Geotechnical_Report_ATCH_CSO.pdf

in

UJ

Date:

MARCH 6,2025

GEOTECHNICAL EXPLORATION

COMBINED SEWER

OVERFLOW SEPARATION

ATCHISON, KANSAS

UES Project No..

J045885.01

Prepared for:

AFFINIS CORP

OVERLAND PARK, KANSAS

SAFETY

TEAMWORK

RESPONSIVENESS

INTEGRITY

VALUE

EXCELLENCE

Prepared by:

GEOTECHNOLOGY, LLC DBA UES

OVERLAND PARK, KANSAS

V(O UESTM

March 6, 2025

Re:

Dear Mr. Briscoe:

Sincerely, UES

Sr: 18 Q S9s

Masck la, 202S MHMJAW:mhm

5055 Antioch Road | Overland Park, Kansas 66203 | Phone: (913) 438-1900 | Fax: (913) 438-1923 | teamues.com

We appreciate the opportunity to provide geotechnical services for this project. If you have questions regarding this report, or if we may be of any additional service to you, please contact the undersigned.

Environmental Geotechnical Engineering Materials Testing Field Inspections & Code Compliance Geophysical Technology

Geotechnology, LLC dba UES (UES) presents in this report the results of the geotechnical exploration completed for the referenced project. This report includes our project understanding, observed site conditions, conclusions and/or recommendations, and support data as given in the Table of Contents.

Matt McQuality, P.E.

Office Lead

Geotechnical Exploration Combined Sewer Overflow Separation Atchison, Kansas UES Project No. J045885.01

Mr. Samuel Briscoe, P.E.

Affinis Corp 8900 Indian Creek Parkway, Suite 450 Corporate Woods Building 6 Overland Park, Kansas 66210

2AnsPSgs-0NALCP$4“*/egaeaasct8" eNHMcor, NASENSe x

:Q.*.

VO UESTM

TABLE OF CONTENTS

1.0 Introduction

108.0 Limitations

FIGURES

APPENDICES

A B

Page

C D E F

2.0 Project Information

3.0 Geotechnical Exploration

4.0 Laboratory Testing

5.0 Subsurface Conditions...

5.1 Pavement Section

5.2 Stratigraphy

5.3 Groundwater

Environmental Geotechnical Engineering Materials Testing Field inspections & Code Compliance Geophysical Technology

Site Location and Topography Aerial Photograph of Site and Boring Locations

6.0 Conclusions and Recommendations

6.1 Features Impacting Excavation ..

6.2 Site Grading

6.3 Manholes

6.4 Temporary Excavations

6.5 Temporary Shoring

6.6 Dewatering

6.7 Seismicity

6.8 Lateral Earth Pressures

6.9 Corrosivity

7.0 Recommended Additional Services..

Important Information about This Geotechnical-Engineering Report Logs of Borings B-1 through -3

Boring Log: Terms and Symbols Summary of Laboratory Results and Laboratory Test Computation Sheets Corrosion Potential Test Results Pavement Core Photographs Geotechnical Design Value Computation Sheets

UES TM

Each boring was drilled using a track-mounted CME 55 rotary drill rig equipped with an approximate 4-inch outside-diameter (O.D.) core barrel and 4-inch O.D. solid stem augers.

Sampling of the overburden soils was accomplished at the depths indicated on the boring logs with 2-inch O.D. split-spoon or 3-inch O.D. thin-walled Shelby tube samplers, in general

3.0 GEOTECHNICAL EXPLORATION

The geotechnical exploration consisted of drilling three borings, designated as Borings B-1 through -3, at approximately the locations shown on Figure 2. The borings were located in areas accessible to the drill rig and free of utilities. A representative of UES estimated the boring locations using a handheld GPS device. The surface elevations at the boring locations, which are listed on the boring logs provided in Appendix B, were estimated using a USGS website. A licensed surveyor should measure the boring locations if accurate location data is required.

2.0 PROJECT INFORMATION

The overall project includes the separation of combined sanitary and storm sewers in Atchison, Kansas. The project area includes (1) 15th Street between Atchison Street on the north and an unnamed alley on the south and (2) 16th Street between Main Street on the south and an unnamed alley on the north. Planned improvements include approximately 1,250 lineal feet of storm sewer and eight (8) stormwater structures. Other than the backfilling of excavations, site grading is not anticipated. Details of the project are being developed.

Environmental Geotechnical Engineering Materials Testing Field Inspections & Code Compliance Geophysical Technology

The storm sewer improvements parallel two-lane, asphalt-paved streets in a residential neighborhood. The site location and general topography of the area as per the 2018 U.S.G.S.

map of the vicinity are shown on Figure 1.

The purposes of the geotechnical exploration were to evaluate the general subsurface profile and the engineering properties of the soil at the site, and to develop recommendations for the geotechnical aspects of the design and construction of the project as defined in our proposal. Our scope of services included three geotechnical borings, laboratory testing, engineering analyses, and preparation of draft and final reports.

1.0 INTRODUCTION

Geotechnology, LLC dba UES (UES) prepared this geotechnical exploration report for Affinis Corp (Affinis) for the design of storm sewer improvements in Atchison, Kansas. The services documented in this report were provided in general accordance with the scope of services described in UES's Proposal P045885.01, dated May 22, 2024. A representative of Affinis authorized our services by issuance of a Task Order last signed November 5, 2024.

GEOTECHNICAL EXPLORATION

COMBINED SEWER OVERLFOW SEPARATION

ATCHISON, KANSAS

MARCH 6, 2025 | UES PROJECT NO. J045885.01

An engineer from UES provided direction during the field exploration, observed drilling and sampling, assisted in obtaining samples, and prepared field logs of the material encountered. A professional engineer has edited the final boring logs to incorporate results of the laboratory tests.

The boring logs and related information depict subsurface conditions only at the specific locations and time where sampling was conducted. The passage of time could result in changes in conditions, interpreted to exist, at or between the locations where sampling was conducted.

accordance with the procedures outlined by ASTM D1586 and ASTM D1587, respectively.

Standard Penetration Tests (SPTs) using a split-spoon sampler were performed to obtain the N-value1 of the sampled material. Each borehole was backfilled with dry premix concrete and patched with quickset cement.

The results of the moisture content, Atterberg limits and unconfined compressive strength tests are presented on the boring logs; a tabular summary of these results and the corresponding laboratory computation sheets are presented in Appendix C. Corrosion potential test results are tabulated in Table 7 and included as Appendix D. Photographs of the pavement cores are presented in Appendix E.

4.0 LABORATORY TESTING

Laboratory testing was performed to estimate engineering and index properties of the sampled material. The following tests were performed (the corresponding ASTM standard, if applicable, is in parentheses):

Unless noted on the boring logs, the lines designating the changes between various strata represent approximate boundaries. The transition between materials could be gradual or could occur between recovered samples. The stratification given on the boring logs, or described herein, is for use by UES in its analyses and should not be used as the basis of design or construction cost estimates without realizing that there can be variation from that shown or described.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 | Project No. J045885.01

• Moisture content (ASTM D 2216)

• Atterberg limits, single-point (ASTM D 4318)

• Unconfined compressive strength (ASTM D 2166)

• Corrosion potential tests (i.e., sulfide, pH, oxidation/reduction potential, resistivity, chloride and sulfate)

1The Standard Penetration Test value, or N-value, is defined as the number of blows required to drive the split-spoon sampler 12 inches with a 140-pound hammer falling 30 inches. Since the split-spoon sampler is driven 18 inches or until refusal, the blows for the first 6 inches are for seating the sampler, and the number of blows for the final 12 inches is the N-value. Additionally, “refusal" of the split-spoon sampler occurs when the sampler is driven less than 6 inches with 50 blows of the hammer.

5.0 SUBSURFACE CONDITIONS

Table 1. Pavement Section Summary

Boring

5.1 Pavement Section

A summary of the pavement section at the boring locations is presented in Table 1.

B-1 B-2 B-3

5.2 Stratigraphy

Boring B-1 (15th Street and Atchison Street). Below the pavement section the stratigraphy consists of native, brown and gray, medium stiff to very stiff, lean clay some sand to a depth of approximately 12 feet underlain by dark gray and brown, very stiff, lean clay some sand, trace gravel to the 15-foot-depth of exploration. Auger refusal material was not encountered.

5.3 Groundwater

Groundwater levels observed at the borings during drilling are presented in Table 2. The presence or lack of groundwater levels might not represent present or future levels. Groundwater levels might vary substantially over time due to the effects of seasonal variation in precipitation, recharge, levels of nearby tributaries, or other factors not evident at the time of exploration.

Therefore, groundwater levels during construction or at other times in the life of the structures might differ than the levels indicated on the boring logs. Water might be trapped within permeable fill pockets, if present, and in utility trenches backfilled with clean rock.

Presented herein is a summary of the pavement section, stratigraphy and groundwater encountered at the boring locations. The boring logs should be reviewed for further description of the surface and subsurface conditions at the boring locations.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 | Project No. J045885.01

B-3 (16th Street and Main Street). Below the pavement section the stratigraphy consists of native, brown, stiff to very stiff, lean clay some sand to a depth of approximately 7 feet underlain by brown, medium dense, fine sand to a depth of approximately 9.5 feet underlain, in turn, by dark gray and brown, very stiff, lean clay some sand and gravel to a depth of approximately 12 feet.

Below the clay, medium dense, brown, fine sand occurs to a depth of approximately 14.5 feet underlain by weathered shale to the 15-foot-depth of exploration. Auger refusal material was not encountered.

B-2 (15th Street and Kansas Avenue). Below the pavement section the stratigraphy consists of fill to a depth of approximately 7 feet. The fill sampled included dark brown and brown fat clay, gravel and concrete fragments. Below the fill, the soil stratigraphy consisted of native, stiff, brown lean clay to a depth of approximately 12 feet underlain by stiff, brown, fat clay to the 15-foot-depth of exploration. Auger refusal material was not encountered.

Concrete, inches

Asphalt, inches

2.5 3.5 1.5

Brick, inches None 2.5

None

Crushed Rock, inches None None None

YO

Table 2. Groundwater Summary

Approx. Groundwater Level During Drilling Boring

Not Observed El 846.513.5

Sand. Sand strata was encountered in one boring. Sand might occur in unexplored areas of the site. Sand is collapsible. As discussed herein, shoring might be required for excavations in sand.

B-1 B-2 B-3

Groundwater. Groundwater was encountered in two of the borings. Dewatering should be provided to maintain groundwater at least 12 inches below the bottom of excavations to maintain a stable base for construction and to reduce instability of excavated slopes. Further discussion on dewatering is presented herein.

Surface Elevation El 9232 El 872 El 860

6.2 Site Grading

Suitable Fill Materials. On-site materials generated from excavations are expected to include fine-grained soil, sand and pieces of asphalt, concrete and brick. Fine-grained soil and sand are typically suitable for trench backfill provided the material is moisture conditioned and free of deleterious materials. Pieces of asphalt, concrete and brick should be processed to form a well-graded mixture with a maximum 2-inch particle size. Alternatively, pieces of asphalt, concrete and brick could be hauled of the site and properly disposed.

6.0 CONCLUSIONS AND RECOMMENDATIONS

UES should be allowed to review final plans to check that our recommendations have been correctly implemented and are applicable to final design. A discussion of the geotechnical features that might influence construction are presented in the following paragraphs.

Imported backfill should consist of lean, fine-grained soil (liquid limit less than 45) or well-graded crushed limestone with a 2-inch maximum particle size. Acceptable fill soils include non-organic materials designated as CL, CL-ML, ML, GM, GW and GW-GM in accordance with ASTM D 2487.

Frozen soils and soil with deleterious materials should not be used for trench backfill.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 | Project No. J045885.01

6.1 Features Impacting Excavation

Existing Fill. Fill was encountered in one boring. Fill and trench backfill likely occurs in unexplored areas of the site. Fill might extend to greater depths than those depicted on the boring logs. The composition of the fill could vary in unexplored locations. In the absence of documentation, fill and trench backfill should be considered uncontrolled and unstable. Unstable fill encountered in excavations could collapse. As discussed herein, shoring might be required for temporary excavations.

Elev.

El 913

Feet

2 Elevations herein are in feet and reference 1988 North American Vertical Datum (NAVD88)

Measured as a percent of the maximum unit weight as determined by the modified Proctor test (ASTM D 1557).

6.3 Manholes

Net Allowable Bearing Pressure. Manholes bearing on the natural soil and compacted fill may be designed for a net allowable bearing pressure of 1,500 pounds per square foot (psf). Areas or subgrades which exhibit soft or unstable characteristics should be overexcavated and backfilled with compacted well-graded crushed rock, lean concrete or concrete.

Collection and Disposal of Site Water. Control of surface runoff should be maintained in compliance with the rules and regulations set forth in the Federal Water Pollution Control Act.

Additionally, permits related to site grading activities and control of storm water during construction activities should be obtained from the applicable governmental jurisdiction(s).

Settlement of new manholes is expected to be less than 1/4 inch provided the manholes are proportioned and constructed as recommended herein. Estimated values of settlement contained in this report are based on our experience with projects of a similar nature. Consolidation tests and corresponding settlement calculations have not been made.

Pipe Bedding. Soft soil and disturbed soil subgrade areas should be replaced with compacted, well-graded crushed rock. Well-graded crushed rock should be used as the bedding material for pipes and sewer manholes. Loose material that accumulates in excavations should be removed prior to laying pipe or placing concrete or rock base for manholes.

Subgrade Protection. Drainage of the construction areas should be provided to protect excavations and structure subgrades from the detrimental effects of weather conditions during construction. Finished subgrades and structure excavations should be kept free of standing water.

Concrete should be placed in foundation excavations the same day they are completed.

Trench Backfill. Settlement of trench backfill can result in unsightly depressions and localized failures. The magnitude of settlement can be substantially reduced by mechanical compaction of the trench backfill. Clean rock should not be used for trench backfill. Clean rock can collect water which can soften the underlying fine-grained soils or result in the migration of fines and loss of subgrade support.

Trench Backfill Placement. Trench backfill should be placed in uniform lifts and compacted. The loose lift thickness should not exceed 6 inches. The fill should be systematically compacted to the levels given in Table 3. The soil should be placed at moisture contents compatible with the required unit weight. Depending on the soil moisture at the time of construction, aeration or wetting might be required to achieve compaction. Deleterious material should not be included in backfill, and backfill should not be placed on soft materials or frozen ground.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 Project No. J045885.01

Table 3. Compaction Summary Category

Fine-Grained Soil Well-Graded Crushed Limestone

Minimum Compaction 90% 95%

Table 4. Temporary Slopes Per OSHA Regulations a b

1V:1.5H or flatter;

benching not permitted

6.5 Temporary Shoring

Excavated temporary slopes might not be feasible at all locations and temporary shoring systems might be required. While different temporary shoring types and configurations can be used, the

6.4 Temporary Excavations

If site geometry permits, it might be possible to lay slopes back to a stable configuration.

Temporary excavation slopes should be consistent with safety regulations. Worker safety and classification of soil type is the responsibility of the contractor. The materials encountered during excavations for the proposed project are anticipated to consist of fill of unknown origin; medium stiff to very stiff clay, and sand. Native medium stiff to very stiff clay soil can generally be classified as OSHA Type B soil. Fill of unknown origin and sand should be considered OSHA Type C soil.

Temporary slopes per OSHA regulations for these soil types are presented in Table 4.

Temporary slopes left open might undergo sloughing and result in an unstable situation. The contractor should evaluate stability and failure consequences before open cut slopes are made.

Minor sloughing of open face slopes might occur. If the slope is expected to remain open for an extended time, an impermeable membrane covering the slopes could be considered as a means to reduce the potential for slope degradation and instability. It is important to note that soils encountered in the construction excavations might vary across the sites, and that even if the OSHA criteria are used, there is a potential for slope failure.

The contractor should be aware that excavation depths and inclinations (including adjacent existing slopes) should not exceed those specified in local, state or federal safety regulations, e.g., OSHA Health and Safety Standards for Excavations, 29 CFR, or successor regulations.

Such regulations are strictly enforced and, if not followed, the contractor, or earthwork or utility subcontractors could be subjected to substantial penalties. Construction site safety is the sole responsibility of the contractor, who shall also be solely responsible for the means, methods and sequencing of construction operations.

Uplift Resistance. Uplift loads can be resisted by the buoyant weight of the manhole and frictional resistance between the manhole exterior and compacted backfill placed against the manhole. For compacted backfill placed against a manhole, an allowable frictional resistance value of 500 psf may be used. The frictional resistance in the top 36 inches of compacted fill should be neglected due to seasonal variations in moisture and frost penetration. The friction value provided in this section does not need to be reduced for the portion of a structure below groundwater.

Sloping or benching for excavations greater than 20 feet deep shall be designed by a registered professional engineer.

Includes excavations terminating in Type C soil.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 | Project No. J045885.01

Slope Inclination3

1V:1H or flatter Soil Type

B

_ _ _ CP_________

Soil Slopes Below Groundwater

(Regardless of soil type)

Y/O

Trench Boxes. Trench boxes are steel or aluminum structures used for protecting personnel performing duties within a trench. Trench boxes are customarily constructed with sidewalls of varying thicknesses, are held apart by internal steel or aluminum bracing, and are placed within a trench after excavation. Trench boxes are typically limited to excavation depths of 10 to 12 feet.

Since voids typically occur between the sidewalls of the trench box and the edge of the excavation, trench boxes do not prevent collapse of excavation sidewalls. In addition, trench boxes are not recommended for excavations adjacent to structures sensitive to movement.

6.6 Dewatering

Depending on the level of groundwater at the time of construction, it might be necessary to dewater excavations to enable construction to be carried out under relatively dry conditions, to prevent subgrade disturbance, and to provide stability of excavated slopes. Groundwater should be lowered to at least 12 inches below excavation bottoms. It is anticipated that groundwater in excavations in fine-grained soil can be controlled by use of sumps and pumps. Control of groundwater in excavations that extend into the underlying sand might require single or multistage well points using centrifugal, vacuum or jet-eductor pumps. Selection of a dewatering approach depends on the season of the year, volume of water anticipated, type of subgrade soils, proximity of source and other factors. If sumps cannot control the groundwater seepage, UES should be contacted to review the method of dewatering proposed by the contractor. Dewatering systems should be designed by a contractor with experience in similar soil conditions.

more common types that are applicable to this site are trench boxes, and soldier pile and lagging.

Brief discussions of potential temporary shoring methods are presented in the following paragraphs. Other methods of temporary shoring, however, may also be considered. Temporary shoring installed adjacent to structures sensitive to movement should be designed for at-rest lateral earth pressures. Temporary shoring permitted to tilt out approximately 0.5 percent of the depth of the excavation may be designed for active lateral earth pressures.

Soldier Piles and Lagging. Construction of soldier piles involves placing steel H-piles in predrilled holes that are subsequently backfilled with flowable fill or lean concrete. As the excavation proceeds downward, timber lagging or steel sheeting is installed between the exposed H-piles to restrain the exposed cohesive soil. Additional lateral resistance can be obtained by installing internal bracing or tiebacks. Voids between the timber lagging or steel sheeting should be filled.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 | Project No. J045885.01

6.7 Seismic Design Coefficients

Per the general procedures of Section 1613 of IBC 2021, the soil profile at the project site can be defined as Class D - Stiff Soil. Based on the web application Seismic Design Maps prepared by the Structural Engineers Association of California (SEAOC) and the California’s Office of Statewide Health Planning and Development (OSHPD) using the latitude and longitude coordinates of the project site, the seismic parameters that can be used for this project are given in Table 5.

Y(O Table 5. Seismic Parameters

Seismic Site Class

D - Stiff Soil

Table 6. Lateral Earth Pressures for Horizontal Ground Surfaces - Drained Condition

Description of Backfill

Where:

Design Soil Lateral Load (psf per foot of depth)

The given values assume that hydrostatic pressures will not develop behind the walls and that the wall backfill will be compacted as previously recommended. Therefore, below-grade walls should have perforations to allow for dissipation of water pressure against the walls. Undrained walls might be subjected to additional pressures from groundwater, perched water, or surface water infiltration.

Design values are provided in Table 6 for lateral loads on below-grade walls. If tilting or deflection is not tolerable, at-rest earth pressures should be assumed. Computation sheets for the geotechnical design values are presented as Appendix F.

h = depth below adjacent grade, feet q = surcharge load, psf

For the equations in Table 6 to be valid for crushed stone backfill, the backfill should be placed in a wedge extending upward and away from the edge of the footings at an angle ‘p’ of 45 degrees or flatter (see the following figure). If crushed stone is to be placed within a wedge at an angle 'p' of more than 45 degrees from the bottom of the structure, the values for fine-grained soil provided in Table 6 should be used

6.8 Lateral Earth Pressures

Below-grade walls should be designed to withstand lateral earth pressures caused by adjacent soil and surcharge load. Design lateral pressures from surcharge loads should be added to the lateral earth pressure load. Lateral earth pressures can vary with wall restraint conditions, type of backfill and method of backfill compaction.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 | Project No. J045885.01

At-rest 65h + 0.55q 56h + 0.40q

Si (g)

0.061

SDI

(g)

0.098

SMS

(g)

0.143

SMI

(g)

0.147

SDS

(g)

0.095

Active 45h + 0.38q 35h + 0.25q

Ss (g)

0.089

_______ Fine-Grained Soil_______ Well-Graded Crushed Stone (GW)

V/O

" IT-ETATF"

Table 7. Summary of Corrosion Potential Test Results

Sample pH

225 NDB-2,10 feet 5.8 19 476507 ND - Not detected

Table 8. DIPRA Point Total

Boring Location Sample Description

B-2 Stiff, brown, lean CLAY - (CL) 10 11

15th Street south of Kansas Avenue

Chloride, mg/kg

Sulfide, mg/kg

Depth, Feet

Sulfate, mg/kg

Resistivity, ohms-cm

Moisture, percent

DIPRA

Point Total

7.0 RECOMMENDED ADDITIONAL SERVICES

The conclusions and recommendations given in this report are based on: UES’s understanding of the proposed design and construction, as outlined in this report; site observations; interpretation of the exploration data; and our experience. Since the intent of the design recommendations is best understood by UES, we recommend that UES be included in the final design and construction process and be retained to review the project plans and specifications to confirm that the

The DIPRA point total for the tested sample is presented in Table 8; the tested sample had a point total of more than 10. Consequently, protective measures such as cathodic protection or a proprietary coating for buried metal features are warranted based on the results of the analytical tests.

6.9 Corrosivity

Iron Pipe. The Ductile Iron Pipe Association (DIPRA) 10-point corrosion potential evaluation system was used to assess the corrosion potential of a soil sampled collected at Boring B-2. The evaluation procedure requires the following analytical tests: soil resistivity, pH, oxidation-reduction potential, sulfides and moisture. For a given soil sample, each parameter is evaluated and assigned points for all five areas. The points are totaled and if the sum is 10 or more, the soil is considered potentially corrosive to iron pipe, which would warrant protective measures. Corrosion potential test results are summarized in Table 7.

Cement. Based on the results of the analytical tests, below-grade concrete will be exposed to a moderate sulfate condition and Type II cement should be used.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 Project No. J045885.01

Redox Potential, mv 231.9

P

JL

Y/O

The conclusions or recommendations presented in this report should not be used without UES’s review and assessment if the nature, design, or location of the facilities is changed, if there is a

Our scope of service for this phase of the project did not include any environmental assessment or investigation for the presence or absence of wetlands or hazardous or toxic materials in the soil, surface water, groundwater, or air, on or below or around this site. Any statements in this report or on the boring logs regarding odors noted or unusual or suspicious items or conditions observed are strictly for the information of our client. Our scope of service did not include an assessment of the effects of flooding and erosion of creeks or rivers adjacent to or on the project site.

The analyses, conclusions, and recommendations contained in this report are based on the data obtained from the subsurface exploration. The field exploration methods used indicate subsurface conditions only at the specific locations where samples were obtained, only at the time they were obtained, and only to the depths penetrated. Consequently, subsurface conditions may vary gradually, abruptly, and/or nonlinearly between sample locations and/or intervals.

Since actual subsurface conditions between boring locations may vary from those encountered in the borings, our design recommendations are subject to adjustment in the field based on the subsurface conditions encountered during construction. Therefore, we recommend that UES be retained to provide construction observation services as a continuation of the design process to confirm the recommendations in this report and to revise them accordingly to accommodate differing subsurface conditions. Construction observation is intended to enhance compliance with project plans and specifications. It is not insurance, nor does it constitute a warranty or guarantee of any type. Regardless of construction observation, contractors, suppliers, and others are solely responsible for the quality of their work and for adhering to plans and specifications.

UES has attempted to conduct the services reported herein in a manner consistent with that level of care and skill ordinarily exercised by members of the profession currently practicing in the same locality and under similar conditions. The recommendations and conclusions contained in this report are professional opinions. The report is not a bidding document and should not be used for that purpose.

recommendations given in this report have been correctly implemented. We recommend that UES be retained to participate in prebid and preconstruction conferences to reduce the risk of misinterpretation of the conclusions and recommendations in this report relative to the proposed construction of the subject project.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 j Project No. J045885.01

8.0 LIMITATIONS

This report has been prepared on behalf of, and for the exclusive use of, the client for specific application to the named project as described herein. If this report is provided to other parties, it should be provided in its entirety with all supplementary information. In addition, the client should make it clear that the information is provided for factual data only, and not as a warranty of subsurface conditions presented in this report.

V/O substantial lapse in time between the submittal of this report and the start of work at the site, or if there is a substantial interruption or delay during work at the site. If changes are contemplated or delays occur, UES must be allowed to review them to assess their impact on the findings, conclusions, and/or design recommendations given in this report. UES will not be responsible for any claims, damages, or liability associated with any other party’s interpretations of the subsurface data or with reuse of the subsurface data or engineering analyses in this report.

A copy of "Important Information about This Geotechnical-Engineering Report" that is published by the Geotechnical Business Council (GBC) of the Geoprofessional Business Association (GBA) is included in Appendix A for your review. The publication discusses some other limitations, as well as ways to manage risk associated with subsurface conditions.

The recommendations included in this report have been based in part on assumptions about variations in site stratigraphy that may be evaluated further during sewer construction. UES should be retained to perform construction observation and continue its geotechnical engineering service using observational methods. UES cannot assume liability for the adequacy of its recommendations when they are used in the field without UES being retained to observe construction.

Geotechnical Report Combined Sewer Overflow Separation | Atchison, Kansas March 6, 2025 | Project No. J045885.01

- V CWUV)P) 1 \ - (/ IoNl (l( d ('■ HARPER DRJJ C J A

HARPER DRT9N J(250

L)Wes gf^IDGE DRI /

8 9 . k

.1 - ’ 5.5 V| / s' N I

MSTVe1)i !iite| LSTLy■ X2)\ J 2 ,r.

j

DIVISION ST1.60% ___DIVISION ST^-

■": 1 unuun.i I, r

4 J

1 2 । MOUND:ST - dJ.*

B. f 7Co* 7 iFXnJ

V k) fell \KEARNEY ST '

—=T 31— —I — — “ARAM"“T —

- Y i|P j J LARAMIEST J : I-4 770 Wo 1 in

— ^PARALtED ST - Z.Z i A,ATCHISONISTSTATCHISON .6JTTTE1) ssama cr rr -33 ux2 ! 2,SANTA FE ST

I71 e &CT....I_____ T " ATC =sun"AnE)

O A SITE CT\ / )

{ MAIN ST I‘_MAINST B

—sobf ll59;8 C i

IA I

{1V aeeC

)if Mount SaintScholastica CemV • i

II

8 s . |\ V D 2I t%. ' 1 k ’

GREEN ST% p V.V GREEN STU22 22 at-boe \0 o; 20D /Pa.Y .0 v -05

_J Si

2,000 4,0000

SCALE IN FEET

Ck'd By: MHM

Date: 1-16-25

VO UESTM

-N-

FIGURE 1

App’vd By: JAW

Date: 1-21-25

Drawn By: WAH

Date: 12-13-24

-O u O i2

O t-C

KEARNEY ST* I 2

Project Number J045885.01

X

- ) LST

\ ; Oak Hill Ce m

C

3 ©

X

RILEY^ST

Vs 33

SITE LOCATION AND

TOPOGRAPHY

O -O’

8—1.

A

’ F =-o-z

S

1 (O

TSI f I | 15) maIN’ST e j

MOUND ST

Combined Sewer Overflow Separation Atchison, Kansas t

7 AT )

1 1II 2G

( ; t

: —Pm nuceh ATCmISONL 1 o-iig

FC

T asome?”

1.

A ; 11

I

1e1

NUST

. ’1

I . '

X ' r i /

• 3 ■ M2

NOTES

1. Plan adapted from 7.5 minute U.S.G.S.

maps for Atchison West and Atchison East, Kansas quadrangles, last revised in 2018.

294TH RDTIT

L X yi

MSTSD

we i

. eo

CT -jCTr ) in a

C

E11

10 4 -

4 ,E0U ’ a "zE ■

I|73

IU

OAKWOOD DR

P — " X — val"h)0

Wh

। < .A..eone=ce=iP=% mauosuunrontes g

’ o.

Ma 1

3---5-- ATCHISON

S

7 1 s

_____ ATCHISONSTREET—•—

B h i B-1eV

ALLEY

': ■ r t, ..J

Uur

. SANTA FE STREET - -------- 10• • £

•I0l \9

If ALLEY I io' r 0 ■

Ef i = rPre Al LEY,——

"N— r *1\ e LW 8

ICOMMERCIAL STREET %— • —

Lr

ALLEY 09

n B-3« —A t—== — • —

NIN STREET (HWY 7) /

L. 72---------*r 1

0 250 500

SCALE IN FEET

VO UESTM

LEGEND

FIGURE 2

Boring Location

Proposed Project Alignment

Storm Sewer Inlet

App’vd By: JAW

Date: 1-21-25

Drawn By: WAH

Date: 12-13-24

2019/2020 Dam 6 Separation Project Storm Sewer System.

Project Number J045885.01

Ck'd By: MHM

Date: 1-16-25

AERIAL PHOTOGRAPH OF

SITE AND BORING LOCATIONS

------- Existing Separate Sewer

------- Existing Combined Sewer

I I

I

I

— g-r

£ to

“II

I t

=l=

"s -ar

I

LU

(X s

• 1

LU

ID

f ft*I a- • d

Combined Sewer Overflow Separation Atchison, Kansas

.u . u atrW

X X

I s I I

NOTES

1. Plan adapted from an April 6, 2020 aerial photograph courtesy of Google Earth and an undated drawing titled "Exhibit 3 - 14th Street Sewershed Separation (Phase 3)", supplied by the client.

2. Borings were located in the field utilizing a hand-held GPS device.

.1 ST 2T FheDF\

• i r i R

I I I I E I

I

— V

Mr * ‘

—X----- X

X

Acid

5 o

\ B-2©

L — -

KANSAS AVENUE

. ‘ . .... - ‘h “ •, i । s t I I I I I I

X

X

APPENDIX A

Important Information about This Geotechnical-Engineering Report

Geotechnical Report

Geotechnical-Engineering Report prepared solely for the client. No one except you should rely on study. Do not rely on a geotechnical-engineering report whose

Geotechnical engineers consider many unique, project-specific data and then apply their professional judgment to render the geotechnical engineer who conducted the study specifically unanticipated conditions.

• the function of the proposed structure, as when it’s changed engineer who developed your report cannot assume

• the elevation, configuration, location, orientation, or weight geotechnical-construction observation required to confirm the recommendations’ applicability.

Important Information about This

Subsurface problems are a principal cause of construction delays, cost overruns, claims, and disputes.

While you cannot eliminate all such risks, you can manage them. The following information is provided to help.

factors when establishing the scope of a study. Typical factors include: the client’s goals, objectives, and risk-management preferences; the general nature of the structure involved, its size, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless

Typical changes that can erode the reliability of an existing geotechnical-engineering report include those that affect:

As a general rule, always inform your geotechnical engineer of project changes—even minor ones-and request an

Geotechnical Services Are Performed for Specific Purposes, Persons, and Projects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical-engineering study conducted for a civil engineer may not fulfill the needs of a constructor — a construction contractor — or even another civil engineer. Because each geotechnical- engineering study is unique, each geotechnical-engineering report is unique, an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ — sometimes significantly — from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide geotechnical-construction observation is the most effective method of managing the risks associated with assessment of their impact. Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed.

of the proposed structure;

• the composition of the design team; or

• project ownership.

Geotechnical Engineers Base Each Report on a Unique Set of Project-Specific Factors indicates otherwise, do not rely on a geotechnical-engineering report that was:

• not prepared for you;

• not prepared for your project;

• not prepared for the specific site explored; or

• completed before important project changes were made.

adequacy may have been affected by: the passage of time;

man-made events, such as construction on or adjacent to the site; or natural events, such as floods, droughts, earthquakes, or groundwater fluctuations. Contact the geotechnical engineer before applying this report to determine if it is still reliable. A minor amount of additional testing or analysis could prevent major problems.

from a parking garage to an office building, or from a light industrial plant to a refrigerated warehouse;

this geotechnical-engineering report without first conferring with the geotechnical engineer who prepared it. And no one

— not even you — should apply this report for any purpose or project except the one originally contemplated.

responsibility or liability for the report’s confirmation-dependent recommendations if that engineer does not perform the

A Report’s Recommendations Are Not Final Do not overrely on the confirmation-dependent recommendations included in your report. Confirmation dependent recommendations are not final, because geotechnical engineers develop them principally from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual subsurface conditions revealed during construction. The geotechnical

A Geotechnical-Engineering Report Is Subject to Misinterpretation Other design-team members’ misinterpretation of geotechnical-engineering reports has resulted in costly

Subsurface Conditions Can Change A geotechnical-engineering report is based on conditions that existed at the time the geotechnical engineer performed the

Read the Full Report Serious problems have occurred because those relying on a geotechnical-engineering report did not read it all. Do not rely on an executive summary. Do not read selected elements only.

Most Geotechnical Findings Are Professional Opinions Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. Geotechnical engineers review field and laboratory

GEL,

problems. Confront that risk by having your geotechnical engineer confer with appropriate members of the design team after submitting the report. Also retain your geotechnical engineer to review pertinent elements of the design team’s plans and specifications. Constructors can also misinterpret a geotechnical-engineering report. Confront that risk by having your geotechnical engineer participate in prebid and preconstruction conferences, and by providing geotechnical construction observation.

Read Responsibility Provisions Closely Some clients, design professionals, and constructors fail to recognize that geotechnical engineering is far less exact than other engineering disciplines. This lack of understanding has created unrealistic expectations that have led to disappointments, claims, and disputes. To help reduce the risk of such outcomes, geotechnical engineers commonly include a variety of explanatory provisions in their reports. Sometimes labeled “limitations,” many of these provisions indicate where geotechnical engineers’ responsibilities begin and end, to help

Environmental Concerns Are Not Covered The equipment, techniques, and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical study. For that reason, a geotechnical-engineering report does not usually relate any environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated environmental problems have led to numerous project failures. If you have not yet obtained your own environmental information, ask your geotechnical consultant for risk-management guidance. Do not rely on an environmental report prepared for someone else.

others recognize their own responsibilities and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly.

Rely, on Your GBC-Member Geotechnical Engineer for Additional Assistance Membership in the Geotechnical Business Council of the Geoprofessional Business Association exposes geotechnical engineers to a wide array of risk-confrontation techniques that can be of genuine benefit for everyone involved with a construction project. Confer with you GBC-Member geotechnical engineer for more information.

Do Not Redraw the Engineer’s Logs Geotechnical engineers prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical-engineering report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk.

Obtain Professional Assistance To Deal with Mold Diverse strategies can be applied during building design, construction, operation, and maintenance to prevent significant amounts of mold from growing on indoor surfaces.

To be effective, all such strategies should be devised for the express purpose of mold prevention, integrated into a comprehensive plan, and executed with diligent oversight by a professional mold-prevention consultant. Because just a small amount of water or moisture can lead to the development of severe mold infestations, many mold- prevention strategies focus on keeping building surfaces dry. While groundwater, water infiltration, and similar issues may have been addressed as part of the geotechnical- engineering study whose findings are conveyed in this report, the geotechnical engineer in charge of this project is not a mold prevention consultant;

none of the services performed in connection with the geotechnical engineer’s study were designed or conducted for the purpose of mold prevention. Proper implementation of the recommendations conveyed in this report will not of itself be sufficient to prevent mold from growing in or on the structure involved.

Give Constructors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can make constructors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation.

To help prevent costly problems, give constructors the complete geotechnical-engineering report, but preface it with a clearly written letter of transmittal. In that letter, advise constructors that the report was not prepared for purposes of bid development and that the report’s accuracy is limited;

encourage them to confer with the geotechnical engineer who prepared the report (a modest fee may be required) and/ or to conduct additional study to obtain the specific types of information they need or prefer. A prebid conference can also be valuable. Be sure constructors have sufficient time to perform additional study. Only then might you be in a position to give constructors the best information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions.

GEOTECHNICAL

BUSINESS COUNCIL

of the Geoprofessional Business Association

8811 Colesville Road/Suite G106, Silver Spring, MD 20910 Telephone: 301/565-2733 Facsimile: 301/589-2017 e-mail: info@geoprofessional.org www.geoprofessional.org

Copyright 2015 by Geoprofessional Business Association (GBA). Duplication, reproduction, or copying of this document, or its contents, in whole or in part, by any means whatsoever, is strictly prohibited, except with GBA’s specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of GBA, and only for purposes of scholarly research or book review. Only members of GBA may use this document as a complement to or as an element of a geotechnical-engineering report. Any other firm, individual, or other entity that so uses this document without being a GBA member could be commiting negligent or intentional (fraudulent) misrepresentation.

Y(O

APPENDIX B

Logs of Borings B-1 through -3 Boring Log: Terms and Symbols

Geotechnical Report

SHEAR STRENGTH, tsf 12/5/24923Surface Elevation Completion Date: O - QU/2 □ - PP/2A - UU/2

1,5 20 250.5 1,0Datum NAVD88 1

STANDARD PENETRATION RESISTANCE

DESCRIPTION OF MATERIAL

ILLPL I02 oQ 30 40 5010 20

ASPHALT - 2.5 inches

I IASS13-3-4

• - OST2103

5—

ASS33-4-4

$5 ASS44-5-6

III CL

Vl0zSo - 10-u%FO

X SS55-8-12a.

2 22FO - 15 Boring terminated at 15 feet.

oz L2 — —Tt---- 20-nU.

Check by: MHM App’vdby: JAW DRILLING DATAGROUNDWATER DATA Date: 1-21-25Date: 1/16/25

4" AUGER __ HOLLOW STEM V/UESWASHBORING FROM___FEETENCOUNTERED AT 10 FEET Y TM

DJT DRILLER RAW LOGGER

CME 55TRK DRILL RIG

HAMMER TYPE Auto

REMARKS:

LOG OF BORING: B-1

Project No. J045885.01

Drawn by: RAW Date: 12/6/24

O

Q

WO — (

Combined Sewer Overflow Separation

Atchison, Kansas

X — Q.

LU

Q. <

LU

CLAY - dark gray and brown, very stiff, lean, some sand, trace gravel - CL

Ul

0) L n.

0)LU

II

LL

CONCRETE -10 inches CLAY - brown and gray, medium stiff to very stiff, lean, some sand - (CL)

O I Q.

a O ig 83z

O J co —

(ASTM D 1586)

A N-VALUE (BLOWS PER FOOT)

WATER CONTENT, %

< 0

29 LU D

( C LU e Ka O CD d LU

00 UU— 22

=!O O c

(. LU

Z C uO

LU 0-

$2 95

E5% 001 1110 >

220 280 — - III

Zm0

DEL

>nQ 20O

2«

O

872 12/5/24Surface Elevation Completion Date: A - UU/2 O - QU/2 □ - PP/2

0,5 10 1,5 2,0 25Datum NAVD88

352o O — inEu Z mQ

DESCRIPTION OF MATERIAL WATER CONTENT, %

OZ PLH ILLO 10 20 30 40 50i

ASPHALT - 3.5 inches BRICK - 2.5 inches

4-3-5 SS1 A

A2-1-2 SS2

5-

A7-3-3 SS3

CLAY - brown, stiff, lean - (CL)

- -O- 1103 ST42i 0 m Z

MO - 10-

LU —

u% CLAY - brown, stiff, fat - CHFO

O-TI A3-4-5 SS5CL2

15 Boring terminated at 15 feet.

Z200

E2 r — - 20- W —0

Check by: MHM App’vd by: JAW

GROUNDWATER DATA DRILLING DATA

Date: 1-21-25Date: 1/16/25

4" AUGER __ HOLLOW STEM

/UESWASHBORING FROM___FEET TM

RAW LOGGERDJT DRILLER

CME 55TRK DRILL RIG

HAMMER TYPE Auto

REMARKS:

LOG OF BORING: B-2

Project No. J045885.01

Drawn by: RAW Date: 12/6/24

O

Combined Sewer Overflow Separation

Atchison, Kansas

EQ

LU

LU

L.

Q < w

GO

LU•

Q

8.

.CONCRETE - 2 inches________ FILL - dark brown and brown fat clay, some gravel and concrete fragments poor sample recovery

5 a O Z

S

Q

LU

O T Q. s

X FREE WATER NOT

ENCOUNTERED DURING DRILLING

STANDARD PENETRATION RESISTANCE

(ASTM D 1586)

A N-VALUE (BLOWS PER FOOT)

33 OCD —

.. 0

#2

LU

h

• o 9 in 0 LU Z on LU O

LU D-

<U- 10 x o O —

O

24 IL — () Q LU e

( ill

U

—Z.

0Qu 10.

DEL

>nQ

860 12/5/24Completion Date:Surface Elevation □ - PP/2O - QU/2A - UU/2

250,5 1,5 2.0Datum NAVD88 STANDARD PENETRATION RESISTANCE§5°00 — Il tESu Zmm

DDESCRIPTION OF MATERIAL I- LU

> Q_ O

PLH ILL0Oo Z o O 30 40 5010 20 J.

CLAY - brown, stiff to very stiff, Sean, some sand - (CL)

A3-4-6 SS1

A5-9-11 SS2

5—

SAND - brown, medium dense, fine - SP ASS37-9-9

• A2 SS48-9-10

i G ®6 10— n s

SAND - brown, medium dense, fine - SPImFO y

0.= ' ASS53-5-8Q.

FO - 15

UJ

Z2oQ

- 20- 0... o “2o Z

Check by: MHM App'vd by: JAW DRILLING DATAGROUNDWATER DATA Date: 1-21-25Date: 1/16/25

__ HOLLOW STEM4" AUGER (O UESWASHBORING FROM___FEETENCOUNTERED AT 13.5 FEET Y TM

RAW LOGGERDJT DRILLER

QME 55TRK DRILL RIG

HAMMER TYPE Auto

REMARKS:

LOG OF BORING: B-3

Project No. J045885.01

Drawn by: RAW Date: 12/6/24

O

Combined Sewer Overflow Separation

Atchison, Kansas

O i Q. < a weathered shale Boring terminated at 15 feet.

CLAY - dark gray and brown, very stiff, lean, some sand and gravel - CL

8 o 0C En n D

LU

LU

LL

LU •

Q 0)

Q.

LU

1 n

LU

< 0 O Z

(ASTM D 1586)

A N-VALUE (BLOWS PER FOOT)

WATER CONTENT, %

_ ASPHALT-1.5 inches________________ CONCRETE - 5 inches (poor recovery)

LD

£3 =O

2 0) 0) UJ

20 uj O

LU C

30 xo O-

O z<

UJ D

CD C

LU <

QO

IL o"

10E5 $84

E2 Sui

— 5 0 l-

O-

CD —

BORING LOG: TERMS AND SYMBOLS

Plasticity Chart

•r 0ve d

| CH

H

* CL

0% 10% 20% 30% 40 % 50 % 60% 70% Liquid Limit

3/4 10tl 40 20012 3 4

GRAVEL SANDBOULDERS COBBLES SILT CLAY

76.2300 4.76 0.42 0.074 0.005

SOIL GRAIN SIZE IN MILLIMETERS

UNIFIED SOIL CLASS

Major Divisions d

E2 Highly Organic Soils

STRENGTH OF COHESIVE SOILS DENSITY OF GRANULAR SOILS

Consistency Descriptive Term

RELATIVE COMPOSITION

O UES™

Sand and Sandy Soils

Silts and Clays

Silts and Clays

Liquid Limit Less Than 50

80%

70%

60%

50%

40%

30%

20%

10%

0%

Gravel and

Gravelly Soil

Approximate N 60 -Value Range

Q c Liquid Limit

Greater Than 50

Oto 10% 10 to 20% 20 to 35% 35 to 50%

Relative composition and Unified Soil Classification System (USCS) designations are based on visual descriptions and are approximate only. If laboratory tests were performed to classify the soil, the USCS designation is shown in parenthesis.

N-Value (Blow Count) is the…