Ashland WWTP Headworks Upgrade - Geotechnical Engineering Report_STAMPED.pdf

Geotechnical Engineering Report

Version: Final

City of Ashland

Ashland Wastewater Treatment Plant Headworks Upgrade May 2026

Client Name: City of Ashland

Project Name: Ashland Wastewater Treatment Plant Headworks Upgrade

Project No: D4027000

Project Manager: Craig Massie, PE/Jacobs

Prepared by: Jithin Nair, PE/Jacobs

Version: Final

Date: May 29, 2026

Jacobs

1100 NE Circle Blvd Suite 300 Corvallis, OR 97330 United States

T +1.541.752.4271 www.jacobs.com

© Copyright 2026 Jacobs . All rights reserved. The content and information contained in this document are the property of the Jacobs group of companies (“Jacobs Group”). Publication, distribution, or reproduction of this document in whole or in part without the written permission of Jacobs Group constitutes an infringement of copyright. Jacobs, the Jacobs logo, and all other Jacobs Group trademarks are the property of Jacobs Group.

NOTICE: This document has been prepared exclusively for the use and benefit of Jacobs Group client. Jacobs Group accepts no liability or responsibility for any use or reliance upon this document by any third party.

Nair, Jithin Text Box Digitally signed by Jithin S Nair August 21, 2026

240215202253_b1fbb640 i

Contents Acronyms and Abbreviations ......................................................................................................................................... iii

1. Introduction ........................................................................................................................................................ 1-1

1.1 Scope of Work ......................................................................................................................................................... 1-1

1.2 Project Description ............................................................................................................................................... 1-1

2. Field Explorations .............................................................................................................................................. 2-1

3. Soil Laboratory Testing .................................................................................................................................... 3-1

4. Geology ................................................................................................................................................................ 4-1

5. Interpreted Site Conditions ............................................................................................................................. 5-1

5.1 Observed Subsurface Conditions .................................................................................................................... 5-1

5.2 Groundwater ........................................................................................................................................................... 5-1

6. Geotechnical Recommendations ................................................................................................................... 6-1

6.1 Seismic Design Parameters ............................................................................................................................... 6-1

6.2 Bearing Capacity and Subgrade Reaction ................................................................................................... 6-1

6.2.1 Bearing Capacity ....................................................................................................................................... 6-1

6.2.2 Coefficient of Subgrade Reaction ...................................................................................................... 6-2

6.3 Lateral Earth Pressure ......................................................................................................................................... 6-2

7. Limitations ........................................................................................................................................................... 7-1

8. References ........................................................................................................................................................... 8-1

Appendices Appendix A Test Pit Logs Appendix B Laboratory Test Results Appendix C Calculation Package

Tables Table 1. Summary of Geotechnical Explorations ................................................................................................................ 2-1

Table 2. Summary of Laboratory Index Test Results ........................................................................................................ 3-1

Table 3. Summary of Laboratory Corrosivity Test Results .............................................................................................. 3-1

Table 4. Summary of Risk-Targeted Seismic Design Parameters ............................................................................... 6-1

Table 5. Recommended Allowable Bearing Pressure ....................................................................................................... 6-2

Table 6. Coefficient of Subgrade Reaction ............................................................................................................................ 6-2

Table 7. Lateral Earth Pressure Coefficients, Ashland Wastewater Treatment Plant Grit Facility ................... 6-3

240215202253_b1fbb640 ii

Figures 1 Project Vicinity

2 Exploration Location Plan

3 Geology in the Project Area iii

Acronyms and Abbreviations AASHTO American Association of State Highway and Transportation Officials

ASTM ASTM International

City City of Ashland

GER geotechnical engineering report

MCE maximum considered earthquake

1-1

1. Introduction The City of Ashland (City) retained Jacobs to provide engineering consulting services for the design of the Ashland Wastewater Treatment Plant Headworks Upgrade. Authorization for the geotechnical scope of work is provided by the Professional Services Contract between the City and Jacobs effective August 25, 2025. As part of the project scope of work, Jacobs has prepared this geotechnical engineering report (GER) to present geotechnical data from the subsurface exploration program, Jacobs’ evaluation of the collected soil data and geotechnical analyses, and to provide geotechnical recommendations for the project.

1.1 Scope of Work

The City retained Jacobs to collect geotechnical data for the project. The scope of work performed by Jacobs consisted of the following:

Review geologic data along the project area and previously available geotechnical information.

Perform a subsurface exploration by excavating test pits in the vicinity of proposed major structures.

Perform laboratory testing on selected soil samples to evaluate engineering properties of subsurface materials along the pipeline.

Characterize subsurface conditions at the location of proposed structures based on geotechnical explorations and laboratory testing.

Provide seismic design recommendations for structures.

Provide shallow foundation recommendations for structures.

Provide lateral earth pressures recommendation for structures.

Prepare this GER.

1.2 Project Description

The City is planning upgrades to the existing wastewater treatment plant headworks. The upgrades include adding a new grit removal facility, demolishing existing mechanical and manual bar screens and replacing them with new mechanical bar screens and washer compactors, and installing pavement in the southwest corner of the plant. The objective of the project is to incorporate new facilities to increase the treatment capacity based on updated flow and load projections. The general project vicinity is shown on Figure 1.

2-1

2. Field Explorations Jacobs conducted geotechnical explorations at the site of the proposed new treatment facility in October 2025 to collect soil samples for laboratory testing and to observe soil materials and conditions. Jacobs previously performed geotechnical explorations just north of the wastewater treatment plan as part of the Ashland Wastewater Treatment Plant Outfall Reallocation in 2018. Based on Jacobs extensive experience and City’s observations from previous construction, the rock formation was expected to be shallow. As the foundations for the grit facility are expected to bear on bedrock layer, test pits to ascertain rock location were suitable for the project requirements. Three test pits were advanced in the vicinity of new grit removal facility. Figure 2 shows the approximate locations of the explorations at the project site.

Jacobs worked with the City to mark existing utilities and obtained necessary utility clearances before starting the geotechnical subsurface exploration program. Test pits were field located by Jacobs and adjusted to avoid utility conflicts. Table 1 lists the location coordinates, approximate elevation, and completion depth of each test pit.

Table 1. Summary of Geotechnical Explorations

Boring No. Latitude Longitude Ground Surface Elevation

(feet) Completion Depth

(feet bgs)

TP-1-25 42.21305 -122.71450 1,747 9.4

TP-2-25 42.21288 -122.71496 1,752 6.2

TP-3-25 42.21271 -122.71487 1,754 8.4

Abbreviations:

bgs = below ground surface

The exploratory test pits were advanced using a Deere 410L excavator with a 2-foot-wide bucket with teeth, capable of digging to a depth of approximately 15 feet. The test pits were located within the foundation footprint and in the vicinity of upgrades. Locations were measured from existing site features during the field investigation. Therefore, the locations and elevations are approximate.

Test pits were logged visually from the ground surface and from samples collected from the excavator.

The maximum depth explored was approximately 9.4 feet. For this exploration program, test pit depths were governed by refusal due to rock. No groundwater observed during exploration.

The Jacobs field representative provided continuous field observations and logging of the soils encountered. Visual classification of collected soil samples was completed in accordance with ASTM International (ASTM) D2488, Standard Practice for Description and Identification of Soils (Visual-Manual Procedures). Sample descriptions and observations made during excavations were recorded on the test pit logs, which can be found in Appendix A.

Where laboratory tests were available, the soil classification was reevaluated and updated in accordance with ASTM D2487, Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System).

3-1

3. Soil Laboratory Testing FEI Testing & Inspection, Inc. of Tangent, Oregon, performed a series of laboratory tests requested by Jacobs on selected representative soil samples recovered from the test pits. The visual field classifications were modified, as necessary, based on laboratory test results. The laboratory tests were conducted in accordance with applicable ASTM and American Association of State Highway and Transportation Officials (AASHTO) standards:

Particle-size analysis in accordance with ASTM D6913, Standard Test Methods for Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis

Soil Resistivity in accordance with AASHTO T 288-91, Standard Method of Test for Determining Minimum Laboratory Soil Resistivity

Sulfate content in accordance with AASHTO T 290-95, Standard Method of Test for Determining Water-Soluble Sulfate Ion Content in Soil

Chloride content in accordance with AASHTO T 291-94, Standard Method of Test for Determining Water-Soluble Chloride Ion Content in Soil pH with AASHTO T 289-91, Standard Method of Test for Determining pH of Soil for Use in Corrosion Testing

Tables 2 and 3 summarize the laboratory test results, which also are presented on the test pit logs in Appendix A next to the corresponding sample. Appendix B provides the laboratory testing results.

Table 2. Summary of Laboratory Index Test Results

Boring No. Sample No.

Depth

(feet bgs) USCS Soil

Type

Moisture Content

Sieve

Gravel

Sand

Fines

TP-1-25 1-GS 5 GM NA 45 34 21

Abbreviations:

bgs = below ground surface NA = not applicable GM = silty gravel USCS = Unified Soil Classification System

Table 3. Summary of Laboratory Corrosivity Test Results

Boring No. Sample No.

Depth

(feet bgs) USCS Soil

Type

Corrosivity

Resistivity (ohm-cm)

Sulfate (mg/kg)

Chloride (mg/kg) pH

TP-1-25 1-GS 5 GM 3700 7.76 ND 7.65

Abbreviations:

bgs = below ground surface ND = not detected GM = silty gravel ohm-cm = ohm-centimeter Mg/kg = milligrams per kilogram USCS = Unified Soil Classification System

4-1

4. Geology The project area is located in the southern portion of the Bear Creek Valley between the Siskiyou Mountains of the larger Klamath Mountains province in the west and the Cascade Range province to the east. The valley is a deep sediment-filled valley consisting of mostly sandstones dating back to the Cretaceous period, gradually being exposed through tectonic uplift and erosion. The uplift caused the deep sediments to be exposed to erosion due to weathering, stream action, landslides, and glaciation, creating steep mountains, exposing the underlying granite that is characteristic of the Ashland watershed (Siskiyou Research Group 2001). The predominant hydrologic feature is Bear Creek, which flows generally northwest to the Rogue River.

Local bedrock in the area is identified as marine sandstone, siltstone, and conglomerate of the Hornbrook Formation from the upper Cretaceous period (Wells 1956). The sandstone is greenish to buff arkosic sandstones with local layers of conglomerates consisting of gravels from quarts, diorite, gneiss, and greenstone. Quaternary alluvial deposits overlie the bedrock and consist of stratified gravel, sand, and silt.

Much of this alluvial material has been derived through erosion upstream, as well as colluvium that has entered the waterway. Figure 3 presents the geology of the project site.

5-1

5. Interpreted Site Conditions The new grit removal facility will most likely be built on the sandstone layer encountered at the site.

Results of field explorations, as well as information about geology described in Section 4, were used to evaluate surface and subsurface soil and groundwater conditions at the locations of the proposed improvements. Section 5.1 and 5.2 summarize the interpretation of available site condition information.

5.1 Observed Subsurface Conditions

The subsurface conditions observed during the field explorations can be divided into two general soil types, listed below from ground surface downward:

Fill: Fill material encountered at the site consisted of silty gravel with sand. Fill thickness varied from 6 to 9 feet thick. Fill was observed to be brown in color and medium dense.

Sandstone: The sandstone was encountered in all three test pits. The depth to sandstone varied, but was generally shallow at the project location and sloping down toward the canyon. The sandstone layer was observed to be tan in color with red to pink hue. The sandstone appears to be geologically young and fresh, exhibiting very little weathering. The upper 2- to 4-inch portions of sandstone appeared to have a hardness rating of medium hard. Samples of the rock could be broken with multiple blows. The rock became harder with depth and was unable to be excavated with the backhoe.

Detailed descriptions of the materials encountered in the soil explorations are presented in the soil boring logs in Appendix A.

5.2 Groundwater

No standing groundwater or seepage was observed in the test pits. As the project site location is near the top of the hill, no groundwater is expected. Perched water may be observed due to recent precipitation.

6-1

6. Geotechnical Recommendations

6.1 Seismic Design Parameters

Seismic design ground motion parameters were determined for the project site according to Minimum Design Loads for Buildings and Other Structures (ASCE 2022). This approach involves determining the spectral acceleration at a short period (SS) and at a 1-second period (S1) for a seismic event with a 2 percent probability of exceedance in 50 years (2,475-year return period).

Minimum Design Loads for Buildings and Other Structures (ASCE 2022) further identifies a methodology for defining the design spectra using the maximum considered earthquake (MCE) spectral values. This methodology involves adjustments for site class based on the stiffness of the soil and rock in the upper 100 feet of the site profile. The design ground motion is then obtained by multiplying the soil-adjusted MCE values by two-thirds. Following these methods and using the project site location and subsurface conditions identified previously, analyses were conducted to determine the design ground motions based on the code-based probabilistic MCE.

The test pits explored at the site confirm the presence of shallow bedrock. The presence of shallow bedrock indicates a site class B classification for the site, but the project site was classified as Site Class D for design conservatively. Site ground motions associated with Site Class D were obtained from the United States Geological Survey Seismic Design Maps web tool for the project alignment, based on coordinates of 42.213032° N latitude, 122.715002° W longitude. Results from this evaluation determined that the SS and S1 values for the MCE at the stiff soil interface are 0.68 g and 0.31 g, respectively, at the project site. The seismic design parameters are summarized in Table 4, and seismic evaluation calculations can be found in Appendix C.

Table 4. Summary of Risk-Targeted Seismic Design Parameters

Parameter Value1

Mapped short-period (at 0.2 seconds) spectral acceleration (Ss) 0.68 g

Mapped long-period (at 1-second) spectral acceleration (S1) 0.31 g

Site-adjusted MCE spectral acceleration at short periods (SMS) 0.95 g

Site-adjusted MCE spectral acceleration at 1.0-second period (SM1) 0.71 g

Peak Ground Acceleration (PGAM) 0.4

Design short-periods spectral acceleration (SDS) 0.63 g

Design long-period (at 1 second) spectral acceleration (SD1) 0.47 g

Notes:

1. Based on Minimum Design Loads for Buildings and Other Structures (ASCE 2022).

Abbreviations:

g = acceleration of gravity MCE = maximum considered earthquake MCEG = maximum considered earthquake geometric mean

6.2 Bearing Capacity and Subgrade Reaction

6.2.1 Bearing Capacity

Bearing capacity analysis was calculated using the Terzaghi et.al. (1996) bearing capacity equation based on the foundation dimensions, foundation soil shear strength, and soil unit weight. It is assumed the

6-2 footings will be constructed on an 8-inch layer of compacted granular fill, overlying native sandstone with an internal friction angle of 38 degrees for the grit facility. The sandstone below the compacted granular fill is assumed to partially fractured from the rock excavation process.

The coefficient of friction below the footing was estimated by using an interface friction angle of 25 degrees (2/3 of soil internal friction angle). The estimated coefficient of friction for sliding resistance is

0.47. Recommended allowable bearing pressure is shown in Table 5.

Table 5. Recommended Allowable Bearing Pressure

Structure Allowable Bearing Pressure

(psf)

Grit Facility 3,000

Abbreviations:

psf = pounds per square foot

6.2.2 Coefficient of Subgrade Reaction

Often, the design of shallow mat foundations involves the concentration of various magnitudes of point loads across the foundation. Typical analyses require a coefficient of subgrade reaction, which is defined as the ratio between the pressure at any given point on the surface of contact and the deformation produced by the load application at that point.

The coefficient subgrade reaction is usually estimated by conducting plate load test or by correlations with other soil properties. Based on the Terzaghi et al (1996) recommendations for stiff clays, the values shown in Table 6 have been estimated. This value represents the reaction of a 1-foot-square plate, referred to as KV1. To model larger foundations, grade beams, or pipes, additional revision is needed. For a foundation of width b (feet), and with a length-to-width ration of m, the actual value of the coefficient of subgrade reaction, Kb, can be estimated as follows:

𝐾b =

𝐾V1

𝑏 ൬ 𝑚 + 0.5

1.5𝑚 ൰

Adjusted values of the coefficient of subgrade reaction are shown in Table 6.

Table 6. Coefficient of Subgrade Reaction

Structure

Coefficient of Subgrade Reaction of 1-foot square plate, Kv1

(kcf)

Coefficient of Subgrade Reaction of the slab, Kb

(kcf)

Grit Facility 550 30

Abbreviations:

kcf = kips per cubic foot

6.3 Lateral Earth Pressure

In areas where native granular soil is not suitable to be used as a backfill (i.e., within the influence of foundation pressures), Jacobs recommends backfilling with an imported fill (total unit weight of 130 pounds per cubic foot and friction angle of 34 degrees). The imported fill should be placed in 6-inch loose lifts and compacted to a relative density of 95 percent maximum dry density. Considering groundwater will not be encountered at the site for the proposed construction, only drained static earth pressure values are provided.

6-3

For seismic loading conditions, additional seismic earth pressure should be added to the static active earth pressure. Note that the active and passive earth pressure has a triangular distribution, with the largest load occurring at the bottom of the wall, while the seismic earth pressure has an inverted triangular distribution, with the largest load at the top of the wall.

The larger of the at-rest pressure or dynamic active pressure should be used for design. Using the Mononobe-Okabe method (Seed and Whitman 1970, Mononobe and Matsuo 1929, and Okabe 1926), the lateral earth pressure loads from static and seismic loading are calculated as follows:

EAE = ½∙∙H2∙Kae (resultant static plus seismic active force)

Where:

EAE = lateral active earth pressure force, including static and seismic conditions total unit weight of the soil H = wall height Kae = seismic active earth pressure coefficient

Active and passive seismic pressure was estimated using the Mononobe-Okabe method.

The location of the resultant earth pressure force (YEAE) is dependent on the relative magnitude of the static and dynamic pressures, and is generally approximately 0.5 × H (wall height). The static pressure resultant (EA) acts at H/3 from the base of the wall, whereas the dynamic increment pressure resultant (EAE) acts at 0.6 x H from the base of the wall.

A summary of lateral earth pressure coefficient and equivalent fluid earth pressures is provided in Table 7, and lateral earth pressure coefficient calculations can be found in Appendix C.

Table 7. Lateral Earth Pressure Coefficients, Ashland Wastewater Treatment Plant Grit Facility

Design Parameter Imported Granular Fill

Soil Unit Weight, γ (pcf) 130

Soil Friction Angle, φ’ (degrees) 34

At-Rest Earth Pressure Coefficient (Ko) 0.44

Static Active Earth Pressure Coefficient (Ka) 0.25

Static Passive Earth Pressure Coefficient (Kp) 4.98

Seismic At-Rest Earth Pressure Coefficient (KOE) 0.64

Seismic Active Earth Pressure Coefficient (KAE) 0.4

Seismic Passive Earth Pressure Coefficient (KPE) 3.86

General Notes:

1. Assumed flat backslope behind the vertical wall.

2. Assumed drained conditions behind and in front of the walls.

3. An interface friction angle of two-thirds of the soil internal friction angle was used to calculate the earth pressure parameters.

4. The passive earth pressure parameters include a factor of safety of 1.5 any resistance factors.

Abbreviations:

pcf = pounds per cubic foot

7-1

7. Limitations This GER has been prepared for the exclusive use of the City of Ashland and Jacobs for specific application to the Ashland Wastewater Treatment Plant Headworks Upgrade Project in accordance with generally accepted geotechnical engineering practice. No other warranty, express or implied, is made.

The geotechnical recommendations provided in Section 6 of this GER are prepared specifically for the design of Ashland Wastewater Treatment Plant Headworks Upgrades by Jacobs and are not to be used for the bidding phase. Jacobs is not responsible for claims, damages, or liability associated with use of recommendations provided in Section 6.

The data, analysis and recommendations contained in this GER were collected during the geotechnical subsurface investigation program conducted in October 2025. Exploration data indicate subsurface conditions only at specific locations and times, and only to the depths penetrated. They do not necessarily reflect strata variations that may exist between such locations. Subsurface conditions and water levels at other locations may differ from conditions occurring at these locations. The nature and extent of variation may not become evident until materials are exposed during construction. The passage of time may result in a change in the conditions at these locations.

The methods used to estimate levels of earthquake ground shaking given in this report are based on work conducted by USGS, as well as by other scientists and engineers involved in earthquake studies. The nature of this work is such that uncertainties exist in the predictive methods and results. Whereas an effort has been made during this project to account for these uncertainties in the estimation of ground motions with currently available methods, higher levels of ground shaking could occur. The profession’s understanding of earthquake ground motions continues to evolve and, as a result, the basis of the recommendations given in this report could change in the future. These changes could necessitate reconsideration of the recommendations provided in this report.

If there are changes in the nature, design, or location of the planned facilities, the data contained in this GER should not be considered valid unless the changes are reviewed, and the data verified or modified in writing by Jacobs. Jacobs is not responsible for claims, damages, or liability associated with the subsurface data or reuse of the subsurface data without the express written authorization of Jacobs.

8-1

8. References American Society of Civil Engineers (ASCE). 2022. Minimum Design Loads and Associated Criteria for

Buildings and Other Structures. ASCE/SEI 7-22. Reston, VA.

Mononobe, N. and H. Matsuo. 1929. “On the Determination of Earth Pressure During Earthquakes.”

Proceedings: World Engineering Conference, Tokyo, 1929.

Okabe, S. 1926. “General Theory of Earth Pressure.” Journal of Japan Society of Civil Engineers 12(1).

Seed, H.B. and R.V. Whitman. 1970. “Design of Earth Retaining Structures for Dynamic Loads.” Lateral Stresses in the Ground and Design of Earth Retaining Structures: State-of-the-art Papers Presented at 1970 Specialty Conference. Pages 103-147. American Society of Civil Engineers. New York.

Siskiyou Research Group. 2001. Ashland Creek 2000 Level II Stream Survey Report, Rogue River National Forest, Ashland Ranger District, Ashland, Oregon. January.

Terzaghi, Karl, Ralph B. Peck, and Gholamreza Mesri. 1996. Soil Mechanics in Engineering Practice. Third Edition. John Wiley & Sons, Inc. New York, New York.

Wells, F.G. 1956. Geologic Map of the Medford Quadrangle, Oregon- California. U.S. Geological Survey Geologic Quadrangle 89. Report: 2 p.; Plate. https://doi.org/10.3133/gq89.

Figures

Ashland WWTP Headworks Upgrade Project Ashland, Oregon

Vicinity Map

Figure 1

GENERAL NOTES:

1. Map from Cal Topo (2026)

Project Site

SCALE : NTS

Exploration Location Plan

Figure 2

Geologic Map

Figure 3

GENERAL NOTES:

1. Map from 1956 Geologic Map of the Medford Quadrangle, Oregon-California, by F.G. wells. USGS GQ-89

Appendix A Test Pit Logs

1-GS

5.5

5.0 Collected sample 1-GS from 5 to 5.5 ft

LAB TESTING:

GRAVEL% : 45

SAND% : 34

FINES% : 21

Encountered sandstone approx. 9 feet, difficult to penetrate with excavator

END OF TEST PIT

Test pit terminated at 9.4 ft bgs.

Test pit backfilled with spoils, compacted with bucket in lifts

GRAVEL SURFACING

SILTY GRAVEL WITH SAND (GM)

brown, damp to moist, medium dense, subangular to subrounded gravel

SANDSTONE

redddish brown, fresh to slightly weathered (W1-W2), weak to medium strong rock (R2-R3), fine grained

Bottom of Boring at 9.4 ft bgs on

DATE EXCAVATED: 10/15/2025

TEST PIT NUMBER:

D402700 TP-1-25 SHEET 1 OF 1

TEST PIT LOG

CONTRACTOR: City of Ashland

EXCAVATION EQUIPMENT: Deere 410L Excavator, 2-ft wide bucket teeth

ELEVATION: 1747.0 ft

PROJECT: Ashland WWTP Headworks Design, Ashland, OR LOCATION: Grit Facility (42.2 N, -122.7 E)

PROJECT NUMBER:

D

E P

T H

B E

LO

W

S U

R F

A C

E

F T

IN

T

E R

V A

L (f t)

#T Y

P E

COMMENT

DIFFICULTY IN EXCAVATION,

RUNNING GRAVEL CONDITION,

COLLAPSE OF WALLS, SAND HEAVE,

DEBRIS ENCOUNTERED, WATER

SEEPAGE GRADATIONAL CONTACTS,

TEST, INSTRUMENTATION

SOIL NAME, USCS GROUP SYMBOL, COLOR,

MOISTURE CONTENT, RELATIVE DENSITY OR

CONSISTENCY, SOIL STRUCTURE, MINERALOGY

SOIL DESCRIPTIONSAMPLE

G R

A P

H

IC

L O

G

WATER LEVELS: Not Encountered LOGGER: JSNAPPROX. DIMENSIONS:

Nair, Jithin Typewriter 2 ft x 8 ft

4.5

4.0 Collected sample 1-GS from 4 to 4.5 ft

Encountered sandstone approx. 5.9 feet, difficult to penetrate with excavator

END OF TEST PIT

Test pit terminated at 6.2 ft bgs.

Test pit backfilled with spoils, compacted with bucket in lifts

TOPSOIL/DUFF

SILTY GRAVEL WITH SAND (GM)

brown, damp to moist, medium dense, subangular to subrounded gravel

SANDSTONE

redddish brown, fresh to slightly weathered (W1-W2), weak to medium strong rock (R2-R3), fine grained

Bottom of Boring at 6.2 ft bgs on

DATE EXCAVATED: 10/15/2025

TEST PIT NUMBER:

D402700 TP-2-25 SHEET 1 OF 1

TEST PIT LOG

CONTRACTOR: City of Ashland

EXCAVATION EQUIPMENT: Deere 410L Excavator, 2-ft wide bucket teeth

ELEVATION: 1752.0 ft

PROJECT: Ashland WWTP Headworks Design, Ashland, OR LOCATION: Grit Facility (42.2 N, -122.7 E)

PROJECT NUMBER:

D

E P

T H

B E

LO

W

S U

R F

A C

E

F T

IN

T

E R

V A

L (f t)

#T Y

P E

COMMENT

DIFFICULTY IN EXCAVATION,

RUNNING GRAVEL CONDITION,

COLLAPSE OF WALLS, SAND HEAVE,

DEBRIS ENCOUNTERED, WATER

SEEPAGE GRADATIONAL CONTACTS,

TEST, INSTRUMENTATION

SOIL NAME, USCS GROUP SYMBOL, COLOR,

MOISTURE CONTENT, RELATIVE DENSITY OR

CONSISTENCY, SOIL STRUCTURE, MINERALOGY

SOIL DESCRIPTIONSAMPLE

G R

A P

H

IC

L O

G

WATER LEVELS: Not Encountered LOGGER: JSNAPPROX. DIMENSIONS:

Nair, Jithin

5.5

5.0 Collected sample 1-GS from 5 to 5.5 ft

Encountered sandstone approx. 8 feet, difficult to penetrate with excavator

END OF TEST PIT

Test pit terminated at 8.4 ft bgs.

Test pit backfilled with spoils, compacted with bucket in lifts

TOPSOIL/DUFF

SILTY GRAVEL WITH SAND (GM)

brown, damp to moist, medium dense, subangular to subrounded gravel

SANDSTONE

redddish brown, fresh to slightly weathered (W1-W2), weak to medium strong rock (R2-R3), fine grained

Bottom of Boring at 8.4 ft bgs on

DATE EXCAVATED: 10/15/2025

TEST PIT NUMBER:

D402700 TP-3-25 SHEET 1 OF 1

TEST PIT LOG

CONTRACTOR: City of Ashland

EXCAVATION EQUIPMENT: Deere 410L Excavator, 2-ft wide bucket teeth

ELEVATION: 1754.0 ft

PROJECT: Ashland WWTP Headworks Design, Ashland, OR LOCATION: Grit Facility (42.2 N, -122.7 E)

PROJECT NUMBER:

D

E P

T H

B E

LO

W

S U

R F

A C

E

F T

IN

T

E R

V A

L (f t)

#T Y

P E

COMMENT

DIFFICULTY IN EXCAVATION,

RUNNING GRAVEL CONDITION,

COLLAPSE OF WALLS, SAND HEAVE,

DEBRIS ENCOUNTERED, WATER

SEEPAGE GRADATIONAL CONTACTS,

TEST, INSTRUMENTATION

SOIL NAME, USCS GROUP SYMBOL, COLOR,

MOISTURE CONTENT, RELATIVE DENSITY OR

CONSISTENCY, SOIL STRUCTURE, MINERALOGY

SOIL DESCRIPTIONSAMPLE

G R

A P

H

IC

L O

G

WATER LEVELS: Not Encountered LOGGER: JSNAPPROX. DIMENSIONS:

Nair, Jithin

Appendix B Laboratory Test Results

LETTER OF

TRANSMITTAL

Date: November 13, 2025 Project No.: 2255002-613

Re: Ashland WWTP Headworks Design

To: Jacobs

1100 NE Circle Blvd. Suite 300 Corvallis, OR 97330

Attn: Jithin Nair, M.Eng., E.I.T.

Jacobs Project No. D4022700

Enclosed are:

Report Drawings Test Results (2 Pages Total Incl. Cover)

Copy of Letter Specifications

Other

These are transmitted as checked below:

For your use For your review/approval As requested For your files

Remarks: Requested laboratory testing results attached. Please call if you have any questions.

Date Sampled: unknown Location Tested: Tangent Laboratory Sample No.: 1127

Copy to:

Signature:

Rachel Ray

President

This report and/or enclosed test data is the confidential property of the client to whom it is addressed and pertains to the specific process and/or material evaluated. As such, information contained herein shall not be reproduced in part or full and/or any part thereof be disclosed without FEI Testing & Inspection, Inc.'s written authorization.

31970 Cinema Way A · Tangent, Oregon 97389 · phone (541) 757-4698 29540 B Airport Road · Eugene, Oregon 97402 · phone (541) 684-3849 2256 Judson Street SE · Salem, Oregon 97302 · phone (971) 273-0672

Particle Size Distribution Report

ASTM C117 & C136

P E

R C

E N

T F

IN

E

R

GRAIN SIZE - mm.

0.0010.010.1110100

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0 16 29 6 11 17 21 in in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM C117 & C136) Material Description

Atterberg Limits

Coefficients

Classification

Test Remarks

Sample Date:

Source of Sample: 1127 Depth: 5.0' Sample Number: TP-1, S-1

Client:

Project:

Project No: Figure

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

Pct.

of

Fines

1" 3/4" 1/2" 3/8" 1/4" #4

#10 #20 #40 #60

#100 #200

21.3068 19.3774 7.2044

2.4135 0.2059

Jacobs

Ashland WWTP Headworks Design

2255002-613

PL= LL= PI=

D90= D85= D60= D50= D30= D15= D10= Cu= Cc=

USCS= AASHTO=

* (no specification provided)

FEI Testing & Inspection, Inc.

Tangent, OR

LETTER OF

TRANSMITTAL

Date: November 24, 2025 Project No.: 2255002-613

Re: Ashland WWTP Headworks Design

To: Jacobs

1100 NE Circle Blvd. Suite 300 Corvallis, OR 97330

Attn: Jithin Nair, M.Eng., E.I.T.

Jacobs Project No. D4022700

Enclosed are:

Report Drawings Test Results (16 Pages Total Incl. Cover)

Copy of Letter Specifications

Other

These are transmitted as checked below:

For your use For your review/approval As requested For your files

Remarks: Requested laboratory testing results attached. Please call if you have any questions.

Date Sampled: unknown Location Tested: Specialty Analytical Sample No.: 1127-A

Copy to:

Signature:

Rachel Ray

President

This report and/or enclosed test data is the confidential property of the client to whom it is addressed and pertains to the specific process and/or material evaluated. As such, information contained herein shall not be reproduced in part or full and/or any part thereof be disclosed without FEI Testing & Inspection, Inc.'s written authorization.

31970 Cinema Way A · Tangent, Oregon 97389 · phone (541) 757-4698 29540 B Airport Road · Eugene, Oregon 97402 · phone (541) 684-3849 2256 Judson Street SE · Salem, Oregon 97302 · phone (971) 273-0672

November 24, 2025

FEI Testing and Inspection, LLC.

Rachel Ray

Dear Rachel Ray:

RE: Ashland WWTP Headworks Design/ 22550 Order No.: 2511167

FAX:

TEL: (541) 757-4698

750 NW Cornell Ave

Corvallis, OR 97330

Specialty Analytical 9011 SE Jannsen Rd

Clackamas, OR 97015

TEL: (503) 607-1331

Website: www.specialtyanalytical.com

Marty French

There were no problems with the analysis and all data for associated QC met EPA or laboratory specifications, except where noted in the Case Narrative, or as qualified with flags. Results apply only to the samples analyzed. Without approval of the laboratory, the reproduction of this report is only permitted in its entirety.

If you have any questions regarding these tests, please feel free to call.

Sincerely, Lab Director

Current certificates and lists of licensed parameters can be found at specialtyanalytical.com

Specialty Analytical Certifications Accrediting Authority

Oregon Laboratory Accreditation Program

Washington Department of Ecology

Laboratory Number

C804

Project: Ashland WWTP Headworks Design/ 2255002-613

Client Sample ID TP-1, S-1 @ 5'

Collection Date:

Matrix: SOIL

CLIENT: FEI Testing and Inspection, LLC.

Lab ID: 2511167-001

11/24/2025

2511167

Date Reported:

WO#:

Analyses Result Qual Units Date AnalyzeDFRL

Specialty Analytical

CAS

SOIL RESISTIVITY T288-91 Analyst: AM

Minimum Soil Resistivity 11/19/2025 16:251.00 ohm-cm 13700

WATER SOLUBLE SULFATE ION T290-95 Analyst: AMSW9056PR

Sulfate 11/18/2025 14:540.733 mg/Kg 17.7614808-79-8

WATER SOLUBLE CHLORIDE T291-94 Analyst: AMSW9056PR

Chloride 11/18/2025 14:540.587 mg/Kg 1ND16887-00-6

PH OF SOIL-CORROSION TESTING T289-91 Analyst: AM pH 11/19/2025 15:500 pH Units 17.65

Project: Ashland WWTP Headworks Design/ 2255002-6

Client: FEI Testing and Inspection, LLC.

TestCode: CL_AASHTO

11/24/2025

QC SUMMARY REPORT

2511167WO#:

Specialty Analytical

Sample ID: CCV

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61413

SeqNo: 804274

CCVSampType: TestCode: CL_AASHTO

SW9056PR

Chloride 20.00 98.8 90 1101.00 019.8

Sample ID: CCV

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61413

SeqNo: 804276

CCVSampType: TestCode: CL_AASHTO

SW9056PR

Chloride 20.00 99.1 90 1101.00 019.8

Sample ID: 2511169-001ADUP

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/18/2025

Prep Date: 11/18/2025

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: BatchQC

RunNo: 61413

SeqNo: 804279

DUPSampType: TestCode: CL_AASHTO

SW9056PR

Chloride 20 RMI0.577 2.788 44.94.40

Sample ID: CCV

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/19/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61413

SeqNo: 804281

CCVSampType: TestCode: CL_AASHTO

SW9056PR

Chloride 20.00 96.2 90 1101.00 019.2

Qualifiers: H Holding times for preparation or analysis exceeded R RPD outside accepted recovery limits S Spike Recovery outside accepted recovery limits

TestCode: CL_AASHTO

11/24/2025

QC SUMMARY REPORT

2511167WO#:

Specialty Analytical

Sample ID: CCV

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/19/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61413

SeqNo: 804281

CCVSampType: TestCode: CL_AASHTO

SW9056PR

Sample ID: LCS

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/19/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: LCSS

RunNo: 61413

SeqNo: 804282

LCSSampType: TestCode: CL_AASHTO

SW9056PR

Chloride 10.00 95.9 85 1151.00 09.59

Sample ID: CCV

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/19/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61413

SeqNo: 804283

CCVSampType: TestCode: CL_AASHTO

SW9056PR

Chloride 20.00 99.4 90 1101.00 019.9

Sample ID: MBLK

Batch ID: 27411 TestNo: T291-94 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: PBS

RunNo: 61413

SeqNo: 804284

MBLKSampType: TestCode: CL_AASHTO

SW9056PR

Chloride 1.00ND

Qualifiers: H Holding times for preparation or analysis exceeded R RPD outside accepted recovery limits S Spike Recovery outside accepted recovery limits

TestCode: PH_AASHTO

11/24/2025

QC SUMMARY REPORT

2511167WO#:

Specialty Analytical

Sample ID: 2511167-001ADUP

Batch ID: R61424 TestNo: T289-91 Analysis Date: 11/19/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: pH Units

PQL

Client ID: TP-1, S-1 @ 5'

RunNo: 61424

SeqNo: 804440

DUPSampType: TestCode: PH_AASHTO pH 200 7.650 1.047.73

Qualifiers: H Holding times for preparation or analysis exceeded R RPD outside accepted recovery limits S Spike Recovery outside accepted recovery limits

TestCode: RESIST_AASHTO

11/24/2025

QC SUMMARY REPORT

2511167WO#:

Specialty Analytical

Sample ID: A2511133-001ADUP

Batch ID: R61455 TestNo: T288-91 Analysis Date: 11/19/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: ohm-cm

PQL

Client ID: BatchQC

RunNo: 61455

SeqNo: 804808

DUPSampType: TestCode: RESIST_AAS

Minimum Soil Resistivity 201.00 9300 9.2310200

Qualifiers: H Holding times for preparation or analysis exceeded R RPD outside accepted recovery limits S Spike Recovery outside accepted recovery limits

TestCode: SO4_AASHTO

11/24/2025

QC SUMMARY REPORT

2511167WO#:

Specialty Analytical

Sample ID: CCV

Batch ID: 27411 TestNo: T290-95 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61412

SeqNo: 804169

CCVSampType: TestCode: SO4_AASHT

SW9056PR

Sulfate 20.00 99.3 90 1100.250 019.9

Sample ID: CCV

Batch ID: 27411 TestNo: T290-95 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61412

SeqNo: 804173

CCVSampType: TestCode: SO4_AASHT

SW9056PR

Sulfate 20.00 99.6 90 1100.250 019.9

Sample ID: 2511169-001ADUP

Batch ID: 27411 TestNo: T290-95 Analysis Date: 11/18/2025

Prep Date: 11/18/2025

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: BatchQC

RunNo: 61412

SeqNo: 804176

DUPSampType: TestCode: SO4_AASHT

SW9056PR

Sulfate 20 RMI0.722 15.63 32.221.6

Sample ID: CCV

Batch ID: 27411 TestNo: T290-95 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61412

SeqNo: 804177

CCVSampType: TestCode: SO4_AASHT

SW9056PR

Sulfate 20.00 98.0 90 1100.250 019.6

Qualifiers: H Holding times for preparation or analysis exceeded R RPD outside accepted recovery limits S Spike Recovery outside accepted recovery limits

TestCode: SO4_AASHTO

11/24/2025

QC SUMMARY REPORT

2511167WO#:

Specialty Analytical

Sample ID: CCV

Batch ID: 27411 TestNo: T290-95 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: CCV

RunNo: 61412

SeqNo: 804177

CCVSampType: TestCode: SO4_AASHT

SW9056PR

Sample ID: MBLK

Batch ID: 27411 TestNo: T290-95 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: PBS

RunNo: 61412

SeqNo: 804178

MBLKSampType: TestCode: SO4_AASHT

SW9056PR

Sulfate 0.250ND

Sample ID: LCS

Batch ID: 27411 TestNo: T290-95 Analysis Date: 11/18/2025

Prep Date:

Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimit HighLimit RPDLimit Qual

Units: mg/Kg

PQL

Client ID: LCSS

RunNo: 61412

SeqNo: 804179

LCSSampType: TestCode: SO4_AASHT

SW9056PR

Sulfate 10.00 97.5 80 1200.250 09.75

Qualifiers: H Holding times for preparation or analysis exceeded R RPD outside accepted recovery limits S Spike Recovery outside accepted recovery limits

Sample Receipt Checklist

Specialty Analytical

9011 SE Jannsen Rd

Clackamas, Oregon 97015

Website: www.specialtyanalytical.com

TEL: 503-607-1331 FAX: 503-607-1336

Client Name: FEI Work Order Number 2511167

Date and Time Received: 11/17/2025 8:56:39 AM Received by: Josh PotterRcptNo: 1

Completed by: Reviewed by:

Carrier name: USPS

Custody seals intact on sample bottles? Yes No Not Present

Chain of custody present? Yes No

Chain of custody signed when relinquished and received? Yes No

Chain of custody agrees with sample labels? Yes No Not Present

Samples in proper container/bottle? Yes No

Sample containers intact? Yes No

Sufficient sample volume for indicated test? Yes No

All samples received within holding time? Yes No

Was an attempt made to cool the samples? Yes No NA

Yes No No VialsWater - Were bubbles absent in VOC vials?

Adjusted? Checked by

Any No and/or NA (not applicable) response must be detailed in the comments section below.

Are matrices correctly identified on Chain of custody? Yes No

Custody Seals present? Yes No

Sample Tags Present? Yes No

Sample Tags Listed on COC? Yes No

Completed Date: 11/17/2025 8:59:29 AM Reviewed Date: 11/17/2025 9:47:21 AM

Is it clear what analyses were requested? Yes No

Were correct preservatives used and noted? Yes No NA

Were container lables complete (ID, Pres, Date)? Yes No

All samples received at a temp. of > 0° C to 6.0° C? Yes No NA

Response when temperature is outside of range:

Preservative added to bottles:

Sample Temp. taken and recorded upon receipt? Yes No ºC18.8To

Yes No NAWater - Was there Chlorine Present?

Yes No NAWater - pH acceptable upon receipt?

Are Samples considered acceptable? Yes No

Traffic Report or Packing Lists present? Yes No

Air Bill Sticker Not PresentAirbill or Sticker?

Airbill No:

Tag Numbers:

Intact Broken LeakingSample Condition?

Case Number: SDG: SAS:

Sample Receipt Checklist

Specialty Analytical

9011 SE Jannsen Rd

Clackamas, Oregon 97015

Website: www.specialtyanalytical.com

TEL: 503-607-1331 FAX: 503-607-1336

Client Contacted? Yes No NA Person Contacted:

Contact Mode: Phone: Fax: Email: In Person:

Client Instructions:

Date Contacted: Contacted By:

Regarding:

Comments:

CorrectiveAction:

11/24/2025

Definition Only

2511167

Date:

WO#:

Definitions:

Specialty Analytical

9011 SE Jannsen Rd

Clackamas, Oregon 97015

Website: www.specialtyanalytical.com

TEL: 503-607-1331 FAX: 503-607-1336

KEY TO FLAGS

A: This sample contains a Gasoline Range Organic not identified as a specific hydrocarbon product. The result was qualified against gasoline calibration standards.

A1: This sample contains a Diesel Range Organic not identified as a specific hydrocarbon product.

The result was qualified against diesel calibration standards.

A2: This sample contains a Lube Oil Range Organic not identified as a specific hydrocarbon product. The result was qualified against lube oil calibration standards.

A3: The results was determined to be Non-Detect based on hydrocarbon pattern recognition. The product was carry-over from another hydrocarbon type.

A4: The product appears to be aged or degraded.

B: The blank exhibited a positive result greater than the reporting limit for this compound.

BC: Sample concentration is >10x positive result in blank. Data is considered acceptable.

CL: Sample was found to contain chlorine and was treated with sodium thiosulfate.

CN: See Case Narrative.

E: Result exceeds the calibration range for this compound. The result should be considered an estimate.

F: The positive result for this hydrocarbon is due to single component contamination. The product does not match any hydrocarbon in the fuels library.

FS: Follow-up testing is suggested.

G: Result may be biased high due to biogenic interferences. Clean up is recommended.

H: Sample was analyzed outside recommended holding time.

HT: At client’s request, samples was analyzed outside of recommended holding time.

2511167

Date:

WO#:

Definitions:

Specialty Analytical

9011 SE Jannsen Rd

Clackamas, Oregon 97015

Website: www.specialtyanalytical.com

TEL: 503-607-1331 FAX: 503-607-1336

HP: Sample was analyzed outside recommended holding time due to VOA having pH >2.

J: The results for this analyte is between the MDL and the PQL and should be considered an estimated concentration.

K: Diesel result is biased high due to amount of Oil contained in the sample.

L: Diesel result is biased high due to amount of Gasoline contained in the sample.

M: Oil result is biased high due to amount of Diesel contained in the sample.

N : Gasoline result is biased high due to amount of Diesel contained in the sample.

MC: Sample concentration is greater than 4x the spiked value, the spiked value is considered insignificant.

MI : Result is outside control limits due to matrix interference.

NH: Sample matrix is non-homogeneous

MSA: Value determined by Method of Standard Addition.

O: Laboratory Control Standard (LCS) exceeded laboratory control limits but meets CCV criteria.

Data meets EPA requirements.

Q: Detection levels elevated due to sample matrix.

R: RPD control limits were exceeded

RF : Duplicate failed due to result being at or near the method-reporting limit.

RP: Matrix spike values exceed established QC limits; post digestion spike is in control.

S: Recovery is outside control limits.

SC: CCV or LCS exceeded high recovery control limits, but associated samples are non-detect. Data

2511167

Date:

WO#:

Definitions:

Specialty Analytical

9011 SE Jannsen Rd

Clackamas, Oregon 97015

Website: www.specialtyanalytical.com

TEL: 503-607-1331 FAX: 503-607-1336

meets EPA requirements.

SL: LCS exceeded recovery control limits, but associated MS/MSD passing. Data meets EPA requirements.

SV: CCV exceded low recovery control limits. ND as reported evaluated using EPA method 8260D section 11.4.3.2

TA: Sample treated with ascorbic acid for the removal of thiocyanates.

TS: Sample treated with Sodium Sulfite for the removal of chlorine.

Appendix C Calculation Package

Seismic Evaluation

Lateral Earth Pressure Coefficients

Project: Ashland WWTP Headworks Upgrade Project Description: Lateral earth pressure coefficients Project No: D4027000 Prepared By: Jithin Nair

References:

American Association of State Highway and Transportation Officials (2020). AASHTO LRFD Bridge Design Specifications, Customary Units, 9th Edition.

Variables in blue are input variables, values outlined and in yellow are results of interest.

Backfill/Soil Profile Information

≔γbackfill ⋅130 pcf Unit weight of compacted backfill material

≔ϕbackfill ⋅34 deg Friction angle of compacted backfill material

≔γwater ⋅62.4 pcf Unit weight of water

≔β ⋅0 deg Back slope of backfill material measured from horizontal axis

≔θwall ⋅0 deg Slope of the abutment wall, measured from vertical axis

≔δwall =―――― ⋅2 ϕbackfill

22.67 deg Assumed half of friction angle

Seismic Variables

≔PGAMCE ⋅0.4 g peak Ground Acceleration

≔kv 0 Vertical Seismic Coefficient

≔kh ((PGA)) ――PGA 2 g

Horizontal Seismic Coefficient

≔ψ ⎛⎝ ,kh kv⎞⎠ atan kh -1 kv

≔khMCE =kh ⎛⎝PGAMCE⎞⎠ 0.2

≔ψMCE =ψ ⎛⎝ ,khMCE kv⎞⎠ 0.2

Lateral Earth Pressure Coefficient

At rest earth pressure

≔KO ((ϕ)) -1 sin ((ϕ))

Static active earth pressure coefficient

≔KA ⎛⎝ ,,,ϕ θ δwall β⎞⎠ ――――――――――――――――――― ((cos (( -ϕ θ))))2

⋅⋅((cos ((θ))))2 cos ⎛⎝ +θ δwall⎞⎠ +1

⋅sin ⎛⎝ +ϕ δwall⎞⎠ sin (( -ϕ β)) ⋅cos ⎛⎝ +θ δwall⎞⎠ cos (( -θ β))

Static passive earth pressure coefficient

≔KP ⎛⎝ ,,,ϕ θ δwall β⎞⎠ ――――――――――――――――――cos (( +ϕ θ))

⋅⋅cos ((θ)) cos ⎛⎝ -δwall θ⎞⎠ -1

⋅sin ⎛⎝ +δwall ϕ⎞⎠ sin (( +ϕ β)) ⋅cos ⎛⎝ -δwall θ⎞⎠ cos (( -β θ))

Seismic active earth pressure coefficient

≔KAE ⎛⎝ ,,,,ϕ θ δwall β ψ⎞⎠ ―――――――――――――――――――――――― ((cos (( --ϕ θ ψ))))2

⋅⋅⋅…