GeotechnicalReport.pdf

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GEOTECHNICAL ENGINEERING REPORT

PROPOSED BUILDING ADDITIONS

81 FOURNIER STREET

NEW HAVEN, CONNECTICUT

Prepared for:

City of New Haven 200 Orange Street, 5th Floor

New Haven, Connecticut 06510

Prepared by:

Down To Earth Consulting, LLC 27 Siemon Company Drive - Suite No. 363 West

Watertown, Connecticut 06795

File No. 0063-022.00

June 2023

June 9, 2023 File No. 0063-022.00

Zach Shapiro, P.E.

City of New Haven 200 Orange Street 5th Floor New Haven, Connecticut 06510

Via email: ZShapiro@newhavenct.gov

Re: Geotechnical Engineering Report 81 Fournier Street Building Additions

New Haven, Connecticut

Dear Mr. Shapiro:

Down To Earth Consulting, LLC (DTE) is pleased to submit this geotechnical engineering report for the proposed building additions that will be located at 81 Fournier Street in New Haven, Connecticut. We appreciate this opportunity to work with you. Please call if you have any questions.

Sincerely, Down To Earth Consulting, LLC

Daniel F. LaMesa, P.E.

Principal

81 Fournier Street Building Additions New Haven, Connecticut

File No. 0063-022.00 – June 12, 2023 Page No. i

TABLE OF CONTENTS

1.0 INTRODUCTION

2.0 TEST BORINGS

3.0 SUBSURFACE CONDITIONS

3.1 SUBSURFACE PROFILE

3.1.1 Fill

3.1.2 Natural Sand Deposits

3.2 GROUNDWATER

4.0 GEOTECHNICAL RECOMMENDATIONS

4.1 FOUNDATIONS

4.1.1 Foundation Type and Bearing Strata

4.1.2 Footing Levels and Sizes

4.1.3 Allowable Bearing Pressures and Settlement Estimates

4.2 SLAB-ON-GRADE

4.2.1 Subgrade

4.2.2 Drainage and Damp-Proofing

4.3 RETAINING WALLS

4.4 SEISMIC DESIGN

5.0 MATERIALS RECOMMENDATIONS

5.1 ON-SITE MATERIALS

5.2 COMPACTED GRANULAR FILL

5.3 SAND AND GRAVEL

5.4 CRUSHED STONE

5.5 PROCESSED AGGREGATE

5.6 GEOTEXTILE FABRIC

5.7 PLACEMENT AND COMPACTION REQUIREMENTS

6.0 CONSTRUCTION RECOMMENDATIONS

6.1 FOOTING PREPARATION

6.2 TEMPORARY EXCAVATIONS

6.3 TEMPORARY GROUNDWATER CONTROL

7.0 REVIEW OF FINAL DESIGN, PLANS, AND SPECIFICATIONS

8.0 CONSTRUCTION QUALITY CONTROL

9.0 LIMITATIONS

APPENDICES

APPENDIX 1 – FIGURES

APPENDIX 2 – BORING LOGS

APPENDIX 3 – LIMITATIONS

Page No. 1

1.0 INTRODUCTION

This report provides geotechnical design and construction recommendations for the proposed building additions that will be located at 81 Fournier Street in New Haven, Connecticut. Refer to Figures 1 and 2 (in Appendix 1) for the approximate site and proposed addition locations, respectively.

We understand two single-story additions will be constructed off the western and eastern ends of the existing animal shelter building. The proposed structures will be about 450 to 1,655 square feet with slabs-on-grade (i.e., no basement) that generally matches the first-floor level of the existing building. Foundation and slab loads were not available at the time this report was prepared. Associated parking areas, sidewalks, drainage structures, utilities, and landscape areas will also be constructed.

Our geotechnical engineering services included: reviewing project plans, drilling test borings, characterizing subsurface conditions within the project limits, performing geotechnical engineering analyses, and providing geotechnical design and construction recommendations for the proposed additions. Our services were performed in accordance with our May 16, 2023 proposal.

Our recommendations are based on allowable stress design methods and the 2021 International Building Code with 2022 Connecticut Supplements (Building Code).

2.0 TEST BORINGS

We observed and logged two test borings (B-1 and B-2) drilled by our subcontractor Associated Borings Co., Inc. on May 26, 2023. Boring locations are depicted on Figure 2 (Appendix 1) and the logs are included in Appendix 2. Borings were located in the field by taping/pacing from existing site features and should be considered approximate.

The borings were drilled to explore the soil and groundwater conditions in the project area. Hollow-stem auger drilling methods were used to advance borings to depths of approximately 17 to 22 feet below existing grades. All borings were terminated in natural soil.

Representative soil samples were obtained for soil classification by split barrel sampling procedures in general accordance with ASTM D-1586. The split-spoon sampling procedure utilizes a standard 2-inch O.D. split-barrel sampler that is driven into the bottom of the boring with a 140-pound hammer falling a distance of 30 inches. The number of blows required to advance the sampler the middle 12-inches of a normal 24-inch penetration is recorded as the Standard Penetration Resistance Value (N). The blows (i.e., “N-Value”) are indicated on the boring logs at their depth of occurrence and provide an indication of the relative consistency of the material.

Groundwater levels were measured using a weighted tape in open drill holes or inferred from wet soil samples during drilling.

Page No. 2

3.0 SUBSURFACE CONDITIONS

3.1 SUBSURFACE PROFILE

The generalized subsurface profile, as inferred from the subsurface data, consists of Fill over Natural Sand Deposits. The following is a more detailed description of the major subsurface materials encountered at the site:

3.1.1 Fill

Uncontrolled Fill was encountered at each boring location. This stratum extended down about 5 to 7 feet below existing site grades and typically consisted of loose, gray/brown, fine to coarse sand with varying amounts (0 to 20%) of silt and trace (0 to 10%) gravel.

The thickness, character, and consistency of the Fill will vary between boring locations. Samples obtained from this stratum generally did not have foreign (e.g. asphalt, concrete, etc.) or deleterious (e.g. organics) materials and in some areas appeared to be reworked native soil.

3.1.2 Natural Sand Deposits

Natural Sand Deposits were encountered below the uncontrolled Fill. This material generally consisted of loose to medium dense, gray/reddish brown, fine to coarse sand with trace amounts of silt.

3.2 GROUNDWATER

Groundwater was encountered at about 7 to 10 feet below grade during drilling. Groundwater levels measured in the boreholes may not have had sufficient time to stabilize and should be considered approximate. Groundwater levels will vary depending on factors such as temperature, season, precipitation, construction activity, and other conditions, which may be different from those at the time of these measurements.

4.0 GEOTECHNICAL RECOMMENDATIONS

We offer the following geotechnical design recommendations based on the subsurface conditions encountered at the site, available project information, and proposed construction.

4.1 FOUNDATIONS

4.1.1 Foundation Type and Bearing Strata

We recommend supporting the proposed building additions on conventional, shallow spread footings. The footings should bear on undisturbed Natural Sand Deposits, or on Structural Fill (hereinafter specified as Compacted Granular Fill, CGF) over Natural Sand. Actual bottom of unsuitable bearing material elevations will vary across the site and should be verified during construction excavation by a DTE representative.

Page No. 3

When CGF is used beneath the footings (e.g., in fill areas), we recommend that it be placed one foot beyond the edge of the footings and at a one horizontal to one vertical slope away and down from the bottom outside edge of the footings. Crushed Stone can be used in place of CGF as it is much easier to compact.

4.1.2 Footing Levels and Sizes

Exterior footings (and footings in unheated areas) should be constructed at a minimum frost depth of 42-inches below proposed site grades. Interior footings, in heated areas, should be constructed at a minimum depth of 18-inches below proposed top of slab-on-grade level.

The minimum footing width should be 2 feet.

4.1.3 Allowable Bearing Pressures and Settlement Estimates

We recommend a maximum allowable design bearing pressure of four kips per square foot (ksf) for footings bearing on the recommended bearing materials. Based on the recommended bearing strata and anticipated loads, we anticipate that footings will undergo less than one inch of total settlement and less than a half inch of differential settlement. Settlements will occur as the loads are applied and are expected to be complete at the end of construction.

DTE should be provided the final foundation loads and geometries once they are available to confirm the above recommended bearing capacity and settlement estimates.

4.2 SLAB-ON-GRADE

4.2.1 Subgrade

We recommend placing the at-grade slab over a minimum six-inch-thick base course layer of compacted Crushed Stone placed over the surface of natural Sand and/or the existing Fill that has been improved with surface densification under the observation of a qualified Geotechnical Engineer. This procedure consists of removing all surficial organic and debris materials and compacting the surface with a minimum of four passes with a 20-ton vibratory drum roller having a minimum dynamic force of 6,000 lbs. per foot of drum width. Areas exhibiting instability shall receive additional compaction and/or be over-excavated and replaced with Compacted Granular Fill (CGF), as recommended by the Geotechnical Engineer. Modifications to this procedure may be required if the subgrade is saturated or groundwater table is too high.

The subgrade modulus for the recommended subgrades and base course is 250 pounds per cubic inch.

4.2.2 Drainage and Damp-Proofing

Groundwater appears to be below the proposed slab level, thus, sub-slab drains are not required.

Damp-proofing of the slabs is recommended. Slab damp-proofing must be installed between the slab and base course, and consist of not less than 6-mil polyethylene with joints lapped at least 6-inches.

Page No. 4

4.3 RETAINING WALLS

We recommend backfilling earth retaining structures with compacted Sand and Gravel and installing footing drains. Walls that are free to rotate at the top and are not braced should be designed to resist an equivalent active static horizontal fluid earth pressure equal to 35 pcf (based on φ’ = 34°, c = 0, Ka = 0.28, and ɣ = 125 pcf). Braced retaining walls should be designed to resist an equivalent at-rest static horizontal fluid earth pressure equal to 55 pcf (based on φ’ = 34°, c = 0, Ko = 0.44, and ɣ = 125 pcf). This assumes level backfill soils and no unbalanced hydrostatic pressures, seismic forces, or surcharge loads (e.g., vehicles).

Due to the limited expected wall movement and depth of footings, we do not recommend the use of passive earth pressures against the base of walls. We recommend a maximum coefficient of friction of 0.45 between foundations and the recommending bearing strata.

4.4 SEISMIC DESIGN

The site class is “D” per the Building Code. Based on the standard penetration test results, visual soil classification, and design peak ground acceleration at this locale, the site soils are not susceptible to liquefaction.

5.0 MATERIALS RECOMMENDATIONS

5.1 ON-SITE MATERIALS

Based on our visual soil classifications, some site soils may be reusable as Compacted Granular Fill (CGF) if they meet the requirements in Section 5.2. Site soils can be reused as General Fill outside the building and deeper than 12-inches below pavement if the material does not contain organics or significant amounts (less than 2%) of debris materials. The elevated fines (i.e., soil particles passing the No. 200 sieve) content of some site soils could make them difficult to place and compact. Success in using these materials will depend on their moisture content and prevailing weather conditions when they are excavated, placed, and compacted.

Topsoil and soil with organics should only be reused in landscaped areas for planting grass and other vegetation.

5.2 COMPACTED GRANULAR FILL

Compacted Granular Fill (CGF) for use as structural fill below footings and other structures shall consist of inorganic soil free of clay, loam, ice and snow, tree stumps, roots, and other organic matter; graded within the following limits:

Sieve Size Percent finer by weight

4-inches 100%

No. 10 30 - 100

No. 40 10 - 90

No. 200 0 - 12

Page No. 5

5.3 SAND AND GRAVEL

Sand and Gravel for use as retaining wall backfill and below slabs shall consist of hard, durable sand and gravel; free of ice, clay, shale, roots, sod, rubbish, and other organic matter; graded within the following limits:

2-inches 100%

1/2-inch 50 - 85

No. 4 40 - 75

No. 40 10 - 35

No. 200 0 - 5

5.4 CRUSHED STONE

Crushed Stone for use around drains or below foundations and slabs shall consist of sound, tough, durable, rock that is graded within the following:

5/8-inches 100%

1/2-inch 85 - 100

3/8 inch 15 - 45

No. 4 0 - 15

No. 8 0 - 5

5.5 PROCESSED AGGREGATE

Processed Aggregate Base for use as pavement base shall consist of inorganic soil free of clay, loam, ice and snow, tree stumps, roots, and other organic matter; graded within the following limits:

Sieve Size Percent finer by weight

2 1/2-inches 100%

2-inch 95 - 100

3/4-inch 50 - 75

1/4-inch 25 - 45

No. 40 5 - 20

No. 100 2 - 12

5.6 GEOTEXTILE FABRIC

Geotextile fabric placed around crushed stone pipe bedding or used as a separation fabric for crushed stone and soil material should meet the following criteria:

Page No. 6

Property Criteria Test Method Grab Strength min. 80lbs ASTM D4632 Static (CBR) Puncture min. 50lbs ASTM D6241 Trapezoid Tear min. 25lbs ASTM D4533 Apparent Opening Size No. 70-100 U.S. Sieve Size ASTM D4751

Fabric should be needle-punched non-woven material. Seams should be overlapped a minimum of six inches. During stone placement, the stone drop height should not exceed three feet and equipment traffic should be kept off the fabric until at least 6 to 12 inches of material is placed.

5.7 PLACEMENT AND COMPACTION REQUIREMENTS

The required degree of compaction shall be based on a maximum dry density as determined by a Modified Proctor (ASTM D1557). The degree of compaction for fill placed in various areas shall be as follows:

Placement areas Minimum degree of compaction

1. Below foundations (footings) 95%

2. Below slabs and Pavement 92%

3. Against foundation and retaining walls 92%

4. Landscaped areas 90%

Crushed stone is considered to be self-compacting, and would negate the need to run laboratory proctor testing and have field density testing of in-place lifts. The crushed stone should be plate compacted to “chink up” the working surface in lifts. We recommend placing Crushed Stone in maximum 12-inch lifts and compacting the lifts with a minimum of four passes with a vibratory plate compactor weight of a minimum of 1,000 pounds and with a minimum centrifugal force of 10,000 pounds. Recommended loose lift thickness for granular fill and the minimum number of passes of compaction equipment are summarized on the table below.

Extra care should be used when compacting adjacent to walls. Hand-operated rollers or plate compactors weighing not more than 250 pounds should be used within a lateral distance of 5 feet of walls. Where walls are buried on both sides, backfill and compaction should proceed on both sides of the wall so that the difference in top of fill on either side of the wall does not exceed 2 feet.

Page No. 7

Maximum

Loose Lift Thickness Minimum

Number of Passes

Compaction

Method

Maximum Stone Size

Below Structures

Less Critical Areas

Below Structures

Less Critical Areas

Hand-operated vibratory plate or light roller in confined areas 4” 6” 8” 6 4

Hand-operated vibratory drum rollers weighing at least 1,000# 6” 8” 10” 6 4

Light vibratory drum roller, minimum dynamic force

3,000# per ft. of drum width 6” 10” 14” 6 4

Medium vibratory drum roller, minimum dynamic force 5,000# per ft. of drum width

8” 12” 18” 6 4

Large vibratory drum roller, minimum dynamic force

8,000# per ft. of drum width 10” 16” 24” 6 4

6.0 CONSTRUCTION RECOMMENDATIONS

6.1 FOOTING PREPARATION

The existing Fill and buried structures (e.g. utilities) are not suitable for support of conventional, shallow foundations and must be excavated in its entirety from the proposed foundation areas.

Actual bottom of unsuitable bearing soil elevations will vary across the site and should be verified during construction excavation by a DTE representative.

We recommend the use of smooth edged excavator buckets or clips (not back-bladed) to make the final excavation to help protect the subgrade. The base of footing excavations should be free of debris materials, organics, water, ice, and loose and frozen soils prior to placing concrete.

Should the materials at bearing level become disturbed, the affected materials should be removed and/or repaired prior to placing concrete. Concrete should be placed as soon as possible after excavation so that excessive weathering of bearing materials does not occur. A four-inch-thick layer of compacted Crushed Stone can be used below foundations to protect footing subgrades during construction and facilitate dewatering (as needed).

6.2 TEMPORARY EXCAVATIONS

The Fill and natural site soils are classified as OSHA Class “C” soil and can be cut at a maximum one vertical to one and a half horizontal (1V:1.5H) slope up to a maximum excavation depth of 20 feet. These maximum slope and excavation depths assume no surcharge load (i.e., stockpiles, construction equipment, etc.) at the top of the excavations or groundwater seepage.

Page No. 8

If excavations cannot be sloped in accordance with OSHA requirements, a temporary excavation support system will be required. The system should be chosen and installed by the contactor and designed by a Professional Engineer registered in the Connecticut.

6.3 TEMPORARY GROUNDWATER CONTROL

We expect that temporary groundwater/storm water control can largely be accomplished by means of shallow trenches and sumps, and grading the excavation to low points. The construction dewatering system means and methods should be chosen by the contractor and designed by a Professional Engineer registered in the State of Connecticut. This should include providing a discharge water management plan that avoids endangering public health and nearby property and meets applicable local, state, and environmental regulations.

7.0 REVIEW OF FINAL DESIGN, PLANS, AND SPECIFICATIONS

When project plans and specifications are available they should be provided to DTE for review of conformance with our geotechnical recommendations. If any changes are made to the proposed building, the recommendations provided in this report will need to be verified by DTE for applicability.

8.0 CONSTRUCTION QUALITY CONTROL

We recommend that DTE make field observations of excavations and foundation preparation to monitor compliance with our recommendations and project specifications. Specifically, we recommend field observation of footing subgrades, removal of unsuitable materials, Fill placement and compaction, and existing Fill improvement (e.g., surface densification) to monitor compliance with project specifications.

9.0 LIMITATIONS

This report is subject to the limitations included in Appendix 3.

APPENDIX 1 -

FIGURES

SITE

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AREA PLAN PROPOSED BUILDING ADDITIONS 81 FOURNIER STREET NEW HAVEN, CONNECTICUT

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REVIEWED BY: DFL

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DRAWN BY: MF

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SCALE 1"= 2,000'

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DATE: 6/10/2023

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FIGURE NO. 1

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PROJECT NO. 0063-022.00

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REFERENCE: USGS TOPOGRAPHIC QUADRANGLE: NEW HAVEN, CT

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27 SIEMON COMPANY DRIVE, SUITE 363W

WATERTOWN, CONNECTICUT 06795

DESIGNED BY

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CHECKED BY

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APPROVED BY

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DRAWN BY

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NO.

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DATE

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REVISIONS

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DRWN.

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APPVD

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CHKD

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PROPOSED BUILDING ADDITIONS 81 FOURNIER STREET NEW HAVEN, CONNECTICUT

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FILE NO.

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AS NOTED

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FIGURE NO.

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SCALE

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DATE

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PROJECT

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OTHERS

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MF

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DFL

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DFL

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DWG. TITLE.

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SITE AND EXPLORATION LOCATION PLAN

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SCALE 1"= 20'

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%%ULEGEND

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TEST BORING NO. AND LOCATION

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AutoCAD SHX Text NOTES: 1) BASE MAP DEVELOPED FROM AN ELECTRONIC FILE PROVIDED BY CITY OF NEW HAVEN ENTITLED 'ANIMAL SHELTER, 81 FROUNIER STREET, NEW HAVEN, CT 06511'. DATED APRIL 23, 2023, ORIGINAL SCALE 1/8"=1'-0". 2) BORINGS WERE COMPLETED BY ASSOCIATED BORING COMPANY AND OBSERVED BY DOWN TO EARTH CONSULTING, LLC. 3) THE LOCATIONS OF THE EXPLORATIONS WERE DETERMINED BY TAPING AND VISUAL ESTIMATES FROM EXISTING SITE FEATURES. THESE LOCATIONS SHOULD BE CONSIDERED ACCURATE ONLY TO THE DEGREE IMPLIED BY THE METHOD USED.

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27 SIEMON COMPANY DRIVE, SUITE 363W

WATERTOWN, CONNECTICUT 06795

APPENDIX 2 -

TEST BORING LOGS

PROJECT BORING NO.

SHEET 1 of 1

FILE NO.

CHKD. BY

Boring Co. Boring Location See Boring Location Plan Driller Ground Surface El. Datum Logged By Date Start Date End

Hammer Type: Groundwater Readings (from ground surface)

Sampler Size: Date Time Depth (ft) Elev. Stabilization Time

Type Drill Rig: 5/26/23 -

Drilling Method:

D

E

P Casing

T Blows REC/PEN DEPTH

H (ft) (inches) (feet)

2 1/23 1 to 3

4 6/24 3 to 5

6 9/24 5 to 7

8 12/24 7 to 9

11 10/24 10 to 12

16 11/24 15 to 17

21 24/24 20 to 22

1. S denotes split-barrel sampler. 7. WH denotes weight of hammer

2. ST denotes 3-inch O.D. undisturbed sample. 8. WR denotes weight of rods

3. UO denotes 3-inch Osterberg undisturbed sample. 9. PP denotes Pocket Penetrometer.

4. PEN denotes penetration length of sampler. 10. FVST denotes field vane shear test.

5. REC denotes recovered length of sample. 11. RQD denotes Rock Quality Designation.

6. SPT denotes Standard Penetration Test. 12. C denotes core run number.

SAND

B-1

PROPOSED BUILDING ADDITIONS

81 FOURNIER STREET 0063-022.00

NEW HAVEN, CONNECTICUT DFL

Donut hammer driven by cathead with 30 inch drop

1-3/8" I.D. Split Spoon

Truck Mounted CME 55 7 - After 15 min.

Associated Borings Company Jaime Lloret Not Available Not Available

Mateusz Fekieta 5/26/2023 5/26/2023

3.25-inch I.D. Hollow-Stem Augers

SAMPLE INFORMATION SAMPLE DESCRIPTION STRATA

Type BLOWS PER

FILL

S-1 2-3-3-2

Core Time

& No. 6 INCHES (min./ft)

Loose, dark brown, fine to medium SAND, some Silt, trace fine Gravel

6-9-9-8 Medium dense, grayish brown, fine to medium SAND, trace Silt

S-2 2-5-5-7 Loose, dark brown, fine to medium SAND, little Silt, trace fine Gravel

S-3

S-4 5-6-6-7 Medium dense, grayish brown to red-brown, fine to coarse SAND, trace Silt

S-5 4-5-4-4

S-6 2-2-4-4

2-5-5-2S-7

Little = 10 to 20%

Over 50 - Very Dense 16 to 30 - Very Stiff Over 30 - Hard

FIELD NOTES: 1) Stratification lines represent approximate boundaries between soil types, transitions may be gradual.

SPT N-Values SPT N-Values Proportions

Loose, red-brown, fine to coarse SAND, trace fine Gravel, trace Silt

Loose, red-brown, fine to coarse SAND, trace Silt

Loose, red-brown, fine to coarse SAND, trace Silt

END OF EXPLORATION AT 22 FEET BELOW GROUND SURFACE

2) Water level readings have been made at times and under conditions stated, fluctuations may occur due to other factors.

11 to 30 - Medium Dense 5 to 8 - Medium Stiff Some = 20 to 35%

31 to 50 - Dense 9 to 15 - Stiff And = 35 to 50%

SYMBOL KEY

0 to 4 - Very Loose 0 to 2 - Very Soft Trace = 0 to 10%

5 to 10 - Loose 3 to 4 - Soft

0063-022.00 Boring Logs Page 1 of 2 Down to Earth Consulting, LLC

PROJECT BORING NO.

SHEET 1 of 1

FILE NO.

CHKD. BY

Boring Co. Boring Location See Boring Location Plan Driller Ground Surface El. Datum Logged By Date Start Date End

Hammer Type: Groundwater Readings (from ground surface)

Sampler Size: Date Time Depth (ft) Elev. Stabilization Time

Type Drill Rig: 5/26/23 -

Drilling Method:

D

E

P Casing

T Blows REC/PEN DEPTH

H (ft) (inches) (feet)

2 6/24 1 to 3

4 7/24 3 to 5

6 2/24 5 to 7

8 12/24 7 to 9

11 9/24 10 to 12

16 18/24 15 to 17

1. S denotes split-barrel sampler. 7. WH denotes weight of hammer

2. ST denotes 3-inch O.D. undisturbed sample. 8. WR denotes weight of rods

3. UO denotes 3-inch Osterberg undisturbed sample. 9. PP denotes Pocket Penetrometer.

4. PEN denotes penetration length of sampler. 10. FVST denotes field vane shear test.

5. REC denotes recovered length of sample. 11. RQD denotes Rock Quality Designation.

6. SPT denotes Standard Penetration Test. 12. C denotes core run number.

FILL

END OF EXPLORATION AT 17 FEET BELOW GROUND SURFACE

SAND

Over 50 - Very Dense 16 to 30 - Very Stiff Over 30 - Hard

FIELD NOTES: 1) Stratification lines represent approximate boundaries between soil types, transitions may be gradual.

2) Water level readings have been made at times and under conditions stated, fluctuations may occur due to other factors.

11 to 30 - Medium Dense 5 to 8 - Medium Stiff Some = 20 to 35%

31 to 50 - Dense 9 to 15 - Stiff And = 35 to 50%

SYMBOL KEY

0 to 4 - Very Loose 0 to 2 - Very Soft Trace = 0 to 10%

5 to 10 - Loose 3 to 4 - Soft Little = 10 to 20%

SPT N-Values SPT N-Values Proportions

Medium dense, red-brown, fine to coarse SAND, trace Silt S-6 5-5-6-6

S-5 6-6-5-5 Medium dense, red-brown, fine to coarse SAND, trace Silt

S-4 7-6-8-8 Medium dense, red-brown, fine to medium SAND, trace Silt

S-3 4-5-5-5 Loose, red-brown, fine to coarse SAND, trace Silt

S-2 4-4-5-4 Loose, brown/red-brown, fine to medium SAND, trace Silt

S-1 5-5-3-4 Loose, dark brown, fine to medium SAND, some Silt, trace (-) Roots

Type BLOWS PER Core Time

& No. 6 INCHES (min./ft)

3.25-inch I.D. Hollow-Stem Augers

SAMPLE INFORMATION SAMPLE DESCRIPTION STRATA

B-2

PROPOSED BUILDING ADDITIONS

81 FOURNIER STREET 0063-022.00

NEW HAVEN, CONNECTICUT DFL

Donut hammer driven by cathead with 30 inch drop

1-3/8" I.D. Split Spoon

Truck Mounted CME 55 10 - During drilling

Associated Borings Company Jaime Lloret Not Available Not Available

Mateusz Fekieta 5/26/2023 5/26/2023

0063-022.00 Boring Logs Page 2 of 2 Down to Earth Consulting, LLC

APPENDIX 3 -

LIMITATIONS

LIMITATIONS

Explorations

1. The analyses and recommendations submitted in this report are based in part upon the data obtained from subsurface explorations by others. The nature and extent of variations between these explorations may not become evident until construction. If variations then appear evident, it will be necessary to reevaluate the recommendations of this report.

2. The generalized soil profile described in the text is intended to convey trends in subsurface conditions.

The boundaries between strata are approximate and idealized and have been developed by interpretations of widely spaced explorations and samples; actual soil transitions are probably more erratic. For specific information, refer to the boring logs.

3. Water level readings have been made in the drill holes at times and under conditions stated on the boring logs. These data have been reviewed and interpretations have been made in the text of this report. However, it must be noted that fluctuations in the level of the groundwater may occur due to variations in rainfall, temperature, and other factors occurring since the time measurements were made.

Review

4. In the event that any changes in the nature, design or location of the proposed structure are planned, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and conclusions of this report modified or verified in writing by DTE. It is recommended that this firm be provided the opportunity for a general review of final design and specifications in order that earthwork and foundation recommendations may be properly interpreted and implemented in the design and specifications.

Construction

5. It is recommended that this firm be retained to provide soil engineering services during construction of the earthworks and foundation phases of the work. This is to observe compliance with the design concepts, specifications, and recommendations and to allow design changes in the event that subsurface conditions differ from those anticipated prior to start of construction.

Use of Report

6. This report has been prepared for the exclusive use of the City of New Haven, Connecticut for specific application to the project noted in this geotechnical report in accordance with generally accepted soil and foundation engineering practices. No other warranty, express or implied, is made.

7. This soil and foundation engineering report has been prepared for this project by DTE. This report is for design purposes only and is not sufficient to prepare an accurate bid. Contractors wishing a copy of the report may secure it with the understanding that its scope is limited to design considerations only.

8. This report may contain comparative cost estimates for the purpose of evaluating alternative foundation schemes. These estimates may also involve approximate quantity evaluations. It should be noted that quantity estimates may not be accurate enough for construction bids. Since DTE has no control over labor and materials cost and design, the estimates of construction costs have been made on the basis of experience. DTE does not guarantee the accuracy of cost estimates as compared to contractor's bids for construction costs.