Loading...
HomeMy WebLinkAboutApplication APPLICANT 8/31/2020 (2)ranch ENGINEERING= June 19, 2020 Mr. Nathan Wiedenmann Via Email nathan@stellallghting.com RE: GEOTECIiN[cAL INVFtiI1GATHYN M": 17-02-34-34 TA MAE: 700 SE GFn?r o, 0E 001197478 BRANCH EN(aNPFrsRdG hic. PROJECT No. 19-453 Branch Engineering, Inc. (BEI) has conducted a geotechnical site investigation for the proposed development located at 6185 Main Street in Springfield, Oregon On May 29, 2020 five (5) exploratory test pit excavations were advanced at the approximate locations shown on the attached Figure 1, Site Exploration Map. The accompanying report presents the results of our site research, field exploration and testing, data analyses, as well as our conclusions and recommended geotechnical design parameters for the project Based on the results of our study, no geotechnical/geologic hazards were identified at the site that would prohibit the proposed apartment building and the site is suitable for the planned development, provided that the recommendations of this report are implemented in the design and construction of the project. Sincerely, Branch Engineering Inc. EXPIRES: 12/31/2021 Ronald Derrick P.E., G.E. Principal Geotechnical Engineer I' Digitally signed by Ronald J. Derrick cK Date: 2020.06.1910:34:47-07'00' EUGENE -SPRINGFIELD ALBANY-SALEM-CORVALLIS p. 541.]46.063] 1 w .branchengineering.com Arrowhead Meadows Development Springfield, Oregon TABLE OF CONTENTS 1.0 INTRODUCTION............................................................................................................... 3 1.1 Purpose and Scope of Work 3 1.2 Project Location and Description 3 1.3 Site Information Resources 3 2.0 SITE SUBSURFACE CONDITIONS 2.1 Subsurface Soils 2.2 Groundwater 3.0 GEOLOGIC SETTING.......................................................................................................5 3.1 Regional Geology 5 3.2 Site Geology 6 4.0 CONCLUSIONS..................................................................................................................6 5.0 RECOMMENDATIONS....................................................................................................6 5.1 Site Preparation and Foundation Subgrade Requirements 7 5.2 Engineered Fill Recommendations 8 5.3 Excavations 9 5.4 Drainage 9 5.5 Soil Bearing Capacity 9 5.6 Settlement 10 5.7 Slabs on Grade 10 5.8 Soil Shrink/Swell Potential 10 5.9 Friction Coefficient and Earth Pressures 10 5.10 Wet Weather/Dry Weather Construction Practices 11 5.11 Pavement Design Recommendations 11 5.12 Seismic Site Classification and Hazards 12 6.0 LIMITATIONS 13 FIGURE -1 - Site Exploration Map APPENDIX A- USCS Exploratory Key, Test Pit Summaries, Well Logs, NRCS Soil Survey Information APPENDIX B- Recommended Earthwork Specifications Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon 1.0 INTRODUCTION 1.1 Purpose and Scope of Work The purpose of this work is to present our subsurface findings and provide geotechnical engineering recommendations that may influence the design and construction of the proposed project. Our field investigation scope of work consisted of a site reconnaissance and subsurface investigation on May 29, 2020. A Kubota Tractor Wheel Loader Backhoe equipped with a 1.5 -foot wide bucket was used to excavate five (5) test pits on the site to a maximum depth of 6.5 -feet below ground surface (BGS), the soils exposed in the test pits were then visually classified by the Unified Soil Classification System (USCS), and the test pits were backfilled See the attached Figure -1, Site Exploration Map, for test pit excavation locations. Our work scope also included pertinent site research activities, field and laboratory testing, engineering data review, analysis, and preparation of this Report. 1.2 Project Location and Description The subject site is located at the approximate project coordinates of 44.045032° north and 122.9194380 west in Springfield, Oregon. The site currently consists of one Tax Lot, approximately 1.0 -acres in size. A single-family residence had been demolished on the north end of the site and some debris and utilities from the demolition were visible. The site topography is relatively fiat from Main street south to Aster Street before north facing slopes of approximately 30 - to 50% are met on the south side of the property. Site vegetation is mown grass on the flat portion dense Himalayan blackberry, deciduous, and evergreen trees on the north facing hillslope. Towards the center of the parcel a culvert and stormwater channel exist. Wetland delineation performed by BEI (report dated to November, 2019) determined the presence of wetlands on the site. The site is bordered by the Mountain Gate Subdivision to the south, Main Street/Highway 126 to the north, and residential lots on the east and west. The proposed development will consist of two multi -unit apartment buildings with ground level parking/storage on the northern portion of the parcel and a single multi -unit townhouse building on the hillslope portion of the parcel. A public right-of-way extension of Aster Street traverse the site with a 20 -foot -wide private drive isle, associated parking, concrete walkways, public and private utilities, and landscaping as part of the project. Specific structural loads were not provided; however, wood -framed, 2- to 3 -story apartment buildings typically do not exceed 20 -kip column loads or 2-kip/If line loads on foundations. 1.3 Site Information Resources The following site investigation activities were performed and literature resources were reviewed for pertinent site information • Five (5) exploratory test pits excavated to a maximum depth of 6.5 feet BGS on May 29, 2020 at the approximate locations shown on the attached Figure -1 Site Exploration Map. See attached test pit log summaries in Appendix A - Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon • Review of the Web Soil Survey of Lane County Area, United States Department of Agricultural (USDA) Natural Resources Conservation Service (NRCS) (attached in Appendix A) • Review of USGS Geologic Map of Oregon, Walker and MacLeod, 1991 and review of the 2010 Oregon Department of Geology and Mineral Industries (DOGAMI) Geologic Map Open File Report 0-10-03 Digital Geologic Map of the Southern Willamette Valley by Jason D. McClaughry, Thomas J. Wiley, Mark L Ferns, and Ian P. Madin. • Review of previous work by BEI in the vicinity of the site. • Oregon Department of Geology and Mineral Industries (DOGAMI) web hazard viewer. • Review of Oregon Department of Water Resources Well Logs (attached in Appendix A). • Oregon Structural Specialty Code 2019 (OSSC 2019), applicable building code criteria • Geology of Oregon, sixth edition by On, Orr and Baldwin, 2012. 2.0 SITE SUBSURFACE CONDITIONS 2.1 Subsurface Soils The analyses, conclusions, and recommendations contained in this report are based on site conditions as they presently exist and assume the exploratory results presented in Appendix A are representative of the subsurface conditions throughout the site. If, during construction, subsurface conditions differ from those encountered in the exploratory test pits; BEI requests that we be informed to review the site conditions and adjust our recommendations if necessary. Visual classification of the near surface soils was performed in accordance with the American Society of Testing and Materials (ASTM) Method D-2488 and the Unified Soil Classification System (USCS). The site subsurface soils varied throughout the site and can generally be split into three areas, a north (TP -1 & TP -2), central (TP -3), and southern portion (TP -4 & TP -5). In Test Pits 1 and 2, soil profiles consist of alluvial silty clays and clayey silts overlying sandy gravel, which was found at 3.5 -feet and 5.5 -feet below ground surface (BGS) in TP -1 and TP -2 respectively. ffi1 consisting of pottery, bone, organics, and bricks was found in TP -2 to a depth of 3.5 -feet BGS. Based on the located to the south of the demolished residence, it is likely a buried debris pile and may be isolated to area in which the test pit was dug. Test Pit 3 soil profile consists of colluvial, high plasticity gray clay extending from near surface to approximately 3.25 -feet BGS, alluvial sandy gravel was found at 4.5 -feet BGS. Test pit 4, excavated at the base of the north facing hillslope and Test Pit 5 excavated on the hillslope had similar soil profiles consisting of colluvial clayey silt with angular to subangular basalt which ranged from cobble to boulder size. Test Pits were terminated due to equipment refusal on either alluvial sandy gravel of basalt boulders. The USDA NRCS Web Soil of Lane County Area maps three soil units present on the site; Coburg - Urban land complex (Soil Number 32), Courtney silty clay loam (Soil Number 2224A) and Nelda silty clay loam, 30-50% slopes (Soil Number 89F) are the soil types across the site from north to south respectively. Coburg -urban land complex is described as stream terrace deposits derived Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon from a parent material of loamy alluvium over clayey alluvium. Courtney gravelly silty clay loam is described as drainageway stream terrace deposits derived from a parent material of alluvium. Nekia silty clay loam, mapped on the hillslopes is described as hillslope soil derived from a parent material of basalt/tuff colluvium and residuum. The above listed soil descriptions are consistent with observations made by BEI in test pit excavations. 2.2 Groundwater No groundwater was encountered during the site exploration We expect that ground water levels (from the regional water table or perched lenses) will fluctuate with the seasons and should be expected to be highest during the late winter and spring months when rainstorms are more intense and frequent, and soils are near saturation. Well logs from nearby sites, obtained from the Oregon Department of Water Resources' online database were reviewed and static water levels were listed between 8- and 1S -feet BGS in sandy gravel alluvium. The vertical hydraulic conductivity of the gray clay may cause formation of perched water lenses during periods of extended precipitation. 3.0 GEOIDGIC SETTING The following sections describe the regional and local site geology. Our field findings are consistent with the geologic mapping of the site area by the Oregon Department of Geology and Mineral Industries Open File Report (OFR) 0-10-03 Digital Geologic Map of the Southern Willamette Valley. 3.1 Regional Geology The subject site lies within the southern portion of the Willamette Valley, east of the Coast Range and west of the Cascade Mountains Provinces. In Oregon the Willamette Valley is an elongate basin which narrows at both ends before terminating in the Calapooya Divide to the south and the Columbia River to the north. The basin is approximately 130 miles long and 40 miles wide. The valley is drained by the Willamette River and drops from an elevation of approximately 400 -feet at Eugene, to near sea level at the northern end of the basin where the Willamette River drains into the Columbia River. The Willamette River Valley in the area of the subject site is believed to be underlain by undifferentiated sedimentary rock, tuffs and basalt from the Miocene and Oligocene epochs (approximately 15 to 35 million years ago). Deposits of silt and clay from fluvial and lacustrine environments covered the bedrock to various depths during the presence of low energy streams and lakes in the mid -Willamette Valley. Subsequent compression forces and uplifting of the Cascade and Coast Range Mountains depressed the Willamette River Valley. The rapid uplift of the Cascade and Coast Range mountains steepened stream gradients causing increased erosion of the mountains and resulting deposition of thick gravel layers incised within the fluvial and lacustrine deposits. During the last deglaciation and the resulting termination of the Idst Glacial Maximum in North America, the Willamette Valley was cyclically flooded by catastrophic breaks in the ice dams of Glacial [Ake Missoula. Occurring several times over an approximately 2,000 -year period between Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon 13,000 to 15,000 ago these flood even filled the valley to an elevation of 350- to 400 -feet before retreating, causing sequences of upward fining deposits of silt and clay that may or may not still be present in areas depending on erosion by subsequent fluvial actions. (On and On, 2012). 3.2 Site Geology The OFR 0-10-03 2010 DOGAMI Digital Geologic Map of the southern Willamette Valley maps the site geology on the boundary between Quaternary age Terrace and Fan Deposits (Qtf) and lower Miocene to middle Focene aged Early Western Cascades Lava (Twd). The formation (Qtf) which is described as deeply dissected unconsolidated to semi -consolidated deposits of gravel, sand, silt, and clay that form upper alluvial terraces along the Willamette River, and other rivers and tributary streams draining the Cascade and Coast Range Mountains is consistent with field findings in the relativity flat portion of the site. Twcl which is described as basalt and basaltic andesite, andesite, and dacite lavas that are part of the Eocene Eugene Formation and the upper Eocene to lower Miocene Little Butte Volcanics. These lavas are typically discontinuous and have complex contact relationships with coeval volcaniclastic rocks. These rocks are characterized by low permeability, low porosity, and low well yields. The above geologic descriptions are consistent with our field findings. 4.0 CONCLUSIONS Based on our field observations, subsurface explorations, and data analyses, we conclude that the site is geologic and geotechnically suitable for the proposed development provided that the recommendations of this report are incorporated into the design and construction of the project. Our investigation did not reveal any specific site features or subsurface conditions that would impede the proposed design and construction of the project. 5.0 RECOMMENDATIONS Based on our field observations and research we conclude that the site is suitable for construction provided that the following recommendations are incorporated into the design and construction of the proposed development. Our investigation did reveal subsurface conditions that should be studied and incorporated into site development plans. • The clay soil underlying topsoil in the central portion of the site has high shrink/swell characteristics. The recommendations described below are intended to mitigate potential for the proposed structures to experience settlement beyond tolerable limits and damage from expansive soil issues. General material and construction specifications for the items discussed herein are provided in Appendix B. Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon 3.1 Site Preparation and Foundation Subgrade Requirements The following recommendations are for earthwork in the building foundation areas and parking areas. Earthwork shall be performed in general accordance with the standard of practice as generally described in Appendix J of the 2019 Oregon Structural Specialty Code and as specified in this report. All areas intended to directly or laterally support structures, roadways, or pavement areas shall be stripped of vegetation, organic soil, unsuitable fill, and/or other deleterious material such as moisture softened exposed soil. These stripping's shall be removed from the site or reserved for use in landscaping or non-structural areas. In areas of existing trees, vegetation, or previously placed fill the required depth of site clearing/stripping may be increased. The subsurface conditions observed in our site investigation test nit excavations are consistent however. the test pits only represent a very small portion of the site. Should soft or unsuitable soils extend to a depth greater than that described herein, or areas of distinct soli variation be discovered this office shall be notified to perform site observation and additional excavation may be reouired. Building Foundation Subgrade Preparation Within the area of the proposed building foundations we recommend that all organic soil, soft, or wet material be removed from structural areas. Areas of existing trees may require an increased depth of excavation to completely remove roots and organic material. The depth to suitable subgrade for foundations varied across the site. To provide site specific foundation requirements the areas will be described separately below. Zone 1, /Yom Main Street to approximately 150 -Peet south Suitable subgrade consisting of medium stiff, brown clayey silt is below the topsoil zone and any fill or debris from the demolished residence, usually encountered within 18 inches of the ground surface. Areas of undocumented fill (organic and on -organic debris) may be encountered and will require complete removal. Zone 2, FYom 150¢'eet south or Main Street to Aster Street. Suitable subgrade consisting of gray -brown sandy clay and dense sandy gravel is below the colluvial high plasticity, gray clay, and can be expected to be encountered between 3- and 3. S -feet BGS. Zone 3, FYom Aster Street to the southern property boundary. Suitable subgrade consisting of brown colluvial clayey silt can expected below the topsoil zone at depth of 12- to 18 -inches BGS. Upon excavation to suitable subgrade we recommend that compacted aggregate, a minimum of 12 -inches in thickness be placed on the subgrade soil within the building foundation areas. If areas of soft soil, saturated soil, or plastic clay are encountered during building pad excavation we recommend that the depth of excavation and thickness of compacted be increased at the direction of the geotechnical engineer of record or designated representative. The placement of the Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon compacted aggregate shall extend horizontally a minimum of 12 -inches outside of foundation footings. Guidelines for engineered fill placement are found below in Section 5.2, the compacted aggregate specified to be placed under foundations shall be placed in accordance with the criteria in Section 5.2. Prior to the placement of compacted aggregate, the Geotechnical Engineer, or designated representative shall visit the site to confirm the suitabilityof the subgrade material and excavation. Pavement Area Subgrade Preparation In pavement areas, topsoil, and any organics shall be removed to a depth of approximately 1S - inches BGS. Prior to the placement of separation fabric and compacted aggregate base rock in pavement areas we recommend that the geotechnical engineer, or designated representative visit the site to approve the subgrade. If areas of soft soil are observed we recommend over -excavation and replacement with compacted aggregate. We recommend that pavement areas be excavated to suitable subgrade elevations and proof rolled with a loaded 10 CY haul truck, if areas of significant deflection or 'pumping' under wheel loads are observed over -excavation of the soil and replacement with compacted aggregate fill may be required. Recommendations for base rock thickness, compaction and AC thickness are presented below in Section S.11. Construction Observations Periodic site observations by a geotechnical representative of BEI are recommended during the construction of the project; the specific phases of construction that should be observed are shown in Table 1 below: Table 1: Recommended Construction Phases to be Observed by the Geotechnical Engineer At completion of subgrade excavation Subgrade observation by the geotechnical engineer before fabric and aggregate placement. Imported fill material Observation of material or information on material type and source. Placement or Compaction of fill material Observation by geotechnical engineer or test results by qualified testing agency. 5.2 Structural Fill Recommendations All engineered fill placed on the site shall consist of homogenous material and shall meet the following recommendations. Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon • Prior to placement on-site the aggregate to be used as structural fill shall be approved by the geotechnical engineer of record, if no Proctor curve (moisture -density relationship) for the material performed within the last 12 -months is on file a sample may be required to perform testing to determine the maximum dry density and optimum moisture content of the aggregate. • The structural fill shall be moisture conditioned within +/- 2% of optimum moisture content and compacted in lifts with loose lift thickness not exceeding 8 -inches. • Periodic visits to the site to verity lift thickness, source material, and compaction efforts shall be conducted by the Geotechnical Engineer or designated representative and documented. • The recommended compaction level for crushed aggregate fill is 9096 relative compaction as determined by ASTM D-1557 (modified Proctor). Compaction shall be measured by testing with nuclear densometer ASTM D-6938, or D-1556 sand cone method on structural fill in excess of 12 -inches in thickness. • If on-site material is approved for fill placement a sample of the material shall be collected for a modified Proctor test be conducted and used for compaction testing. If, due to the nature of the on-site material compaction testing is not possible due to factors as oversize rock content and variable material, proof rolls with a fully loaded 10 CY haul truck shall be observed at regular intervals. Observed areas of soft soli will require over -excavation and replacement with suitable material. 5.3 Excavations We expect excavations into the medium stiff clayey silt material will stand near -vertical to depths of at least 4 feet BGS; however, sidewall seepage may occur during the wet season. After removal of any near -surface loose material excavation into the fine grain soli may be classified as OSHA Type A; however, if groundwater seepage is encountered in the excavations, the OSHA classification shall be Type C. Heavy equipment nor materials should not be parked or stored within 10 feet of open excavations. 5.4 Drainage A site drainage system is expected to be required for this project. Alteration of existing grades for this project will likely change drainage patterns, but should not adversely affect adjacent properties. Perimeter landscape and hardscape grades shall be sloped away from the foundations and water shall not be allowed to pond adjacent to footings during or after construction. We recommend all structures built on or at the foot of the north facing hillslope be constructed with footing drains. 5.5 Soli Bearing Capacity Conventional perimeter style foundations and spread footings for column loads are suitable for the proposed building construction and we recommend that loads are distributed evenly to mitigate the potential for differential settlement. If foundation areas are prepared as described in Branch Engineering, Inc. Arrowhead Meadows Development Spnngfield, Oregon Section S.1 of this report, the allowable bearing capacity is 1, 800 pad and may be increased by 1/3 for short term loading such as wind or seismic events. 5.6 Settlement After preparation of the foundation subgrade as described in Section S.1 the total and differential settlement of the structure after completion is not expected to exceed %-inch or 7i -inch, respectively, between equivalently loaded footings. Loads should be distributed as evenly as possible to limit differential settlement and buildings shall not be above transitions between cut and structural fill. 5.7 Slabs -On -Grade We recommend that the subgrade preparation for load bearing slabs be treated similarly to the building foundation preparation due to the expansive nature of the subgrade soil underlying the site and potential settlement. Slabs should be frilly reinforced and concrete panels structurally connected to each other to limit differential settlement, or seasonal shrink/swell movement The modulus of subgrade reaction of the underlying native clayey silt soil is 90 lb/in', with 18 -inches of compacted aggregate the modulus of subgrade reaction is 120 lb/in'. Non -load bearing slabs shall be sufficiently supported to mitigate settlement and cracking from underlying soil conditions. 3.8 In -Situ Moisture Content & Soil Shrink/Swell Potential Samples of the site soil were collected for in-house in-situ moisture content and Free Swell (13 2720) testing. In-situ moisture content of the soil ranged from 40.3% to 43.496 with moisture content typically increasing with depth in the test pits. Free Swell Testing results ranged from 4096 in the clayey silt soil to 10096shrink/swell potential in the gray clay. These values are considered moderate to high shrink/swell potential. 5.9 Friction Coeffide at and Earth Pressures For use in design of subsurface structures or retaining walls the following parameters are given based on an internal angle of friction of 22° for the day and clayey silt material in the flat portion of the site. The coefficient of friction for concrete poured neat against undisturbed native soil is 0.27 and if poured atop a minimum thickness of 12 -inches of compacted aggregate placed on the on-site material the coefficient is 0.4. Table 2: Earth pressures and Friction Coefficient Active Earth Pressure 45 pcf Passive Earth Pressure 220 pcf Lateral Earth Pressure (at Rest) 66 pcf Coefficient of Friction 0.27 Values assume there is no hydrostatic pressure or surcharge loads on the structures. Branch Engineering, Inc. 10 Arrowhead Meadows Development Spnngfield, Oregon For subsurface structures or retaining walls constructed on the north facing hillslope the following parameters are given based on an internal angle of friction of 30°. The coefficient of friction for concrete poured neat against undisturbed native soil is 0.38 and if poured atop a minimum thickness of 12 -inches of compacted aggregate placed on the on-site material the coefficient is 0.4. Table 3: Earth pressures and Friction Coefficient Active Earth Pressure 33 pcf Passive Earth Pressme 300 pcf Lateral Earth Pressure (at Rest) SO pcf Coefficient of Friction 0.38 Values assume there is no hydrostatic pressure or surcharge loads on the structures. Excavations for retaining wall structures should be performed in manner that minimizes disturbance to the slope to minimize sloughing and sliding of material. This can be accomplished by constructing limited segments of the wall at a time. Critical to long-term management of retaining wall structures will be the management of drainage, footing drains are recommended for all structures built into the hillslope. 3.10 Wet Weather/Dry Weather Construction Practices The site material is moisture sensitive and will soften with exposure to precipitation. The near surface silty clay material, if left exposed to the prolonged precipitation it will soften and saturate. Subgrade soil that will be below foundations, slabs, and pavement shall be covered with compacted aggregate in a timely manner after excavation to minimize moisture fluctuations. BELrecommends that foundation subgrade preparation and general site earthwork be performed during the dry season, generally May through October. Construction during the wet season may require special drainage considerations, such as covering of excavations, pumping to mitigate standing water in footing excavations, or over -excavation of moisture softened soils. 3.11 Pavement Design Recommendations Following the removal of any topsoil or unsuitable subgrade material such soft material or organics the underlying subgrade soil is suitable for the placement of a pavement structural section consisting of Asphalt Concrete (AC) placed on compacted base rock. Our recommendations for any parking or driveway improvements used a CBR of 3 to 4 and the guidance of the 1993 AASHTO Guide for Design of Pavement Structures and 2003 revised Asphalt Pavement Design Guide, published by the Asphalt Pavement Association of Oregon. For new AC pavement installation, we recommend a separation fabric be laid on the prepared subgrade surface. In parking areas and light vehicle routes, we recommend a minimum pavement thickness of 3 -inches of AC over a minimum of 12 -inches of compacted base rock We recommend that the AC thickness be increased to 4 -inches in areas of heavier traffic, such as refuse truck routes or delivery vehicles. A minimum of 5.5 -inches of Portland Cement Concrete (PCC) with a minimum modulus of rupture of 600 psi over 6 -inches of compacted base rock is recommended Branch Engineering, Inc. 11 Arrowhead Meadows Development Spnngfield, Oregon for rigid PCC pavement. Prior to placement of base rock any soft soil, wet soil, or organic Boll shall be removed from the pavement subgrade. The geotechnical engineer of record, or designated represents five should visit the site to approve the subgrade soil prior to the placement of the base rock. Proof rolls with a loaded 10 CY haul truck shall be observed on the compacted base rock prior to pavement installation and any areas of deflection under wheel loads shall be corrected by over -excavation replacing subgrade material with additional compacted aggregate. The base rock shall be compacted to at least 95% relative compaction as determined by ASTM 1557/AASHTO T-180 (modified Proctor). The base rock shall be tested to measure compliance with this compaction standard prior to placement of asphalt concrete. The above recommended structural pavement sections are designed for the type of vehicle use on the site after construction completion, not for construction vehicle traffic which is generally heavier, occurs over a short time, and impacts the site before full pavement sections are constructed. The construction traffic may cause subgrade failures and the site contractor should consider over -building designated haul routes through the site to mitigate soft areas at the time of final paving. 5.12 Seismic Site Classification and Hazards Based on the soil properties encountered in our site pits and on-site well log information a Seismic Site Class D designation, stiff Boll (Table 20.3-1 ASCE 7) is recommended for design of site structures. OSSC 2014 (1803.5.11) required criteria for hazards the geotechnical investigation shall address for seismic site class designations C through F are listed below. Slope Instability: The northern portion of the site is mapped low risk for land sliding, while the north facing hillslope is mapped as moderate to high risk of landsliding. Mapped landslides are numerous in the area, occurring within a quarter mile to the east and west off the site. Soil observed on the southern 3/4- of the site is derived via colluvial action from the north facing hillslope. Test Pits 4 and 5, excavated at the foot and on the hillslope uncovered angular basalt consistent with material derived from massive basalt formations near the crest of the hill. Landslide risks and hazards may be mitigated following recommendations included in this report. Liquefaction: The subsurface soil contains some fine grain sand however, the Boll also has clay and silt mixed with the fine grain sand, is medium stiff in consistency and unlikely to become saturated at the depths of the fine grain sand the risk of liquefaction on the site is low. Total and Differential Settlement: The estimated amount of total and differential settlement is less than 3/4 inch and 1/2 inch, provided subgrade preparation follows the recommendations in Section 5.1 of this report. Surface Displacement due to faulting or seismically induced lateral spreading or lateral flow: No faults are present on the site that could create surface displacement, seismically induced lateral spreading is not expected due to the relatively flat site topography. The nearest mapped faults are approximately 2.5 miles to the southwest, and 3.6 -miles to the north of the site. Although infrequent, earthquakes do occur in the area, specifically near the Coburg Hills (PNSN) and seismic activity of significance has been felt in the greater area as evidenced by the 1993, 5.7 Richter magnitude Scotts Mills earthquake near Salem and the 2015, 4.2 Richter magnitude earthquake Branch Engineering, Inc. 12 Arrowhead Meadows Development Spnngfield, Oregon 12 -miles east of Eugene. Seismic experts predict the reoccurrence of a Cascadia Subduction Zone (CSZ) earthquake every 250- to 500 -years capable of producing a Richter magnitude 9.0 event off the coast of Oregon. The last CSZ event was about 300 years ago. 0.0 REPORT I.IMIEATIONS This report has presented REI's site observations and research, subsurface explorations, geotechnical engineering analyses, and recommendations for the proposed site development. The conclusions in this report are based on the conditions described in this report and are intended for the exclusive use of Nathan Wiedenmann and his designated representatives for use in design and construction of the development described herein The analysis and recommendations may not be suitable for other structures or purposes. Services performed by the geotechnical engineer for this project have been conducted with the level of care and skill exercised by other current geotechnical professionals in this area. No warranty is herein expressed or implied. The conclusions in this report are based on the site conditions as they currently exist and it is assumed that the limited site locations that were physically investigated generally represent the subsurface conditions at the site. Should site development or site conditions change, or if a substantial amount of time goes by between our site investigation and site development, we reserve the right to review this report for its applicability. If you have any questions regarding the contents of this report please contact our office. Branch Engineering, Inc. 13 LEGEND21 25 TP -1 1NDICATES APPROXIMATE LOCATION OF EXPLORATORY TEST PIT Danch S TE EXPLORATION MAP - ARROWHEAD MEADOWS DEVELOPMENT FIGURE -1 ENG IN E E R I N G-- MAP: 17-02-34-34 TAX LOT: 700 SPRINGFIELD, OREGON 51.,19; 310 5th STREET, SPRINGFIELD, OREGON 97477 DATE 06/15/2020 JSOIi4B@[QLdLY' APPENDIX A Test Pit Log Summaries, Well Logs, and NRCS Soil Survey RELATIVE DENSITY - COARSE GRAINED SOILS USCS GRAIN SIZE RELATIVE SPT N -VALUE D&M SAMPLER D&M SAMPLER FINES <#200(.075 mm) DENSITY (140 lbs hammer) (300 lbs hammer) SAND Fine #200- #40(.425 mm) Medium #40-#10(2 mm) VERY LOOSE <4 <11 <4 Coarse #10-#4(4.75 mm) LOOSE 4-10 11-26 4-10 GRAVEL Fine #4-0.75 inch MEDIUM DENSE 10-30 26-74 10-30 Coarse 0.75-3 inch DENSE 30-50 74-120 30-47 COBBLES 3-12 inches VERY DENSE >so >120 >47 CONSISTENCY - FINE GRAINED SOILS CONSISTENCY SPT N -VALUE D&M SAMPLER D&M SAMPLER POCKET PEN./ MANUAL PENETRATION TEST (140 lbs hammer) (300 lbs hammer) UNCONFINED (TSF) VERY SOFT <2 <3 <2 <0.25 Easy several inches by fist SOFT 2-4 3-6 2-5 0.25-0.51 Easy several inches by thumb MEDIUM STIFF 4-8 6-12 5-9 0.50-1.00 Moderate several inches by thumb STIFF 8-15 12-25 9-19 1.00-2.00 Readily indented by thumb VERY STIFF 15-30 25-65 19-31 2.00-4.00 Readily indented by thumbnail HARD >30 >65 >31 >4.00 Difficult by thumbnail UNIFIED SOIL CLASSIFICATION CHART MAJOR DIVISIONS GROUP SYMBOLS AND TYPICAL NAMES GRAVELS: 50% CLEAN GW Well -graded gravels and gravel -sand mixtures, little or no fines. COARSE- or more GRAVELS GP Poorly -graded gravels and gravel -sand mbdures, little or no fines. GRAINED retained on GRAVELS WITH GM Silty gravels, gravel -sand -silt mixtures. SOILS: More than the No.4 sieve FINES GC Clayey gravels, grovel -sand -clay mbdures. 50% retained SANDS: 50% or CLEAN SANDS SW Well -graded sands and gravely sands, little or no fines. SP Poorly -graded sands and gravelly sands, little or no fines. on No. 200 sieve more passing the No.4 sieve SANDS WITH SM Silty sands, sand -silt mbdures. SC Clayey sands, sand -clay mixtures. FINES FINE-GRAINED ML Inorganic silts, rock flour, clayey silts. SOILS: LIQUID LIMIT CL Inorganic clays of low to medium plasticity, lean clays. Less than LESS THAN 50 OL Organic silt and organic silty clays of low plasticity. 50% retained SILT AND CLAY MH Inorganic silk, clayey silk. on No. 200 LIQUID LIMIT 50 CH Inorganic clays of high plasticity, fat clays. sieve OR GREATER OH Organic clays of metlium To high plasticity. HIGHLY ORGANIC SOILS PT Peat, muck, and other highly organic soil. MOISTURE CONTENT STRUCTURE DRY: Absence of moisture, dusty, dry to the touch STRATIFIED: Altemafing layers of material or color> 6mm thick DAMP: Some moisture but leaves no moisture on hand IAMINATED: Alternating layers <6mm thick. MOIST: Leaves moisture on hand FISSURED: Breaks along definate fracture planes. WET: Visble free water, usually saturated SLICKENSIDED: Striated, polished or glossy fracture planes. BLOCKY: Cohesive soil that can be broken down into small PLASTICITY DRY STRENGTH DIUTANCY TOUGHNESS angular lumps which resist further breakdown. ML Non to Low Non to Low Slow to Rapid Low, can't roll LENSES: Has small packets of different soils, note thickness. CL Low to Med. Med. to High None to Slow Medium MH Med. to High Low to Med. None to Slow Low to Med. HOMOGENEOUS: Some calor and appearance throughout. CH Med. to High High to V.High None High LIST OF ABBREVIATION & EXPLANATIONS SPT Standard Penetration Test split barrel sampler G Grab sample D&M Dames and Moore sampler MC Moisture Content LL Atterberg Liquid Umit MD Moisture Density PL Atterberg Plastic Limit UC Unconfined Compressive Strength PP Pocket Penetrometer VS Vane Shear EXPLORATORY KEY anch GINEERING_ 310 5th Street Springfield OR 97477 1 p: 541.746.0637 1 w .branchengineeringxdrn anch TEST PIT ID: TP -1 g GlNffklNG_ Sheet1of1 Client: Nathan Wiedenmann Project Name: Anonwhead Meador Development Project Number. 19-453 Project Location: Springfield, Oregon Date Started: May 292020 Completed: May292020 Logged By: SPR Checked By: RID Drilling Contractor. Branch Engineering Inc. Latitude: Longitude: Elevation: DrillingMethod: Test Pb Excavation Ground Water levels Equipment: Mini-E.vator Q Hammer Type: Z Notes: C1 SPT N -Value ffi c MC:® oo. 3 u PL 1-14. 0-1 @ Material Description E y�qo 5¢ m C 1p yqj uz p dc LL 10 m W 4050 6070 80 sa I'd 3� 40 W Ba 7a as sa Dark Brown Clayey SILT (OH), Soft to Medium Stiff. Topsoil Zone. 1 Brown Clayey SILT (ML), Medium Stiff, Moist. Slight OXidation 2 Staining. 3 4 Sandy GRAVEL (GM), Moist to Wet, Dense. 5 6 7 8 9 -- 011 10- 11- 12 13 14 15 16 17 18 19 20 21 22 324 23- 24- 25 26 27 28 29 30 31- 32 Plot Legend: A SPIN -Value Q Rnes Content a Massure Content H %aseo Unnit and liquid omit anch TEST PIT ID: TP -2 g GlNffklNG_ Sheet1of1 Client: Nathan Wiedenmann Project Name: ArmoAhead Meadows Development Project Number. 19-453 Project Location: Springfield, Oregon Date Started: May 292020 Completed: May292020 Logged By: SPR Checked By: RID Drilling Contractor. Branch Engineering Inc. Latitude: Longitude: Elevation: DrillingMMhod: Test Pk Excavation Ground Water levels Equipment: Mini -Excavator Q Hammer Type: Z Notes: C1 SPT N -Value ffi c MC:® ' 3 u PLLL♦111 y @ Material Description m m C 7 r u Z dc 10 m 00 40 50 80 70 as sa I'd 50 4'0 W 80 7a as sa Mottled Brown -Gray Clayey SILT (ML). Suspected Fill, Debris 1 Consisting of Brick, Ceramics, Bone, and Organics. Moist, 2 Medium Stiff. 3 4 Mottled Brown Gmy Clayey SAND (SC), Stiff, Moist. Slight Oxidation Staining. 5 6 Sand GRAVELGM, Moist, Dense. 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 324 23- 24- 25 627 26- 27- 28 29 30 31- 32 Plot Legend: A SPIN -Value Q Rnes Cannot a Massure Canrent H %as& Dark and liquid Dark anch TEST PIT ID: TP3 g GlNffklNG_ Sheet1of1 Clleet: Nathan Wiedenmann Project Name: Arrowhead Meadcwn Development Project Number. 19-453 Project Location: Springfield, Oregon Date Started: May 292020 Completed: May292020 Logged By: SPR Checked By: RID Drilling Contractor. Branch Engineering Inc. Latitude: Longtude: Elevation: DrillingMethod: Test Pb Excavation Ground Water levels Equipment: Mini -Excavator Q Hammer Type: Z Notes: C1 SPT N -Value ffi c MC:® oo. 3 u PL 1-14. 0-1 @ Material Description E y�qo 5¢ m C 1p yqj u z p dc LL 10 m 30 40 50 60 70 80 sa I'd 3� 40 W Ba 7a as sa Dark Brown Clayey SILT (OH), Soft to Medium Stiff. Topsoil Zone. Gray Colluvial CLAY (CH), Medium Stiff to Stiff, Moist to Wet, High 1 2 Plasticity. 3 Mottled Gray -Brown Sandy CLAY (SQ, Stiff, Moist, Slight 4 Oxidation Staining. Sandy GRAVEL(GM), Moist to Wet, Dense. 5 6 7 8 9 -- 011 10- 11- 12 13 14 15 16 17 18 19 20 21 22 324 23- 24- 25 627 26- 27- 28 29 30 31- 32 Plot Legend: A SPIN -Value Q Rnes Canrent a Massure Canrent H %aseo Unnit and liquid emir anch TEST PIT ID: TP -4 g GlNffklNg_ Sheet1of1 Client: Nathan Wiedenmann Project Name: Anonwhead Meadows Development Project Number. 19-453 Project Location: Springfield, Oregon Date Started: May 292020 Completed: May292020 Logged By: SPR Checked By: RID Drilling Contractor. Branch Engineering Inc. Latitude: Longitude: Elevation: DrillingMMhod: Test Pk Excavation Ground Water levels Equipment: Mini -Excavator Q Hammer Type: Z Notes: C1 SPT N -Value ffi c MC:® ' 3 u PLLL♦111 y @ Material Description m m C 7 r u Z dc 10 m 00 40 50 80 70 as sa I'd 50 4'0 W 80 7a as sa Dark Brown Colluvial Clayey SILT (OH), Medium Stiff, Moist, 1 Scattered Angular Basalt Rocks. 2 3 Brown Colluvial Clayey SILT (ML), Medium Stiff to Stiff, Moist. Scattered Basalt Rocks. 4- 5- 56 6 7 8 9 10 11 12 13 14 S1615- 16- 17 18 920 19- 20- 21 22 324 23- 24- 29 627 26- 27- 28 29 30 31- 32 Plot Legend: A SPIN -Value Q Fines Content a Massure Content H %aseo Dark and liquid Dark anch TEST PIT ID: TP -5 g GlNffklNg_ Sheet1of1 Cllecd: Nathan Wiedenmann Project Name: Arrowhead Meadows Development Project Number. 19-453 Project Location: Springfield, Oregon Date Started: May 292020 Completed: May292020 Logged By: SPR Checked By: RID Drilling Contractor. Branch Engineering Inc. Latitude: Longitude: Elevation: DrillingMMhod: Test Pk Excavation Ground Water levels Equlpmenl: Mini -Excavator Q Hammer Type: Z Notes: C1 SPT N -Value ffi c MC:® oo. 3 u PL 1-14. 0-111 y @ Material Description E y�qo 5 ¢ --2 C 7 r u Z dc 10 m 00 40 50 80 70 as sa I'd 50 4'0 W 80 7a as sa Brown Colluvial Clayey SILT (ML), Stiff, Moist, Large Angular 1 Basalt Pieces Increasing in Size and Density with Depth. 2 3 4- 5 6 7 8 9 10 11 12 13 14 15- 16 17 18 920 19- 20- 21 22 23 24 25 627 26- 27- 28 29 30- 31 32 Plot Legend: A SPTN-Value Q Rnes Content a Massure Content H %aseo Dark and liquid Dark *anch N G I NEE RING DYNAMIC VANE LOG DEPTH BLOWS PER10cm PROJECT NUMBER: 19-453 N' COHESIVE SOIL CONSISTENCY DATE STARTED: 05-29-2020 DATE COMPLETED: 05-29-2020 HOLE N: VS @ TP -1 CREW: Sam Rabe ETT SURFACE ELEVATION: PROJECT: AEowhead Meadows WATER ON COMPLETION: ADDRESS: HAMMER WEIGHT: 35 lbs. LOCATION: Springfield, Oregon CONE AREA: 10 sq. cm DEPTH BLOWS PER10cm RESISTANCE K kms GRAPH OF CONE RESISTANCE 0 50 100 150 N' COHESIVE SOIL CONSISTENCY TORQUE fl. -lbs. SHEAR psf 0 0 1 ft 0 - 5 17.6 5 MEDIUM STIFF - 6 21.2 ••• 6 MEDIUM STIFF - 2 ft 6 21.2 ••• 6 MEDIUM STIFF 25 2750 - 5 17.6 5 MEDIUM STIFF - 8 28.2 ••••• 8 MEDIUM STIFF - 3 ft 8 28.2 ••••• 8 MEDIUM STIFF - 1 m 12 42.3 •^^^^^• 12 STIFF 40 4400 - 21 64.4 ............•••••• 18 VERY STIFF 75 8250 4 ft 5 ft 6 ft -2m 7 ft 8 ft 9 ft 3m 10ft I I ft 12 fl -4m 13 f1 0a@W6WW XW7YLS (Branch BLOWS PER10cm RESISTANCE K kms ENGINEERING- DYNAMIC VANE LOG COHESIVE SOIL CONSISTENCY TORQUE fl. -lbs. PROJECT NUMBER: 19-453 5 DATE STARTED: 05-29-2020 5 DATE COMPLETED: 05-29-2020 HOLE N: VS @ TP -3 - 5 CREW: Sam Rabe Err SURFACE ELEVATION: 5 PROJECT: Arrowhead Meadows WATER ON COMPLETION: ADDRESS: HAMMER WEIGHT: 35 lbs. LOCATION: Springfield, Oregon CONE AREA: 10 sq. cm DEPTH BLOWS PER10cm RESISTANCE K kms GRAPH OF CONE RESISTANCE 0 50 100 150 N' COHESIVE SOIL CONSISTENCY TORQUE fl. -lbs. SHEAR psf - 1 ft 5 17.6 5 MEDIUM STIFF - 5 17.6 5 MEDIUM STIFF - 5 17.6 5 MEDIUM STIFF - 2 ft 8 28.2 ••••• 8 MEDIUM STIFF 25 2750 - 9 31.7 •^^^^ 9 STIFF - 10 35.3 •^^^^• 10 STIFF - 3 ft 10 35.3 •^^^^• 10 STIFF m 4 ft 5 ft 6 ft -2m 7 ft 8 ft 9 ft 3m 10ft I I ft 12 fl -4m 13 f1 0a@W6WW XW7YLS b STATE OF OREGON (, /Lo ,)C—: „ -WATER WELL REPORT �. (as required by ORS 539.76.5) JF:N 141933 (8) WELL TESTS: Minimum testing time is I hour Flowing ❑ Pump -� Bailer ❑ AG ❑ Artesian Yield gallmin Drawdown Drill stem at Time d) `Zso I la. _ IEmpemmre of Water .'S7D Depth Artesian Plow Found Was a water analysis done? ❑ Yes By who Did airy saran comain wnb, not suitable roe intended ase? ❑ To. DID, ❑ salty ❑ Muddy ❑ odor ❑ c mpod' ❑ Other Depth of strats: F Wt&AMON OF WELL by legal description: County2�NE r Htude - i.nngitude Tdwnship_JV7_5' N ors. Range 9 Lai Fpr W, IYM. — sartion 3* A 14 'rax ua_aL tlO r t _ Dlpcubdi io Street Atldres, of WmR. ell (o earest addmas SPGR 9747A (10) ST�A�IC WATER LEVEL: - IL below iand.sret ce. Data Artesian pressure Ib, per squire, inch. Date (H) WATER BEARING ZONES Depth at which water was Prom 'Ib Estimated Plow Rate SWL l (12) WELL LOG: Icorrify that the work I performed on the construction, alteration, m abeudnn- .art of this well is in compliance with Oregon well construction standards. Materials mod and information reported above are true to my best knowledge and relief..- W WC Number 567g— Signed - _. _. - - .Date /2`2 -].� (bonded) Water Well Carchaptor CertiHceHom I accept responsibility for the comwedon, ala during thi is true to RESOURCES DEPARTMENT SECOND COPY -CONSTRUCTOR THIRD COPY -CUSTOMER (1) O8yNER: Well Number Name �,Q(Jl0 /17 /t_GER Address _ r ciry s FD Sure FS zlp 75� (2) TYPE OF WORK: New Welt Deepen Recondition ❑Abandon (3) DRILL METHOD: dd,, 11Rotary Air ElRotary Mud X Cable - ❑ Other (4) PROPOSED USE: FFAA Iw Domestic ❑ Commwity ❑ Industrial -❑ Irrigation ❑ Thermal ❑ D ncghp s Ll Ode, (5) BORE HOLE CONSTRUCTION: - Special Conswdma cappraisal El Yes El No Depth of Completed Well /J�' �J �'t. Exp1mbda used ❑ Firs ❑ No Type _ _- Amoun HOLE SEAL soounI Diameter Ina. Ib Material boom To _ sac or to m li 0 How was seal placed: Method ❑ A ❑ B MC ❑ D ❑ E ❑ Other Backfill placed Erna_ ft. to R... Material G.1 placed from— R. m - ft. Size rff emvo (6) CASING/LINER: DiazFrom Ib Ganga steel Handle wnaea Tbraaam Can" .iD N [I ❑ x El F-1 ❑ Fl - El El F1 El ,j;jd ❑ ❑ . ❑ ❑ .Liner,. ❑. ❑ ❑ ❑ ❑ ❑ ❑ ❑ Final location of ahoe(s) (7) PERFORATIONS/SCREENS: ❑ Permormna Method ❑ Scream Type Material - Slot "b"'pe From Ib sia, Number Diameter sire Lasing Liner ❑ ❑. _ El 7- ❑ ❑ ❑ .. ❑ ❑ ❑ (8) WELL TESTS: Minimum testing time is I hour Flowing ❑ Pump -� Bailer ❑ AG ❑ Artesian Yield gallmin Drawdown Drill stem at Time d) `Zso I la. _ IEmpemmre of Water .'S7D Depth Artesian Plow Found Was a water analysis done? ❑ Yes By who Did airy saran comain wnb, not suitable roe intended ase? ❑ To. DID, ❑ salty ❑ Muddy ❑ odor ❑ c mpod' ❑ Other Depth of strats: F Wt&AMON OF WELL by legal description: County2�NE r Htude - i.nngitude Tdwnship_JV7_5' N ors. Range 9 Lai Fpr W, IYM. — sartion 3* A 14 'rax ua_aL tlO r t _ Dlpcubdi io Street Atldres, of WmR. ell (o earest addmas SPGR 9747A (10) ST�A�IC WATER LEVEL: - IL below iand.sret ce. Data Artesian pressure Ib, per squire, inch. Date (H) WATER BEARING ZONES Depth at which water was Prom 'Ib Estimated Plow Rate SWL l (12) WELL LOG: Icorrify that the work I performed on the construction, alteration, m abeudnn- .art of this well is in compliance with Oregon well construction standards. Materials mod and information reported above are true to my best knowledge and relief..- W WC Number 567g— Signed - _. _. - - .Date /2`2 -].� (bonded) Water Well Carchaptor CertiHceHom I accept responsibility for the comwedon, ala during thi is true to RESOURCES DEPARTMENT SECOND COPY -CONSTRUCTOR THIRD COPY -CUSTOMER WATER WELL REPORT STATE OF OREGON (1) OWNER (2) TYPE OF WORK (check): New Wall M Deepening ❑ Remnditfpning ❑ abandon ❑ If abandomnent, d Ina material and oracadum in Item 12. (3) TYPE OF WELL: (4) PROPOSED USE (check): amaryar M Delves o Dene, m roaonEv o ananden 0 uJaMud 0 ➢¢ o L i ntfm. 0 1 weu ❑ ONer o 0 B o 1nn<.met w;dM1drawel o Pa;almt+m. 0 (5) CASING INSTALLED: steel m mane ❑ Tfavnded ❑ Wetdea M ..._6..."Dian.from...+..g...__fate....�...... ft. c.,a .., Zr2Q.._............. "Diem. tmm............._ f400 ... ....... ', Cmree .......:...._......_........ LINER INSTALLED: ...........L"Diam.reen:........_.:. R.w............... a. Dag. ......._............._._... (0) PERFORATIONS: Perforated? my. ',_ No Type of porforaWr oned Air snag mfmationa 1/4 iaby 1 ..._ ........_._..._,env.O........:......._ pmtarationa ftom...._22.. ft.b....,At..__ ft. ...._...._..._._................_.._......... Perforations Dom............... ft,. .........__:. & ......... parforatimu Dom .....:......... fL W........... _.. ft (7) SCREENS: wdi amaen installad? ❑ Yes m No Maoofadurale Name ..........._._. ........ —._........ - ...... ......._..... Type ... ..... ..__...... ._...m.... Mcdel No ...................... Diem. ........................ Slat Rea ............ Setf . . .......... ftb...... ......... R Diem . ............ filo[Sim............ Set from._.._....._. ft. to............... It. (9) WELL TESTS: Drawdown is amnent ware level Is lowerad below.tabe Ievel Annat 25: ¢el./mfn. withdnll stem at 6,9ft I Ina Railertest .al.hnm with f.&.adnwnaftar lea �anian flow ypm. ,ndureofwater Deptherteeiao Flawenmwtared,........_.{t. (9) CONSTRUCTION: 9p ial nranaarm: Yon❑ Nom Wauaeai-Matodaluaad..... end...pQe.>neFAt..._------....._---- ._..:___. Wellsealedfmmlandeerface to....................�'a....... _.—.--------------- ._.�..._. fL Diameter a wall bare to b Ueou m' aenl....1.Q ........... w. Numberafeeckeo{cement uazdinwelleanl .............. 1.7 ................. _------ anela Howwa.cementaraatpin d? .areawore...gmuted ........ ......... ...... ` Wv Pump intoned? ................... ...... T$pe.......... _ fn'........_:. Depth .... _...... ft. Wasadriveehaeuanl MY. ON. muga............ aim: Iocation............ ft. Did any strata eantaia unusable water! ❑ Yes Z No Type of Watea _ depth of errata Method of sealing atrabe off W n I ked" ❑Y UN - S' f T _ W II No. DEG241%�I e WATER RE3(Y(JRLS'F)jo+-" SAL..,',. OREGON (10) LOCATION OF WELL: comely Lane - -. nduer. wen number A u seeefon 34 T 178 R 2W W M 1500 fa-- sik saiwvidnn Address at well location: - -_ (11) WATER LEVEL: Completed well. Depthatwhirbwaterwaafkntfouad 13 ft Stain, level 8 ft below land eurf.. Date 11-23-81.-.. �m,maeaara lbs.,on,uareinel,liode . (12) WELL LOG: Diametentweubeiow®air,g...........__6s_._. - Damhdrined 55- _ rt. Dewrnfeou,netedweu 45 ...f_ Fen,ation: Deeeeine color, teedrae, grain dra and afro tura of material.; med.how nennueee and mune of oneb anatum and aquifer Woetrao J, with at least one entry for en& eleepya of formstien. Repent each dunga in waition of Statin Water Level and indicnto pAndped watar-brelog anent. DAUWW Machin Operator'. Cerlfffeatlon Thia well wasmr,etnmfad under my direct supervision. Materiels used and iuffermatian rep a true to �y best knowledge and belief. (signed] .......�'piN/r DrillinSMaciune0,autoYa Lice.,ee Na ........... ......................... Water Well Contractor'. Certifleatlon This well was drilled under r jurisdiction and this report is true in tins test of ny knowledge and belief. Nan,.. Cae,@Y. _J.4Slee...W2.7.)<..ASttila-,,Tt&_CR......lao................ wma<n Grmm®Pmadom Dys. oraumeS Addran.-3.7. ...ltan7,gmut.. d ,..k .eaaant..?3i1J.,...OR. [signed] ..:YX . .. .. ..................... ....idi i Cantraene'.l.i«n.a No ....559...E ..............._.11-23-..._-19 Al NOTICE TO WATER WELL CONTRACTOR - WATER RESOURCES DEPARTMENT, SP're$ee4aU nem oole f <opy or u,Y ,e,at arca onIX`AN WSM ere to h mM elf fe, Weoo en e— fmm eM dw<( w<u X41 ... _. Map Unit Description: Coburg -Urban land cernplex--Lane Cmnty Area, Oregon Wieilenmann Property Lane County Area, Oregon 32—Coburg-Urban land complex Map Unit Setting National map unit symbol. 2369 Elevation. 100 to 1,300 feet Mean annual precipitation: 30 to 60 inches Mean annual air temperature: 50 to 55 degrees F Frost -free period. 160 to 235 days Farmland classification. Farm land of statewide importance Map Unit Composition Coburg and similar soils: 55 percent Urban land. 30 percent Minorcomponents: 4 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Coburg Setting Landform: Stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across -slope shape: Linear Parent material. Loamy alluvium over clayey alluvium Typical profile H1 - 0 to 18 inches. silty clay loam H2 - 18 to 53 inches: silty clay H3-53 to 65 inches: fine sandy loam Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Moderately well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 in/hr) Depth to watertable: About 18 to 30 inches Fraquencyofflooding: None Frequencyofponding. None Available water storage in profile: High (about 11.0 inches) Interpretive groups Lard capability classification (irrigated): 2w Lard capability classification (nonirrigated): 2w Hydrologic Soil Group: C Forage suitability group: Moderately Well Drained < 15% Slopes (G002XY0040R) Hydric soil rating. No LSM Natural Resources Wieb Soil Survey &1212020 irk Conservation Serves National Cooperative Soil Survey Pege1 oft Map Unit Description: Coburg -Urban land cernplex--Lane County Area, Oregon Wietlonmann Property Description of Urban Land Interpretive groups Land capability classification (irrigated): None specified Lard capability classification (nonirrigated): 8 Hydric sal rating. No Minor Components Conser Percent of map unit: 4 percent Landform: Stream terraces Hydric sal rating. Yes Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 16, Sep 10, 2019 LSM Natural Resources Web Soil Survey 6/12/21)20 211 Conservation Service National Cooperative Soil Survey Page 2 of 2 Map Unit Description: Courtney gravelly silty day loam, 0 to 3 percent slopes --Lane County Wiedenmann Property Area, Oregon Lane County Area, Oregon 2224A—Courtney gravelly silty clay loam, 0 to 3 percent slopes Map Unit Setting National map unit symbol. 2xpsh Elevation. 160 to 800 feet Mean annual precipitation: 39 to 59 inches Mean annual air temperature: 50 to 54 degrees F Frost -free period. 165 to 210 days Farmland classification. Farm land of statewide importance Map Unit Composition Courtney and similar soils. 85 percent Minorcomponents: 12 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Courtney Setting Landform: Drainageways on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear, concave Across -slope shape: Concave Parent material. Alluvium Typical profile Al - O to 8 inches: gravelly silty clay loam A2 - 8 to 17 inches: gravelly silty clay loam 2Btgl -17to 24 inches: gravelly clay 2Btg2 - 24 to 33 inches: gravelly clay 3Cg- 33 to 48 inches. very gravelly clay loam 4C - 48 to 60 inches: extremely gravelly sand Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: 10 to 19 inches to abrupt textural change Natural drainage class: Poorly drained Capacity of the most limiting layer to transmit water(Ksat): Very low to moderately low (0.00 to 0.01 in/hr) Depth to water table: About Oinches Frequencyofflooding: None Frequencyofponding. Frequent Available water storage in profile: Very low (about 2.5 inches) Interpretive groups Land capability classification (irrigated): 4w Land capability classification (nonirrigated): 4w Hydrologic Soil Group: D LSDA Natural Resources Web Soil Survey &1212020 i Conservation Serves National Cooperative Soil Survey Page 1 of 2 Map Unit Description: Courtney gravelly silty day loam, 0 to 3 percent slopes --Lane County W edenmann Property Area, Oregon Forage suitability group: Poorly Drained (G002XYOO6OR) Hydnc soil rating. Yes Minor Components Awbrig Percent of map unit: 6 percent Landform: Drainageways on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across -slope shape: Concave Hydric soil rating. Yes Bashaw Percent of map unit: 4 percent Landform: Depressions on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Concave Across -slope shape: Concave Hydric soil rating. Yes Conser Percent of map unit: 2 percent Landform: Depressions on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Concave Across -slope shape: Concave Hydric soil rating. Yes Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 16, Sep 10, 2019 LSDA Natural Resources Mb Soil Survey 6/122020 i Conservation Serves National Cooperative Soil Survey Page 2 of 2 Map Unit Description: Nekia silty clay loam, 30 to 50 percent slopes—Lane County Area.. Wedenmann Property Oregon Lane County Area, Oregon 89F—Nekia silty clay loam, 30 to 50 percent slopes Map Unit Setting National map unit symbol. 239k Elevation. 350 to 1,400 feet Mean annual precipitation: 40 to 60 inches Mean annual airtempemture: 52 to 54 degrees F Frost -free period. 165 to 210 days Farmland classification. Not prime farmland Map Unit Composition Nekia and similar soils: 85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Nekia Setting Landform: Hills Landform position (two-dimensional/: Backslope, shoulder Landform position (three-dimensional): Side slope, nose slope Down-slope shape: Linear Across -slope shape: Linear Parent material. Colluvium and residuum derived from basalt and tuff Typical profile Oi-Oto 1 inches. slightly decomposed plant material H1 - 1 to 11 inches: silty clay loam H2 - 11 to 36 inches. clay H3 - 36 to 40 inches: unweathered bedrock Properties and qualities Slope: 30 to 50 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Natural drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksatl: Moderately high (0.20 to 0.57 in/hr) Depth to water table: More than 80 inches Frequencyofflooding: None Frequencyofponding. None Available water storage in profile: Low (about 5.7 inches) Interpretive groups Lard capability classification (irrigated): None specified Lard capability classification (nonirrigated): 6e Hydrologic Soil Group: C LSDA Natural Resources Web Soil Survey &1212020 i conservation Serves National Cooperative Soil Survey Page 1 ort Map Unit Description: Nekia silty clay loam, 30 to 50 percent slopes --lane County Nee, Wiedenmann Property Oregon Hydfic soil rating: No Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 16, Sep 10, 2019 LSDA Natural Resources Web Soil Survey 6/122020 i Conservation Serme National Cooperative Soil Survey Page 2 of 2 M 2'45'N M 2'11 N Sol Map—Lane County Area, Oregon Wed enanann Property ) 3 3 m N Rale: Apwb-[(a Sr. 11')fi q p N Nis Ao m tm � an M�C�P tea: W�hHr3a C ar_Nrala: NGS99 FAge ES:IIIM]me1CN W1,539 p51)A Natural Resources Web Soil Survey &1212020 �i Conservation Serme National Cooperative Soil Survey Page 1 a 3 M° 2 D"N Sal Map—Lane County Area, Oregon (VJedenmann Property) _SD, Natural Resources web Sol Survey 6/1 212 9 2 9 all Conservation Service National Cooperative Shc Survey Page 2 of 3 MAP LEGEND MAP INFORMATION Area at Were. tA09 Spat Area The sal surveys that comprise your AOl were mapped at Area of Interest(AOI) 1:20,090. Q Stany Spat Soils Very Sony Spa Waming: Shc Map may not be vapid al Mrs scale. 0 Soil Map Unit Polygons 9 VJrf Spot p Enlargement of maps beyond the scale of mapping can cause ,.,. Soil Map Unic Lines misunderslantling of the tletail of mapping and accuracy of soil 4 Other line placement. The maps do not show the small areas of Soil Map Unit Points soils that could have been shown at a more detailed Special Line Feelcontrasting Special Point Features scale. Lg Blowout water Features Streams and Canals Please rely on the bar scale on each map sheet for map ® Boraw Pit measurements. Trenspartatian Clay Spot Rails Source of Map: Natural Resources Conservation Service 0 Closed Depression Web Soil SurveyLIRL: Interstate Highways Coordinate System: web Mercator(EPSG:355]) Gravel Pit US Routes Maps from the Web Soil Survey are based on the Web Mercator Gravely Spa Malor Roads projection, which preserves and shape but ion that schdistorts and area, projection that preserves area, such as the ® Landfill Local Roads Abersdistance o Albers equal-area conic projection, should be used if more Lara Flaw accurate calculations of distance or area are req uired, Background aga Marsh or swamp . Aerial Photography This productis generated from the USDA­gRCS certified data as of Ne version dates) listed below * Mine or Query Suer Survey Area: Lane County ® Miscellaneous Ydscer 10, 2019 Survey Area Data: Version 16, Sep 10, 2019 Sep ® Perennial VMmer Shc map units are labeled (as space allows) for map scales y, Rock Outcrop 1:50,099 or larger. A Saline Spot Dates) aerial images were photographed: Jun 12, 20191 19, 2019 Sandy Spot The odhophoto or other base map on which the soil lines were Severely Eroded Spot compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor Sinkhole shifting ofmap and boundaries may be evident. �p Slide or Slip Sodic Spot _SD, Natural Resources web Sol Survey 6/1 212 9 2 9 all Conservation Service National Cooperative Shc Survey Page 2 of 3 Sal Map�ane Cmdy Area, Oregon Map Unit Legend Wielenmann Property LSUa Natural Resources Web Soil Survey 6/122020 i Conservation Serme National Cooperative Soil Survey Page 3 of 3 Map Unit Symbd Map Unit Name Acres in AOI Percent of AOI 32 Coburg4 rEan land cornpie 2.3 28.T% WF Nelda silly day loam, W to SO Percent slopes 2.6 32.3% 108A Pang. sit loam, i to 4 percent slopes 0.2 2.2% 2224A Cmdney gravelly silly day can, 010 3 percent slopes 3.0 36.8% Taste for Area of Interest 8.1 100.0% LSUa Natural Resources Web Soil Survey 6/122020 i Conservation Serme National Cooperative Soil Survey Page 3 of 3 APPENDIX B: Recommended Earthwork Specifications GEOTECHNICAL SPECIFICATIONS General Earthwork t. All areas where structural fills, fill slopes, structures, or roadways are to be constructed shall be stripped of organic topsoil and cleared of surface and subsurface deleterious material, including but limited to vegetation, roots, or other organic material, undocumented fill, construction debris, soft or unsuitable soils as directed by the Geotechnical Engineer of Record. These materials shall be removed from the site or stockpiled in a designated location for reuse in landscape areas if suitable for that purpose. Existing utilities and structures that are not to be used as part of the project design or by neighboring facilities, shall be removed or properly abandoned, and the associated debris removed from the site. z. Upon completion of site stripping and clearing, the exposed soil and/or rock shall be observed by the Geotechnical Engineer of Record or a designated representative to assess the subgrade condition for the intended overlying use. Pits, depressions, or holes created by the removal of root wads, utilities, structures, or deleterious material shall be properly cleared of loose material, benched and backfilled with fill material approved by the Geotechnical Engineer of Record compacted to the project specifications. 3. In structural fill areas, the subgrade soil shall be scarified to a depth of 4 -inches, if soil fill is used, moisture conditioned to within z% of the materials optimum moisture for compaction, and blended with the first lift of fill material. The fill placement and compaction equipment shall be appropriate for fill material type, required degree of blending, and uncompacted lift thickness. Assuming proper equipment selection, the total uncompacted thickness of the scarified subgrade and first fill lift shall not exceed 8 -inches, subsequent lifts of uncompacted fill shall not exceed fl- inches unless otherwise approved by the Geotechnical Engineer of Record. The uncompacted lift thickness shall be assessed based on the type of compaction equipment used and the results of initial compaction testing. Fine-grain soil fill is generally most effectively compacted using a kneading style compactor, such as a sheeps-foot roller; granular materials are more effectively compacted using a smooth, vibratory roller or impact style compactor. 4. All structural soil fill shall be well blended, moisture conditioned to within z% of the material's optimum moisture content for compaction and compacted to at least 9o% of the material's maximum dry density as determined by ASTM Method D-1557, or an equivalent method. Soil fill shall not contain more than to% rock material and no solid material over 3 -inches in diameter unless approved by the Geotechnical Engineer of Record. Rocks shall be evenly distributed throughout each liftof fill that they are contained within and shall not be clumped together in such away that voids ren occur. 5. All structural granular fill shall be well blended, moisture conditioned at or up to 3% above of the material's optimum moisture content for compaction and compacted to at least go% of the material's maximum dry density as determined by ASTM Method D-1557, or an equivalent method. 95% relative compaction may be required for pavement base rock or in upper lifts of the granular structural fill where a sufficient thickness of the fill section allows for higher compaction percentages to be achieved. The granular fill shall not contain solid particles over z -inches in diameter unless special density testing methods or proof -rolling is approved by the Geotechnical Engineer of Record. Granular fill is generally considered to be a crushed aggregate with a fracture surface of at least 7o% and a maximum size not exceeding t.5 -inches in diameter, well -graded with less than to%, by weight, passing the No. zoo Sieve. 6. Structural fill shall be field tested for compliance with project specifications for every 2 -feet in vertical rise or Soo cy placed, whichever is less. In-place field density testing shall be performed by a competent individual, trained in the testing and placement of soil and aggregate fill placement, using either ASTM Method D -t556/4959/4944 (Sand Cone), D-6938 (Nuclear Densometer), or D-2937/4959/4944 (Drive Cylinder). Should the fill materials not be suitable for testing by the above methods, then observation of placement, compaction and proof-rollingwith a loaded to cy dump -truck, or equivalent ground pressure equipment, by a trained individual may be used to assess and document the compliance with structural fill specifications. Utility Excavations I. Utility ezeavations are to be ezeavated to the design depth for bedding and placement and shall not be over-ezeavated. Trench widths shall only be of sufficient width to allow placement and proper construction of the utility and backfill of the trench. z. Backfilling of a utility trench will be dependent on its location, use, depth, and utility line material type. Trenches that are required to meet structural fill specifications, such as those under or near buildings, or within pavement areas, shall have granular material strategically compacted to at least the spring -line of the utility conduit to mitigate pipeline movement and deformation. The initial lift thickness of backfill overlying the pipeline will be dependent on the pipeline material, type of backfill, and the compaction equipment, so as not to cause deflection or deformation of the pipeline. Trench backfill shall conform to the General Earthwork specifications for placement, compaction, and testing of structural fill. Geotextiles I. All geotextiles shall be resistant to ultraviolet degradation, and to biological and chemical environments normally found in soils. Geotextiles shall be stored so that they are not in direct sunlight or exposed to chemical products. The use of a geotextile shall be specified and shall meet the following specification for each use. Suberade/Aggregate Separation Woven or nonwoven fabric conforming to the following physical properties: • Minimum grab tensile strength ASTM Method D-4632 ISO lb • Minimum puncture strength (CBR) ASTM Method D-6241 37116 • Elongation ASTM Method D-4632 15% • Maxi mum apparent opening size ASTM Method D-4751 No. 40 • Minimum permittivity ASTM Method D-4491 0.05 s� Drainage Filtration Woven fabricconforming to the following physical properties: • Minimum grab tensile strength ASTM Method D-4632 11016 • Minimum puncture strength (CBR) ASTM Method D-6241 220 Ib • Elongation ASTM Method D-4632 50% • Maxi mum apparent opening size ASTM Method D-4751 No. 40 • Minimum permittivity ASTM Method D-4491 0.5 s1 Geoerid Base Reinforcement Extruded biaxially ortriaxially oriented polypropylene conformingto the following physical properties: • Peak tensile strength ASTM Method D-6637 925 lb/ft • Tensile strength at 2% strain ASTM Method D-6637 300 lb/ft • Tensile strength at 5% strain ASTM Method D-6637 600 lb/ft • Flexural Rigidity ASTM Method D-13SS 250,000 mg -cm • Effective Opening Size ASTM Method D-4751 1.5x rock size Stormwater Management Plan Prepared by: Christopher Morris, E.I.T. chrism@branchenoineerino.com Tentative Site Plan Review Arrowhead Meadows Springfield, OR For Nathan W iedenmann and Mike Blair EXPIRES:12131121 Prepared using: Springfield's Engineering Design Standards and Procedures Manual Eugene's 2014 Stormwater Management Manual July 7, 2020 E'N0GINEERING= Since 1977 civil • transportation structural • geotechnical SURVEYING www.BranchEngineering.com Contents Page No. 1.0 Introduction.............................................................................................................................. l 2.0 Existing Conditions ............... 2.1 Topography 2.2 Soils 2.3 Existing Stormwater System 2.4 Infiltration Rates 3.0 Proposed Development ........................ 3.1 Pollutants of Concern 3.2 Name and Status ofBeceiving Waters 4.0 Stormwater Constraints..........................................................................................................2 5.0 Proposed Development Stormwater Description 6.0 Hydrologic and Hydraulic Analysis.......................................................................................2 6.1 Computer Model 6.2 Computer Model Data 7.0 Maintenance.............................................................................................................................3 8.0 Conclusion Appendices Appendix A Appendix B Description Soils Map and Description HydroCAD Report Arrowhead Meadows Stormwater Report (19-453) 1.0 Introduction The subject properties are one parcel of land approximately 1.00 acre in size located in Springfield, Oregon The subject property is listed as Tax Map 17-02-34-34, Tax Lot 700. A three building multi- family development, public street extension, drive and parking lot areas, concrete walkways, landscape and stormwater treatment areas and associated utilities are the proposed developments at the site. This study and report was prepared to address the City of Springfield's stormwater requirements for the development. 2.0 Existing Conditions The parcel is a single lot that fronts Main Street/Highway 126 to the north, Mountaingate Subdivision to the south, with residential lots to the east and west. The Aster Street extension will split the lot into north and south portions. 2.1 Topography The existing site is relatively flat and generally drains north to south over the northern portion of the parcel and very steep across most of the southern portion of the parcel which drains sharply to the north 2.2 Soils According to the Web Soil Survey of Lane County. Oreeon, by the Natural Resource Conservation Service, the soils on the site are Coburg -Urban land complex (Soil Number 32), Courtney silty clay loam (Soil Number 2224A) and Nekia silty clay loam, 30-5096 slopes (Soil Number 89F) from north to south respectively. Coburg -Urban land complex and Courtney silty clay loam are both described as hydric soils of Hydrologic Group D and Nekia silty clay loam is of Hydrologic Group C. The soil map and descriptions documents are attached as Appendix A- 2.3 2.3 Existing Stormwater System The project site is relatively unimproved without an established drainage system. There is a stormwater easement and a 36" public stormwater pipe that splits the northern portion of the parcel and drains east to west 2.4 Infiltration Rates Infiltration facilities are not being proposed for the site's stormwater disposal as in-situ soils are poorly draining. 3.0 Proposed Development The proposed development is to construct two multi -unit apartment buildings on the northern portion of the parcel and a single multi -unit townhouse building against the sidehill on the southern portion of the parcel. There will be an extension of the Aster Street public right-of-way. There will also be a 20 -foot -wide private drive aisle, associated parking, concrete walkways, associated public and private utilities and landscaping. The total impervious area for the entire site is approximately 0.53 acres (23,200 sq ft). 3.1 Pollutants of Concern The reasonably expected pollutants of concern from this type of development are: • Nutrients • Pesticides, Herbicides, Fungicides • Metals (Zinc, Copper, Lead etc.) • Oil, grease and other petroleum Arrowhead Meadows Stormwater Report (19-45 3) • Sediment • litter • Oxygen demanding materials • increased thermal loading 3.2 Name and Status of Receiving Waters The stormwater from this site drains to the public stormwater system that outfalls into the 48- Street Channel that drains north to the McKenzie River. The McKenzie River is a 303(d) listed waterway for a variety of pollutants. According to the City of Springfield's Wellhead Protection Areas Map, the project site is located outside the 100 -year Zone of Concentration (100 -year Time of Travel) wellhead protection area designated by the City and the Springfield Utility Board. 4.0 Stormwater Constraints The current planned development includes impacts to existing wetlands; therefore, the stormwater design will need to conform to requirements set by the City, Oregon Department of Environmental Quality (DEQ) and National Marine Fisheries Service (NMFS) for water quality and flow control. NMFS' requirements include stormwater retention or detention facilities to limit discharge to match pre - developed discharge rates for 50% of the 2 -year storm event and the 10 -year storm event. The City of Springfield requires that the post development 25 -year storm event runoff not exceed the pre - developed 25 -year runoff. Per the Department of Environmental Quality, the treatment constrain of the project site are that all discharged stormwater must be treated through Best Management Practices. Therefore, the storm facilities will treat the water quality storm event (50%NOAA 2 -year storm event). Detention/retention requirements will be met by sizing the orificed standpipes within the flow control detention vaults so that discharges do not exceed 50% of the 2 -year storm event and checking that the pre -developed discharge rates for the 10 -year storm event are not exceeded. 5.0 Proposed Development Stormwater Description The City of Springfield defers to Eugene's Stormwater Management Manual (2014) for stormwater treatment facility design when designinformation is not included in the City of Springfield Engineering and Design Standards and Procedures Manual. The proposed development will treat stormwater runoff through stormwater treatment males before discharging to StormCapture detention tanks that are orifice controlled to allow for detention to NMFS requirements (50% of NOAA 2 -yr event). 6.0 Hydrologic and Hydraulic Analysis 6.1 Computer Model In preparing this Stormwater Management Plan for the project site, Branch Engineering utilized the HydroCAD 10.0 software. This is a computer program used to model, analyze and design hydrosystems of drainage basins. HydroCAD computes Santa Barbara Urban Hydrographs (SBUH) using rainfall data supplied by the designer. The SBUH method is a recognized analysis method by the City of Springfield and is appropriate for a project site of this size. Once the appropriate data is input to HydroCAD, the Arrowhead Meadows Stormwater Report (19-45 3) drainage basin has a hydrograph and runoff flow for the desired storm event. The HydroCAD model is attached as Appendix B. 6.2 Computer Model Data HydroCAD needs data supplied from the designer that describes the drainage basin in order to create the hydrograph. Below is the data that is needed to describe each drainage basin. o Storm Event For the purposes of this design, the City of Springfield's design storm events are as follows: Water Quality Event (50%NOAA 2 -yr event) 0.83 inches / 24 hours 2 -year Storm Event (NOAA) 3.30 inches / 24 hours 10 -year Storm Event 4.30 inches / 24 hours 25 -year Storm Event 4.80 inches / 24 hours o Impervious Area Pavement, sidewalks, hardscapes and rooftops are all impervious surfaces. o Pervious Area Lawns and open space are pervious areas. The pervious area is all that area that is not impervious. o Runoff Curve Numbers The Runoff Curve Number is based on the type of surface and the Hydrologic Group of the soils. As stated earlier in the report, the soils on the site are in Soil Hydrologic Group C and D. Per Table 2-2a of the Urban Hydrology l'or Small Watersheds (TR -55) table, the Curve Number is 87 for areas that were not historic wetland, 90 for historic wetland areas and 98 for impervious areas. o Time of Concentration The minimum time of concentration of five minutes was used for modeling. 7.0 Maintenance The treatment and infiltration facilities are located on private property and will be owned and maintained by the property owners. Maintenance will be per the City of Springfield's Engineering Design Standards and Procedures Manual. Repairs to the facilities shall be made in accordance with the City of Springfield's Engineering Design Standards and Procedures Manual. 8.0 Conclusion The proposed stormwater system for the new office building and parking areas additions have been designed in accordance with the City of Springfield's Engineering Design Standards and Procedures Manual. /.\»:1►IQKV91 Soils Map and Description m2.N Sol Map—Lane County Area, Oregon a a m NapSok1:3,(loo lfpntisian A pdait(S.Sx 11') 9rH. A p N�s a a m rap zap a Aa rao mo aoo ®p N�POJamn: wmrormwanatas:�sa Edge Isis: ulm Are 1M �sa D5W Natural Resources Web Soil Survey IMM20 3i Conservation Serme National Cooperative Soil Survey Page 1 a 3 m•IaN a•1.N Soil Map—Lane County Area, Oregon _SD, Natural Resources web Sol Survey 11W2D2D alaill Conservation Service National Cooperative Sail Survey Page 2 of 3 MAP LEGEND MAP INFORMATION Area at Wake. tA09 Spoil Area The sal surveys that comprise your AOI were mapped at Areaalnteresr(AQII Q army Spa 1:20,090. Soils Very Sony SpaWaming: Soil Map may not be valud al Mrs scale. 0 Soil Map Unit Polygons 9 VJrf S p a Enlargement of maps bethe scale of mapping can cause ,.,. Soil Map Unic Lines md Sell of the etail of mapping and accuracy of soil 4 Other line placement. The maps do not show the small areas of Map Unit Points contrasting soils that could have been shown at a more detailed Special Line FeaturesSoil Special Point Features scale. Lg Blowout water Features Streams and Canals Please rely on the bar scale on each map sheet for map ® Borrow Pit measurements. Trenspartatian Clay Spot Rails Source of Map: Natural Resources Conservation Service 0 Closed Depresdan Web Soil SurveyURL: Interstate Highways Coordinate System: web Mercator(EPSG:3m5]) Gravel Pit US Routes Maps from the Web Soil Survey are based on the Web Mercator Gravely Spa Major Roads projection, which preserves and shape but ion that schdistorts and area, projection that preserves area, such as the ® Landfill Local Roads Abersdistance o Albers equal-area conic projection, should be used if more Lava Flow accurate calculations of distance or area are req uired, Background aga Marsh or swamp . Aerial Photography This productis generated from the USDA­gRCS tended data as of Ne version date(s) listed below .�. Mine or Query Soil Survey Area: Lane County Area, ® Miscellaneous Ydscer ep10,Oregon 2019 Survey Area Data: Version 16, Sep 10, 2019 ® Perennial VMmer Sail map units are labeled (as space allows) for map scales y, Rock Outcrop 1:50,099 or larger. A Saline Spot Dates) aerial images were photographed: Jun 12, 2019i 19, 2019 Sandy Spot The orihophoto or other base map on which the soil lines were Severely Eroded Spot compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor Sinkhole shifting ofmap unit boundaries may be evident, �p Slide or Slip Sodic Spot _SD, Natural Resources web Sol Survey 11W2D2D alaill Conservation Service National Cooperative Sail Survey Page 2 of 3 Sal Map�ane Cmdy Area, Oregon Map Unit Legend LSIA Natural Resources Web Soil Survey 1/82020 iMi Conservation Serme National Cooperative Soil Survey Page 3 of3 Map Unit Symbd Map Unit Name Acres in AOI Pescara of AOI 32 Coburg4 ffian land cornplex D.2 18.1% 89D Nekia silly day loam, 12 to 20 percent slopes 0.0 3.4% 8gF Nelda silly day loam, 3010 50 percent slopes 0.5 41.T% 2224A Cmdney gravelly silly day can, 010 3 percent gapes 0.4 38.8% Totals fcr Area of Interest 1.1 100.0% LSIA Natural Resources Web Soil Survey 1/82020 iMi Conservation Serme National Cooperative Soil Survey Page 3 of3 Map Unit Description: Coburg -Urban land canplex--Lane Cmnty Area, Oregon Lane County Area, Oregon 32—Coburg-Urban land complex Map Unit Setting National map unit symbol. 2369 Elevation. 100 to 1,300 feet Mean annual precipitation: 30 to 60 inches Mean annual air temperature: 50 to 55 degrees F Frost -free period. 160 to 235 days Farmland classification. Farm land of statewide importance Map Unit Composition Coburg and similar soils: 55 percent Urban land. 30 percent Minorcomponents: 4 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Coburg Setting Landform: Stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across -slope shape: Linear Parent material. Loamy alluvium over clayey alluvium Typical profile H1 - 0 to 18 inches. silty clay loam H2 - 18 to 53 inches: silty clay H3-53 to 65 inches: fine sandy loam Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Moderately well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 in/hr) Depth to watertable: About 18 to 30 inches Fraquencyofflooding: None Frequencyofponding. None Available water storage in profile: High (about 11.0 inches) Interpretive groups Lard capability classification (irrigated): 2w Lard capability classification (nonirrigated): 2w Hydrologic Soil Group: C Forage suitability group: Moderately Well Drained < 15% Slopes (G002XY0040R) Hydric soil rating. No LSM Natural Resources Wieb Soil Survey 1/11/2020 irk Conservation Serves National Cooperative Soil Survey Pagel oft Map Unit Description: Coburg -Urban land canplex--Lane County Area, Oregon Description of Urban Land Interpretive groups Land capability classification (irrigated): None specified Lard capability classification (nonirrigated): 8 Hydric sal rating. No Minor Components Conser Percent of map unit: 4 percent Landform: Stream terraces Hydric sal rating. Yes Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 16, Sep 10, 2019 LSM Natural Resources Mb Soil Survey 1/13= 211 Conservation Service National Cooperative Soil Survey Page 2 ort Map Unit Description: Courtney gravelly silty day loam, 0 to 3percent slopes --Lane County Area, Oregon Lane County Area, Oregon 2224A—Courtney gravelly silty clay loam, 0 to 3 percent slopes Map Unit Setting National map unit symbol. 2xpsh Elevation. 160 to 800 feet Mean annual precipitation: 39 to 59 inches Mean annual air temperature: 50 to 54 degrees F Frost -free period. 165 to 210 days Farmland classification. Farm land of statewide importance Map Unit Composition Courtney and similar soils. 85 percent Minorcomponents: 12 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Courtney Setting Landform: Drainageways on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear, concave Across -slope shape: Concave Parent material. Alluvium Typical profile Al - O to 8 inches: gravelly silty clay loam A2 - 8 to 17 inches: gravelly silty clay loam 2Btgl -17to 24 inches: gravelly clay 2Btg2 - 24 to 33 inches: gravelly clay 3Cg- 33 to 48 inches. very gravelly clay loam 4C - 48 to 60 inches: extremely gravelly sand Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: 10 to 19 inches to abrupt textural change Natural drainage class: Poorly drained Capacity of the most limiting layer to transmit water(Ksat): Very low to moderately low (0.00 to 0.01 in/hr) Depth to water table: About Oinches Frequencyofflooding: None Frequencyofponding. Frequent Available water storage in profile: Very low (about 2.5 inches) Interpretive groups Land capability classification (irrigated): 4w Land capability classification (nonirrigated): 4w Hydrologic Soil Group: D LSDA Natural Resources Web Soil Survey 1/92020 i Conservation Serves National Cooperative Soil Survey Pagel oft Map Unit Description: Courtney gravelly silty day loam, 0 to 3percent slopes --Lane County Area, Oregon Forage suitability group: Poorly Drained (G002XYOO6OR) Hydnc soil rating. Yes Minor Components Awbrig Percent of map unit: 6 percent Landform: Drainageways on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across -slope shape: Concave Hydric soil rating. Yes Bashaw Percent of map unit: 4 percent Landform: Depressions on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Concave Across -slope shape: Concave Hydric soil rating. Yes Conser Percent of map unit: 2 percent Landform: Depressions on stream terraces Landform position (three-dimensional): Tread Down-slope shape: Concave Across -slope shape: Concave Hydric soil rating. Yes Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 16, Sep 10, 2019 LSDA Natural Resources Mb Soil Survey 1/92020 i Conservation Serves National Cooperative Soil Survey Page 2 oft Map Unit Description: Nekia silty clay loam, 30 to 50 percent slopes—Lane County Area.. Oregon Lane County Area, Oregon 89F—Nekia silty clay loam, 30 to 50 percent slopes Map Unit Setting National map unit symbol. 239k Elevation. 350 to 1,400 feet Mean annual precipitation: 40 to 60 inches Mean annual airtempemture: 52 to 54 degrees F Frost -free period. 165 to 210 days Farmland classification. Not prime farmland Map Unit Composition Nekia and similar soils: 85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Nekia Setting Landform: Hills Landform position (two-dimensional/: Backslope, shoulder Landform position (three-dimensional): Side slope, nose slope Down-slope shape: Linear Across -slope shape: Linear Parent material. Colluvium and residuum derived from basalt and tuff Typical profile Oi-Oto 1 inches. slightly decomposed plant material H1 - 1 to 11 inches: silty clay loam H2 - 11 to 36 inches. clay H3 - 36 to 40 inches: unweathered bedrock Properties and qualities Slope: 30 to 50 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Natural drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksatl: Moderately high (0.20 to 0.57 in/hr) Depth to water table: More than 80 inches Frequencyofflooding: None Frequencyofponding. None Available water storage in profile: Low (about 5.7 inches) Interpretive groups Lard capability classification (irrigated): None specified Lard capability classification (nonirrigated): 6e Hydrologic Soil Group: C LSDA Natural Resources Web Soil Survey 1/92020 i conservation Serves National Cooperative Soil Survey Page 1 ort Map Unit Description: Nekia silty clay loam, 30 to 50 percent slopes --lane County Nee, Oregon Hydric soil rating: No Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 16, Sep 10, 2019 LSDA Natural Resources Web Soil Survey 1/92020 i Conservation Serme National Cooperative Soil Survey Page 2 oft /_1»:1k,IQKa-� HydroCAD Report 5S Existing O South Rooft and / 4S 16S Street R orth Impervious Sout Complex Drive ay and Roofs 24S 1P North Buildings "/ALE 14 ---- t� ZSR SWALE 1 Old Castle Vault 4' Stormcapture Modules (new Reach) SUbcat Reach on Link Routing Diagram for Design Prepared by Microsoft, Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 0 W18 HydroCAD Software Solutions LLC Design Type IA 24 -hr 2 yr Rainfall=3.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Pace 2 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points x 2 Runoff by SBUH method, Split Pervious/Imperv. Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 4S: South Complex Runoff Area=8,300 sf 100.00%Impervious Runoff Depth>2.46" Tc=5.0 min CN=0/98 Runoff=0.15 cfs 0.039 of Subcatchment 5S: Existing Runoff Area=18,200 sf 0.00% Impervious Runoff Depth>1.86" Tc=10.0 min CN=89/0 Runoff=0.22 ofs 0.065 of Subcatchment 165: North Impervious Runoff Area=7,300 sf 100.00%Impervious Runoff Depth>2.46" Tc=5.0 min CN=0/98 Runoff=0.13 cfs 0.034 of Subcatchment 245: North Buildings Runoff Area=1,000 sf 100.00%Impervious Runoff Depth>2.46" Tc=5.0 min CN=0/98 Runoff=0.02 cfs 0.005 of Subcatchment B3: South Rooftops and Runoff Area=6,600 sf 100.00%Impervious Runoff Depth>2.46" Tc=10.0 min CN=0/98 Runoff=0.11 cfs 0.031 at Reach 2511: (new Reach) Inflow=0.11 cis 0.078 at Outflow=0.11 cis 0.078 at Pond 1 P: SWALE Peak EIev=514.80' Storage=1,147 cf Inflow=0.39 cfs 0.104 at Outflow=0.37 cis 0.081 at Pond 14P: 1 Old Castle Vault 4' Stormcapture Peak EIev=508.35' Storage=703 cf Inflow=0.37 cfs 0.081 at Outflow=0.11 ds 0.078 at Pond 23P: SWALE Peak EIev=513.77' Storage=205 cf Inflow=0.02 cfs 0.005 at Outflow=0.00 cfs 0.000 of Design Type IA 24 -hr 2 yr Rainfall=3.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 3 Summary for Subcatchment 4S: South Complex Driveway and Roofs Runoff = 0.15 cfs @ 7.90 hrs, Volume= 0.039 af, Depth> 2.46" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 2 yr Rainfall=3.30" 8,300 98 Paved parking, HSG C 8,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: Existing Runoff = 0.22 cfs @ 7.99 hrs, Volume- 0.065 af, Depth> 1.86" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 2 yr Rainfall=3.30" Area (sf) CN Description * 9,400 90 Previous Wetland 18,200 89 Weighted Average 18,200 89 100.00% Pervious Area Tc Length Slope Velocity Capacity Description Direct Entry, Summary for Subcatchment 16S: North Impervious Runoff = 0.13 cfs @ 7.90 hrs, Volurne- 0.034 af, Depth> 2.46" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 2 yr Rainfall=3.30" Area (sf) CN Description 7,300 98 Paved parking, HSG C 7,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Design Type IA 24 -hr 2 yr Rainfall=3.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 4 Summary for Subcatchment 24S: North Buildings Runoff = 0.02 cfs @ 7.90 hrs, Volume- 0.005 af, Depth> 2.46" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 2 yr Rainfall=3.30" 1,000 98 Paved parking, HSG C 1,000 98 100.00% Impervious Area Tc Length Description 5.0 Direct Entry, Summary for Subcatchment 133: South Rooftops and Street ROW Runoff = 0.11 cfs @ 7.98 hrs, Volume= 0.031 af, Depth> 2.46" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 2 yr Rainfall=3.30" Area (sf) CN Description 2,100 98 Roofs, HSG C 4,500 98 Paved parking, HSG C 6,600 98 Weighted Average 6,600 98 100.00% Impervious Area Tc Length Description Entry, Summary for Reach 25R: (new Reach) Inflow Area = 0.533 ac,100.00% Impervious, Inflow Depth > 1.75" for 2 yr event Inflow = 0.11 cfs @ 9.38 hrs, Volume= 0.078 of Outflow = 0.11 cfs @ 9.38 hrs, Volume= 0.078 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Summary for Pond 1 P: SWALE Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth > 2.46" for 2 yr event Inflow = 0.39 cfs @ 7.92 hrs, Volume= 0.104 of Outflow = 0.37 cfs @ 8.02 hrs, Volume= 0.081 at, Atten= 4%, Lag= 5.8 min Primary = 0.37 cfs @ 8.02 hrs, Volume= 0.081 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Design Type IA 24 -hr 2 yr Rainfall=3.30" Prepared by Microsoft Printed 6/30/2020 HydroCADO 10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 5 Peak Elev= 514.80'@ 8.02 hrs Surf.Area= 1,153 sf Storage= 1,147 of Plug -Flow detention time= 185.7 min calculated for 0.081 of (770% of inflow) Center -of -Mass det. time= 76.8 min ( 723.9 - 647.1 ) Volume Invert Avail.Storaae Storage Description #1 513.00' 1,395 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 513.00 125 0 0 515.00 1,270 1,395 1,395 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.37 cfs @ 8.02 hrs HW=514.79' TW=506.29' (Dynamic Tailwater) L741harp-Crested Rectangular Weir (Weir Controls 0.37 cfs @ 1.29 fps) Summary for Pond 14P: 1 Old Castle Vault 4' Stormcapture Modules Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth > 1.91" for 2 yr event Inflow = 0.37 cfs @ 8.02 hrs, Volume= 0.081 of Outflow = 0.11 cfs @ 9.38 hrs, Volume= 0.078 af, Atten= 71%, Lag= 81.7 min Primary = 0.11 cfs @ 9.38 hrs, Volume= 0.078 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 508.35'@9.38 hrs Surf.Area= 210 sf Storage= 703 cf Plug -Flow detention time= 83.4 min calculated for 0.078 of (96% of inflow) Center -of -Mass det. time= 63.4 min ( 787.3 - 723.9) Volume Invert Avail.Storage Storage Description #1 505.00' 1,260 of 7.00'W x 15.001 x 6.00'H OldCastle Facility x 2 Device Routing Invert Outlet Devices #1 Primary 505.00' 6.0" Round Culvert L= 37.1' RCP, sq.cut end projecting, Ke= 0.500 Inlet/ Outlet Invert= 505.00'/ 504.50' S=0.01357' Cc= 0.900 n= 0.010, Flow Area= 0.20 sf #2 Device 1 505.00' 1.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 510.60' 6.0" Horiz. Orifice/Grate C=0.600 Limited to weir flow at low heads Primary OutFlow Max=0.11 cfs @ 9.38 hrs HW=508.35' TW=0.00' (Dynamic Tailwater) t1=Culvert (Passes 0.11 cfs of 1.60 cfs potential flow) 1 2=Orifice/Grate (Orifice Controls 0.11 cfs @ 8.73 fps) 3=Orifice/Grate ( Controls 0.00 cfs) Design Type IA 24 -hr 2 yr Rainfall=3.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD@ 10.00-24 s/n 10784 02018 HydroCAD Software Solutions LLC Paae 6 Summary for Pond 23P: SWALE Inflow Area = 0.023 ac,100.00% Impervious, Inflow Depth > 2.46" for 2 yr event Inflow = 0.02 cfs @ 7.90 hrs, Volume= 0.005 of Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 513.77'@ 20.00 hrs Surf.Area= 451 sf Storage= 205 cf Plug -Flow detention time= (not calculated: initial storage exceeds outtlow) Center -of -Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 513.00' 660 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 513.00 80 0 0 514.50 800 660 660 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=513.00' TW=0.00' (Dynamic Tailwater) L7 -Sharp -Crested Rectangular Weir ( Controls 0.00 cfs) Design Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 7 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points x 2 Runoff by SBUH method, Split Pervious/Imperv. Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 4S: South Complex Runoff Area=8,300 sf 100.00%Impervious Runoff Depth>3.23" Tc=5.0 min CN=0/98 Runoff=0.19 cis 0.051 of Subcatchment 5S: Existing Runoff Area=18,200 sf 0.00% Impervious Runoff Depth>2.64" Tc=10.0 min CN=89/0 Runoff=0.32 cfs 0.092 of Subcatchment 165: North Impervious Runoff Area=7,300 sf 100.00%Impervious Runoff Depth>3.23" Tc=5.0 min CN=0/98 Runoff=0.17 cfs 0.045 of Subcatchment 245: North Buildings Runoff Area=1,000 sf 100.00%Impervious Runoff Depth>3.23" Tc=5.0 min CN=0/98 Runoff=0.02 cfs 0.006 of Subcatchment B3: South Rooftops and Runoff Area=6,600 sf 100.00%Impervious Runoff Depth>3.23" Tc=10.Omin CN=0/98 Runoff=0.15cfs 0.041 of Reach 2511: (new Reach) Inflow=0.14 cfs 0.107 of Outflow=0.14 ds 0.107 of Pond 1P: SWALE Peak Elev=514.83'Storage=1,184 cf Inflow=0.51 cis 0.137 of Outflow=0.50 cfs 0.114 of Pond 14P: 1 Old Castle Vault 4' Peak EIev=510.59' Storage=1,173 cf Inflow=0.50 cfs 0.114 of Outflow=0.14 cfs 0.107 of Pond 23P: SWALE Peak EIev=513.90' Storage=269 cf Inflow=0.02 cfs 0.006 of Outflow=0.00 cfs 0.000 of Design Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 8 Summary for Subcatchment 4S: South Complex Driveway and Roofs Runoff = 0.19 cfs @ 7.90 hrs, Volume= 0.051 af, Depth> 3.23" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 10 yr Rainfall=4.30" 8,300 98 Paved parking, HSG C 8,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: Existing Runoff = 0.32 cfs @ 7.99 hrs, Volume- 0.092 af, Depth> 2.64" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) CN Description * 9,400 90 Previous Wetland 18,200 89 Weighted Average 18,200 89 100.00% Pervious Area Tc Length Slope Velocity Capacity Description Summary for Subcatchment 16S: North Impervious Runoff = 0.17 cfs @ 7.90 hrs, Volume= 0.045 af, Depth> 3.23" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) CN Description 7,300 98 Paved parking, HSG C 7,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Design Type lA 24 -hr 10 yr Rainfall=4.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 9 Summary for Subcatchment 24S: North Buildings Runoff = 0.02 cfs@ 7.90 hrs, Volume- 0.006 af, Depth> 3.23" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 10 yr Rainfall=4.30" 1,000 98 Paved parking, HSG C 1,000 98 100.00% Impervious Area Tc Length Description 5.0 Direct Entry, Summary for Subcatchment 133: South Rooftops and Street ROW Runoff = 0.15 cfs @ 7.98 hrs, Volume= 0.041 af, Depth> 3.23" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 10 yr Rainfall=4.30" Area (sf) CN Description 2,100 98 Roofs, HSG C 4,500 98 Paved parking, HSG C 6,600 98 Weighted Average 6,600 98 100.00% Impervious Area Tc Length Description Entry, Summary for Reach 25R: (new Reach) Inflow Area = 0.533 ac,100.00% Impervious, Inflow Depth > 2.41" for 10 yr event Inflow = 0.14 cfs @ 9.39 hrs, Volume= 0.107 of Outflow = 0.14 cfs @ 9.39 hrs, Volume= 0.107 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Summary for Pond 1 P: SWALE Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth > 3.23" for 10 yr event Inflow = 0.51 cfs @ 7.92 hrs, Volume= 0.137 of Outflow = 0.50 cfs @ 7.99 hrs, Volume= 0.114 af, Atten= 2%, Lag= 4.2 min Primary = 0.50 cfs @ 7.99 hrs, Volume= 0.114 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Design Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by Microsoft Printed 6/30/2020 HydroCADO 10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 10 Peak Elev= 514.83'@7.99 hrs Surf.Area= 1,171 sf Storage= 1,184 cf Plug -Flow detention time= 146.4 min calculated for 0.113 of (82 /. of inflow) Center -of -Mass det. time= 59.7 min ( 705.6 - 645.9) Volume Invert Avail.Storaae Storage Description #1 513.00' 1,395 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 513.00 125 0 0 515.00 1,270 1,395 1,395 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.50 cfs @ 7.99 hrs HW=514.83' TW=507.77' (Dynamic Tailwater) L741harp-Crested Rectangular Weir (Weir Controls 0.50 cfs @ 1.43 fps) Summary for Pond 14P: 1 Old Castle Vault 4' Stormoepture Modules Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth > 2.67" for 10 yr event Inflow = 0.50 cfs @ 7.99 hrs, Volume= 0.114 of Outflow = 0.14 cfs @ 9.39 hrs, Volume= 0.107 af, Atten= 72 %, Lag= 83.8 min Primary = 0.14 cfs @ 9.39 hrs, Volume= 0.107 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 510.59'@9.39 hrs Surf.Area= 210 sf Storage= 1,173 cf Plug -Flow detention time= 109.0 min calculated for 0.107 of (94%, of inflow) Center -of -Mass det. time= 81.7 min ( 787.3 - 705.6) Volume Invert Avail.Storage Storage Description #1 505.00' 1,260 cf 7.00'W x 15.001 x 6.00'H OldCastle Facility x 2 Device Routing Invert Outlet Devices #1 Primary 505.00' 6.0" Round Culvert L= 37.1' RCP, sq.cut end projecting, Ke= 0.500 Inlet/ Outlet Invert= 505.00'/ 504.50' S=0.01357' Cc= 0.900 n= 0.010, Flow Area= 0.20 sf #2 Device 1 505.00' 1.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 510.60' 6.0" Horiz. Orifice/Grate C=0.600 Limited to weir flow at low heads Primary OutFlow Max=0.14 cfs @ 9.39 hrs HW=510.59' TW=0.00' (Dynamic Tailwater) t1=Culvert (Passes 0.14 cfs of 2.07 cfs potential flow) 1 2=Orifice/Grate (Orifice Controls 0.14 cfs @ 11.32 fps) 3=Orifice/Grate ( Controls 0.00 cfs) Design Type IA 24 -hr 10 yr Rainfall=4.30" Prepared by Microsoft Printed 6/30/2020 HydroCAD010.00-24 s/n 10784 02018 HydroCAD Software Solutions LLC Paae 11 Summary for Pond 23P: SWALE Inflow Area = 0.023 ac,100.00% Impervious, Inflow Depth > 3.23" for 10 yr event Inflow = 0.02 cfs @ 7.90 hrs, Volume= 0.006 of Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 513.90'@20.00 hrs Surf.Area= 514 sf Storage= 269 cf Plug -Flow detention time= (not calculated: initial storage exceeds outtlow) Center -of -Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 513.00' 660 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 513.00 80 0 0 514.50 800 660 660 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=513.00' TW=0.00' (Dynamic Tailwater) L7 -Sharp -Crested Rectangular Weir ( Controls 0.00 cfs) Design Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 12 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points x 2 Runoff by SBUH method, Split Pervious/Imperv. Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 4S: South Complex Runoff Area=8,300 sf 100.00%Impervious Runoff Depth>3.61" Tc=5.0 min CN=0/98 Runoff=0.22 cfs 0.057 of Subcatchment 5S: Existing Runoff Area=18,200 sf 0.00% Impervious Runoff Depth>3.04" Tc=10.0 min CN=89/0 Runoff=0.37 cfs 0.106 of Subcatchment 165: North Impervious Runoff Area=7,300 sf 100.00%Impervious Runoff Depth>3.61" Tc=5.0 min CN=0/98 Runoff=0.19 cfs 0.050 of Subcatchment 245: North Buildings Runoff Area=1,000 sf 100.00%Impervious Runoff Depth>3.61" Tc=5.0 min CN=0/98 Runoff=0.03 cfs 0.007 of Subcatchment B3: South Rooftops and Runoff Area=6,600 sf 100.00%Impervious Runoff Depth>3.62" Tc=10.0 min CN=0/98 Runoff=0.16 cfs 0.046 of Reach 2511: (new Reach) Inflow=0.29 ds 0.122 of Outflow=0.29 ds 0.122 of Pond 1 P: SWALE Peak Elev=514.84' Storage=1,200 cf Inflow=0.57 cfs 0.153 of Outflow=0.56 cfs 0.130 of Pond 14P: 1 Old Castle Vault 4' Peak EIev=510.70' Storage=1,196 cf Inflow=0.56 cfs 0.130 of Outflow=0.29 ds 0.122 of Pond 23P: SWALE Peak EIev=513.97' Storage=301 cf Inflow=0.03 ds 0.007 of Outflow=0.00 cfs 0.000 of Design Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 13 Summary for Subcatchment 4S: South Complex Driveway and Roofs Runoff = 0.22 cfs @ 7.90 hrs, Volume= 0.057 af, Depth> 3.61" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 25 yr Rainfall=4.80" 8,300 98 Paved parking, HSG C 8,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: Existing Runoff = 0.37 cfs @ 7.98 hrs, Volume- 0.106 af, Depth> 3.04" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (sf) CN Description * 9,400 90 Previous Wetland 18,200 89 Weighted Average 18,200 89 100.00% Pervious Area Tc Length Slope Velocity Capacity Description Direct Entry, Summary for Subcatchment 16S: North Impervious Runoff = 0.19 cfs@ 7.90 hrs, Volurne- 0.050 af, Depth> 3.61" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (sf) CN Description 7,300 98 Paved parking, HSG C 7,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Design Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 14 Summary for Subcatchment 24S: North Buildings Runoff = 0.03 cfs@ 7.90 hrs, Volume- 0.007 af, Depth> 3.61" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 25 yr Rainfall=4.80" 1,000 98 Paved parking, HSG C 1,000 98 100.00% Impervious Area Tc Length Description 5.0 Direct Entry, Summary for Subcatchment 133: South Rooftops and Street ROW Runoff = 0.16 cfs @ 7.98 hrs, Volume= 0.046 af, Depth> 3.62" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr 25 yr Rainfall=4.80" Area (sf) CN Description 2,100 98 Roofs, HSG C 4,500 98 Paved parking, HSG C 6,600 98 Weighted Average 6,600 98 100.00% Impervious Area Tc Length Description Entry, Summary for Reach 25R: (new Reach) Inflow Area = 0.533 ac,100.00% Impervious, Inflow Depth > 2.74" for 25 yr event Inflow = 0.29 cfs @ 8.47 hrs, Volume= 0.122 of Outflow = 0.29 cfs @ 8.47 hrs, Volume= 0.122 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Summary for Pond 1 P: SWALE Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth > 3.61" for 25 yr event Inflow = 0.57 cfs @ 7.92 hrs, Volume= 0.153 of Outflow = 0.56 cfs @ 7.99 hrs, Volume= 0.130 af, Atten= I%, Lag= 4.1 min Primary = 0.56 cfs @ 7.99 hrs, Volume= 0.130 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Design Type IA 24-hr 25 yr Rainfall=4.80" Prepared by Microsoft Printed 6/30/2020 HydroCADO 10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Pace 15 Peak Elev= 514.84'@ 7.99 hrs Surf.Area= 1,179 sf Storage= 1,200 cf Plug-Flow detention time= 133.2 min calculated for 0.130 of (84%, of inflow) Center-of-Mass det. time= 54.0 min (699.5 - 645.5) Volume Invert Avail.Storage Storage Description #1 513.00' 1,395 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 513.00 125 0 0 515.00 1,270 1,395 1,395 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp-Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.56 cfs @ 7.99 hrs HW=514.84' TW=508.51' (Dynamic Tailwater) L741harp-Crested Rectangular Weir (Weir Controls 0.56 cfs @ 1.49 fps) Summary for Pond 14P: 1 Old Castle Vault 4' Stormoepture Modules Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth > 3.05" for 25 yr event Inflow = 0.56 cfs @ 7.99 hrs, Volume= 0.130 of Outflow = 0.29 cfs @ 8.47 hrs, Volume= 0.122 af, Atten= 47%, Lag= 28.7 min Primary = 0.29 cfs @ 8.47 hrs, Volume= 0.122 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 510.70'@8.47 hrs Surf.Area= 210 sf Storage= 1,196 cf Plug-Flow detention time= 107.8 min calculated for 0.121 of (930% of inflow) Center-of-Mass det. time= 77.2 min ( 776.7 - 699.5) Volume Invert Avail.Storage Storage Description #1 505.00' 1,260 cf 7.00'W x 15.001 x 6.00'H OldCastle Facility x 2 Device Routing Invert Outlet Devices #1 Primary 505.00' 6.0" Round Culvert L= 37.1' RCP, sq.cut end projecting, Ke= 0.500 Inlet/ Outlet Invert= 505.00'/ 504.50' S=0.01357' Cc= 0.900 n= 0.010, Flow Area= 0.20 sf #2 Device 1 505.00' 1.5" Vert. Orifice/Grate C=0.600 #3 Device 1 510.60' 6.0" Horiz. Orifice/Grate C=0.600 Limited to weir flow at low heads Primary OutFlow Max=0.28 cfs @ 8.47 hrs HW=510.69' TW=0.00' (Dynamic Tailwater) t1=Culvert (Passes 0.28 cfs of 2.09 cfs potential flow) 1 2=Orifice/Grate (Orifice Controls 0.14 cfs @ 11.42 fps) 3=Orifice/Grate (Weir Controls 0.14 cfs @ 0.99 fps) Design Type IA 24 -hr 25 yr Rainfall=4.80" Prepared by Microsoft Printed 6/30/2020 HydroCAD@ 10.00-24 s/n 10784 02018 HydroCAD Software Solutions LLC Paae 16 Summary for Pond 23P: SWALE Inflow Area = 0.023 ac,100.00% Impervious, Inflow Depth > 3.61" for 25 yr event Inflow = 0.03 cfs @ 7.90 hrs, Volume= 0.007 of Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 513.97'@ 20.00 hrs Surf.Area= 543 sf Storage= 301 cf Plug -Flow detention time= (not calculated: initial storage exceeds outtlow) Center -of -Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 513.00' 660 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 513.00 80 0 0 514.50 800 660 660 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=513.01' TW=0.00' (Dynamic Tailwater) L7 -Sharp -Crested Rectangular Weir ( Controls 0.00 cfs) Design Type IA 24 -hr WO Rainfall=0.83" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 17 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points x 2 Runoff by SBUH method, Split Pervious/Imperv. Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 4S: South Complex Runoff Area=8,300 sf 100.00%Impervious Runoff Depth>0.53" Tc=5.0 min CN=0/98 Runoff=0.03 cfs 0.008 of Subcatchment 5S: Existing Runoff Area=18,200 sf 0.00% Impervious Runoff Depth>0.15" Tc=10.0 min CN=89/0 Runoff=0.01 cfs 0.005 of Subcatchment 165: North Impervious Runoff Area=7,300 sf 100.00%Impervious Runoff Depth>0.53" Tc=5.0 min CN=0/98 Runoff=0.03 cfs 0.007 of Subcatchment 245: North Buildings Runoff Area=1,000 sf 100.00%Impervious Runoff Depth>0.53" Tc=5.0 min CN=0/98 Runoff=0.00 cis 0.001 of Subcatchment B3: South Rooftops and Runoff Area=6,600 sf 100.00%Impervious Runoff Depth>0.53" Tc=10.0 min CN=0/98 Runoff=0.02 cfs 0.007 of Reach 2511: (new Reach) Inflow=0.00 ds 0.000 of Outflow=0.00 cfs 0.000 at Pond 1 P: SWALE Peak Elev=514.65' Storage=983 cf Inflow=0.08 cfs 0.023 at Outflow=0.00 cfs 0.000 at Pond 14P: 1 Old Castle Vault 4' Stormcapture Peak Elev=505.00' Storage=0 cf Inflow=0.00 cfs 0.000 at Outflow=0.00 cfs 0.000 at Pond 23P: SWALE Peak Elev=513.29' Storage=44cf Inflow=0.00cfs 0.001 at Outflow=0.00 cfs 0.000 of Design Type /A 24 -hr WO Rainfall=0.83" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 18 Summary for Subcatchment 4S: South Complex Driveway and Roofs Runoff = 0.03 cfs @ 7.93 hrs, Volume- 0.008 af, Depth> 0.53" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr WO Rainfall=0.83" 8,300 98 Paved parking, HSG C 8,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: Existing Runoff = 0.01 cfs @ 8.06 hrs, Volume- 0.005 af, Depth> 0.15" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr WO Rainfall=0.83" Area (sf) CN Description * 9,400 90 Previous Wetland 18,200 89 Weighted Average 18,200 89 100.00% Pervious Area Tc Length Slope Velocity Capacity Description Direct Entry, Summary for Subcatchment 16S: North Impervious Runoff = 0.03 cfs @ 7.93 hrs, Volume- 0.007 af, Depth> 0.53" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr WO Rainfall=0.83" Area (sf) CN Description 7,300 98 Paved parking, HSG C 7,300 98 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Design Type /A 24 -hr WO Rainfall=0.83" Prepared by Microsoft Printed 6/30/2020 HydroCAD®10.00-24 s/n 10784 © 2018 HydroCAD Software Solutions LLC Paae 19 Summary for Subcatchment 24S: North Buildings Runoff = 0.00 cfs@ 7.93 hrs, Volume- 0.001 af, Depth> 0.53" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr WO Rainfall=0.83" 1,000 98 Paved parking, HSG C 1,000 98 100.00% Impervious Area Tc Length 5.0 Runoff = Description Entry, Summary for Subcatchment 133: South Rooftops and Street ROW 0.02 cfs @ 7.98 hrs, Volume= 0.007 af, Depth> 0.53" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type IA 24 -hr WO Rainfall=0.83" Area (sf) CN Description 2,100 98 Roofs, HSG C 4,500 98 Paved parking, HSG C 6,600 98 Weighted Average 6,600 98 100.00% Impervious Area Tc Length Description Entry, Summary for Reach 25R: (new Reach) Inflow Area = 0.533 ac,100.00% Impervious, Inflow Depth= 0.00" for WO event Inflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Slor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Summary for Pond 1 P: SWALE Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth > 0.53" for WO event Inflow = 0.08 cfs @ 7.95 hrs, Volume= 0.023 of Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Design Type IA 24 -hr NO Rainfall=0.83" Prepared by Microsoft Printed 6/30/2020 HydroCADO 10.00-24 s/n 10784 02018 HydroCAD Software Solutions LLC Paae 20 Peak Elev= 514.65'@20.00 hrs Surf.Area= 1,068 sf Storage= 983 cf Plug -Flow detention time= (not calculated: initial storage exceeds outflow) Center -of -Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 513.00' 1,395 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 513.00 125 0 0 515.00 1,270 1,395 1,395 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=513.01' TW=505.00' (Dynamic Tailwater) L741harp-Crested Rectangular Weir ( Controls 0.00 cfs) Summary for Pond 14P: 1 Old Castle Vault 4' Stormcapture Modules Inflow Area = 0.510 ac,100.00% Impervious, Inflow Depth = 0.00" for WO event Inflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 505.00'@5.00 hrs Surf.Area= 210 sf Storage= 0 cf Plug -Flow detention time= (not calculated: initial storage exceeds outflow) Center -of -Mass det. time= (not calculated: no inflow) Volume Invert Avail.Storage Storage Description #1 505.00' 1,260 cf 7.00'W x 15.001 x 6.00'H OldCastle Facility x 2 Device Routing Invert Outlet Devices #1 Primary 505.00' 6.0" Round Culvert L= 37.1' RCP, sq.cut end projecting, Ke= 0.500 Inlet/ Outlet Invert= 505.00'/ 504.50' S=0.01357' Cc= 0.900 n= 0.010, Flow Area= 0.20 sf #2 Device 1 505.00' 1.5" Vert. Orifice/Grate C=0.600 #3 Device 1 510.60' 6.0" Horiz. Orifice/Grate C=0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=505.00' TW=0.00' (Dynamic Tailwater) t-1 =Culvert ( Controls 0.00 cfs) 1 2=Orifioe/Grate ( Controls 0.00 cfs) 3=Orifioe/Grate ( Controls 0.00 cfs) Design Type IA 24 -hr NO Rainfall=0.83" Prepared by Microsoft Printed 6/30/2020 HydroCAD@ 10.00-24 s/n 10784 02018 HydroCAD Software Solutions LLC Paae 21 Summary for Pond 23P: SWALE Inflow Area = 0.023 ac,100.00% Impervious, Inflow Depth > 0.53" for WO event Inflow = 0.00 cfs @ 7.93 hrs, Volume= 0.001 of Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 513.29'@ 20.00 hrs Surf.Area= 221 sf Storage= 44 cf Plug -Flow detention time= (not calculated: initial storage exceeds outtlow) Center -of -Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 513.00' 660 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 513.00 80 0 0 514.50 800 660 660 Device Routing Invert Outlet Devices #1 Primary 514.65' 2.0' long x 1.00' rise Sharp -Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=513.00' TW=0.00' (Dynamic Tailwater) L7 -Sharp -Crested Rectangular Weir ( Controls 0.00 cfs)