failure surfaces throughout the cross section (black label);

5. Since no failure surfaces had Factor of Safety value below the minimum value outlined in Table 3-1 of EM

1110-2-1902, and/or the failure was shallow/surficial, the model output was adjusted to show additional failure surfaces in excess of recommended Factor of Safety values; and

6. A color-coded key depicting the factor of safety for each of the failure surface lines.

6.1.3 STABILITY RESULTS

The results of the stability analyses are presented from Table 6 - 1 to

Princeton Hydro, LLC Page | 17

Table 6 - 5. Each table depicts the lowest factor of safety computed in the analysis in comparison to the required minimum factors of safety as outlined in EM 1110-2-1902. It should be noted that seismic analysis is not covered under EM 1110-2-1902. Therefore, the factor of safety utilized for Case IV was determined following the guidelines presented in EM 1110-2-1913 (Design and Construction of Levees). For further context, the previous version of EM 1110-2-1902 notes that a minimum factor of safety of 1.0 should be used for pseudo static seismic analyses.

Generally, the circular and non-circular failure surfaces presented similar factors of safety. Neither search method presented scenarios where the output fell below the recommended FOS values outlined in the referenced documents above except the Left-to-Right Analysis of Cross Section 3. This analysis yielded a shallow surficial failure surface below the acceptable factor of safety. However, as this is contained within a very small portion of the slope and there are no deep-seated failure surfaces below the recommended factor of safety in the remainder of the slope, it is believed that this can be addressed with regular maintenance. Detailed model output can be found within Appendix E.

Table 6 - 1: Results of Stability Analysis - Cross Section 1

Analysis Condition Failure Direction Failure Surface

Calculated Lowest Factor of

Safety (FOS)

Required Minimum Factor of Safety (FOS)

Δ

End of Construction Left to Right Circular 2.0 1.3 +0.7

End of Construction Left to Right Non-Circular 1.9 1.3 +0.6

Seismic Left to Right Circular 1.6 1.0 +0.6

Seismic Left to Right Non-Circular 1.4 1.0 +0.4

Table 6 - 2: Results of Stability Analysis - Cross Section 2

Condition Failure Direction Failure Surface

Calculated Lowest Factor of

Safety (FOS)

Required Minimum Factor of Safety (FOS)

Δ

End of Construction Left to Right Circular 2.0 1.3 +0.7

End of Construction Left to Right Non-Circular 1.9 1.3 +0.6

Seismic Left to Right Circular 1.5 1.0 +0.5

Seismic Left to Right Non-Circular 1.5 1.0 +0.5

Princeton Hydro, LLC Page | 18

Table 6 - 3: Results of Stability Analysis - Cross Section 3

Analysis Condition Failure Direction Failure Surface

Calculated Lowest Factor of

Safety (FOS)

Required Minimum Factor of Safety (FOS)

Δ

End of Construction Left to Right Circular 0.9* 1.3 -0.4*

End of Construction Left to Right Non-Circular 0.9* 1.3 -0.4*

Seismic Left to Right Circular 0.8* 1.0 -0.2*

Seismic Left to Right Non-Circular 0.8* 1.0 -0.2*

End of Construction Right to Left Circular 3.5 1.3 +2.2

End of Construction Right to Left Non-Circular 3.5 1.3 +2.2

Seismic Right to Left Circular 2.4 1.0 +1.4

Seismic Right to Left Non-Circular 2.4 1.0 +1.4

*Notes surficial a failure surface with a Factor of Safety less than the recommended values that is not a concern for overall stability

Table 6 - 4: Results of Stability Analysis - Cross Section 4

Condition Failure Direction Failure Surface

Calculated Lowest Factor of

Safety (FOS)

Required Minimum Factor of Safety (FOS)

Δ

End of Construction Left to Right Circular 3.9 1.3 +2.6

End of Construction Left to Right Non-Circular 3.8 1.3 +2.5

Seismic Left to Right Circular 2.6 1.0 +1.6

Seismic Left to Right Non-Circular 2.5 1.0 +1.5

End of Construction Right to Left Circular 7.8 1.3 +6.5

End of Construction Right to Left Non-Circular 7.7 1.3 +6.4

Seismic Right to Left Circular 3.6 1.0 +2.6

Seismic Right to Left Non-Circular 3.5 1.0 +2.5

Princeton Hydro, LLC Page | 19

Table 6 - 5: Results of Stability Analysis - Cross Section 5

Analysis Condition Failure Direction Failure Surface

Calculated Lowest Factor of

Safety (FOS)

Required Minimum Factor of Safety (FOS)

Δ

End of Construction Left to Right Circular 1.7 1.3 +0.4

End of Construction Left to Right Non-Circular 1.5 1.3 +0.2

Seismic Left to Right Circular 1.3 1.0 +0.3

Seismic Left to Right Non-Circular 1.2 1.0 +0.2

End of Construction Right to Left Circular 7.0 1.3 +5.7

End of Construction Right to Left Non-Circular 6.9 1.3 +5.6

Seismic Right to Left Circular 3.6 1.0 +2.6

Seismic Right to Left Non-Circular 3.6 1.0 +2.6

7. RECOMMENDATIONS

7.1 INITIAL SITE CLEARING, EXCAVATION, GRADING, AND EARTHWORK

1. During site preparation activities, clearing and grubbing of vegetation and stripping of topsoil should be performed within and a minimum of 10 feet beyond the area of the proposed improvements.

2. All topsoil may be stockpiled for later use as fill in landscaped areas, but must not be placed as controlled, compacted fill for structural components of the site.

3. Where possible, earthwork should consist of the use of imported granular structural fill. These materials will be uncontaminated and contain no more than 25% fines (USCS).

4. Following excavation or before placing structural fill to achieve proposed grades below structures, paved areas, utilities, or significant structural fills:

a. The surface of exposed soils must be proof rolled using the procedure outlined in Section 7.2 Proof Rolling. If groundwater is encountered during earthwork operations, it may be necessary to utilize construction dewatering techniques to maintain workably dry, stable and safe conditions.

b. All fill must be placed in horizontal layers at a maximum of 12 inches in loose thickness and compacted to the densities as indicated in Table 7-1 . In areas inaccessible to large self-propelled vibratory compaction equipment, fill must be reduced to six (6) inch thick loose lifts and compacted with portable equipment to similar densities.

Princeton Hydro, LLC Page | 20

Table 7 - 1: Recommended Minimum Compaction Requirements

Location ASTM D698 Standard Proctor ASTM D1557 Modified Proctor

Foundations 98% 95%

Site Pavements 98% 95%

7.2 PROOF ROLLING

1. Following clearing, grubbing, and topsoil removal, the locations proposed to receive structures or structural fill must be proof rolled using the procedure outlined herein, unless specifically stated otherwise.

a. The area(s) to be proof rolled shall be inspected by the on-site geotechnical engineer to ensure all unwanted materials have been removed.

b. Proof rolling and compaction will commence with at least (4) passes of a heavy (minimum 10-ton static weight) self-propelled vibratory roller. In areas inaccessible to a large roller, the subgrades shall be inspected by the geotechnical engineer.

c. If the elevation of subgrade to be proof rolled is less than 24 inches above the water table, proof rolling shall be completed using a static rolling method or inspected by the geotechnical engineer for approval.

2. Upon certification of the soil surface suitability to accept fill materials or structures, the area(s) shall receive the proposed structural treatment or shall be protected from further damage by a protective cover (i.e., sacrificial soil layer, plastic covering, etc.).

7.3 SUBGRADE GUIDANCE

During the construction of foundations and any slabs-on-grade the following guidelines should be followed to provide adequate control of the exposed subsoils, and verify the conditions of encountered materials:

1. Exposed subgrades should be inspected and approved by a geotechnical engineer prior to the installation of the construction materials, but after excavation to proposed bearing surfaces.

2. If any loose, soft, or inadequate soils are encountered those materials should be remediated or removed and replaced with:

a. Dense Graded Aggregate – placed in lifts not exceeding eight (8) inches in loose thickness and compacted with vibratory compaction equipment to 95% of the maximum dry density in conformance with ASTM D1557; or

b. Controlled Low Strength Material (CLSM) – placed in wet lifts not exceeding five (5) feet in thickness and allowed 24 hours of curing time prior to placement of additional lifts of CLSM, forms, reinforcing steel, or foundation concrete. This material shall conform with ACI 229R-99 and all requirements contained therein; or

c. Structural Fill – placed in lifts not exceeding 12 inches in loose thickness and compacted with vibratory compaction equipment to 95% of the maximum dry density in conformance with ASTM D1557, comprised of imported fill. Imported fill shall consist of uncontaminated, coarse grained soil with no more than 25% passing the No. 200 U.S. standard sieve size.

7.4 DEWATERING

Groundwater was encountered across the site at depths between 5.0 and 9.5 feet below the existing ground surface. As previously stated, groundwater levels will seasonally fluctuate due to variations in the amount of

Princeton Hydro, LLC Page | 21 precipitation, evaporation, and surface water runoff. Therefore, the project documents should include provisions for the performance of dewatering. While many dewatering options exist (i.e., sump pits, bypass system, etc.) the actual dewatering utilized will be a component of the contractor’s means and methods to facilitate construction.

It is recommended that a “dewatering plan” be a required submittal to ensure that the contractor develops an appropriate plan prior to commencing with construction. The contractor should not attempt to lower the groundwater surface beneath which is required to facilitate construction.

7.6 EXCAVATION SAFETY

All excavations should be performed in accordance with OSHA guidelines. The site soils cannot be generalized as a singular type (per OSHA CFR 1926 Excavation Standards) and should instead be considered Multi-Layered.

The soil must be classified on the basis of the soil classification of the weakest soil layer. Each layer may be classified individually if a more stable layer lies below a less stable layer (i.e., where Type C rests on top of stable rock). Should it be required, all temporary sheeting and shoring should be designed by a qualified engineer licensed in the State of New York.

8. QUALITY CONTROL

A qualified geotechnical engineer should be retained to provide continuous on-site observation during foundation installation and earthwork operations. Close observation is required to assure adherence to the above recommendations and design concepts and allow for site specific construction modifications and design changes in the event subsurface conditions encountered are different from those anticipated.

9. LIMITATIONS

As a result of the approved scope of services, the encountered subsurface conditions, and in conjunction with current professional standards the following limitations are provided.

1. It is noted that this investigation was limited to those locations as depicted on the soil exploration location map within this report. Conditions may vary across the site.

2. Observations, conclusions, and recommendations contained in this report are based upon the applicable standards of our profession at the time the report was prepared.

3. The stratification lines shown on each subsurface log represent an approximate boundary between soil types. The specific boundary types and features are indicated in the logs.

4. The final logs represent our interpretation of the contents of the field logs, field testing, observations made in the laboratory, and the results of laboratory testing.

5. The recommendations enclosed herein are based on the final logs and the information presented herein.

6. Water level readings have been made in the explorations at times and under conditions stated on the individual subsurface logs. These data have been reviewed and interpretations made in the body of this report. However, it must be noted that fluctuations in the level of groundwater may occur due to variations in time of year, rainfall, temperature, and other factors.

7. Unless specifically indicated to the contrary within this report, the scope of our services was limited to the investigation, laboratory analysis, and report for the Spring Creek North Park Ecosystem Restoration Project located in Queens, New York for the sole use of the United States Army Corps of Engineers, the New Jersey Department of Environmental Projection, and their delegated representatives and consultants.

8. This report is not suitable for the implementation of any other project without written confirmation from the design professional who prepared this report.

9. This report has been prepared in accordance with several accepted soils practices for the exclusive use of the client. No other warranty expressed or implied is made.

Princeton Hydro, LLC Page | 22

10. The conclusions and recommendations discussed within this report are based in part upon the data obtained from the soil borings completed during field investigation activities for this scope of services. The nature and extent of variations between any individual exploration locations may not become apparent until construction proceeds. If unforeseeable variations are encountered during construction, it will be necessary to reevaluate the recommendations of this report.

11. A qualified geotechnical engineer should be retained to provide continuous on-site observation during installation operations. This will serve to ensure compliance with the design concepts and recommendations and to allow changes in the event the conditions differ from those anticipated prior to the start of construction.

12. This investigation was not intended to assess the property for the presence or nature of contamination.

13. The engineering design parameters and qualities are provided with the assumptions and additional limitations indicated throughout the report. If any of those assumptions prove to be invalid the recommendations and parameters provided in this report will need to be revisited and revised.

14. This report attempts to generalize a highly heterogeneous natural system to simplify discussion of the subsurface features. This inherently requires the aggregation of specific soil qualities. The relative importance of different soil qualities may vary as the project progresses. The recommendations and observations provided apply a suitable amount of aggregation based on the available information at the time this report was prepared. Princeton Hydro reserves the right to revise this report as needed to account for changes in the design, encountered site conditions, or other unforeseeable conditions.

Princeton Hydro, LLC

APPENDIX A

FIELD TESTING LOCATION MAP

Wx Wx W x Wx Wx Wx Wx Wx

W x

W x

Wx

W x

X

X X

X

X

X X

X

X

X

X

X X

X X

X X X X

X

X

X

X

X X

X X

X

X

X X

X X

X

X

X X

X X

X

X

X

X

X X

X X

X X

X X

X X

X X

X

X X

X X

X X X X

X X

X X

X

X

X

X

X

X

X

XX

X

X

X

X X

X

X

X

X X

X

X X

XXXX

XXXXXXXXXXXXX

X

X

X X

X

X

X

X X

X

X

V

V

U

U

U

V

V

V

V

U

U U

U U

U

U

U

U

U

U

U U

U

U

U

V

U U U

V

U U

U

V

U U

U

U

SSx SSx

SDx

SDx

SDx

Gx GxGx Gx

GxGx

G x

G x

G x

Gx Gx

FOS FOS FOS FOS FOS

GxGx GxGx Gx

W x

Wx

Gx

SD

x

O H

Tx O

H Tx

O HTx

O HTx

O HTx

O HTx

O HTx

O HTx

OHTx

OHTx

OHTx

O HTx

SD

x

SD

x

SDx

SS

x

SS

xSSx

SSx SS x

SS

xSSx

SSx

SSx SSx

SSx

SSx SSx SSxSSx SSx SSx

SSxSSx

SSxSSxSSxSSxSSx SSx

SSx

SS

x

SSx

SSx SSx

SSx

SSx

SSx SSx SSx SSx SSx

SSxSSxSSxSSxSSx SSx

SSx

SS

x

SSx

SSx

SSx

SSx

SSx SSx SSx SSx SSx SSx

SSx

SSx

FOUNTAIN AVE.

BELT PKWY

FLATLANDS AVE.

75TH ST

157TH ST

SPRING CREEK RALPH'S CREEK

SPRING CREEK

AUXILIARY WASTEWATER

TREATMENT PLANT

B-1

B-2

B-3

B-6

B-7

B-8

B-4

B-9

B-10

B-11

B-5

SO

LI

C

IT

AT

IO

N N

O

D

ES

IG

N

ED

B

Y:

D

ES

C R

IP

TI

O N

A

M

AR

K

SI

ZE

SU

BM

IT

TE

D B

Y:

D

AT

E

C O

N

TR

AC

T

N O

C

H

EC

KE

D

B Y:

D R

AW

N

B Y:

IS

SU

E D

AT

E:

SHEET ID

B

C

D

E

F

G

2 3 4 5 6 7 8 9 10

US Army Corps of Engineers

U .S

. A R

M Y

C O

R

PS

O F

EN

G

IN

EE

R S

AN

SI

D

W

2D S-

-D

-0

W

2D S-

-F

-0

N O

VE

M

BE

R

N

EW

Y O

R K, N Y

8-

F

ED

ER

AL

P

LA

ZA

N

EW

Y

O R

K D

IS

TR

IC

T

N

EW

Y O

R K

C

IT

Y

PA

R

KS

N

EW

Y

O R

K C

IT

Y, N

EW

Y O

R K

BO

R

O U

G H

S O

F

BR

O O

KL

YN

Q

U

EE

N S

EC

O

SY

ST

EM

R

ES

TO

R

AT

IO

N

P R

O

JE

C T

SP

R

IN

G

C R

EE

K

N O

R

TH

60% SUBMISSION - NOT FOR CONSTRUCTION

N

1" = 150'-0"

( IN FEET )

GRAPHIC SCALE

B-101

BO

R

IN

G

L O

C

AT

IO

N

P

LA

N

R W

R W

C P

PR

IN

C

ET

O N

H

YD

R O

BORING LEGEND

BORING LOCATION SYMBOL

BORING LOCATION SUMMARY TABLE

ID NORTHING EASTING LATITUDE LONGITUDE

B-1 179534 1023085 40.6594 -73.8600

B-2 179457 1023088 40.6592 -73.8600

B-3 179255 1023266 40.6586 -73.8594

B-4 179352 1022658 40.6589 -73.8616

B-5 178910 1022754 40.6577 -73.8612

B-6 179122 1021819 40.6582 -73.8646

B-7 179462 1021621 40.6592 -73.8653

B-8 179738 1021731 40.6599 -73.8649

B-9 179867 1022175 40.6603 -73.8633

B-10 179976 1022518 40.6606 -73.8621

B-11 179103 1022695 40.6582 -73.8614

APPENDIX B

FIELD LOGS

Boring terminated at 27.0 fbgs. Groundwater encountered at 6.0 fbgs.

S-1

S-2

S-3

S-4

S-5

S-7

S-8

S-9

S-10

SS

SS

SS

SS

SS

SS

SS

SS

SS

Groundwater encountered at 6.0 fbgs

ST-1 advanced from

10.0 fbgs to 12.0 fbgs.

24" recovery.

S-7: Gravel: 0.0%, Sand:

55.0%, Fines 45.0%.

Moisture Content: 73.5%

PL=43, LL=124, PI=81

S-9: Gravel: 0.0%, Sand:

95.8%, Fines: 4.2%.

Moisture Content: 20.3%

PL=19, LL=NP, PI=NP

0.5 1.0

2.5

3.5 4.0

8.0

10.0

13.0

14.0

20.0

25.0

27.0

6.0'

Dark brown to black silty sand (SM), Topsoil, loose, moist.

Black gravelly medium sand (SP), decomposed asphalt, loose, moist.

Dark gray to light gray well graded fine to coarse gravel (GW), Fill, dense, moist.

Dark gray lean clay (CL), very stiff, moist.

Light gray poorly graded fine sand (SP), loose, moist.

Dark gray to black poorly graded medium to coarse gravel (GP), trace silt and fine sand, loose to medium dense, moist to wet at 6.0 fbgs.

Gray extremely gravelly clayey sand (SC), mostly fine to medium gravels, loose, wet.

Dark gray peat (PT), very soft, wet.

Black to gray clayey sand (SC), very loose, wet.

Light gray to olive brown well graded fine to medium sand (SW), trace fine gravels throughout, medium dense, wet.

Light gray to gray poorly graded medium sand (SP), medium dense, wet.

Gray to grayish brown well graded very fine to medium sand (SW), trace silt, loose, wet.

ST

-1

-1

-3

-5

-7

-9

-11

-13

-15

-17

5-8-21-20

11-9-14-11

7-5-5-9

22-12-6-4

3-5-2-4

WR-1-1-3

4-6-9-8

13-7-8-9

3-4-5-7

Spring Creek North - Task 03 Geotechnical Investigation

Split Spoon

United States Army Corps of Engineers - New York District 1/12/2022 1/12/2022

27.0 Matt Pappas

DE

PT

H (fe et

SAMPLES

No

Type Blows/6" SS or RQD Ground Surface

DESCRIPTION

NAME (USCS,USDA): color, moist, % by wt., plast. density, structure, cementation, react. w/HCl, geo. inter. REMARKS

PROJECT:

BORING LOCATION:

DRILLING CONTRACTOR: DRILLING METHOD:

DRILLING EQUIPMENT:

SAMPLING METHOD:

CLIENT:

DATE AND TIME

STARTED:

DATE AND TIME

FINISHED:

TOTAL DEPTH (ft.):

LOGGED BY:

LOG OF BORING:

B-1

See Boring Location Map

Boring Brothers, Inc. Mud Rotary CME 55LCX Tracked Rig

NORTHING: EASTING: ELEV.:179,534 1,023,085 10.0

PROJECT NUMBER:

DRILLER/HELPER:

DATUM (H,V):

PLUNGE/TREND:

1880.012

NAD83, NAVD88

Depth, GW bpf

Rob 90

ELEVATION

(feet)

12770 Flatlands Avenue

SITE ADDRESS:

Brooklyn, New York

PROJECT NO.:Princeton Hydro LLC | 1200 Liberty Place | Sicklerville, NJ 08081 Page 1 of 11880.012

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

S-9

SS

SS

SS

SS

SS

SS

SS

SS

SS

Groundwater encountered at 6.0 fbgs

S-4 & S-5: Gravel: 32.0%, Sand: 47%, Fines: 21%.

Moisture Content:

22.0%, PL=26, LL=39,

PI=13

S-8: Gravel: 0.7%, Sand:

96.3%, Fines: 3.0%.

Moisture Content:

23.2%, PL=19, LL=NP,

PI=NP

0.33

1.0

4.5

6.0

10.0

12.0

25.0

27.0

6.0'

Dark brown silty sand (SM), Topsoil, many fine roots throughout, loose, moist.

Black gravelly medium sand (SP), Asphalt, brick fragments noted, little fine to medium gravels, loose, moist.

Dark gray to light gray well graded fine to coarse gravel (GW), Fill, medium dense, moist.

Gray fat clay (CH), medium, moist to wet at 6.0 fbgs.

Dark gray silty sand with gravel (SM), little fine to medium gravels throughout, very loose to medium dense, wet.

Dark gray peat (PT), some clayey sand and lean clay intermixed throughout, medium, wet.

Dark reddish brown to light gray poorly graded medium sand (SP), loose, wet.

Light gray well graded fine to medium sand (SW), medium dense, wet.

-1

-3

-5

-7

-9

-11

-13

-15

-17

7-6-13-16

10-12-17-28

19-8-8-9

21-15-3-1

7-2-2-3

4-3-2-3

8-9-8-7

5-4-5-6

6-4-7-4

Spring Creek North - Task 03 Geotechnical Investigation

Split Spoon

United States Army Corps of Engineers - New York District 1/12/2022 1/12/2022

27.0 Matt Pappas

DE

PT

H (fe et

SAMPLES

No

Type Blows/6" SS or RQD Ground Surface

DESCRIPTION

NAME (USCS,USDA): color, moist, % by wt., plast. density, structure, cementation, react. w/HCl, geo. inter. REMARKS

PROJECT:

BORING LOCATION:

DRILLING CONTRACTOR: DRILLING METHOD:

DRILLING EQUIPMENT:

SAMPLING METHOD:

CLIENT:

DATE AND TIME

STARTED:

DATE AND TIME

FINISHED:

TOTAL DEPTH (ft.):

LOGGED…