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Studies Applicant 4/2/2024
Preliminary Stormwater Report Rosboro Mill Expansion Prepared for: Rosboro Prepared by: Randi Rondeau, EIT Project Engineer: Wyatt Morris, PE March 2024 | KPFF Project #2300348 KPFF’S COMMITMENT TO SUSTAINABILITY As a member of the US Green Building Council, a sustaining member of Oregon Natural Step, and a member of the Sustainable Products Purchasers Coalition, KPFF is committed to the practice of sustainable design and the use of sustainable materials in our work. When hardcopy reports are provided by KPFF, they are prepared using recycled and recyclable materials, reflecting KPFF’s commitment to using sustainable practices and methods in all of our products. 1 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Table of Contents Project Overview and Description ..................................................................................................................... 3 Project Size and Location ............................................................................................................................... 3 Existing vs. Proposed Conditions .................................................................................................................... 3 Project Narrative ................................................................................................................................................ 4 Proposed Stormwater System ........................................................................................................................ 4 Analysis ............................................................................................................................................................... 7 Engineering Conclusions .................................................................................................................................... 8 Tables and Figures TABLE 1: Existing Conditions Composite Curve Number (CCN) Analysis ........................................................... 6 TABLE 2: Proposed Conditions Composite Curve Number (CCN) Analysis ........................................................ 6 TABLE 3: 24-Hour Precipitation for Springfield, OR ........................................................................................... 7 TABLE 4: Catchment and Facility Table .............................................................................................................. 7 2 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendices Appendix 1 Basin Maps Appendix 2 Stormwater Plans Appendix 3 Analysis Calculations Appendix 4 Contech CDS Hydrodynamic Separator Documentation Appendix 5 Current Rosboro Testing Appendix 6 Geotechnical Report Appendix 7 O&M Report 3 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Project Overview and Description Project Size and Location The Rosboro Mill Expansion Project will take place on approximately 12.25 acres of the existing 71-acre Rosboro Mill campus along South A and Main Streets in Springfield, Oregon. The project is bound by South A Street, Main Street, commercial and industrial developments to the north, South 28th Street to the east, industrial developments to the west and railway to the south. The project introduces two new buildings to improve mill operations and includes additional site circulation and parking. Watershed and Soil Description Springfield’s stormwater basins are part of the larger Upper Willamette Basin. The site itself is located within the City of Springfield’s Millrace Basin, per the City’s 2010 Stormwater Management Plan and City of Springfield GIS mapping. The proposed stormwater improvements connect to the City’s stormwater system. The site discharge point is at the west end of the site and the destination downstream is the Springfield Millrace Ponds, leading into the Willamette River. Geotechnical investigations were conducted on the project site to determine existing site conditions. The site has been identified as having the majority of Type C soils with deep clay layers ranging from ~8.5 to 14.5 feet deep. City Stormwater Code 4.3.110 Section D states that site constraints, such as the clay layers on this project site, demonstrate the technical infeasibility of infiltrating runoff. Therefore, stormwater runoff infiltration will not be feasible for this project site and mechanical treatment is being proposed. See Appendix 6 for the full Geotechnical Report. Existing vs. Proposed Conditions Existing Conditions Currently the site is a fully developed and functional industrial mill. There are multiple operational mill facilities and kilns on site as well as additional storage and laydown areas designated for the facility to function efficiently. The current site has compliant stormwater controls to meet the active 1200 -Z DEQ Permit. This permit allows the site to operate multiple site stormwater discharges to the City of Springfield public stormwater system. See Appendix 5 for Documentation of Existing Plant Stormwater Testing Results. Proposed Conditions The project will include the improvement of campus operations and production through the removal of an existing building and varying structures including walls, sheds and hardscape and the introduction of two new buildings, additional site access and parking. These revisions are necessary to increase the glulam production for Rosboro. The project will treat site runoff according to the City design standards in Chapter 3, Water Quality. The stormwater runoff from the parking area east of the proposed Glulam Building will sheet flow to a vegetated filtration planter. The remaining area of the site will collect stormwater runoff through roof drains and catch basins and convey it to the mechanical treatment. The area drains and catch basins around the site collecting stormwater runoff will be primed and trapped to collect pollutants before entering the on- site storm system. The site has been identified by the City as not needing detention due to a minimal increase in runoff based on the composite curve number analysis. See the Flow Control section in this report for full analysis. 4 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT The proposed site includes approximately 12.25 acres of impervious area. Of this, 5.08 acres is from structures, 6.99 acres is from industrial storage, gravel areas and circulation pavement and 0.15 acres is from parking. Project Narrative The City of Springfield Development Code states that all new developments shall infiltrate the full water quality storm, newly identified as 1.4 inches of rainfall for the 24 -hour design storm. Due to site limitations, including deep clay layers discovered during geotechnical investigations (see Appendix 6) and limited available site area, an alternative treatment plan has been proposed. The City of Springfield has been receptive to this plan in discussions. Proposed Stormwater System The impervious area on-site is divided between building roof areas, asphalt parking, asphalt drive aisles and industrial storage and handling gravel areas. See Appendix 1 for Drainage Basin Areas. Mechanical treatment has been selected for water quality treatment, except for on-site asphalt parking, which will be treated by a vegetative planter. The remainder of the site, containing drive aisles, roof area and gravel storage areas, will be treated through a mechanical treatment structure. All facilities will be designed per the City of Springfield standards. The filtration planter will have 6 inches of open storage at the surface with a minimum of 2 inches of freeboard. The planter will have 18 inches of growing media with landscape planting for water quality management. There will also be a minimum of 12 inches of rock storage depth below the facility. The filtration planter will treat the water quality storm and an overflow structure will collect larger storm events to convey to the stormwater system. The mechanical treatment will be a hydrodynamic separator such as a Contech CDS and will treat the remaining new impervious area, consisting of the roof area and industrial storage/circulation area. This product will be sized and maintained per the manufacturer’s recommendation. The mechanical treatment proposed will consist of a sedimentation manhole to settle out the remaining larger sediment and debris paired with the hydrodynamic separator. To meet jurisdictional requirements put forth by the Washington State Department of Ecology, the hydrodynamic device has been tested and successfully achieved 80% removal of particles with a mean size of 125 microns. The sedimentation manhole and hydrodynamic separator will sufficiently remove solids from runoff and will fit into Rosboro’s current stormwater maintenance program for regular cleaning and inspection. Therefore, the revised basin will be treated entirely by the sedimentation manhole and hydrodynamic separator. See Appendix 4 for Supporting Documentation of the Hydrodynamic Separator Functionality from the manufacturer (Contech) and the Washington State Tape List. 5 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT On the Rosboro Campus, the revised basin for this project does not currently house any log storage or any other activity that has been flagged for monitoring by DEQ under the 1200-Z Permit. No pollution-generating activities are being proposed for this area. The log storage yards are typically the parts of these industrial sites that require more focused treatment. See Appendix 5 for Existing Stormwater Testing Documentation. Rosboro has robust protocols for vehicle-related spills or leaks and all catch basins proposed will be Gibson double chamber style, known for adequately retaining incidental spills. With those measures in place, no additional oil separation measures should be needed. Water Quality Facilities Basin 1A encompasses the Glulam building roof area. Runoff from buildings will be collected via roof drains and downspouts where it will connect to the on-site storm system. This runoff will be conveyed through the mechanical treatment structure and sedimentation manhole, then discharged into the City system at Manhole #50571. Basin 1B encompasses the asphalt parking east of the Glulam Building. Runoff from the parking area will sheet flow to a stormwater filtration planter adjacent to the pavement via curb cut. The planter will provide treatment via filtration and overflow runoff will be routed to the on-site storm system via an overflow inlet. The treated runoff will be conveyed to the on-site storm system where it will be conveyed through the mechanical treatment structure and sedimentation manhole, then to the connection manhole. Basin 1C encompasses the industrial paving and gravel storage areas adjacent to the Glulam Building. The runoff will sheet flow away from the building where it will be collected via catch basins . These catch basins will be primed and trapped to act as pre-treatment before the runoff is conveyed to the mechanical treatment structure and sedimentation manhole prior to the connection manhole. Basin 2A encompasses the Glulam building roof area. Runoff from buildings will be collected via roof drains and downspouts where it will connect to the on-site storm system. This runoff will be conveyed through the on-site system to the mechanical treatment structure and sedimentation manhole before the connection manhole. Basin 2B encompasses the industrial paving adjacent to the Planer Mill. The runoff will sheet flow away from the building where it will be collected via catch basins. These catch basins will be primed and trapped to act as pre-treatment before the runoff is conveyed through the on-site system to the mechanical treatment structure and the sedimentation manhole before the connection manhole. Flow Control Site area composite curve numbers were calculated to determine the impact of new impervious area on runoff from the site. From these calculations, it was determined that there would be an increase of less than 0.5 for the composite curve number. See Tables 1 and 2 for information regarding site areas and relative curve numbers. This indicates that the pre-construction and post-construction values for runoff are approximately the same, concluding that no downstream analysis or additional detention will be required per the City of Springfield. 6 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT TABLE 1: Existing Conditions Composite Curve Number (CCN) Analysis Existing Conditions Analysis TAX LOT TOTAL 300 401 100 -- AREA (SF) 342,310 260,881 3,066,014 3,669,205 Fair Condition Soil Area Curve Number: 80 16,909 18,440 139,828 175,177 Poor Condition Soil Area Curve Number: 84 47,645 89,152 272,187 408,984 Gravel Area Curve Number: 92 21,433 53,415 53,191 128,039 Paved/Roof Area Curve Number: 98 256,323 99,874 2,600,808 2,957,005 (CCN): 95.37 TABLE 2: Proposed Conditions Composite Curve Number (CCN) Analysis Proposed Conditions Analysis TAX LOT TOTAL 300 401 100 -- AREA (SF) 342,310 260,881 3,066,014 3,669,205 Fair Condition Soil Area Curve Number: 80 16,909 0 176,747 193,656 Poor Condition Soil Area Curve Number: 84 22,428 0 163,879 186,307 Gravel Area Curve Number: 92 47,952 105,132 123,797 276,881 Paved/Roof Area Curve Number: 98 255,021 266,459 2,601,591 3,012,361 (CCN): 95.89 Source Control Source control is required for facilities that are highly likely to generate pollutants that are not addressed through the implementation of vegetated stormwater facilities or mechanical treatment. All drainage within the building footprint will be captured by drains and basins within the building and will be conveyed to the sanitary sewer system to prevent pollutants in the storm drainage system. Rosboro does currently have testing data at the outfall on-site for heavy metals and currently, the levels are low enough that a Monitoring Waiver was granted by DEQ. No testing for mercury or bacteria is done regularly, but it is not considered a point source by either DEQ or the City. See Appendix 5 for Monitoring Waiver and Stormwater Testing Results for existing pollutants tested on-site. 7 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Analysis The run-off for the impervious areas has been calculated and the planter has been sized to meet or exceed the City of Springfield requirements. The calculations determine run-off using the Santa Barbara Urban Hydrograph (SBUH) Method and NRCS 24-Hour Type 1A Hyetograph as outlined Chapter 4 of the Engineering Design Standards and Procedures Manual. The facility capacity is based on the requirements and facility details found in City of Eugene Stormwater Design Manual. Note that only Basin 1B will be treated by vegetative treatment. The roof and industrial areas of the site will be treated through mechanical treatment due to site constraints. For analysis purposes, each basin required the following information as input data for the computer model: • Impervious Area (Ai), in acres • Curve Number (CNi), impervious • Travel Time (Tc) • Total Precipitation Precipitation data for the respective City of Springfield design storms are shown in Table 3 below. TABLE 3: 24-Hour Precipitation for Springfield, OR (City of Springfield Ordinance No. 6464) Storm Event Inches WQ 1.40 2-Year 3.12 5-Year 3.60 10-Year 4.46 25-Year 5.18 100-Year 6.48 TABLE 4: Catchment and Facility Table (See Exhibit 2, Appendix 1) Catchment Source Impervious Area Pervious Area Total Area (SF) Treatment Facility Color (SF) (Acres) (SF) (Acres) Basin 1A Building 149,400 3.43 0 0 149,400 Mechanical Basin 1B Parking 6,700 0.15 0 0 33,621 Planter 1B Basin 1C Paving & gravel 216,950 4.98 0 0 216,950 Mechanical Basin 2A Building 72,048 1.65 0 0 72,048 Mechanical Basin 2B Paving 87,608 2.01 0 0 87,608 Mechanical To size the planter, the following information was needed: • Bottom area, in square feet • Bottom perimeter length or bottom width, in feet • Storage depth, in inches All the water quality facilities meet the City of Springfield water quality requirements. For full calculations and results, see Appendix 3. 8 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Engineering Conclusions Based on the Engineering Design Standards and Procedures Manual requirements, the proposed facilities and conveyance components have enough capacity to handle the required storm events and should be approved as designed. 2300348-kg Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendix 1 Basin Maps [F P ] [F P ]DERAILFOFOFOFOEEOHUOHUOHUOHUOHUOHUOHU OHU OHUOHU OHUOHU OVERHEAD DUCTS OVERHEAD DUCTOVERHEAD DUCT24''SD18''SD48''SS48''SS48''SS48''SS24''SD24''SD24''SD1 2 ' ' S D TRENCH DRAIN 12''SD [FP]16''W [W][W][W][W] [FP][FP][FP][FP][FP][FP] [FP][FP][ FP ][FP][FP][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD]BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBRDRDRDRDRDRDRDRDRDRDRDRDRDRDRDRDRDRDMW #1MW #2TRANTRANEEEECECECECUSSSCOCOWWVLTWWHBFPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVCITY FHRDRDMWCOTELVLTUBSDDDDDDDDBASIN 2TOTAL IMPERVIOUS AREA:159,656 SF = 3.67 ACRESBASIN 1TOTAL IMPERVIOUS AREA:208,504 SF = 4.79 ACRESEXH-1SHEET LEGENDPROPERTY LINESTORMWATERBASINBOUNDARY [F P ] [F P ]DERAILFOFOFOFOEOHUOHUOHUOHUOHUOHUOHU OHU OHUOHU OHUOHU OVERHEAD DUCTS OVERHEAD DUCTOVERHEAD DUCT24''SD48''SS48''SS48''SS48''SS1 2 ' ' S D [FP]16''W [W][W][W][W] [FP][FP][FP][FP][FP][FP] [FP][FP][ FP ][FP][FP][SD][SD][SD][SD][SD][SD][SD]BBBBBBBBBBBBBBBBBRDRDRDRDRDTRANTRANEEEECECECECSSSCOCOWWVLTWWFPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVCITY FHRDCOTELVLTUBSDDDDDDSTORM TREATMENT STRUCTUREFOR BOTH BASIN 1 & 2BASIN 1B - PARKING LOTTOTAL IMPERVIOUS AREA:6,700 SF = 0.15 ACRESBASIN 1A - GLULAM BUILDINGTOTAL IMPERVIOUS AREA:149,400 SF = 3.43 ACRESBASIN 1C - PAVINGTOTAL IMPERVIOUS AREA:216,950 SF = 4.98 ACRESBASIN 2A - PLANER MILLTOTAL IMPERVIOUS AREA:72,048 SF = 1.65 ACRESBASIN 2B - PAVINGTOTAL IMPERVIOUS AREA:87,608 SF = 2.01 ACRESPLANTER 1BTREATMENT AREA = 222 SFEXH-2SHEET LEGENDPROPERTY LINESTORM PIPESTORMWATERBASINBOUNDARY Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendix 2 Stormwater Plan B1FAC1GEC2DTSPSPSPSPTTTTGIJHThe following non-stormwater discharges may occur at the facility:·Discharges from emergency or unplanned fire-fighting activities;·Fire hydrant flushing and maintenance;·Potable water, including water line flushing;·Uncontaminated condensate from air conditioners, coolers, chillers, and from other compressors;·Landscape watering and irrigation drainage;·Exterior vehicle wash water that does not use hot water or detergent; restricted to less than 8/wk;·Pavement wash water that does not use hot water, detergent or other cleaning products, no spills or leaks of toxic orhazardous materials having occurred (unless spilled material has been removed), and surfaces are swept beforewashing;·Routine external building wash down that does not use hot water, detergents or other cleaning products;·Uncontaminated ground water or spring water;·Foundation or footing drains where flows are not contaminated with process materials.B2 NOTEDESCRIPTIONDETAIL REF.1CONNECT TO EXISTING STORM STRUCTURE.FIELD VERIFY INVERT ELEVATIONS ANDLOCATION PRIOR TO CONSTRUCTION.2CONNECT TO EXISTING STORM PIPE.CONTRACTOR TO POTHOLE AND FIELDVERIFY SIZE, INVERT ELEVATIONS ANDLOCATION PRIOR TO CONSTRUCTION.ADGIBSON STEEL AREA DRAIN WITHFLO-GUARD FILTERSCBGIBSON STEEL CATCH BASIN WITHFLO-GUARD FILTERSOVOVERFLOW INLETFTPFLOW THROUGH PLANTERWQWATER QUALITY TREATMENT STRUCTURE.STRUCTURE TYPEPIPE LABELXXLF - XX" XXUTILITY SIZEUTILITY LENGTHUTILITY TYPES=X.XX%XX XX-XXN=XXXX.XXE=XXXX.XXRIM=IE IN = XX.XIE OUT = XX.XSTRUCTURE TYPE CALLOUTUTILITY TYPE (SD=STORM DRAINAGE, S=SANITARYSEWER, W=WATER, FP=FIRE PROTECTION)ID NUMBER (WHERE APPLICABLE)STRUCTURE INFO (WHERE APPLICABLE)LOCATION (WHERE APPLICABLE)STRUCTURE LABELSLOPE (WHERE APPLICABLE)CALLOUTDESCRIPTIONDETAIL REF.ADAREA DRAINCBCATCH BASINCOCLEANOUT TO GRADEFDFOUNDATION DRAINAGEMHMANHOLEOVOVERFLOW INLETPLUGPLUGSTUBSTUBTEETEE CONNECTIONWMWATER METERWQMHWATER QUALITY MANHOLEXUTILITY KEY NOTESUTILITY LABEL LEGEND[F P ] [F P ] [F P ] [F P ]DERAILFOFOFOFOFOFOFOFOE EETEOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHU OHUOHU OHU OHU OHU OHUOHUOHUOHU OHU OHU OHU OHUOHUOHUOHU EEEEOHU OHU OVERHEAD DUCTS OVERHEAD DUCTOVERHEAD DUCT24''SD24''SD24''SD48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS1 2 ' ' S D 1 2 ' ' S D 1 2 ' ' S D 12''SD 10''SD10''SD 8''SS8''SS[FP][FP][FP]16''W 16''W 16''W [W][W][W][W][W][W][W][W][W][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP] [ F P ] [FP] [FP] [FP] [FP][FP][FP][FP][ FP ] [ FP ][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP] [FP] [FP] [FP][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD]BBBBBBBBBBBBBBBBBBBBBBBBBRDRDRDRDRDTRANTRANEEEECECECECSSSSCOCOCOWWVLTWWFPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVCITY FH[FP][ F P ] [ F P ]RDNO TRUCKS NO PARKINGNO PARKINGAC UNITAC UNITCOCOCOCOCOCOCORDRDRDRDRDCOTELVLTTELVLTUBICV12"2-8"6''SD 10''SD6''SDSDDDDDDSDSDSDSDSDSD PLANER BUILDINGGLULAM BUILDINGEXISTING LUMBERSTORAGE WAREHOUSEPROJECT:220x1REVISIONS:CHECKED:wilson-architecture.com | 541-912-0878Springfield Plant ImprovementsRosboroSITE REVIEWDATE: 04.01.24800 Willamette Street, Suite 400Eugene, OR 97401O:541.684.4902F:541.684.4909www.kpff.comC400OVERALL STORM DRAINAGEPLANSCALE501 INCH = 50 FEET501000C401C402 NOTEDESCRIPTIONDETAIL REF.1CONNECT TO EXISTING STORM STRUCTURE.FIELD VERIFY INVERT ELEVATIONS ANDLOCATION PRIOR TO CONSTRUCTION.2CONNECT TO EXISTING STORM PIPE.CONTRACTOR TO POTHOLE AND FIELDVERIFY SIZE, INVERT ELEVATIONS ANDLOCATION PRIOR TO CONSTRUCTION.ADGIBSON STEEL AREA DRAIN WITHFLO-GUARD FILTERSCBGIBSON STEEL CATCH BASIN WITHFLO-GUARD FILTERSOVOVERFLOW INLETFTPFLOW THROUGH PLANTERWQWATER QUALITY TREATMENT STRUCTURE.STRUCTURE TYPEPIPE LABELXXLF - XX" XXUTILITY SIZEUTILITY LENGTHUTILITY TYPES=X.XX%XX XX-XXN=XXXX.XXE=XXXX.XXRIM=IE IN = XX.XIE OUT = XX.XSTRUCTURE TYPE CALLOUTUTILITY TYPE (SD=STORM DRAINAGE, S=SANITARYSEWER, W=WATER, FP=FIRE PROTECTION)ID NUMBER (WHERE APPLICABLE)STRUCTURE INFO (WHERE APPLICABLE)LOCATION (WHERE APPLICABLE)STRUCTURE LABELSLOPE (WHERE APPLICABLE)CALLOUTDESCRIPTIONDETAIL REF.ADAREA DRAINCBCATCH BASINCOCLEANOUT TO GRADEFDFOUNDATION DRAINAGEMHMANHOLEOVOVERFLOW INLETPLUGPLUGSTUBSTUBTEETEE CONNECTIONWMWATER METERWQMHWATER QUALITY MANHOLEXUTILITY KEY NOTESUTILITY LABEL LEGEND[F P ] [F P ] [F P ] [F P ] [F P ] [F P ]DERAILFOFOFOFOFOFOFOFOFOFOFOFOFOOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHU24''SD24''SD24''SD24''SD24''SD48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS48''SS[FP][FP] [FP][SD][SD][SD][SD][SD][SD]RDSSFPIVPIVPIV24''SDAC UNITAC UNITRDRD8''SD6''SD 6''SD8''SD 10''SD10''SD10''SD10''SD6''SD6''SDSDDDDSDSDSDSD SDSDSDSD SD SD SD SD MH-2RIM=472.97IE 24" IN=467.28 (S)IE 8" IN=467.93 (N)IE 24" OUT=467.28 (W)IE 24"=464.74IE 24"=464.74SD WQ-1RIM = 472.26WQSD MH-3RIM=473.05IE 24" IN=465.93 (E)IE 24" OUT=465.93 (W)IE 24"=467.67IE 18"=467.67IE 18"=467.67SD MH-1RIM = 472.752CONNECT TO EXISTING STORM STRUCTURESD EX. MH-3RIM=475.44IE 24" IN=464.57 (E) 24"IE 12" IN=466.92 (N) EX. 12"IE 24" IN=464.73 (S) EX. 24"IE 48" OUT=464.57 (SW) EX.FIELD VERIFY POINTOF CONNECTION102 LF - 24"SDS=0.38%382 LF - 24"SDS=0.35%56 LF - 24"SDS=0.30%344 LF - 24"SDS=0.33%228 LF - 8"SDS=1.00%292 LF - 12"SDS=1.00%141 LF - 18"SDS=0.50%189 L F - 1 8 " S D S=0.5 0 %ADCBADCBCBCBCBADCBCBCBCBGLULAM BUILDING46 LF - 6"SD S=2.00%27 LF - 8"SDS=1.00%CBCBEEEIE 24"=464.80IE 24"=464.80IE 12"=465.23SD MH-4RIM = 467.73MHCONNECT TO EXISTING STORM STRUCTURESD EX. MH-2RIM=471.72IE 24" IN=466.23 (W) EX.IE 6" IN=467.19 (SW) EX.IE 8" IN=467.19 (N)IE 8" IN=467.19 (E)IE 24" OUT=465.72 (S) EX.FIELD VERIFY POINTOF CONNECTIONAPPROXIMATE LOCATION OFNON-SURVEYED STORM DRAINAGE LINE.CONNECT EXISTING STORMSYSTEM TO PROPOSED STORM.OVFTPPROJECT:220x1REVISIONS:CHECKED:wilson-architecture.com | 541-912-0878Springfield Plant ImprovementsRosboroSITE REVIEWDATE: 04.01.24800 Willamette Street, Suite 400Eugene, OR 97401O:541.684.4902F:541.684.4909www.kpff.comC401SCALE301 INCH = 30 FEET30600GLULAM BUILDINGGLULAM STORM DRAINAGEPLANFO R I N FO RM A T IO NON L Y NOTEDESCRIPTIONDETAIL REF.1CONNECT TO EXISTING STORM STRUCTURE.FIELD VERIFY INVERT ELEVATIONS ANDLOCATION PRIOR TO CONSTRUCTION.2CONNECT TO EXISTING STORM PIPE.CONTRACTOR TO POTHOLE AND FIELDVERIFY SIZE, INVERT ELEVATIONS ANDLOCATION PRIOR TO CONSTRUCTION.ADGIBSON STEEL AREA DRAIN WITHFLO-GUARD FILTERSCBGIBSON STEEL CATCH BASIN WITHFLO-GUARD FILTERSOVOVERFLOW INLETFTPFLOW THROUGH PLANTERWQWATER QUALITY TREATMENT STRUCTURE.STRUCTURE TYPEPIPE LABELXXLF - XX" XXUTILITY SIZEUTILITY LENGTHUTILITY TYPES=X.XX%XX XX-XXN=XXXX.XXE=XXXX.XXRIM=IE IN = XX.XIE OUT = XX.XSTRUCTURE TYPE CALLOUTUTILITY TYPE (SD=STORM DRAINAGE, S=SANITARYSEWER, W=WATER, FP=FIRE PROTECTION)ID NUMBER (WHERE APPLICABLE)STRUCTURE INFO (WHERE APPLICABLE)LOCATION (WHERE APPLICABLE)STRUCTURE LABELSLOPE (WHERE APPLICABLE)CALLOUTDESCRIPTIONDETAIL REF.ADAREA DRAINCBCATCH BASINCOCLEANOUT TO GRADEFDFOUNDATION DRAINAGEMHMANHOLEOVOVERFLOW INLETPLUGPLUGSTUBSTUBTEETEE CONNECTIONWMWATER METERWQMHWATER QUALITY MANHOLEXUTILITY KEY NOTESUTILITY LABEL LEGENDEEEEEEEEEEETTTTEE OHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHUOHU OHU OHU OHU OHU OHU OHU OHU OHU OHU OHU OHUOHUOHUOHUOHUOHUOHUOHUOHU OHUOHUEEEEEEEEEEEOHU OHU OHU OVERHEAD DUCTS OVERHEAD DUCTOVERHEAD DUCT10''SD8''SD12''SD12''SD12''SD12''SD12''SD12''SD12''SD12''SD6''SD18''SD6''SD6''SD12''SD 12''SD 12''SD 12''SD12''SD12''SD10''SD10''SD10''SD10''SD10''SD 10''SD 8''SD8''SD8''SD 8''SD 6''SD 8''SS8''SS8''SS8''SS[FP][FP][FP][FP]16''W 16''W 16''W 16''W 16''W 16''W 16''W 16''W 16''W [W][W][W][W][W][W][W][W][W][W][W][W][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP] [FP] [FP] [FP] [FP][FP][FP]WWW[FP][FP][FP][FP][FP][FP][FP] [ FP ] [ FP ] [ FP ] [ FP ] [ FP ] [ FP ][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP][FP] [FP] [FP] [ F P ] [ F P ][FP][FP] [FP] [FP] [FP] [FP] [FP] [FP] [FP][FP][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD][SD]BBBBBBBBBBBBBBRDRDRDRDTRANEEECECECECSSCOCOCOWWVLTWWPIVPIVPIVPIVPIVPIVPIVPIVPIVPIVCITY FH[FP][FP] [ F P ] [ F P ][FP][FP][ F P ] [ F P ] [ F P ] [ F P ] [ F P ]RDDD180 LF - 12 "SDS=0.50%221 LF - 6"SDS=0.50%100 LF - 12"SDS=0.38%71 LF - 12"SD S=0.50%CBCBCBCBCBCONNECT TO EXISTING STORM STRUCTURESD EX-44RIM=473.01IE 12" IN=471.86 (SE)IE 10" IN=-1.85 (N) EX.IE 10" OUT=471.73 (NW) EX.FIELD VERIFY POINTOF CONNECTION125 LF - 12"SDS=0.36%CBCBCBCBPLANER BUILDINGCBCBCB117 LF - 12"SDS=0.38%15 LF - 12"SDS=0.41%32 LF - 6"SDS=0.75%51 LF - 12"SD S=0.50%55 LF - 12"SD S=0.50%82 LF - 8"SDS=1.00%CONNECT TO EXISTING STORM STRUCTURESD EX. AD-1RIM=473.54IE 12" IN=471.91 (NE)IE OUT=471.89 (SW) EX. 12"FIELD VERIFY POINTOF CONNECTIONEECONNECT TO EXISTING STORM PIPESD CONN-1IE 8" IN=470.86 (E)FIELD VERIFY POINTOF CONNECTION92 LF - 8"SDS=1.00%CONNECT TO EXISTING STORM PIPESD CONN-2IE 8" IN=471.68 (E)FIELD VERIFY POINTOF CONNECTIONPROJECT:220x1REVISIONS:CHECKED:wilson-architecture.com | 541-912-0878Springfield Plant ImprovementsRosboroSITE REVIEWDATE: 04.01.24800 Willamette Street, Suite 400Eugene, OR 97401O:541.684.4902F:541.684.4909www.kpff.comC402SCALE201 INCH = 20 FEET20400PLANER MILLPLANER BUILDING STORMDRAINAGE PLAN Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendix 3 Analysis Calculations SBUH Calculation Worksheet for City of Springfield Storm Events Project Name: Rosboro Springfield Plant Improvements Date: 03/20/24 Designer: RR/MR Basin: Ex. 1 User-Supplied Data Pervious Area Impervious Area Pervious Area, SF 184,657 208,504 Pervious Area, Acres 4.24 4.79 Pervious Area Curve Number, CNperv 80 98 Time of Concentration, Tc, minutes5 Note: minimum Tc is five minutes City of Springfield 24-Hour Rainfall Depths (NRCS Type 1A distribution) Recurrence Interval WQ25 10 25 50 100 Inches 1.4 3.12 3.6 4.46 5.18 6.48 Calculated Data Total Project Area, Acres 9.03 Total Project Area, Square Feet 393,161 Recurrence Interval WQ25 10 25 50 100 Peak Flow Rate, Qpeak, cfs 1.66 5.21 6.29 8.30 10.02 0.00 13.17 Total Runoff Volume, V, cubic feet 24,199 70,807 84,895 110,750 132,8250 173,338 Time to Peak Runoff, hours 7.83 7.83 7.83 7.83 7.83 0.00 7.83 Runoff Hydrograph Impervious Area, SF Impervious Area, Acres Impervious Area Curve Number, CNimp0.002.004.006.008.0010.0012.0014.000 500 1000 1500 2000 2500Runoff, cfsTime, minutesWQ2-Year5-Year10-Year25-Year50-Year100-Year SBUH Calculation Worksheet for City of Springfield Storm Events Project Name: Rosboro Springfield Plant Improvements Date: 03/20/2024 Designer: RR/MR Basin: Ex. 2 User-Supplied Data Pervious Area Impervious Area Pervious Area, SF0 159,656 Pervious Area, Acres 0.00 3.67 Pervious Area Curve Number, CNperv 80 98 Time of Concentration, Tc, minutes5 Note: minimum Tc is five minutes City of Springfield 24-Hour Rainfall Depths (NRCS Type 1A distribution) Recurrence Interval WQ25 10 25 50 100 Inches 1.4 3.12 3.6 4.46 5.18 6.48 Calculated Data Total Project Area, Acres 3.67 Total Project Area, Square Feet 159,656 Recurrence Interval WQ25 10 25 50 100 Peak Flow Rate, Qpeak, cfs 1.24 2.97 3.45 4.30 5.01 0.00 6.28 Total Runoff Volume, V, cubic feet 15,723 38,421 44,786 56,200 65,7640 83,039 Time to Peak Runoff, hours 7.83 7.83 7.83 7.83 7.83 0.00 7.83 Runoff Hydrograph Impervious Area, SF Impervious Area, Acres Impervious Area Curve Number, CNimp0.001.002.003.004.005.006.007.000 500 1000 1500 2000 2500Runoff, cfsTime, minutesWQ2-Year5-Year10-Year25-Year50-Year100-Year SBUH Calculation Worksheet for City of Springfield Storm Events Project Name: Rosboro Sprinfield Plant Improvements Date: 03/20/2024 Designer: RR/MR Basin: 1A User-Supplied Data Pervious Area Impervious Area Pervious Area, SF0 149,400 Pervious Area, Acres 0.00 3.43 Pervious Area Curve Number, CNperv 80 98 Time of Concentration, Tc, minutes5 Note: minimum Tc is five minutes City of Springfield 24-Hour Rainfall Depths (NRCS Type 1A distribution) Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Inches 1.4 3.12 3.6 4.46 5.18 6.48 Calculated Data Total Project Area, Acres 3.43 Total Project Area, Square Feet 149,400 Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Peak Flow Rate, Qpeak, cfs 1.16 2.78 3.23 4.02 4.68 0.00 5.88 Total Runoff Volume, V, cubic feet 14,713 35,953 41,909 52,590 61,5390 77,705 Time to Peak Runoff, hours 7.83 7.83 7.83 7.83 7.83 0.00 7.83 Runoff Hydrograph Impervious Area, SF Impervious Area, Acres Impervious Area Curve Number, CNimp0.001.002.003.004.005.006.007.000 500 1000 1500 2000 2500Runoff, cfsTime, minutesWQ2-Year5-Year10-Year25-Year50-Year100-Year 800 Willamette Street, Suite 400 Eugene, OR 97401 541.684.4902 kpff.com SBUH Calculation Worksheet for City of Springfield Storm Events Project Name: Rosboro Springfield Plant Improvements Date: 03/20/2024 Designer: RR/MR Basin: 1B User-Supplied Data Pervious Area Impervious Area Pervious Area, SF0 6,700 Pervious Area, Acres 0.00 0.15 Pervious Area Curve Number, CNperv 80 98 Time of Concentration, Tc, minutes5 Note: minimum Tc is five minutes City of Springfield 24-Hour Rainfall Depths (NRCS Type 1A distribution) Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Inches 1.4 3.12 3.6 4.46 5.18 6.48 Calculated Data Total Project Area, Acres 0.15 Total Project Area, Square Feet 6,700 Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Peak Flow Rate, Qpeak, cfs 0.05 0.12 0.14 0.18 0.21 0.00 0.26 Total Runoff Volume, V, cubic feet 660 1,612 1,879 2,358 2,7600 3,485 Time to Peak Runoff, hours 7.83 7.83 7.83 7.83 7.83 0.00 7.83 Runoff Hydrograph Impervious Area, SF Impervious Area, Acres Impervious Area Curve Number, CNimp0.000.050.100.150.200.250.300 500 1000 1500 2000 2500Runoff, cfsTime, minutesWQ2-Year5-Year10-Year25-Year50-Year100-Year 800 Willamette Street, Suite 400 Eugene, OR 97401 541.684.4902 kpff.com Springfield Stormwater Facility CalculatorProject Name: Rosboro Springfield Plant Improvements Basin: 1B Instructions:Date: 03/20/2024 1. Choose Facility Type 2. Choose shape 3. Complete information in highlighted cells Facility Planter Grassy Shape Rectangular Below-Grade Bottom Area:222 sf 108 Bottom Width:6 ft 24 Vertical Sides 4 0.40 Storage Depth:6 in Growing Media:18 in 1.00 2.00 Surface Storage Capacity 111 cf Infiltration Area 222 sf GM Infiltration Rate 2.5 in/hr Infiltration Capacity (avg)0.013 cfs Results SURFACE CAPACITY Recurrance Interval Peak Flow (cfs) Volume (cf) Meets Infiltration? WQ 0.0128 577 Filtration Only 2-Yr 0.1247 1,506 5-Yr 0.1447 1,776 10-Yr 0.1803 2,251 25-Yr 0.2101 2,653 50-Yr 0.0000 0 100-Yr 0.2637 3,376 N/A 75% N/A N/A Rock Capacity N/A N/A N/A N/A Impermeable Liner WATER QUALITY EVENT PASS ROCK CAPACITY N/A Project Name: Rosboro Springfield Plant Improvements Basin: 1B Date: 03/20/2024Water Quality Event Surface Facility Modeling Water Quality Event Below Grade Modeling 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%0.0000 0.0100 0.0200 0.0300 0.0400 0.0500 0.0600 0 500 1000 1500 2000 2500Runoff, cfsTime, minutes Surface Inflow Infiltration Capacity Percolation to Subsurface Overflow Surface Capacity 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%0.0000 0.0020 0.0040 0.0060 0.0080 0.0100 0.0120 0.0140 0 500 1000 1500 2000 2500Runoff, cfsTime, minutes Rock Inflow Infiltration Capacity Overflow Rock Capacity 800 Willamette Street, Suite 400 Eugene, OR 97401 541.684.4902 kpff.com SBUH Calculation Worksheet for City of Springfield Storm Events Project Name: Rosboro Springfield Plant Improvements Date: 03/20/2024 Designer: RR/MR Basin: 1C User-Supplied Data Pervious Area Impervious Area Pervious Area, SF 20,111 216,950 Pervious Area, Acres 0.46 4.98 Pervious Area Curve Number, CNperv 80 98 Time of Concentration, Tc, minutes5 Note: minimum Tc is five minutes City of Springfield 24-Hour Rainfall Depths (NRCS Type 1A distribution) Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Inches 1.4 3.12 3.6 4.46 5.18 6.48 Calculated Data Total Project Area, Acres 5.44 Total Project Area, Square Feet 237,061 Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Peak Flow Rate, Qpeak, cfs 1.70 4.18 4.88 6.13 7.18 0.00 9.08 Total Runoff Volume, V, cubic feet 21,764 54,456 63,734 80,437 94,4760 119,906 Time to Peak Runoff, hours 7.83 7.83 7.83 7.83 7.83 0.00 7.83 Runoff Hydrograph Impervious Area, SF Impervious Area, Acres Impervious Area Curve Number, CNimp0.001.002.003.004.005.006.007.008.009.0010.000 500 1000 1500 2000 2500Runoff, cfsTime, minutesWQ2-Year5-Year10-Year25-Year50-Year100-Year 800 Willamette Street, Suite 400 Eugene, OR 97401 541.684.4902 kpff.com SBUH Calculation Worksheet for City of Springfield Storm Events Project Name: Rosboro Springfield Plant Improvements Date: 03/20/2024 Designer: RR/MR Basin: 2A User-Supplied Data Pervious Area Impervious Area Pervious Area, SF0 72,048 Pervious Area, Acres 0.00 1.65 Pervious Area Curve Number, CNperv 80 98 Time of Concentration, Tc, minutes5 Note: minimum Tc is five minutes City of Springfield 24-Hour Rainfall Depths (NRCS Type 1A distribution) Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Inches 1.4 3.12 3.6 4.46 5.18 6.48 Calculated Data Total Project Area, Acres 1.65 Total Project Area, Square Feet 72,048 Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Peak Flow Rate, Qpeak, cfs 0.56 1.34 1.56 1.94 2.26 0.00 2.84 Total Runoff Volume, V, cubic feet 7,095 17,338 20,210 25,362 29,6770 37,473 Time to Peak Runoff, hours 7.83 7.83 7.83 7.83 7.83 0.00 7.83 Runoff Hydrograph Impervious Area, SF Impervious Area, Acres Impervious Area Curve Number, CNimp0.000.501.001.502.002.503.000 500 1000 1500 2000 2500Runoff, cfsTime, minutesWQ2-Year5-Year10-Year25-Year50-Year100-Year 800 Willamette Street, Suite 400 Eugene, OR 97401 541.684.4902 kpff.com SBUH Calculation Worksheet for City of Springfield Storm Events Project Name: Rosboro Springfield Plant Improvements Date: 03/20/2024 Designer: RR/MR Basin: 2B User-Supplied Data Pervious Area Impervious Area Pervious Area, SF0 87,608 Pervious Area, Acres 0.00 2.01 Pervious Area Curve Number, CNperv 80 98 Time of Concentration, Tc, minutes5 Note: minimum Tc is five minutes City of Springfield 24-Hour Rainfall Depths (NRCS Type 1A distribution) Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Inches 1.4 3.12 3.6 4.46 5.18 6.48 Calculated Data Total Project Area, Acres 2.01 Total Project Area, Square Feet 87,608 Recurrence Interval WQ 2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr Peak Flow Rate, Qpeak, cfs 0.68 1.63 1.89 2.36 2.75 0.00 3.45 Total Runoff Volume, V, cubic feet 8,628 21,083 24,575 30,839 36,0860 45,566 Time to Peak Runoff, hours 7.83 7.83 7.83 7.83 7.83 0.00 7.83 Runoff Hydrograph Impervious Area, SF Impervious Area, Acres Impervious Area Curve Number, CNimp0.000.501.001.502.002.503.003.504.000 500 1000 1500 2000 2500Runoff, cfsTime, minutesWQ2-Year5-Year10-Year25-Year50-Year100-Year 800 Willamette Street, Suite 400 Eugene, OR 97401 541.684.4902 kpff.com Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendix 4 Contech CDS Hydrodynamic Separator Documentation CDS Guide Operation, Design, Performance and Maintenance ENGINEERED SOLUTIONS 2 CDS® Using patented continuous deflective separation technology, the CDS system screens, separates and traps debris, sediment, and oil and grease from stormwater runoff. The indirect screening capability of the system allows for 100% removal of floatables and neutrally buoyant material without blinding. Flow and screening controls physically separate captured solids, and minimize the re-suspension and release of previously trapped pollutants. Inline units can treat up to 6 cfs, and internally bypass flows in excess of 50 cfs (1416 L/s). Available precast or cast-in- place, offline units can treat flows from 1 to 300 cfs (28.3 to 8495 L/s). The pollutant removal capacity of the CDS system has been proven in lab and field testing. Operation Overview Stormwater enters the diversion chamber where the diversion weir guides the flow into the unit’s separation chamber and pollutants are removed from the flow. All flows up to the system’s treatment design capacity enter the separation chamber and are treated. Swirl concentration and screen deflection force floatables and solids to the center of the separation chamber where 100% of floatables and neutrally buoyant debris larger than the screen apertures are trapped. Stormwater then moves through the separation screen, under the oil baffle and exits the system. The separation screen remains clog free due to continuous deflection. During the flow events exceeding the treatment design capacity, the diversion weir bypasses excessive flows around the separation chamber, so captured pollutants are retained in the separation cylinder. Design Basics There are three primary methods of sizing a CDS system. The Water Quality Flow Rate Method determines which model size provides the desired removal efficiency at a given flow rate for a defined particle size. The Rational Rainfall Method™ or the and Probabilistic Method is used when a specific removal efficiency of the net annual sediment load is required. Typically in the Unites States, CDS systems are designed to achieve an 80% annual solids load reduction based on lab generated performance curves for a gradation with an average particle size (d50) of 125 microns (μm). For some regulatory environments, CDS systems can also be designed to achieve an 80% annual solids load reduction based on an average particle size (d50) of 75 microns (μm) or 50 microns (μm). Water Quality Flow Rate Method In some cases, regulations require that a specific treatment rate, often referred to as the water quality design flow (WQQ), be treated. This WQQ represents the peak flow rate from either an event with a specific recurrence interval, e.g. the six-month storm, or a water quality depth, e.g. 1/2-inch (13 mm) of rainfall. The CDS is designed to treat all flows up to the WQQ. At influent rates higher than the WQQ, the diversion weir will direct most flow exceeding the WQQ around the separation chamber. This allows removal efficiency to remain relatively constant in the separation chamber and eliminates the risk of washout during bypass flows regardless of influent flow rates. Treatment flow rates are defined as the rate at which the CDS will remove a specific gradation of sediment at a specific removal efficiency. Therefore the treatment flow rate is variable, based on the gradation and removal efficiency specified by the design engineer. Rational Rainfall Method™ Differences in local climate, topography and scale make every site hydraulically unique. It is important to take these factors into consideration when estimating the long-term performance of any stormwater treatment system. The Rational Rainfall Method combines site-specific information with laboratory generated performance data, and local historical precipitation records to estimate removal efficiencies as accurately as possible. Short duration rain gauge records from across the United States and Canada were analyzed to determine the percent of the total annual rainfall that fell at a range of intensities. US stations’ depths were totaled every 15 minutes, or hourly, and recorded in 0.01-inch increments. Depths were recorded hourly with 1-mm resolution at Canadian stations. One trend was consistent at all sites; the vast majority of precipitation fell at low intensities and high intensity storms contributed relatively little to the total annual depth. These intensities, along with the total drainage area and runoff coefficient for each specific site, are translated into flow rates using the Rational Rainfall Method. Since most sites are relatively small and highly impervious, the Rational Rainfall Method is appropriate. Based on the runoff flow rates calculated for each intensity, operating rates within a proposed CDS system are GRATE INLET (CAST IRON HOOD FOR CURB INLET OPENING) CREST OF BYPASS WEIR (ONE EACH SIDE) INLET (MULTIPLE PIPES POSSIBLE) OIL BAFFLE SUMP STORAGESEPARATION SLAB TREATMENT SCREEN OUTLET INLET FLUME SEPARATION CYLINDER CLEAN OUT (REQUIRED) DEFLECTION PAN, 3 SIDED (GRATE INLET DESIGN) 3 determined. Performance efficiency curve determined from full scale laboratory tests on defined sediment PSDs is applied to calculate solids removal efficiency. The relative removal efficiency at each operating rate is added to produce a net annual pollutant removal efficiency estimate. Probabilistic Rational Method The Probabilistic Rational Method is a sizing program Contech developed to estimate a net annual sediment load reduction for a particular CDS model based on site size, site runoff coefficient, regional rainfall intensity distribution, and anticipated pollutant characteristics. The Probabilistic Method is an extension of the Rational Method used to estimate peak discharge rates generated by storm events of varying statistical return frequencies (e.g. 2-year storm event). Under the Rational Method, an adjustment factor is used to adjust the runoff coefficient estimated for the 10-year event, correlating a known hydrologic parameter with the target storm event. The rainfall intensities vary depending on the return frequency of the storm event under consideration. In general, these two frequency dependent parameters (rainfall intensity and runoff coefficient) increase as the return frequency increases while the drainage area remains constant. These intensities, along with the total drainage area and runoff coefficient for each specific site, are translated into flow rates using the Rational Method. Since most sites are relatively small and highly impervious, the Rational Method is appropriate. Based on the runoff flow rates calculated for each intensity, operating rates within a proposed CDS are determined. Performance efficiency curve on defined sediment PSDs is applied to calculate solids removal efficiency. The relative removal efficiency at each operating rate is added to produce a net annual pollutant removal efficiency estimate. Treatment Flow Rate The inlet throat area is sized to ensure that the WQQ passes through the separation chamber at a water surface elevation equal to the crest of the diversion weir. The diversion weir bypasses excessive flows around the separation chamber, thus preventing re-suspension or re-entrainment of previously captured particles. Hydraulic Capacity The hydraulic capacity of a CDS system is determined by the length and height of the diversion weir and by the maximum allowable head in the system. Typical configurations allow hydraulic capacities of up to ten times the treatment flow rate. The crest of the diversion weir may be lowered and the inlet throat may be widened to increase the capacity of the system at a given water surface elevation. The unit is designed to meet project specific hydraulic requirements. Performance Full-Scale Laboratory Test Results A full-scale CDS system (Model CDS2020-5B) was tested at the facility of University of Florida, Gainesville, FL. This CDS unit was evaluated under controlled laboratory conditions of influent flow rate and addition of sediment. Two different gradations of silica sand material (UF Sediment & OK-110) were used in the CDS performance evaluation. The particle size distributions (PSDs) of the test materials were analyzed using standard method “Gradation ASTM D-422 “Standard Test Method for Particle-Size Analysis of Soils” by a certified laboratory. UF Sediment is a mixture of three different products produced by the U.S. Silica Company: “Sil-Co-Sil 106”, “#1 DRY” and “20/40 Oil Frac”. Particle size distribution analysis shows that the UF Sediment has a very fine gradation (d50 = 20 to 30 μm) covering a wide size range (Coefficient of Uniformity, C averaged at 10.6). In comparison with the hypothetical TSS gradation specified in the NJDEP (New Jersey Department of Environmental Protection) and NJCAT (New Jersey Corporation for Advanced Technology) protocol for lab testing, the UF Sediment covers a similar range of particle size but with a finer d50 (d50 for NJDEP is approximately 50 μm) (NJDEP, 2003). The OK-110 silica sand is a commercial product of U.S. Silica Sand. The particle size distribution analysis of this material, also included in Figure 1, shows that 99.9% of the OK-110 sand is finer than 250 microns, with a mean particle size (d50) of 106 microns. The PSDs for the test material are shown in Figure 1. Figure 1. Particle size distributions Tests were conducted to quantify the performance of a specific CDS unit (1.1 cfs (31.3-L/s) design capacity) at various flow rates, ranging from 1% up to 125% of the treatment design capacity of the unit, using the 2400 micron screen. All tests were conducted with controlled influent concentrations of approximately 200 mg/L. Effluent samples were taken at equal time intervals across the entire duration of each test run. These samples were then processed with a Dekaport Cone sample splitter to obtain representative sub-samples for Suspended Sediment Concentration (SSC) testing using ASTM D3977-97 “Standard Test Methods for Determining Sediment Concentration in Water Samples”, and particle size distribution analysis. Results and Modeling Based on the data from the University of Florida, a performance model was developed for the CDS system. A regression analysis was used to develop a fitting curve representative of the scattered data points at various design flow rates. This model, which demonstrated good agreement with the laboratory data, can then be used to predict CDS system performance with respect 4 to SSC removal for any particle size gradation, assuming the particles are inorganic sandy-silt. Figure 2 shows CDS predictive performance for two typical particle size gradations (NJCAT gradation and OK-110 sand) as a function of operating rate. Figure 2. CDS stormwater treatment predictive performance for various particle gradations as a function of operating rate. Many regulatory jurisdictions set a performance standard for hydrodynamic devices by stating that the devices shall be capable of achieving an 80% removal efficiency for particles having a mean particle size (d50) of 125 microns (e.g. Washington State Department of Ecology — WASDOE - 2008). The model can be used to calculate the expected performance of such a PSD (shown in Figure 3). The model indicates (Figure 4) that the CDS system with 2400 micron screen achieves approximately 80% removal at the design (100%) flow rate, for this particle size distribution (d50 = 125 μm). Figure 3. WASDOE PSD Figure 4. Modeled performance for WASDOE PSD. Maintenance The CDS system should be inspected at regular intervals and maintained when necessary to ensure optimum performance. The rate at which the system collects pollutants will depend more heavily on site activities than the size of the unit. For example, unstable soils or heavy winter sanding will cause the grit chamber to fill more quickly but regular sweeping of paved surfaces will slow accumulation. Inspection Inspection is the key to effective maintenance and is easily performed. Pollutant transport and deposition may vary from year to year and regular inspections will help ensure that the system is cleaned out at the appropriate time. At a minimum, inspections should be performed twice per year (e.g. spring and fall) however more frequent inspections may be necessary in climates where winter sanding operations may lead to rapid accumulations, or in equipment washdown areas. Installations should also be inspected more frequently where excessive amounts of trash are expected. The visual inspection should ascertain that the system components are in working order and that there are no blockages or obstructions in the inlet and separation screen. The inspection should also quantify the accumulation of hydrocarbons, trash, and sediment in the system. Measuring pollutant accumulation can be done with a calibrated dipstick, tape measure or other measuring instrument. If absorbent material is used for enhanced removal of hydrocarbons, the level of discoloration of the sorbent material should also be identified 5 during inspection. It is useful and often required as part of an operating permit to keep a record of each inspection. A simple form for doing so is provided. Access to the CDS unit is typically achieved through two manhole access covers. One opening allows for inspection and cleanout of the separation chamber (cylinder and screen) and isolated sump. The other allows for inspection and cleanout of sediment captured and retained outside the screen. For deep units, a single manhole access point would allows both sump cleanout and access outside the screen. The CDS system should be cleaned when the level of sediment has reached 75% of capacity in the isolated sump or when an appreciable level of hydrocarbons and trash has accumulated. If absorbent material is used, it should be replaced when significant discoloration has occurred. Performance will not be impacted until 100% of the sump capacity is exceeded however it is recommended that the system be cleaned prior to that for easier removal of sediment. The level of sediment is easily determined by measuring from finished grade down to the top of the sediment pile. To avoid underestimating the level of sediment in the chamber, the measuring device must be lowered to the top of the sediment pile carefully. Particles at the top of the pile typically offer less resistance to the end of the rod than consolidated particles toward the bottom of the pile. Once this measurement is recorded, it should be compared to the as-built drawing for the unit to determine weather the height of the sediment pile off the bottom of the sump floor exceeds 75% of the total height of isolated sump. Cleaning Cleaning of a CDS systems should be done during dry weather conditions when no flow is entering the system. The use of a vacuum truck is generally the most effective and convenient method of removing pollutants from the system. Simply remove the manhole covers and insert the vacuum hose into the sump. The system should be completely drained down and the sump fully evacuated of sediment. The area outside the screen should also be cleaned out if pollutant build-up exists in this area. In installations where the risk of petroleum spills is small, liquid contaminants may not accumulate as quickly as sediment. However, the system should be cleaned out immediately in the event of an oil or gasoline spill. Motor oil and other hydrocarbons that accumulate on a more routine basis should be removed when an appreciable layer has been captured. To remove these pollutants, it may be preferable to use absorbent pads since they are usually less expensive to dispose than the oil/water emulsion that may be created by vacuuming the oily layer. Trash and debris can be netted out to separate it from the other pollutants. The screen should be cleaned to ensure it is free of trash and debris. Manhole covers should be securely seated following cleaning activities to prevent leakage of runoff into the system from above and also to ensure that proper safety precautions have been followed. Confined space entry procedures need to be followed if physical access is required. Disposal of all material removed from the CDS system should be done in accordance with local regulations. In many jurisdictions, disposal of the sediments may be handled in the same manner as the disposal of sediments removed from catch basins or deep sump manholes. Check your local regulations for specific requirements on disposal. 6 Note: To avoid underestimating the volume of sediment in the chamber, carefully lower the measuring device to the top of the sediment pile. Finer silty particles at the top of the pile may be more difficult to feel with a measuring stick. These finer particles typically offer less resistance to the end of the rod than larger particles toward the bottom of the pile. CDS Model Diameter Distance from Water Surface to Top of Sediment Pile Sediment Storage Capacity ft m ft m y3 m3 CDS1515 3 0.9 3.0 0.9 0.5 0.4 CDS2015 4 1.2 3.0 0.9 0.9 0.7 CDS2015 5 1.5 3.0 0.9 1.3 1.0 CDS2020 5 1.5 3.5 1.1 1.3 1.0 CDS2025 5 1.5 4.0 1.2 1.3 1.0 CDS3020 6 1.8 4.0 1.2 2.1 1.6 CDS3025 6 1.8 4.0 1.2 2.1 1.6 CDS3030 6 1.8 4.6 1.4 2.1 1.6 CDS3035 6 1.8 5.0 1.5 2.1 1.6 CDS4030 8 2.4 4.6 1.4 5.6 4.3 CDS4040 8 2.4 5.7 1.7 5.6 4.3 CDS4045 8 2.4 6.2 1.9 5.6 4.3 CDS5640 10 3.0 6.3 1.9 8.7 6.7 CDS5653 10 3.0 7.7 2.3 8.7 6.7 CDS5668 10 3.0 9.3 2.8 8.7 6.7 CDS5678 10 3.0 10.3 3.1 8.7 6.7 Table 1: CDS Maintenance Indicators and Sediment Storage Capacities 7 CDS Inspection & Maintenance Log CDS Model: Location: Water Floatable Describe Maintenance Date depth to Layer Maintenance Personnel Comments sediment1 Thickness2 Performed —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— 1. The water depth to sediment is determined by taking two measurements with a stadia rod: one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than the values listed in table 1 the system should be cleaned out. Note: to avoid underestimating the volume of sediment in the chamber, the measuring device must be carefully lowered to the top of the sediment pile. 2. For optimum performance, the system should be cleaned out when the floating hydrocarbon layer accumulates to an appreciable thickness. In the event of an oil spill, the system should be cleaned immediately. SUPPORT • Drawings and specifications are available at www.ContechES.com. • Site-specific design support is available from our engineers. ©2017 Contech Engineered Solutions LLC, a QUIKRETE Company Contech Engineered Solutions provides site solutions for the civil engineering industry. Contech’s portfolio includes bridges, drainage, sanitary sewer, earth stabilization and stormwater treatment products. For information on other Contech division offerings, visit www.ContechES.com or call 800.338.1122 NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS A WARRANTY. APPLICATIONS SUGGESTED HEREIN ARE DESCRIBED ONLY TO HELP READERS MAKE THEIR OWN EVALUATIONS AND DECISIONS, AND ARE NEITHER GUARANTEES NOR WARRANTIES OF SUITABILITY FOR ANY APPLICATION. CONTECH MAKES NO WARRANTY WHATSOEVER, EXPRESS OR IMPLIED, RELATED TO THE APPLICATIONS, MATERIALS, COATINGS, OR PRODUCTS DISCUSSED HEREIN. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND ALL IMPLIED WARRANTIES OF FITNESS FOR ANY PARTICULAR PURPOSE ARE DISCLAIMED BY CONTECH. SEE CONTECH’S CONDITIONS OF SALE (AVAILABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION. The product(s) described may be protected by one or more of the following US patents: 5,322,629; 5,624,576; 5,707,527; 5,759,415; 5,788,848; 5,985,157; 6,027,639; 6,350,374; 6,406,218; 6,641,720; 6,511,595; 6,649,048; 6,991,114; 6,998,038; 7,186,058; 7,296,692; 7,297,266; related foreign patents or other patents pending. 800-338-1122 www.ContechES.com cds_manual 3/17 PDF ENGINEERED SOLUTIONS August 2018 GENERAL USE LEVEL DESIGNATION FOR PRETREATMENT (TSS) For CONTECH Engineered Solutions CDS® System Ecology’s Decision: Based on the CONTECH Engineered Solutions (CONTECH) application submissions for the CDS® System, Ecology hereby issues the following use designations for the CDS storm water treatment system: 1. General Use Level Designation (GULD) for pretreatment use, as defined in Ecology’s 2011 Technical Guidance Manual for Evaluating Emerging Stormwater Treatment Technologies Technology Assessment Protocol – Ecology (TAPE) Table 2, (a) ahead of infiltration treatment, or (b) to protect and extend the maintenance cycle of a basic, enhanced, or phosphorus treatment device (e.g., sand or media filter). This GULD applies to 2,400 micron screen CDS® units sized per the table below. 2. The following table shows flowrates associated with various CDS models: CDS Model Water Quality Flow cfs L/s Precast** Inline or Offline CDS 2015-4 0.7 19.8 CDS 2015-5 0.7 19.8 CDS 2020-5 1.1 31.2 CDS2025-5 1.6 45.3 CDS3020-6 2 56.6 CDS3030-6 3 85.0 CDS3035-6 3.8 106.2 CDS4030-8 4.5 127.4 CDS4040-8 6 169.9 CDS4045-8 7.5 212.4 CDS5640-10 9 254.9 CDS5653-10 14 396.5 CDS5668-10 19 538.1 CDS5678-10 25 7.08 Offline Only CDS3030-V 3 85 Precast** CDS4030-7 4.5 127.4 CDS4040-7 6 169.9 CDS4045-7 7.5 212.4 CDS5640-8 9 254.9 CDS5653-8 14 396.5 CDS5668-8 19 538.1 CDS5678-8 25 708 CDS5042 9 254.9 CDS5050 11 311.5 CDS7070 26 736.3 CDS10060 30 849.6 CDS10080 50 1416 CDS100100 64 1812.5 Cast In Place CDS150134-22 148 4191.4 CDS200164-26 270 7646.6 CDS240160-32 300 8496.2 *Specially Designed CDS Units may be approved by Ecology on a on a site-by-site basis. **Contact Contech for updated model numbers if PMIU, PMSU, PSW, PSWC are specified. 3. The water quality design flow rates are calculated using the following procedures: Western Washington: For treatment installed upstream of detention or retention, the water quality design flow rate is the peak 15-minute flow rate as calculated using the latest version of the Western Washington Hydrology Model or other Ecology- approved continuous runoff model. Eastern Washington: For treatment installed upstream of detention or retention, the water quality design flow rate is the peak 15-minute flow rate as calculated using one of the three methods described in Chapter 2.2.5 of the Stormwater Management Manual for Eastern Washington (SWMMEW) or local manual. Entire State: For treatment installed downstream of detention, the water quality design flow rate is the full 2-year release rate of the detention facility. 4. The pretreatment GULD has no expiration date; however, Ecology may amend or revoke the designation. 5. All designations are subject to the conditions specified below. 6. Properly designed and operated CDS systems may also have applicability in other situations (example: low-head situations such as bridges or ferry docks), for TSS where, on a case-by-case basis, it is found to be infeasible or impracticable to use any other approved practice. Jurisdictions covered under the Phase I or II municipal stormwater permits should use variance/exception procedures and criteria as required by their NPDES permit. 7. Ecology finds that the CDS, sized according to the table above, could also provide water quality benefits in retrofit situations. Ecology’s Conditions of Use: CDS systems shall comply with these conditions: 1. Design, assemble, install, operate, and maintain CDS Systems in accordance with Contech’s applicable manuals and documents and the Ecology decision and conditions specified herein. Ecology recommends use of the inspection and maintenance schedule included as Attachment 1. 2. Maintenance: The required inspection/maintenance interval for stormwater treatment devices is often dependent upon the efficiency of the device and the degree of pollutant loading from a particular drainage basin. Therefore, Ecology does not endorse or recommend a “one size fits all” maintenance cycle for a particular model/size of manufactured treatment device. Owners/operators must inspect the CDS™ System for a minimum of twelve months from the start of post-construction operation to determine site-specific maintenance schedules and requirements. You must conduct inspections monthly during the wet season, and every other month during the dry season. (According to SWMMWW, the wet season for western Washington is October 1 to April 30. According to SWMMEW, the wet season in eastern Washington is October 1 to June 30). After the first year of operation, owners/operators must conduct inspections based on the findings during the first year of inspections. Conduct inspections by qualified personnel, follow manufacturer’s guidelines, and use methods capable of determining either a decrease in treated effluent flow rate and/or a decrease in pollutant removal ability. 3. Discharges from the CDS System shall not cause or contribute to water quality standards violations in receiving waters. Applicant: Contech Engineered Solutions Applicant’s Address: 11835 NE Glen Widing Drive Portland, OR 97220 Application Documents: Contech Stormwater Solutions Application to: Washington State Department of Ecology Water Quality Program for General Use Level Designation – Pretreatment Applications and Conditional Use Level Designation – Oil Treatment of the Continuous Deflective Separation (CDS™) Technology (June 2007) Strynchuk, Royal, and England, The Use of a CDS Unit for Sediment Control in Brevard County. Walker, Allison, Wong, and Wootton, Removal of Suspended Solids and Associated Pollutants by a CDS Gross Pollutant Trap, Cooperative Research Centre for Catchment Hydrology, Report 99/2, February 1999 Allison, Walker, Chiew, O’Neill, McMahon, From Roads to Rivers Gross Pollutant Removal from Urban Waterways, Cooperative Research Centre for Catchment Hydrology, Report 98/6, May 1998 Applicant’s Use Level Request: General use level designation as a pretreatment device and conditional use level designation as an oil and grease device in accordance with Ecology’s Stormwater Management Manual for Western Washington. Applicant’s Performance Claims: Based on laboratory trials, the CDS™ System will achieve 50% removal of total suspended solids with d50 of 50-μm and 80% removal of total suspended solids with d50 of 125-μm at 100% design flowrate with typical influent concentration of 200-mg/L. Ecology’s Recommendation: Ecology finds that: The CDS™ system, sized per the table above, should provide, at a minimum, equivalent performance to a presettling basin as defined in the most recent Stormwater Management Manual for Western Washington, Volume V, Chapter 6. Findings of Fact: 1. Laboratory testing was completed on a CDS 2020 unit equipped with 2400-m screen using OK-110 sand (d50 of 106-μm) at flowrates ranging from 100 to 125% of the design flowrate (1.1 cfs) with a target influent of 200 mg/L. Laboratory results for the OK-110 sand showed removal rates from about 65% to 99% removal with 80% removal occurring near 70% of the design flowrate. 2. Laboratory testing was completed on a CDS 2020 unit equipped with 2400-m screen using “UF” sediment (d50 of 20 to 30-μm) at flowrates ranging from 100 to 125% of the design flowrate (1.1 cfs) with a target influent of 200 mg/L. Laboratory results for the “UF” sediment showed removal rates from about 42% to 94% removal with 80% removal occurring at 5% of the design flowrate. 3. Laboratory testing was completed on a CDS 2020 unit equipped with 4700-m screen using OK-110 sand (d50 of 106-μm) at flowrates ranging from 100 to 125% of the design flowrate (1.1 cfs) with a target influent of 200 mg/L. Laboratory results for the OK-110 sand showed removal rates from about 45% to 99% removal with an average removal of 83.1%. 4. Laboratory testing was completed on a CDS 2020 unit equipped with 4700-m screen using “UF” sediment (d50 of 20 to 30-μm) at flowrates ranging from 100 to 125% of the design flowrate (1.1 cfs) with a target influent of 200 mg/L. Laboratory results for the “UF” sediment showed removal rates from about 39% to 88% removal with an average removal of 56.1%. 5. Contech completed laboratory testing on a CDS2020 unit using motor oil at flowrates ranging from 25% to 75% of the design flowrate (1.1 cfs) with influents ranging from 7 to 47 mg/L. Laboratory results showed removal rates from 27% to 92% removal. A spill test was also run at 10% of the design flowrate with an influent of 82,000 mg/L with an average percent capture of 94.5% 6. Independent parties in California, Florida, and Australia completed various field studies. Field studies showed the potential for the unit to remove oils and grease and total suspended solids, and capture 100% gross solids greater than the aperture size of the screen under treatment flow rate. 7. CDS Technology has been widely accepted with over 6,200 installations in the United States and Canada. There are over 1,380 installations in Washington and Oregon. Technology Description: Engineers can download a technology description from the company’s website. www.conteches.com Recommended Research and Development: Ecology encourages Contech to pursue continuous improvements to the CDS system. To that end, Ecology makes the following recommendations: 1. Conduct testing to quantify the flowrate at which resuspension occurs. 2. Conduct testing on various sized CDS units to verify the sizing technique is appropriate. 3. Test the system under normal operating conditions, pollutants partially filling the swirl concentrator. Results obtained for “clean” systems may not be representative of typical performance. Contact Information: Applicant Contact: Jeremiah Lehman Contech Engineered Solutions (503) 258-3136 jlehman@conteches.com Applicant website: http://www.conteches.com/ Ecology web link: http://www.ecy.wa.gov/programs/wq/stormwater/newtech/index.html Ecology: Douglas C. Howie. P.E. Department of Ecology Water Quality Program (360) 407-6444 douglas.howie@ecy.wa.gov Revision History Date Revision July 2008 Original use-level-designation document February 2010 Reinstate Contech’s Oil Control PULD August 2012 Revised design storm criteria, revised oil control QAPP, TER, and Expiration dates December 2012 Revised Contech Engineered Solutions Contact Information; Added QAPP for Oil Treatment May 2013 Revised model numbers in Attachment 1 April 2014 Revised Due dates for QAPP and TER and changed Expiration date August 2014 Revised Due dates for QAPP and TER and changed Expiration date July 2016 Updated Oil Control PULD to a CULD based on preliminary field monitoring results November 2016 Revised Contech Contact person August 2018 Removed CULD for Oil from document Attachment 1 CDS Stormwater Treatment Unit Checklist Frequency Drainage System Feature Problem Conditions to Check For Recommended Action Date Inspected* J F M A M J J A S O N D M & S Inlet Chamber Accumulation of trash, debris and sediment Trash blocking inlet throat opening & sediment accumulation exceeds 2 inches Remove trash, debris, and sediments. Inlet throat opening should not be blocked by any materials. A Screen Blockage/Damage Biological growth on the surface of the screen; broken screen or loose screen Powerwash screen to clean the surface and Contact CSS for screen repair (broken or loose) M Separation Chamber Trash and floatable debris accumulation Excessive trash and floatable debris accumulation on the surface in separation chamber Remove trash or other floatable debris in separation chamber to minimum level A Oil Baffle** Damaged Baffles corroding, cracking, warping, and/or showing signs of failure as determined by maintenance/inspection person. Baffles repaired or replaced to design specifications. M & S Oil sorbent** Consumed Change of color in sorbents (fresh sorbents typically appears to be white or light yellow) Remove spent oil sorbent and replace with new sorbent M Sediment Depth in the Sump Sediment accumulation Sediment accumulation exceeds 75-85% sump depth (varies depending on the Model, see attached Table) Sediment in sump should be removed using vactor truck. M Sediment Depth behind the screen Sediment accumulation Sediment accumulation exceeds 2 inches behind the screen Sediment behind the screen should be removed using vactor truck. Frequency Drainage System Feature Problem Conditions to Check For Recommended Action Date Inspected* J F M A M J J A S O N D M Access Cover (MH, Grate, cleanout) Access cover Damaged/ Not working One maintenance person cannot remove lid after applying 80 pounds of lift, corrosion of deformation of cover. Cover repaired to proper working specifications or replaced. A Inlet and Outlet Piping Damaged Piping/Leaking Any part of the pipes are crushed or damaged due to corrosion and/or settlement. Pipe repaired or replaced. A Concrete Structure Concrete structure (MH or diversion vault) has cracks in wall, bottom, and damage to frame and/or top slab. Cracks wider than ½ inch or evidence of soil particles entering the structure through the cracks, or maintenance/inspection personnel determine that the structure is not structurally sound. Structure repaired so that no cracks exist wider than 0.25 inch at the joint of inlet/outlet pipe. A Access Ladder Ladder rungs unsafe Maintenance person judges that ladder is unsafe due to missing rungs, misalignment, rust, or cracks. Ladder must be fixed or secured immediately. Ladder meets design standards and allows maintenance persons safe access. *Note dates when maintenance was performed and type of maintenance performed in notes section below. **May not be present on all units. (M) Monthly from November through April. (A) Once in late summer (preferable September) (S) After any major storm (use 1-inch in 24 hours as a guideline). If you are unsure whether a problem exists, please contact a Professional Engineer. Notes: Maintenance of CDS stormwater treatment unit typically does not require confined space entry. Visual inspections should be performed above ground. If entry is required, it should be performed by qualified personnel. Refer to CDS Unit Operation & Maintenance Guideline for maintenance details. Typically the CDS unit needs to be inspected before and after the rainfall seasons (November to April), after any major storms (>1-inch within 24 hour) and in the event of chemical spills. Contact Contech Engineered Solutions (CSS) (800-548-4667) if there is any damage to the internal components of CDS Unit. CDS Maintenance Indicators and Sediment Storage Capacities CDS Model Diameter Distance from Water Surface to Top of Sediment Pile Sediment Storage Capacity ft m ft m yd 3 m3 CDS2015 5 1.5 3.0 0.9 1.3 1.0 CDS2020 5 1.5 3.5 1.1 1.3 1.0 CDS2025 5 1.5 4.0 1.2 1.3 1.0 CDS3020 6 1.8 4.0 1.2 2.1 1.6 CDS3030 6 1.8 4.6 1.4 2.1 1.6 CDS3035 6 1.8 5.0 1.5 2.1 1.6 CDS4030 8 2.4 4.6 1.4 5.6 4.3 CDS4040 8 2.4 5.7 1.7 5.6 4.3 CDS4045 8 2.4 6.2 1.9 5.6 4.3 Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendix 5 Current Rosboro Testing Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendix 6 Geotechnical Report Foundation Engineering, Inc. Professional Geotechnical Services Memorandum 820 NW Cornell Avenue • Corvallis, Oregon 97330 • 541-757-7645 7857 SW Cirrus Drive, Bldg 24 • Beaverton, Oregon 97008 • 503-643-1541 Date: February 9, 2024 To: Dean Locke, Direction of Projects Rosboro From: Mel McCracken, P.E., G.E. Erin Gillaspie, P.E. Subject: Geotechnical Investigation Project: Rosboro Project Project No.: 2231110 We have completed the geotechnical investigation for the above-referenced project. Our findings and recommendations are summarized below. There are numerous values in geotechnical investigations that are approximate including calculated parameters, measured lengths, soil layer depths and elevations, and strength measurements. For brevity, the symbol “±” is used throughout this report to represent the words approximate or approximately when discussing these values. BACKGROUND Rosboro is planning to construct improvements at their existing facility at 2509 Main Street in Springfield, Oregon. The site location is shown in Figure 1A (Appendix A). The improvements will include replacement of an existing structure and expanding operations onto an adjacent parcel at the southwest portion of the facility. The improvements to the southwest will include a new glulam manufacturing building that will be ±220x660 feet in plan. In addition, an existing former plywood plant at the south end of the site will be demolished to accommodate a new planar building with expected dimensions of ±210x340 feet. Both facilities are expected to consist of pre-engineered metal buildings (PEMB) supported by isolated spread footings and include a slab-on-grade floor with a thickened edge. The proposed buildings are expected to include foundation loads of 20 to 200 kips. Both structures will also include either thickened slab segments or isolated mat foundations to support equipment. The site is relatively flat, and the required site grading is expected to be minor. Grading for the glulam building will require cuts of ±4 feet on the east side of the structure to provide a level building pad. Limited areas of new pavements are expected around the new building footprint to connect the new improvements to the existing pavement. The new pavements are expected to support heavy truck traffic and heavy forklift traffic moving material throughout the site. Rosboro Project February 9, 2024 Geotechnical Investigation 2. Project No.: 2231110 Springfield, Oregon Rosboro We have assumed the building occupancies will not exceed 250 persons and the buildings will not be considered “Special Occupancy Structures” per Section 1803.3.2 of the 2022 Oregon Structural Specialty Code (OSSC). Therefore, a site-specific seismic hazard investigation was not included in our scope of work. Rosboro is the project owner and kpff is the civil and structural designer. Wilson Architecture (Wilson) is the project architect. Rosboro retained Foundation Engineering as the geotechnical consultant. Our scope of work was outlined in a proposal dated October 24, 2023, and authorized by a signed Professional Services Agreement dated November 7, 2023. FIELD EXPLORATION We drilled eight exploratory borings (BH-1 through BH-8) at the site to provide subsurface information for designing the building foundations. The borings were drilled at the approximate locations shown on Figure 2A. Borings BH-1 through BH-5 were drilled in the vicinity of the planned glulam building on November 20, 2023. Boring BH-6 was attempted north of the planned planar building. However, that boring encountered a buried fire suppression line ±2.5 feet below the ground surface and was abandoned. Therefore, no boring log was generated for BH-6. However, the boring location is shown in Figure 2A. We returned to the site on December 4, 2023, and drilled two additional borings (BH-7 and BH-8) east of the planned planar building. The drilling was completed using a Canterra CT150, truck-mounted drill rig with hollow stem augers. Soil samples were obtained at 2.5-foot intervals to ±10 feet, and at 5-foot intervals thereafter. Disturbed samples were obtained with a split-spoon sampler. The Standard Penetration Test (SPT), which is run when the split-spoon is driven, provides an indication of the relative stiffness or density of the foundation soils. Relatively undisturbed Shelbey tube samples of the fine-grained soil were also obtained at selected locations and depths. The borings were continuously logged during drilling. The final logs (Appendix B) were prepared based on a review of the field logs, the laboratory test results, and an examination of the soil samples in our office. The sampling depths and SPT data for each boring are summarized on the appended logs. The boring locations were not surveyed. Therefore, ground surface elevations shown on the boring logs are based on topographic plans provided by Rosboro and are approximate. Upon completion of drilling, the boreholes were backfilled with bentonite in accordance with Oregon Water Resources Department guidelines. Outside of active work areas, the backfill was capped with crushed rock. In active work areas, the backfill was capped with asphaltic concrete (AC) cold patch. Rosboro Project February 9, 2024 Geotechnical Investigation 3. Project No.: 2231110 Springfield, Oregon Rosboro LABORATORY TESTING The laboratory testing included moisture content determinations (ASTM D2216), expansion index (ASTM D4829), and Atterberg limits (ASTM D4318) tests to help classify the soils and estimate their overall engineering properties. The results of these tests are summarized in Tables 1C and 2C (Appendix C). The moisture contents are also included on the appended logs. We classified untested soil in the field according to ASTM D2488-09A (Standard Test Method for Description and Identification of Soils (Visual-Manual Procedure)). Atterberg limits testing on the fine-grained alluvium indicates a Liquid Limit (LL) ranging from 77 to 86 and a plasticity index (PI) value ranging from 46 to 54. These values correspond to a Unified Soil Classification System (USCS) classification of CH. An expansion index test was completed on a sample of the high plasticity clay sample (SS-1-1) to evaluate the swell potential of the medium to high plasticity soils encountered at shallow depths across the site. The test consists of recording the swell potential of a remolded soil sample prepared at ±50% saturation. The amount of swell is expressed in terms of the expansive index (EI). An EI of 49 was recorded for sample SS-1-1, which empirically corresponds to a low potential for expansion. The low expansive potential assessment of the surficial fine-grained alluvium is consistent with our visual observation of the soil characteristics. In the field this material was typically described as low to medium plasticity clayey silt (ML). We attribute the higher LL and PI values and corresponding USCS classification of CH to the moisture-sensitive nature of the fine-grained alluvium. Field vane measurements were also made on Shelby tube samples of the fine-grained soils from the borings. The test results, summarized in Table 3C, indicate undrained shear strengths ranging from ±0.30 to 0.84 tons/ft2 (tsf). This corresponds to a medium stiff to stiff consistency. DISCUSSION OF SITE CONDITIONS Site Topography and Surface Conditions Most of the new planar building footprint is currently occupied by an existing building that will be demolished. The ground surface surrounding and inside the existing building is relatively flat and typically covered with AC pavement. The planned glulam manufacturing building footprint is currently a storage yard that includes AC or gravel surfacing with some areas of grass. The eastern portion of the planned glulam building footprint is elevated ±2 to 3 feet above the western portion. Rosboro Project February 9, 2024 Geotechnical Investigation 4. Project No.: 2231110 Springfield, Oregon Rosboro Subsurface Conditions A general discussion of subsurface conditions is provided in this section. A detailed description of conditions encountered in each boring (except BH-6 which encountered a shallow water line) is provided in the boring logs (Appendix B). Pavements. The borings drilled through existing pavement near the planned glulam building (i.e., BH-1 and BH-3) encountered a pavement section consisting of ±2 to 4 inches of AC followed by dense crushed gravel or crushed rock (base rock) to a depth of ±18 to 24 inches. BH-7 and BH-8, advanced through pavement on the east side of the planar building, encountered ±5 to 8 inches of AC over base aggregate extending to a depth of ±24 inches. At BH-6 on the north side of the planar building, the existing AC appeared to be ±3 to 4 inches thick. Base Aggregate (presumably associated with water line trench backfill) extended to ±2.5 feet. Site Fill. Several of the borings (BH-2, BH-4 and BH-5) were drilled in gravel surfaced areas. Our exploration in these areas typically encountered ±2 feet of crushed rock. However, BH-2 encountered granular fill, which appears to be associated with a nearby utility line. The fill at this location consisted of dense crushed gravel extending ±7 feet below the current grade. BH-4 was advanced through an existing granular pad near the northeastern portion of the glulam building. We originally attempted to drill ±25 feet north of BH-4 (as shown on Figure 2A). However, at that location the boring encountered practical drilling refusal and what appeared to be a concrete slab at a depth of ±2.5 feet. Based on observation of return cuttings and the action of the rig, the fill encountered at that location above the presumed slab consisted of predominantly crushed rock to ±2 feet, followed by predominantly fine-grained soil from ±2 to 2.5 feet (the depth of the slab). The crushed rock encountered at BH-4 is underlain by additional site fill consisting of silt with debris consisting of brick and concrete fragments extending to a depth of ±3.5 feet. The granular fill encountered below ±2 feet at BH-5 includes some organics extending to ±4 feet. Predominantly fine-grained fill was encountered beneath the pavement section in BH-7 and BH-8 extending to depths of ±3 to 4 feet. The fill is soft to medium stiff and contains organics at some locations. Silty Clay (alluvium – Willamette Silt). Brown to dark brown, medium to high plasticity silty clay was typically encountered beneath the pavement section or any site fill in all borings. The silty clay extends to the underlying sandy gravel at depths ranging from ±8.5 to 14.5 feet (±El. 460.5 to 464). The silty clay stratum extends across the Willamette Valley. The material is typically referred to as Willamette Silt, although the primary constituent is clay in some geographic areas. At some boring locations, we noted fine sand near the contact with the underlying sandy gravel. Rosboro Project February 9, 2024 Geotechnical Investigation 5. Project No.: 2231110 Springfield, Oregon Rosboro SPT N-values recorded in the Willamette Silt were typically in the range of 5 to 20, suggesting a medium stiff to very stiff consistency. Field vane shear tests completed on relatively undisturbed Shelby tube samples indicate the soil has an undrained shear strength ranging from 0.4 tons/ft2 (tsf) to 0.8 tsf, suggesting a medium stiff to stiff consistency. The results of the vane shear tests were used to describe soil consistency on the log and were also used to develop the recommended bearing resistance for spread footing design. Sandy Gravel (alluvium). Grey, wet, sandy gravel extends below the Willamette Silt. SPT N-values ranging from 33 to practical refusal (i.e., greater than 50 blows for a 6-inch increment of drive) were recorded in the gravel, suggesting the coarse-grained alluvium is dense to very dense. Groundwater We observed groundwater infiltration during drilling at depths ranging from ±8.5 to 13.5 feet. Local well logs available from the Oregon Water Resources Department (OWRD) website suggest the static groundwater level in the project vicinity lies ±6 to 10 feet below the ground surface. Therefore, we anticipate the depth of the groundwater will fluctuate seasonally between this range of depths. Iron-staining of the near-surface soils suggest water may also perch at shallower depths during periods of extended rainfall. DISCUSSION OF GEOTECHNICAL ISSUES A general discussion of geotechnical issues is provided in this section. Specific construction recommendations for these items are provided in the recommendations section. Construction Timing Our field exploration and results of the laboratory moisture content tests indicate the soils beneath the pavement are wet of their optimum moisture content for compaction. In our experience, soils beneath pavements often stay wet and are softer near the contact with the base rock, even during summer. Therefore, contractors should anticipate moist subgrade conditions into summer months. These soils may be more sensitive to disturbance and pumping under construction traffic. Subgrade soils that are too wet for compaction should be overexcavated and replaced with compacted Base Aggregate, as defined in the recommendations section. The construction schedule indicates the bulk of the earthwork will occur in August, 2024. Subgrade compaction will only be feasible during dry weather (typically mid-June to mid-October). During wet weather, thickened building pad and base rock sections are required to help protect the subgrade from construction traffic and activities. Rosboro Project February 9, 2024 Geotechnical Investigation 6. Project No.: 2231110 Springfield, Oregon Rosboro Demolition and Building Pad Construction The existing building and surrounding pavements at the planar building will be demolished to accommodate the new structure. We recommend removing all existing concrete footings and construction debris from the building footprints. Demolition of existing structure and pavements is expected to result in disturbance to the upper portion of the existing soil profile. The building pad footprint should be excavated as required to remove debris. It may be practical to limit the excavation to the upper granular fill in portions of the building pad excavation. We recommend the planar building pad be excavated to accommodate 8 inches of Base Aggregate in areas of stable existing granular fill. Areas of fine-grained soil or yielding granular soils are expected to require excavation extending ±2.5 feet below bottom of slab level to bypass the upper fill and provide an adequate granular pad. Final excavation to fine-grained subgrade should be completed using an excavator equipped with a smooth-edged bucket to minimize subgrade disturbance. The compaction and stability of existing granular fill will require field confirmation at the time of construction. Likewise, the suitability of fine-grained subgrade soils should be confirmed during excavation. The actual excavation depth should be evaluated and confirmed by a Foundation Engineering representative during construction. Limited portions of the planar building are expected to include recompaction of suitable, existing granular fill. We do not believe that it will be practical to reuse any of the on-site granular materials during final grading or backfilling. Therefore, we anticipate that all excavated materials will be hauled from the site. The improvements are expected to require imported Base Aggregate to support foundations, building pads and pavements. The glulam building pad excavation is expected to extend through the upper fill over most of the footprint to expose stiff Willamette Silt at the subgrade level. Therefore, we have assumed the subgrade would consist of compacted fill or stiff silt. We anticipate a minimum of 12 inches of Base Aggregate would be required to support the glulam building pad during dry weather conditions. We recommend the thickness of Base Aggregate be increased to 24 inches if the building will need to accommodate construction or heavy construction traffic during wet weather months. Anticipated Foundation Conditions We understand the finish floor elevations for the new planar building will lie near existing grades and the glulam building will require cuts into the east portion of the site to accommodate the proposed finished floor elevation. The borings encountered a general subsurface profile that includes pavement/fill underlain by fine-grained alluvium followed by relatively dense coarse-grained alluvium. Based on the conditions encountered in the borings, we anticipate the glulam building pad will be underlain by native, stiff Willamette Silt. Rosboro Project February 9, 2024 Geotechnical Investigation 7. Project No.: 2231110 Springfield, Oregon Rosboro However, the planar building includes fill extending ±3 to 4 feet below existing grades. Therefore, we recommend that all foundation excavations plan to extend at least 4 feet below finished grades. We have concluded conventional spread and continuous footings will be suitable to support the new structures with the following site preparation. Atterberg limits testing suggest the native, fine-grained soils are moisture sensitive and likely to vary in sensitivity across the building areas. Therefore, care will be required during subgrade preparation. We anticipate mitigation of any subgrade soils with moderate to high expansive potential, if encountered at the time of construction, will consist of overexcavation and replacement with additional Base Aggregate. SEISMIC DESIGN Seismic Response Spectrum A site response spectrum was developed for the parcel in accordance with the Oregon Structural Specialty Code (OSSC, 2022), which is based on Section 1613 of the International Building Code (IBC, 2021). The design maximum considered earthquake ground motion maps in the IBC (2021) are based on modified USGS (2014) maps with a 2% probability of exceedance in 50 years (i.e., a ±2,475-year return period). The modifications include factors to adjust the spectral accelerations to account for directivity and risk. Based on a review of well logs available from the Oregon Water Resources Department (OWRS) website, our previous work in the area, and conditions encountered in the borings, we have concluded a Site Class C (very dense soil and soft rock) is appropriate for the site. The seismic design parameters and OSSC response spectrum are shown on Figure 3A. Liquefaction Liquefiable soils typically consist of loose sands and non-plastic to low plasticity silt (i.e., silts with a Plasticity Index (PI) less than 8) that are below the water table. The site is expected to include a relatively shallow groundwater level throughout the year. The soils encountered in the borings consist of predominantly stiff, medium to high plasticity silty clay and dense to very dense sandy gravel. The fine-grained soil is not expected to liquefy under earthquake loading based on the stiffness and plasticity of the soil. The gravels are also not considered susceptible to liquefaction due to their density. Therefore, we believe that the liquefaction risk is very low. Rosboro Project February 9, 2024 Geotechnical Investigation 8. Project No.: 2231110 Springfield, Oregon Rosboro ENGINEERING ANALYSIS Bearing Capacity We anticipate new footings will bear on compacted Base Aggregate overlying stiff, undisturbed subgrade consisting of fine-grained alluvium. For the bearing capacity analysis, we used a presumptive undrained shear strength value of 800 lb/ft2 (psf) based on vane shear test results and observation of the consistency of soil samples. We also assumed dimensions of up to 6x6 feet for spread footings and widths of 2 to 3 feet for continuous wall footings. Our analysis indicates an allowable bearing pressure of 2,000 psf would be appropriate for footing design, using a factor of safety of 3. This value assumes the footings will be underlain by at least 12 inches of Base Aggregate extending at least 12 inches beyond the footing edge. The allowable bearing pressures may be increased by one-third for transient (seismic and wind) loads. Settlement No formal settlement analysis was completed based on the relatively light foundation loads of the new structures. Based on the stiffness of the foundation soils and the recommended bearing pressure, we anticipate the total and differential movements will be less than ±1 inch and ±¾ inch, respectively, if foundation preparation is completed as recommended herein. Sliding Coefficient and Passive Resistance for Footings A coefficient of friction of 0.5 between the base of the footing and the Base Aggregate may be used for sliding analysis. An equivalent fluid density of ±145 lb/ft3 (pcf) may be used to represent the potential passive resistance against the vertical face of the thickened edge footing. The passive resistance assumes limited horizontal movement (i.e., less than ±1 inch) for service-level design. This allowable value assumes all footings will be backfilled with compacted Base Aggregate. Slab-on-Grade Reinforced concrete slab-on-grade floors are planned for the new buildings. The slabs will support heavy concentrated wheel loads as well as some equipment foundations. We recommend the glulam floor slabs be supported on a minimum of 12 inches of compacted Base Aggregate underlain by compacted subgrade soil. Therefore, a modulus of subgrade reaction (ks) of 250 lb/in3 (pci) is appropriate for design of slabs for the glulam building. If suitable existing granular fill is encountered at the planar building, we recommend compacting the subgrade and supporting the floor slabs on a minimum of 8 inches of compacted Base Aggregate. Therefore, a reduced modulus of subgrade reaction (ks) of 200 pci is appropriate for design of planar building slabs. Rosboro Project February 9, 2024 Geotechnical Investigation 9. Project No.: 2231110 Springfield, Oregon Rosboro Retaining Wall Design and Construction The planned improvements are expected to include retaining walls up to ±5 feet high east of the glulam building. The walls will include relatively level backfill at the base and may include slightly sloping terrain at the top of the wall. We assumed a maximum slope of 14 degrees for our analysis. To determine lateral earth pressures from backfilling, we assumed that the backfill will consist of Base Aggregate with an in-place unit weight of 125 pcf and a minimum internal friction angle of 34 degrees. Drained conditions were also assumed. We estimated the lateral earth pressure against the retaining wall using a Rankine active earth pressure coefficient (ka) of 0.33. Therefore, we recommend using an equivalent fluid density of 41 lb/ft3 (pcf) when estimating the static lateral earth pressure on the walls. The walls should also be designed to account for a surcharge from traffic operating behind the walls. AASHTO recommends designing walls for a traffic surcharge pressure of at least 250 psf if traffic will be maintained at least 1 foot from the wall. Therefore, using the active earth pressure coefficient (ka) of 0.33, a lateral earth pressure of 83 psf should be considered for surcharge. If the traffic surcharge (e.g., wheel loads or outriggers) may extend within 1 foot of the wall, the design should include a minimum surcharge pressure of 625 psf, corresponding to a lateral earth pressure of 206 psf. The walls should be backfilled with granular soil and a foundation drain should be provided to limit the development of hydrostatic pressures behind the walls. Equipment used to compact the backfill should be limited to small, walk-behind equipment adjacent to the wall to prevent overstressing. Drainage The static groundwater table is expected to be below the current limits of grading and excavations. However, water may perch on the near-surface soils during periods of extended rainfall and elevated groundwater conditions may occur during the wet, winter months. Based on the anticipated site grading plan, the soil conditions encountered in the borings, and the expected drainage characteristic of the soil, we recommend providing perimeter drainage around the new buildings. The ground surface around the buildings should also be graded to promote runoff away from new foundations. Foundation drainage may be omitted if the new buildings are surrounded by hardscape surfaces that abut the buildings. Foundation drains should be provided for all retaining walls. Rosboro Project February 9, 2024 Geotechnical Investigation 10. Project No.: 2231110 Springfield, Oregon Rosboro PAVEMENT SECTIONS (RIGID AND FLEXIBLE PAVEMENTS) The predominantly fine-grained subgrade will be moisture-sensitive and susceptible to softening, pumping, and rutting under construction traffic when wet. Wet weather construction will likely require providing a thickened base rock section or granular subbase to reduce the risk of pumping. We should be contacted to provide wet weather construction recommendations if the earthwork and roadway construction is delayed into the winter months. Dry weather pavement construction is recommended to the extent practical. We anticipate that pavement areas may be prepared one of two following ways, based on the subgrade conditions exposed: 1) If suitable granular fill is exposed at the subgrade level, compact the surface and cover with compacted Base Aggregate. 2) If stiff fine-grained soil is exposed at the subgrade level, place and compact a gravel subbase over the relatively undisturbed subgrade and cover with compacted Base Aggregate. If unsuitable soil is exposed at the planned subgrade elevation, overexcavation and replacement with additional imported granular fill will be required, similar to Option 2. Estimated Traffic Rosboro indicated the primary traffic will consist of Hyster 210 forklifts weighing 30 kips (unloaded). It is anticipated that the forklifts will operate up to 16 hours per day and may make a pass every 2.5 minutes. The carrying capacity of the forklifts is 20 kips, which is consistent with the reported weight of the anticipated loads. Based on the assumed traffic for the facility, we estimated an Average Daily Traffic (ADT) that includes a forklift distribution consisting of 60% unloaded, 25% partially loaded (44 kips) and 15% fully loaded. We also considered additional conventional truck traffic. Using the assumed traffic and Equivalent Single-Axle Loading (ESAL) conversion factors based on AASHTO design standards, we calculated ±31,000,000 ESALs for a 20-year pavement design life. Subgrade and Base Rock Design Parameters The bulk of the new pavement areas are expected to be constructed over firm, compacted subgrade. Subgrade conditions are expected to vary with location and may include stiff, native Willamette Silt or granular fill. For pavement design, we assumed a resilient modulus (MR) of 6,000 lb/in2 (psi), based on our experience with stiff clay subgrade. We assumed a MR of 20,000 psi for new Base Aggregate, based on ODOT recommendations. Rosboro Project February 9, 2024 Geotechnical Investigation 11. Project No.: 2231110 Springfield, Oregon Rosboro Rigid Pavement Design Portland Cement Concrete (PCC) pavements are expected at aprons and other high traffic areas at the facility. Rigid pavement design was completed based on AASHTO design methods (AASHTO, 1993). We assumed Jointed Plain Concrete Pavement (JPCP) would be used. Our calculations assumed typical design parameters for plain concrete pavements in the area and the subgrade conditions observed. Based on the estimated forklift and truck volume and distribution, we recommend a minimum 12-inch PCC thickness. The new PCC should be underlain by at least 12 inches of Base Aggregate where the pavements are underlain by fine-grained subgrade. Flexible Pavement Design We completed flexible pavement design generally using the ODOT design method with the assumed traffic and Mr values discussed above. Our analysis indicates a minimum flexible pavement section consisting of 9 inches of asphaltic concrete (AC) over 19 inches of Base Aggregate for a 20-year design life. RECOMMENDATIONS Based on the anticipated construction schedule, the bulk of the earthwork is expected to occur during dry weather months. However, some portions of the work may extend into wet conditions. Therefore, the recommendations provided below include contingencies for both dry and wet weather construction techniques. Material Specifications and Compaction Requirements 1. Base Aggregate should consist of 1”-0 or ¾”-0 crushed aggregate that is durable, well-graded, and relatively clean (i.e., with less than 5% passing the No. 200 sieve). We should be provided a gradation sheet for the Base Aggregate for approval prior to delivery to the site. 2. Stabilization Rock should consist of clean, angular, 3” open-graded rock. The Stabilization Rock should include less than 10% (by weight) passing the ¼” sieve and less than 2% passing the No. 200 sieve. 3. Drain Rock should consist of 2-inch diameter, clean (less than 2% passing the #200 sieve), open-graded, crushed gravel or rock. The actual gradation and maximum aggregate size will depend on the availability from local suppliers. We should be provided a gradation curve of the intended fill for approval, prior to delivery to the site. 4. The subgrade should consist of predominantly low to medium plasticity fine-grained soil that does not contain abundant organics, debris, or high plastic clay. Existing granular fill will require review and approval at the time of construction. The subgrade is moisture sensitive and will require careful treatment throughout demotion, excavation, and building pad preparation. Rosboro Project February 9, 2024 Geotechnical Investigation 12. Project No.: 2231110 Springfield, Oregon Rosboro 5. Site stripping should remove the upper pavements and surface soil that contains the bulk of the demolition debris, organics, and softened soil. Deeper excavation may be required in some areas (e.g., to remove abandoned utilities or footings). 6. The Separation Geotextile should meet the minimum requirements of an AASHTO M 288-17 geotextile for separation and have Mean Average Roll Value (MARV) strength properties meeting the requirements of an AASHTO M 288-17 Class 2, woven geotextile. We should be provided a specification sheet on the selected geotextile for approval prior to delivery to the site. 7. Drainage Geotextile should consist of a non-woven geotextile with a grab tensile strength greater than 200 lb., an apparent opening size (AOS) of between #70 and 100 (US Sieve), and a permittivity greater than 0.1 sec-1. 8. Subgrade compaction is expected to require a large pad foot or kneading roller to compact the fine-grained soil. Compaction should be completed using multiple passes of the roller over the moisture-conditioned subgrade. Final subgrade preparation may require trimming the surface or compacting the subgrade using a smooth drum roller to provide a firm, uniform surface. Granular fill subgrade is expected to compact more efficiently using a vibratory, smooth drum roller. All compacted subgrades should be compacted to at least 95% relative compaction according to ASTM D698. Documentation of the subgrade compaction is expected to include variable materials and should include observation by the engineer and proof rolling of the compacted surface using a 10-yd3 dump truck, or other suitable sized piece of construction equipment. Areas of pumping or deflection observed beneath the truck wheels may be reworked, or overexcavated and replaced with compacted Base Aggregate and proof-rolled again. Do not attempt to compact the subgrade during wet weather. 9. Moisture-condition and compact the Base Aggregate in loose lifts not exceeding 12 inches. Thinner lifts may be required if light or hand-operated equipment is used. Compact the Base Aggregate to a minimum of 95% relative compaction. The maximum dry density of ASTM D698 should be used as the standard for estimating relative compaction. Field density tests should be completed on the compacted Base Aggregate to confirm adequate compaction. The completed building pad should also be proof-rolled using a loaded, 10-yd3 dump truck or another approved vehicle. Rosboro Project February 9, 2024 Geotechnical Investigation 13. Project No.: 2231110 Springfield, Oregon Rosboro 10. Inform contractors that water infiltration may occur in utility excavations deeper than ±7 feet. Assume water will be encountered at shallower depths during the winter months. Trenches should be pumped dry prior to placing backfill. Trench backfill that extends beneath the new building should consist of Base Aggregate placed and compacted as specified in Item 9. 11. Provide contractors with a copy of this memorandum to review recommendations for site preparation and foundation construction, and the soil conditions encountered in the borings. We should be provided an opportunity to meet with the contractor prior to construction to discuss the site conditions, construction schedule and the contractor’s approach to site preparation. Building Pad Preparation and Foundation Construction Site preparation and foundation construction for the buildings should be completed as follows: 12. Remove all existing concrete, pavements, and landscaping from the building areas. Haul all debris from the site. 13. Excavate during dry weather to the required grade to provide a minimum 12-inch thick building pad for the glulam building and a minimum 8-inch thick building pad for the planar building. Moisture-condition and compact the subgrade as recommended in Item 8. Areas of the planar building that cannot be stabilized are expected to require an additional 2 feet of excavation and replacement with Base Aggregate. Therefore, we recommend a unit cost will be included in the bid documents for additional excavation and rock placement. During wet weather, excavate as necessary to provide a minimum of 24 inches of Base Aggregate over stiff, uncompacted subgrade. Soft subgrade exposed during wet weather should be mitigated by overexcavating to firm soil or using Stabilization Rock in the lower 12 inches of the 24-inch thick building pad. 14. Use Base Aggregate to backfill all plumbing and utility trenches within the building pad. Compact the trench backfill in lifts as recommended. Complete final grading and surface compaction of the slab area after all trenching and footing excavation are complete. 15. Excavate for footings using an excavator equipped with a smooth-edged bucket to minimize subgrade disturbance. The excavation depth should accommodate 18 inches of compacted Base Aggregate beneath the footings at the glulam building. Deeper excavation depths are anticipated at the planar building to bypass the fill. Therefore, a nominal 24 inches of Base Aggregate should be anticipated. Rosboro Project February 9, 2024 Geotechnical Investigation 14. Project No.: 2231110 Springfield, Oregon Rosboro The fill under the foundations should extend a minimum of 12 inches beyond the edge of the footing. The excavation distance should be increased to 18 inches at the planar building where deeper Aggregate Base is required. The fill should extend the full width of the footing excavation if thickened edge foundations are used. 16. Place and compact in lifts the required thickness of Base Aggregate to construct the building pads. The initial lift of Base Aggregate during wet weather may be increased to 18 inches to help protect the subgrade. The subgrade soils are moisture sensitive and should be protected from construction traffic throughout placement and building pad preparation work. Foundation Design 17. Design the perimeter strip footings and isolated column footings using an allowable bearing pressure of 2,000 psf. Provide a minimum footing width of 18 inches for the perimeter footings and 24 inches for isolated column footings. 18. Assume the new buildings could experience total and differential movements (i.e., settlement, heave, or a combination thereof) of 1 inch and ¾ inch, respectively, if foundation preparation is completed as recommended herein. 19. Use a coefficient of friction of 0.5 for new footings bearing on Base Aggregate for sliding analysis. A passive resistance against the vertical face of the footing of 145 pcf (equivalent fluid density) may be assumed in combination with the base friction. 20. Design new structures using the response spectrum, Site Class, and seismic parameters summarized in Figure 3A. 21. Use a modulus of subgrade reaction, ks, of 250 pci, for the glulam building floor slab design. This value assumes the slabs will be underlain by at least 12 inches of compacted Base Aggregate placed over compacted subgrade. Use a modulus of subgrade reaction, ks, of 200 pci, for the planar building floor slab design. This value assumes the slabs will be underlain by at least 8 inches of compacted Base Aggregate placed over compacted granular fill subgrade. 22. Design retaining walls using an equivalent fluid density of 41 pcf to model lateral earth pressures on the walls, which are expected to be flexible (active earth pressures). The walls should also be designed for a surcharge pressure of at least 250 psf. Using the active earth pressure coefficient (ka) of 0.33, a uniform, lateral earth pressure of 83 psf should be considered for surcharge. The lateral earth pressure should be increased to 206 psf if traffic extends within 12 inches of the wall face. Rosboro Project February 9, 2024 Geotechnical Investigation 15. Project No.: 2231110 Springfield, Oregon Rosboro 23. Provide a suitable vapor barrier under the slabs that is compatible with the proposed floor covering and the method of slab curing. The type and placement of the vapor barrier depends on the method of slab. Therefore, this item should be reviewed by the flooring manufacturer, contractor, and project engineer and/or architect. Foundation Drainage 24. Install foundation drains along the perimeter of the new buildings and behind new retaining walls. The drains should consist of 3 or 4-inch diameter, perforated or slotted, PVC pipe wrapped in Drainage Geotextile. The pipe should be set at the base of the perimeter footing or wall foundation. The pipe should be bedded in at least 4 inches of Drain Rock and backfilled full depth with Drain Rock. The entire mass of Drain Rock should be wrapped in a Drainage Geotextile that laps at least 12 inches at the top. 25. Provide clean-outs at appropriate locations for future maintenance of the drainage system. 26. Discharge the water from the drain system into the nearest catch basin, manhole, or storm drain. Pavement Design and Construction New parking and access pavements will be constructed for the new buildings. Pavement preparation and construction should be completed as follows: 27. Demolish and remove existing structures and pavements in the areas of planned new pavements as required. Excavate existing materials to the design subgrade level. 28. During dry weather, moisture-condition and compact the subgrade as recommended in Item 8. Proof-roll the compacted subgrade using a loaded 10-yd3 dump truck to identify any soft or pumping areas. Soft or pumping subgrade identified during the proof-roll may be moisture-conditioned and recompacted or overexcavated and replaced with Base Aggregate. 29. Do not attempt to compact the subgrade during wet weather. During wet weather, excavate as required to provide a minimum of 24 inches of base rock consisting of Base Aggregate over stiff, undisturbed subgrade. The final excavation should be completed using an excavator equipped with a smooth bucket operating from outside of the excavation to minimize subgrade disturbance. Do not proof-roll the subgrade during wet weather. Rosboro Project February 9, 2024 Geotechnical Investigation 16. Project No.: 2231110 Springfield, Oregon Rosboro 30. Place a Separation Geotextile over the approved subgrade. The geotextile should be laid smooth, without wrinkles or folds. Overlap adjacent rolls a minimum of 2 feet. Pin fabric overlaps or place the building pad fill in a manner that will not separate the overlap during construction. Seams that have separated will require removal of the building pad fill to establish the required overlap. 31. Place Base Aggregate over the Separation Geotextile to construct the base rock section. The fill should be end-dumped outside the pavement area and pushed over the Separation Geotextile using a dozer. Compact the Base Aggregate as recommended in Item 9. 32. Provide a minimum flexible pavement section consisting of 9 inches of AC over 19 inches of Base Aggregate. The Base Aggregate section is intended to support limited construction traffic required for paving. We have assumed that the bulk of the construction traffic would use the existing pavement. 33. Provide a PCC thickness of 12 inches at locations subject to heavy forklift traffic. The PCC should be built over at least 12 inches of Base Aggregate and a Separation Geotextile over compacted subgrade. 34. Gravel surfaced areas that will support occasional heavy traffic should consist of a minimum of 24 inches of Base Aggregate over a Separation Geotextile and compacted subgrade. 35. Provide a minimum of 12 inches of compacted Base Aggregate under all isolated concrete slabs, or other hardscapes. Increase the minimum Base Aggregate thickness to 24 inches during wet weather, or for any areas that will be traversed by construction traffic. DESIGN REVIEW/CONSTRUCTION OBSERVATION/TESTING We should be provided the opportunity to review all drawings and specifications that pertain to site preparation and foundation construction. Site preparation will require field confirmation of subgrade conditions under the foundations, building pads and new pavements. Mitigation of any subgrade pumping will also require engineering review and judgment. That judgment should be provided by one of our representatives. Frequent field density tests should be run on all building pad fill. We recommend that we be retained to provide the necessary construction observation. Rosboro Project February 9, 2024 Geotechnical Investigation 17. Project No.: 2231110 Springfield, Oregon Rosboro VARIATION OF SUBSURFACE CONDITIONS, USE OF THIS REPORT AND WARRANTY The analysis, conclusions, and recommendations contained herein are based on the assumption that the soil profiles and the groundwater conditions observed during our field exploration are representative of the overall site conditions. The above recommendations assume that we will have the opportunity to review final drawings and be present during construction to confirm assumed foundation conditions. No changes to the enclosed recommendations should be made without our approval. We will assume no responsibility or liability for any engineering judgment, inspection or testing performed by others. This report was prepared for the exclusive use of Rosboro and their design consultants for the Rosboro Project in Springfield, Oregon. Information contained herein should not be used for other sites or for unanticipated construction without our written consent. This report is intended for planning and design purposes. Contractors using this information to estimate construction quantities or costs do so at their own risk. Climate conditions in western Oregon typically consist of wet weather for almost half of the year (typically between mid-October and late May). The recommendations for site preparation are not intended to represent any warranty (expressed or implied) against the growth of mold, mildew or other organisms that grow in a humid or moist environment. Our services do not include any survey or assessment of potential surface contamination or contamination of the soil or ground water by hazardous or toxic materials. We assume that those services, if needed, have been completed by others. Our work was done in accordance with generally accepted soil and foundation engineering practices. No other warranty, expressed or implied, is made. It has been a pleasure assisting you with this phase of your project. Please do not hesitate to contact us if you have any questions or need further information. Attachments Rosboro Project February 9, 2024 Geotechnical Investigation 18. Project No.: 2231110 Springfield, Oregon Rosboro REFERENCES ASCE, 2016, ASCE 7-16, Minimum Design Loads and Associated Criteria for Buildings and Other Structures, American Society of Civil Engineers (ASCE). AASHTO, 1993, AASHTO Guide for Design of Pavement Structures: American Association of State Highway and Transportation Officials (AASHTO). IBC, 2021, International Building Code (IBC): International Code Council, Inc., Sections 1613 and 1803. OSSC, 2022, Oregon Structural Specialty Code (OSSC): Based on the International Code Council, Inc., 2021 International Building Code (IBC), Section 1613 and 1803. USGS, 2014, Earthquake Hazards Program, Interactive Deaggregations, Dynamic Conterminous U.S. 2014 (v.4.2.0): U.S. Geological Survey (USGS), 2% in 50 years return period (2,475 years) PGA spectral acceleration, latitude/longitude search, reference material has no specific release date, accessed May 2022, website: https://earthquake.usgs.gov/hazards/interactive/index.php. Appendix A Figures Foundation Engineering, Inc. Professional Geotechnical Services DRAFT DRAFT BH-1BH-7BH-8BH-6BH-4BH-5BH-2BH-3200100SCALE IN FEET050BH-1BORING NUMBER AND LOCATIONLEGENDFoundation Engineering, Inc.Professional Geotechnical ServicesPROJECT NO.FIGURE NO.DRAWN BY:DATE:BORING LOCATIONSROSBORO PROJECTSPRINGFIELD, OREGONERIN22311102ADEC 2023DRAFT Foundation Engineering, Inc. Professional Geotechnical Services Dec. 5, 2023 PROJECT NO. FIGURE NO. DRAWN BY:DATE: OSSC 2022 SITE RESPONSE SPECTRUM ROSBORO PROJECT SPRINGFIELD, OREGONEJG2231110 3A DRAFT Appendix B Boring Logs Foundation Engineering, Inc. Professional Geotechnical Services DRAFT Foundation Engineering, Inc.Professional Geotechnical Services EXPLORATION LOGS SYMBOL KEY DISTINCTION BETWEEN FIELD LOGS AND FINAL LOGS A field log is prepared for each boring or test pit by our field representative. The log contains information concerning sampling depths and the presence of various materials such as gravel, cobbles, and fill, and observations of ground water. It also contains our interpretation of the soil conditions between samples. The final logs presented in this report represent our interpretation of the contents of the field logs and the results of the sample examinations and laboratory test results. Our recommendations are based on the contents of the final logs and the information contained therein and not on the field logs. VARIATION IN SOILS BETWEEN TEST PITS AND BORINGS The final log and related information depict subsurface conditions only at the specific location and on the date indicated. Those using the information contained herein should be aware that soil conditions at other locations or on other dates may differ. Actual foundation or subgrade conditions should be confirmed by us during construction. TRANSITION BETWEEN SOIL OR ROCK TYPES The lines designating the interface between soil, fill or rock on the final logs and on subsurface profiles presented in the report are determined by interpolation and are therefore approximate. The transition between the materials may be abrupt or gradual. Only at boring or test pit locations should profiles be considered as reasonably accurate and then only to the degree implied by the notes thereon. SH - 3 - 4 Bottom of Sample Attempt Unrecovered Portion Boring or Test Pit Number Recovered Portion Top of Sample Attempt Sample Type Sample Number SAMPLE OR TEST SYMBOLS C - Pavement Core Sample CS - Rock Core Sample OS - Oversize Sample (3-inch O.D. split-spoon) S - Grab Sample SH - Thin-walled Shelby Tube Sample SS - Standard Penetration Test Sample (2-inch O.D. split-spoon) Standard Penetration Test Resistance equals the number of blows a 140 lb. weight falling 30 in. is required to drive a standard split-spoon sampler 1 ft. Practical refusal is equal to 50 or more blows per 6 in. of sampler penetration. Water Content (%) UNIFIED SOIL CLASSIFICATION SYMBOLS G - Gravel S - Sand M - Silt C - Clay Pt - Peat W - Well Graded P - Poorly Graded L - Low Plasticity H - High Plasticity O - Organic FIELD SHEAR STRENGTH TEST Shear strength measurements on test pit side walls, blocks of soil or Shelby tube samples are typically made with Torvane or Field Vane shear devices TYPICAL SOIL/ROCK SYMBOLS WATER TABLE Water Table Location Date of Measurement(1/31/16) Concrete Organics Clay Gravel Silt Sand Sandstone Basalt Siltstone DRAFT Foundation Engineering, Inc.Professional Geotechnical Services COMMON TERMS SOIL DESCRIPTIONS Explanation of Common Terms Used in Soil Descriptions Field Identification Choesive Soils Granular Soils SPT*Su** (tsf)Term SPT* Term Easily penetrated several inches by fist.0 - 2 < 0.125 Very Soft 0 - 4 Very Loose Easily penetrated several inches by thumb.2 - 4 0.125 - 0.25 Soft 4 - 10 Loose Can be penetrated several inches by thumb with moderate effort.4 - 8 0.25 - 0.50 Medium Stiff 10 - 30 Medium Dense Readily indented by thumb but penetrated only with great effort.8 - 15 0.50 - 1.0 Stiff 30 - 50 Dense Readily indented by thumbnail.15 - 30 1.0 - 2.0 Very Stiff > 50 Very Dense Indented with difficulty by thumbnail.> 30 > 2.0 Hard Term Soil Moisture Field Description Dry Absence of moisture. Dusty. Dry to the touch. Damp Soil has moisture. Cohesive soils are below plastic limit and usually moldable. Moist Grains appear darkened, but no visible water. Silt/clay will clump. Sand will bulk. Soils are often at or near plastic limit. Wet Visible water on larger grain surfaces. Sand and cohesionless silt exhibit dilatancy. Cohesive soil can be readily remolded. Soil leaves wetness on the hand when squeezed. Soil is wetter than the optimum moisture content and above the plastic limit. Term PI Plasticity Field Test Non-plastic 0 - 3 Cannot be rolled into a thread at any moisture. Low Plasticity 3 - 15 Can be rolled into a thread with some difficulty. Medium Plasticity 15 - 30 Easily rolled into thread. High Plasticity > 30 Easily rolled and re-rolled into thread. Term Soil Structure Criteria Stratified Alternating layers at least ¼ inch thick. Laminated Alternating layers less than ¼ inch thick. Fissured Contains shears and partings along planes of weakness. Slickensided Partings appear glossy or striated. Blocky Breaks into small lumps that resist further breakdown. Lensed Contains pockets of different soils. Term Soil Cementation Criteria Weak Breaks under light finger pressure. Moderate Breaks under hard finger pressure. Strong Will not break with finger pressure. * SPT N-value in blows per foot (bpf) ** Undrained shear strength DRAFT Capped withgravel Backfilled with bentonite chips Groundwaterencountered during drilling SS-1-1 SS-1-2 SH-1-3 SS-1-4 SS-1-5 ASPHALTIC CONCRETE (±2 inches). Dense silty CRUSHED ROCK (GM); grey-brown, moist,±2-inch minus angular rock, (base rock). Medium stiff silty CLAY (CH); brown and iron-stained,moist, medium to high plasticity, (Willamette Silt). Stiff below ±5 feet. Field vane on SH-1-3: Su= 0.74 tsf at ±7.5 feet. Very dense sandy GRAVEL, trace silt (GW); grey-brownand iron-stained, wet, fine to coarse sand, fine to coarsesubrounded to rounded gravel, (alluvium). BOTTOM OF BORING 471.8 0.2 470.5 1.5 463.5 8.5 455.5 16.5 SPT N-Value Moisture (%)Groundwater Log Depth Depth and Comments Core Recovery (%) RQD (%) 0 50 100 Elev.Backfill/ Installations/(ft) Sample Number and Location Soil / Rock Description 2231110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 BORING LOG: BH-1Project No.: Surface Elevation: Date of Boring: November 20, 2023 Rosboro Project Springfield, Oregon BH-1 Page 1 of 1 472.0 feet (Approx.) Professional Geotechnical Services Foundation Engineering, Inc. 6 10 67 65 6 10 67 65 DRAFT Backfilledwith bentonitechips No seepageor groundwaterencountered during drilling S-2-1 SS-2-2 SS-2-3 SS-2-4 Dense CRUSHED GRAVEL (GP); grey, moist, up to ±1to 2-inch diameter subrounded to rounded gravel, (fill). Stiff silty CLAY (CH); brown and iron-stained, wet,medium to high plasticity, (Willamette Silt). Very dense sandy GRAVEL, trace silt (GW); grey-brown,wet, fine to coarse sand, fine to coarse subrounded torounded gravel, (alluvium). BOTTOM OF BORING 466.0 7.0 463.5 9.5 461.5 11.5 SPT N-Value Moisture (%)Groundwater Log Depth Depth and Comments Core Recovery (%) RQD (%) 0 50 100 Elev.Backfill/ Installations/(ft) Sample Number and Location Soil / Rock Description 2231110 1 2 3 4 5 6 7 8 9 10 11 1 2 3 4 5 6 7 8 9 10 11 BORING LOG: BH-2Project No.: Surface Elevation: Date of Boring: November 20, 2023 Rosboro Project Springfield, Oregon BH-2 Page 1 of 1 473.0 feet (Approx.) Professional Geotechnical Services Foundation Engineering, Inc. 43 9 73 43 9 73 DRAFT Capped withcrushed rock Backfilledwith bentonitechips Groundwaterencounteredduring drilling SS-3-1 SH-3-2 SS-3-3 SS-3-4 SS-3-5 SS-3-6 ASPHALTIC CONCRETE (±4 inches). Dense sandy GRAVEL (GP); grey, moist, ±2-inch minussubrounded to rounded gravel, (base rock). Stiff silty CLAY (CH); brown to dark brown andiron-stained, moist, medium to high plasticity, (WillametteSilt). Field vanes on SH-3-2: Su= 0.84 tsf at ±5 feet andSu= 0.46 tsf at ±7.5 feet. Some fine sand below ±7 feet. Sandy below ±11 feet. Dense to very dense sandy GRAVEL, trace silt (GW);wet, fine to coarse sand, fine to coarse subrounded torounded gravel, (alluvium). BOTTOM OF BORING 472.7 0.3 471.0 2.0 460.5 12.5 451.5 21.5 SPT N-Value Moisture (%)Groundwater Log Depth Depth and Comments Core Recovery (%) RQD (%) 0 50 100 Elev.Backfill/ Installations/(ft) Sample Number and Location Soil / Rock Description 2231110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 BORING LOG: BH-3Project No.: Surface Elevation: Date of Boring: November 20, 2023 Rosboro Project Springfield, Oregon BH-3 Page 1 of 1 473.0 feet (Approx.) Professional Geotechnical Services Foundation Engineering, Inc. 13 15 13 69 33 13 15 13 69 33 DRAFT Capped withcrushed rock Backfilledwith bentonitechips Groundwater encountered during drilling SS-4-1 SS-4-2 SS-4-3 SS-4-4 SS-4-5 Dense CRUSHED ROCK (GP); grey, moist, ±2-inchminus angular rock, (fill). ±1-inch minus crushed rock below ±1.5 feet. SILT, some debris (ML); grey, moist, low to mediumplasticity, debris consists of brick and concrete fragments,(fill). Very stiff silty CLAY (CH); dark brown, moist, medium tohigh plasticity, (Willamette Silt). Iron-stained from ±5 to 7 feet. Stiff and dark grey below ±7 feet. Very dense sandy GRAVEL, trace silt (GP); grey-brown,wet, fine to coarse sand, fine to coarse subrounded torounded gravel, (alluvium). BOTTOM OF BORING 474.0 2.0 472.5 3.5 461.5 14.5 459.6 16.4 SPT N-Value Moisture (%)Groundwater Log Depth Depth and Comments Core Recovery (%) RQD (%) 0 50 100 Elev.Backfill/ Installations/(ft) Sample Number and Location Soil / Rock Description 2231110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 BORING LOG: BH-4Project No.: Surface Elevation: Date of Boring: November 20, 2023 Rosboro Project Springfield, Oregon BH-4 Page 1 of 1 476.0 feet (Approx.) Professional Geotechnical Services Foundation Engineering, Inc. 30 19 10 9 96/11" 30 19 10 9 96/11" DRAFT Capped withcrushedgravel Backfilledwith bentonitechips Groundwater encountered during drilling SS-5-1 SS-5-2 SS-5-3 SS-5-4 SS-5-5 Dense silty CRUSHED GRAVEL (GM); grey-brown,moist, low plasticity silt, ±2-inch minus, (fill). Blue-grey with scattered wood fibers below ±2 feet. Stiff silty CLAY (CH); dark brown, moist, medium to highplasticity, (Willamette Silt). Iron-stained below ±6 feet. Medium stiff to stiff below ±7 feet. Very dense sandy GRAVEL, trace silt (GW); grey, wet,fine to coarse sand, fine to coarse subrounded to roundedgravel, (alluvium). BOTTOM OF BORING 471.0 4.0 461.5 13.5 458.5 16.5 SPT N-Value Moisture (%)Groundwater Log Depth Depth and Comments Core Recovery (%) RQD (%) 0 50 100 Elev.Backfill/ Installations/(ft) Sample Number and Location Soil / Rock Description 2231110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 BORING LOG: BH-5Project No.: Surface Elevation: Date of Boring: November 20, 2023 Rosboro Project Springfield, Oregon BH-5 Page 1 of 1 475.0 feet (Approx.) Professional Geotechnical Services Foundation Engineering, Inc. 31 12 9 6 91/11½" 31 12 9 6 91/11½" ldh (1-10-2024) DRAFT Capped withAC coldpatch Backfilledwith bentonitechips Groundwaterencounteredduring drilling SH-7-1 SS-7-2 SS-7-3 SS-7-4 SS-7-5 SS-7-6 ASPHALTIC CONCRETE (±5 inches). Very dense CRUSHED ROCK (GP); grey, wet, ±3-inchminus angular rock, (base rock). Medium stiff silty CLAY, scattered organics (CH);grey-brown, moist, medium to high plasticity, organicsconsist of wood fragments, (fill).Field vanes on SH-7-1: Su= 0.46 tsf at ±2.5 feet andSu= 0.30 tsf at ±4 feet. Medium stiff silty CLAY (CH); brown and iron-stained,moist to wet, medium to high plasticity, (Willamette Silt). Soft, some fine sand, and grey mottling below±10 feet. Dense to very dense sandy GRAVEL, trace silt (GW);grey, wet, fine to coarse sand, fine to coarse roundedgravel, (alluvium). BOTTOM OF BORING 474.6 0.4 473.0 2.0 471.0 4.0 464.0 11.0 453.5 21.5 SPT N-Value Moisture (%)Groundwater Log Depth Depth and Comments Core Recovery (%) RQD (%) 0 50 100 Elev.Backfill/ Installations/(ft) Sample Number and Location Soil / Rock Description 2231110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 BORING LOG: BH-7Project No.: Surface Elevation: Date of Boring: December 4, 2023 Rosboro Project Springfield, Oregon BH-7 Page 1 of 1 475.0 feet (Approx.) Professional Geotechnical Services Foundation Engineering, Inc. 5 8 20 50/3" 43 5 8 20 50/3" 43 DRAFT Capped withAC coldpatch Backfilledwith bentonitechips Groundwater encountered during drilling SS-8-1 SH-8-2 SS-8-3 SS-8-4 SS-8-5 SS-8-6 ASPHALTIC CONCRETE (±8 inches). Very dense sandy GRAVEL (GP); grey, wet, fine tocoarse sand, fine to coarse subrounded to roundedgravel, (base rock). Soft to medium stiff silty CLAY, trace sand (CH); grey,wet, medium to high plasticity, fine sand, (fill). Medium stiff silty CLAY (CH); brown, moist, medium tohigh plasticity, (Willamette Silt). Field vanes on SH-8-2: Su= 0.72 tsf at ±5 feet andSu= 0.82 tsf at ±7.5 feet. Stiff and iron-stained below ±7.5 feet. Mottled grey and wet below ±10 feet. Very dense sandy GRAVEL, trace silt (GW); grey, wet,fine to coarse sand, fine to coarse rounded gravel,(alluvium). BOTTOM OF BORING 475.3 0.7 474.0 2.0 473.0 3.0 462.0 14.0 454.5 21.5 SPT N-Value Moisture (%)Groundwater Log Depth Depth and Comments Core Recovery (%) RQD (%) 0 50 100 Elev.Backfill/ Installations/(ft) Sample Number and Location Soil / Rock Description 2231110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 BORING LOG: BH-8Project No.: Surface Elevation: Date of Boring: December 4, 2023 Rosboro Project Springfield, Oregon BH-8 Page 1 of 1 476.0 feet (Approx.) Professional Geotechnical Services Foundation Engineering, Inc. 7 11 14 60 54 7 11 14 60 54 DRAFT Appendix C Laboratory Test Results Foundation Engineering, Inc. Professional Geotechnical Services DRAFT Foundation Engineering, Inc. Rosboro Project Project No.: 2231110 Table 1C. Laboratory Test Results Sample Number Sample Depth (feet) Moisture Content (%) LL PL PI USCS Classification SS-1-1 2.5 – 4.0 38.0 86 32 54 CH SS-5-2 5.0 – 6.5 31.8 81 30 51 CH SS-8-1 2.5 – 4.0 37.2 77 31 46 CH Table 2C. Expansion Index of Soils (ASTM D4829) Sample Number Sample Depth (ft) Initial Initial Reading (mm) Final Reading (mm) Final Moisture Content (%) Expansion Index Height (in) Moisture Content (%) Dry Density (pcf) Degree of Saturation (%) S-1-1 2.5 –4.0 0.999 19.2 94.4 52.0 0.0000 0.04865 39.6 49 Table 3C. Field Vane Undrained Shear Strength (SU) Test Results Sample Number Test Depth (feet) Undrained Shear Strength (tsf) SH-1-3 7.5 0.74 SH-3-2 5.0 0.84 7.5 0.46 SH-7-1 2.5 0.46 4.0 0.30 SH-8-2 5.0 0.72 7.5 0.82 DRAFT Rosboro Mill Expansion | KPFF Consulting Engineers PRELIMINARY STORMWATER REPORT Appendix 7 O&M Report 1201 Oak Street, Suite 100, Eugene, OR 97401 541-684-4902| www.kpff.com