ATT-PFMD-062226-16-Geotechnical Report-SHR Aviation Flight Line Pavement Repl.pdf

LIMITED GEOTECHNICAL

INVESTIGATION

PROPOSED SHR AVIATION FLIGHT LINE PAVEMENT

REPLACEMENT PROJECT

SBC PROJECT NO.: WBSE 10.10.1932

SHERIFF’S DEPARTMENT EMERGENCY OPERATIONS

FACILITY AT SAN BERNARDINO

INTERNATIONAL AIRPORT

199 HANGAR WAY

SAN BERNARDINO, CALIFORNIA

NOVEMBER 10, 2025

PROJECT NO. W1755‐99‐07

PREPARED FOR:

San Bernardino County

Project and Facilities Management Department

San Bernardino, California

500 N Victory Boulevard ■ Burbank, CA 91502 ■ Telephone 818.841.8388 ■ Fax 818.841.1704

Project No. W1755‐99‐07 November 10, 2025

San Bernardino County Project and Facilities Management Department 620 South E Street San Bernardino, CA 92415

Attention: Elsy Banks, Project Manager III

Subject: LIMITED GEOTECHNICAL INVESTIGATION

PROPOSED SHR FLIGHT LINE PAVEMENT REPLACEMENT PROJECT

SBC PROJECT NO.: 10.10.1932

SHERIFF’S DEPARTMENT EMERGENCY OPERATIONS FACILITY AT

SAN BERNARDINO INTERNATIONAL AIRPORT

199 HANGAR WAY, SAN BERNARDINO, CALIFORNIA

Dear Esly Banks:

In accordance with your authorization of our proposal dated August 19, 2025, we have performed a limited geotechnical investigation for the proposed SHR Flight Line Pavement Replacement Project located at the Sheriff’s Department Emergency Operations Facility at the San Bernardino International

Airport. The accompanying report presents the findings of our study and our conclusions and recommendations pertaining to the geotechnical aspects of the proposed design and construction.

Based on the results of our investigation, it is our opinion that the improvements can be constructed as proposed, provided the recommendations of this report are followed and implemented during design and construction.

If you have any questions regarding this report or if we may be of further service, please contact the undersigned.

Very truly yours, GEOCON WEST, INC.

Michael A. Cazeneuve

GE 3114 / CEG 2546

Neal D. Berliner

GE 2576

(email) Addressee

SHR Flight Line Pavement Replacement Project

Limited Geotechnical Investigation

TABLE OF CONTENTS

1. PURPOSE AND SCOPE

2. SITE AND PROJECT DESCRIPTION

3. SOIL AND GEOLOGIC CONDITIONS

3.1 Artificial Fill

3.2 Younger Alluvium

4. GROUNDWATER

5. CONCLUSIONS AND RECOMMENDATIONS

5.1 General

5.2 Soil and Excavation Characteristics

5.3 Water‐Soluble Sulfate

5.4 Grading – Paving Subgrade Preparation

5.5 Concrete Pavement Recommendations

5.6 Temporary Excavations

5.7 Stormwater Infiltration

5.8 Surface Drainage

5.9 Plan Review

LIMITATIONS AND UNIFORMITY OF CONDITIONS

LIST OF REFERENCES

MAPS AND ILLUSTRATIONS

Figure 1, Vicinity Map Figure 2, Site Plan Figure 3 through 6, Percolation Test Results

APPENDIX A

FIELD INVESTIGATION

Figures A1 through A10, Boring Logs

APPENDIX B

LABORATORY TESTING

Figures B1 through B3, Grain Size Distribution

Figures B4 and B5, R‐Value Test Results

Figures B6 and B7, Compaction Characteristics Using Modified Effort Test Results

Figure B8, Corrosivity Test Results

APPENDIX C

FAARFIELD 2.1 STRUCTURE REPORT

Project No. W1755‐99‐07 ‐ 1 ‐ November 10, 2025

LIMITED GEOTECHNICAL INVESTIGATION

1. PURPOSE AND SCOPE

This report presents the results of a limited geotechnical investigation for the proposed SHR Flight Line

Pavement Replacement Project located at the Sheriff’s Department Emergency Operations Facility at the San Bernardino International Airport (see Vicinity Map, Figure 1). The purpose of the investigation was to evaluate subsurface soil and geologic conditions underlying the site and, based on conditions encountered, to provide conclusions and recommendations pertaining to the geotechnical aspects of proposed design and construction.

The scope of this investigation included a site reconnaissance, field exploration, laboratory testing, engineering analysis, and the preparation of this report. The site was explored on October 3, 2025, by excavating ten 8‐inch‐diameter borings using a truck‐mounted hollow‐stem auger drilling machine to a maximum depth of approximately 20½ feet beneath the ground surface. The approximate locations of the exploratory borings are depicted on the Site Plan (see Figure 2). A detailed discussion of the field investigation, including boring logs, is presented in Appendix A.

Laboratory tests were performed on selected soil samples obtained during the investigation to determine pertinent physical and chemical soil properties. Appendix B presents a summary of the laboratory test results.

The recommendations presented herein are based on analysis of the data obtained during the investigation and our experience with similar soil and geologic conditions. References reviewed to prepare this report are provided in the List of References section.

If project details vary significantly from those described herein, Geocon should be contacted to determine the necessity for review and possible revision of this report.

2. SITE AND PROJECT DESCRIPTION

The subject site is located at 199 Hangar Way, in the city of San Bernardino, California. It is situated in the northern portion of the San Bernardino International Airport property. The existing facility consists of a single‐story maintenance hangar, storage hangar, administration building, asphalt‐paved parking and flightline areas, and concrete landing pads for helicopters. The site is bounded to the south, east, and west by the operational airport infrastructure, including paved flightline areas and hangar‐type structures. It is bounded to the north by an unpaved and undeveloped yard that appears to be utilized for shipping container storage.

Project No. W1755‐99‐07 ‐ 2 ‐ November 10, 2025

The site is relatively level and very gently descends to the west with surface elevations ranging between approximately 1,139 and 1,135 feet above mean sea level (MSL). Surface drainage at the site appears to occur by sheetflow to storm drains and the city streets. Vegetation on the site is predominantly non‐ existent, with the exception of some small trees and bushes in planter areas around the parking lot for the administration building on the north end of the site. The existing facility is shown in Figure 2.

Based on the information provided by the Client, we understand the proposed project includes the complete removal of the existing asphalt pavements and replacement with new Portland Cement

Concrete (PCC). The existing concrete landing pads may or may not be replaced as part of the project.

In addition, stormwater infiltration facilities are under consideration for the proposed project.

We understand that a fleet of helicopters and fixed‐wing aircraft will operate out of the facility.

According to the client, the number of aircraft, make and model, and number of anticipated operations per year (i.e. takeoffs and landings) are shown in the tables below. It is assumed that other ground support vehicles will also utilize the pavements. Earthwork for the project is expected to include subgrade preparations, excavation, and compaction of the upper site soils.

ROTARY AIRCRAFT (HELICOPTERS)

Aircraft Make and Model

Number of Aircraft Type

Number of Operations per Year per Aircraft

Total Number of Operations per Year

Bell 412EPX 2 700 1,400

Bell 212 1 Not Provided

Bell UH‐1H 1 Not Provided

Airbus AS350B3 7 3,650 25,550

FIXED WING AIRCRAFT

Aircraft Make and Model

Number of Aircraft Type

Number of Operations per Year per Aircraft

Total Number of Operations per Year

Beechcraft King Air

1 50 50

Beechcraft King Air

2 25 50

Mahindra / GippsAero GA8 Airvan

2 200 400

Should more detailed information regarding the aerial fleet and ground support vehicles become available, the recommendations within this report should be reviewed and revised, if necessary.

Any changes in the design, location, or elevation of any improvement, as outlined in this report, should be reviewed by this office. Geocon should be contacted to determine the necessity for review and possible revision of this report.

Project No. W1755‐99‐07 ‐ 3 ‐ November 10, 2025

3. SOIL AND GEOLOGIC CONDITIONS

Based on our field investigation and published geologic maps of the area, the site is underlain by artificial fill and Holocene alluvial deposits (California Geological Survey, 2010). Detailed stratigraphic profiles of the materials encountered at the site are provided on the boring logs in Appendix A.

3.1 Artificial Fill

Artificial fill was encountered in our explorations to a maximum depth of 6 feet below the existing ground surface. The artificial fill generally consists of brown to grayish brown silty sand and sand that can be characterized as slightly moist, medium dense, predominantly fine grained, and occasionally medium to coarse grained, with minor amounts of gravel and occasional cobbles. The fill is likely the result of past grading or construction activities at the site. Deeper fill may exist between excavations and in other portions of the site that were not directly explored.

3.2 Younger Alluvium

Holocene‐age alluvium was encountered beneath the fill in each boring to the maximum depth explored of 20½ feet below the existing ground surface. The alluvium generally consists of brown to grayish brown silty sand and poorly graded sand. The alluvial soils are characterized as slightly moist and loose to dense, with minor gravels and occasional cobbles.

4. GROUNDWATER

Groundwater level information for the site vicinity was obtained from Carson and Matti (1985), and the

California Department of Water Resources (CDWR) Water Data Library (WDL).

Data from the CDWR indicates the two groundwater monitoring wells are located to the north and northwest of the site. State Well No. 01S03WC5N006S is located approximately 0.3 miles north of the site (CDWR, 2025). Groundwater level data for this well was available for the monitoring period between 1987 and 1988. Based on the available data, the depth to groundwater has been greater than

66 feet below the existing ground surface for the reported monitoring period. Similarly, State Well No.

01S03W06P006S is located approximately 0.5 miles northwest of the site. The depth to groundwater in this well between 2005 and 2008 has been greater than approximately 150 feet below the ground surface. Groundwater data provided in (Carson and Matti, 1985) indicate high groundwater levels on the order of 100 to 150 feet below the ground surface.

Project No. W1755‐99‐07 ‐ 4 ‐ November 10, 2025

Groundwater was not encountered in our field explorations, drilled to a maximum depth of 20½ feet below the existing ground surface. Based on the historic groundwater levels in the site vicinity (CDWR, 2025; Carson and Matti, 1985), the lack of groundwater encountered in our borings, and the depth of proposed construction, static groundwater is neither expected to be encountered during construction nor to have a detrimental effect on the project. However, it is not uncommon for groundwater levels to vary seasonally or for groundwater seepage conditions to develop where none previously existed, especially in impermeable fine‐grained soils which are heavily irrigated or after seasonal rainfall.

In addition, recent requirements for stormwater infiltration could result in shallower seepage conditions in the immediate site vicinity. Proper surface drainage of irrigation and precipitation will be critical for future performance of the project. Recommendations for drainage are provided in the

Surface Drainage section of this report (see Section 5.8).

Project No. W1755‐99‐07 ‐ 5 ‐ November 10, 2025

5. CONCLUSIONS AND RECOMMENDATIONS

5.1 General

5.1.1 It is our opinion that neither soil nor geologic conditions were encountered during the investigation that would preclude the construction of the proposed improvements, provided the recommendations presented herein are followed and implemented during design and construction.

5.1.2 Up to 6 feet of existing artificial fill was encountered during the site investigation. The existing fill encountered is believed to be the result of past grading and construction activities at the site. Natural alluvial soils were encountered below the existing artificial fill.The existing fill and alluvial soils predominantly consist of silty sands and sands, which are suitable for re‐use as engineered fill provided the recommendations in the Grading section of this report are followed (see Section 5.4).

5.1.3 Where new concrete pavement is to be placed, it is recommended that the upper fill soils and alluvial soils be scarified and properly compacted for paving support. Subgrades supporting the proposed pavements should be prepared in accordance with Section 5.4.

5.1.4 Recommendations for concrete paving sections are provided in Section 5.5. All pavements and related earthwork for the project shall be designed and constructed in accordance with

Federal Aviation Administration (FAA) Advisory Circulars 150/5320‐6G, 150/5335‐5D, 150/5370‐10H, and 150/5390‐2D.

5.1.5 Based on the results of percolation testing performed at the site, a stormwater infiltration system is considered feasible for this project. Recommendations for infiltration are provided in the Stormwater Infiltration section of this report (see Section 5.7).

5.1.6 Once the design and configuration for the proposed improvements proceed to a more finalized plan, the recommendations within this report should be reviewed and revised, if necessary. Any changes in the design, location, or elevation, as outlined in this report, should be reviewed by this office. Geocon should be contacted to determine the necessity for review and possible revision of this report.

Project No. W1755‐99‐07 ‐ 6 ‐ November 10, 2025

5.2 Soil and Excavation Characteristics

5.2.1 The in‐situ soils can be excavated with moderate effort using conventional excavation equipment. Some caving should be anticipated in unshored excavations, especially where granular soils are encountered.

5.2.2 It is the responsibility of the contractor to ensure that all excavations and trenches are properly shored and maintained in accordance with applicable OSHA rules and regulations to maintain safety and maintain the stability of existing adjacent improvements.

5.2.3 All onsite excavations must be conducted in such a manner that potential surcharges from existing structures, construction equipment, and vehicle loads are resisted. The surcharge area may be defined by a 1:1 projection down and away from the bottom of an existing foundation or vehicle load. Penetrations below this 1:1 projection will require special excavation measures such as sloping or shoring. Excavation recommendations are provided in the Temporary Excavations section of this report (see Section 5.6).

5.2.4 Based on the granular nature of the soils encountered during exploration, the site soils are considered to have a “very low” expansive potential and are classified as “non‐expansive” in accordance with the 2022 California Building Code (CBC) Section 1803.5.3.

The recommendations presented herein assume that pavements will derive support from these materials.

5.3 Water‐Soluble Sulfate

5.3.1 Laboratory tests were performed on representative samples of the on‐site soil to measure the percentage of water‐soluble sulfate content. Results from the laboratory water‐soluble sulfate tests are presented in Appendix B (Figure B8) and indicate that the on‐site soil possesses a sulfate exposure class of “S0” to concrete structures as defined by 2022 CBC

Section 1904A and ACI 318‐19 Chapter 19.

5.3.2 Geocon West, Inc. does not practice in the field of corrosion engineering and mitigation.

If corrosion‐sensitive improvements are planned, it is recommended that a corrosion engineer be retained to evaluate corrosion test results and incorporate the necessary precautions to avoid premature corrosion of buried metal pipes and concrete structures in direct contact with the soils.

Project No. W1755‐99‐07 ‐ 7 ‐ November 10, 2025

5.4 Grading – Paving Subgrade Preparation

5.4.1 A preconstruction conference should be held at the site prior to the beginning of grading operations, with the owner, contractor, civil engineer, geotechnical engineer, and building official in attendance. Special soil handling requirements can be discussed at that time.

5.4.2 Earthwork should be observed, and compacted fill should be tested by representatives of

Geocon West, Inc. The existing fill and alluvial soil encountered during exploration are suitable for re‐use as an engineered fill, provided that any encountered oversize material

(greater than 6 inches) and any encountered deleterious debris are removed.

5.4.3 Subgrade preparation should commence with the removal of all existing vegetation and existing improvements from the area to be graded. Deleterious debris, such as wood and root structures, should be exported from the site and should not be mixed with the fill soils.

Asphalt and concrete should not be mixed with the fill soils unless approved by the

Geotechnical Engineer. All existing underground improvements planned for removal should be completely excavated and the resulting depressions properly backfilled in accordance with the procedures described herein. Once a clean excavation bottom has been established, it must be observed and approved in writing by the Geotechnical Engineer (a representative of

Geocon West, Inc.).

5.4.4. In accordance with FAA AC 150/5370‐10H, Section 152‐2.5, it is recommended that the upper

12 inches of soil that will support new concrete pavement sections be scarified, moisture conditioned to optimum moisture content, and compacted to 95 percent of the maximum density, as determined by ASTM D 1557 (latest edition). The 95 percent compaction requirement assumes the proposed pavements will not support aircraft and/or vehicles with gross weights greater than 60,000 pounds. A relative compaction of 100 percent will be required if the proposed pavements will support traffic with gross weights greater than

60,000 pounds.

5.4.5. Deeper excavations should be conducted as necessary to remove unsuitable fill, soft soils, or otherwise unsuitable materials. The limits of the removal shall be verified by a representative of Geocon during site grading.

5.4.6 All excavations must be observed and approved in writing by the Geotechnical Engineer

(a representative of Geocon). Prior to placing any fill, the exposed subgrade must be proof‐rolled with heavy equipment in the presence of the Geotechnical Engineer (a representative of Geocon West, Inc.).

Project No. W1755‐99‐07 ‐ 8 ‐ November 10, 2025

5.4.7 All fill and backfill soils should be placed in horizontal loose layers approximately 6 to

8 inches thick, moisture conditioned to optimum moisture content, and properly compacted to a minimum of 95 percent of the maximum dry density in accordance with ASTM D 1557

(latest edition). In accordance with FAA AC 150/5370‐10H, Section 152‐2.5, soils in the upper

12 inches of subgrade shall be compacted to 95 percent of the maximum dry density in accordance with ASTM D 1557 (latest edition). The 95 percent compaction requirement assumes the proposed pavements will not support aircraft and/or vehicles with gross weights greater than 60,000 pounds. A relative compaction of 100 percent will be required if the proposed pavements will support traffic with gross weights greater than 60,000 pounds.

5.4.8 Any imported fill shall be observed, tested, and approved by Geocon West, Inc. prior to bringing soil to the site. Import fill should consist of the characteristics presented in the table below.

SUMMARY OF IMPORT FILL RECOMMENDATIONS

Soil Characteristic Values

Expansion Potential “Very Low” (Expansion Index of 20 or less)

Particle Size Maximum Dimension Less Than 6 Inches

Free of Debris

Corrosivity Less Detrimental Than Existing Onsite Soils

5.4.9 All subgrades must be observed and approved in writing by the Geotechnical Engineer

(a representative of Geocon) prior to placing fill, aggregate base, or concrete.

5.5 Concrete Pavement Recommendations

5.5.1 Where new concrete paving is to be placed, it is recommended that the upper fill and alluvial soils be scarified and properly compacted for paving support. As a minimum, the upper

12 inches of paving subgrade should be scarified, moisture conditioned to near optimum moisture content, and properly compacted to 95 percent relative compaction, as determined by ASTM Test Method D 1557 (latest edition). The 95 percent compaction requirement assumes the proposed pavements will not support aircraft and/or vehicles with gross weights greater than 60,000 pounds. A relative compaction of 100 percent will be required if the proposed pavements will support traffic with gross weights greater than 60,000 pounds.

Project No. W1755‐99‐07 ‐ 9 ‐ November 10, 2025

5.5.2 Concrete pavement sections have been developed utilizing the FAA pavement design software FAARFIELD version 2.1.1, and the aircraft fleet information provided by the client.

A 20‐year design life was assumed in the analysis. Where available, aircraft specifications were utilized from the FAARFIELD Aircraft Library. However, the library does not include data for helicopters. Therefore, user‐defined aircraft were developed for modeling of the anticipated helicopter traffic. In addition, it is assumed the proposed pavements will also be utilized by ground support vehicles (i.e. passenger vehicles, maintenance trucks, emergency vehicles, fueling equipment, tug equipment, etc). To model these vehicles, a combination of single and dual axle trucks, passenger vehicles, and emergency vehicles were included in the

FAARFIELD analysis. The client and design engineer should be aware that assumptions have been made regarding the anticipated traffic. Once the design and configuration for the proposed improvements proceed to a more finalized plan, the recommendations within this report should be reviewed and revised, if necessary. A copy of the FAA FAARFIELD 2.1

Structure Report is included in Appendix C.

5.5.3 The recommended concrete pavement sections are indicated in the following table. Geocon does not practice in the field of airport traffic engineering. The actual airport traffic should be determined by the project's civil engineer. If pavement sections for areas other than those listed below are required, Geocon should be contacted to provide additional recommendations.

PRELIMINARY CONCRETE PAVEMENT DESIGN SECTIONS

Location

P‐501 Concrete

Pavement

Thickness

(inches)

P‐209 Crushed

Aggregate Based

(inches)

Compacted

Subgrade

(inches)

Flight Line, Apron, Parking, etc.

6.5 6.0 12.0

Touchdown and Liftoff

Area (LTOF)

12.0 12.0 12.0

5.5.4 Concrete pavement should conform to Item P‐501 of AC 150/5370‐10H (FAA, 2018). Crushed

Aggregate base materials should conform to Item P‐209 of AC 150/5370‐10H (FAA, 2018).

Aggregate base shall be compacted to 95 percent of the maximum density, as determined by

ASTM D 1557. The 95 percent compaction requirement for aggregate base assumes the proposed pavements will not support aircraft and/or vehicles with gross weights greater than

60,000 pounds. A relative compaction of 100 percent will be required if the proposed pavements will support traffic with gross weights greater than 60,000 pounds.

Project No. W1755‐99‐07 ‐ 10 ‐ November 10, 2025

5.5.5 The proposed pavements shall include appropriate control joints, construction joints, thickened edges, dowels, tie bars, joint sealants, and fillers in accordance with FAA Advisory

Circular (AC) 150/5320‐6G, Section 3.16. All joint types and associated hardware shall be designed and detailed to ensure proper load transfer, minimize potential for cracking, and accommodate expected thermal and shrinkage movements. Joint spacing, dimensions, and materials shall be selected to provide long‐term durability and performance under heliport operational loads and environmental conditions.

5.5.6 The performance of pavements is highly dependent upon providing positive surface drainage away from the edge of pavements. Ponding of water on or adjacent to the pavement will likely result in saturation of the subgrade materials and subsequent cracking, subsidence, and pavement distress. If planters are planned adjacent to paving, it is recommended that the perimeter curb be extended at least 12 inches below the bottom of the aggregate base to minimize the introduction of water beneath the paving.

5.6 Temporary Excavations

5.6.1 Excavations of less than 5 feet in height are expected during grading operations.

The excavations are expected to expose artificial fill and alluvial deposits, which may be subject to caving where granular soils are exposed. Temporary vertical excavations up to

5 feet in height may be attempted where loose soils or caving sands are not present, and where excavations are not surcharged by adjacent traffic or structures.

5.6.2 Vertical excavations greater than 5 feet or where surcharged by existing structures will require sloping or shoring measures in order to provide a stable excavation. Where sufficient space is available, temporary unsurcharged embankments could be sloped back at a uniform

1:1 slope gradient or flatter up to a maximum of 10 feet in height. A uniform slope does not have a vertical portion.

5.6.3 Where temporary construction slopes are utilized, the top of the slope should be barricaded to prevent vehicle and storage loads at the top of the slope within a horizontal distance equal to the height of the slope. If the temporary construction slopes are to be maintained during the rainy season, berms are suggested along the tops of the slopes where necessary to prevent runoff water from entering the excavation and eroding the slope faces. The soils exposed in the cut slopes should be inspected during excavation by our personnel and the contractor’s competent person so that modifications of the slopes can be made if variations in the soil conditions occur. All excavations should be stabilized within 30 days of initial excavation.

Project No. W1755‐99‐07 ‐ 11 ‐ November 10, 2025

5.7 Stormwater Infiltration

5.7.1 During the site exploration on October 3, 2025, borings B5, B6, B9, and B10 were utilized to perform percolation testing. The borings were excavated to depths of 20, 10, 5, and 5 feet below ground surface, respectively. Slotted casing was placed in the boring, and the annular space between the casing and the excavation was filled with gravel. The boring was then filled with water to pre‐saturate the soils. The casing was refilled with water, and percolation test readings were performed after repeated flooding of the cased excavation.

5.7.2 The field‐measured percolation rate has been adjusted to infiltration rates in accordance with San Bernardino County’s Technical Guidance Document for Water Quality Management

Plans, which references the Riverside County Flood Control and Water Conservation District, LID BMP Manual, Appendix A for infiltration basins. Additional correction factors may be required and should be applied by the engineer in responsible charge of the design of the stormwater infiltration system and based on applicable guidelines. Percolation test results are provided as Figures .

Boring Soil Type

Infiltration

Depth

(ft)

Measured

Percolation Rate

(min/inch)

Corrected Infiltration

Rate (in/hour)

B5 Sand (SP) 15 ‐ 20 0.42 11.08

B6 Silty Sand (SM) 8 – 10 1.67 3.71

B9 Sand (SP) 2 – 5 0.56 6.63

B10 Sand (SP) 2 – 5 0.64 6.20

5.7.3 The results of the percolation testing indicate that the soils are conducive to infiltration. It is our opinion that the soil zones encountered at the depths and location of borings as listed in the table above are suitable for infiltration of stormwater.

5.7.4 It is our opinion that the introduction of stormwater at the depth and location indicated above will not induce excessive hydro‐consolidation, will not create a perched groundwater condition, will not affect soil structure interaction of existing or proposed foundations due to expansive soils, will not saturate soils supported by existing or proposed retaining walls, and will not increase the potential for liquefaction. Resulting settlements are anticipated to be less than ¼ inch, if any.

Project No. W1755‐99‐07 ‐ 12 ‐ November 10, 2025

5.7.5 The infiltration system must be located such that the closest distance between an adjacent foundation is at least 15 feet in all directions from the zone of saturation. The zone of saturation may be assumed to project downward from the discharge of the infiltration facility at a gradient of 1:1. The stormwater infiltration system must still be sufficiently deep to maintain the 15‐foot vertical offset between the bottom of footings and the zone of saturation. Additional property line or foundation setbacks may be required by the governing jurisdiction and should be incorporated into the stormwater infiltration system design as necessary.

5.7.6 Where the infiltration system penetrates below a foundation influence line, the proposed stormwater infiltration system must be designed to resist the surcharge from the adjacent foundation. The foundation surcharge line may be assumed to project down away from the bottom of the foundation at a 1:1 gradient.

5.7.7 Subsequent to the placement of the infiltration system, it is acceptable to backfill the resulting void space between the excavation sidewalls and the infiltration system with a minimum two‐sack slurry, provided the slurry is not placed in the infiltration zone. It is recommended that pea gravel be utilized adjacent to the infiltration zone so communication of water to the soil is not hindered.

5.7.8 Due to the preliminary nature of the project at this time, the type of stormwater infiltration system and the location of the stormwater infiltration systems have not yet been determined. The design drawings should be reviewed and approved by the Geotechnical

Engineer. The installation of the stormwater infiltration system should be observed and approved by the Geotechnical Engineer (a representative of Geocon).

5.8 Surface Drainage

5.8.1 Proper surface drainage is critical to the future performance of the project. Uncontrolled infiltration of irrigation excess and storm runoff into the soils can adversely affect the performance of the planned improvements. Saturation of a soil can cause it to lose internal shear strength and increase its compressibility, resulting in a change in the original designed engineering properties. Proper drainage should be maintained at all times.

Project No. W1755‐99‐07 ‐ 13 ‐ November 10, 2025

5.8.2 All site drainage should be collected and controlled in non‐erosive drainage devices. Drainage should not be allowed to pond anywhere on the site, and especially not against any foundation or retaining wall. The site should be graded and maintained such that surface drainage is directed away from structures in accordance with 2022 CBC 1804.4 or other applicable standards.

5.8.3 Positive site drainage should be provided away from structures, pavement, and the tops of slopes to swales or other controlled drainage structures.

5.8.4 Landscaping planters immediately adjacent to paved areas are not recommended due to the potential for surface or irrigation water to infiltrate the pavement's subgrade and base course. Either a subdrain, which collects excess irrigation water and transmits it to drainage structures, or impervious above‐grade planter boxes should be used. In addition, where landscaping is planned adjacent to the pavement, it is recommended that consideration be given to providing a cutoff wall along the edge of the pavement that extends at least

12 inches below the base material.

5.9 Plan Review

5.9.1 Grading plans should be reviewed by the Geotechnical Engineer (a representative of Geocon

West, Inc.), prior to finalization to verify that the plans have been prepared in substantial conformance with the recommendations of this report and to provide additional analyses or recommendations.

SHR Flight Line Pavement

Replacement Project

Project No. W1755‐99‐07 November 10, 2025

LIMITATIONS AND UNIFORMITY OF CONDITIONS

1. The firm that performed the geotechnical investigation for the project should be retained to provide testing and observation services during construction to provide continuity of geotechnical interpretation and to check that the recommendations presented for geotechnical aspects of site development are incorporated during site grading, construction of improvements, and excavation of foundations. If another geotechnical firm is selected to perform the testing and observation services during construction operations, that firm should prepare a letter indicating its intent to assume the responsibilities of the project geotechnical engineer of record. A copy of the letter should be provided to the regulatory agency for their records. In addition, that firm should provide revised recommendations concerning the geotechnical aspects of the proposed development, or a written acknowledgement of their concurrence with the recommendations presented in our report. They should also perform additional analyses deemed necessary to assume the role of Geotechnical Engineer of Record.

2. The recommendations of this report pertain only to the site investigated and are based upon the assumption that the soil conditions do not deviate from those disclosed in the investigation.

If any variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that anticipated herein, Geocon Incorporated should be notified so that supplemental recommendations can be given. The evaluation or identification of the potential presence of hazardous or corrosive materials was not part of the scope of services provided by Geocon Incorporated.

3. This report is issued with the understanding that it is the responsibility of the owner or his representative to ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and incorporated into the plans, and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field.

4. The findings of this report are valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years.

LIST OF REFERENCES

1. California Department of Water Resources, 2025, Water Data Library (WDL) Station Map, Website: https://wdl.water.ca.gov/waterdatalibrary/

2. Carson, S.E. and Matti, J.C., 1985 Contour Map Showing Minimum Deptb to Ground Water, Upper Santa Ana River Valley, California, 1973‐1979, USGS Miscellaneous Field Studies Map MF 1802.

3. California Geological Survey, 2010, Geologic Compilation of Quaternary Surficial Deposits in Southern California, San Bernardino 30’ X 60’ Quadrangle, A Project for the Department of Water Resources by the California Geological Survey, Compiled from existing sources by Trinda L. Bedrossian, CEG and Peter D. Roffers, CGS Special Report 217, Plate 13, Scale 1:100,000.

4. FAA, 2018, Advisory Circular 150/5370‐10H, Standard Specifications for Construction of Airports, dated December 21, 2018.

5. FAA, 2021, Advisory Circular 150/5320‐6G, Airport Pavement Design and Evaluation, dated June 7, 2021.

6. FAA, 2022, Advisory Circular 150/5335‐5D, Standardized Method of Reportting Airport Pavement Strength – PCR, dated April 29, 2022.

7. FAA, 2023, Advisory Circular 150/5390‐2D, Heliport Design, dated January 5, 2023.

8. San Bernardino, County of, 2020, Countywide Plan, County Policy Plan, adopted 2020, Website:

https://countywideplan.sbcounty.gov/resources/

REFERENCE: U.S.G.S. TOPOGRAPHIC MAPS, 7.5 MINUTE SERIES, REDLANDS, CA QUADRANGLE

LATITUDE: 34.1015

LONGTITUDE: -117.2277

FIG. 1

VICINITY MAP

PHONE (818) 841-8388 - FAX (818) 841-1704

500 NORTH VICTORY BOULEVARD BURBANK, CA 91502

ENVIRONMENTAL GEOTECHNICAL MATERIALS

CHECKED BY: GAKDRAFTED BY: NP PROJECT NO. W1755-99-07NOV 2025

SAN BERNARDINO INTERNATIONAL AIRPORT

SAN BERNARDINO, CALIFORNIA

SITE

Property Limits

Number and Location of Boring

B3

PHONE (818) 841-8388 - FAX (818) 841-1704

500 N. VICTORY BLVD. - BURBANK, CA 91502

NORTH

0 20'10'

LEGEND

B1B2

B7

B4

B6

B5

B8

B9

B10

ENVIRONMENTAL GEOTECHNICAL MATERIALS

CHECKED BY: GAKDRAFTED BY: NP PROJECT NO. W1755-99-07

SITE PLAN

NOV 2025 FIG. 2

SAN BERNARDINO, CALIFORNIA

SAN BERNARDINO INTERNATIONAL AIRPORT

B10

Date:

USCS Soil Classification:

Infiltration Rate Calculation:

minutes inches inches inches inches

199 Hangar Way

Sand Bernardino, California

San Bernardino International Airport

DRAFTED BY: LW CHECKED BY: MAC NOVEMBER 2025 PROJECT NO. W1755-06-07 FIG. 3

Total Depth of Test Hole, Dt = 240

Infiltration Rate, It = 11.08 inches/hour

PERCOLATION TEST RESULTS AND CALCULATIONS

ENVIRONMENTAL GEOTECHNICAL MATERIALS

500 NORTH VICTORY BOULEVARD - BURBANK, CA 91502

PHONE: 818-841-8388 FAX: 818-841-1704

Initial Depth to Water, D0 = 204.0 Havg = 24.0 inches

Test Hole Radius, r = 4 ΔH = 24.0 inches

Final Depth to Water, Df = 228.0 Hf = 12.0 inches

Time Interval, Δt = 10.00 Ho = 36.0 inches

24.0 0.42228.0

6 10:50 PM 11:00 PM 10.00 204.0

24.0 0.42

24.0 0.42

186.0

5 10:40 AM 10:50 AM 10.00 168.0

4 10:30 PM 10:40 PM 10.00 192.0

192.0

216.0

Df

Final Depth to Water

(in)

3 10:20 AM 10:30 AM 10.00 192.0

2 10:10 PM 10:20 PM 10.00 162.0

216.0 24.0 0.42

24.0 0.42

*If two consecutive measurements show that six inches of water seeps away in less than 25 minutes, the test shall be run for an additional hour with measurements, taken every 10 minutes. Otherwise, pre-soak (fill) overnight. Obtain at least twelve measurements per hole over at least six hours (approximately 30 minute intervals) with a precision of at least 0.25".

yes

1 10:00 AM 10:10 AM 10.00 144.0

Trial No. Start Time End Time

Δt

Time

Interval

(min)

D0

Initial

Depth to

Water

(in)

168.0 24.0 0.42

ΔD

Change in

Water Level

(in)

Percolation Rate

(min/in)

2 9:30 AM 9:55 AM 25 192.0 240

1 9:00 AM 9:25 AM 25 192.0 240 48

48 yes

Trial No. Start Time End Time

Δt

Time

Interval

(min)

D0

Initial Depth to

Water

(in)

Df

Final Depth to Water

(in)

ΔD

Change in

Water Level

(in)

Greater than or

Equal to

6"?

(y/n)

Diameter (if round) = 8 Sides (if rectangular) = -- --

PERCOLATION TEST DATA SHEET

Project: SHR Aviation Flight Line Project No.: W1755-06-07 Friday, October 3, 2025

Sandy Soil Criteria Test*

Test Hole Dimensions (inches) Length Width

Test Hole No.: B-5 Tested By: NP

Depth of Test Hole, DT: 20 SP

Infiltration Rate Calculation:

minutes inches inches inches inches

PERCOLATION TEST DATA SHEET

Project: SHR Aviation Flight Line Project No.: W1755-06-07 Friday, October 3, 2025

Sandy Soil Criteria Test*

Test Hole Dimensions (inches) Length Width

Test Hole No.: B-6 Tested By: NP

Depth of Test Hole, DT: 10 SM

Δt

Time

Interval

(min)

D0

Initial Depth to

Water

(in)

Df

Final Depth to Water

(in)

ΔD

Change in

Water Level

(in)

Greater than or

Equal to

6"?

(y/n)

Diameter (if round) = 8 Sides (if rectangular) = -- --

2 9:50 AM 10:15 AM 25 84.0 120

1 9:20 AM 9:45 AM 25 84.0 120 36

36 yes

Trial No. Start Time End Time

*If two consecutive measurements show that six inches of water seeps away in less than 25 minutes, the test shall be run for an additional hour with measurements, taken every 10 minutes. Otherwise, pre-soak (fill) overnight. Obtain at least twelve measurements per hole over at least six hours (approximately 30 minute intervals) with a precision of at least 0.25".

yes

1 10:20 AM 10:30 AM 10.00 96.0

Trial No. Start Time End Time

Δt

Time

Interval

(min)

D0

Initial

Depth to

Water

(in)

110.4 14.4 0.69

ΔD

Change in

Water Level

(in)

Percolation Rate

(min/in)

Df

Final Depth to Water

(in)

3 10:40 AM 10:50 AM 10.00 93.6

2 10:30 PM 10:40 PM 10.00 99.6

103.2 9.6 1.04

8.4 1.19108.0

5 11:00 AM 11:10 AM 10.00 88.8

4 10:50 PM 11:00 PM 10.00 103.2

99.6

108.0

10.8 0.93

4.8 2.08

6 11:10 PM 11:20 PM 10.00 99.6 6.0 1.67105.6

Time Interval, Δt = 10.00 Ho = 20.4 inches

Final Depth to Water, Df = 105.6 Hf = 14.4 inches

Test Hole Radius, r = 4 ΔH = 6.0 inches

Initial Depth to Water, D0 = 99.6 Havg = 17.4 inches

199 Hangar Way

Sand Bernardino, California

San Bernardino International Airport

DRAFTED BY: LW CHECKED BY: MAC NOVEMBER 2025 PROJECT NO. W1755-06-07 FIG. 4

Total Depth of Test Hole, Dt = 120

Infiltration Rate, It = 3.71 inches/hour

PERCOLATION TEST RESULTS AND CALCULATIONS

ENVIRONMENTAL GEOTECHNICAL MATERIALS

500 NORTH VICTORY BOULEVARD - BURBANK, CA 91502

PHONE: 818-841-8388 FAX: 818-841-1704

Infiltration Rate Calculation:

minutes inches inches inches inches

PERCOLATION TEST DATA SHEET

Project: SHR Aviation Flight Line Project No.: W1755-06-07 Friday, October 3, 2025

Sandy Soil Criteria Test*

Test Hole Dimensions (inches) Length Width

Test Hole No.: B-9 Tested By: NP

Depth of Test Hole, DT: 5 SP

Δt

Time

Interval

(min)

D0

Initial Depth to

Water

(in)

Df

Final Depth to Water

(in)

ΔD

Change in

Water Level

(in)

Greater than or

Equal to

6"?

(y/n)

Diameter (if round) = 8 Sides (if rectangular) = -- --

2 12:30 PM 12:55 PM 25 36.0 60

1 12:00 PM 12:25 PM 25 36.0 60 24

24 yes

Trial No. Start Time End Time

*If two consecutive measurements show that six inches of water seeps away in less than 25 minutes, the test shall be run for an additional hour with measurements, taken every 10 minutes. Otherwise, pre-soak (fill) overnight. Obtain at least twelve measurements per hole over at least six hours (approximately 30 minute intervals) with a precision of at least 0.25".

yes

1 1:00 PM 1:10 PM 10.00 31.2

Trial No. Start Time End Time

Δt

Time

Interval

(min)

D0

Initial

Depth to

Water

(in)

54.0 22.8 0.44

ΔD

Change in

Water Level

(in)

Percolation Rate

(min/in)

Df

Final Depth to Water

(in)

3 1:20 PM 1:30 PM 10.00 21.6

2 1:10 PM 1:20 PM 10.00 26.4

49.2 27.6 0.36

25.2 0.4051.6

5 1:40 PM 1:50 PM 10.00 32.4

4 1:30 PM 1:40 PM 10.00 20.4

45.6

48.0

13.2 0.76

27.6 0.36

6 1:50 PM 2:00 PM 10.00 20.4 18.0 0.5638.4

Time Interval, Δt = 10.00 Ho = 39.6 inches

Final Depth to Water, Df = 38.4 Hf = 21.6 inches

Test Hole Radius, r = 4 ΔH = 18.0 inches

Initial Depth to Water, D0 = 20.4 Havg = 30.6 inches

199 Hangar Way

Sand Bernardino, California

San Bernardino International Airport

DRAFTED BY: LW CHECKED BY: MAC NOVEMBER 2025 PROJECT NO. W1755-06-07 FIG. 5

Total Depth of Test Hole, Dt = 60

Infiltration Rate, It = 6.63 inches/hour

PERCOLATION TEST RESULTS AND CALCULATIONS

ENVIRONMENTAL GEOTECHNICAL MATERIALS

500 NORTH VICTORY BOULEVARD - BURBANK, CA 91502

PHONE: 818-841-8388 FAX: 818-841-1704

Infiltration Rate Calculation:

minutes inches inches inches inches

PERCOLATION TEST DATA SHEET

Project: SHR Aviation Flight Line Project No.: W1755-06-07 Friday, October 3, 2025

Sandy Soil Criteria Test*

Test Hole Dimensions (inches) Length Width

Test Hole No.: B-10 Tested By: NP

Depth of Test Hole, DT: 5 SP

Δt

Time

Interval

(min)

D0

Initial Depth to

Water

(in)

Df

Final Depth to Water

(in)

ΔD

Change in

Water Level

(in)

Greater than or

Equal to

6"?

(y/n)

Diameter (if round) = 8 Sides (if rectangular) = -- --

2 12:45 AM 1:10 AM 25 24.0 60

1 12:15 PM 12:40 PM 25 24.0 60 36

36 yes

Trial No. Start Time End Time

*If two consecutive measurements show that six inches of water seeps away in less than 25 minutes, the test shall be run for an additional hour with measurements, taken every 10 minutes. Otherwise, pre-soak (fill) overnight. Obtain at least twelve measurements per hole over at least six hours (approximately 30 minute intervals) with a precision of at least 0.25".

yes

1 1:15 AM 1:25 AM 10.00 24.0

Trial No. Start Time End Time

Δt

Time

Interval

(min)

D0

Initial

Depth to

Water

(in)

52.8 28.8 0.35

ΔD

Change in

Water Level

(in)

Percolation Rate

(min/in)

Df

Final Depth to Water

(in)

3 1:35 AM 1:45 AM 10.00 24.0

2 1:25 PM 1:35 PM 10.00 24.0

40.8 16.8 0.60

18.0 0.5642.0

5 1:55 AM 2:05 AM 10.00 24.0

4 1:45 PM 1:55 PM 10.00 24.0

40.2

44.4

16.2 0.62

20.4 0.49

6 2:05 PM 2:15 PM 10.00 24.0 15.6 0.6439.6

Time Interval, Δt = 10.00 Ho = 36.0 inches

Final Depth to Water, Df = 39.6 Hf = 20.4 inches

Test Hole Radius, r = 4 ΔH = 15.6 inches

Initial Depth to Water, D0 = 24.0 Havg = 28.2 inches

199 Hangar Way

Sand Bernardino, California

San Bernardino International Airport

DRAFTED BY: LW CHECKED BY: MAC NOVEMBER 2025 PROJECT NO. W1755-06-07 FIG. 6

Total Depth of Test Hole, Dt = 60

Infiltration Rate, It = 6.20 inches/hour

PERCOLATION TEST RESULTS AND CALCULATIONS

ENVIRONMENTAL GEOTECHNICAL MATERIALS

500 NORTH VICTORY BOULEVARD - BURBANK, CA 91502

PHONE: 818-841-8388 FAX: 818-841-1704

APPENDIX A

APPENDIX A

FIELD INVESTIGATION

The site was explored on October 3, 2025, by excavating ten 8‐inch‐diameter borings using a truck‐ mounted hollow‐stem auger drilling machine to a maximum depth of approximately 20½ feet beneath the ground surface. Representative and relatively undisturbed samples were obtained by driving a

3‐inch, O. D., California Modified Sampler into the “undisturbed” soil mass with blows from a

140‐pound auto‐hammer falling 30 inches. The California Modified Sampler was equipped with 1‐inch by 23/8‐inch diameter brass sampler rings to facilitate soil removal and testing. Bulk samples were also obtained.

The soil conditions encountered in the borings were visually examined, classified and logged in general accordance with the Unified Soil Classification System (USCS). The logs of the borings are presented on

Figures A1 through A10. The logs depict the soil and geologic conditions encountered and the depth at which samples were obtained. The logs also include our interpretation of the conditions between sampling intervals. Therefore, the logs contain both observed and interpreted data. We determined the lines designating the interface between soil materials on the logs using visual observations, penetration rates, excavation characteristics and other factors. The transition between materials may be abrupt or gradual. Where applicable, the logs were revised based on subsequent laboratory testing.

The approximate locations of the borings are shown on Figure 2.

Soil Boring Number: B-1

PROJECT NAME SHR Aviation Flight Line Replacement LOGGED BY LW

PROJECT NUMBER W1755-99-07 LATITUDE / LONGITUDE 34.1015, -117.2277

BORING DATE 10/03/2025 FIGURE NUMBER A1 DEPTH 10.5' SURFACE ELEVATION N/A

LOCATION 199 Hangar Way, San Bernardino, CA CLIENT NAME SB County Project and Facilities Management Department

DRILLING FIRM - COMPLETED 10/03/2025 EQUIPMENT Hollow Stem Auger -

METHOD Cal-Mod BORING DIAMETER 8 in HAMMER TYPE Auto NOTES -

HAMMER WEIGHT / DROP 140 lb / 30 in

De pt h (ft

W at er L ev el s

Gr ap hi c

Lo g

U

SC

S

Fill

SP

Material Description

ARTIFICIAL FILL (AC: 5" BASE: 4.5")

SAND, poorly graded, medium dense, slightly moist, brown, medium-grained, some fine-grained loose

ALLUVIUM

SAND, poorly graded, medium dense, slightly moist, grayish brown, medium-grained, trace gravel

Total depth of boring: 10.5 feet Fill to 6 feet.

No groundwater encountered.

Backfilled with soil cuttings and tamped.

Concrete patched.

Bu lk

Dr iv en

Sa m pl e

N um be r

BULK:

0-5'

B1@2.5'

B1@5'

B1@7.5'

B1@10' Bl ow C ou nt s/ 6”

Dr y De ns ity

(p cf

117.0

110.6

111.5

115.3

M oi st ur e Co nt en t (

3.2

5.0

3.6

2.3

NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. THE STRATIFICATION LINES PRESENTED HEREIN REPRESENT THE

APPROXIMATE BOUNDARY BETWEEN EARTH TYPES; THE TRANSITIONS MAY BE GRADUAL.

Soil Boring Number: B-2

PROJECT NAME SHR Aviation Flight Line Replacement LOGGED BY NP

PROJECT NUMBER W1755-99-07 LATITUDE / LONGITUDE 34.1022, -117.2278

BORING DATE 10/03/2025 FIGURE NUMBER A2 DEPTH 5.5' SURFACE ELEVATION N/A

LOCATION 199 Hangar Way, San Bernardino, CA CLIENT NAME SB County Project and Facilities Management Department

DRILLING FIRM - COMPLETED 10/03/2025 EQUIPMENT Hollow Stem Auger -

METHOD Cal-Mod BORING DIAMETER 8 in HAMMER TYPE Auto NOTES -

HAMMER WEIGHT / DROP 140 lb / 30 in

De pt h (ft

W at er L ev el s

Gr ap hi c

Lo g

U

SC

S

Fill

Material Description

ARTIFICIAL FILL (AC: 4" BASE: 5")

Silty SAND, medium dense, slightly moist, brown, fine-grained dense Total depth of boring: 5.5 feet

All fill.

No groundwater encountered.

Backfilled with soil cuttings and tamped.

Concrete patch.

Bu lk

Dr iv en

Sa m pl e

N um be r

BULK:

0-5'

B2@2.5'

B2@5'

Bl ow

C ou nt s/

6”

Dr y

De ns ity (p cf

126.2

118.1

M oi st ur e Co nt en t (

6.0

4.8

NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. THE STRATIFICATION LINES PRESENTED HEREIN REPRESENT THE

Soil Boring Number: B-3

PROJECT NAME SHR Aviation Flight Line Replacement LOGGED BY NP

PROJECT NUMBER W1755-99-07 LATITUDE / LONGITUDE 34.1021, -117.2283

BORING DATE 10/03/2025 FIGURE NUMBER A3 DEPTH 10.5' SURFACE ELEVATION N/A

LOCATION 199 Hangar Way, San Bernardino, CA CLIENT NAME SB County Project and Facilities Management Department

DRILLING FIRM - COMPLETED 10/03/2025 EQUIPMENT Hollow Stem Auger -

METHOD Cal-Mod BORING DIAMETER 8 in HAMMER TYPE Auto NOTES -

HAMMER WEIGHT / DROP 140 lb / 30 in

De pt h (ft

W at er L ev el s

Gr ap hi c

Lo g

U

SC

S

Fill

SP

Material Description

ARTIFICIAL FILL (AC: 5" BASE: 5")

SAND, poorly graded, medium dense, slightly moist, brown, fine-grained

ALLUVIUM

SAND, poorly graded, loose, slightly moist, brown, fine-grained grayish brown, medium-grained medium dense, reddish brown, cobble Total depth of boring: 10.5 feet

Fill to 4 feet.

No groundwater encountered.

Backfilled with soil cuttings and tamped.

Concrete patched.

Bu lk

Dr iv en

Sa m pl e

N um be r

BULK:

0-5'

B3@2.5'

B3@5'

B3@7.5'

B3@10' Bl ow C ou nt s/ 6”

Dr y De ns ity

(p cf

112.5

108.5

104.4

106.9

M oi st ur e Co nt en t (

5.1

6.7

3.7

4.6

NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. THE STRATIFICATION LINES PRESENTED HEREIN REPRESENT THE

Soil Boring Number: B-4

PROJECT NAME SHR Aviation Flight Line Replacement LOGGED BY NP

PROJECT NUMBER W1755-99-07 LATITUDE / LONGITUDE 34.1011, -117.2283

BORING DATE 10/03/2025 FIGURE NUMBER A4 DEPTH 5.5' SURFACE ELEVATION N/A

LOCATION 199 Hangar Way, San Bernardino, CA…