Foundation Engineering Report

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FOUNDATION ENGINEERING REPORT

BABSON COLLEGE

HORN LIBRARY ADDITION PROJECT

BABSON PARK, MASSACHUSETTS

DECEMBER 4, 2017

Prepared For:

Babson College Facilities Management and Planning 231 Forest Street

2269 Massachusetts Avenue Babson Park, MA 02457 Cambridge, MA 02140 www.mcphailgeo.com (617) 868-1420

PROJECT NO. 6434

December 4, 2017

Babson College Facilities Management and Planning 231 Forest Street Babson Park, MA 02457

Attention: Ms. Vasso Mathes

Reference: Babson College Horn Library Addition Project; Babson Park, MA Foundation Engineering Report

Ladies and Gentlemen:

This report documents the results of our subsurface exploration program and foundation design study for the proposed Horn Library Addition Project to be located at Babson College in Babson Park, Massachusetts.

This report was prepared in accordance with our proposal dated July 10, 2017 and the subsequent authorization of Babson College. These services are subject to the limitations contained in Appendix A.

Purpose and Scope

The purposes of the subsurface exploration program and foundation design study are to assess the subsurface soil, rock and groundwater conditions at the site as they relate to foundation design and construction, and based on this information to provide safe and economic foundation design recommendations for the proposed addition.

Foundation design includes foundation support of the proposed structure and its lowest level slab, treatment of the lowest level slab in consideration of groundwater, and seismic design considerations in accordance with the provisions of the Eighth Edition of the Massachusetts State Building Code (Code). Foundation construction considerations relating to geotechnical aspects of the proposed construction are also presented herein.

Existing Site Conditions

The subject site fronts onto Babson College Drive to the northeast and is bounded by the Horn Library to the southwest, Babson Hall to the northwest, and Gerber Hall to the southeast. Currently, the site of the proposed development includes a brick and concrete patio area, grassed and landscaped areas, and walkways. Existing grades within the patio area are level at approximately Elevation +203. The patio area is up to 6 feet higher than the surrounding ground surface. Elevations slope down gradually from the northeastern edge of the patio to Babson College Drive which is at approximately Elevation +196.

GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERS 2269 Massachusetts Avenue Cambridge, Massachusetts 02140 (617) 868-1420

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The main floor of the existing Horn Library building is located at Elevation +208. It is understood that the existing building has a basement mechanical space that extends approximately 12 feet below the patio, which would correspond to Elevation +191. Structural drawings for the existing building have not been provided, but it is anticipated that foundation support is provided by spread footings bearing on the glacial till deposit.

Proposed Development

The proposed development is understood to consist of an approximate rectangular-shaped structure occupying a footprint of approximately 6,300 square feet that will be built as an addition to the Horn Library. The proposed design is still in preliminary stages, but it is currently anticipated that the addition will be 1 to 2 stories tall with no below-grade space. It is understood that the first floor of the addition will be located at approximately Elevation +196. Based on the existing site grades, the addition may be partially benched into the site slope.

Subsurface Exploration Program

On August 16 and 23, 2017, a subsurface exploration program consisting of three (3) borings was completed at the project site by McPhail Associates, LLC (McPhail). The borings were performed by Geosearch, Inc. of Fitchburg, Massachusetts under contract to McPhail. The approximate plan locations of the borings are included on the enclosed Subsurface Exploration Plan (Figure 2). Boring logs prepared by McPhail are included in Appendix B following the text of this report.

The borings were performed using a track-mounted drill-rig and advanced utilizing 4-1/4- inch diameter hollow-stem augers. Standard 2-inch O.D. split-spoon samples and standard penetration tests were generally obtained at minimum 5-foot intervals of depth in accordance with the standard procedures described in ASTM D1586. The borings were drilled to depths ranging from 17 to 22 feet below the ground surface, and were terminated within the natural glacial till deposit.

The borings were observed by a McPhail field representative who performed field layout, prepared field logs, obtained and visually classified soil samples, monitored groundwater conditions in the open explorations, and determined the required exploration depths based upon the actual subsurface conditions encountered.

Field locations of the borings were determined by taping from features included on a 40- scale drawing entitled “Progress Existing Conditions Plan” provided to us on September 5, 2017 and prepared by Vanasse Hangen Brustlin, Inc (VHB). The existing ground surface elevation at each exploration location was estimated based on vertical control information indicated on the referenced existing conditions plan.

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Laboratory Testing

At the completion of the field work, soil samples were returned to our laboratory for more detailed classification, analysis and testing. The laboratory testing consisted of sieve analyses to determine the gradations and confirm the visual classifications of the fill material and natural glacial till deposit. Laboratory test procedures were in general accordance with applicable ASTM Standards. Results of the sieve analyses for the fill material and natural glacial till deposit appear in Figures 3 and 4, respectively.

Subsurface Conditions

A detailed description of the subsurface conditions encountered in the borings is documented on the logs contained in Appendix B. Based on the explorations performed at the site, the following is a description of the generalized subsurface conditions across the site encountered from ground surface downward.

The ground surface across the existing patio area is typically covered with brick and concrete pavers. The borings were performed within landscaped areas located around the perimeter of the patio area. The landscaped areas contained approximately 6 inches of topsoil.

Underlying the surface treatments, a layer of fill material consisting of loose to very dense, brown sand and gravel, some silt, with trace roots, topsoil, and concrete was encountered. The fill material was observed to range from 7.5 to 9.8 feet in thickness within the patio area. Boring B-3 was performed outside the patio limits, and the fill material was observed to be only 3.5 feet thick at that location. Grain size distributions of typical samples of the fill material are presented on the enclosed Figure 3.

A glacial till deposit consisting of a dense to very dense, gray-brown to brown, silt and sand with some gravel varying to a well-graded mixture of silt, sand, and gravel was encountered below the fill material. Based on our past experience at the Babson College campus, the glacial till deposit is known to contain cobbles. The surface of the glacial till deposit was encountered at depths ranging from 4 to 11.3 feet below ground surface, or from approximately Elevation +193 to Elevation +191.7, respectively. The borings were terminated within the glacial till deposit at depths ranging from 15.8 to 22 feet below ground surface. Grain size distributions of typical samples of the glacial till deposit are presented on the enclosed Figure 4.

It is anticipated that the glacial till deposit is underlain by bedrock.

Groundwater was encountered within two (2) of the three (3) completed borings at depths ranging from 12 to 15 feet below ground surface, or from approximately Elevation +185 to Elevation +188, respectively. It is likely that groundwater is perched within the relatively impervious glacial till deposit and future groundwater levels across the site may vary from those reported herein due to factors such as normal seasonal changes, runoff particularly

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during or following periods of heavy precipitation, and alterations of existing drainage patterns.

Foundation Design Recommendations

Based on the scope of the proposed construction and the subsurface conditions encountered at the site, it is recommended that the proposed structure be founded on conventional spread footing foundations bearing directly on the undisturbed, natural glacial till deposit, or on compacted gravel fill placed over the surface of the natural deposit following the removal of all topsoil and/or fill material from within the proposed addition footprint. The plan limits of the placement of gravel fill for support of the proposed structure should extend laterally beyond the edges of the footings for a horizontal distance equal to the depth of overexcavation measured from the design bottom of footing elevation to the surface of the glacial till deposit, plus two feet.

Footings should be proportioned utilizing an allowable design bearing pressure of three (3) tons per square foot. The minimum footing width for perimeter footings and isolated footings should be 24 inches and 30 inches, respectively. All foundations should be designed in accordance with the Code.

Estimated long-term settlement for footings bearing on the natural glacial till deposit or compacted gravel fill is less than 1-inch and estimated long-term differential settlement of adjacent footings is less than 1/2-inch.

Perimeter foundations and interior foundations located below unheated areas should be provided with a minimum 4-foot thickness of soil cover as frost protection. Interior foundations founded below heated areas should be located such that the top of foundation concrete is a minimum of six inches below the underside of the lowest level slab.

Proposed footings to be located directly adjacent to existing foundations should be founded at the same elevation as the existing foundations. All other foundations should be located such that they bear below a theoretical line drawn upward and outward at 2 to 1 (horizontal to vertical) from the bottom exterior edge of all adjacent existing or proposed footings, structures and/or utilities.

It is recommended that the lowest level slab be designed as a conventional soil-supported slab-on-grade. The slab-on-grade should be underlain by a polyethylene vapor barrier spread across the surface of a minimum 9-inch thickness of compacted 3/4-inch crushed stone placed over a layer of filter fabric that is spread across the subgrade consisting of the undisturbed glacial till deposit. If existing fill material is encountered at the slab subgrade elevation, it should be removed from within the footprint of the proposed addition and replaced with compacted gravel fill.

All gravel fill placed within the footprint of the proposed addition should be placed in lifts having a compacted thickness of 6 inches and be compacted to a minimum of 95 percent of its maximum Modified Proctor dry density. The gravel fill should consist of a well-graded

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sand and gravel from a naturally-occurring source with less than eight percent passing the number 200 sieve.

It is recommended that perimeter and underslab drainage be provided wherever the proposed lowest level floor slab is more than 18 inches below the finished grade. The perimeter and underslab drains are intended to minimize groundwater intrusion into the below grade space due to conditions when groundwater may become temporarily elevated or “perched” within the glacial till deposit. The underslab and perimeter drainage systems are not intended to lower the existing groundwater level surrounding the site.

The perimeter and underslab drainage systems should consist of 4-inch diameter perforated PVC pipes having the highest invert a minimum of 12 inches below the underside of the lowest level slab. Where possible, the pipes should be pitched down at a minimum 0.5 percent slope in the direction of flow and be surrounded by a minimum 6-inch thickness of 3/4-inch crushed stone. The crushed stone around the perimeter drainage system should be surrounded by a thickness of filter fabric such as Mirafi 140N, or equivalent.

The perimeter and underslab drain lines should be gravity drained to a storm drain line that is not subject to surcharge or terminated within a sump pit that discharges into the storm drain system. If required, the sump pit should be equipped with duplex pumps, each of which should be capable of pumping a minimum of 30 gallons per minute against a 20-foot head.

All below-grade walls should receive a troweled-on bitumastic damproofing. A prefabricated drainage product, such as Miradrain 6000, should be installed directly against the below- grade perimeter foundation walls and be tied into the perimeter drainage system. Backfill against the perimeter foundation walls may consist of ordinary fill. Additionally, the exterior site grades should be sloped away from the perimeter of the proposed addition to minimize surface water infiltration.

All localized depressions in the lowest level slabs, such as elevator pits, should be provided with properly tied continuous waterstops in all construction joints and metallic waterproofing should be applied to properly prepared interior surfaces to protect against groundwater intrusion.

Below-grade foundation walls receiving lateral support at the top and bottom (i.e. restrained walls) should be designed for a lateral earth pressure corresponding to an equivalent fluid density of 60 pounds per cubic foot. To these values must be added the pressures attributable to earthquake forces per Section 1610.2 of the Code.

Lateral forces can be transmitted from the structure to the soil by passive pressure on the footings utilizing an equivalent fluid density of 120 pounds per cubic-foot providing that these structural elements are designed to resist these pressures. Lateral forces can also be considered to be transmitted from the structure to the soil by friction on the base of the footings using a frictional coefficient of 0.50 to which a factor of safety of 1.5 should be applied.

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Seismic Design Considerations

For the purposes of determining parameters for structural seismic design, this site is considered to be a Site Class C as defined in Section 1613.5.5 of the Code. Further, the bearing strata on the proposed site are not considered to be subject to liquefaction during an earthquake based on the criterion of Section 1806.4 of the Code.

Foundation Construction Considerations

The primary construction considerations include preparation of the foundation bearing surfaces, subgrade protection, removal of foundation remains of existing structures, relocation of existing utilities, construction dewatering, and reuse of on-site soils.

The final excavation of the footing subgrade should be accomplished using an excavator that is equipped with smooth-edged bucket to avoid disturbance of the bearing surface. Further, it is recommended that as soon as the bearing surface is exposed, it be immediately covered with a minimum 3-inch thickness of compacted 3/4-inch crushed stone to prevent disturbance of the subgrade during subsequent forming operations.

The existing patio currently occupying the project site will be partially demolished as a result of the planned development. The existing foundations may remain in place where they don’t interfere with the proposed development provided that they are removed to a depth of 24 inches beneath the proposed finished grade or slab elevation.

Where existing utilities and structures are located within the footprint of the proposed addition, they should be relocated prior to construction. The resulting abandoned utility/structure and associated backfill should be removed and replaced with compacted gravel fill.

Due to the moderate to high silt content of the natural glacial till deposit, proper control of groundwater and surface water will be necessary to maintain a firm subgrade to support construction traffic. Based on the soil and groundwater conditions encountered in the subsurface explorations, it is anticipated that groundwater and surface water can be controlled using conventional sumping. Pumped groundwater should be recharged on-site where possible. Otherwise, the appropriate dewatering discharge permits should be obtained prior to discharging water into nearby storm drains. Even with proper control of both surface water and groundwater, it is probable that during periods of wet weather off- site gravel fill and/or crushed stone may be required to maintain trafficability for construction equipment.

Due to the moderate to high silt content of the existing glacial till deposit, these soils are not anticipated to be suitable for reuse on-site. However, the existing fill material is anticipated to be suitable for reuse as ordinary fill, provided that it is maintained in a relatively dry condition and can be properly compacted.

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As indicated above, the existing fill material contains a moderate silt content. Hence, it is emphasized that this excavated soil can become unsuitable for reuse as ordinary fill if it becomes too wet. It is recommended that stockpiles of excavated material intended for reuse be protected against increases in moisture content by securely covering the stockpiles prior to and during precipitation events. Therefore, the placement and compaction of the on-site soil should be completed during relatively dry and non-freezing conditions.

Current Department of Environmental Protection (DEP) policies and regulations for off-site disposal of excess excavated soil require environmental characterization of the excess excavated soil prior to its off-site disposal. In general, one full suite of chemical analyses per 500 cubic yards of topsoil and/or fill material, and one full suite of chemical testing per 1,000 cubic yards of natural glacial till material is typically required by the receiving facilities. Therefore, based on the actual volume of soil that is required to be removed from the site, some chemical testing of soil samples may be required for the off-site disposal of excess excavated soil. McPhail Associates, LLC can provide these services should they be required for this project.

Final Comments

It is recommended that McPhail Associates, LLC be retained to provide design assistance to the design team during the final design phase of this project. The purpose of this involvement would be to review the structural foundation drawings and foundation notes for conformance with the recommendations presented herein and to prepare the earthwork specification section for inclusion into the Contract Documents for construction.

It is also recommended that McPhail Associates, LLC be retained during the construction period to observe final preparation of the foundation bearing surfaces and to monitor placement and compaction of fill materials in accordance with the provisions of the Code and the provisions of the Contract Documents. Our involvement during the construction phase of the work should minimize costly delays due to unanticipated field problems since our field engineer would be under the direct supervision of our project manager who was responsible for the subsurface exploration program and foundation design recommendations documented herein.

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We trust that the above is sufficient for your present requirements. Should you have any questions concerning the recommendations presented herein, please do not hesitate to contact us.

Very truly yours,

McPHAIL ASSOCIATES, LLC

Benjamin E. Downing, P.E. Chris M. Erikson, P.E.

N:\Working Documents\Reports\6434 FER rev1 120417.docx

BED/cme

FIGURE 1

SITE

PROJECT LOCATION PLAN BABSON COLLEGE HORN COLLIDER PROJECT

BABSON PARK MASSACHUSETTS SCALE 1:25,000 FIGURE 2

NORTH

B-1

B-3 B-2

APPROXIMATE LIMITS OF PROPOSED ADDITION

BABSON COLLEGE DRIVE

BABSON COLLEGE HORN COLLIDER PROJECT LEGEND BABSON PARK MASSACHUSETTS SUBSURFACE EXPLORATION PLAN APPROXIMATE LOCATION OF BORING PERFORMED BY GEOSEARCH, INC. ON FOR AUGUST 17 AND AUGUST 23, 2017 FOR McPHAIL ASSOCIATES, LLC BABSON COLLEGE

N:\Acad\JOBS\6434\6434-F02.dwg BY REFERENCE: THIS PLAN WAS PREPARED FROM A 40-SCALE DRAWING ENTITLED, "PROGRESS GRAPHIC SCALE McPHAIL ASSOCIATES, LLC EXISTING CONDITIONS PLAN" DATED SEPTEMBER 5, 2017 PREPARED BY VHB 50 0 50 100 2269 Massachusetts Avenue Cambridge, MA 02140

FILE NAME: 617/868-1420 Date: SEPTEMBER 2017 Dwn: M.B.S. Chkd: B.E.D. Scale: 1" = 50' 617/868-1423 (Fax) 6434 www.mcphailgeo.com Project No: FILE NAME: N:\Working Documents\Jobs\6434\Excel\6406_FO3_Fill_090717.xls PROJECT No. 6434

M.I.T. GRAIN SIZE SCALE

Size of opening, inches U.S.S. Sieve size, meshes/inch

6" 3" 1½" 3/4" 3/8" 4 10 20 40 60 100 200 100

90 LEGEND GRAIN SIZE DISTRIBUTIONGRAIN SIZE

80 B-1 S-2 5'-7' McPHAIL ASSOCIATES, LLC ASSOCIATES, McPHAIL

70 FILL MATERIAL B-2 S-3 4'-6'

40 PERCENT FINER THAN FINER PERCENT

10 FIGURE 0 100 10 1 0.1 0.01 0.001 0.0001

GRAIN SIZE, MM

COBBLE COARSE MEDIUM FINE COARSE MEDIUM FINE SILT SIZE CLAY SIZE 3 SIZE GRAVEL SIZE SAND SIZE FINE GRAINED FILE NAME: N:\Working Documents\Jobs\6434\Excel\6406_FO4_Glacial_Till_090617.xls PROJECT No. 6434

M.I.T. GRAIN SIZE SCALE

Size of opening, inches U.S.S. Sieve size, meshes/inch

6" 3" 1½" 3/4" 3/8" 4 10 20 40 60 100 200 100

90 LEGEND GRAIN SIZE DISTRIBUTIONGRAIN SIZE 80

B-1 S-4 15'-17' GLACIAL TILL DEPOSIT McPHAIL ASSOCIATES, LLC ASSOCIATES, McPHAIL

70 B-3 S-3 4'-6'

40 PERCENT FINER THAN FINER PERCENT

10 FIGURE 0 100 10 1 0.1 0.01 0.001 0.0001

GRAIN SIZE, MM

COBBLE COARSE MEDIUM FINE COARSE MEDIUM FINE SILT SIZE CLAY SIZE 4 SIZE GRAVEL SIZE SAND SIZE FINE GRAINED

APPENDIX A:

LIMITATIONS

This report has been prepared on behalf of and for the exclusive use of Babson College for specific application to the proposed Horn Library Addition Project to be located at Babson College in Babson Park, Massachusetts in accordance with generally accepted soil and geotechnical engineering practices. No other warranty, expressed or implied, is made.

In the event that any changes in nature or design of the proposed construction are planned, the conclusions and recommendations contained in this report should not be considered valid unless the changes are reviewed and conclusions of this report modified or verified in writing by McPhail Associates.

The analyses and recommendations presented in this report are based upon the data obtained from the subsurface explorations performed at the approximate locations indicated on the enclosed plan. If variations in the nature and extent of subsurface conditions between the widely spaced explorations become evident during the course of construction, it will be necessary for a re-evaluation of the recommendations of this report to be made after performing on-site observations during the construction period and noting the characteristics of any variations.

APPENDIX B:

BORING LOGS PREPARED BY MCPHAIL ASSOCIATES, LLC

Project: Babson College Job #: 6434 Boring No. Location: Babson Campus Date Started: 8-16-17 City/State: Wellesley, MA Date Finished: 8-16-17 B-1 Groundwater Observations Contractor: Casing Type: Geosearch 4.25" Date Depth Elev. Notes Driller/Helper: N/A Casing Hammer (lbs)/Drop (in): N/A Logged By/Reviewed By: C. Foley Sampler Size/Type: 24" Split Spoon Surface Elevation (ft): 203.0 Sampler Hammer (lbs)/Drop (in): 140lb/30" Sample Depth Elev. Sample Description

(ft) Stratum N-Value Pen. Depth Blows/6" (ft) (ft) No. /Rec. and Boring Notes Symbol Depth/EL to RQD (in) (ft) Min/ft Strata Change 0.5 / 202.5 TOPSOIL 3 Compact, brown, SAND and GRAVEL, some silt, trace roots. (Fill) 1 202 25 S1 24/12 0.0-2.0 10 15 2 201 16

3 200

4 199

5 198 21 Dense, brown, SAND and GRAVEL, some silt. (Fill) 29 6 197 FILL 42 S2 24/14 5.0-7.0 13 7 196 8

8 195

9 194

10 193 21 Very dense, brown, SAND and GRAVEL, some silt, w/ concrete. (Fill) 138/9" S3 15/12 10.0-11.3 38 11 192 11.3 / 191.7 100/3" 12 191

13 190

14 189

15 188 31 Very dense, brown, SILT and SAND, some gravel. (Glacial Till) 16 187 96 S4 22/16 15.0-16.8 42 54 GLACIAL TILL 17 186 100/4"

18 185

19 184

20 183 21 Very dense, brown, SILT and SAND, some gravel. (Glacial Till) 21 182 83 S5 24/18 20.0-22.0 34 49 22 181 22.0 / 181.0 51 Bottom of borehole 22 feet below 23 180 ground surface.

24 179

GRANULAR SOILS SOIL COMPONENT BLOWS/FT. DENSITY 0-4 V.LOOSE DESCRIPTIVE TERM PROPORTION OF TOTAL SOIL CONTAINING THREE 4-10 LOOSE COMPONENTS EACH OF WHICH 10-30 COMPACT "TRACE" 0-10% COMPRISE AT LEAST 25% OF 30-50 DENSE "SOME" 10-20% THE TOTAL ARE CLASSIFIED AS "ADJECTIVE" (eg SANDY, SILTY) 20-35% "A WELL-GRADED MIXTURE OF" >50 V.DENSE "AND" 35-50% COHESIVE SOILS McPHAIL ASSOCIATES, LLC BLOWS/FT. CONSISTENCY Notes: 2269 MASSACHUSETTS AVENUE <2 V.SOFT No observed groundwater. CAMBRIDGE, MA 02140 2-4 SOFT TEL: 617-868-1420 FAX: 617-868-1423 4-8 FIRM 8-15 STIFF 15-30 V.STIFF Page 1 of 1 >30 HARD Weather: Sunny Project: Babson College Job #: 6434 Boring No. Location: Babson Campus Date Started: 8-23-17 City/State: Wellesley, MA Date Finished: 8-23-17 B-2 Groundwater Observations Contractor: Casing Type: Geosearch 4.25" Date Depth Elev. Notes Driller/Helper: Joe/Josh/Sean Casing Hammer (lbs)/Drop (in): N/A 8-23-17 15 188.0 Logged By/Reviewed By: L. Pacheco Sampler Size/Type: 24" Split Spoon Surface Elevation (ft): 203.0 Sampler Hammer (lbs)/Drop (in): 140lb/30" Sample Depth Elev. Sample Description

(ft) Stratum N-Value Pen. Depth Blows/6" (ft) (ft) No. /Rec. and Boring Notes Symbol Depth/EL to RQD (in) (ft) Min/ft Strata Change 0.5 / 202.5 TOPSOIL 2 Lose, brown, SAND and GRAVEL, some silt, trace roots. (Fill) 1 202 9 S1 24/10 0.0-2.0 2 7 2 201 14 22 Dense, brown to light brown, SAND and GRAVEL, some silt. (Fill) 3 200 49 S2 24/1 2.0-4.0 22 27 4 199 14 FILL 11 Compact, dark brown, SAND and GRAVEL, some silt. (Fill) 10 5 198 20 S3 24/1 4.0-6.0 10 6 197 6 6 NO RECOVERY 9 7 196 21 S4 24/0 6.0-8.0 12 8 195 8.0 / 195.0 18 24 Very dense, light brown to gray, SILT and SAND, some gravel. 30 (Glacial Till) 9 194 64 S5 24/14 8.0-10.0 34 10 193 43

11 192

12 191 GLACIAL TILL 13 190

14 189

15 188 7 Dense, light brown to gray, well graded mixture of, SILT, SAND and GRAVEL. (Glacial Till) 16 187 39 S6 24/11 15.0-17.0 19 20 17 186 17.0 / 186.0 25 Bottom of borehole 17 feet below 18 185 ground surface.

19 184

20 183

21 182

22 181

23 180

24 179

GRANULAR SOILS SOIL COMPONENT BLOWS/FT. DENSITY 0-4 V.LOOSE DESCRIPTIVE TERM PROPORTION OF TOTAL SOIL CONTAINING THREE 4-10 LOOSE COMPONENTS EACH OF WHICH 10-30 COMPACT "TRACE" 0-10% COMPRISE AT LEAST 25% OF 30-50 DENSE "SOME" 10-20% THE TOTAL ARE CLASSIFIED AS "ADJECTIVE" (eg SANDY, SILTY) 20-35% "A WELL-GRADED MIXTURE OF" >50 V.DENSE "AND" 35-50% COHESIVE SOILS McPHAIL ASSOCIATES, LLC BLOWS/FT. CONSISTENCY Notes: 2269 MASSACHUSETTS AVENUE <2 V.SOFT CAMBRIDGE, MA 02140 2-4 SOFT TEL: 617-868-1420 FAX: 617-868-1423 4-8 FIRM 8-15 STIFF 15-30 V.STIFF Page 1 of 1 >30 HARD Weather: Sunny Project: Babson College Job #: 6434 Boring No. Location: Babson Campus Date Started: 8-23-17 City/State: Wellesley, MA Date Finished: 8-23-17 B-3 Groundwater Observations Contractor: Casing Type: Geosearch 4.25" Date Depth Elev. Notes Driller/Helper: Joe/Josh/Sean Casing Hammer (lbs)/Drop (in): N/A 8-23-17 12 185.0 Logged By/Reviewed By: L. Pacheco Sampler Size/Type: 24" Split Spoon Surface Elevation (ft): 197.0 Sampler Hammer (lbs)/Drop (in): 140lb/30" Sample Depth Elev. Sample Description

(ft) Stratum N-Value Pen. Depth Blows/6" (ft) (ft) No. /Rec. and Boring Notes Symbol Depth/EL to RQD (in) (ft) Min/ft Strata Change 0.5 / 196.5 TOPSOIL 4 Compact, brown to light brown, SAND and GRAVEL, some silt, trace roots. (Fill) 1 196 26 S1 24/12 0.0-2.0 5 21 2 195 35 FILL 22 Very dense, light brown to dark brown, SAND and GRAVEL, some silt, trace roots. (Fill) 3 194 57 S2 24/10 2.0-4.0 30 27 4 193 4.0 / 193.0 40 13 Very dense, dark brown to light brown, well graded mixture of, SILT, 145/11" S3 17/12 4.0-5.4 SAND and GRAVEL. (Glacial Till) 5 192 45 100/5" 6 191

7 190

8 189

9 188

10 187 GLACIAL TILL 14 Very dense, dark brown to light brown/gray, well graded mixture of, 24 SILT, SAND and GRAVEL. (Glacial Till) 11 186 56 S4 24/14 10.0-12.0 32 12 185 28

13 184

14 183

15 182 176/9" S5 9/6 15.0-15.8 76 Very dense, light brown/gray, SILT and SAND, some gravel. (Glacial 15.8 / 181.2 100/3" Till) 16 181 Bottom of borehole 15.8 feet below ground surface. 17 180

18 179

19 178

20 177

21 176

22 175

23 174

24 173