Loading...
HomeMy WebLinkAbout007 - Stormwater Design ReportSTORMWATER DRAINAGE REPORT FOR Alder Ridge & Sage Peak Apartments Bozeman, MT 59715 August 2025 Parcel No.: TBD Planning Application No.: 24122 Owner Name: GRAF ST APARTMENTS, LLC. Applicant Address: PO Box 4108 Bellevue, WA 98009 Applicant Telephone: (425) 736-0580 Project Engineer Name: Taylor Bellefeuille P.E. Project Engineer Address: 1201 3rd Ave, Suite 2800 Seattle, WA 98101 Project Engineer Telephone: (206) 800 - 1889 Project Engineer Email: taylor.bellefeuille@kimley-horn.com Contact Name: Melanie Davies Contact Address: 10900 NE 8th St Ste. 1200, Bellevue, WA 98004 Project Contact: (425) 293-4412 Contact Email: melanie.davies@devcous.com Alder Ridge and Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Preliminary Drainage Report August 2025 Page ii PREPARED FOR: GRAF ST APARTMENTS, LLC. PO BOX 4108 BELLEVUE, WA 98009 PREPARED BY: KIMLEY-HORN AND ASSOCIATES, INC. 1201 3rd Ave, Suite 2800 SEATTLE, WA 98101 Taylor Bellefeuille, PE Disclosure Statement: This document, together with the concepts and designs presented herein, as an instrument of service, is intended only for the specific purpose and client for which it was prepared. Reuse of and improper reliance on this document without written authorization and adaptation by Kimley-Horn and Associates, Inc. shall be without liability to Kimley-Horn and Associates, Inc. Alder Ridge and Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Preliminary Drainage Report August 2025 Page iii Table of Contents 1.0 INTRODUCTION ...............................................................................................................................1 2.0 HYDROLOGY AND HYDROGEOLOGY .....................................................................................................2 3.0 EXISTING SITE CONDITIONS................................................................................................................2 4.0 PROPOSED SITE DESIGN ....................................................................................................................3 5.0 EVALUATION OF MAJOR STORM FLOOD RISKS.......................................................................................4 6.0 STORMWATER FACILITIES MAINTENANCE PLAN.....................................................................................4 ATTACHMENTS AND APPENDICES APPENDIX A: MAPS ATTACHMENT NO. 1 – VICINITY MAP ATTACHMENT NO. 2 – PRE-DEVELOPMENT DRAINAGE AREA MAP ATTACHMENT NO. 3 – POST-DEVELOPMENT DRAINAGE AREA MAP ATTACHMENT NO. 4 – FEMA FLOOD INSURANCE RATE MAP (FIRM) APPENDIX B: GEOTECHNICAL REPORT (BY OTHERS) APPENDIX C: DETENTION SYSTEM SIZING CALCULATIONS APPENDIX D: CONVEYANCE AND WATER QUALITY CALCULATIONS Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 1 1.0 INTRODUCTION The Graf St Multifamily project proposes to develop two lots that combine for a total of 9.19-acres into an affordable multi-family apartment housing complex. Lot 1 makes up most of the site area and is a total of 7.45 acres. Lot 2 covers the remainder of the site area in the northwest corner of the parcel, consisting of 1.74 acres Both lots are currently vacant, mostly grass covered, and zoned R-1, but as part of plat application SRX-II Subdivision 24112, the proposed zoning for the subject parcel will be REMU. The project site is located north of Graf St, east of the proposed S 17th Ave, west of the proposed S 15th Ave and south of the proposed Staudaher St in Bozeman, MT within Gallatin County. The project area is bounded by undeveloped parcels in all directions, Graf St lies to the south of the parcel boundary. Approximately all 9.19 acres of the site (both lots) will be disturbed for regrading, drainage, and development purposes. The existing site is grass covered and gradually slopes north at under 5%. The site is not located near any environmentally critical areas or buffer zones. The site is designated as flood hazard zone X (area of minimal flood hazard) and is not located within a FEMA Special Flood Hazard Area (SFHA). The site has known high groundwater and wetlands exist on the property to the north. The extent of these wetlands will be determined as part of the SRX II Subdivision. The purpose of this technical information report is to provide an explanation of the site improvements and to demonstrate how the project will meet stormwater requirements. Figure 1 below shows the project site location. Figure 1. Vicinity Map PROJECT SITE Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 2 2.0 HYDROLOGY AND HYDROGEOLOGY The design storm was modeled from the COB Design and Construction Standards Table 6.5.1 24-hour storm event. This table has been provided below for reference. The geotechnical report has been provided in Appendix B. 3.0 EXISTING SITE CONDITIONS The existing site is undeveloped with the majority of landcover as grass. Generally, the site sheet flows north onto neighboring property in existing conditions. There are no existing stormwater facilities onsite. The site sheet flows to the north, with no defined point discharge outfall. The site conditions encountered on the site generally consisted of a layer of vegetated topsoil which was underlain by a layer of sandy lean clay to depths ranging from 2.5-5 feet BGS. Beneath the sandy lean clay, gravel with sand and cobbles were detected. In general, the soils are predominantly classified as Turner Loam with a hydrologic soil group of type C. Based on existing on-site monitoring wells and a study conducted by Providence, the seasonal high groundwater was found to be as high as 0.36 feet of the ground surface. The existing conditions are shown in Appendix A, Attachment 2. The study conducted by Providence and the geotechnical report have been provided in B. No offsite contributing areas flow onto this site. Existing Conditions – Summary Table Area Classification Basin 1 9.19 AC C Grassland HydroCAD was used to model the existing basin. The existing HydroCAD model can be found in Appendix C. The project site is not located within a FEMA Special Flood Hazard Area (SFHA). The site is mapped on FEMA Flood Insurance Rate Map (FIRM) Panels 30031C0808E and 30031C0816E, effective date 4/21/2021 for both panels. The Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 3 site lies within an unshaded FEMA Zone X, outside the 0.2% annual chance floodplain. See the FIRM Panel in Appendix A, Attachment 5. 4.0 PROPOSED SITE DESIGN The property is included in the SRX II preliminary plat subdivision and will be subdivided into two parcels with the northwest parcel to contain a senior apartment building. The proposed site improvements will include apartment buildings, a clubhouse, parking, and associated utility and storm infrastructure. The stormwater system was designed to the COB Design and Construction Standards, Chapter 6. In the final design, stormwater runoff from the development will route into inlets throughout the site where water will then be conveyed to a detention system below grade. Both lots will be incorporated into this stormwater system for a total area of 9.19 acres of area coverage. The proposed conditions are shown in Appendix A, Attachment 3. A summary table of the proposed conditions is shown below. Proposed Conditions – Summary Table Area Classification Basin 1 2.40 AC C Lawn Basin 1 6.79 AC Roof, Sidewalk, Pavement The detention storage has been sized to control the rate of runoff to pre-developed levels for the full range of storm events (2-year through 100-year). Calculations showing the proposed detention volume and runoff can be seen in Appendix C. Infiltration has not been factored into the sizing of the vault due to extremely shallow groundwater encountered on-site. As such, the detention system will be impermeable. Tables of the pre and post runoff rates from the model in Appendix C are shown below for reference. Existing Runoff Proposed Runoff Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 4 Per section 6.9.1 of the COB Design and Construction standards, a Contech CDS water quality facility that removes over 80% total suspended solids has been designed to treat the first 0.5 inches of rainfall. The calculations for this unit can be found in Appendix D. The detention system will outfall through a 15” diameter pipe to a proposed public stormwater system located in South 15th Ave. Conveyance calculations for the storm infrastructure onsite were completed using the Bentley StormCAD program. The rational method was used with a 10-year and 100-year storm event per City of Bozeman standards. The rainfall for these events was taken from table 6.5.1, shown above for reference. Results for the conveyance calculations can be seen in Appendix D. 5.0 EVALUATION OF MAJOR STORM FLOOD RISKS The rational method and StormCAD was used to model the Major Storm (100-year) event. Results for the conveyance calculations can be seen in Appendix D. In the Major Storm event, the maximum elevation of stormwater in the system is 4971.43. This is ~3.3 below the lowest proposed building finish floor onsite. The Major Storm event will result in no above finish grade ponding. Overland release for the site is in the NE corner. 6.0 STORMWATER FACILITIES MAINTENANCE PLAN A stormwater facilities maintenance and access agreement are planned to be recorded between both lots on this parcel. The multifamily (larger) lot will own the stormwater infrastructure and grant access across the lot line to allow inspection, repair, and maintenance between the lots for the stormwater infrastructure. An Operations and Maintenance manual has been provided below that specifies the frequency and methods of inspection and cleaning of the stormwater infrastructure. kimley-horn.com 1201 Third Avenue, Suite 2800, Seattle, WA 98101 206.800.1889 MEMORANDUM To:City of Bozeman – Engineering Department From:Taylor Bellefeuille, PE Kimley-Horn and Associates, Inc. Date:04/01/2025 Stormwater Maintenance Objective The stormwater management system for the proposed development is intended to collect and convey the stormwater runoff. Regular maintenance procedures are required to ensure the consistent operation and safe conditions of the stormwater management facilities and prevent the occurrence of problems and malfunctions. The maintenance program provides the stormwater maintenance procedures for the site. The maintenance plan shall be evaluated and adjusted as needed. All the elements on site are to be privately funded and maintained. Regularly scheduled inspection and maintenance is necessary to ensure long-term operation and safety of stormwater management facilities. Inspection and maintenance procedure shall berecorded through detailed logs. Copies of maintenance related work orders shall be retained. Logs, work orders, the maintenance plan, and documentation of its evaluation shall be made available, upon request by any public entity with administrative, health, environmental or safety authority of the site. Constructed Stormwater Facility Elements Primary elements of the stormwater facilities include catch basins, storm drain manholes, a proprietary water quality unit and a proprietary below grade storage system. Inspection and Maintenance Procedures The conveyance systems, including inlets, manholes, and pipes, along with the proposed underground detention facilities, are expected to receive and/or accumulate debris and sediment. These systems shall be inspected for clogging and sediment accumulation at least annually and shall be inspected for trash and debris removal at least bi-annually and may require cleaning to prevent the loss of discharge capacity storage volume. Refer to the manufacturer’s recommendations for inspection schedules for the underground detention. Sediment removal should take place when all runoff has drained from the pipe networks and the systems are reasonably dry. Disposal of debris, trash, sediment, and other waste material should be done atsuitable disposal/recycling sites and in compliance with all applicable local, state, and federal waste regulations. All structural components must be inspected for cracking, subsidence, breaching, wearing and deterioration at least annually. The conditions of surrounding and above lying materials shall be inspected for evidence of potential failures or deterioration. Structural components shall be inspected at least twice annually and whenever the systems are cleaned. The underground detention systems shall be inspected, maintained, and replaced as necessary in accordance with the manufacturer’s recommendations and maintenance schedule shown below Two people may be needed to perform routine maintenance of the conveyance systems. The routine equipment expected to be utilized for the maintenance tasks may include a jet vacuum vehicle, shovels, lighting equipment and a wheelbarrow or truck for the hauling off of debris. All inspections and maintenance operations shall be documented and logged. All documentations and logs shall be retained for future review. D D D D D D D D W W W W W W W W W WW W W W WWWWWWWWWWWWWWWW W W SSSSSSSSSSSSUGEUGE UGE UGEUG E UGEUGE UGEU G E UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE D D T T TE EE WATERWATER WATER WATER WATER WATER WATER WATERMECHWATER / RISER ROOM BUILDING 1 FFE = 4976.27 BUILDING 3 FFE = 4974.77 BUILDING 7 FFE = 4980.40 BUILDING 8 FFE = 4981.00 BUILDING 4FFE = 4975.67BUILDING 5FFE = 4978.57BUILDING 6FFE =4979.97BUILDING 10FFE = 4978.25BUILDING 9FFE = 4980.37BUILDING 2 CLUBHOUSE FFE = 4977.84 STAUDAHER ST SOUTH 15TH AVEWEST GRAF STREETSOUTH 17TH AVE10.0' BUILDING SETBACK 10.0' BUILDING SETBACK 10.0' BUILDING SETBACK 10.0' BUILDING SETBACK C3.00 NORTH OVERALLGRADING ANDDRAINAGE PLAN©ALDER RIDGE & SAGE PEAKAPARTMENTSPREPARED FORGRAF STREETAPARTMENTS, LLC.® BEFORE YOU DIG, CALL 1-800-424-5555 GRADING & DRAINAGE NOTES 1.ADA ACCESSIBLE SPACES ARE DESIGNED TO HAVE A MAXIMUM SLOPE OF 2.0% IN ANY DIRECTION. 2.THE PROPOSED ACCESSIBLE PATH SIDEWALKS AROUND THE BUILDING AND ALONG THE PROPERTY FRONTAGES SHALL HAVE A MAXIMUM 2% CROSS SLOPE AND 5% LONGITUDINAL SLOPE. 3.CONTRACTOR TO VERIFY DEPTH OF EXISTING UNDERGROUND UTILITIES PRIOR TO PLACEMENT OF ANY PAVEMENT AND NOTIFY KIMLEY-HORN IF ANY CONFLICTS EXIST. 4.TOP OF CURB SHALL BE 6" ABOVE PAVEMENT ELEVATION UNLESS OTHERWISE SPECIFIED. 5.SQUARE STORM DRAIN INLETS TO BE CONSTRUCTED PER CITY STANDARD DETAIL 02720-1A 6.STORM DRAIN MANHOLES WITHIN GUTTER LINES TO BE CONSTRUCTED PER CITY STANDARD PLAN 02720-1B 7.STANDARD RISER INLETS TO BE CONSTRUCTED PER CITY STANDARD PLAN 02720-2 8.STORM DRAIN MANHOLES NOT WITHIN GUTTER LINES TO BE CONSTRUCTED PER CITY STANDARD PLAN 02720-3. PROPERTY LINE SETBACK LINE PROPOSED EASEMENT PROPOSED LOT LINE EXISTING CONTOUR PROPOSED MAJOR CONTOUR PROPOSED MINOR CONTOUR GRADE BREAK SWALE PROPOSED SLOPE EXISTING SLOPE PROPOSED SPOT ELEVATION PROPOSED STORM DRAIN SEWER MANHOLE SEWER CLEANOUT STORM MANHOLE STORM DRAIN INLET YARD DRAIN GRADING LEGEND SPOT ELEVATION LEGEND RIM RIM ELEVATION P PAVEMENT D BUILDING DOOR BC BOTTOM OF CURB HP HIGH POINT FFE FINISHED FLOOR ELEVATION SWALE GRASS SWALE CENTERLINE TC TOP OF CURB EX EXISTING SW SIDEWALK ME MATCH EXISTING LP LOW POINT INV INVERT OF PIPE DuroMaxx® SRPE Detention & Infiltration Maintenance Guide ENGINEERED SOLUTIONS STEEL REINFORCED PE TECHNOLOGY 2 3 DuroMaxx® Steel Reinforced Polyethylene (SRPE) Detention and Infiltration Systems Maintenance Underground storm water detention and infiltration systems should be inspected at regular intervals and maintained when necessary to ensure optimum performance. The rate at which the system collects pollutants will depend more heavily on site activities than the size or configuration of the system. Inspection Inspection is the key to effective maintenance and is easily performed. Contech Engineered Solutions recommends ongoing quarterly inspections of the accumulated sediment. Sediment deposition and transport may vary from year to year and quarterly inspections will help insure that systems are cleaned out at the appropriate time. Inspections should be performed more often in the winter months in climates where sanding operations may lead to rapid accumulations, or in equipment washdown areas. It is very useful to keep a record of each inspection. A sample inspection log is included for your use. Systems should be cleaned when inspection reveals that accumulated sediment or trash is clogging the discharge orifice. Contech suggests that all systems be designed with an access/inspection manhole situated at or near the inlet and the outlet orifice. Should it be necessary to get inside the system to perform maintenance activities, all appropriate precautions regarding confined space entry and OSHA regulations should be followed. Cleaning Maintaining an underground detention or retention system is easiest when there is no flow entering the system. For this reason, it is a good idea to schedule the cleanout during dry weather. Accumulated sediment and trash can typically be evacuated through the manhole over the outlet orifice. If maintenance is not performed as recommended, sediment and trash may accumulate in front of the outlet orifice. Manhole covers should be securely seated following cleaning activities. 2 3 Inspection & Maintenance Log Sample Template __________” Diameter System Location: Anywhere, USA Date Depth of Sediment Accumulated Trash Maintenance Performed Maintenance Personnel Comments 12/01/14 2”None Removed Sediment B. Johnson Installed 03/01/15 1”Some Removed Sediment and Trash B. Johnson Swept parking lot 06/01/15 0”None None 09/01/15 0”Heavy Removed Trash S. Riley 12/01/15 1”None Removed Sediment S. Riley 04/01/15 0”None None S. Riley 04/15/15 2 Some Removed Sediment and Trash ACE Environmental Services SAMPL E Support Drawings and specifications are available at www.ContechES.com. Site-specific support is available from our engineers. ©2016 Contech Engineered Solutions LLC Contech Engineered Solutions LLC provides site solutions for the civil engineering industry. Contech’s portfolio includes bridges, drainage, sanitary sewer, earth stabilitation and stormwater treatment products. For information, visit www.ContechES.com or call 800.338.1122. NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS AN EXPRESSED WARRANTY OR AN IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. SEE THE CONTECH STANDARD CONDITION OF SALES (VIEWABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION. The product(s) described may be protected by one or more of the following US patents: 5,322,629; 5,624,576; 5,707,527; 5,759,415; 5,788,848; 5,985,157; 6,027,639; 6,350,374; 6,406,218; 6,641,720; 6,511,595; 6,649,048; 6,991,114; 6,998,038; 7,186,058; 7,296,692; 7,297,266; related foreign patents or other patents pending. 800.338.1122 www.ContechES.com ENGINEERED SOLUTIONS STEEL REINFORCED PE TECHNOLOGY CDS® Inspection and Maintenance Guide ENGINEERED SOLUTIONS Maintenance The CDS system should be inspected at regular intervals and maintained when necessary to ensure optimum performance. The rate at which the system collects pollutants will depend more heavily on site activities than the size of the unit. For example, unstable soils or heavy winter sanding will cause the grit chamber to fill more quickly but regular sweeping of paved surfaces will slow accumulation. Inspection Inspection is the key to effective maintenance and is easily performed. Pollutant transport and deposition may vary from year to year and regular inspections will help ensure that the system is cleaned out at the appropriate time. At a minimum, inspections should be performed twice per year (e.g. spring and fall) however more frequent inspections may be necessary in climates where winter sanding operations may lead to rapid accumulations, or in equipment washdown areas. Installations should also be inspected more frequently where excessive amounts of trash are expected. The visual inspection should ascertain that the system components are in working order and that there are no blockages or obstructions in the inlet and separation screen. The inspection should also quantify the accumulation of hydrocarbons, trash, and sediment in the system. Measuring pollutant accumulation can be done with a calibrated dipstick, tape measure or other measuring instrument. If absorbent material is used for enhanced removal of hydrocarbons, the level of discoloration of the sorbent material should also be identified during inspection. It is useful and often required as part of an operating permit to keep a record of each inspection. A simple form for doing so is provided. Access to the CDS unit is typically achieved through two manhole access covers. One opening allows for inspection and cleanout of the separation chamber (cylinder and screen) and isolated sump. The other allows for inspection and cleanout of sediment captured and retained outside the screen. For deep units, a single manhole access point would allows both sump cleanout and access outside the screen. The CDS system should be cleaned when the level of sediment has reached 75% of capacity in the isolated sump or when an appreciable level of hydrocarbons and trash has accumulated. If absorbent material is used, it should be replaced when significant discoloration has occurred. Performance will not be impacted until 100% of the sump capacity is exceeded however it is recommended that the system be cleaned prior to that for easier removal of sediment. The level of sediment is easily determined by measuring from finished grade down to the top of the sediment pile. To avoid underestimating the level of sediment in the chamber, the measuring device must be lowered to the top of the sediment pile carefully. Particles at the top of the pile typically offer less resistance to the end of the rod than consolidated particles toward the bottom of the pile. Once this measurement is recorded, it should be compared to the as-built drawing for the unit to determine weather the height of the sediment pile off the bottom of the sump floor exceeds 75% of the total height of isolated sump. Cleaning Cleaning of a CDS systems should be done during dry weather conditions when no flow is entering the system. The use of a vacuum truck is generally the most effective and convenient method of removing pollutants from the system. Simply remove the manhole covers and insert the vacuum hose into the sump. The system should be completely drained down and the sump fully evacuated of sediment. The area outside the screen should also be cleaned out if pollutant build-up exists in this area. In installations where the risk of petroleum spills is small, liquid contaminants may not accumulate as quickly as sediment. However, the system should be cleaned out immediately in the event of an oil or gasoline spill should be cleaned out immediately. Motor oil and other hydrocarbons that accumulate on a more routine basis should be removed when an appreciable layer has been captured. To remove these pollutants, it may be preferable to use absorbent pads since they are usually less expensive to dispose than the oil/water emulsion that may be created by vacuuming the oily layer. Trash and debris can be netted out to separate it from the other pollutants. The screen should be power washed to ensure it is free of trash and debris. Manhole covers should be securely seated following cleaning activities to prevent leakage of runoff into the system from above and also to ensure that proper safety precautions have been followed. Confined space entry procedures need to be followed if physical access is required. Disposal of all material removed from the CDS system should be done in accordance with local regulations. In many jurisdictions, disposal of the sediments may be handled in the same manner as the disposal of sediments removed from catch basins or deep sump manholes. Table 1: CDS Maintenance Indicators and Sediment Storage Capacities 800.925.5240www.ContechES.com Support• Drawings and specifications are available at www.contechstormwater.com. • Site-specific design support is available from our engineers. ©2017 Contech Engineered Solutions LLC, a QUIKRETE Company Contech Engineered Solutions LLC provides site solutions for the civil engineering industry. Contech’s portfolio includes bridges, drainage, sanitary sewer, stormwater, earth stabilization and wastewater treament products. For information, visit www.ContechES.com or call 800.338.1122 NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS AN EXPRESSED WARRANTY OR AN IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. SEE THE CONTECH STANDARD CONDITION OF SALES (VIEWABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION. The product(s) described may be protected by one or more of the following US patents: 5,322,629; 5,624,576; 5,707,527; 5,759,415; 5,788,848; 5,985,157; 6,027,639; 6,350,374; 6,406,218; 6,641,720; 6,511,595; 6,649,048; 6,991,114; 6,998,038; 7,186,058; 7,296,692; 7,297,266; 7,517,450 related foreign patents or other patents pending. ENGINEERED SOLUTIONS CDS Model Diameter Distance from Water Surface to Top of Sediment Pile Sediment Storage Capacity ft m ft m y3 m3 CDS1515 3 0.9 3.0 0.9 0.5 0.4 CDS2015 4 1.2 3.0 0.9 0.9 0.7 CDS2015 5 1.3 3.0 0.9 1.3 1.0 CDS2020 5 1.3 3.5 1.1 1.3 1.0 CDS2025 5 1.3 4.0 1.2 1.3 1.0 CDS3020 6 1.8 4.0 1.2 2.1 1.6 CDS3025 6 1.8 4.0 1.2 2.1 1.6 CDS3030 6 1.8 4.6 1.4 2.1 1.6 CDS3035 6 1.8 5.0 1.5 2.1 1.6 CDS4030 8 2.4 4.6 1.4 5.6 4.3 CDS4040 8 2.4 5.7 1.7 5.6 4.3 CDS4045 8 2.4 6.2 1.9 5.6 4.3 CDS5640 10 3.0 6.3 1.9 8.7 6.7 CDS5653 10 3.0 7.7 2.3 8.7 6.7 CDS5668 10 3.0 9.3 2.8 8.7 6.7 CDS5678 10 3.0 10.3 3.1 8.7 6.7 CDS Inspection & Maintenance Log CDS Model: Location: Water Floatable Describe Maintenance Date depth to Layer Maintenance Personnel Comments sediment1 Thickness2 Performed —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— 1. The water depth to sediment is determined by taking two measurements with a stadia rod: one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than the values listed in table 1 the system should be cleaned out. Note: to avoid underestimating the volume of sediment in the chamber, the measuring device must be carefully lowered to the top of the sediment pile. 2. For optimum performance, the system should be cleaned out when the floating hydrocarbon layer accumulates to an appreciable thickness. In the event of an oil spill, the system should be cleaned immediately.CDS Maintenance Guide - 7/18 (PDF) Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 5 APPENDIX A: MAPS ©2023 KIMLEY-HORN AND ASSOCIATES, INC 1201 3RD AVE, SUITE 2800, SEATTLE, WA 98101 PHONE: 206 607 2600 WWW.KIMLEY-HORN.COM NORTH ©2025 KIMLEY-HORN AND ASSOCIATES, INC 1201 3RD AVE, SUITE 2800, SEATTLE, WA 98101 PHONE: 206 607 2600 WWW.KIMLEY-HORN.COM NORTH D D D D D D D D D HH HH HHHH HH HH TOP NUT EL=4975.33 W W W W W WWWWWW SSSDSD SDSDSD SDUGEUGEUGEUGEUGE UGE UGE UGE UGE TOP NUT EL=4974.11 TOP NUT EL=4973.16 S S S D D T T TE IEE 2' STORM PIPE WITH FLARED END SECTION INV=4976.73 CURB INLETRIM EL=4979.98 18" INV N=4975.98 18" INV NE=4976.08 18" INV S=4976.08 STORM MH RIM EL=4980.56 18" INV N=4976.36 18" INV NE=4976.36 18" INV S=4976.36 STORM PIPE WITH FLARED END SECTION 42" INV=4972.91 STORM MH RIM EL=4980.76 42" INV N=4973.31 42" INV S=4973.5115" INV E=4974.91 15" INV W=? CURB INLET RIM EL=4980.42 15" INV W=4976.47 CURB INLET RIM EL=4980.39 15" INV E=4976.49 CURB INLET RIM EL=4979.96 24" INV S=?C-W 1/16 COR. SEC 24, FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" SANITARY MH RIM EL=4980.71 FULL OF WATER 2' STORM PIPE WITH FLARED END SECTION INV=4977.69 ELECTRIC STUBFIBER STUB TELECOM BOX FIBER STUB 1.5" VERTICAL PIPE FIBER STUB TELECOM BOX TOP NUT EL=4975.33 W W W W W WWWWWW SSSDSD SDSDSD SDUGEUGEUGEUGEUGE UGE UGE UGE UGE TOP NUT EL=4974.11 TOP NUT EL=4973.16 S S S D D T T TE IEE 2' STORM PIPE WITH FLARED END SECTION INV=4976.73 CURB INLETRIM EL=4979.98 18" INV N=4975.98 18" INV NE=4976.08 18" INV S=4976.08 STORM MH RIM EL=4980.56 18" INV N=4976.36 18" INV NE=4976.36 18" INV S=4976.36 STORM PIPE WITH FLARED END SECTION 42" INV=4972.91 STORM MH RIM EL=4980.76 42" INV N=4973.31 42" INV S=4973.5115" INV E=4974.91 15" INV W=? CURB INLET RIM EL=4980.42 15" INV W=4976.47 CURB INLET RIM EL=4980.39 15" INV E=4976.49 CURB INLET RIM EL=4979.96 24" INV S=?C-W 1/16 COR. SEC 24, FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" FOUND 1-1/2" ORANGE PLASTIC CAP, STAMPED "MERIDIAN 18342" SANITARY MH RIM EL=4980.71 FULL OF WATER 2' STORM PIPE WITH FLARED END SECTION INV=4977.69 ELECTRIC STUBFIBER STUB TELECOM BOX FIBER STUB 1.5" VERTICAL PIPE FIBER STUB TELECOM BOX WATER WATER WATER WATER WATER WATER WATER WATERMECHWATER / RISERROOM ©2025 KIMLEY-HORN AND ASSOCIATES, INC 1201 3RD AVE, SUITE 2800, SEATTLE, WA 98101 PHONE: 206 607 2600 WWW.KIMLEY-HORN.COM NORTH 2.40 AC 6.79 AC Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 6 APPENDIX B: GEOTECH REPORT = Data Input Cell Measuring Depth GW Depth Measuring Depth GW Depth Measuring Depth GW Depth Measuring Depth GW Depth Measuring Depth GW Depth Measuring Depth GW Depth Measuring Depth GW Depth Measuring Depth GW Depth Measuring Depth GW DepthMeasuring DepthGW Depth 5 4981.350 4983.720 4.97 -2.60 5.03 -2.66 5.01 -2.64 5.59 -3.22 6.60 -4.23 6.65 -4.28 6.72 -4.35 7.32 -4.95 7.27 -4.9 6.84 -4.47 6 4988.690 4991.390 5.71 -3.01 5.84 -3.14 5.82 -3.12 5.40 -2.7 5.02 -2.32 5.70 -3 6.03 -3.33 6.89 -4.19 6.91 -4.21 6.32 -3.62 7 4987.860 4989.980 5.07 -2.95 5.21 -3.09 4.82 -2.7 4.90 -2.78 4.20 -2.08 5.00 -2.88 5.60 -3.48 6.12 -4 6.34 -4.22 5.45 -3.33 8 4980.500 4982.060 4.21 -2.65 4.31 -2.75 4.26 -2.7 4.57 -3.01 4.78 -3.22 5.40 -3.84 5.87 -4.31 6.30 -4.74 6.54 -4.98 5.78 -4.22 New 9 4974.717 4979.013 6.84 -2.54 6.90 -2.60 6.45 -2.154 5.95 -1.654 6.10 -1.804 6.80 -2.504 6.69 -2.394 7.52 -3.224 7.37 -3.074 6.78 -2.484 10 4969.270 4972.179 4.85 -1.94 4.87 -1.96 4.87 -1.961 4.60 -1.691 4.73 -1.821 4.45 -1.541 5.20 -2.291 5.79 -2.881 5.51 -2.601 5.28 -2.371 11 4969.810 4971.928 Empty #N/A empty #N/A Empty #N/A Empty #N/A Empty #N/A Empty #N/A Empty #N/A Empty #N/A Empty #N/A Empty #N/A 12 4962.290 4965.623 4.42 -1.09 4.39 -1.06 4.40 -1.067 4.42 -1.087 4.45 -1.117 4.60 -1.267 4.57 -1.237 4.78 -1.447 4.49 -1.157 4.44 -1.107 13 4961.347 4963.156 3.92 -2.11 4.28 -2.47 3.92 -2.111 3.50 -1.691 3.52 -1.711 4.20 -2.391 6.09 -4.281 6.32 -4.511 6.45 -4.641 6.41 -4.601 14 4969.707 4972.136 4.10 -1.67 4.10 -1.67 4.09 -1.661 4.59 -2.161 5.66 -3.231 4.75 -2.321 6.00 -3.571 6.12 -3.691 6.20 -3.771 4.70 -2.271 15 4971.074 4974.457 5.51 -2.13 5.78 -2.40 5.74 -2.357 5.41 -2.027 5.45 -2.067 5.75 -2.367 6.40 -3.017 6.64 -3.257 6.63 -3.247 6.28 -2.897 16 4976.443 4978.868 4.97 -2.55 5.32 -2.89 4.97 -2.545 4.82 -2.395 4.11 -1.685 4.90 -2.475 5.30 -2.875 5.71 -3.285 5.77 -3.345 5.06 -2.635 New 17 4971.993 4976.132 5.88 -1.74 5.07 -0.93 4.90 -0.761 4.78 -0.641 4.50 -0.361 6.20 -2.061 6.65 -2.511 6.82 -2.681 6.72 -2.581 6.28 -2.141 Date Well #5 Well #6 Well #7 Well #8 Well #9 Well #10 Well #11 Well #12 Well #13 Well #14 Well #15 Well #16 Well #17 5/26/2023 -2.60 -3.01 -2.95 -2.65 -2.54 -1.94 #N/A -1.09 -2.11 -1.67 -2.13 -2.55 -1.74 6/2/2023 -2.66 -3.14 -3.09 -2.75 -2.60 -1.96 #N/A -1.06 -2.47 -1.67 -2.40 -2.89 -0.93 6/9/2023 -2.64 -3.12 -2.70 -2.70 -2.15 -1.96 #N/A -1.07 -2.11 -1.66 -2.36 -2.55 -0.76 6/16/2023 -3.22 -2.70 -2.78 -3.01 -1.65 -1.69 #N/A -1.09 -1.69 -2.16 -2.03 -2.39 -0.64 6/23/2023 -4.23 -2.32 -2.08 -3.22 -1.80 -1.82 #N/A -1.12 -1.71 -3.23 -2.07 -1.68 -0.36 7/7/2023 -4.28 -3.00 -2.88 -3.84 -2.50 -1.54 #N/A -1.27 -2.39 -2.32 -2.37 -2.47 -2.06 7/19/2023 -4.35 -3.33 -3.48 -4.31 -2.39 -2.29 #N/A -1.24 -4.28 -3.57 -3.02 -2.88 -2.51 7/28/2023 -4.95 -4.19 -4.00 -4.74 -3.22 -2.88 #N/A -1.45 -4.51 -3.69 -3.26 -3.28 -2.68 8/11/2023 -4.90 -4.21 -4.22 -4.98 -3.07 -2.60 #N/A -1.16 -4.64 -3.77 -3.25 -3.35 -2.58 9/27/2023 -4.47 -3.62 -3.33 -4.22 -2.48 -2.37 #N/A -1.11 -4.60 -2.27 -2.90 -2.64 -2.14 9/27/20237/28/2023 8/11/2023Well / Date Ground Elevation Measuring Point Elevation 6/9/2023 6/16/2023 7/19/20236/23/2023 7/7/20235/26/2024 6/2/2023 -6.00 -5.00 -4.00 -3.00 -2.00 -1.00 0.00 5/14/2023 6/3/2023 6/23/2023 7/13/2023 8/2/2023 8/22/2023 9/11/2023 10/1/2023 10/21/2023 DEPTH TO GROUNDWATERMONITORING DATE 2023 Groundwater Monitoring Well #5 Well #6 Well #7 Well #8 Well #9 Well #10 Well #11 Well #12 Well #13 Well #14 Well #15 Well #16 Well #17 8S8S8S8S8S8S8S8SS S 8S 8S8S8S8SSSSSSSS8S8S8S8S8S8S8S8S8S8S8S8SS 8S S8S8S8S8W8W 8W8W8W8W8W 8W 8W 8W 10W10W10W10W10W10W10W10W10W10W10W10W10W10W10WDYH 8W B8W8W8W8W8W8W8W8W8W8W8W8W 8W 8W 8W 8WDYH 8S8S8S8S8S8S8S8SS S 8S 8S8S8S8SSSSSSSS8S8S8S8S8S8S8S8S8S8S8S8SS 8S S8S8S8S8W8W 8W8W8W8W8W 8W 8W 8W 10W10W10W10W10W10W10W10W10W10W10W10W10W10W10WDYH 8W B8W8W8W8W8W8W8W8W8W8W8W8W 8W 8W 8W 8WDYH 8S 8S 8S 8S 8S 8S 8S 8S 18S 18S 18S 18S 18S 18S 18S 18S 18S 18S 18S 18S 18S 18S 18S 18S 24W 24W 24W 24W 24W 24W 24W 24W 24W 24W 24W 24W 24W 24W 24W12W 18S 18S 18S 18S 10S 10S10S10S10S10S10S10S10S10S10S10S10S10S10S10S10S10S10S10S10SS8S8SSSS10W10WS8S8S8S8S8S8S8S8S8S8S8S8W8W8W8W8W8W8W8W8W8W8W8W8WSSS SSS8S 8S 8S 8S 8S 8S 8S 8S 8S 8S 8S 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W SSS LOT 17.52 acs.LOT 27.25 acs.N89°23'18"E 649.39'S0°42'18"E 65.05' R =120.00'L=99.60' Δ=47°33'14" S 4 6 ° 5 0 ' 5 6 "W 5 2 . 7 9 ' R=180.00'L=149.10' Δ=47°27'38" S0°36'42"E 268.13' N0°41'17"W 590.13' S0°36'42"E 559.55'S89°06'04"W19.24'S 4 1 ° 0 5 ' 3 7 " W 82 . 0 2 'S89°05'06"W 438.01'N0°41'17"W 623.18'N89°23'10"E 512.64'OPEN SPACE 12.40 acs.S0°42'18"E 64.95'R=180.00'L=125.10'Δ=39°49'15"N89°23'18"E 613.43'N0°09'06"W 180.30'S89°23'18"W 573.42'LOT 16.01 acs.S89°23'18"W 704.91'N0°36'42"W 235.31' R=120.00'L=99.40'Δ=47°27'38 "N4 6 ° 5 0 ' 5 6 " E 5 2 . 7 9 'R=180.00'L=24.29'Δ=7°43'59"S0°09'06"E 377.01'LOT 19.26 acs.S0°36'42"E 532.08'N89°06'04"E19.24'S40°46'21"E79.35'N89°05'06"E 360.91'R=255.00'L=116.43'Δ=26°09'38"R=345.00'L=162.19'Δ=26°56'07"N0°09'06"W 527.88'S89°23'18"W 704.43'MWMWMWMWMWMWMWMWMW©COPYRIGHT MORRISON-MAIERLE , INC. ,2023PLOTTED DATE: Dec/08/2023 PLOTTED BY: matt e.ekstromDRAWING NAME: N:\5659\018 Providence - ZMA Blk 1 MS 494\ACAD\Exhibits\5659.018 Groundwater Monitoring WellMap.dwg1/4 SEC.SECTIONTOWNSHIPRANGEPROJ. #:SHEET OFCOUNTY,DATE:SCALE:CLIENT:FIELD WORK:DRAWN BY:CHECKED BY:22 GALLATIN5659.0181"=70'12/2023JWNMMMI 5 EAST 2 SOUTH 24NWMONTANAPRINCIPAL MERIDIAN, MONTANAengineers surveyors pl anners scientis tsMorrisonMaierle2880 Techno logy B lvd WestBozeman, MT 59718Phone: 406.587.0721www.m-m.net7014035700SCALE IN FEETBASIS OF BEARINGBobcat Coordinate System, NAD83(2011) per the"Rocky Mountain Tr iba l Coordinate Re ferenceSystem" Handbook and User Guide, PublishedSeptember 30th, 2014 and subsequent revis ions ,established by observations with survey-gradeGNSS receivers.ALL LOTS ARE SUBJECT TO THE FOLLOWING UTILITYEASEMENTS (EXCEPT THE RESTRICTED LOTS):- 10' ALONG PUBLIC RIGHTS-OF-WAY- 10' ALONG SIDE LOT LINES- 10' ALONG REAR LOT LINESPUBLIC UTILITY EASEMENTS (P.U.E.)LEGENDSET A REBAR 5/8" DIA.., WITHAN ORANGE PLASTIC CAP, "MMI16411LS".FOUND REBAR AS MARKEDMID-SECTION CORNER2324FOUND BRASS CAPSECTION CORNERFOUND A.C. PER C.C.R.F. 4-48425242326FOUND A.C. ON 5/8 INCH REBARMARKED MERIDIAN LAND SURVEYING,INC.MEASURED DIMENSION(M)RECORDED DIMENSION PERMINOR SUBDIVISION No. 494(R)ALUMINUM CAPA.C.CERTIFIED CORNER RECORDATION FORMC.C.R.F.BLOCK 1BLOCK 1BLOCK 2BLOCK 3ARNOLD STREETSTAUDAHER STREETSOUTH 17TH AVENUE SOUTH 15TH AVENUE SOUTH 19TH AVENUE GRAF STREETPREVIOUS LOT 1 BLOCK 1MINOR SUB 494PREVIOUS LOT 4 BLOCK 1MINOR SUB 494PREVIOUS LOT 3 BLOCK 1MINOR SUB 494PREVIOUS LOT 2 BLOCK 1MINOR SUB 49410 FOOT PUBLIC WIDEUTILITY EASEMENT10 FOOT WIDE PUBLICSIDEWALK EASEMENT15 FOOT DITCHMAINTENANCE EASEMENT20 FOOT WIDEDITCH MAINTENANCEEASEMENTSTORM DRAINAGEEASEMENT20 FOOT WIDE DITCHMAINTENANCE EASEMENT10 FOOT WIDEPUBLIC UTILITYEASEMENTPREVIOUS LOT LINEPREVIOUS LOT LINE PREVIOUS LOT LINE PREVIOUS LOT LINEPR E V I O U S L O T L I N E PREVIOUS LOT LINEPREVIOUS LOT LINEPROPOSED WATERAND SEWER UTILITIESEXISTING WATERAND SEWER UTILITIESLOT 1 BLOCK 2MINOR SUB 494GROUNDWATERMON. WELL - #16GROUNDWATERMON. WELL - #17GROUNDWATERMON. WELL - #14SOUTH RANGE CROSSING - NORTH SUBDIVISIONGROUNDWATER MONITORING WELL LOCATIONGROUNDWATERMON. WELL - #10GROUNDWATERMON. WELL - #13GROUNDWATERMON. WELL - #12GROUNDWATERMON. WELL - #15GROUNDWATERMON. WELL - #9 Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials i Table of Contents Introduction .................................................................................................... 1 Project Description .......................................................................................... 1 Site Conditions ................................................................................................ 3 Geotechnical Characterization ......................................................................... 4 Seismic Site Class ............................................................................................ 5 Infiltration ...................................................................................................... 6 Corrosivity ...................................................................................................... 6 Geotechnical Overview .................................................................................... 7 Earthwork ....................................................................................................... 9 Site Preparation........................................................................................ 9 Excavation .............................................................................................. 10 Subgrade Preparation ............................................................................... 10 Soil Stabilization ...................................................................................... 11 Fill Material Types .................................................................................... 12 Fill Placement and Compaction Requirements ............................................... 14 Utility Trench Backfill ............................................................................... 15 Grading and Drainage ............................................................................... 16 Earthwork Construction Considerations ....................................................... 16 Construction Observation and Testing ......................................................... 17 Shallow Foundations ..................................................................................... 18 Design Parameters – Compressive Loads ..................................................... 18 Foundation Construction Considerations ...................................................... 19 Floor Slabs .................................................................................................... 20 Floor Slab Design Parameters .................................................................... 20 Floor Slab Construction Considerations ........................................................ 21 Below-Grade Structures................................................................................. 21 Lateral Earth Pressures ................................................................................. 22 Design Parameters ................................................................................... 22 Subsurface Drainage for Below-Grade Walls ................................................. 23 Pavements .................................................................................................... 24 General Pavement Comments .................................................................... 24 Pavement Design Parameters .................................................................... 25 Pavement Section Thicknesses ................................................................... 26 Pavement Drainage .................................................................................. 28 Pavement Maintenance ............................................................................. 29 Frost Considerations...................................................................................... 30 General Comments ........................................................................................ 31 Figures GeoModel Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials ii Attachments Exploration and Testing Procedures Photography Log Site Location and Exploration Plans Exploration and Laboratory Results Supporting Information Note: This report was originally delivered in a web-based format. Blue Bold text in the report indicates a referenced section heading. The PDF version also includes hyperlinks which direct the reader to that section and clicking on the logo will bring you back to this page. For more interactive features, please view your project online at client.terracon.com. Refer to each individual Attachment for a listing of contents. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 1 Introduction This report presents the results of our subsurface exploration and Geotechnical Engineering services performed for the proposed apartment complex to be located northeast of the intersection of South 19th Avenue and West Graf Street in Bozeman, Montana. The purpose of these services was to provide information and geotechnical engineering recommendations relative to: ■ Subsurface soil conditions ■ Groundwater conditions ■ Seismic site classification per IBC ■ Site preparation and earthwork ■ Dewatering considerations ■ Foundation design and construction ■ Floor slab design and construction ■ Lateral earth pressures ■ Pavement design and construction ■ Stormwater pond considerations (infiltration/percolation rates) ■ Frost considerations The geotechnical engineering Scope of Services for this project included the advancement of test borings, laboratory testing, engineering analysis, and preparation of this report. Drawings showing the site and boring locations are shown on the Site Location and Exploration Plan, respectively. The results of the laboratory testing performed on soil samples obtained from the site during our field exploration are included on the boring logs and as separate graphs in the Exploration Results section. Project Description Our initial understanding of the project was provided in our proposal and was discussed during project planning. A period of collaboration has transpired since the project was initiated, and our final understanding of the project conditions is as follows: Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 2 Item Description Information Provided An email request for proposal was provided by Ms. Melanie Davies of DevCo on November 28, 2023. The request included a Parcel Map. An updated site layout was provided prior to our second drill crew mobilization in July 2024. Project Description The conceptual plan includes multi-story buildings comprising several apartments for rent on the property. Associated parking lot, drive lanes, and landscaping are anticipated to be included within the development. Proposed Structures Structures associated with the project are anticipated to include 10 multi-story apartment buildings. The buildings are anticipated to consist of wood or light gauge metal framing with slab-on-grade (non-basement) construction. Finished Floor Elevations Planned finished floor elevations for each of the structures were provided in the site grading plan, as follows: Building 1: 4,977.47 feet MSL Building 2: 4,974.77 feet MSL Building 3: 4,973.27 feet MSL Building 4: 4,974.17 feet MSL Building 5: 4,977.07 feet MSL Building 6: 4,977.47 feet MSL Building 7: 4,978.67 feet MSL Building 8: 4,978.87 feet MSL Building 9: 4,978.87 feet MSL Building 10: 4,976.75 feet MSL Maximum Loads Anticipated structural loads were not provided. In the absence of information provided by the design team, we used the following loads in estimating settlement based on our experience with similar projects. ■ Columns: 125 kips ■ Walls: 4 kips per linear foot (klf) ■ Slabs: 150 pounds per square foot (psf) Grading/Slopes Proposed finished grade elevations for the building pads are expected to be at or near existing grade. Approximately 1 to 2 feet of cut/fill is anticipated to develop final grade, excluding remedial grading requirements. Below-Grade Structures We anticipate elevator pits will be included in the multi-story apartment buildings. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 3 Item Description Free-Standing Retaining Walls Neither proposed nor included in the current scope of services. Pavements Pavement thickness information for both rigid (concrete) and flexible (asphalt) pavement sections have been considered. In lieu of traffic loading provided by the design team, we anticipated traffic loading as follows: ■ Autos/light trucks: 1,000 vehicles per day ■ Light delivery and trash collection: 25 vehicles per week ■ Tractor-trailer trucks: 1 per week The pavement design period is approximately 20 years. Building Code 2021 International Building Code (IBC) Terracon should be notified if any of the above information is inconsistent with the planned construction, especially the grading limits and finished floor elevations, as modifications to our recommendations may be necessary. Site Conditions The following description of site conditions is derived from our site visit in association with the field exploration and our review of publicly available geologic and topographic maps. Item Description Parcel Information The approximate 9.35-acre project site is located east of the intersection of South 19th Avenue and West Graf Street in Bozeman, Montana. Latitude/Longitude (approximate) 45.6509° N, 111.0601° W See Site Location Existing Improvements No existing improvements on the property. Current Ground Cover Earthen, lightly vegetated, former cultivated agricultural land. Existing Topography The site is relatively flat with ground surface elevations ranging from approximately 4,970 to 4,980 feet. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 4 Item Description Geology Based on the Montana Bureau of Mines and Geology (MBMG) Geologic Map of the Bozeman Quadrangle1, the site is primarily dominated by alluvial deposits. Braid Plain Alluvium, characterized by gravel up to boulders with sand, silt, and clay, constituted the majority of the site. Towards the west, older alluvial deposits are present, featuring gravel and coarse sand. 1. Vuke, S.M., Lonn, J.D., Berg, R.B., and Schmidt, C.J., 2014, Geologic map of the Bozeman 30' x 60' quadrangle, southwestern Montana, Montana Bureau of Mines and Geology, Open-File Reports 648, 1:100,000. We also collected photographs at the time of our field exploration program. Representative photographs are provided in our Photography Log. Geotechnical Characterization We have developed a general characterization of the subsurface conditions based upon our review of the subsurface exploration, laboratory data, geologic setting and our understanding of the project. This characterization, termed GeoModel, forms the basis of our geotechnical calculations and evaluation of the site. Conditions observed at each exploration point are indicated on the individual logs. The individual logs can be found in the Exploration Results and the GeoModel can be found in the Figures attachment of this report. As part of our analyses, we identified the following model layers within the subsurface profile. For a more detailed view of the model layer depths at each boring location, refer to the GeoModel. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 5 Model Layer Layer Name General Description 1 Near Surface Clays Topsoil and lean clays, tan-brown to black-brown, partially organic, soft to medium stiff 2 Silty Gravel and Sand Gravel, silt, and sand, within a confined aquifer, gravel up to boulders, sands and fines prone to heaving into borings 3 Sandy Clay Tan-orange sandy clay present beneath aquifer, sparse gravel in upper layer Similar soil conditions were encountered across the site: an upper layer of topsoil and lean clay to approximately 2.5 feet below ground surface (bgs), then silty gravel and sand down to 25 to 30 feet bgs, and sandy clay extending to the maximum depth of exploration, 51.5 feet bgs. Based on the lithology and behavior of the soils during the exploration, the silty gravel and sand reside within a confined aquifer, restrained by the overlying clay layer. The silty gravel layer also contains boulders, noted around 8 feet bgs throughout the layer. The borings were advanced in the dry using a hollow-stem auger drilling technique that allows short term groundwater observations to be made while drilling. Groundwater seepage was encountered within 5 feet of the surface during drilling at the time of our field exploration and will likely present construction challenges. Mapping by the Natural Resources Conservation Service (NRCS) indicates a seasonal high groundwater level within 40 inches of the ground surface. Groundwater conditions may change because of seasonal variations in rainfall, runoff, and other conditions not apparent at the time of drilling; however, high groundwater is anticipated throughout the summer months based on multiple visits to the site. Long-term groundwater monitoring was outside the scope of services for this project. Seismic Site Class The seismic design requirements for buildings and other structures are based on Seismic Design Category. Site Classification is required to determine the Seismic Design Category for a structure. The Site Classification is based on the upper 100 feet of the site profile defined by a weighted average value of either shear wave velocity, standard penetration resistance, or undrained shear strength in accordance with Section 20.4 of ASCE 7 and the International Building Code (IBC). Based on the soil properties observed at the site and as described on the exploration logs and results, our professional opinion is that a Seismic Site Classification of D be considered for the project. Subsurface explorations at this site were extended to a maximum depth of 51.5 feet. The site properties below the boring depth to 100 feet were estimated based on our experience and knowledge of geologic conditions of the general area. Additional deeper borings or Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 6 geophysical testing may be performed to confirm the conditions below the current boring depth. Infiltration At three locations within the planned stormwater retention basin in the parking area, infiltration rate tests were planned to be conducted in accordance with Montana Department of Environmental Quality (MDEQ) Circular 8. However, site conditions did not allow for proper execution of the test. The most suitable drainage layer for this test, the silty gravel, resided within the confined aquifer, and was completely saturated; the procedure set forth in MDEQ Circular 8 specifies that test wells installed below groundwater level invalidate the test results. A discussion was held with DevCo’s project engineer on July 23, 2024, and it was agreed that the tests would be excluded from the exploration and testing plan. Corrosivity The table below lists the results of laboratory soluble sulfate, electrical resistivity, and pH testing. The values may be used to estimate potential corrosive characteristics of the on-site soils with respect to contact with the various underground materials which will be used for project construction. Corrosivity Test Results Summary Boring Sample Depth (feet) Soil Description Soluble Sulfate (%) Electrical Resistivity (Ω-cm) pH B-4 1 - 5 Lean Clay 0.0017 1,430 7.7 B-12 1 - 5 Lean Clay 0.0013 2,200 7.9 1. Laboratory electrical resistivity testing was performed on a saturated sample. Results of soluble sulfate testing can be classified in accordance with ACI 318 – Building Code Requirements for Structural Concrete. Numerous sources are available to characterize corrosion potential to buried metals using the parameters above. ANSI/AWWA is commonly used for ductile iron, while threshold values for evaluating the effect on steel can be specific to the buried feature (e.g., piling, culverts, welded wire reinforcement, etc.) or agency for which the work is performed. Imported fill materials may have significantly different properties than the site materials noted above and should be evaluated if expected to be in contact with metals used for construction. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 7 Consultation with a NACE certified corrosion professional is recommended for buried metals on the site. Mapping by the NRCS includes qualitative severity of corrosion to concrete and steel. Based on this source, the near-surface materials are rated “Moderate” for corrosion to concrete and “High” for corrosion of steel. Geotechnical Overview A geotechnical subsurface exploration has been performed for the proposed Graf Street Apartments project in Bozeman, Montana. This exploration included the drilling of 12 borings to depths ranging from 6.5 to 51.5 feet below existing grade. Borings B-9 and B-10, planned for field testing of infiltration rates, were omitted from the exploration plan due to the high groundwater encountered and based on our subsequent correspondence with Mr. Andrew Delia of Kimley-Horn. Boring B-13 was omitted due to soft and wet soil conditions preventing drill rig access. A breakdown of the final depths reached at each boring location is included in the Field Exploration section. Auger refusal was encountered in some of the borings, predominantly due to the presence of cobbles and boulders in the silty gravel layer of soil (Geomodel Layer 2), resulting in some of the borings being terminated before reaching the planned drilling depths. Due to a combination of relatively shallow groundwater and precipitation events, areas of wet and soft soils made safe access to the boring locations difficult. Based on our observations during the field exploration, two areas were noted across the site. One Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 8 area is located along the north border of the site, with areas extending south near the middle and on the west side of the site. Another area of wet and soft surface soil was observed along the southern edge of the site, just north of West Graf Street, near the middle and eastern side of the site. These areas were noted by increased rutting of the ground by the drill rig and support vehicle’s tires; however, the area is also generally visible in aerial imagery as well. A sketch is provided above, showing a rough approximation of the portion of the site found to be dry enough to drive the drill rig vehicles across without risk of rutting and becoming stuck, as well as approximate boundaries for the soft and wet subgrade soil. A combination of relatively shallow groundwater and a thin layer of fine-grained clay soils encountered at the existing surface of the borings is likely to complicate earthwork and site grading. Topsoil, organics, root mat, and unstable, wet, or soft areas of soils encountered will require removal and replacement of the unstable soils and a proofroll to be performed prior to any new fill being placed. Any remedial or site grading cuts made in these areas may worsen the condition of the unstable soils. Localized areas requiring remedial cuts to mitigate soft subgrade conditions may require complete removal of the surficial clay layer down to native silty gravel and replacement with Structural Fill. Temporary dewatering during construction and site grade raising within the limits of the structures and/or paved parking area construction should be considered. Additional site preparation recommendations, including subgrade improvement and fill placement, are provided in the Earthwork section. We recommend foundations for the apartment buildings, associated structures, and exterior slabs bear on the native silty gravel (Geomodel Layer 2), or a layer of Structural Fill extending to the native gravel. We recommend a separation of 3 feet between the anticipated high groundwater level and the bottom of the structure footings to reduce dewatering efforts required throughout the life of the structures and provide for an anticipated unsaturated bearing layer to support the buildings. This will help to mitigate potential long-term settlement issues associated with subsidence in areas of groundwater fluctuations. The Shallow Foundations section includes additional details. Our opinion of pavement section thickness design has been developed based on our understanding of the intended use, anticipated traffic loading, and subgrade preparation recommended herein using methodology contained in ACI 330 “Guide to Design and Construction of Concrete Parking Lots” for Portland cement concrete (PCC) pavement, and NAPA IS-109 “Design of Hot Mix Asphalt Pavements for asphalt concrete pavements, adjusted with consideration to local practice. The Pavements section includes minimum pavement component thickness. The site appears suitable for the proposed construction based upon geotechnical conditions encountered in the test borings, provided that the recommendations Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 9 presented in this report are implemented in the design and construction phases of this project. The recommendations contained in this report are based upon the results of field and laboratory testing (presented in the Exploration Results), engineering analyses, and our current understanding of the proposed project. The General Comments section provides an understanding of the report limitations. Earthwork The following presents recommendations for site preparation, excavation, subgrade preparation, soil stabilization, fill materials, compaction requirements, utility trench backfill, grading and drainage, and exterior slab design and construction. Earthwork on the project should be observed and evaluated by the Geotechnical Engineer. Evaluation of earthwork should include observation and/or testing of over-excavation, removal of existing fill, subgrade preparation, placement of engineered fills, subgrade stabilization and evaluation of other geotechnical conditions exposed during the construction of the project. Earthwork is anticipated to include clearing and grubbing, excavations, and engineered fill placement. The following sections provide recommendations for use in the preparation of specifications for the work. Recommendations include critical quality criteria, as necessary, to render the site in the state considered in our geotechnical engineering evaluation for foundations, floor slabs, and pavements. Site Preparation Prior to placing fill, existing vegetation, topsoil, and root mats should be removed. Complete stripping of the topsoil should be performed in the proposed building and parking/driveway areas. Mature trees are located near the footprint of some of the proposed buildings (primarily those on the eastern border of the property, adjacent to the drainage ditch), which may interfere with site grading, utility, and infrastructure plans. Tree root systems can remove substantial moisture from surrounding soils; where trees are removed, the full root ball and all associated dry and desiccated soils should be removed. The soil materials which contain less than 5 percent organics can be reused as engineered fill provided the material is moisture conditioned and properly compacted. Although no evidence of fill or underground facilities (such as septic tanks, cesspools, basements, and utilities) was observed during the exploration and site reconnaissance, such features could be encountered during construction. If unexpected fills or Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 10 underground facilities are encountered, such features should be removed, and the excavation thoroughly cleaned prior to backfill placement and/or construction. Excavation We anticipate that excavations for the proposed construction can be accomplished with conventional earthmoving equipment. The bottom of excavations should be thoroughly cleaned of loose soils and disturbed materials prior to backfill placement and/or construction. Excavations into the native gravel layer may be hindered by the presence of cobbles and boulders throughout the layer. Subgrade Preparation After completing the Site Preparation operations, the exposed subgrade should be scarified to a depth of 12 inches and recompacted to achieve a minimum of 98 percent of the maximum laboratory dry density in accordance with ASTM D698 in all areas below structures and paved areas. The subgrade is expected to vary from native lean clay with sand to poorly graded or silty gravel. The exposed subgrade, where excessive rutting or pumping occurs during efforts to compact the materials, should be removed and replaced or reworked and recompacted in place per our recommendations for engineered fill prior to placement of additional fill. The subgrade should be proofrolled with an adequately loaded vehicle such as a fully loaded tandem-axle dump truck. The proofrolling should be performed under the observation of the Geotechnical Engineer. Areas excessively deflecting under the proofroll should be delineated and subsequently addressed by the Geotechnical Engineer. Such areas should be removed and replaced with approved engineered fill. Excessively wet or dry material should either be removed, or moisture conditioned and recompacted. A combination of relatively shallow groundwater and a thin layer of fine-grained clay soils encountered at the existing surface of the borings may complicate pavement subgrade preparation. Topsoil, organics, root mat, and unstable, wet, or soft areas of soils encountered will require removal and replacement of the unstable soils and a proofroll to be performed prior to any new fill being placed. Any remedial or site grading cuts made in these areas may worsen the condition of the unstable soils. Localized areas requiring remedial cuts to mitigate soft subgrade conditions may require complete removal of the surficial clay layer down to native silty gravel and replacement with engineered fill to achieve a firm, stable subgrade. In order for structure footings to bear below frost depth (42 inches below grade) and maintain the recommended 3 feet of separation between the bottom of building footings or below-grade spaces such as elevator pits and the anticipated high groundwater Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 11 elevation, we recommend the site grade be raised within the limits of structure construction. To provide a stable, uniform bearing surface within the limits of structure construction, the site clay soils should be over-excavated to the depth of the native poorly graded to silty gravel and replaced with Structural Fill to the bottom of foundations. If dewatering as a method to increase the distance between the surficial soils and the water table is preferred, a long-term design solution should be in place. This approach is typically the responsibility of the project Civil Engineer, utilizing long-term groundwater data and the information presented in this report as a partial basis. Short- term mitigation of high groundwater may include the use of sumps with pumps, discharging excess water offsite. Long-term lowering of the water table is dependent on additional factors and is outside of the scope of this report. After exposed subgrades and bottoms of excavations have been prepared as recommended above, engineered fill can be placed to bring structure pads and pavement subgrade to the desired final grades. Engineered fill should be placed in accordance with the recommendations presented in subsequent sections of this report. Soil Stabilization Due to the thin layer of near-surface clays combined with the relatively shallow depths at which groundwater was encountered, subgrade mitigation is anticipated to provide a reliable stable bearing stratum. In order to achieve suitable bearing capacity, and reduce risk of potential settlement, subgrade improvement may be necessary for the planned development. Methods of subgrade improvement, as described below, could include scarification, moisture conditioning and recompaction, and removal of unstable materials and replacement with granular fill (with or without geosynthetics). The appropriate method of improvement, if required, would be dependent on factors such as schedule, weather, the size of area to be stabilized, and the nature of the instability. More detailed recommendations can be provided during construction as the need for subgrade stabilization occurs. Performing site grading operations during warm seasons and dry periods would typically help reduce the amount of subgrade stabilization required; however, the summer months typically include high groundwater levels, so mitigation of subgrades are anticipated. If the exposed subgrade is unstable during proofrolling operations, it could be stabilized using one of the methods described below. ■ Scarification and Recompaction - It may be feasible to scarify, dry, and recompact the exposed soils. The success of this procedure would depend primarily upon favorable weather and sufficient time to dry the soils. Stable subgrades likely would not be achievable if the thickness of the unstable soil is greater than about 1 foot, if the unstable soil is at or near groundwater levels, or Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 12 if construction is performed during a period of wet or cool weather when drying is difficult. ■ Structural Fill / Pit Run - The use of Structural Fill or a Pit Run gravel is a common procedure to improve subgrade stability. Typical undercut depths are project-specific, dependent on the structure and foundation type, the native subgrade, and the anticipated loading conditions among other considerations. The use of high modulus geotextiles (i.e., engineering fabric or geogrid) could also be considered after underground work such as utility construction is completed. Equipment should not be operated above the fabric or geogrid until one full lift of Structural Fill or Pit Run is placed above it. The maximum particle size of granular material placed over geotextile fabric or geogrid should not exceed 1-1/2 inches. Further evaluation of the need and recommendations for subgrade stabilization can be provided during construction as the geotechnical conditions are exposed. Fill Material Types Fill required to achieve design grade should be classified as Structural Fill, Select Fill, and General Fill. Structural Fill is material used below, or within 5 feet horizontally of structures, pavements or constructed slopes. Select Fill is used above foundation footings, beneath slabs, and as utility trench backfill. General Fill is material used to achieve grade outside of these areas, predominantly for landscaping or grading outside of the critical areas. Other fill types include crushed base course, used above native subgrade beneath pavements, and non-frost-susceptible (NFS) fill, for use where minimizing freeze-thaw induced movement beneath flatwork is critical. Reuse of On-Site Soil: Excavated on-site soil may be selectively used as engineered fill for this project, material property requirements for use as General Fill and Select Fill are noted in the table below: Property General Fill Select Fill Composition Free of deleterious material Free of deleterious material Maximum particle size 6 inches (or 2/3 of the lift thickness) 3 inches Fines content Not limited Less than 20% Passing No. 200 sieve (local standard) Plasticity Not limited Maximum plasticity index of 15 Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 13 Property General Fill Select Fill GeoModel Layer Expected to be Suitable1 1, 2, 3 22 1. Based on subsurface exploration. Actual material suitability should be determined in the field at time of construction. 2. Excluding boulders anticipated within the Geomodel layer. Imported Fill Materials: Imported fill materials should meet the following material property requirements. Regardless of its source, compacted fill should consist of approved materials that are free of organic matter and debris. Frozen material should not be used, and fill should not be placed on a frozen subgrade. Soil Type 1 USCS Classification Acceptable Parameters (for Structural Fill) Structural Fill2 GW, GP, SW, SP and dual symbols Below foundation elevation, below slab areas, raising site grade below foundation footings, and as replacement backfill Select Fill3 (sub-slab areas above footing elevation) GW, GP, SW, SP, GM, SM, GC, SC Below slab areas, interior utility trench backfill, above foundation/footing elevation, raising site grade below pavement and exterior slabs Crushed Base Course Montana Public Works Standard Specifications (MPWSS), 7th Ed, Section 02235, 3/4- inch minus Leveling course below slab above Structural or Select Fill, and as crushed aggregate base course for pavements Non-Frost Susceptible Fill (NFS) 4 GP, GW, SP, SW Below exterior flatwork critical to project to mitigate frost-action Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 14 Soil Type 1 USCS Classification Acceptable Parameters (for Structural Fill) 1. Structural, Select, and general fill should consist of approved materials free of organic matter and debris. Frozen material should not be used, and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted to the Geotechnical Engineer for evaluation prior to use on this site. Additional geotechnical consultation should be provided prior to use of uniformly graded gravel on the site. 2. Structural Fill should meet the following criteria outlined below: Gradation Percent Finer by Weight (ASTM C136) 1 ½” ............................................................................................... 100 No. 4 ............................................................................................ 30-60 No. 200 .................................................................................... 12 (max.) Liquid Limit ............................................................................... 25 (max.) Plastic Index .............................................................................. 10 (max.) 3. Select Fill, when defined as imported aggregate, should meet the following criteria outlined below: Gradation Percent Finer by Weight (ASTM C136) 3” ............................................................................................... 100 No. 4 ................................................................................................ 80 No. 40 ................................................................................................ 35 No. 200 .................................................................................... 20 (max.) Liquid Limit ............................................................................... 35 (max.) Plastic Index .............................................................................. 15 (max.) 4. Non-Frost Susceptible Fill should have no more than 5 percent passing the No. 200 sieve. Fill Placement and Compaction Requirements Structural, Select, and general fill should meet the following compaction requirements. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 15 Item Structural Fill Select Fill General Fill Maximum Lift Thickness 9 inches or less in loose thickness when heavy, self- propelled compaction equipment is used 4 to 6 inches in loose thickness when hand-guided equipment (i.e. jumping jack or plate compactor) is used Same as Structural Fill Same as Structural Fill Minimum Compaction Requirements 1,2 98% of max. below foundations, interior floor slabs 95% of max. above foundations, utility trench backfill, pavement subgrade 98% of max. below floor slabs 92% of max. Water Content Range 1 Low plasticity cohesive: -2% to +3% of optimum Granular: -3% to +3% of optimum Granular: - 3% to +1% of optimum As required to achieve min. compaction requirements 1. Maximum density and optimum water content as determined by the standard Proctor test (ASTM D 698). 2. If the granular material is a coarse sand or gravel, or of a uniform size, or has a low fines content, compaction comparison to relative density may be more appropriate. In this case, granular materials should be compacted to at least 70% relative density (ASTM D 4253 and D 4254). Materials not amenable to density testing should be placed and compacted to a stable condition observed by the Geotechnical Engineer or representative. Utility Trench Backfill All trench excavations should be made with sufficient working space to permit construction including backfill placement and compaction. Any loose, soft, or unsuitable materials encountered at the bottom of utility trench excavations should be removed and replaced with Structural Fill or bedding material in accordance with public works specifications for the utility be supported. This recommendation is particularly applicable to utility work requiring grade control and/or in areas where subsequent grade raising could cause settlement in the subgrade supporting the utility. Trench excavations within one foundation footing’s width of new or existing foundations should be evaluated by the project engineer for potential shoring requirements. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 16 Select on-site materials are considered suitable for backfill of utility and pipe trenches from 1 foot above the top of the pipe to the final ground surface, provided the material is free of organic matter and deleterious substances. Trench backfill should be mechanically placed and compacted as discussed earlier in this report. Compaction of initial lifts should be accomplished with hand-operated tampers or other lightweight compactors. Where trenches are placed beneath slabs or footings, the backfill should satisfy the gradation and expansion index requirements of engineered fill discussed in this report. Flooding or jetting for placement and compaction of backfill is not recommended. Grading and Drainage All grades must provide effective drainage away from the buildings during and after construction and should be maintained throughout the life of the development. Water retained next to the structures can result in soil movements greater than those discussed in this report. Greater movements can result in unacceptable differential floor slab and/or foundation movements, cracked slabs and walls, and roof leaks. Roofs should have gutters/drains with downspouts that discharge onto splash blocks at a distance of at least 10 feet from the buildings. Exposed ground should be sloped and maintained at a minimum 5% away from the buildings for at least 10 feet beyond the perimeter of the building. Locally, flatter grades may be necessary to transition ADA access requirements for flatwork. After construction and landscaping have been completed, final grades should be verified to document effective drainage has been achieved. Grades around the structures should also be periodically inspected and adjusted, as necessary, as part of the development’s maintenance program. Where paving or flatwork abuts a structure, a maintenance program should be established to effectively seal and maintain joints and prevent surface water infiltration. Earthwork Construction Considerations Shallow excavations for the proposed structure are anticipated to be accomplished with conventional construction equipment, and rock-breaking equipment may be required in isolated areas of boulders or cobbles. Upon completion of backfilling and grading, care should be taken to maintain the subgrade water content prior to construction of grade- supported improvements such as floor slabs and pavements. Construction traffic over the completed subgrades should be avoided. The site should also be graded to prevent ponding of surface water on the prepared subgrades or in excavations. Water collecting over or adjacent to construction areas should be removed. If the subgrade freezes, desiccates, saturates, or is disturbed, the affected material should be removed, or the Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 17 materials should be scarified, moisture conditioned, and recompacted prior to floor slab construction. The groundwater table could affect overexcavation efforts, especially for overexcavation and replacement of lower strength soils. A temporary dewatering system consisting of sumps with pumps will be necessary to achieve the recommended depth of overexcavation based on the anticipated groundwater conditions at the time of construction. Site grade raising is recommended, and if not planned, a long-term dewatering system may be required. Recommendations for long-term dewatering systems are considered outside the scope of this report. As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part 1926, Subpart P, “Excavations” and its appendices, and in accordance with any applicable local and/or state regulations. Construction site safety is the sole responsibility of the contractor who controls the means, methods, and sequencing of construction operations. Under no circumstances shall the information provided herein be interpreted to mean Terracon is assuming responsibility for construction site safety or the contractor's activities; such responsibility shall neither be implied nor inferred. Construction Observation and Testing The earthwork efforts should be observed by the Geotechnical Engineer (or others under their direction). Observation should include documentation of adequate removal of surficial materials (vegetation and topsoil), evaluation and remediation of existing fill materials, as well as proofrolling and mitigation of unsuitable areas delineated by the proofroll. Each lift of compacted fill should be tested, evaluated, and reworked, as necessary, until approved by the Geotechnical Engineer prior to placement of additional lifts. In areas of foundation excavations, the bearing subgrade should be evaluated under the guidance of the Geotechnical Engineer. If unanticipated conditions are encountered, we should prescribe mitigation options. In addition to the documentation of the essential parameters necessary for construction, the continuation of the Geotechnical Engineer into the construction phase of the project provides the continuity to maintain the Geotechnical Engineer’s evaluation of subsurface conditions, including assessing variations and associated design changes. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 18 Shallow Foundations In preparation for the planned apartment complex, the primary geotechnical concern is to provide a reliable bearing stratum, allowing sufficient bearing capacity while limiting settlement. The native gravel encountered onsite is anticipated to fulfill both of these criteria, but the underlying soils pose a challenge. Therefore, proper design, earthwork, and construction is critical. The below recommendations consider not only limiting settlement and bearing pressure, but also limiting the anticipated depth of influence of the foundation footings, so as to dissipate the new applied stresses within the silty gravel layer and avoid increasing stress in the underlying sandy clay. Properly distancing the footings above the water table will also be crucial in minimizing settlement. If the site has been prepared in accordance with the requirements noted in Earthwork, the following design parameters are applicable for shallow foundations. Design Parameters – Compressive Loads Item Description Maximum Net Allowable Bearing Pressure 1, 2 3,000 psf - foundations bearing upon native gravel or Structural Fill extending to native gravel Required Bearing Stratum 3 GeoModel Layer 2 or Structural Fill extending to properly prepared native gravel Minimum Foundation Dimensions Continuous footings – 1.5 feet wide Square footings – 2 feet square Maximum Foundation Dimensions Continuous footings – 2 feet wide Square footings – 6.5 feet square Ultimate Passive Resistance4 (equivalent fluid pressures) 460 pcf (Structural Fill) 295 pcf (Native Clays) Sliding Resistance 5 0.45 allowable coefficient of friction – native gravel or Structural Fill Minimum Embedment below Finished Grade 6 Exterior footings: 42 inches Interior footings: 24 inches Estimated Total Settlement from Structural Loads 2 Less than about 1 inch Estimated Differential Settlement 2, 7 About 1/2 of total settlement 1. The maximum net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the footing base elevation. Values assume exterior grades are no steeper than 20% within 10 feet of structure. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 19 Item Description 2. Values provided are for maximum loads noted in Project Description. Additional geotechnical consultation will be necessary if higher loads are anticipated. 3. Loose, soft, or unsuitable soils should be over-excavated and replaced per the recommendations presented in Earthwork. 4. Use of passive earth pressures require the sides of the excavation for the spread footing foundation to be nearly vertical and the concrete placed neat against these vertical faces or that the footing forms be removed and compacted Structural Fill be placed against the vertical footing face projecting up from base of footing at 30 degrees. Assumes no hydrostatic pressure. 5. Can be used to compute sliding resistance where foundations are placed on suitable soil/materials. Frictional resistance for granular materials is dependent on the bearing pressure which may vary due to load combinations. For fine-grained materials, lateral resistance using cohesion should not exceed ½ the dead load. 6. Embedment necessary to minimize the effects of frost and/or seasonal water content variations. For sloping ground, maintain depth below the lowest adjacent exterior grade within 5 horizontal feet of the structure. 7. Differential settlements are noted for equivalent-loaded foundations and bearing elevation as measured over a span of 50 feet. Foundation Construction Considerations As noted in Earthwork, the footing excavations should be evaluated under the observation of the Geotechnical Engineer. The base of all foundation excavations should be free of water and loose soil, prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing soil disturbance. Care should be taken to prevent wetting or drying of the bearing materials during construction. Excessively wet or dry material or any loose/disturbed material in the bottom of the footing excavations should be removed/reconditioned before foundation concrete is placed. Sensitive soils exposed at the surface of footing excavations may require surficial compaction with hand-held dynamic compaction equipment prior to placing Structural Fill, steel, and/or concrete. Should surficial compaction not be adequate, construction of a working surface consisting of either crushed stone or a lean concrete mud mat may be required prior to the placement of reinforcing steel and construction of foundations. Overexcavation for Structural Fill placement below footings should be conducted as shown below. The overexcavation should be backfilled up to the footing base elevation, with Structural Fill placed, as recommended in the Earthwork section. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 20 Floor Slabs Design parameters for floor slabs assume the requirements for Earthwork have been followed. Specific attention should be given to positive drainage away from the structure and positive drainage of the aggregate base beneath the floor slab. Depending upon the finished floor elevation, weak, soft to medium stiff clay soils may be observed at the floor slab subgrade level. These soils should be over-excavated by at least 2 feet and replaced with Structural or Select Fill and crushed base course for leveling. This will help to mitigate effects of consolidation, swell, or shrinkage expected of the near-surface soils. Floor Slab Design Parameters Description Floor Slab Support1 At least 18 inches of Structural or Select Fill, and a minimum of 6 inches of crushed base course for leveling Subgrade compacted to recommendations in Earthwork Estimated Modulus of Subgrade Reaction 2 200 pounds per square inch per inch (psi/in.) for point loads 1. Crushed aggregate base course in accordance with Montana Public Work Standard Specifications (MPWSS) 7th Edition, Section 02235. 2. Modulus of subgrade reaction is an estimated value based upon our experience with the subgrade condition, the requirements noted in Earthwork, and the floor slab support as noted in this table. It is provided for point loads. For large-area loads, the modulus of subgrade reaction would be lower. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 21 The use of a vapor retarder should be considered beneath concrete slabs-on-grade covered with wood, tile, carpet, or other moisture sensitive or impervious coverings, when the project includes humidity-controlled areas, or when the slab will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer should refer to ACI 302 and/or ACI 360 for procedures and cautions regarding the use and placement of a vapor retarder. Saw-cut contraction joints should be placed in the slab to help control the location and extent of cracking. For additional recommendations, refer to the ACI Design Manual. Joints or cracks should be sealed with a waterproof, non-extruding compressible compound specifically recommended for heavy duty concrete pavement and wet environments. Where floor slabs are tied to perimeter walls or turn-down slabs to meet structural or other construction objectives, our experience indicates differential movement between the walls and slabs will likely be observed in adjacent slab expansion joints or fl oor slab cracks beyond the length of the structural dowels. The Structural Engineer should account for potential differential settlement through use of sufficient control joints, appropriate reinforcing or other means. Floor Slab Construction Considerations Finished subgrade, within and for at least 10 feet beyond the floor slab, should be protected from traffic, rutting, or other disturbance and maintained in a relatively moist condition until floor slabs are constructed. If the subgrade should become damaged or desiccated prior to construction of floor slabs, the affected material should be removed, and Structural Fill or Select Fill should be added to replace the resulting excavation. Final conditioning of the finished subgrade should be performed immediately prior to placement of the floor slab support course. The Geotechnical Engineer should observe the condition of the floor slab subgrades immediately prior to placement of the floor slab support course, reinforcing steel, and concrete. Attention should be paid to high traffic areas that were rutted and disturbed earlier, and to areas where backfilled trenches are located. Below-Grade Structures We anticipate the final site plan for the complex will include elevator pits for the main apartment buildings, underground utility pipes, and possibly a pool, based on a review of preliminary site plans. Consideration for these structures in this report is limited to the following discussion on lateral earth pressures. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 22 Lateral Earth Pressures Design Parameters Structures with unbalanced backfill levels on opposite sides should be designed for earth pressures at least equal to values indicated in the following table. Earth pressures will be influenced by structural design of the walls, conditions of wall restraint, methods of construction, and/or compaction and the strength of the materials being restrained. Three wall restraint conditions are shown in the diagram below. Active earth pressure is commonly used for design of free-standing cantilever retaining walls and assumes wall movement away from the backfill zone. The “at-rest” condition assumes no wall movement and is commonly used for basement walls, loading dock walls, or other walls restrained at the top. The “passive” condition assumes wall movement into the backfill zone, and is commonly used for thrust block design. The recommended design lateral earth pressures do not include a factor of safety and do not provide for possible hydrostatic pressure on the walls (unless stated). Lateral Earth Pressure Design Parameters Earth Pressure Condition 1 Coefficient for Backfill Type 2 Surcharge Pressure 3 p1 (psf) Equivalent Fluid Pressures (psf) 2,4 Unsaturated 5 Submerged 5 Active (Ka) Granular - 0.27 Fine Grained - 0.41 (0.27)S (0.41)S (34)H (49)H (79)H (86)H At-Rest (Ko) Granular - 0.43 Fine Grained - 0.58 (0.43)S (0.58)S (53)H (69)H (89)H (96)H Passive (Kp) Granular – 3.69 Fine Grained – 2.46 (3.69)S (2.46)S (460)H (295)H (293)H (204)H 1. For active earth pressure, wall must rotate about base, with top lateral movements 0.002 H to 0.004 H, where H is wall height. For passive earth Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 23 Lateral Earth Pressure Design Parameters Earth Pressure Condition 1 Coefficient for Backfill Type 2 Surcharge Pressure 3 p1 (psf) Equivalent Fluid Pressures (psf) 2,4 Unsaturated 5 Submerged 5 pressure, wall must move horizontally to mobilize resistance. Fat clay or other expansive soils should not be used as backfill behind the wall. 2. Uniform, horizontal backfill, with a maximum unit weight of 120 pcf for cohesive soils and 125 pcf for granular soils. 3. Uniform surcharge, where S is surcharge pressure. 4. Loading from heavy compaction equipment is not included. 5. To achieve “Unsaturated” conditions, follow guidelines in Subsurface Drainage for Below-Grade Walls below and considerations for mitigating high groundwater previously mentioned. “Submerged” conditions are recommended when drainage behind walls is not incorporated into the design, or for structures extending beneath the water table. Backfill placed against structures should consist of granular soils or low plasticity cohesive soils. For the granular values to be valid, the granular backfill must extend out and up from the base of the wall at an angle of at least 45 degrees from vertical for the active case. Footings, floor slabs or other loads bearing on backfill behind walls may have a significant influence on the lateral earth pressure. Placing footings within wall backfill and in the zone of active soil influence on the wall should be avoided unless structural analyses indicate the wall can safely withstand the increased pressure. The lateral earth pressure recommendations given in this section are applicable to the design of rigid retaining walls subject to slight rotation, such as cantilever, or gravity type concrete walls. These recommendations are not applicable to the design of modular block - geogrid reinforced backfill walls (also termed MSE walls). Recommendations covering these types of wall systems are beyond the scope of services for this assignment. However, we would be pleased to develop a proposal for evaluation and design of such wall systems upon request. Subsurface Drainage for Below-Grade Walls A perforated rigid plastic drain line installed behind the base of walls and extends below adjacent grade is recommended to prevent hydrostatic loading on the walls. The invert of a drain line around a below-grade building area or exterior retaining wall should be placed near foundation bearing level. The drain line should be sloped to provide positive gravity drainage to daylight or to a sump pit and pump. The drain line should be surrounded by clean, free-draining granular material having less than 5% passing the Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 24 No. 200 sieve, such as No. 57 aggregate. The free-draining aggregate should be encapsulated in a filter fabric. The granular fill should extend to within 2 feet of final grade, where it should be capped with compacted cohesive fill to reduce infiltration of surface water into the drain system. As an alternative to free-draining granular fill, a prefabricated drainage structure may be used. A prefabricated drainage structure is a plastic drainage core or mesh which is covered with filter fabric to prevent soil intrusion and is fastened to the wall prior to placing backfill. If high groundwater conditions are not mitigated, as discussed previously, this subsurface drainage system will not be sufficient to provide unsaturated conditions. In order to achieve unsaturated conditions, a permanent dewatering system or other means of mitigating high groundwater, and maintaining the recommended 3-foot distance between the bottom of the structure and the groundwater table, will be necessary. Pavements General Pavement Comments The pavement section recommendations provided are based on the subsurface profile and laboratory testing of bulk samples obtained from the subgrade encountered. Pavement designs are provided for the traffic conditions and pavement life conditions as noted in Project Description and in the following sections of this report. A critical aspect of pavement performance is site preparation. Pavement designs noted in this section must be applied to the site which has been prepared as recommended in the Earthwork section. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 25 Pavement Design Parameters Designs for minimum thicknesses for new pavement sections for this project have been based on the procedures outlined in the 1993 Guideline for Design of Pavement Structures by the American Association of State Highway and Transportation Officials (AASHTO-1993). Pavement design methods are intended to provide structural sections with adequate thickness over a particular subgrade such that wheel loads are reduced to a level the subgrade can support. The support characteristics of the subgrade for pavement design do not account for shrink/swell movements of the anticipated clay subgrade soils. Thus, the pavement may be adequate from a structural standpoint, yet still experience cracking and deformation due to shrink/swell related movement of the subgrade. To analyze the pavement subgrade support, a composite bulk sample of the controlling subgrade material (Geomodel layer 1, the native surficial clays) was collected and a laboratory-soaked, single-point California Bearing Ratio (CBR) test was performed. The sample tested was compacted to approximately 95% of the maximum dry density at optimum moisture content, both determined through the standard proctor testing method. The resulting CBR value was calculated to be 3.1 percent. For purposes of analysis, based on the combination of field and laboratory testing results for the controlling subgrade native clay, a design CBR value of 3 percent was utilized in the analysis discussed below. The analysis assumes the pavement will be placed over the soil layer discussed above. If the pavement is to bear onto another layer or material, either due to overexcavation and replacement or as a result of changing site grade in the pavement area, the thickness values provided are not valid. If the bearing material is to be changed, we should be contacted to provide updated thickness recommendations. Based on previous experience with similar projects, we anticipate primary traffic will consist of personal automobiles or light trucks with limited daily light delivery vehicles (FedEx, UPS, similar) along with weekly trash collection. The anticipated daily traffic is to consist of approximately 1,000 light truck/passenger cars passages per day. We have assumed that twenty light delivery vehicles, five garbage trucks, and one semi-tractor trailer per week will also be accounted for to service the apartment complex. Based on these assumptions, an estimated 30,000 ESALs represent the design traffic intensity for the automobile parking areas and an estimated 175,000 ESALs for the drive lane pavements over a 20-year design period. For analysis an initial serviceability index of 4.2, a terminal serviceability index of 2.0, standard deviation of 0.45, and reliability of 80 percent have been utilized for section thickness development. A modulus of subgrade reaction of 95 pci was used for the PCC pavement designs, and a resilient modulus of 5,000 psi was used for the design of AC pavements. The values were based upon the laboratory CBR results and correlated based on published data and Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 26 our experience with the lean clay subgrade soils and our understanding of the quality of the subgrade as prescribed by the Site Preparation conditions as presented in Earthwork. A modulus of rupture of 630 psi was used for pavement concrete. Pavement Section Thicknesses The following table provides our opinion of minimum thickness for AC sections: Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 27 Asphaltic Concrete Design Layer Thickness (inches) Automobile Parking Thickness (30k ESAL) (inches) 1 Truck Drive Lane Thickness (175k ESAL) (inches) 1 AC 2 3 4 Aggregate Base3 8 10 1. See Project Description for more specifics regarding traffic assumptions. 2. All materials should meet the current requirements set by the City of Bozeman’s modifications to the Montana Public Works Standard Specifications (MPWSS), 7th edition, Section 02510. 3. Crushed Base Course should conform to Montana Public Works Specification 02235 “Crushed Base Course”, based on the Table of Gradation for 3/4-inch minus product in the table above. The following table provides our estimated minimum thickness of PCC pavements. Portland Cement Concrete Design Layer Automobile Parking Thickness (inches) Truck Drive Lane Thickness (inches) Dumpster Pad Approach Thickness (inches) PCC 1 5 5 7 Aggregate Base2 4 4 4 1. PCC should conform to the Montana Public Works Specification 02515 “Portland Cement Concrete Pavement”, should have minimum 28-day strength of 4,500 psi, and minimum modulus of rupture of 630 psi. 2. Crushed Base Course should conform to Montana Public Works Specification 02235 “Crushed Base Course”, based on the Table of Gradation for 3/4-inch minus product in the table above. Migration of fines into the aggregate base course layer will reduce the support characteristics of the base and decrease performance of the pavement section. The placement of a geotextile separation fabric, such as a Mirafi 140N or equivalent, between the fine-grained subgrade and the aggregate base course to improve the constructability and extend the pavement’s service life should be considered for the above sections. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 28 Areas for parking heavy vehicles, concentrated turn areas, and start/stop maneuvers could require thicker pavement sections, where rigid pavements are not employed. Edge restraints (i.e. concrete curbs or aggregate shoulders) should be planned along curves and areas of maneuvering vehicles. The pavement sections presented in the previous tables are based on design traffic loading assumed; as such, assumptions made regarding expected load volumes and traffic categories should be reviewed for consistency with other similar facilities. These sections or partial sections thereof are not to be considered a construction platform for sustaining heavier and higher frequency axle/wheel loads than have been considered in the pavement design for a completed section. Although not required for structural support, a minimum 4-inch thick base course layer is recommended for PCC pavements to help reduce potential for slab curl, shrinkage cracking, and subgrade pumping through joints. Proper joint spacing will also be required to prevent excessive slab curling and shrinkage cracking. Joints should be sealed to prevent entry of foreign material and doweled where necessary for load transfer. PCC pavement details for joint spacing, joint reinforcement, and joint sealing should be prepared in accordance with ACI 330 and ACI 325. Where practical, we recommend early-entry cutting of crack-control joints in PCC pavements. Cutting of the concrete in its “green” state typically reduces the potential for micro-cracking of the pavements prior to the crack control joints being formed, compared to cutting the joints after the concrete has fully set. Micro-cracking of pavements may lead to crack formation in locations other than the sawed joints, and/or reduction of fatigue life of the pavement. Openings in pavements, such as decorative landscaped areas, are sources for water infiltration into surrounding pavement systems. Water can collect in the islands and migrate into the surrounding subgrade soils thereby degrading support of the pavement. Islands with raised concrete curbs, irrigated foliage, and low permeability near-surface soils are particular areas of concern. The civil design for the pavements with these conditions should include features to restrict or collect and discharge excess water from the islands. Examples of features are edge drains connected to the stormwater collection system, longitudinal subdrains, or other suitable outlets and impermeable barriers preventing lateral migration of water such as a cutoff wall installed to a depth below the pavement structure. Pavement Drainage Pavements should be sloped to provide rapid drainage of surface water. Water allowed to pond on or adjacent to the pavements could saturate the subgrade and contribute to premature pavement deterioration. In addition, the pavement subgrade should be graded to provide positive drainage within the granular base section. Appropriate sub- Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 29 drainage or connection to a suitable daylight outlet should be provided to remove water from the granular subbase. Based on the possibility of shallow and/or perched groundwater, we recommend installing a pavement subdrain system to control groundwater, improve stability, and improve long-term pavement performance. We recommend at least 6 inches of free-draining granular material be placed beneath the pavements. The use of a free draining granular base will also reduce the potential for frost action. We recommend pavement subgrades be crowned at least 2% to promote the flow of water towards the subdrains, and to reduce the potential for ponding of water on the subgrade. The design recommendations for the subdrains are provided in the following table: Subdrain Design Recommendations Item Value Free Draining Granular Base Thickness below Pavement 6 inches of material meeting No. 57 aggregate specifications Minimum Drainpipe Diameter 4 inches Drain Trench Width 16 inches or greater to provide minimum 6-inch annulus of drainage aggregate around drainpipe. Invert Depth below Subgrade Elevation 3½ feet Maximum Drainpipe Spacing 50 feet Subdrain Trench Backfill Material No. 57 aggregate or 3/4-inch aggregate The subdrains should be hydraulically connected to the free-draining granular base layer. Subdrains should be sloped to provide positive gravity drainage to reliable discharge points such as a stormwater detention basin. Periodic maintenance of subdrains is required for long-term proper performance. Pavement Maintenance The pavement sections represent minimum recommended thicknesses and, as such, periodic upkeep should be anticipated. Preventive maintenance should be planned and provided for through an on-going pavement management program. Maintenance activities are intended to slow the rate of pavement deterioration and to preserve the pavement investment. Pavement care consists of both localized (e.g., crack and joint sealing and patching) and global maintenance (e.g., surface sealing). Additional engineering consultation is recommended to determine the type and extent of a cost- Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 30 effective program. Even with periodic maintenance, some movements and related cracking may still occur, and repairs may be required. Pavement performance is affected by its surroundings. In addition to providing preventive maintenance, the civil engineer should consider the following recommendations in the design and layout of pavements: ■ Final grade adjacent to paved areas should slope down from the edges at a minimum 2%. ■ Subgrade and pavement surfaces should have a minimum 2% slope to promote proper surface drainage. ■ Install pavement drainage systems surrounding areas anticipated for frequent wetting. ■ Install joint sealant and seal cracks immediately. ■ Seal all landscaped areas in or adjacent to pavements to reduce moisture migration to subgrade soils. ■ Place compacted, low permeability backfill against the exterior side of curb and gutter. ■ Place curb, gutter and/or sidewalk directly on clay subgrade soils rather than on unbound granular base course materials. Frost Considerations The soils on this site are frost susceptible, and small amounts of water can affect the performance of the slabs-on-grade, sidewalks, and pavements. Exterior slabs should be anticipated to heave during winter months. If frost action needs to be eliminated in critical areas, we recommend the use of non-frost susceptible (NFS) fill or structural slabs (for instance, structural stoops in front of building doors). Placement of NFS material in large areas may not be feasible; however, the following recommendations are provided to help reduce potential frost heave: ■ Provide surface drainage away from the building and slabs, and toward the site drainage system. ■ Install drains around the perimeter of the building, stoops, below exterior slabs and pavements, and connect them to the site drainage system. ■ Grade clayey subgrades so groundwater potentially perched in overlying fill or aggregate base, slope toward a site drainage system. ■ Place NFS fill as backfill beneath slabs and pavements critical to the project. ■ Place a 3 horizontal to 1 vertical (3H:1V) transition zone between NFS fill and other soils. ■ Place NFS materials in critical sidewalk areas. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 31 As an alternative to extending NFS fill to the full frost depth, consideration can be made to placing extruded polystyrene or cellular concrete under a buffer of at least 2 feet of NFS material. General Comments Our analysis and opinions are based upon our understanding of the project, the geotechnical conditions in the area, and the data obtained from our site exploration. Variations will occur between exploration point locations or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. Terracon should be retained as the Geotechnical Engineer, where noted in this report, to provide observation and testing services during pertinent construction phases. If variations appear, we can provide further evaluation and supplemental recommendations. If variations are noted in the absence of our observation and testing services on-site, we should be immediately notified so that we can provide evaluation and supplemental recommendations. Our Scope of Services does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. Our services and any correspondence are intended for the sole benefit and exclusive use of our client for specific application to the project discussed and are accomplished in accordance with generally accepted geotechnical engineering practices with no third- party beneficiaries intended. Any third-party access to services or correspondence is solely for information purposes to support the services provided by Terracon to our client. Reliance upon the services and any work product is limited to our client a nd is not intended for third parties. Any use or reliance of the provided information by third parties is done solely at their own risk. No warranties, either express or implied, are intended or made. Site characteristics as provided are for design purposes and not to estimate excavation cost. Any use of our report in that regard is done at the sole risk of the excavating cost estimator as there may be variations on the site that are not apparent in the data that could significantly effect excavation cost. Any parties charged with estimating excavation costs should seek their own site characterization for specific purposes to obtain the specific level of detail necessary for costing. Site safety and cost estimating including excavation support and dewatering requirements/design are the responsibility of others. Construction and site development have the potential to affect adjacent properties. Such impacts can include damages due to vibration, modification of groundwater/surface water flow during construction, foundation movement due to undermining or subsidence Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials 32 from excavation, as well as noise or air quality concerns. Evaluation of these items on nearby properties are commonly associated with contractor means and methods and are not addressed in this report. The owner and contractor should consider a preconstruction/precondition survey of surrounding development. If changes in the nature, design, or location of the project are planned, our conclusions and recommendations shall not be considered valid unless we review the changes and either verify or modify our conclusions in writing. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Figures Contents: GeoModel (4 pages) 4,958 4,959 4,960 4,961 4,962 4,963 4,964 4,965 4,966 4,967 4,968 4,969 4,970 4,971 4,972 ELEVATION (MSL) (feet)Layering shown on this figure has been developed by the geotechnical engineer for purposes of modeling the subsurface conditions asrequired for the subsequent geotechnical engineering for this project.Numbers adjacent to soil column indicate depth below ground surface. NOTES: B-1 B-7B-14 Legend This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions. GeoModel South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Graf Street Apartments 2110 Overland Ave Ste 124 Billings, MT First Water Observation Groundwater levels are temporal. The levels shown are representative ofthe date and time of our exploration. Significant changes are possibleover time.Water levels shown are as measured during and/or after drilling. Insome cases, boring advancement methods mask the presence/absenceof groundwater. See individual logs for details. Topsoil Lean Clay with Sand Silty Gravel withSand Sandy Lean Clay Poorly-gradedGravel with Silt andSand Model Layer Layer Name General Description 1 Topsoil and lean clays, tan-brown to black-brown, partiallyorganic, soft to medium stiff 3 Tan-orange sandy clay present beneath aquifer, sparsegravel in upper layer 2 Gravel, silt, and sand, within a confined aquifer, gravel upto boulders, sands and fines prone to heaving into borings Near Surface Clays Sandy Clay Silty Gravel andSand 1 2 3 2 2.5 2.5 1010.2 13 1 2 2.5 2.5 11.5 1 2 2.5 2.5 11.5 4,920 4,925 4,930 4,935 4,940 4,945 4,950 4,955 4,960 4,965 4,970 4,975 ELEVATION (MSL) (feet)Layering shown on this figure has been developed by the geotechnical engineer for purposes of modeling the subsurface conditions asrequired for the subsequent geotechnical engineering for this project.Numbers adjacent to soil column indicate depth below ground surface. NOTES: B-4 B-8 B-15 Legend This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions. GeoModel South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Graf Street Apartments 2110 Overland Ave Ste 124 Billings, MT First Water Observation Groundwater levels are temporal. The levels shown are representative ofthe date and time of our exploration. Significant changes are possibleover time.Water levels shown are as measured during and/or after drilling. Insome cases, boring advancement methods mask the presence/absenceof groundwater. See individual logs for details. Topsoil Lean Clay with Sand Poorly-gradedGravel with Silt andSand Clayey Gravel Sandy Lean Clay Silty Sand Silty Gravel withSand Silty Clayey Gravelwith Sand Model Layer Layer Name General Description 1 Topsoil and lean clays, tan-brown to black-brown, partiallyorganic, soft to medium stiff 3 Tan-orange sandy clay present beneath aquifer, sparsegravel in upper layer 2 Gravel, silt, and sand, within a confined aquifer, gravel upto boulders, sands and fines prone to heaving into borings Near Surface Clays Sandy Clay Silty Gravel andSand 1 2 3 2.5 2 29 51.5 1 24 2.5 6.5 1 2 4.5 4.5 26.5 4,948 4,950 4,952 4,954 4,956 4,958 4,960 4,962 4,964 4,966 4,968 4,970 4,972 4,974 4,976 ELEVATION (MSL) (feet)Layering shown on this figure has been developed by the geotechnical engineer for purposes of modeling the subsurface conditions asrequired for the subsequent geotechnical engineering for this project.Numbers adjacent to soil column indicate depth below ground surface. NOTES: B-2 B-5 B-11 Legend This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions. GeoModel South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Graf Street Apartments 2110 Overland Ave Ste 124 Billings, MT First Water Observation Groundwater levels are temporal. The levels shown are representative ofthe date and time of our exploration. Significant changes are possibleover time.Water levels shown are as measured during and/or after drilling. Insome cases, boring advancement methods mask the presence/absenceof groundwater. See individual logs for details. Topsoil Lean Clay with Sand Silty Gravel withSand Gravelly Lean Claywith Sand Poorly-gradedGravel with Sand Sandy Lean Clay Silty Clayey Gravelwith Sand Model Layer Layer Name General Description 1 Topsoil and lean clays, tan-brown to black-brown, partiallyorganic, soft to medium stiff 3 Tan-orange sandy clay present beneath aquifer, sparsegravel in upper layer 2 Gravel, silt, and sand, within a confined aquifer, gravel upto boulders, sands and fines prone to heaving into borings Near Surface Clays Sandy Clay Silty Gravel andSand 1 2 2 2 8.9 1 2 3 2 0.75 25 26.5 1 2 3.5 2.5 20 4,950 4,955 4,960 4,965 4,970 4,975 4,980 ELEVATION (MSL) (feet)Layering shown on this figure has been developed by the geotechnical engineer for purposes of modeling the subsurface conditions asrequired for the subsequent geotechnical engineering for this project.Numbers adjacent to soil column indicate depth below ground surface. NOTES: B-3 B-6 B-12 Legend This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions. GeoModel South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Graf Street Apartments 2110 Overland Ave Ste 124 Billings, MT First Water Observation Groundwater levels are temporal. The levels shown are representative ofthe date and time of our exploration. Significant changes are possibleover time.Water levels shown are as measured during and/or after drilling. Insome cases, boring advancement methods mask the presence/absenceof groundwater. See individual logs for details. Topsoil Lean Clay with Sand Poorly-gradedGravel with Silt andSand Silty Gravel withSand Gravelly Lean Claywith Sand Clayey Gravel withSand Lean Clay withGravel Model Layer Layer Name General Description 1 Topsoil and lean clays, tan-brown to black-brown, partiallyorganic, soft to medium stiff 3 Tan-orange sandy clay present beneath aquifer, sparsegravel in upper layer 2 Gravel, silt, and sand, within a confined aquifer, gravel upto boulders, sands and fines prone to heaving into borings Near Surface Clays Sandy Clay Silty Gravel andSand 1 2 3.5 2 26.5 1 2 3 2.5 7 24 26.5 1 2 3 2.5 19.1 Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Attachments Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Exploration and Testing Procedures Field Exploration Number of Borings Approximate Boring Depth (feet) Location B-1 13.0 Building 2 B-2 8.5 Building 10 B-3 26.5 Buildings 8 and 9 B-4 51.5 Building 2 B-5 26.5 Building 1 B-6 26.5 Building 7 B-7 11.5 Building 3 B-8 6.5 Stormwater Detention Chamber B-11 20.0 Building 5 B-12 19.1 Building 6 B-14 11.5 Buildings 2 and 3 B-15 26.5 Building 4 Boring Layout and Elevations: Terracon personnel provided the boring layout using handheld GPS equipment (estimated horizontal accuracy of about ±10 feet) and referencing existing site features. Approximate ground surface elevations were obtained by interpolation from the provided grading plan. If surface elevations and a more precise boring layout are desired, we recommend the borings be surveyed. Due to soft, wet ground conditions at the time of drilling, Borings B-9, B-10, and B-13 could not be safely accessed, and were omitted from the drilling program. Subsurface Exploration Procedures: Our exploration was conducted from July 22 to July 25, 2024, when we advanced the borings with a subcontracted, truck-mounted BK-81 drill rig operated by HazTech Drilling. The borings were advanced using continuous-flight, hollow-stem augers. In general, four samples were obtained in the upper 10 feet of each boring, and at intervals of 5 feet thereafter. Bulk samples of the upper 5 feet in the profile were collected, as needed. In the thin-walled tube sampling procedure, a thin- walled, seamless steel tube with a sharp cutting edge was pushed hydraulically into the soil to obtain a relatively undisturbed sample. In the split-barrel sampling procedure, a standard 2-inch outer diameter, split-barrel sampling spoon was driven into the ground Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials by a 140-pound automatic hammer falling a distance of 30 inches. The number of blows required to advance the sampling spoon the last 12 inches of a normal 18-inch penetration is recorded as the Standard Penetration Test (SPT) resistance value. The SPT resistance values, also referred to as N-values, are indicated on the boring logs at the test depths. For safety purposes, all borings were backfilled with auger cuttings after their completion. We also observed the boreholes while drilling and at the completion of drilling for the presence of groundwater. The groundwater levels are shown on the attached boring logs. The sampling depths, penetration distances, and other sampling information were recorded on the field boring logs. The samples were placed in appropriate containers and taken to our soil laboratory for testing and classification by a Geotechnical Engineer. Our exploration team prepared field boring logs as part of the drilling operations. These field logs included visual classifications of the materials observed during drilling and our interpretation of the subsurface conditions between samples. Final boring logs were prepared from the field logs. The final boring logs represent the Geotechnical Engineer's interpretation of the field logs and include modifications based on observations and tests of the samples in our laboratory. Laboratory Testing The project engineer reviewed the field data and assigned laboratory tests. The laboratory testing program included the following types of tests: ■ Moisture Content ■ Dry Unit Weight ■ Atterberg Limits ■ Grain Size Distribution ■ One-Dimensional Swell-Consolidation ■ Unconfined Compressive Strength ■ Moisture-Density Relationship ■ California Bearing Ratio The laboratory testing program included examination of soil samples by an engineer. Based on the results of our field and laboratory programs, we described and classified the soil samples in accordance with the Unified Soil Classification System. Other Testing: Soil analytical testing for water soluble sulfated, minimum electrical resistivity, and pH were performed by Energy Laboratories in Billings, Montana. The report provided by Energy Labs is attached. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Photography Log Staking, March 25, 2024 – Existing monitoring well near B-5, looking north. Staking, March 25, 2024 – Surface water noted near vicinity of B-14. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Initial Mobilization, April 1, 2024 – Rutting due to company pickup, between borings B-6 and B-12. Site reconnaissance, July 18, 2024 – Area of Boring B-3, looking northeast. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Site reconnaissance, July 18, 2024 – Area of Boring B-11, looking south, looking for signs of rutting or excessive moisture or softness. Field exploration, July 23, 2024 – Setting up over Boring B-4, looking south. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Field exploration, July 23, 2024 – Rutting encountered just east of Boring B-5. Field exploration, July 24, 2024 – Navigating to western portion of site, from area of Boring B-6 to B-12, looking east. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Site Location and Exploration Plans Contents: Site Location Plan Exploration Plan Note: All attachments are one page unless noted above. Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Note to Preparer: This is a large table with outside borders. Just click inside the table above this text box, then paste your GIS Toolbox image. When paragraph markers are turned on you may notice a line of hidden text above and outside the table – please leave that alone. Limit editing to inside the table. The line at the bottom about the general location is a separate table line. You can edit it as desired, but try to keep to a single line of text to avoid reformatting the page. Site Location DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Note to Preparer: This is a large table with outside borders. Just click inside the table above this text box, then paste your GIS Toolbox image. When paragraph markers are turned on you may notice a line of hidden text above and outside the table – please leave that alone. Limit editing to inside the table. The line at the bottom about the general location is a separate table line. You can edit it as desired, but try to keep to a single line of text to avoid reformatting the page. Exploration Plan DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS Exploration and Laboratory Results Contents: Boring Logs (13 pages) Atterberg Limits Grain Size Distribution Consolidation/Swell Unconfined Compressive Strength Moisture Density Relationship California Bearing Ratio Energy Labs Corrosivity Testing Report (8 pages) Note: All attachments are one page unless noted above. 4970.3 4968.8 4961.34961.1 4958.3 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat. LEAN CLAY WITH SAND (CL), black to brown, moist,medium stiff SILTY GRAVEL WITH SAND (GM), brown, wet, dense cobbles to boulders, slow auger progress, dancing in holeand grinding SANDY LEAN CLAY (CL), brown, wet POORLY GRADED GRAVEL WITH SILT AND SAND(GP-GM), brown, wetboulders, slower progress Auger Refusal at 13 Feet Boring Log No. B-1 Water LevelObservationsDepth (Ft.)5 10 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer37.6 18.1 15.2 19.6 15.9 1.0 2.5 10.010.2 13.0 2-3-3N=6 3-11-10N=21 19-28-25N=53 25-37-31N=68 15-11-19N=30 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-25-2024 Boring Completed07-25-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4971.3 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6511° Longitude: -111.0599° Depth (Ft.)Field TestResults1 2 3 2 4973.8 4972.8 4965.9 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat LEAN CLAY WITH SAND (CL), black brown to graybrown, moist, soft, organic SILTY GRAVEL WITH SAND (GM), fine to coarsegrained, dark brown to brown, wet, medium dense todense boulders, severe grinding and slow progress to refusalpoint Auger Refusal at 8.9 Feet Boring Log No. B-2 Water LevelObservationsDepth (Ft.)5 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer18.5 19.0 1.0 2.0 8.9 1-3-3N=6 10-15-20N=35 11-20-18N=38 16-23-34N=57 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-25-2024 Boring Completed07-25-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4974.8 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6504° Longitude: -111.0600° Depth (Ft.)Field TestResults1 2 4977.9 4976.4 4963.9 4951.9 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat noted in upper 6 inches. LEAN CLAY WITH SAND (CL), dark brown, moist,medium stiff POORLY GRADED GRAVEL WITH SILT AND SAND(GP-GM), fine to coarse grained, brown to dark brown,moist to wet, dense to very dense SILTY GRAVEL WITH SAND (GM), fine to coarsegrained, brown to orange-brown, wet, very dense comparatively smoother drilling, still some grinding ofauger medium dense Boring Terminated at 26.5 Feet Boring Log No. B-3 Water LevelObservationsDepth (Ft.)5 10 15 20 25 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer13.9 18.7 15.3 13.9 20.1 36.8 25.5 0.5 2.0 14.5 26.5 2-4-3N=7 13-18-22N=40 14-23-22N=45 19-20-41N=61 28-30-28N=58 23-50/5" 35-50/4" 17-9-15N=24 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-22-2024 Boring Completed07-22-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4978.4 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6497° Longitude: -111.0600° Depth (Ft.)Field TestResults1 2 4972 4970.5 4948 4943.5 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat noted in upper 6 inches. LEAN CLAY WITH SAND (CL), dark brown to tan brown,moist, soft POORLY GRADED GRAVEL WITH SILT AND SAND(GP-GM), with cobbles and boulders, fine to coarsegrained, dark brown, wet, dense grinding very dense suspected boulders, slow progress, auger dancing in hole CLAYEY GRAVEL (GC), fine to coarse grained, brown toorange-brown, wet, very dense SANDY LEAN CLAY (CL), low to medium plasticity, tanto orange brown, wet, stiff Boring Log No. B-4 Water LevelObservationsDepth (Ft.)5 10 15 20 25 30 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer26.9 16.3 15.8 26.4 17.0 17.4 19.8 15.8 0.5 2.0 24.5 29.0 2-2-2N=4 10-16-15N=31 20-18-17N=35 13-22-34N=56 16-42-30N=72 13-33-38N=71 29-35-50/5" 17-35-36N=71 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-23-2024 Boring Completed07-23-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4972.5 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6508° Longitude: -111.0594° Depth (Ft.)Field TestResults1 2 3 4931.5 4930.5 4921 SANDY LEAN CLAY (CL), low to medium plasticity, tanto orange brown, wet, stiff (continued) very stiff SILTY SAND (SM), black to brown, wet, very stiff,possible heaved sands. SANDY LEAN CLAY (CL), medium plasticity, orangebrown, wet, very stiff Boring Terminated at 51.5 Feet Boring Log No. B-4 Water LevelObservationsDepth (Ft.)35 40 45 50 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer592050 37.5 33.2 39.2 36.8 39.8 44.2 82 45-25-2041.0 42.0 51.5 1-6-7N=13 6-8-10N=18 7-12-14N=26 5-7-10N=17 5-7-11N=18 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-23-2024 Boring Completed07-23-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4972.5 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6508° Longitude: -111.0594° Depth (Ft.)Field TestResults3 4974.24973.95 4972.2 4950.24949.7 4948.2 TOPSOIL, brown, dark brown, moist to dry, sandy claywith organics and root mat noted in upper 6 inches. LEAN CLAY WITH SAND (CL), black, moist, stiff GRAVELLY LEAN CLAY WITH SAND (CL), black, moistgrinding SILTY GRAVEL WITH SAND (GM), fine to coarsegrained, black to brown, wet, dense very dense liquidy silty sand auger returns POORLY GRADED GRAVEL WITH SAND (GP), fine tocoarse grained, black, wet, loose SANDY LEAN CLAY (CL), tan to brown, wet, mediumstiff Boring Terminated at 26.5 Feet Boring Log No. B-5 Water LevelObservationsDepth (Ft.)5 10 15 20 25 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer82 17.0 16.1 21.9 13.4 24.3 27.0 51.3 57-28-29 0.50.8 2.5 24.525.0 26.5 2-3-9N=12 16-25-25N=50 19-50/2" 23-30-27N=57 22-26-47N=73 22-38-50/2" 21-39-43N=82 2-4-4N=8 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-23-2024 Boring Completed07-23-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4974.7 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6503° Longitude: -111.0594° Depth (Ft.)Field TestResults1 2 3 4978.8 4972.8 4961.8 4955.8 4953.3 CLAYEY SAND (CL), low plasticity, dark brown, dry, stiff GRAVELLY LEAN CLAY WITH SAND (CL), fine to coarsegrained, low plasticity, dark brown, moist to wet, denseto very dense very dense POORLY GRADED GRAVEL WITH SILT AND SAND(GP-GM), coarse grained, rounded to subrounded, blackto brown, wet, dense cobbles to boulders, very slow progress, auger grinding dense CLAYEY GRAVEL (GC), fine to coarse grained, brown tomulticolored, wet, dense to very dense LEAN CLAY WITH GRAVEL (CL), grey-brown totan-brown, wet, stiff Boring Terminated at 26.5 Feet Boring Log No. B-6 Water LevelObservationsDepth (Ft.)5 10 15 20 25 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer10.5 19.8 16.8 16.7 19.2 18.4 46.4 1.0 7.0 18.0 24.0 26.5 3-11-8N=19 19-21-29N=50 37-40-31N=71 50/5" 23-50/4" 11-21-18N=39 42-48-33N=81 28-8-6N=14 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-22-2024 Boring Completed07-22-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4979.8 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6497° Longitude: -111.0590° Depth (Ft.)Field TestResults1 2 3 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat noted in upper 6 inches. LEAN CLAY WITH SAND (CL), dark brown, moist,medium stiff SILTY GRAVEL WITH SAND (GM), dark brown to brown,wet, dense to very dense cobbles to boulders, grinding, auger dancing in hole boring terminated due to weather concerns Boring Terminated at 11.5 Feet 4970.4 4968.4 4959.4 Boring Log No. B-7 Water LevelObservationsDepth (Ft.)5 10Graphic LogModel LayerFacilities | Environmental | Geotechnical | Materials 65 12.0 18.2 20.7 13.0 48-27-21 0.5 2.5 11.5 3-6-5N=11 13-24-20N=44 18-38-26N=64 17-22-24N=46 18-19-20N=39 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-24-2024 Boring Completed07-24-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)LL-PL-PI See Exploration PlanLocation: Latitude: 45.6511° Longitude: -111.0581° Depth (Ft.)Field TestResultsElevation: 4970.9 (Ft.) +/- AtterbergLimits 1 2 4971 4969.5 4968 4965.5 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat. LEAN CLAY WITH SAND (CL), trace gravel, black brown,dry to moist, medium stiff, organic. CLAYEY GRAVEL (GC), tan to brown, wet, soft SILTY GRAVEL WITH SAND (GM), black to brown, wet,very dense Boring Terminated at 6.5 Feet Boring Log No. B-8 Water LevelObservationsDepth (Ft.)5 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer50.9 25.5 23.4 1.0 2.5 4.0 6.5 2-4-5N=9 1-1-3N=4 11-19-44N=63 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-25-2024 Boring Completed07-25-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4972.0 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6508° Longitude: -111.0583° Depth (Ft.)Field TestResults1 2 4973.6 4972.1 4970.6 4964.6 4959.6 4954.6 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat. LEAN CLAY WITH SAND (CL), black brown to graybrown, mosit, soft SILTY CLAYEY GRAVEL WITH SAND (GC-GM), black tobrown, wet, medium dense SILTY GRAVEL WITH SAND (GM), black to brown, wet,dense SILTY CLAYEY GRAVEL WITH SAND (GC-GM), brown toblack, wet, dense boulders, slow progress, grinding, auger dancing in hole faster drilling SILTY GRAVEL WITH SAND (GM), brown, wet, dense boulders, slow progress, grinding, auger dancing in hole damage to auger head Auger Refusal at 20 Feet Boring Log No. B-11 Water LevelObservationsDepth (Ft.)5 10 15 20 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer47.6 36.9 15.2 15.3 18.6 22.6 1.0 2.5 4.0 10.0 15.0 20.0 2-4-2N=6 4-16-17N=33 11-12-19N=31 20-23-16N=39 15-19-17N=36 11-17-21N=38 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-24-2024 Boring Completed07-24-2024 Abandonment MethodBoring backfilled with Auger CuttingsSurface capped with concrete Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4974.6 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6505° Longitude: -111.0578° Depth (Ft.)Field TestResults1 2 4976.5 4974.5 4969.5 4967 4957.9 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat noted in upper 6 inches. LEAN CLAY WITH SAND (CL), with organics, low tomedium plasticity, black to brown, mosit to wet, stiff POORLY GRADED GRAVEL WITH SILT AND SAND(GP-GM), fine to coarse grained, low plasticity, blackbrown to brown, wet, dense liduidy silty sand returns, grinding GRAVELLY LEAN CLAY WITH SAND (CL), brown, wet,medium dense to dense ground surface shifting with augering, boulders suspected SILTY GRAVEL WITH SAND (GM), brown, wet, dense cobbles to boulders, slow progress, grinding hit boulder Auger Refusal at 19.1 Feet Boring Log No. B-12 Water LevelObservationsDepth (Ft.)5 10 15 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer36.8 29.1 31.5 21.3 15.2 18.3 27.8 0.5 2.5 7.5 10.0 19.1 5-6-6N=12 3-11-19N=30 11-17-20N=37 14-14-15N=29 14-36-28N=64 17-28-24N=52 50/1" South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-24-2024 Boring Completed07-24-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4977.0 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6499° Longitude: -111.0579° Depth (Ft.)Field TestResults1 2 4969.6 4968.1 4959.1 LEAN CLAY WITH SAND (CL), black to brown, moist,medium stiff SILTY GRAVEL WITH SAND (GM), brown, wet, verydense grinding boring terminated due to weather concerns Boring Terminated at 11.5 Feet Boring Log No. B-14 Water LevelObservationsDepth (Ft.)5 10 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer27.5 11.1 21.4 30.2 17.6 1.0 2.5 11.5 4-3-2N=5 17-28-26N=54 16-26-26N=52 15-27-26N=53 30-30-36N=66 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-25-2024 Boring Completed07-25-2024 Abandonment MethodBoring backfilled with Auger CuttingsSurface capped with concrete Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4970.6 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6511° Longitude: -111.0591° Depth (Ft.)Field TestResults1 2 4972.6 4969.1 4957.1 4947.64947.1 TOPSOIL, dark brown, moist to dry, sandy clay withorganics and root mat LEAN CLAY WITH SAND (CL), organics, black brown togray-brown, dry to wet, soft to medium stiff SILTY GRAVEL WITH SAND (GM), black to brown, wet,very dense, last 9" of sample had reminents of orangeand white-gray pulverized gravel and cobble boulders, slow progress, grinding SILTY CLAYEY GRAVEL WITH SAND (GC-GM), brown totan-brown, wet, denseslow drilling intermittent grinding, significant grinding, smoother by 21.5 feet SANDY LEAN CLAY (CL), brown to orange, wet Boring Terminated at 26.5 Feet Boring Log No. B-15 Water LevelObservationsDepth (Ft.)5 10 15 20 25 Facilities | Environmental | Geotechnical | MaterialsGraphic LogModel Layer24.9 24.9 11.1 16.9 17.2 17.0 27.0 23.8 1.0 4.5 16.5 26.026.5 3-4-3N=7 2-1-2N=3 13-1-20N=21 15-40-43N=83 35-33-30N=63 42-31-34N=65 50/1" 17-21-7N=28 South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Drill RigBK-81 Hammer TypeAutomatic DrillerHazTech Drilling Logged byH.Dorian Boring Started07-25-2024 Boring Completed07-25-2024 Abandonment MethodBoring backfilled with auger cuttings uponcompletion. Advancement Method4 1/4" HSANotes Water Level ObservationsWhile drilling See Exploration and Testing Procedures for a description of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Elevation Reference: Elevations were interpolated from a topographic site plan. Graf Street Apartments Sample TypePercentFinesUnconfinedCompressiveStrength (psf)WaterContent (%)Dry UnitWeight (pcf)Elevation: 4973.6 (Ft.) +/- AtterbergLimits LL-PL-PI See Exploration PlanLocation: Latitude: 45.6508° Longitude: -111.0578° Depth (Ft.)Field TestResults1 2 0 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 90 100 110"A" Line ASTM D4318 CH or O H CL or OL ML or OL MH or OH 20 29 21 59.1 82.4 65.0 CL CH CL 25 28 27 20 29 21 59.1 82.4 65.0 CL CH CL 25 28 27 45 57 48 SANDY LEAN CLAY FAT CLAY with SAND GRAVELLY LEAN CLAY with SAND Atterberg Limit Results "U" LineLiquid Limit LL PL PI Fines USCS DescriptionFinesPlasticity IndexCL - ML 16 4 7 Facilities | Environmental | Geotechnical | Materials 40 - 42 25 - 26.5 1 - 3 B-4 B-5 B-7 Boring ID Depth (Ft) 2110 Overland Ave Ste 124 Billings, MTTerracon Project No. 26235046 South 19th Avenue & West Graf Street | Bozeman, MT Graf Street Apartments 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 U.S. Sieve Numbers 632 10 14 506 2001.5 83/4 1/23/8 30 403 601 140 HydrometerU.S. Sieve Opening in Inches Grain Size Distribution SandGravel Grain Size (mm) coarse fine coarse finemedium Silt or ClayCobbles Percent Coarser by WeightPercent Finer by Weight100 90 80 70 60 50 40 30 20 10 0 ASTM D422 / ASTM C136 / AASHTO T27 16 2044 100 Facilities | Environmental | Geotechnical | Materials 45 57 48 20 29 21 25 28 27 %Clay%Silt 59.1 82.4 65.00.0 0.077 D100 D50D60 D10 %Cobbles LL PL PI Cc CuDescription SANDY LEAN CLAY FAT CLAY with SAND GRAVELLY LEAN CLAY with SAND 1.18 4.75 75 %Gravel 18.3 D30 %Fines 40.9 16.9 16.7 %Sand USCS CL CH CL 2110 Overland Ave Ste 124 Billings, MTTerracon Project No. 26235046 South 19th Avenue & West Graf Street | Bozeman, MT Graf Street Apartments 40 - 42 25 - 26.5 1 - 3 B-4 B-5 B-7 Depth (Ft) 40 - 42 25 - 26.5 1 - 3 B-4 B-5 B-7 Depth (Ft)Boring ID Boring ID -1 0 1 2 3 4 5 6100 1,000 10,000 Pressure (psf) ASTM ASTM D2435 Swell Consolidation Test Axial Strain (%)Facilities | Environmental | Geotechnical | MaterialsLaboratory tests are not valid if separated from original report. Notes: Sample exhibited 0.12 percent compression upon wetting under an applied load of 1,000 psf. 39.273 (pcf) WC (%)Description USCS SANDY LEAN CLAY CL Graf Street Apartments South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 Billings, MT 2110 Overland Ave Ste 124 Boring ID Depth (Ft) 40 - 42B-4 0 200 400 600 800 1,000 1,200 1,400 1,600 1,800 2,000 2,200 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Facilities | Environmental | Geotechnical | Materials 1026 0.0558 3.23 1.96 2.7 2053 5.58 2.85 1.05 100.45 82 39.2 Remarks: Assumed Specific Gravity: Shelby Tube 45 Calculated Void Ratio: Undrained Shear Strength (psf): Height / Diameter Ratio: Calculated Saturation (%): Depth (Ft) 40 - 42 ASTM D2166 Unconfined Compression Test Specimen Test DataSpecimen Failure Mode 25 Axial Strain - % Moisture Content (%): Dry Density (pcf): Diameter (in.): Height (in.): Failure Strain (%): 20Compressive Stress - psfSample type LL PL PI Strain Rate (in/min): Boring ID Description SANDY LEAN CLAY(CL) Unconfined Compressive Strength (psf): B-4 59.1 Fines (%) 2110 Overland Ave Ste 124 Billings, MTTerracon Project No. 26235046 South 19th Avenue & West Graf Street | Bozeman, MT Graf Street Apartments 50 54 58 62 66 70 74 78 82 86 90 94 98 102 106 110 114 118 122 126 130 134 138 142 0 5 10 15 20 25 30 35 40 45 2.60 Moisture-Density Relationship Dry Density (pcf)Water Content (%) ASTM D698-Method A Curves of 100% Saturation for Specific Gravity Equal to: 2.80 2.70 Facilities | Environmental | Geotechnical | Materials Description of Materials Optimum Water Content(%)Maximum Dry Density(pcf)Test Method ASTM D698-Method A 96.8 22.965 48 27 21 Fines(%)PIPLLL GRAVELLY LEAN CLAY with SAND(CL) Fraction> mm size 0.0 B-7 1 - 3 Depth (Ft)Boring ID 2110 Overland Ave Ste 124 Billings, MTTerracon Project No. 26235046 South 19th Avenue & West Graf Street | Bozeman, MT Graf Street Apartments PROJECT:Graf Street Apartments PROJECT NO:26235046 LOCATION:19th and Graf St, Bozeman, MT MATERIAL:Lean Clay with Gravel and Sand SAMPLE SOURCE:B-7 @ 1-3'DATE:8/29/2024 REVIEWED BY:TG COMPACTION(%)94.9%CORRECTED COMPACTION:Recompacted at approx 95% MDD near optimum moisture PENETRATION C B R 0.100 3.1% 0.200 2.6% AFTER SOAK DRY DENSITY 91.8 lbs./cu.ft 91.3 lbs./cu.ft D698 PROCTOR PERCENT MOISTURE 22.9 %29.9 %DRY DENSITY(pcf) 96.8 MOISTURE(%)22.9 SURCHARGE WEIGHT 10 lbs. CBR (CALIFORNIA BEARING RATIO) OF LABORATORY-COMPACTED SOILS (ASTM D1883) AT COMPACTION 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 0 0.1 0.2 0.3 0.4 0.5PENETRATION STRESS (psi)PENETRATION (in) 2110 Overland Avenue, Suite 124, Billings, Montana PHONE: (406) 656-3072 FAX: (406) 656-3578 ISSUED: 9/3/2024 ANALYTICAL SUMMARY REPORT The analyses presented in this report were performed by Energy Laboratories, Inc., 1120 So. 27th Street, Billings, MT 59101, unless otherwise noted. Any exceptions or problems with the analyses are noted in the report package. Any issues encountered during sample receipt are documented in the Work Order Receipt Checklist. The results as reported relate only to the item(s) submitted for testing. This report shall be used or copied only in its entirety. Energy Laboratories, Inc. is not responsible for the consequences arising from the use of a partial report. Energy Laboratories, Inc. verifies the reported results for the analysis has been technically reviewed and approved for release. If you have any questions regarding these test results, please contact your Project Manager. Lab ID Client Sample ID Collect Date Receive Date Matrix Test B24072354-001 B-4 [1-5]Feet 07/23/24 8:00 07/29/24 Soil Anions, Saturated Paste Extract pH, Saturated Paste Saturated Paste Extraction ASA Resistivity, Sat Paste Anions, Saturated Paste Extract Saturation Percentage B24072354-002 B-12 [1-5]Feet 07/24/24 8:00 07/29/24 Soil Same As Above Terracon Consultants Project Name: YTI - New Parcel 26235046 Work Order:B24072354 2110 Overland Ave Ste 124 Billings , MT 59102-6440 August 08, 2024 B5647Quote ID: Energy Laboratories Inc Billings MT received the following 2 samples for Terracon Consultants on 7/29/2024 for analysis. Page 1 of 8 Digitally signed bySonya MallettDate: 2024.08.08 13:05:42 -06:00 LABORATORY ANALYTICAL REPORT Project:YTI - New Parcel 26235046 Client:Terracon Consultants Report Date:08/08/24 Prepared by Billings, MT Branch Collection Date:07/23/24 08:00Lab ID:B24072354-001 Client Sample ID:B-4 [1-5]DateReceived:07/29/24 Matrix:Soil SATURATED PASTE EXTRACT 08/08/24 11:06 / trp1ohm-cm1430Resistivity, Sat. Paste Calculation 08/08/24 10:25 / trp0.1s.u.7.7pH, sat. paste ASA10-3 08/08/24 12:34 / srm0.1%55.3Saturation USDA27a 08/07/24 13:30 / caa1mg/L31Sulfate E300.0 08/08/24 12:45 / srm1mg/kg17Sulfate E300.0 Analyses Result Units Analysis Date / ByRLMethod MCL/ QCLQualifiers Collection Date:07/24/24 08:00Lab ID:B24072354-002 Client Sample ID:B-12 [1-5]DateReceived:07/29/24 Matrix:Soil SATURATED PASTE EXTRACT 08/08/24 11:06 / trp1ohm-cm2200Resistivity, Sat. Paste Calculation 08/08/24 10:25 / trp0.1s.u.7.9pH, sat. paste ASA10-3 08/08/24 12:34 / srm0.1%48.6Saturation USDA27a 08/07/24 14:02 / caa1mg/L27Sulfate E300.0 08/08/24 12:45 / srm1mg/kg13Sulfate E300.0 Analyses Result Units Analysis Date / ByRLMethod MCL/ QCLQualifiers Report Definitions: RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL) Page 2 of 8 Client:Terracon Consultants Work Order:B24072354 QA/QC Summary Report 08/08/24Report Date: Analyte Result %REC RPDLow Limit High Limit RPDLimitRLUnits QualCount Prepared by Billings, MT Branch Method:ASA10-3 Batch: 191994 Lab ID:B24072354-001A DUP 08/08/24 10:25Sample Duplicate Run: MISC-SOIL_240808A pH, sat. paste 100.10 1.37.80 s.u. Lab ID:LCS-2408081025 08/08/24 10:25Laboratory Control Sample Run: MISC-SOIL_240808A pH, sat. paste 101 90 1100.107.10 s.u. Qualifiers: RL - Analyte Reporting Limit ND - Not detected at the Reporting Limit (RL) Page 3 of 8 Client:Terracon Consultants Work Order:B24072354 QA/QC Summary Report 08/08/24Report Date: Analyte Result %REC RPDLow Limit High Limit RPDLimitRLUnits QualCount Prepared by Billings, MT Branch Method:Calculation Batch: 191994 Lab ID:B24072354-001ADUP 08/08/24 11:06Sample Duplicate Run: MISC-SOIL_240808A Resistivity, Sat. Paste 70 130 301.0 0.01430 ohm-cm Lab ID:LCS-2408081106 08/08/24 11:06Laboratory Control Sample Run: MISC-SOIL_240808A Resistivity, Sat. Paste 113 70 1301.0149 ohm-cm Qualifiers: RL - Analyte Reporting Limit ND - Not detected at the Reporting Limit (RL) Page 4 of 8 Client:Terracon Consultants Work Order:B24072354 QA/QC Summary Report 08/08/24Report Date: Analyte Result %REC RPDLow Limit High Limit RPDLimitRLUnits QualCount Prepared by Billings, MT Branch Method:E300.0 Batch: 191994 Lab ID:MB-191994 08/07/24 12:57Method Blank Run: IC METROHM 1_240807A Sulfate 0.1NDmg/L Lab ID:LCS-191994 08/07/24 13:13Laboratory Control Sample Run: IC METROHM 1_240807A Sulfate 121 70 1302.92420mg/L Lab ID:B24072354-001ADUP 08/07/24 13:46Sample Duplicate Run: IC METROHM 1_240807A Sulfate 301.0 1.831.9 mg/L Lab ID:B24080169-002AMS 08/07/24 16:58Sample Matrix Spike Run: IC METROHM 1_240807A Sulfate 110 70 1303.12480mg/L Qualifiers: RL - Analyte Reporting Limit ND - Not detected at the Reporting Limit (RL) Page 5 of 8 Client:Terracon Consultants Work Order:B24072354 QA/QC Summary Report 08/08/24Report Date: Analyte Result %REC RPDLow Limit High Limit RPDLimitRLUnits QualCount Prepared by Billings, MT Branch Method:USDA27a Batch: 191994 Lab ID:B24072354-001ADUP 08/08/24 12:34Sample Duplicate Run: MISC-SOIL_240808B Saturation 200.10 0.755.7 % Lab ID:LCS-2408081234 08/08/24 12:34Laboratory Control Sample Run: MISC-SOIL_240808B Saturation 99 80 1200.1036.4 % Qualifiers: RL - Analyte Reporting Limit ND - Not detected at the Reporting Limit (RL) Page 6 of 8 Shipping container/cooler in good condition? Custody seals intact on all shipping container(s)/cooler(s)? Custody seals intact on all sample bottles? Chain of custody present? Chain of custody signed when relinquished and received? Chain of custody agrees with sample labels? Samples in proper container/bottle? Sample containers intact? Sufficient sample volume for indicated test? All samples received within holding time? (Exclude analyses that are considered field parameters such as pH, DO, Res Cl, Sulfite, Ferrous Iron, etc.) Container/Temp Blank temperature: Containers requiring zero headspace have no headspace or bubble that is <6mm (1/4"). Water - pH acceptable upon receipt? Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No No No No No No No No No No No No Not Present Not Present Not Present No VOA vials submitted Not Applicable 7/29/2024Crystal M. Jones Hand Deliver DNH Date Received: Received by: Login completed by: Carrier name: lleprowse 8/5/2024 Reviewed by: Reviewed Date: Contact and Corrective Action Comments: None Temp Blank received in all shipping container(s)/cooler(s)?Yes No Not Applicable Lab measurement of analytes considered field parameters that require analysis within 15 minutes of sampling such as pH, Dissolved Oxygen and Residual Chlorine, are qualified as being analyzed outside of recommended holding time. Solid/soil samples are reported on a wet weight basis (as received) unless specifically indicated. If moisture corrected, data units are typically noted as dry. For agricultural and mining soil parameters/characteristics, all samples are dried and ground prior to sample analysis. The reference date for Radon analysis is the sample collection date. The reference date for all other Radiochemical analyses is the analysis date. Radiochemical precision results represent a 2-sigma Total Measurement Uncertainty. For methods that require zero headspace or require preservation check at the time of analysis due to potential interference, the pH is verified at analysis. Nonconforming sample pH is documented as part of the analysis and included in the sample analysis comments. Trip Blanks and/or Blind Duplicate samples are assigned the earliest collection time for the associated requested analysis in order to evaluate the holding time unless specifically indicated. Standard Reporting Procedures: Work Order Receipt Checklist Terracon Consultants B24072354 Page 7 of 8 Page 8 of 8 Supporting Information Contents: General Notes Unified Soil Classification System Note: All attachments are one page unless noted above. Grab Sample Shelby Tube Split Spoon Facilities | Environmental | Geotechnical | Materials > 8,000 4,000 to 8,000 2,000 to 4,000 1,000 to 2,000 500 to 1,000 less than 500 Unconfined CompressiveStrengthQu (psf) Graf Street Apartments South 19th Avenue & West Graf Street | Bozeman, MT Terracon Project No. 26235046 2110 Overland Ave Ste 124 Billings, MT N (HP) (T) (DCP) UC (PID) (OVA) Standard Penetration TestResistance (Blows/Ft.) Hand Penetrometer Torvane Dynamic Cone Penetrometer Unconfined CompressiveStrength Photo-Ionization Detector Organic Vapor Analyzer Water Level After aSpecified Period of Time Water Level Aftera Specified Period of Time Cave InEncountered Water Level Field Tests Water InitiallyEncountered Sampling Water levels indicated on the soil boring logs are the levels measured in the borehole at the times indicated. Groundwater level variations will occur over time. In low permeability soils, accurate determination of groundwater levels is not possible with short term water level observations. General Notes Location And Elevation Notes Exploration point locations as shown on the Exploration Plan and as noted on the soil boring logs in the form of Latitude and Longitude are approximate. See Exploration and Testing Procedures in the report for the methods used to locate the exploration points for this project. Surface elevation data annotated with +/- indicates that no actual topographical survey was conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic maps of the area. Soil classification as noted on the soil boring logs is based Unified Soil Classification System. Where sufficient laboratory data exist to classify the soils consistent with ASTM D2487 "Classification of Soils for Engineering Purposes" this procedure is used. ASTM D2488 "Description and Identification of Soils (Visual-Manual Procedure)" is also used to classify the soils, particularly where insufficient laboratory data exist to classify the soils in accordance with ASTM D2487. In addition to USCS classification, coarse grained soils are classified on the basis of their in-place relative density, and fine-grained soils are classified on the basis of their consistency. See "Strength Terms" table below for details. The ASTM standards noted above are for reference to methodology in general. In some cases, variations to methods are applied as a result of local practice or professional judgment. Exploration/field results and/or laboratory test data contained within this document are intended for application to the project as described in this document. Use of such exploration/field results and/or laboratory test data should not be used independently of this document. Relevance of Exploration and Laboratory Test Results Descriptive Soil Classification > 30 15 - 30 8 - 15 4 - 8 2 - 4 Hard > 50 Very Stiff Stiff Medium Stiff Soft Very Soft 30 - 50 10 - 29 4 - 9 0 - 3Very Loose Loose Medium Dense Dense Very Dense Relative Density of Coarse-Grained Soils (More than 50% retained on No. 200 sieve.)Density determined by Standard Penetration Resistance Consistency of Fine-Grained Soils (50% or more passing the No. 200 sieve.)Consistency determined by laboratory shear strength testing, field visual-manualprocedures or standard penetration resistance 0 - 1 Relative Density ConsistencyStandard Penetration orN-Value(Blows/Ft.) Standard Penetration orN-Value(Blows/Ft.) Strength Terms Geotechnical Engineering Report Graf Street Apartments | Bozeman, Montana September 12, 2024 | Terracon Project No. 26235046 Facilities | Environmental | Geotechnical | Materials Unified Soil Classification System Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A Soil Classification Group Symbol Group Name B Coarse-Grained Soils: More than 50% retained on No. 200 sieve Gravels: More than 50% of coarse fraction retained on No. 4 sieve Clean Gravels: Less than 5% fines C Cu≥4 and 1≤Cc≤3 E GW Well-graded gravel F Cu<4 and/or [Cc<1 or Cc>3.0] E GP Poorly graded gravel F Gravels with Fines: More than 12% fines C Fines classify as ML or MH GM Silty gravel F, G, H Fines classify as CL or CH GC Clayey gravel F, G, H Sands: 50% or more of coarse fraction passes No. 4 sieve Clean Sands: Less than 5% fines D Cu≥6 and 1≤Cc≤3 E SW Well-graded sand I Cu<6 and/or [Cc<1 or Cc>3.0] E SP Poorly graded sand I Sands with Fines: More than 12% fines D Fines classify as ML or MH SM Silty sand G, H, I Fines classify as CL or CH SC Clayey sand G, H, I Fine-Grained Soils: 50% or more passes the No. 200 sieve Silts and Clays: Liquid limit less than 50 Inorganic: PI > 7 and plots above “A” line J CL Lean clay K, L, M PI < 4 or plots below “A” line J ML Silt K, L, M Organic: 𝐿𝐿 𝑛𝑣𝑑𝑛 𝑑𝑟𝑖𝑑𝑑 𝐿𝐿 𝑛𝑛𝑡 𝑑𝑟𝑖𝑑𝑑<0.75 OL Organic clay K, L, M, N Organic silt K, L, M, O Silts and Clays: Liquid limit 50 or more Inorganic: PI plots on or above “A” line CH Fat clay K, L, M PI plots below “A” line MH Elastic silt K, L, M Organic: 𝐿𝐿 𝑛𝑣𝑑𝑛 𝑑𝑟𝑖𝑑𝑑 𝐿𝐿 𝑛𝑛𝑡 𝑑𝑟𝑖𝑑𝑑<0.75 OH Organic clay K, L, M, P Organic silt K, L, M, Q Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-inch (75-mm) sieve. B If field sample contained cobbles or boulders, or both, add “with cobbles or boulders, or both” to group name. C Gravels with 5 to 12% fines require dual symbols: GW-GM well- graded gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay. E Cu = D60/D10 Cc = F If soil contains ≥ 15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. H If fines are organic, add “with organic fines” to group name. I If soil contains ≥ 15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant. L If soil contains ≥ 30% plus No. 200 predominantly sand, add “sandy” to group name. M If soil contains ≥ 30% plus No. 200, predominantly gravel, add “gravelly” to group name. N PI ≥ 4 and plots on or above “A” line. O PI < 4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line. 6010 2 30 DxD )(D Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 7 APPENDIX C: DETENTION SYSTEM SIZING CALCULATIONS 1S DevCo Graf Routing Diagram for TB-Graf St - EX Prepared by Kimley-Horn & Associates, Printed 3/31/2025 HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Subcat Reach Pond Link Type II 24-hr First 0.5 Rainfall=0.50"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Events for Subcatchment 1S: DevCo Graf Event Rainfall (inches) Runoff (cfs) Volume (acre-feet) Depth (inches) 2yr 1.18 0.11 0.034 0.04 5yr 1.49 0.71 0.091 0.12 10yr 1.70 1.40 0.143 0.19 25yr 1.96 2.53 0.219 0.29 50yr 2.15 3.47 0.282 0.37 100yr 2.34 4.51 0.350 0.46 First 0.5 0.50 0.00 0.000 0.00 TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 2HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Rainfall Events Listing Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 2yr Type II 24-hr Default 24.00 1 1.18 2 2 5yr Type II 24-hr Default 24.00 1 1.49 2 3 10yr Type II 24-hr Default 24.00 1 1.70 2 4 25yr Type II 24-hr Default 24.00 1 1.96 2 5 50yr Type II 24-hr Default 24.00 1 2.15 2 6 100yr Type II 24-hr Default 24.00 1 2.34 2 7 First 0.5 Type II 24-hr Default 24.00 1 0.50 2 TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 3HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 9.190 74 Pasture/grassland/range, Good, HSG C (1S) 9.190 74 TOTAL AREA TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 4HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.000 HSG A 0.000 HSG B 9.190 HSG C 1S 0.000 HSG D 0.000 Other 9.190 TOTAL AREA TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 5HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.000 0.000 9.190 0.000 0.000 9.190 Pasture/grassland/range, Good 1S 0.000 0.000 9.190 0.000 0.000 9.190 TOTAL AREA Type II 24-hr 2yr Rainfall=1.18"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 6HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 0.00% Impervious Runoff Depth>0.04"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=74 Runoff=0.11 cfs 0.034 af Total Runoff Area = 9.190 ac Runoff Volume = 0.034 af Average Runoff Depth = 0.04" 100.00% Pervious = 9.190 ac 0.00% Impervious = 0.000 ac Type II 24-hr 2yr Rainfall=1.18"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 7HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff =0.11 cfs @ 12.48 hrs, Volume=0.034 af, Depth> 0.04" Routed to nonexistent node 3P Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 2yr Rainfall=1.18" Area (ac) CN Description 9.190 74 Pasture/grassland/range, Good, HSG C 9.190 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 20.0 Direct Entry, Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 201918171615141312111098765Flow(cfs)0.115 0.11 0.105 0.1 0.095 0.09 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type II 24-hr 2yr Rainfall=1.18" Runoff Area=9.190 ac Runoff Volume=0.034 af Runoff Depth>0.04" Tc=20.0 min CN=74 0.11 cfs Type II 24-hr 2yr Rainfall=1.18"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 8HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 5.00 0.07 0.00 0.00 5.25 0.08 0.00 0.00 5.50 0.08 0.00 0.00 5.75 0.09 0.00 0.00 6.00 0.09 0.00 0.00 6.25 0.10 0.00 0.00 6.50 0.11 0.00 0.00 6.75 0.11 0.00 0.00 7.00 0.12 0.00 0.00 7.25 0.12 0.00 0.00 7.50 0.13 0.00 0.00 7.75 0.14 0.00 0.00 8.00 0.14 0.00 0.00 8.25 0.15 0.00 0.00 8.50 0.16 0.00 0.00 8.75 0.16 0.00 0.00 9.00 0.17 0.00 0.00 9.25 0.18 0.00 0.00 9.50 0.19 0.00 0.00 9.75 0.20 0.00 0.00 10.00 0.21 0.00 0.00 10.25 0.23 0.00 0.00 10.50 0.24 0.00 0.00 10.75 0.26 0.00 0.00 11.00 0.28 0.00 0.00 11.25 0.30 0.00 0.00 11.50 0.33 0.00 0.00 11.75 0.46 0.00 0.00 12.00 0.78 0.00 0.00 12.25 0.83 0.00 0.09 12.50 0.87 0.01 0.1112.75 0.89 0.01 0.09 13.00 0.91 0.01 0.08 13.25 0.93 0.01 0.08 13.50 0.94 0.02 0.07 13.75 0.96 0.02 0.07 14.00 0.97 0.02 0.06 14.25 0.98 0.02 0.06 14.50 0.99 0.02 0.05 14.75 1.00 0.02 0.05 15.00 1.01 0.02 0.05 15.25 1.02 0.03 0.05 15.50 1.02 0.03 0.05 15.75 1.03 0.03 0.05 16.00 1.04 0.03 0.04 16.25 1.05 0.03 0.04 16.50 1.05 0.03 0.04 16.75 1.06 0.03 0.04 17.00 1.06 0.03 0.04 17.25 1.07 0.03 0.04 17.50 1.08 0.04 0.04 17.75 1.08 0.04 0.04 18.00 1.09 0.04 0.04 18.25 1.09 0.04 0.04 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 18.50 1.10 0.04 0.04 18.75 1.10 0.04 0.04 19.00 1.11 0.04 0.03 19.25 1.11 0.04 0.03 19.50 1.12 0.04 0.03 19.75 1.12 0.04 0.03 20.00 1.12 0.04 0.03 Type II 24-hr 5yr Rainfall=1.49"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 9HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 0.00% Impervious Runoff Depth>0.12"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=74 Runoff=0.71 cfs 0.091 af Total Runoff Area = 9.190 ac Runoff Volume = 0.091 af Average Runoff Depth = 0.12" 100.00% Pervious = 9.190 ac 0.00% Impervious = 0.000 ac Type II 24-hr 5yr Rainfall=1.49"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 10HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff =0.71 cfs @ 12.21 hrs, Volume=0.091 af, Depth> 0.12" Routed to nonexistent node 3P Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 5yr Rainfall=1.49" Area (ac) CN Description 9.190 74 Pasture/grassland/range, Good, HSG C 9.190 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 20.0 Direct Entry, Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 201918171615141312111098765Flow(cfs)0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type II 24-hr 5yr Rainfall=1.49" Runoff Area=9.190 ac Runoff Volume=0.091 af Runoff Depth>0.12" Tc=20.0 min CN=74 0.71 cfs Type II 24-hr 5yr Rainfall=1.49"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 11HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 5.00 0.09 0.00 0.00 5.25 0.10 0.00 0.00 5.50 0.11 0.00 0.00 5.75 0.11 0.00 0.00 6.00 0.12 0.00 0.00 6.25 0.13 0.00 0.00 6.50 0.13 0.00 0.00 6.75 0.14 0.00 0.00 7.00 0.15 0.00 0.00 7.25 0.16 0.00 0.00 7.50 0.16 0.00 0.00 7.75 0.17 0.00 0.00 8.00 0.18 0.00 0.00 8.25 0.19 0.00 0.00 8.50 0.20 0.00 0.00 8.75 0.21 0.00 0.00 9.00 0.22 0.00 0.00 9.25 0.23 0.00 0.00 9.50 0.24 0.00 0.00 9.75 0.26 0.00 0.00 10.00 0.27 0.00 0.00 10.25 0.29 0.00 0.00 10.50 0.30 0.00 0.00 10.75 0.33 0.00 0.00 11.00 0.35 0.00 0.00 11.25 0.38 0.00 0.00 11.50 0.42 0.00 0.00 11.75 0.58 0.00 0.00 12.00 0.99 0.02 0.12 12.25 1.05 0.03 0.6812.50 1.10 0.04 0.40 12.75 1.13 0.05 0.27 13.00 1.15 0.05 0.22 13.25 1.17 0.06 0.19 13.50 1.19 0.06 0.17 13.75 1.21 0.06 0.15 14.00 1.22 0.07 0.14 14.25 1.24 0.07 0.13 14.50 1.25 0.07 0.12 14.75 1.26 0.08 0.12 15.00 1.27 0.08 0.11 15.25 1.28 0.08 0.11 15.50 1.29 0.08 0.10 15.75 1.30 0.09 0.10 16.00 1.31 0.09 0.09 16.25 1.32 0.09 0.09 16.50 1.33 0.09 0.09 16.75 1.34 0.10 0.08 17.00 1.34 0.10 0.08 17.25 1.35 0.10 0.08 17.50 1.36 0.10 0.08 17.75 1.37 0.11 0.08 18.00 1.37 0.11 0.08 18.25 1.38 0.11 0.07 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 18.50 1.39 0.11 0.07 18.75 1.39 0.11 0.07 19.00 1.40 0.11 0.07 19.25 1.40 0.12 0.07 19.50 1.41 0.12 0.06 19.75 1.41 0.12 0.06 20.00 1.42 0.12 0.06 Type II 24-hr 10yr Rainfall=1.70"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 12HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 0.00% Impervious Runoff Depth>0.19"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=74 Runoff=1.40 cfs 0.143 af Total Runoff Area = 9.190 ac Runoff Volume = 0.143 af Average Runoff Depth = 0.19" 100.00% Pervious = 9.190 ac 0.00% Impervious = 0.000 ac Type II 24-hr 10yr Rainfall=1.70"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 13HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff =1.40 cfs @ 12.18 hrs, Volume=0.143 af, Depth> 0.19" Routed to nonexistent node 3P Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10yr Rainfall=1.70" Area (ac) CN Description 9.190 74 Pasture/grassland/range, Good, HSG C 9.190 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 20.0 Direct Entry, Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 201918171615141312111098765Flow(cfs)1 0 Type II 24-hr 10yr Rainfall=1.70" Runoff Area=9.190 ac Runoff Volume=0.143 af Runoff Depth>0.19" Tc=20.0 min CN=74 1.40 cfs Type II 24-hr 10yr Rainfall=1.70"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 14HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 5.00 0.11 0.00 0.00 5.25 0.11 0.00 0.00 5.50 0.12 0.00 0.00 5.75 0.13 0.00 0.00 6.00 0.14 0.00 0.00 6.25 0.14 0.00 0.00 6.50 0.15 0.00 0.00 6.75 0.16 0.00 0.00 7.00 0.17 0.00 0.00 7.25 0.18 0.00 0.00 7.50 0.19 0.00 0.00 7.75 0.19 0.00 0.00 8.00 0.20 0.00 0.00 8.25 0.21 0.00 0.00 8.50 0.22 0.00 0.00 8.75 0.24 0.00 0.00 9.00 0.25 0.00 0.00 9.25 0.26 0.00 0.00 9.50 0.28 0.00 0.00 9.75 0.29 0.00 0.00 10.00 0.31 0.00 0.00 10.25 0.33 0.00 0.00 10.50 0.35 0.00 0.00 10.75 0.37 0.00 0.00 11.00 0.40 0.00 0.00 11.25 0.44 0.00 0.00 11.50 0.48 0.00 0.00 11.75 0.66 0.00 0.00 12.00 1.13 0.05 0.37 12.25 1.20 0.06 1.2812.50 1.25 0.07 0.66 12.75 1.28 0.08 0.42 13.00 1.31 0.09 0.33 13.25 1.34 0.10 0.28 13.50 1.36 0.10 0.25 13.75 1.38 0.11 0.22 14.00 1.39 0.11 0.20 14.25 1.41 0.12 0.18 14.50 1.42 0.12 0.17 14.75 1.44 0.13 0.17 15.00 1.45 0.13 0.16 15.25 1.46 0.14 0.15 15.50 1.47 0.14 0.15 15.75 1.49 0.14 0.14 16.00 1.50 0.15 0.13 16.25 1.51 0.15 0.12 16.50 1.52 0.15 0.12 16.75 1.52 0.16 0.12 17.00 1.53 0.16 0.11 17.25 1.54 0.16 0.11 17.50 1.55 0.16 0.11 17.75 1.56 0.17 0.11 18.00 1.57 0.17 0.10 18.25 1.57 0.17 0.10 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 18.50 1.58 0.18 0.10 18.75 1.59 0.18 0.10 19.00 1.59 0.18 0.09 19.25 1.60 0.18 0.09 19.50 1.61 0.19 0.09 19.75 1.61 0.19 0.08 20.00 1.62 0.19 0.08 Type II 24-hr 25yr Rainfall=1.96"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 15HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 0.00% Impervious Runoff Depth>0.29"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=74 Runoff=2.53 cfs 0.219 af Total Runoff Area = 9.190 ac Runoff Volume = 0.219 af Average Runoff Depth = 0.29" 100.00% Pervious = 9.190 ac 0.00% Impervious = 0.000 ac Type II 24-hr 25yr Rainfall=1.96"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 16HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff =2.53 cfs @ 12.17 hrs, Volume=0.219 af, Depth> 0.29" Routed to nonexistent node 3P Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25yr Rainfall=1.96" Area (ac) CN Description 9.190 74 Pasture/grassland/range, Good, HSG C 9.190 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 20.0 Direct Entry, Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 201918171615141312111098765Flow(cfs)2 1 0 Type II 24-hr 25yr Rainfall=1.96" Runoff Area=9.190 ac Runoff Volume=0.219 af Runoff Depth>0.29" Tc=20.0 min CN=74 2.53 cfs Type II 24-hr 25yr Rainfall=1.96"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 17HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 5.00 0.12 0.00 0.00 5.25 0.13 0.00 0.00 5.50 0.14 0.00 0.00 5.75 0.15 0.00 0.00 6.00 0.16 0.00 0.00 6.25 0.17 0.00 0.00 6.50 0.17 0.00 0.00 6.75 0.18 0.00 0.00 7.00 0.19 0.00 0.00 7.25 0.20 0.00 0.00 7.50 0.21 0.00 0.00 7.75 0.22 0.00 0.00 8.00 0.24 0.00 0.00 8.25 0.25 0.00 0.00 8.50 0.26 0.00 0.00 8.75 0.27 0.00 0.00 9.00 0.29 0.00 0.00 9.25 0.30 0.00 0.00 9.50 0.32 0.00 0.00 9.75 0.34 0.00 0.00 10.00 0.35 0.00 0.00 10.25 0.38 0.00 0.00 10.50 0.40 0.00 0.00 10.75 0.43 0.00 0.00 11.00 0.46 0.00 0.00 11.25 0.50 0.00 0.00 11.50 0.55 0.00 0.00 11.75 0.76 0.00 0.00 12.00 1.30 0.09 0.93 12.25 1.38 0.11 2.1912.50 1.44 0.13 1.02 12.75 1.48 0.14 0.62 13.00 1.51 0.15 0.47 13.25 1.54 0.16 0.40 13.50 1.57 0.17 0.35 13.75 1.59 0.18 0.31 14.00 1.61 0.19 0.28 14.25 1.62 0.19 0.26 14.50 1.64 0.20 0.24 14.75 1.66 0.20 0.23 15.00 1.67 0.21 0.22 15.25 1.69 0.22 0.21 15.50 1.70 0.22 0.20 15.75 1.71 0.23 0.19 16.00 1.72 0.23 0.18 16.25 1.74 0.23 0.17 16.50 1.75 0.24 0.16 16.75 1.76 0.24 0.16 17.00 1.77 0.25 0.16 17.25 1.78 0.25 0.15 17.50 1.79 0.26 0.15 17.75 1.80 0.26 0.15 18.00 1.81 0.26 0.14 18.25 1.81 0.27 0.14 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 18.50 1.82 0.27 0.13 18.75 1.83 0.27 0.13 19.00 1.84 0.28 0.13 19.25 1.85 0.28 0.12 19.50 1.85 0.28 0.12 19.75 1.86 0.29 0.11 20.00 1.87 0.29 0.11 Type II 24-hr 50yr Rainfall=2.15"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 18HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 0.00% Impervious Runoff Depth>0.37"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=74 Runoff=3.47 cfs 0.282 af Total Runoff Area = 9.190 ac Runoff Volume = 0.282 af Average Runoff Depth = 0.37" 100.00% Pervious = 9.190 ac 0.00% Impervious = 0.000 ac Type II 24-hr 50yr Rainfall=2.15"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 19HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff =3.47 cfs @ 12.16 hrs, Volume=0.282 af, Depth> 0.37" Routed to nonexistent node 3P Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 50yr Rainfall=2.15" Area (ac) CN Description 9.190 74 Pasture/grassland/range, Good, HSG C 9.190 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 20.0 Direct Entry, Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 201918171615141312111098765Flow(cfs)3 2 1 0 Type II 24-hr 50yr Rainfall=2.15" Runoff Area=9.190 ac Runoff Volume=0.282 af Runoff Depth>0.37" Tc=20.0 min CN=74 3.47 cfs Type II 24-hr 50yr Rainfall=2.15"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 20HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 5.00 0.14 0.00 0.00 5.25 0.14 0.00 0.00 5.50 0.15 0.00 0.00 5.75 0.16 0.00 0.00 6.00 0.17 0.00 0.00 6.25 0.18 0.00 0.00 6.50 0.19 0.00 0.00 6.75 0.20 0.00 0.00 7.00 0.21 0.00 0.00 7.25 0.22 0.00 0.00 7.50 0.23 0.00 0.00 7.75 0.25 0.00 0.00 8.00 0.26 0.00 0.00 8.25 0.27 0.00 0.00 8.50 0.28 0.00 0.00 8.75 0.30 0.00 0.00 9.00 0.32 0.00 0.00 9.25 0.33 0.00 0.00 9.50 0.35 0.00 0.00 9.75 0.37 0.00 0.00 10.00 0.39 0.00 0.00 10.25 0.41 0.00 0.00 10.50 0.44 0.00 0.00 10.75 0.47 0.00 0.00 11.00 0.51 0.00 0.00 11.25 0.55 0.00 0.00 11.50 0.61 0.00 0.00 11.75 0.83 0.00 0.01 12.00 1.43 0.12 1.48 12.25 1.52 0.15 2.9312.50 1.58 0.18 1.31 12.75 1.62 0.19 0.78 13.00 1.66 0.20 0.59 13.25 1.69 0.22 0.49 13.50 1.72 0.23 0.43 13.75 1.74 0.24 0.39 14.00 1.76 0.25 0.35 14.25 1.78 0.25 0.31 14.50 1.80 0.26 0.30 14.75 1.82 0.27 0.28 15.00 1.84 0.28 0.27 15.25 1.85 0.28 0.26 15.50 1.87 0.29 0.25 15.75 1.88 0.30 0.23 16.00 1.89 0.30 0.22 16.25 1.90 0.31 0.21 16.50 1.92 0.31 0.20 16.75 1.93 0.32 0.20 17.00 1.94 0.32 0.19 17.25 1.95 0.33 0.19 17.50 1.96 0.33 0.18 17.75 1.97 0.34 0.18 18.00 1.98 0.34 0.17 18.25 1.99 0.35 0.17 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 18.50 2.00 0.35 0.16 18.75 2.01 0.35 0.16 19.00 2.02 0.36 0.15 19.25 2.02 0.36 0.15 19.50 2.03 0.36 0.14 19.75 2.04 0.37 0.14 20.00 2.05 0.37 0.13 Type II 24-hr 100yr Rainfall=2.34"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 21HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 0.00% Impervious Runoff Depth>0.46"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=74 Runoff=4.51 cfs 0.350 af Total Runoff Area = 9.190 ac Runoff Volume = 0.350 af Average Runoff Depth = 0.46" 100.00% Pervious = 9.190 ac 0.00% Impervious = 0.000 ac Type II 24-hr 100yr Rainfall=2.34"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 22HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff =4.51 cfs @ 12.16 hrs, Volume=0.350 af, Depth> 0.46" Routed to nonexistent node 3P Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100yr Rainfall=2.34" Area (ac) CN Description 9.190 74 Pasture/grassland/range, Good, HSG C 9.190 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 20.0 Direct Entry, Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 201918171615141312111098765Flow(cfs)5 4 3 2 1 0 Type II 24-hr 100yr Rainfall=2.34" Runoff Area=9.190 ac Runoff Volume=0.350 af Runoff Depth>0.46" Tc=20.0 min CN=74 4.51 cfs Type II 24-hr 100yr Rainfall=2.34"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 23HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 5.00 0.15 0.00 0.00 5.25 0.16 0.00 0.00 5.50 0.17 0.00 0.00 5.75 0.18 0.00 0.00 6.00 0.19 0.00 0.00 6.25 0.20 0.00 0.00 6.50 0.21 0.00 0.00 6.75 0.22 0.00 0.00 7.00 0.23 0.00 0.00 7.25 0.24 0.00 0.00 7.50 0.26 0.00 0.00 7.75 0.27 0.00 0.00 8.00 0.28 0.00 0.00 8.25 0.29 0.00 0.00 8.50 0.31 0.00 0.00 8.75 0.33 0.00 0.00 9.00 0.34 0.00 0.00 9.25 0.36 0.00 0.00 9.50 0.38 0.00 0.00 9.75 0.40 0.00 0.00 10.00 0.42 0.00 0.00 10.25 0.45 0.00 0.00 10.50 0.48 0.00 0.00 10.75 0.51 0.00 0.00 11.00 0.55 0.00 0.00 11.25 0.60 0.00 0.00 11.50 0.66 0.00 0.00 11.75 0.91 0.01 0.03 12.00 1.55 0.17 2.14 12.25 1.65 0.20 3.7312.50 1.72 0.23 1.62 12.75 1.77 0.25 0.95 13.00 1.81 0.26 0.70 13.25 1.84 0.28 0.59 13.50 1.87 0.29 0.52 13.75 1.90 0.30 0.46 14.00 1.92 0.31 0.41 14.25 1.94 0.32 0.37 14.50 1.96 0.33 0.35 14.75 1.98 0.34 0.34 15.00 2.00 0.35 0.32 15.25 2.01 0.36 0.31 15.50 2.03 0.36 0.29 15.75 2.05 0.37 0.28 16.00 2.06 0.38 0.26 16.25 2.07 0.38 0.24 16.50 2.09 0.39 0.24 16.75 2.10 0.40 0.23 17.00 2.11 0.40 0.22 17.25 2.12 0.41 0.22 17.50 2.13 0.41 0.21 17.75 2.14 0.42 0.21 18.00 2.16 0.42 0.20 18.25 2.17 0.43 0.20 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 18.50 2.18 0.44 0.19 18.75 2.19 0.44 0.18 19.00 2.19 0.44 0.18 19.25 2.20 0.45 0.17 19.50 2.21 0.45 0.17 19.75 2.22 0.46 0.16 20.00 2.23 0.46 0.15 Type II 24-hr First 0.5 Rainfall=0.50"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 24HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 0.00% Impervious Runoff Depth=0.00"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=74 Runoff=0.00 cfs 0.000 af Total Runoff Area = 9.190 ac Runoff Volume = 0.000 af Average Runoff Depth = 0.00" 100.00% Pervious = 9.190 ac 0.00% Impervious = 0.000 ac Type II 24-hr First 0.5 Rainfall=0.50"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 25HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff =0.00 cfs @ 5.00 hrs, Volume=0.000 af, Depth= 0.00" Routed to nonexistent node 3P Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr First 0.5 Rainfall=0.50" Area (ac) CN Description 9.190 74 Pasture/grassland/range, Good, HSG C 9.190 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 20.0 Direct Entry, Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 201918171615141312111098765Flow(cfs)1 0 Type II 24-hr First 0.5 Rainfall=0.50" Runoff Area=9.190 ac Runoff Volume=0.000 af Runoff Depth=0.00" Tc=20.0 min CN=74 0.00 cfs Type II 24-hr First 0.5 Rainfall=0.50"TB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates Page 26HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 5.00 0.03 0.00 0.005.25 0.03 0.00 0.00 5.50 0.04 0.00 0.00 5.75 0.04 0.00 0.00 6.00 0.04 0.00 0.00 6.25 0.04 0.00 0.00 6.50 0.04 0.00 0.00 6.75 0.05 0.00 0.00 7.00 0.05 0.00 0.00 7.25 0.05 0.00 0.00 7.50 0.05 0.00 0.00 7.75 0.06 0.00 0.00 8.00 0.06 0.00 0.00 8.25 0.06 0.00 0.00 8.50 0.07 0.00 0.00 8.75 0.07 0.00 0.00 9.00 0.07 0.00 0.00 9.25 0.08 0.00 0.00 9.50 0.08 0.00 0.00 9.75 0.09 0.00 0.00 10.00 0.09 0.00 0.00 10.25 0.10 0.00 0.00 10.50 0.10 0.00 0.00 10.75 0.11 0.00 0.00 11.00 0.12 0.00 0.00 11.25 0.13 0.00 0.00 11.50 0.14 0.00 0.00 11.75 0.19 0.00 0.00 12.00 0.33 0.00 0.00 12.25 0.35 0.00 0.00 12.50 0.37 0.00 0.00 12.75 0.38 0.00 0.00 13.00 0.39 0.00 0.00 13.25 0.39 0.00 0.00 13.50 0.40 0.00 0.00 13.75 0.41 0.00 0.00 14.00 0.41 0.00 0.00 14.25 0.41 0.00 0.00 14.50 0.42 0.00 0.00 14.75 0.42 0.00 0.00 15.00 0.43 0.00 0.00 15.25 0.43 0.00 0.00 15.50 0.43 0.00 0.00 15.75 0.44 0.00 0.00 16.00 0.44 0.00 0.00 16.25 0.44 0.00 0.00 16.50 0.45 0.00 0.00 16.75 0.45 0.00 0.00 17.00 0.45 0.00 0.00 17.25 0.45 0.00 0.00 17.50 0.46 0.00 0.00 17.75 0.46 0.00 0.00 18.00 0.46 0.00 0.00 18.25 0.46 0.00 0.00 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 18.50 0.46 0.00 0.00 18.75 0.47 0.00 0.00 19.00 0.47 0.00 0.00 19.25 0.47 0.00 0.00 19.50 0.47 0.00 0.00 19.75 0.47 0.00 0.00 20.00 0.48 0.00 0.00 Table of ContentsTB-Graf St - EX Printed 3/31/2025Prepared by Kimley-Horn & Associates HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC TABLE OF CONTENTS Project Reports 1 Routing Diagram 2 Rainfall Events Listing 3 Area Listing (all nodes) 4 Soil Listing (all nodes) 5 Ground Covers (all nodes) 2yr Event 6 Node Listing 7 Subcat 1S: DevCo Graf 5yr Event 9 Node Listing 10 Subcat 1S: DevCo Graf 10yr Event 12 Node Listing 13 Subcat 1S: DevCo Graf 25yr Event 15 Node Listing 16 Subcat 1S: DevCo Graf 50yr Event 18 Node Listing 19 Subcat 1S: DevCo Graf 100yr Event 21 Node Listing 22 Subcat 1S: DevCo Graf First 0.5 Event 24 Node Listing 25 Subcat 1S: DevCo Graf 1S DevCo Graf 2P Detention Facility Routing Diagram for TB-Graf St Prepared by Kimley-Horn & Associates, Printed 8/8/2025 HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Subcat Reach Pond Link Type II 24-hr First 0.5 Rainfall=0.50"TB-Graf St Printed 4/1/2025Prepared by Kimley-Horn & Associates HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Events for Pond 2P: Detention Facility Event Inflow (cfs) Primary (cfs) Elevation (feet) Storage (cubic-feet) 2yr 5.47 0.11 2.87 13,227 5yr 8.09 0.63 3.27 15,483 10yr 9.93 1.39 3.59 17,282 25yr 12.25 2.32 4.15 20,228 50yr 13.96 2.94 4.70 22,621 100yr 15.68 3.64 5.46 25,105 First 0.5 0.70 0.04 0.48 1,488 TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 2HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Rainfall Events Listing (selected events) Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 2yr Type II 24-hr Default 24.00 1 1.18 2 2 5yr Type II 24-hr Default 24.00 1 1.49 2 3 10yr Type II 24-hr Default 24.00 1 1.70 2 4 25yr Type II 24-hr Default 24.00 1 1.96 2 5 50yr Type II 24-hr Default 24.00 1 2.15 2 6 100yr Type II 24-hr Default 24.00 1 2.34 2 TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 3HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 6.790 98 (1S) 2.400 74 >75% Grass cover, Good, HSG C (1S) 9.190 92 TOTAL AREA TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 4HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.000 HSG A 0.000 HSG B 2.400 HSG C 1S 0.000 HSG D 6.790 Other 1S 9.190 TOTAL AREA TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 5HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.000 0.000 0.000 0.000 6.790 6.790 1S 0.000 0.000 2.400 0.000 0.000 2.400 >75% Grass cover, Good 1S 0.000 0.000 2.400 0.000 6.790 9.190 TOTAL AREA Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 6HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.03 hrs, 1201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 73.88% Impervious Runoff Depth=0.54"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=92 Runoff=5.47 cfs 0.413 af Peak Elev=2.87' Storage=13,227 cf Inflow=5.47 cfs 0.413 afPond 2P: Detention Facility Outflow=0.11 cfs 0.213 af Total Runoff Area = 9.190 ac Runoff Volume = 0.413 af Average Runoff Depth = 0.54" 26.12% Pervious = 2.400 ac 73.88% Impervious = 6.790 ac Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 7HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff = 5.47 cfs @ 12.13 hrs, Volume= 0.413 af, Depth= 0.54" Routed to Pond 2P : Detention Facility Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Type II 24-hr 2yr Rainfall=1.18" Area (ac) CN Description * 6.790 98 2.400 74 >75% Grass cover, Good, HSG C 9.190 92 Weighted Average 2.400 26.12% Pervious Area 6.790 73.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 20.0 Direct Entry, Proposed Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)6 5 4 3 2 1 0 Type II 24-hr 2yr Rainfall=1.18" Runoff Area=9.190 ac Runoff Volume=0.413 af Runoff Depth=0.54" Tc=20.0 min CN=92 5.47 cfs Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 8HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 0.00 0.00 0.00 0.00 0.60 0.01 0.00 0.00 1.20 0.02 0.00 0.00 1.80 0.02 0.00 0.00 2.40 0.03 0.00 0.00 3.00 0.04 0.00 0.00 3.60 0.05 0.00 0.00 4.20 0.06 0.00 0.00 4.80 0.07 0.00 0.00 5.40 0.08 0.00 0.00 6.00 0.09 0.00 0.00 6.60 0.11 0.00 0.00 7.20 0.12 0.00 0.00 7.80 0.14 0.00 0.00 8.40 0.15 0.00 0.00 9.00 0.17 0.00 0.00 9.60 0.20 0.00 0.01 10.20 0.22 0.00 0.03 10.80 0.26 0.01 0.08 11.40 0.32 0.02 0.20 12.00 0.78 0.25 3.53 12.60 0.88 0.31 1.20 13.20 0.92 0.35 0.52 13.80 0.96 0.37 0.37 14.40 0.98 0.39 0.29 15.00 1.01 0.41 0.26 15.60 1.03 0.42 0.23 16.20 1.04 0.44 0.19 16.80 1.06 0.45 0.18 17.40 1.07 0.46 0.17 18.00 1.09 0.47 0.16 18.60 1.10 0.48 0.14 19.20 1.11 0.49 0.13 19.80 1.12 0.49 0.12 20.40 1.13 0.50 0.11 21.00 1.14 0.51 0.11 21.60 1.15 0.51 0.10 22.20 1.16 0.52 0.10 22.80 1.16 0.53 0.10 23.40 1.17 0.53 0.10 24.00 1.18 0.54 0.10 24.60 1.18 0.54 0.00 25.20 1.18 0.54 0.00 25.80 1.18 0.54 0.00 26.40 1.18 0.54 0.00 27.00 1.18 0.54 0.00 27.60 1.18 0.54 0.00 28.20 1.18 0.54 0.00 28.80 1.18 0.54 0.00 29.40 1.18 0.54 0.00 30.00 1.18 0.54 0.00 30.60 1.18 0.54 0.00 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 31.20 1.18 0.54 0.00 31.80 1.18 0.54 0.00 32.40 1.18 0.54 0.00 33.00 1.18 0.54 0.00 33.60 1.18 0.54 0.00 34.20 1.18 0.54 0.00 34.80 1.18 0.54 0.00 35.40 1.18 0.54 0.00 36.00 1.18 0.54 0.00 Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 9HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: Detention Facility Inflow Area = 9.190 ac, 73.88% Impervious, Inflow Depth = 0.54" for 2yr event Inflow = 5.47 cfs @ 12.13 hrs, Volume= 0.413 af Outflow = 0.11 cfs @ 20.18 hrs, Volume= 0.213 af, Atten= 98%, Lag= 482.8 min Primary = 0.11 cfs @ 20.18 hrs, Volume= 0.213 af Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Peak Elev= 2.87' @ 20.18 hrs Storage= 13,227 cf Plug-Flow detention time= 698.8 min calculated for 0.213 af (52% of inflow) Center-of-Mass det. time= 574.8 min ( 1,424.3 - 849.5 ) Volume Invert Avail.Storage Storage Description #1 0.00' 25,201 cf Custom Stage Data Listed below Elevation Cum.Store (feet) (cubic-feet) 0.00 0 1.00 3,117 2.00 8,247 3.00 14,000 4.00 19,555 5.00 23,965 5.50 25,200 6.50 25,201 Device Routing Invert Outlet Devices #1 Primary 0.00'1.6" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Primary 2.87'9.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 5.50'15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 3.59'3.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.11 cfs @ 20.18 hrs HW=2.87' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.11 cfs @ 8.06 fps) 2=Orifice/Grate ( Controls 0.00 cfs) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 10HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Pond 2P: Detention Facility Inflow Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)6 5 4 3 2 1 0 Inflow Area=9.190 ac Peak Elev=2.87' Storage=13,227 cf 5.47 cfs 0.11 cfs Pond 2P: Detention Facility Storage Stage-Area-Storage Storage (cubic-feet) 24,00022,00020,00018,00016,00014,00012,00010,0008,0006,0004,0002,0000Elevation (feet)6 5 4 3 2 1 0 Custom Stage Data Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 11HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: Detention Facility Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 0.00 0.00 1.50 0.00 0 0.00 0.00 3.00 0.00 0 0.00 0.00 4.50 0.00 0 0.00 0.00 6.00 0.00 0 0.00 0.00 7.50 0.00 0 0.00 0.00 9.00 0.00 0 0.00 0.00 10.50 0.05 87 0.03 0.00 12.00 3.53 2,213 0.71 0.05 13.50 0.44 10,981 2.48 0.10 15.00 0.26 12,143 2.68 0.11 16.50 0.19 12,734 2.78 0.11 18.00 0.16 13,054 2.84 0.11 19.50 0.13 13,211 2.86 0.11 21.00 0.11 13,217 2.86 0.11 22.50 0.10 13,173 2.86 0.11 24.00 0.10 13,100 2.84 0.11 25.50 0.00 12,605 2.76 0.11 27.00 0.00 12,015 2.65 0.11 28.50 0.00 11,437 2.55 0.11 30.00 0.00 10,870 2.46 0.10 31.50 0.00 10,314 2.36 0.10 33.00 0.00 9,770 2.26 0.10 34.50 0.00 9,238 2.17 0.10 36.00 0.00 8,717 2.08 0.10 Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 12HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Discharge for Pond 2P: Detention Facility Elevation (feet) Primary (cfs) 0.00 0.00 0.05 0.00 0.10 0.01 0.15 0.02 0.20 0.02 0.25 0.03 0.30 0.03 0.35 0.04 0.40 0.04 0.45 0.04 0.50 0.04 0.55 0.05 0.60 0.05 0.65 0.05 0.70 0.05 0.75 0.06 0.80 0.06 0.85 0.06 0.90 0.06 0.95 0.06 1.00 0.06 1.05 0.07 1.10 0.07 1.15 0.07 1.20 0.07 1.25 0.07 1.30 0.07 1.35 0.08 1.40 0.08 1.45 0.08 1.50 0.08 1.55 0.08 1.60 0.08 1.65 0.08 1.70 0.09 1.75 0.09 1.80 0.09 1.85 0.09 1.90 0.09 1.95 0.09 2.00 0.09 2.05 0.09 2.10 0.10 2.15 0.10 2.20 0.10 2.25 0.10 2.30 0.10 2.35 0.10 2.40 0.10 2.45 0.10 2.50 0.10 2.55 0.11 Elevation (feet) Primary (cfs) 2.60 0.11 2.65 0.11 2.70 0.11 2.75 0.11 2.80 0.11 2.85 0.11 2.90 0.12 2.95 0.14 3.00 0.18 3.05 0.23 3.10 0.30 3.15 0.39 3.20 0.49 3.25 0.59 3.30 0.71 3.35 0.83 3.40 0.95 3.45 1.07 3.50 1.20 3.55 1.31 3.60 1.40 3.65 1.49 3.70 1.59 3.75 1.69 3.80 1.78 3.85 1.87 3.90 1.95 3.95 2.03 4.00 2.11 4.05 2.18 4.10 2.25 4.15 2.32 4.20 2.38 4.25 2.44 4.30 2.50 4.35 2.56 4.40 2.62 4.45 2.68 4.50 2.73 4.55 2.79 4.60 2.84 4.65 2.89 4.70 2.95 4.75 3.00 4.80 3.05 4.85 3.09 4.90 3.14 4.95 3.19 5.00 3.24 5.05 3.28 5.10 3.33 5.15 3.37 Elevation (feet) Primary (cfs) 5.20 3.41 5.25 3.46 5.30 3.50 5.35 3.54 5.40 3.58 5.45 3.63 5.50 3.67 5.55 3.85 5.60 4.15 5.65 4.53 5.70 4.97 5.75 5.47 5.80 6.01 5.85 6.60 5.90 7.23 5.95 7.89 6.00 8.23 6.05 8.47 6.10 8.70 6.15 8.92 6.20 9.14 6.25 9.35 6.30 9.55 6.35 9.75 6.40 9.94 6.45 10.13 6.50 10.31 Type II 24-hr 2yr Rainfall=1.18"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 13HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: Detention Facility Elevation (feet) Storage (cubic-feet) 0.00 0 0.05 156 0.10 312 0.15 468 0.20 623 0.25 779 0.30 935 0.35 1,091 0.40 1,247 0.45 1,403 0.50 1,559 0.55 1,714 0.60 1,870 0.65 2,026 0.70 2,182 0.75 2,338 0.80 2,494 0.85 2,649 0.90 2,805 0.95 2,961 1.00 3,117 1.05 3,374 1.10 3,630 1.15 3,887 1.20 4,143 1.25 4,400 1.30 4,656 1.35 4,913 1.40 5,169 1.45 5,426 1.50 5,682 1.55 5,939 1.60 6,195 1.65 6,452 1.70 6,708 1.75 6,965 1.80 7,221 1.85 7,478 1.90 7,734 1.95 7,991 2.00 8,247 2.05 8,535 2.10 8,822 2.15 9,110 2.20 9,398 2.25 9,685 2.30 9,973 2.35 10,261 2.40 10,548 2.45 10,836 2.50 11,124 2.55 11,411 Elevation (feet) Storage (cubic-feet) 2.60 11,699 2.65 11,986 2.70 12,274 2.75 12,562 2.80 12,849 2.85 13,137 2.90 13,425 2.95 13,712 3.00 14,000 3.05 14,278 3.10 14,556 3.15 14,833 3.20 15,111 3.25 15,389 3.30 15,667 3.35 15,944 3.40 16,222 3.45 16,500 3.50 16,778 3.55 17,055 3.60 17,333 3.65 17,611 3.70 17,889 3.75 18,166 3.80 18,444 3.85 18,722 3.90 19,000 3.95 19,277 4.00 19,555 4.05 19,776 4.10 19,996 4.15 20,217 4.20 20,437 4.25 20,658 4.30 20,878 4.35 21,099 4.40 21,319 4.45 21,540 4.50 21,760 4.55 21,981 4.60 22,201 4.65 22,422 4.70 22,642 4.75 22,863 4.80 23,083 4.85 23,304 4.90 23,524 4.95 23,745 5.00 23,965 5.05 24,089 5.10 24,212 5.15 24,336 Elevation (feet) Storage (cubic-feet) 5.20 24,459 5.25 24,583 5.30 24,706 5.35 24,830 5.40 24,953 5.45 25,077 5.50 25,200 5.55 25,200 5.60 25,200 5.65 25,200 5.70 25,200 5.75 25,200 5.80 25,200 5.85 25,200 5.90 25,200 5.95 25,200 6.00 25,201 6.05 25,201 6.10 25,201 6.15 25,201 6.20 25,201 6.25 25,201 6.30 25,201 6.35 25,201 6.40 25,201 6.45 25,201 6.50 25,201 Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 14HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.03 hrs, 1201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 73.88% Impervious Runoff Depth=0.79"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=92 Runoff=8.09 cfs 0.607 af Peak Elev=3.27' Storage=15,483 cf Inflow=8.09 cfs 0.607 afPond 2P: Detention Facility Outflow=0.63 cfs 0.395 af Total Runoff Area = 9.190 ac Runoff Volume = 0.607 af Average Runoff Depth = 0.79" 26.12% Pervious = 2.400 ac 73.88% Impervious = 6.790 ac Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 15HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff = 8.09 cfs @ 12.13 hrs, Volume= 0.607 af, Depth= 0.79" Routed to Pond 2P : Detention Facility Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Type II 24-hr 5yr Rainfall=1.49" Area (ac) CN Description * 6.790 98 2.400 74 >75% Grass cover, Good, HSG C 9.190 92 Weighted Average 2.400 26.12% Pervious Area 6.790 73.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 20.0 Direct Entry, Proposed Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)9 8 7 6 5 4 3 2 1 0 Type II 24-hr 5yr Rainfall=1.49" Runoff Area=9.190 ac Runoff Volume=0.607 af Runoff Depth=0.79" Tc=20.0 min CN=92 8.09 cfs Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 16HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 0.00 0.00 0.00 0.00 0.60 0.01 0.00 0.00 1.20 0.02 0.00 0.00 1.80 0.03 0.00 0.00 2.40 0.04 0.00 0.00 3.00 0.05 0.00 0.00 3.60 0.06 0.00 0.00 4.20 0.08 0.00 0.00 4.80 0.09 0.00 0.00 5.40 0.10 0.00 0.00 6.00 0.12 0.00 0.00 6.60 0.14 0.00 0.00 7.20 0.15 0.00 0.00 7.80 0.17 0.00 0.00 8.40 0.19 0.00 0.01 9.00 0.22 0.00 0.03 9.60 0.25 0.01 0.05 10.20 0.28 0.01 0.09 10.80 0.33 0.02 0.18 11.40 0.40 0.05 0.37 12.00 0.99 0.39 5.42 12.60 1.11 0.48 1.71 13.20 1.17 0.53 0.72 13.80 1.21 0.56 0.52 14.40 1.24 0.59 0.40 15.00 1.27 0.61 0.36 15.60 1.30 0.63 0.31 16.20 1.32 0.65 0.27 16.80 1.34 0.67 0.25 17.40 1.36 0.68 0.23 18.00 1.37 0.69 0.21 18.60 1.39 0.71 0.20 19.20 1.40 0.72 0.18 19.80 1.41 0.73 0.16 20.40 1.43 0.74 0.15 21.00 1.44 0.75 0.15 21.60 1.45 0.76 0.14 22.20 1.46 0.77 0.14 22.80 1.47 0.78 0.14 23.40 1.48 0.78 0.13 24.00 1.49 0.79 0.13 24.60 1.49 0.79 0.01 25.20 1.49 0.79 0.00 25.80 1.49 0.79 0.00 26.40 1.49 0.79 0.00 27.00 1.49 0.79 0.00 27.60 1.49 0.79 0.00 28.20 1.49 0.79 0.00 28.80 1.49 0.79 0.00 29.40 1.49 0.79 0.00 30.00 1.49 0.79 0.00 30.60 1.49 0.79 0.00 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 31.20 1.49 0.79 0.00 31.80 1.49 0.79 0.00 32.40 1.49 0.79 0.00 33.00 1.49 0.79 0.00 33.60 1.49 0.79 0.00 34.20 1.49 0.79 0.00 34.80 1.49 0.79 0.00 35.40 1.49 0.79 0.00 36.00 1.49 0.79 0.00 Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 17HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: Detention Facility Inflow Area = 9.190 ac, 73.88% Impervious, Inflow Depth = 0.79" for 5yr event Inflow = 8.09 cfs @ 12.13 hrs, Volume= 0.607 af Outflow = 0.63 cfs @ 13.42 hrs, Volume= 0.395 af, Atten= 92%, Lag= 77.5 min Primary = 0.63 cfs @ 13.42 hrs, Volume= 0.395 af Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Peak Elev= 3.27' @ 13.42 hrs Storage= 15,483 cf Plug-Flow detention time= 481.9 min calculated for 0.395 af (65% of inflow) Center-of-Mass det. time= 372.4 min ( 1,210.9 - 838.5 ) Volume Invert Avail.Storage Storage Description #1 0.00' 25,201 cf Custom Stage Data Listed below Elevation Cum.Store (feet) (cubic-feet) 0.00 0 1.00 3,117 2.00 8,247 3.00 14,000 4.00 19,555 5.00 23,965 5.50 25,200 6.50 25,201 Device Routing Invert Outlet Devices #1 Primary 0.00'1.6" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Primary 2.87'9.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 5.50'15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 3.59'3.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.63 cfs @ 13.42 hrs HW=3.27' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.12 cfs @ 8.61 fps) 2=Orifice/Grate (Orifice Controls 0.51 cfs @ 2.15 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 18HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Pond 2P: Detention Facility Inflow Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)9 8 7 6 5 4 3 2 1 0 Inflow Area=9.190 ac Peak Elev=3.27' Storage=15,483 cf 8.09 cfs 0.63 cfs Pond 2P: Detention Facility Storage Stage-Area-Storage Storage (cubic-feet) 24,00022,00020,00018,00016,00014,00012,00010,0008,0006,0004,0002,0000Elevation (feet)6 5 4 3 2 1 0 Custom Stage Data Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 19HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: Detention Facility Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 0.00 0.00 1.50 0.00 0 0.00 0.00 3.00 0.00 0 0.00 0.00 4.50 0.00 0 0.00 0.00 6.00 0.00 0 0.00 0.00 7.50 0.00 0 0.00 0.00 9.00 0.03 36 0.01 0.00 10.50 0.13 371 0.12 0.02 12.00 5.42 3,967 1.17 0.07 13.50 0.60 15,479 3.27 0.63 15.00 0.36 14,979 3.18 0.44 16.50 0.25 14,589 3.11 0.32 18.00 0.21 14,338 3.06 0.25 19.50 0.17 14,147 3.03 0.21 21.00 0.15 13,964 2.99 0.17 22.50 0.14 13,843 2.97 0.16 24.00 0.13 13,747 2.96 0.15 25.50 0.00 13,205 2.86 0.11 27.00 0.00 12,604 2.76 0.11 28.50 0.00 12,014 2.65 0.11 30.00 0.00 11,436 2.55 0.11 31.50 0.00 10,869 2.46 0.10 33.00 0.00 10,314 2.36 0.10 34.50 0.00 9,770 2.26 0.10 36.00 0.00 9,237 2.17 0.10 Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 20HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Discharge for Pond 2P: Detention Facility Elevation (feet) Primary (cfs) 0.00 0.00 0.05 0.00 0.10 0.01 0.15 0.02 0.20 0.02 0.25 0.03 0.30 0.03 0.35 0.04 0.40 0.04 0.45 0.04 0.50 0.04 0.55 0.05 0.60 0.05 0.65 0.05 0.70 0.05 0.75 0.06 0.80 0.06 0.85 0.06 0.90 0.06 0.95 0.06 1.00 0.06 1.05 0.07 1.10 0.07 1.15 0.07 1.20 0.07 1.25 0.07 1.30 0.07 1.35 0.08 1.40 0.08 1.45 0.08 1.50 0.08 1.55 0.08 1.60 0.08 1.65 0.08 1.70 0.09 1.75 0.09 1.80 0.09 1.85 0.09 1.90 0.09 1.95 0.09 2.00 0.09 2.05 0.09 2.10 0.10 2.15 0.10 2.20 0.10 2.25 0.10 2.30 0.10 2.35 0.10 2.40 0.10 2.45 0.10 2.50 0.10 2.55 0.11 Elevation (feet) Primary (cfs) 2.60 0.11 2.65 0.11 2.70 0.11 2.75 0.11 2.80 0.11 2.85 0.11 2.90 0.12 2.95 0.14 3.00 0.18 3.05 0.23 3.10 0.30 3.15 0.39 3.20 0.49 3.25 0.59 3.30 0.71 3.35 0.83 3.40 0.95 3.45 1.07 3.50 1.20 3.55 1.31 3.60 1.40 3.65 1.49 3.70 1.59 3.75 1.69 3.80 1.78 3.85 1.87 3.90 1.95 3.95 2.03 4.00 2.11 4.05 2.18 4.10 2.25 4.15 2.32 4.20 2.38 4.25 2.44 4.30 2.50 4.35 2.56 4.40 2.62 4.45 2.68 4.50 2.73 4.55 2.79 4.60 2.84 4.65 2.89 4.70 2.95 4.75 3.00 4.80 3.05 4.85 3.09 4.90 3.14 4.95 3.19 5.00 3.24 5.05 3.28 5.10 3.33 5.15 3.37 Elevation (feet) Primary (cfs) 5.20 3.41 5.25 3.46 5.30 3.50 5.35 3.54 5.40 3.58 5.45 3.63 5.50 3.67 5.55 3.85 5.60 4.15 5.65 4.53 5.70 4.97 5.75 5.47 5.80 6.01 5.85 6.60 5.90 7.23 5.95 7.89 6.00 8.23 6.05 8.47 6.10 8.70 6.15 8.92 6.20 9.14 6.25 9.35 6.30 9.55 6.35 9.75 6.40 9.94 6.45 10.13 6.50 10.31 Type II 24-hr 5yr Rainfall=1.49"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 21HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: Detention Facility Elevation (feet) Storage (cubic-feet) 0.00 0 0.05 156 0.10 312 0.15 468 0.20 623 0.25 779 0.30 935 0.35 1,091 0.40 1,247 0.45 1,403 0.50 1,559 0.55 1,714 0.60 1,870 0.65 2,026 0.70 2,182 0.75 2,338 0.80 2,494 0.85 2,649 0.90 2,805 0.95 2,961 1.00 3,117 1.05 3,374 1.10 3,630 1.15 3,887 1.20 4,143 1.25 4,400 1.30 4,656 1.35 4,913 1.40 5,169 1.45 5,426 1.50 5,682 1.55 5,939 1.60 6,195 1.65 6,452 1.70 6,708 1.75 6,965 1.80 7,221 1.85 7,478 1.90 7,734 1.95 7,991 2.00 8,247 2.05 8,535 2.10 8,822 2.15 9,110 2.20 9,398 2.25 9,685 2.30 9,973 2.35 10,261 2.40 10,548 2.45 10,836 2.50 11,124 2.55 11,411 Elevation (feet) Storage (cubic-feet) 2.60 11,699 2.65 11,986 2.70 12,274 2.75 12,562 2.80 12,849 2.85 13,137 2.90 13,425 2.95 13,712 3.00 14,000 3.05 14,278 3.10 14,556 3.15 14,833 3.20 15,111 3.25 15,389 3.30 15,667 3.35 15,944 3.40 16,222 3.45 16,500 3.50 16,778 3.55 17,055 3.60 17,333 3.65 17,611 3.70 17,889 3.75 18,166 3.80 18,444 3.85 18,722 3.90 19,000 3.95 19,277 4.00 19,555 4.05 19,776 4.10 19,996 4.15 20,217 4.20 20,437 4.25 20,658 4.30 20,878 4.35 21,099 4.40 21,319 4.45 21,540 4.50 21,760 4.55 21,981 4.60 22,201 4.65 22,422 4.70 22,642 4.75 22,863 4.80 23,083 4.85 23,304 4.90 23,524 4.95 23,745 5.00 23,965 5.05 24,089 5.10 24,212 5.15 24,336 Elevation (feet) Storage (cubic-feet) 5.20 24,459 5.25 24,583 5.30 24,706 5.35 24,830 5.40 24,953 5.45 25,077 5.50 25,200 5.55 25,200 5.60 25,200 5.65 25,200 5.70 25,200 5.75 25,200 5.80 25,200 5.85 25,200 5.90 25,200 5.95 25,200 6.00 25,201 6.05 25,201 6.10 25,201 6.15 25,201 6.20 25,201 6.25 25,201 6.30 25,201 6.35 25,201 6.40 25,201 6.45 25,201 6.50 25,201 Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 22HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.03 hrs, 1201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 73.88% Impervious Runoff Depth=0.97"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=92 Runoff=9.93 cfs 0.745 af Peak Elev=3.59' Storage=17,282 cf Inflow=9.93 cfs 0.745 afPond 2P: Detention Facility Outflow=1.39 cfs 0.530 af Total Runoff Area = 9.190 ac Runoff Volume = 0.745 af Average Runoff Depth = 0.97" 26.12% Pervious = 2.400 ac 73.88% Impervious = 6.790 ac Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 23HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff = 9.93 cfs @ 12.13 hrs, Volume= 0.745 af, Depth= 0.97" Routed to Pond 2P : Detention Facility Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Type II 24-hr 10yr Rainfall=1.70" Area (ac) CN Description * 6.790 98 2.400 74 >75% Grass cover, Good, HSG C 9.190 92 Weighted Average 2.400 26.12% Pervious Area 6.790 73.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 20.0 Direct Entry, Proposed Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10yr Rainfall=1.70" Runoff Area=9.190 ac Runoff Volume=0.745 af Runoff Depth=0.97" Tc=20.0 min CN=92 9.93 cfs Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 24HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 0.00 0.00 0.00 0.00 0.60 0.01 0.00 0.00 1.20 0.02 0.00 0.00 1.80 0.03 0.00 0.00 2.40 0.05 0.00 0.00 3.00 0.06 0.00 0.00 3.60 0.07 0.00 0.00 4.20 0.09 0.00 0.00 4.80 0.10 0.00 0.00 5.40 0.12 0.00 0.00 6.00 0.14 0.00 0.00 6.60 0.15 0.00 0.00 7.20 0.18 0.00 0.00 7.80 0.20 0.00 0.01 8.40 0.22 0.00 0.03 9.00 0.25 0.01 0.06 9.60 0.28 0.01 0.09 10.20 0.32 0.02 0.14 10.80 0.38 0.04 0.25 11.40 0.46 0.07 0.50 12.00 1.13 0.50 6.77 12.60 1.26 0.61 2.05 13.20 1.33 0.66 0.86 13.80 1.38 0.70 0.62 14.40 1.42 0.73 0.48 15.00 1.45 0.76 0.42 15.60 1.48 0.78 0.37 16.20 1.50 0.80 0.32 16.80 1.53 0.82 0.29 17.40 1.55 0.84 0.27 18.00 1.57 0.86 0.25 18.60 1.58 0.87 0.23 19.20 1.60 0.89 0.21 19.80 1.61 0.90 0.19 20.40 1.63 0.91 0.18 21.00 1.64 0.92 0.17 21.60 1.65 0.93 0.17 22.20 1.66 0.94 0.16 22.80 1.68 0.95 0.16 23.40 1.69 0.96 0.16 24.00 1.70 0.97 0.15 24.60 1.70 0.97 0.01 25.20 1.70 0.97 0.00 25.80 1.70 0.97 0.00 26.40 1.70 0.97 0.00 27.00 1.70 0.97 0.00 27.60 1.70 0.97 0.00 28.20 1.70 0.97 0.00 28.80 1.70 0.97 0.00 29.40 1.70 0.97 0.00 30.00 1.70 0.97 0.00 30.60 1.70 0.97 0.00 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 31.20 1.70 0.97 0.00 31.80 1.70 0.97 0.00 32.40 1.70 0.97 0.00 33.00 1.70 0.97 0.00 33.60 1.70 0.97 0.00 34.20 1.70 0.97 0.00 34.80 1.70 0.97 0.00 35.40 1.70 0.97 0.00 36.00 1.70 0.97 0.00 Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 25HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: Detention Facility Inflow Area = 9.190 ac, 73.88% Impervious, Inflow Depth = 0.97" for 10yr event Inflow = 9.93 cfs @ 12.13 hrs, Volume= 0.745 af Outflow = 1.39 cfs @ 12.77 hrs, Volume= 0.530 af, Atten= 86%, Lag= 38.8 min Primary = 1.39 cfs @ 12.77 hrs, Volume= 0.530 af Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Peak Elev= 3.59' @ 12.77 hrs Storage= 17,282 cf Plug-Flow detention time= 389.9 min calculated for 0.530 af (71% of inflow) Center-of-Mass det. time= 289.8 min ( 1,122.4 - 832.7 ) Volume Invert Avail.Storage Storage Description #1 0.00' 25,201 cf Custom Stage Data Listed below Elevation Cum.Store (feet) (cubic-feet) 0.00 0 1.00 3,117 2.00 8,247 3.00 14,000 4.00 19,555 5.00 23,965 5.50 25,200 6.50 25,201 Device Routing Invert Outlet Devices #1 Primary 0.00'1.6" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Primary 2.87'9.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 5.50'15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 3.59'3.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=1.39 cfs @ 12.77 hrs HW=3.59' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.13 cfs @ 9.04 fps) 2=Orifice/Grate (Orifice Controls 1.26 cfs @ 2.89 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.09 fps) Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 26HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Pond 2P: Detention Facility Inflow Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=9.190 ac Peak Elev=3.59' Storage=17,282 cf 9.93 cfs 1.39 cfs Pond 2P: Detention Facility Storage Stage-Area-Storage Storage (cubic-feet) 24,00022,00020,00018,00016,00014,00012,00010,0008,0006,0004,0002,0000Elevation (feet)6 5 4 3 2 1 0 Custom Stage Data Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 27HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: Detention Facility Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 0.00 0.00 1.50 0.00 0 0.00 0.00 3.00 0.00 0 0.00 0.00 4.50 0.00 0 0.00 0.00 6.00 0.00 0 0.00 0.00 7.50 0.00 1 0.00 0.00 9.00 0.06 125 0.04 0.00 10.50 0.19 644 0.21 0.03 12.00 6.77 5,339 1.43 0.08 13.50 0.72 16,476 3.45 1.06 15.00 0.42 15,264 3.23 0.54 16.50 0.30 14,770 3.14 0.37 18.00 0.25 14,499 3.09 0.29 19.50 0.20 14,297 3.05 0.24 21.00 0.17 14,104 3.02 0.20 22.50 0.16 13,995 3.00 0.18 24.00 0.15 13,920 2.99 0.17 25.50 0.00 13,335 2.88 0.12 27.00 0.00 12,730 2.78 0.11 28.50 0.00 12,138 2.68 0.11 30.00 0.00 11,558 2.58 0.11 31.50 0.00 10,988 2.48 0.10 33.00 0.00 10,430 2.38 0.10 34.50 0.00 9,884 2.28 0.10 36.00 0.00 9,349 2.19 0.10 Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 28HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Discharge for Pond 2P: Detention Facility Elevation (feet) Primary (cfs) 0.00 0.00 0.05 0.00 0.10 0.01 0.15 0.02 0.20 0.02 0.25 0.03 0.30 0.03 0.35 0.04 0.40 0.04 0.45 0.04 0.50 0.04 0.55 0.05 0.60 0.05 0.65 0.05 0.70 0.05 0.75 0.06 0.80 0.06 0.85 0.06 0.90 0.06 0.95 0.06 1.00 0.06 1.05 0.07 1.10 0.07 1.15 0.07 1.20 0.07 1.25 0.07 1.30 0.07 1.35 0.08 1.40 0.08 1.45 0.08 1.50 0.08 1.55 0.08 1.60 0.08 1.65 0.08 1.70 0.09 1.75 0.09 1.80 0.09 1.85 0.09 1.90 0.09 1.95 0.09 2.00 0.09 2.05 0.09 2.10 0.10 2.15 0.10 2.20 0.10 2.25 0.10 2.30 0.10 2.35 0.10 2.40 0.10 2.45 0.10 2.50 0.10 2.55 0.11 Elevation (feet) Primary (cfs) 2.60 0.11 2.65 0.11 2.70 0.11 2.75 0.11 2.80 0.11 2.85 0.11 2.90 0.12 2.95 0.14 3.00 0.18 3.05 0.23 3.10 0.30 3.15 0.39 3.20 0.49 3.25 0.59 3.30 0.71 3.35 0.83 3.40 0.95 3.45 1.07 3.50 1.20 3.55 1.31 3.60 1.40 3.65 1.49 3.70 1.59 3.75 1.69 3.80 1.78 3.85 1.87 3.90 1.95 3.95 2.03 4.00 2.11 4.05 2.18 4.10 2.25 4.15 2.32 4.20 2.38 4.25 2.44 4.30 2.50 4.35 2.56 4.40 2.62 4.45 2.68 4.50 2.73 4.55 2.79 4.60 2.84 4.65 2.89 4.70 2.95 4.75 3.00 4.80 3.05 4.85 3.09 4.90 3.14 4.95 3.19 5.00 3.24 5.05 3.28 5.10 3.33 5.15 3.37 Elevation (feet) Primary (cfs) 5.20 3.41 5.25 3.46 5.30 3.50 5.35 3.54 5.40 3.58 5.45 3.63 5.50 3.67 5.55 3.85 5.60 4.15 5.65 4.53 5.70 4.97 5.75 5.47 5.80 6.01 5.85 6.60 5.90 7.23 5.95 7.89 6.00 8.23 6.05 8.47 6.10 8.70 6.15 8.92 6.20 9.14 6.25 9.35 6.30 9.55 6.35 9.75 6.40 9.94 6.45 10.13 6.50 10.31 Type II 24-hr 10yr Rainfall=1.70"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 29HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: Detention Facility Elevation (feet) Storage (cubic-feet) 0.00 0 0.05 156 0.10 312 0.15 468 0.20 623 0.25 779 0.30 935 0.35 1,091 0.40 1,247 0.45 1,403 0.50 1,559 0.55 1,714 0.60 1,870 0.65 2,026 0.70 2,182 0.75 2,338 0.80 2,494 0.85 2,649 0.90 2,805 0.95 2,961 1.00 3,117 1.05 3,374 1.10 3,630 1.15 3,887 1.20 4,143 1.25 4,400 1.30 4,656 1.35 4,913 1.40 5,169 1.45 5,426 1.50 5,682 1.55 5,939 1.60 6,195 1.65 6,452 1.70 6,708 1.75 6,965 1.80 7,221 1.85 7,478 1.90 7,734 1.95 7,991 2.00 8,247 2.05 8,535 2.10 8,822 2.15 9,110 2.20 9,398 2.25 9,685 2.30 9,973 2.35 10,261 2.40 10,548 2.45 10,836 2.50 11,124 2.55 11,411 Elevation (feet) Storage (cubic-feet) 2.60 11,699 2.65 11,986 2.70 12,274 2.75 12,562 2.80 12,849 2.85 13,137 2.90 13,425 2.95 13,712 3.00 14,000 3.05 14,278 3.10 14,556 3.15 14,833 3.20 15,111 3.25 15,389 3.30 15,667 3.35 15,944 3.40 16,222 3.45 16,500 3.50 16,778 3.55 17,055 3.60 17,333 3.65 17,611 3.70 17,889 3.75 18,166 3.80 18,444 3.85 18,722 3.90 19,000 3.95 19,277 4.00 19,555 4.05 19,776 4.10 19,996 4.15 20,217 4.20 20,437 4.25 20,658 4.30 20,878 4.35 21,099 4.40 21,319 4.45 21,540 4.50 21,760 4.55 21,981 4.60 22,201 4.65 22,422 4.70 22,642 4.75 22,863 4.80 23,083 4.85 23,304 4.90 23,524 4.95 23,745 5.00 23,965 5.05 24,089 5.10 24,212 5.15 24,336 Elevation (feet) Storage (cubic-feet) 5.20 24,459 5.25 24,583 5.30 24,706 5.35 24,830 5.40 24,953 5.45 25,077 5.50 25,200 5.55 25,200 5.60 25,200 5.65 25,200 5.70 25,200 5.75 25,200 5.80 25,200 5.85 25,200 5.90 25,200 5.95 25,200 6.00 25,201 6.05 25,201 6.10 25,201 6.15 25,201 6.20 25,201 6.25 25,201 6.30 25,201 6.35 25,201 6.40 25,201 6.45 25,201 6.50 25,201 Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 30HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.03 hrs, 1201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 73.88% Impervious Runoff Depth=1.20"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=92 Runoff=12.25 cfs 0.920 af Peak Elev=4.15' Storage=20,228 cf Inflow=12.25 cfs 0.920 afPond 2P: Detention Facility Outflow=2.32 cfs 0.703 af Total Runoff Area = 9.190 ac Runoff Volume = 0.920 af Average Runoff Depth = 1.20" 26.12% Pervious = 2.400 ac 73.88% Impervious = 6.790 ac Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 31HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff = 12.25 cfs @ 12.12 hrs, Volume= 0.920 af, Depth= 1.20" Routed to Pond 2P : Detention Facility Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Type II 24-hr 25yr Rainfall=1.96" Area (ac) CN Description * 6.790 98 2.400 74 >75% Grass cover, Good, HSG C 9.190 92 Weighted Average 2.400 26.12% Pervious Area 6.790 73.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 20.0 Direct Entry, Proposed Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 25yr Rainfall=1.96" Runoff Area=9.190 ac Runoff Volume=0.920 af Runoff Depth=1.20" Tc=20.0 min CN=92 12.25 cfs Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 32HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 0.00 0.00 0.00 0.00 0.60 0.01 0.00 0.00 1.20 0.02 0.00 0.00 1.80 0.04 0.00 0.00 2.40 0.05 0.00 0.00 3.00 0.07 0.00 0.00 3.60 0.08 0.00 0.00 4.20 0.10 0.00 0.00 4.80 0.12 0.00 0.00 5.40 0.14 0.00 0.00 6.00 0.16 0.00 0.00 6.60 0.18 0.00 0.00 7.20 0.20 0.00 0.01 7.80 0.23 0.00 0.03 8.40 0.25 0.01 0.06 9.00 0.29 0.01 0.10 9.60 0.33 0.02 0.14 10.20 0.37 0.04 0.21 10.80 0.43 0.06 0.35 11.40 0.53 0.10 0.67 12.00 1.30 0.63 8.47 12.60 1.46 0.76 2.48 13.20 1.54 0.83 1.03 13.80 1.59 0.88 0.74 14.40 1.64 0.92 0.57 15.00 1.67 0.95 0.50 15.60 1.71 0.98 0.44 16.20 1.73 1.00 0.38 16.80 1.76 1.02 0.35 17.40 1.78 1.04 0.32 18.00 1.81 1.06 0.30 18.60 1.83 1.08 0.28 19.20 1.84 1.10 0.25 19.80 1.86 1.11 0.23 20.40 1.88 1.13 0.21 21.00 1.89 1.14 0.20 21.60 1.91 1.15 0.20 22.20 1.92 1.17 0.19 22.80 1.93 1.18 0.19 23.40 1.95 1.19 0.19 24.00 1.96 1.20 0.18 24.60 1.96 1.20 0.01 25.20 1.96 1.20 0.00 25.80 1.96 1.20 0.00 26.40 1.96 1.20 0.00 27.00 1.96 1.20 0.00 27.60 1.96 1.20 0.00 28.20 1.96 1.20 0.00 28.80 1.96 1.20 0.00 29.40 1.96 1.20 0.00 30.00 1.96 1.20 0.00 30.60 1.96 1.20 0.00 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 31.20 1.96 1.20 0.00 31.80 1.96 1.20 0.00 32.40 1.96 1.20 0.00 33.00 1.96 1.20 0.00 33.60 1.96 1.20 0.00 34.20 1.96 1.20 0.00 34.80 1.96 1.20 0.00 35.40 1.96 1.20 0.00 36.00 1.96 1.20 0.00 Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 33HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: Detention Facility Inflow Area = 9.190 ac, 73.88% Impervious, Inflow Depth = 1.20" for 25yr event Inflow = 12.25 cfs @ 12.12 hrs, Volume= 0.920 af Outflow = 2.32 cfs @ 12.63 hrs, Volume= 0.703 af, Atten= 81%, Lag= 30.1 min Primary = 2.32 cfs @ 12.63 hrs, Volume= 0.703 af Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Peak Elev= 4.15' @ 12.63 hrs Storage= 20,228 cf Plug-Flow detention time= 320.6 min calculated for 0.703 af (76% of inflow) Center-of-Mass det. time= 231.4 min ( 1,058.0 - 826.6 ) Volume Invert Avail.Storage Storage Description #1 0.00' 25,201 cf Custom Stage Data Listed below Elevation Cum.Store (feet) (cubic-feet) 0.00 0 1.00 3,117 2.00 8,247 3.00 14,000 4.00 19,555 5.00 23,965 5.50 25,200 6.50 25,201 Device Routing Invert Outlet Devices #1 Primary 0.00'1.6" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Primary 2.87'9.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 5.50'15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 3.59'3.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.32 cfs @ 12.63 hrs HW=4.15' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.14 cfs @ 9.73 fps) 2=Orifice/Grate (Orifice Controls 2.03 cfs @ 4.59 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate (Orifice Controls 0.16 cfs @ 3.18 fps) Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 34HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Pond 2P: Detention Facility Inflow Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=9.190 ac Peak Elev=4.15' Storage=20,228 cf 12.25 cfs 2.32 cfs Pond 2P: Detention Facility Storage Stage-Area-Storage Storage (cubic-feet) 24,00022,00020,00018,00016,00014,00012,00010,0008,0006,0004,0002,0000Elevation (feet)6 5 4 3 2 1 0 Custom Stage Data Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 35HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: Detention Facility Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 0.00 0.00 1.50 0.00 0 0.00 0.00 3.00 0.00 0 0.00 0.00 4.50 0.00 0 0.00 0.00 6.00 0.00 0 0.00 0.00 7.50 0.02 29 0.01 0.00 9.00 0.10 297 0.10 0.01 10.50 0.27 1,069 0.34 0.04 12.00 8.47 7,206 1.80 0.09 13.50 0.86 17,927 3.71 1.60 15.00 0.50 15,614 3.29 0.68 16.50 0.36 14,978 3.18 0.44 18.00 0.30 14,677 3.12 0.34 19.50 0.24 14,459 3.08 0.28 21.00 0.20 14,260 3.05 0.23 22.50 0.19 14,149 3.03 0.21 24.00 0.18 14,074 3.01 0.19 25.50 0.00 13,441 2.90 0.12 27.00 0.00 12,830 2.80 0.11 28.50 0.00 12,236 2.69 0.11 30.00 0.00 11,653 2.59 0.11 31.50 0.00 11,082 2.49 0.10 33.00 0.00 10,522 2.40 0.10 34.50 0.00 9,974 2.30 0.10 36.00 0.00 9,437 2.21 0.10 Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 36HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Discharge for Pond 2P: Detention Facility Elevation (feet) Primary (cfs) 0.00 0.00 0.05 0.00 0.10 0.01 0.15 0.02 0.20 0.02 0.25 0.03 0.30 0.03 0.35 0.04 0.40 0.04 0.45 0.04 0.50 0.04 0.55 0.05 0.60 0.05 0.65 0.05 0.70 0.05 0.75 0.06 0.80 0.06 0.85 0.06 0.90 0.06 0.95 0.06 1.00 0.06 1.05 0.07 1.10 0.07 1.15 0.07 1.20 0.07 1.25 0.07 1.30 0.07 1.35 0.08 1.40 0.08 1.45 0.08 1.50 0.08 1.55 0.08 1.60 0.08 1.65 0.08 1.70 0.09 1.75 0.09 1.80 0.09 1.85 0.09 1.90 0.09 1.95 0.09 2.00 0.09 2.05 0.09 2.10 0.10 2.15 0.10 2.20 0.10 2.25 0.10 2.30 0.10 2.35 0.10 2.40 0.10 2.45 0.10 2.50 0.10 2.55 0.11 Elevation (feet) Primary (cfs) 2.60 0.11 2.65 0.11 2.70 0.11 2.75 0.11 2.80 0.11 2.85 0.11 2.90 0.12 2.95 0.14 3.00 0.18 3.05 0.23 3.10 0.30 3.15 0.39 3.20 0.49 3.25 0.59 3.30 0.71 3.35 0.83 3.40 0.95 3.45 1.07 3.50 1.20 3.55 1.31 3.60 1.40 3.65 1.49 3.70 1.59 3.75 1.69 3.80 1.78 3.85 1.87 3.90 1.95 3.95 2.03 4.00 2.11 4.05 2.18 4.10 2.25 4.15 2.32 4.20 2.38 4.25 2.44 4.30 2.50 4.35 2.56 4.40 2.62 4.45 2.68 4.50 2.73 4.55 2.79 4.60 2.84 4.65 2.89 4.70 2.95 4.75 3.00 4.80 3.05 4.85 3.09 4.90 3.14 4.95 3.19 5.00 3.24 5.05 3.28 5.10 3.33 5.15 3.37 Elevation (feet) Primary (cfs) 5.20 3.41 5.25 3.46 5.30 3.50 5.35 3.54 5.40 3.58 5.45 3.63 5.50 3.67 5.55 3.85 5.60 4.15 5.65 4.53 5.70 4.97 5.75 5.47 5.80 6.01 5.85 6.60 5.90 7.23 5.95 7.89 6.00 8.23 6.05 8.47 6.10 8.70 6.15 8.92 6.20 9.14 6.25 9.35 6.30 9.55 6.35 9.75 6.40 9.94 6.45 10.13 6.50 10.31 Type II 24-hr 25yr Rainfall=1.96"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 37HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: Detention Facility Elevation (feet) Storage (cubic-feet) 0.00 0 0.05 156 0.10 312 0.15 468 0.20 623 0.25 779 0.30 935 0.35 1,091 0.40 1,247 0.45 1,403 0.50 1,559 0.55 1,714 0.60 1,870 0.65 2,026 0.70 2,182 0.75 2,338 0.80 2,494 0.85 2,649 0.90 2,805 0.95 2,961 1.00 3,117 1.05 3,374 1.10 3,630 1.15 3,887 1.20 4,143 1.25 4,400 1.30 4,656 1.35 4,913 1.40 5,169 1.45 5,426 1.50 5,682 1.55 5,939 1.60 6,195 1.65 6,452 1.70 6,708 1.75 6,965 1.80 7,221 1.85 7,478 1.90 7,734 1.95 7,991 2.00 8,247 2.05 8,535 2.10 8,822 2.15 9,110 2.20 9,398 2.25 9,685 2.30 9,973 2.35 10,261 2.40 10,548 2.45 10,836 2.50 11,124 2.55 11,411 Elevation (feet) Storage (cubic-feet) 2.60 11,699 2.65 11,986 2.70 12,274 2.75 12,562 2.80 12,849 2.85 13,137 2.90 13,425 2.95 13,712 3.00 14,000 3.05 14,278 3.10 14,556 3.15 14,833 3.20 15,111 3.25 15,389 3.30 15,667 3.35 15,944 3.40 16,222 3.45 16,500 3.50 16,778 3.55 17,055 3.60 17,333 3.65 17,611 3.70 17,889 3.75 18,166 3.80 18,444 3.85 18,722 3.90 19,000 3.95 19,277 4.00 19,555 4.05 19,776 4.10 19,996 4.15 20,217 4.20 20,437 4.25 20,658 4.30 20,878 4.35 21,099 4.40 21,319 4.45 21,540 4.50 21,760 4.55 21,981 4.60 22,201 4.65 22,422 4.70 22,642 4.75 22,863 4.80 23,083 4.85 23,304 4.90 23,524 4.95 23,745 5.00 23,965 5.05 24,089 5.10 24,212 5.15 24,336 Elevation (feet) Storage (cubic-feet) 5.20 24,459 5.25 24,583 5.30 24,706 5.35 24,830 5.40 24,953 5.45 25,077 5.50 25,200 5.55 25,200 5.60 25,200 5.65 25,200 5.70 25,200 5.75 25,200 5.80 25,200 5.85 25,200 5.90 25,200 5.95 25,200 6.00 25,201 6.05 25,201 6.10 25,201 6.15 25,201 6.20 25,201 6.25 25,201 6.30 25,201 6.35 25,201 6.40 25,201 6.45 25,201 6.50 25,201 Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 38HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.03 hrs, 1201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 73.88% Impervious Runoff Depth=1.37"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=92 Runoff=13.96 cfs 1.051 af Peak Elev=4.70' Storage=22,621 cf Inflow=13.96 cfs 1.051 afPond 2P: Detention Facility Outflow=2.94 cfs 0.833 af Total Runoff Area = 9.190 ac Runoff Volume = 1.051 af Average Runoff Depth = 1.37" 26.12% Pervious = 2.400 ac 73.88% Impervious = 6.790 ac Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 39HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff = 13.96 cfs @ 12.12 hrs, Volume= 1.051 af, Depth= 1.37" Routed to Pond 2P : Detention Facility Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Type II 24-hr 50yr Rainfall=2.15" Area (ac) CN Description * 6.790 98 2.400 74 >75% Grass cover, Good, HSG C 9.190 92 Weighted Average 2.400 26.12% Pervious Area 6.790 73.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 20.0 Direct Entry, Proposed Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 50yr Rainfall=2.15" Runoff Area=9.190 ac Runoff Volume=1.051 af Runoff Depth=1.37" Tc=20.0 min CN=92 13.96 cfs Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 40HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 0.00 0.00 0.00 0.00 0.60 0.01 0.00 0.00 1.20 0.03 0.00 0.00 1.80 0.04 0.00 0.00 2.40 0.06 0.00 0.00 3.00 0.07 0.00 0.00 3.60 0.09 0.00 0.00 4.20 0.11 0.00 0.00 4.80 0.13 0.00 0.00 5.40 0.15 0.00 0.00 6.00 0.17 0.00 0.00 6.60 0.20 0.00 0.01 7.20 0.22 0.00 0.03 7.80 0.25 0.01 0.05 8.40 0.28 0.01 0.08 9.00 0.32 0.02 0.13 9.60 0.36 0.03 0.18 10.20 0.41 0.05 0.27 10.80 0.48 0.08 0.43 11.40 0.58 0.13 0.81 12.00 1.43 0.74 9.74 12.60 1.60 0.88 2.80 13.20 1.68 0.96 1.16 13.80 1.75 1.01 0.83 14.40 1.79 1.05 0.64 15.00 1.84 1.09 0.56 15.60 1.87 1.12 0.49 16.20 1.90 1.15 0.42 16.80 1.93 1.17 0.39 17.40 1.96 1.20 0.36 18.00 1.98 1.22 0.33 18.60 2.00 1.24 0.31 19.20 2.02 1.26 0.28 19.80 2.04 1.27 0.26 20.40 2.06 1.29 0.23 21.00 2.07 1.30 0.23 21.60 2.09 1.32 0.22 22.20 2.11 1.33 0.22 22.80 2.12 1.35 0.21 23.40 2.14 1.36 0.21 24.00 2.15 1.37 0.20 24.60 2.15 1.37 0.01 25.20 2.15 1.37 0.00 25.80 2.15 1.37 0.00 26.40 2.15 1.37 0.00 27.00 2.15 1.37 0.00 27.60 2.15 1.37 0.00 28.20 2.15 1.37 0.00 28.80 2.15 1.37 0.00 29.40 2.15 1.37 0.00 30.00 2.15 1.37 0.00 30.60 2.15 1.37 0.00 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 31.20 2.15 1.37 0.00 31.80 2.15 1.37 0.00 32.40 2.15 1.37 0.00 33.00 2.15 1.37 0.00 33.60 2.15 1.37 0.00 34.20 2.15 1.37 0.00 34.80 2.15 1.37 0.00 35.40 2.15 1.37 0.00 36.00 2.15 1.37 0.00 Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 41HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: Detention Facility Inflow Area = 9.190 ac, 73.88% Impervious, Inflow Depth = 1.37" for 50yr event Inflow = 13.96 cfs @ 12.12 hrs, Volume= 1.051 af Outflow = 2.94 cfs @ 12.58 hrs, Volume= 0.833 af, Atten= 79%, Lag= 27.5 min Primary = 2.94 cfs @ 12.58 hrs, Volume= 0.833 af Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Peak Elev= 4.70' @ 12.58 hrs Storage= 22,621 cf Plug-Flow detention time= 287.4 min calculated for 0.833 af (79% of inflow) Center-of-Mass det. time= 204.7 min ( 1,027.5 - 822.8 ) Volume Invert Avail.Storage Storage Description #1 0.00' 25,201 cf Custom Stage Data Listed below Elevation Cum.Store (feet) (cubic-feet) 0.00 0 1.00 3,117 2.00 8,247 3.00 14,000 4.00 19,555 5.00 23,965 5.50 25,200 6.50 25,201 Device Routing Invert Outlet Devices #1 Primary 0.00'1.6" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Primary 2.87'9.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 5.50'15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 3.59'3.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.94 cfs @ 12.58 hrs HW=4.69' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.14 cfs @ 10.36 fps) 2=Orifice/Grate (Orifice Controls 2.56 cfs @ 5.80 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate (Orifice Controls 0.23 cfs @ 4.77 fps) Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 42HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Pond 2P: Detention Facility Inflow Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=9.190 ac Peak Elev=4.70' Storage=22,621 cf 13.96 cfs 2.94 cfs Pond 2P: Detention Facility Storage Stage-Area-Storage Storage (cubic-feet) 24,00022,00020,00018,00016,00014,00012,00010,0008,0006,0004,0002,0000Elevation (feet)6 5 4 3 2 1 0 Custom Stage Data Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 43HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: Detention Facility Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 0.00 0.00 1.50 0.00 0 0.00 0.00 3.00 0.00 0 0.00 0.00 4.50 0.00 0 0.00 0.00 6.00 0.00 0 0.00 0.00 7.50 0.04 79 0.03 0.00 9.00 0.13 455 0.15 0.02 10.50 0.34 1,436 0.46 0.04 12.00 9.74 8,670 2.07 0.10 13.50 0.97 19,180 3.93 2.01 15.00 0.56 15,904 3.34 0.81 16.50 0.40 15,121 3.20 0.49 18.00 0.33 14,795 3.14 0.38 19.50 0.27 14,570 3.10 0.31 21.00 0.23 14,358 3.06 0.25 22.50 0.21 14,254 3.05 0.23 24.00 0.20 14,178 3.03 0.21 25.50 0.00 13,504 2.91 0.12 27.00 0.00 12,888 2.81 0.11 28.50 0.00 12,292 2.70 0.11 30.00 0.00 11,709 2.60 0.11 31.50 0.00 11,136 2.50 0.10 33.00 0.00 10,575 2.40 0.10 34.50 0.00 10,026 2.31 0.10 36.00 0.00 9,488 2.22 0.10 Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 44HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Discharge for Pond 2P: Detention Facility Elevation (feet) Primary (cfs) 0.00 0.00 0.05 0.00 0.10 0.01 0.15 0.02 0.20 0.02 0.25 0.03 0.30 0.03 0.35 0.04 0.40 0.04 0.45 0.04 0.50 0.04 0.55 0.05 0.60 0.05 0.65 0.05 0.70 0.05 0.75 0.06 0.80 0.06 0.85 0.06 0.90 0.06 0.95 0.06 1.00 0.06 1.05 0.07 1.10 0.07 1.15 0.07 1.20 0.07 1.25 0.07 1.30 0.07 1.35 0.08 1.40 0.08 1.45 0.08 1.50 0.08 1.55 0.08 1.60 0.08 1.65 0.08 1.70 0.09 1.75 0.09 1.80 0.09 1.85 0.09 1.90 0.09 1.95 0.09 2.00 0.09 2.05 0.09 2.10 0.10 2.15 0.10 2.20 0.10 2.25 0.10 2.30 0.10 2.35 0.10 2.40 0.10 2.45 0.10 2.50 0.10 2.55 0.11 Elevation (feet) Primary (cfs) 2.60 0.11 2.65 0.11 2.70 0.11 2.75 0.11 2.80 0.11 2.85 0.11 2.90 0.12 2.95 0.14 3.00 0.18 3.05 0.23 3.10 0.30 3.15 0.39 3.20 0.49 3.25 0.59 3.30 0.71 3.35 0.83 3.40 0.95 3.45 1.07 3.50 1.20 3.55 1.31 3.60 1.40 3.65 1.49 3.70 1.59 3.75 1.69 3.80 1.78 3.85 1.87 3.90 1.95 3.95 2.03 4.00 2.11 4.05 2.18 4.10 2.25 4.15 2.32 4.20 2.38 4.25 2.44 4.30 2.50 4.35 2.56 4.40 2.62 4.45 2.68 4.50 2.73 4.55 2.79 4.60 2.84 4.65 2.89 4.70 2.95 4.75 3.00 4.80 3.05 4.85 3.09 4.90 3.14 4.95 3.19 5.00 3.24 5.05 3.28 5.10 3.33 5.15 3.37 Elevation (feet) Primary (cfs) 5.20 3.41 5.25 3.46 5.30 3.50 5.35 3.54 5.40 3.58 5.45 3.63 5.50 3.67 5.55 3.85 5.60 4.15 5.65 4.53 5.70 4.97 5.75 5.47 5.80 6.01 5.85 6.60 5.90 7.23 5.95 7.89 6.00 8.23 6.05 8.47 6.10 8.70 6.15 8.92 6.20 9.14 6.25 9.35 6.30 9.55 6.35 9.75 6.40 9.94 6.45 10.13 6.50 10.31 Type II 24-hr 50yr Rainfall=2.15"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 45HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: Detention Facility Elevation (feet) Storage (cubic-feet) 0.00 0 0.05 156 0.10 312 0.15 468 0.20 623 0.25 779 0.30 935 0.35 1,091 0.40 1,247 0.45 1,403 0.50 1,559 0.55 1,714 0.60 1,870 0.65 2,026 0.70 2,182 0.75 2,338 0.80 2,494 0.85 2,649 0.90 2,805 0.95 2,961 1.00 3,117 1.05 3,374 1.10 3,630 1.15 3,887 1.20 4,143 1.25 4,400 1.30 4,656 1.35 4,913 1.40 5,169 1.45 5,426 1.50 5,682 1.55 5,939 1.60 6,195 1.65 6,452 1.70 6,708 1.75 6,965 1.80 7,221 1.85 7,478 1.90 7,734 1.95 7,991 2.00 8,247 2.05 8,535 2.10 8,822 2.15 9,110 2.20 9,398 2.25 9,685 2.30 9,973 2.35 10,261 2.40 10,548 2.45 10,836 2.50 11,124 2.55 11,411 Elevation (feet) Storage (cubic-feet) 2.60 11,699 2.65 11,986 2.70 12,274 2.75 12,562 2.80 12,849 2.85 13,137 2.90 13,425 2.95 13,712 3.00 14,000 3.05 14,278 3.10 14,556 3.15 14,833 3.20 15,111 3.25 15,389 3.30 15,667 3.35 15,944 3.40 16,222 3.45 16,500 3.50 16,778 3.55 17,055 3.60 17,333 3.65 17,611 3.70 17,889 3.75 18,166 3.80 18,444 3.85 18,722 3.90 19,000 3.95 19,277 4.00 19,555 4.05 19,776 4.10 19,996 4.15 20,217 4.20 20,437 4.25 20,658 4.30 20,878 4.35 21,099 4.40 21,319 4.45 21,540 4.50 21,760 4.55 21,981 4.60 22,201 4.65 22,422 4.70 22,642 4.75 22,863 4.80 23,083 4.85 23,304 4.90 23,524 4.95 23,745 5.00 23,965 5.05 24,089 5.10 24,212 5.15 24,336 Elevation (feet) Storage (cubic-feet) 5.20 24,459 5.25 24,583 5.30 24,706 5.35 24,830 5.40 24,953 5.45 25,077 5.50 25,200 5.55 25,200 5.60 25,200 5.65 25,200 5.70 25,200 5.75 25,200 5.80 25,200 5.85 25,200 5.90 25,200 5.95 25,200 6.00 25,201 6.05 25,201 6.10 25,201 6.15 25,201 6.20 25,201 6.25 25,201 6.30 25,201 6.35 25,201 6.40 25,201 6.45 25,201 6.50 25,201 Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 46HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.03 hrs, 1201 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=9.190 ac 73.88% Impervious Runoff Depth=1.55"Subcatchment 1S: DevCo Graf Tc=20.0 min CN=92 Runoff=15.68 cfs 1.184 af Peak Elev=5.46' Storage=25,105 cf Inflow=15.68 cfs 1.184 afPond 2P: Detention Facility Outflow=3.64 cfs 0.965 af Total Runoff Area = 9.190 ac Runoff Volume = 1.184 af Average Runoff Depth = 1.55" 26.12% Pervious = 2.400 ac 73.88% Impervious = 6.790 ac Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 47HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: DevCo Graf Runoff = 15.68 cfs @ 12.12 hrs, Volume= 1.184 af, Depth= 1.55" Routed to Pond 2P : Detention Facility Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Type II 24-hr 100yr Rainfall=2.34" Area (ac) CN Description * 6.790 98 2.400 74 >75% Grass cover, Good, HSG C 9.190 92 Weighted Average 2.400 26.12% Pervious Area 6.790 73.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 20.0 Direct Entry, Proposed Subcatchment 1S: DevCo Graf Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100yr Rainfall=2.34" Runoff Area=9.190 ac Runoff Volume=1.184 af Runoff Depth=1.55" Tc=20.0 min CN=92 15.68 cfs Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 48HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 1S: DevCo Graf Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 0.00 0.00 0.00 0.00 0.60 0.01 0.00 0.00 1.20 0.03 0.00 0.00 1.80 0.05 0.00 0.00 2.40 0.06 0.00 0.00 3.00 0.08 0.00 0.00 3.60 0.10 0.00 0.00 4.20 0.12 0.00 0.00 4.80 0.14 0.00 0.00 5.40 0.16 0.00 0.00 6.00 0.19 0.00 0.00 6.60 0.21 0.00 0.02 7.20 0.24 0.00 0.05 7.80 0.27 0.01 0.07 8.40 0.30 0.02 0.11 9.00 0.34 0.03 0.17 9.60 0.39 0.04 0.23 10.20 0.44 0.06 0.32 10.80 0.52 0.10 0.51 11.40 0.64 0.16 0.94 12.00 1.55 0.84 11.02 12.60 1.74 1.01 3.11 13.20 1.83 1.09 1.28 13.80 1.90 1.15 0.92 14.40 1.95 1.19 0.71 15.00 2.00 1.23 0.62 15.60 2.04 1.27 0.54 16.20 2.07 1.30 0.46 16.80 2.10 1.33 0.43 17.40 2.13 1.35 0.40 18.00 2.16 1.38 0.37 18.60 2.18 1.40 0.34 19.20 2.20 1.42 0.31 19.80 2.22 1.44 0.28 20.40 2.24 1.45 0.26 21.00 2.26 1.47 0.25 21.60 2.27 1.49 0.24 22.20 2.29 1.50 0.24 22.80 2.31 1.52 0.23 23.40 2.32 1.53 0.23 24.00 2.34 1.55 0.22 24.60 2.34 1.55 0.01 25.20 2.34 1.55 0.00 25.80 2.34 1.55 0.00 26.40 2.34 1.55 0.00 27.00 2.34 1.55 0.00 27.60 2.34 1.55 0.00 28.20 2.34 1.55 0.00 28.80 2.34 1.55 0.00 29.40 2.34 1.55 0.00 30.00 2.34 1.55 0.00 30.60 2.34 1.55 0.00 Time (hours) Precip. (inches) Excess (inches) Runoff (cfs) 31.20 2.34 1.55 0.00 31.80 2.34 1.55 0.00 32.40 2.34 1.55 0.00 33.00 2.34 1.55 0.00 33.60 2.34 1.55 0.00 34.20 2.34 1.55 0.00 34.80 2.34 1.55 0.00 35.40 2.34 1.55 0.00 36.00 2.34 1.55 0.00 Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 49HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: Detention Facility Inflow Area = 9.190 ac, 73.88% Impervious, Inflow Depth = 1.55" for 100yr event Inflow = 15.68 cfs @ 12.12 hrs, Volume= 1.184 af Outflow = 3.64 cfs @ 12.55 hrs, Volume= 0.965 af, Atten= 77%, Lag= 25.4 min Primary = 3.64 cfs @ 12.55 hrs, Volume= 0.965 af Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.03 hrs Peak Elev= 5.46' @ 12.55 hrs Storage= 25,105 cf Plug-Flow detention time= 262.7 min calculated for 0.964 af (81% of inflow) Center-of-Mass det. time= 185.5 min ( 1,005.0 - 819.5 ) Volume Invert Avail.Storage Storage Description #1 0.00' 25,201 cf Custom Stage Data Listed below Elevation Cum.Store (feet) (cubic-feet) 0.00 0 1.00 3,117 2.00 8,247 3.00 14,000 4.00 19,555 5.00 23,965 5.50 25,200 6.50 25,201 Device Routing Invert Outlet Devices #1 Primary 0.00'1.6" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Primary 2.87'9.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 5.50'15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 3.59'3.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=3.63 cfs @ 12.55 hrs HW=5.46' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.16 cfs @ 11.18 fps) 2=Orifice/Grate (Orifice Controls 3.17 cfs @ 7.17 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate (Orifice Controls 0.31 cfs @ 6.36 fps) Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 50HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Pond 2P: Detention Facility Inflow Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210Flow (cfs)17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=9.190 ac Peak Elev=5.46' Storage=25,105 cf 15.68 cfs 3.64 cfs Pond 2P: Detention Facility Storage Stage-Area-Storage Storage (cubic-feet) 24,00022,00020,00018,00016,00014,00012,00010,0008,0006,0004,0002,0000Elevation (feet)6 5 4 3 2 1 0 Custom Stage Data Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 51HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: Detention Facility Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 0.00 0.00 1.50 0.00 0 0.00 0.00 3.00 0.00 0 0.00 0.00 4.50 0.00 0 0.00 0.00 6.00 0.00 1 0.00 0.00 7.50 0.06 153 0.05 0.00 9.00 0.17 641 0.21 0.02 10.50 0.40 1,846 0.59 0.05 12.00 11.02 10,206 2.34 0.10 13.50 1.07 20,546 4.22 2.41 15.00 0.62 16,238 3.40 0.96 16.50 0.44 15,263 3.23 0.54 18.00 0.37 14,910 3.16 0.42 19.50 0.30 14,672 3.12 0.34 21.00 0.25 14,452 3.08 0.28 22.50 0.24 14,344 3.06 0.25 24.00 0.22 14,276 3.05 0.23 25.50 0.00 13,559 2.92 0.12 27.00 0.00 12,937 2.82 0.11 28.50 0.00 12,341 2.71 0.11 30.00 0.00 11,756 2.61 0.11 31.50 0.00 11,183 2.51 0.11 33.00 0.00 10,621 2.41 0.10 34.50 0.00 10,071 2.32 0.10 36.00 0.00 9,532 2.22 0.10 Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 52HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Discharge for Pond 2P: Detention Facility Elevation (feet) Primary (cfs) 0.00 0.00 0.05 0.00 0.10 0.01 0.15 0.02 0.20 0.02 0.25 0.03 0.30 0.03 0.35 0.04 0.40 0.04 0.45 0.04 0.50 0.04 0.55 0.05 0.60 0.05 0.65 0.05 0.70 0.05 0.75 0.06 0.80 0.06 0.85 0.06 0.90 0.06 0.95 0.06 1.00 0.06 1.05 0.07 1.10 0.07 1.15 0.07 1.20 0.07 1.25 0.07 1.30 0.07 1.35 0.08 1.40 0.08 1.45 0.08 1.50 0.08 1.55 0.08 1.60 0.08 1.65 0.08 1.70 0.09 1.75 0.09 1.80 0.09 1.85 0.09 1.90 0.09 1.95 0.09 2.00 0.09 2.05 0.09 2.10 0.10 2.15 0.10 2.20 0.10 2.25 0.10 2.30 0.10 2.35 0.10 2.40 0.10 2.45 0.10 2.50 0.10 2.55 0.11 Elevation (feet) Primary (cfs) 2.60 0.11 2.65 0.11 2.70 0.11 2.75 0.11 2.80 0.11 2.85 0.11 2.90 0.12 2.95 0.14 3.00 0.18 3.05 0.23 3.10 0.30 3.15 0.39 3.20 0.49 3.25 0.59 3.30 0.71 3.35 0.83 3.40 0.95 3.45 1.07 3.50 1.20 3.55 1.31 3.60 1.40 3.65 1.49 3.70 1.59 3.75 1.69 3.80 1.78 3.85 1.87 3.90 1.95 3.95 2.03 4.00 2.11 4.05 2.18 4.10 2.25 4.15 2.32 4.20 2.38 4.25 2.44 4.30 2.50 4.35 2.56 4.40 2.62 4.45 2.68 4.50 2.73 4.55 2.79 4.60 2.84 4.65 2.89 4.70 2.95 4.75 3.00 4.80 3.05 4.85 3.09 4.90 3.14 4.95 3.19 5.00 3.24 5.05 3.28 5.10 3.33 5.15 3.37 Elevation (feet) Primary (cfs) 5.20 3.41 5.25 3.46 5.30 3.50 5.35 3.54 5.40 3.58 5.45 3.63 5.50 3.67 5.55 3.85 5.60 4.15 5.65 4.53 5.70 4.97 5.75 5.47 5.80 6.01 5.85 6.60 5.90 7.23 5.95 7.89 6.00 8.23 6.05 8.47 6.10 8.70 6.15 8.92 6.20 9.14 6.25 9.35 6.30 9.55 6.35 9.75 6.40 9.94 6.45 10.13 6.50 10.31 Type II 24-hr 100yr Rainfall=2.34"TB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates Page 53HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: Detention Facility Elevation (feet) Storage (cubic-feet) 0.00 0 0.05 156 0.10 312 0.15 468 0.20 623 0.25 779 0.30 935 0.35 1,091 0.40 1,247 0.45 1,403 0.50 1,559 0.55 1,714 0.60 1,870 0.65 2,026 0.70 2,182 0.75 2,338 0.80 2,494 0.85 2,649 0.90 2,805 0.95 2,961 1.00 3,117 1.05 3,374 1.10 3,630 1.15 3,887 1.20 4,143 1.25 4,400 1.30 4,656 1.35 4,913 1.40 5,169 1.45 5,426 1.50 5,682 1.55 5,939 1.60 6,195 1.65 6,452 1.70 6,708 1.75 6,965 1.80 7,221 1.85 7,478 1.90 7,734 1.95 7,991 2.00 8,247 2.05 8,535 2.10 8,822 2.15 9,110 2.20 9,398 2.25 9,685 2.30 9,973 2.35 10,261 2.40 10,548 2.45 10,836 2.50 11,124 2.55 11,411 Elevation (feet) Storage (cubic-feet) 2.60 11,699 2.65 11,986 2.70 12,274 2.75 12,562 2.80 12,849 2.85 13,137 2.90 13,425 2.95 13,712 3.00 14,000 3.05 14,278 3.10 14,556 3.15 14,833 3.20 15,111 3.25 15,389 3.30 15,667 3.35 15,944 3.40 16,222 3.45 16,500 3.50 16,778 3.55 17,055 3.60 17,333 3.65 17,611 3.70 17,889 3.75 18,166 3.80 18,444 3.85 18,722 3.90 19,000 3.95 19,277 4.00 19,555 4.05 19,776 4.10 19,996 4.15 20,217 4.20 20,437 4.25 20,658 4.30 20,878 4.35 21,099 4.40 21,319 4.45 21,540 4.50 21,760 4.55 21,981 4.60 22,201 4.65 22,422 4.70 22,642 4.75 22,863 4.80 23,083 4.85 23,304 4.90 23,524 4.95 23,745 5.00 23,965 5.05 24,089 5.10 24,212 5.15 24,336 Elevation (feet) Storage (cubic-feet) 5.20 24,459 5.25 24,583 5.30 24,706 5.35 24,830 5.40 24,953 5.45 25,077 5.50 25,200 5.55 25,200 5.60 25,200 5.65 25,200 5.70 25,200 5.75 25,200 5.80 25,200 5.85 25,200 5.90 25,200 5.95 25,200 6.00 25,201 6.05 25,201 6.10 25,201 6.15 25,201 6.20 25,201 6.25 25,201 6.30 25,201 6.35 25,201 6.40 25,201 6.45 25,201 6.50 25,201 Table of ContentsTB-Graf St Printed 8/8/2025Prepared by Kimley-Horn & Associates HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC TABLE OF CONTENTS Project Reports 1 Routing Diagram 2 Rainfall Events Listing (selected events) 3 Area Listing (all nodes) 4 Soil Listing (all nodes) 5 Ground Covers (all nodes) 2yr Event 6 Node Listing 7 Subcat 1S: DevCo Graf 9 Pond 2P: Detention Facility 5yr Event 14 Node Listing 15 Subcat 1S: DevCo Graf 17 Pond 2P: Detention Facility 10yr Event 22 Node Listing 23 Subcat 1S: DevCo Graf 25 Pond 2P: Detention Facility 25yr Event 30 Node Listing 31 Subcat 1S: DevCo Graf 33 Pond 2P: Detention Facility 50yr Event 38 Node Listing 39 Subcat 1S: DevCo Graf 41 Pond 2P: Detention Facility 100yr Event 46 Node Listing 47 Subcat 1S: DevCo Graf 49 Pond 2P: Detention Facility Alder Ridge and Sage Peak Apartments Bozeman, MT Kimley-Horn and Associates, Inc. Preliminary Drainage Report PROJECT NAME: CLIENT NAME: KH PROJECT Building 0.9 Paving & Sidewalk 0.9 Landscape 0.1 Building (SF) =88,577 Landscaping (SF) =107,158 Sidewalk & Paving (SF) =204,581 Total (SF) =400,316 A (ac) =9.19 I (in/hr)*0.41 Cw 0.69 Qmax (cfs)2.6 Volume = 7200*Q Volume Required (cf)18606 Alder Ridge and Sage Peak Apartments DevCo *Design Storm is 10-yr 2-hr storm per Design Standards Land Use Areas Runoff Coefficients (C) 090071010 Post-Development Flow Calculations Detention Volume Calculation Alder Ridge & Sage Peak Apartments Kimley-Horn and Associates, Inc. Bozeman, MT Final Drainage Report August 2025 Page 8 APPENDIX D: CONVEYANCE AND WATER QUALITY CALCULATIONS FlexTable: Conduit Table Flow / Capacity (Design) (%) Hydraulic Grade Line (Out) (ft) Hydraulic Grade Line (In) (ft) Elevation Ground (ft) Velocit y (ft/s) Flow (cfs) Slope (ft/ft) Diam (in) Label 50.14,973.554,973.984,976.933.201.260.00512.0PIPE - 09 49.44,972.644,973.514,975.364.071.580.00812.0PIPE - 10 28.04,973.344,974.294,976.092.850.730.00512.0PIPE - 17 47.84,973.034,973.234,974.983.181.200.00512.0PIPE - 18 50.74,971.304,972.644,974.434.971.970.01212.0PIPE - 11 58.74,969.014,973.034,973.508.013.550.02912.0PIPE - 19 20.34,967.924,971.304,972.577.862.500.03615.0PIPE - 12 55.14,969.014,969.214,973.504.304.090.00518.0PIPE - 06 61.04,967.924,969.014,972.575.359.770.00524.0PIPE - 07 42.34,969.324,970.094,973.163.561.930.00515.0PIPE - 04 39.54,969.214,969.324,972.603.932.910.00518.0PIPE - 05 39.14,967.924,967.994,972.623.131.020.00512.0PIPE -13 46.34,967.464,967.924,972.584.333.610.00618.0PIPE -15 51.34,967.564,967.924,972.045.9915.000.00530.0PIPE - 08 11.04,963.294,963.964,971.9913.0115.380.04430.0PIPE - 08 (2) 55.84,967.334,967.464,971.264.534.340.00518.0PIPE -16 75.04,967.264,967.334,971.274.645.600.00518.0PIPE -16 (2) 16.24,973.234,973.574,976.092.360.410.00512.0PIPE - 26 27.54,972.874,973.044,975.360.670.23-0.0058.0PIPE - 33 0.04,971.304,971.304,973.320.000.00-0.0158.0CO-5 57.54,970.684,971.224,972.623.172.49-0.01512.0CO-6 24.04,969.144,969.464,973.332.010.200.0058.0CO-8 23.64,969.004,969.144,974.242.630.600.00512.0CO-9 37.64,968.704,969.004,972.992.980.950.00512.0CO-10 51.44,968.554,968.700.004.361.750.00912.0CO-11 44.54,969.254,969.444,974.241.090.38-0.0058.0CO-12 42.64,971.304,972.144,974.433.970.610.0148.0PIPE - 37 28.14,970.794,971.054,973.292.021.59-0.02512.0PIPE - 30 46.44,967.924,969.674,972.577.092.630.02512.0PIPE - 23 12.84,971.064,971.074,974.000.410.32-0.00512.0PIPE - 32 30.44,971.054,971.064,973.680.960.75-0.00512.0PIPE - 31 25.34,966.164,966.744,971.893.431.280.00615.0PIPE -21(STRM)(1) 25.04,965.574,966.184,970.363.471.280.00615.0PIPE -21 (STRM)(2) Page 1 of 176 Watertown Road, Suite 2D Thomaston, CT 06787 USA +1-203-755-1666 4/1/2025 StormCAD [10.04.00.158] Bentley Systems, Inc. Haestad Methods Solution CenterStormCAD-Graf-TB.stsw 10 Year FlexTable: Conduit Table Flow / Capacity (Design) (%) Hydraulic Grade Line (Out) (ft) Hydraulic Grade Line (In) (ft) Elevation Ground (ft) Velocit y (ft/s) Flow (cfs) Slope (ft/ft) Diam (in) Label 78.94,973.674,974.154,976.933.541.980.00512.0PIPE - 09 77.84,972.804,973.654,975.364.512.490.00812.0PIPE - 10 44.14,973.434,974.404,976.093.211.150.00512.0PIPE - 17 75.64,973.234,973.434,974.983.531.910.00512.0PIPE - 18 84.04,971.494,972.814,974.435.553.260.01212.0PIPE - 11 93.04,969.474,973.234,973.507.165.620.02912.0PIPE - 19 33.74,968.424,971.494,972.579.054.150.03615.0PIPE - 12 87.14,969.474,969.844,973.504.736.470.00518.0PIPE - 06 96.64,968.424,969.474,972.575.8015.460.00524.0PIPE - 07 66.64,969.904,970.274,973.163.973.040.00515.0PIPE - 04 62.44,969.844,969.904,972.604.404.600.00518.0PIPE - 05 61.54,970.504,970.644,972.622.051.610.00512.0PIPE -13 72.54,967.804,970.504,972.587.205.660.00618.0PIPE -15 87.64,968.024,968.424,972.046.7125.610.00530.0PIPE - 08 18.84,963.644,964.364,971.9915.1926.310.04430.0PIPE - 08 (2) 88.04,967.624,967.804,971.264.976.850.00518.0PIPE -16 118.24,967.504,967.624,971.275.008.830.00518.0PIPE -16 (2) 25.54,973.434,973.644,976.092.680.640.00512.0PIPE - 26 43.24,972.934,973.174,975.361.050.37-0.0058.0PIPE - 33 0.04,971.904,971.904,973.320.000.00-0.0158.0CO-5 90.54,970.844,971.904,972.624.983.91-0.01512.0CO-6 37.74,969.234,969.524,973.332.270.320.0058.0CO-8 37.34,969.144,969.234,974.242.980.940.00512.0CO-9 59.94,968.864,969.144,972.993.351.510.00512.0CO-10 82.14,968.734,968.860.004.832.790.00912.0CO-11 70.04,969.324,969.634,974.241.710.60-0.0058.0CO-12 67.04,971.494,972.244,974.434.430.970.0148.0PIPE - 37 47.54,970.954,971.394,973.293.422.68-0.02512.0PIPE - 30 79.14,968.424,969.864,972.578.014.490.02512.0PIPE - 23 20.14,971.434,971.454,974.000.640.51-0.00512.0PIPE - 32 50.74,971.394,971.434,973.681.601.26-0.00512.0PIPE - 31 86.74,966.624,967.194,971.894.644.380.00615.0PIPE -21(STRM)(1) 85.44,966.004,966.624,970.364.704.380.00615.0PIPE -21 (STRM)(2) Page 1 of 176 Watertown Road, Suite 2D Thomaston, CT 06787 USA +1-203-755-1666 4/1/2025 StormCAD [10.04.00.158] Bentley Systems, Inc. Haestad Methods Solution CenterStormCAD-Graf-TB.stsw 100 Year Scenario: 100-Year Storm Page 1 of 176 Watertown Road, Suite 2D Thomaston, CT 06787 USA +1-203-755-1666 4/1/2025 StormCAD [10.04.00.158] Bentley Systems, Inc. Haestad Methods Solution CenterStormCAD-Graf-TB.stsw CM-15 CM-14 CM-13 CM-12 CM-11 CM-10 CM-9 CM-8 CM-7 CM-6 CM-5 CM-33 CM-32 CM-1 CM-31 CM-30 CM-29 CM-28 CM-27 CM-26 CM-24 CM-23 CM-22 CM-21 CM-20 CM-19 CM-18 CM-34 CM-17 CM-16 PIPE-15 PIPE -21 (S TRM)(1) P IP E-21 (STRM)(2 )CO-5 PIPE-33PIPE-31 PIPE-37 CO-10 PIPE-32 CO-12 PIPE-26 PIPE-04 PIPE-07 PIPE-12 PIPE-18 72.5% 20.1% 85 .4 % 86.7 % 67.0% 96.6% 66.6% 50.7% 33.7% 75.6% 70.0%59.9% 0.0% 43.2% 25.5 % 18.0in 1 5.0 in 15.0 in8.0in 8.0in12.0in 8.0in 12.0in 12.0in 8.0in 12.0 in 15.0in 24.0in 15.0in 12.0in OUTFALL 2 OUTFALL 1 O-7 O-6 O-5 CB-17 CB - 07 25 (STRM) CB - 09 CB - 28 CB-15 GI - 23 CB-14 CB - 22 YI - 21 CB-13 CB-12 MH-19 MH-18 YD-48 YD-50 YD-34 CB - 32 MH-13 CB-20 MH-14 CB - 11 MH-12 MH-8 YD - 37 CB-16 CB-39 YI - 06 CB - 10 CB-19 CB - 08 MH-21 Type II 24-hr First 0.5 Rainfall=0.50"TB-Graf St Printed 4/1/2025Prepared by Kimley-Horn & Associates HydroCAD® 10.20-5c s/n 02344 © 2023 HydroCAD Software Solutions LLC Events for Pond 2P: Detention Facility Event Inflow (cfs) Primary (cfs) Elevation (feet) Storage (cubic-feet) 2yr 5.47 0.11 2.87 13,227 5yr 8.09 0.63 3.27 15,483 10yr 9.93 1.39 3.59 17,282 25yr 12.25 2.32 4.15 20,228 50yr 13.96 2.94 4.70 22,621 100yr 15.68 3.64 5.46 25,105 First 0.5 0.70 0.04 0.48 1,488 PLAN VIEW B-BNOT TO SCALE.FIBERGLASS SEPARATIONCYLINDER AND INLETCENTER OF CDS STRUCTURE, SCREEN ANDSUMP OPENINGPVC HYDRAULIC SHEARPLATE2'-0" [610](2'-0" [610])1'-9" [533](4'-6" [1372])ELEVATION A-ANOT TO SCALE.FIBERGLASS SEPARATIONCYLINDER AND INLETSOLIDS STORAGE SUMPSEPARATIONSCREENINLET PIPE(MULTIPLE INLET PIPESMAY BE ACCOMMODATED)OUTLET PIPEPVC HYDRAULICSHEAR PLATE(4'-0" [1219])FLOWPERMANENT POOLELEV.OIL BAFFLE SKIRTCONTRACTOR TO GROUTTO FINISHED GRADEGRADERINGS/RISERSAA48" [1219] I.D. MANHOLESTRUCTURETOP SLAB ACCESS(SEE FRAME AND COVERDETAIL)VARIES +/-135°MAX.FLOW+/-65°MAX.BBFRAME AND COVER(DIAMETER VARIES)NOT TO SCALEwww.ContechES.com®800-338-1122 513-645-7000 513-645-7993 FAX9025 Centre Pointe Dr., Suite 400, West Chester, OH 45069CDS2015-4-C ONLINE CDSSTANDARD DETAILI:\COMMON\CAD\TREATMENT\22 CDS\40 STANDARD DRAWINGS\ONLINE (CDS-C)\PDF WITH TREATMENT FLOWS\DWG\CDS2015-4-C-DTL.DWG 5/7/2021 8:23 AMTHIS PRODUCT MAY BE PROTECTED BY ONE OR MORE OF THEFOLLOWING U.S. PATENTS: 5,788,848; 6,641,720; 6,511,595; 6,581,783;RELATED FOREIGN PATENTS, OR OTHER PATENTS PENDING.STRUCTURE IDWATER QUALITY FLOW RATE (CFS OR L/s)PEAK FLOW RATE (CFS OR L/s)RETURN PERIOD OF PEAK FLOW (YRS)SCREEN APERTURE (2400 OR 4700)PIPE DATA:I.E.MATERIALDIAMETERINLET PIPE 1INLET PIPE 2OUTLET PIPESITE SPECIFICDATA REQUIREMENTSWIDTHHEIGHTANTI-FLOTATION BALLASTNOTES/SPECIAL REQUIREMENTS:RIM ELEVATION* PER ENGINEER OF RECORD****************GENERAL NOTES1.CONTECH TO PROVIDE ALL MATERIALS UNLESS NOTED OTHERWISE.2.FOR SITE SPECIFIC DRAWINGS WITH DETAILED STRUCTURE DIMENSIONS AND WEIGHT, PLEASE CONTACT YOUR CONTECH ENGINEEREDSOLUTIONS LLC REPRESENTATIVE. www.ContechES.com3.CDS WATER QUALITY STRUCTURE SHALL BE IN ACCORDANCE WITH ALL DESIGN DATA AND INFORMATION CONTAINED IN THIS DRAWING.CONTRACTOR TO CONFIRM STRUCTURE MEETS REQUIREMENTS OF PROJECT.4.STRUCTURE SHALL MEET AASHTO HS20 LOAD RATING, ASSUMING EARTH COVER OF 0' - 2', AND GROUNDWATER ELEVATION AT, OR BELOW,THE OUTLET PIPE INVERT ELEVATION. ENGINEER OF RECORD TO CONFIRM ACTUAL GROUNDWATER ELEVATION. CASTINGS SHALL MEETAASHTO M306 AND BE CAST WITH THE CONTECH LOGO..5.IF REQUIRED, PVC HYDRAULIC SHEAR PLATE IS PLACED ON SHELF AT BOTTOM OF SCREEN CYLINDER. REMOVE AND REPLACE ASNECESSARY DURING MAINTENANCE CLEANING.6.CDS STRUCTURE SHALL BE PRECAST CONCRETE CONFORMING TO ASTM C-478 AND AASHTO LOAD FACTOR DESIGN METHOD.INSTALLATION NOTESA.ANY SUB-BASE, BACKFILL DEPTH, AND/OR ANTI-FLOTATION PROVISIONS ARE SITE-SPECIFIC DESIGN CONSIDERATIONS AND SHALL BESPECIFIED BY ENGINEER OF RECORD.B.CONTRACTOR TO PROVIDE EQUIPMENT WITH SUFFICIENT LIFTING AND REACH CAPACITY TO LIFT AND SET THE CDS MANHOLE STRUCTURE.C.CONTRACTOR TO INSTALL JOINT SEALANT BETWEEN ALL STRUCTURE SECTIONS AND ASSEMBLE STRUCTURE.D.CONTRACTOR TO PROVIDE, INSTALL, AND GROUT INLET AND OUTLET PIPE(S). MATCH PIPE INVERTS WITH ELEVATIONS SHOWN. ALL PIPECENTERLINES TO MATCH PIPE OPENING CENTERLINES.E.CONTRACTOR TO TAKE APPROPRIATE MEASURES TO ASSURE UNIT IS WATER TIGHT, HOLDING WATER TO FLOWLINE INVERT MINIMUM. IT ISSUGGESTED THAT ALL JOINTS BELOW PIPE INVERTS ARE GROUTED.www.contechES.comCDS2015-4-C DESIGN NOTESCDS2015-4-C RATED TREATMENT CAPACITY IS 0.7 CFS [19.8 L/s], OR PER LOCAL REGULATIONS. IF THE SITE CONDITIONS EXCEED MAXIMUM HYDRAULICCAPACITY, AN UPSTREAM BYPASS STRUCTURE IS REQUIRED.CDS2015-4-C STANDARD CONFIGURATION IS SHOWN.FOR NJDEP PROJECTS, PLEASE CONTACT YOUR LOCAL CONTECH REPRESENTATIVE FOR APPROVED CONFIGURATIONS.4974.654966.294966.29100 yr0.04 cfs4.38 cfs