Full Text
Letter of Approval – GRAD 25-01 – Heartwood Assisted Living Page 1 of 2 March 4, 2025 Norm Scheg, Civil Engineer AAI Engineering 4875 SW Griffith Dr. Ste 100 Beaverton, OR 97005 RE: Approval of Grading Permit GRAD 25-01 “Heartwood Assisted Living” for 2355 N Boones Ferry Rd., (Tax Lot 051W07BA00900) Dear Mr. Scheg: Staff approves the Grading Permit, subject to the conditions of approval outlined in this letter. Summary of Review: This site is subject to the development standards of the Woodburn Development Ordinance (WDO). The applicant is requesting to perform grading work in preparation for an additional 46- unit assisted living facility with site landscaping and parking improvements. Pursuant to WDO 4.01.02, the Director shall render all Type I land use decisions. The Director’s decision is the final decision of the City on a Type I application and cannot be appealed by any party through the City land use appeals process. Planning Conditions of Approval: 1. Conformance with Approved Plans: All site work shall be in substantial conformance with the approved grading plans. 2. DEQ: All development activity shall be in accordance with the approved Department of Environmental Quality (DEQ) 1200-C permit. The applicant shall provide to the City any modifications to the DEQ permit. 3. Other agencies: The applicant, not the City, is responsible for obtaining permits from Marion County, US Army Corps of Engineers (USACE), Oregon Department of State Lands (DSL), Oregon Department of Transportation (ODOT), and other agencies which might require approval or permit. ---PAGE BREAK--- Letter of Approval – GRAD 25-01 – Heartwood Assisted Living Page 2 of 2 4. ROW: All work within City rights-of-way or easements within City jurisdiction shall require plan approval and permit issuance from the Public Works Department. Public Works Conditions of Approval: 5. The applicant shall comply with the submitted grading and erosion control plans, including measures to keep the ROW clean, to protect existing catch basins around the work area, and maintain dust control measures. All catch basins around the work area shall be clean of debris and soils at all times. 6. The applicant shall continuously maintain adequate protection of all work from damage and protect the public and private property of others from injury or loss arising in connection with the work. 7. The applicant shall comply with City of Woodburn Planning Department requirements through Woodburn Development Ordinance (WDO) 5.01.04 Grading Permit. 8. Prior to starting work, contact the identified DEQ site inspector for inspection of erosion control within the public ROW. 9. The applicant shall leave ROW in clean condition, free from litter and debris, at the end of each workday, or more frequently if directed by the site inspector. 10. Sidewalk and street closures are not allowed under this permit. 11. Prior to starting work, silt fencing shall be installed around the entire perimeter of the work area. Applicant shall comply with all requirements and conditions set on their 1200C permit. Final decision approved by designee: Heidi Hinshaw March 4, 2025 Associate Planner Attachment: Approved Grading & Erosion Control Plans cc: Mark Miller, Architect- Ankrom Moisan, [EMAIL REDACTED] Terri Waldroff, Manager- WMC Holding LLC, [EMAIL REDACTED] Erin Holsonback , Landscape Architect-Otten & Associates, [EMAIL REDACTED] Terri Waldroff, Landowner, [EMAIL REDACTED] Chris Kerr, Community Development Director, [EMAIL REDACTED] Dago Garcia, PE, City Engineer, [EMAIL REDACTED] Melissa Gitt, Building Official, [EMAIL REDACTED] ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- Department of Environmental Quality Water Quality Tina Kotek, Governor November 12, 2024 Terri Waldroff Benicia Senior Living 1800 Blankenship Rd Ste 475 West Linn, Oregon 97068 Re: 1200-C National Pollutant Discharge Elimination System (NPDES) Registration Legal Name of Permit Registrant: Benicia Senior Living, LLC Facility Name: Heartwood Assisted Living Facility Permit/PLC Number: NGEN12C-ORR10J376 Project Location: 2355 N Boones Ferry Rd, Woodburn, Oregon 97071 Marion County Dear Terri Waldroff: The Oregon Department of Environmental Quality (DEQ) has reviewed your application and approved your registration for coverage under the NPDES 1200-C construction stormwater permit. As the registrant, you are legally responsible for compliance with all permit conditions; please follow this link, 1200-C Permit, for a copy of the permit. Registrant Obligations • Comply with all permit conditions. DEQ strongly recommends that you read the permit. • Fully implement your Erosion and Sediment Control Plan (ESCP). You may need to modify site control measures as site conditions change. • Ensure that all appropriate contractors hired by you to implement the permit on your behalf have a copy of the ESCP and the permit. Keep a list of all contractors working on your site along with their contact information. • Notify DEQ of significant projects changes, including ESCP revisions, inspectors, or project ownership changes electronically through YDO. • Perform & document visual monitoring according to Schedule B of the permit by a certified erosion and sediment control person. • Terminate coverage at the end of the project electronically through YDO. You will be charged an annual registration fee until registration is terminated. The permit does not authorize excavation or fill in state waterways, including wetlands, and does not replace the requirement for receiving authorization to do this type of work under Section 404 of the Clean Water Act. If the authorized activity involves earthmoving in a known or suspected wetland condition you must contact the Department of State Lands at [PHONE REDACTED] if you are west of the Cascades, or 541-388- 6112 if you are east of the Cascades, and request a wetland determination prior to earth moving. The construction stormwater general permit, technical assistance manuals and other information is also available on DEQ Stormwater Program’s website. Sincerely, DEQ Stormwater Permitting Program ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS 7 C4.0 PLAN SECTION SECTION 10 C4.0 ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS UNPAVED AREAS PAVED AREAS SECTION WYE PLUGGED CROSS TEE BEND PLUGGED CROSS TEE PLUG OR CAP BEARING AREA OF THRUST BLOCK IN SQUARE FOOT PLAN SIDE SECTION ELEVATION PLAN METER SIDE CUSTOMER SIDE PLAN SECTION SECTION A PLAN SHEAR GATE DETAILS 1 2 3 ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 GRADING PERMIT HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2355 N BOONES FERRY RD, WOODBURN, OR 97071 10/22/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- SITE © 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- ’ ’ ’ PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- PROPOSED TWO STORY ASSISTED LIVING FACILITY PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- PROPOSED TWO STORY ASSISTED LIVING FACILITY PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- · · · · SIDE VIEW FRONT VIEW PLAN VIEW DETAIL FABRIC POST POCKET TURNED ENDS GEOTEXTILE END CONNECTIONS FLOW FLOW PLAN SECTION LAYOUT AT CATCH BASIN LAYOUT AT AREA DRAIN STEEP SLOPE BAG DETAIL ® PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 1200C PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 07/29/2024 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 ---PAGE BREAK--- Woodburn ALF STORMWATER REPORT & CALCULATIONS Woodburn, Oregon 97071 Revised November 20, 2023 Revised March 27, 2022 Revised February 11, 2022 January 13, 2022 PROJECT NUMBER: A21152.10 Christopher Thornton, PE AAI Engineering 4875 S.W. Griffith Drive Suite 100 Beaverton, Oregon PH [PHONE REDACTED] FX [PHONE REDACTED] EMAIL: [EMAIL REDACTED] ---PAGE BREAK--- Woodburn ALF Table of Contents I. Project Summary 1 II. Stormwater Design 1 III. Calculations 1 IV. Operations and Maintenance 2 V. Engineering Conclusion 2 Appendices Appendix A Existing Conditions Appendix B Site Plan Appendix C Storm Plan and Details Appendix D Stormwater Calculation Appendix E Operations and Maintenance Form Appendix F Geotechnical Report ---PAGE BREAK--- Woodburn ALF 1 I. Project Summary This report has been prepared to outline the existing and proposed on-site stormwater conditions for the Woodburn ALF Housing project. The report is based off topographic survey and field observation. The project is located at 2325 N Boones Ferry Rd in Woodburn, Oregon. The total pre-developed site is approximately 1.59 acres. The site currently consists of an open field and vegetation, and is relatively flat. See Appendix A – Existing Conditions The primary purpose of this project is to develop the site for a 2-story memory care facility with driveways, pedestrian connection and associated utilities. The site improvements will consist of 0.91 acres of impervious area. In addition to the site improvements, stormwater management will be provided, including conveyance and flow control. See Appendix B – Site Plan and Appendix C – Storm Plan and Details. II. Stormwater Design The proposed stormwater facilities are designed to capture all runoff from the proposed site improvements. No runoff from adjacent properties is anticipated to be captured by the proposed facilities. In addition, all site impervious runoff will be completely managed on site and will not drain onto adjacent properties. The runoff from the roofs will be directed into downspouts, runoff from AC will sheet flow into sumped and trapped catchbasins. A geotechnical report was conducted and very little infiltration was available on site. Per Table 7-1 of the City of Woodburn Stormwater Drainage Master Plan, a 10 acre site is allowed to have a maximum runoff from the 25 year design storm of 0.713csf and needs to provided a minimum of 18,883CF of storage. Our site is only 1.59 acres so by proportionally, our site may have a max outflow on the 25-year design storm of 0.113cfa and must provide 3002.4CF of storage. We are proposing the use of an underground chamber storage facility that will provide 3,024CF of storage and with the use of a flow control manhole we will limit the 25-year flows to 0.11. Both of these values meet those required by Table 7-1. See Appendix E – HydroCAD Report and Storm Calculations and Appendix F Geotech Report III. Calculations See Appendix D – Stormwater Calculations ---PAGE BREAK--- Woodburn ALF 2 IV. Operations and Maintenance See Appendix E – Operations and Maintenance Form for O&M requirements. V. Engineering Conclusion Based on the requirements of the City of Woodburn Management Manual, the proposed site facilities will be adequately designed to manage the proposed development. ---PAGE BREAK--- Woodburn ALF A Appendix A Existing Conditions ---PAGE BREAK--- Woodburn ALF Table of Contents I. Project Summary 1 II. Stormwater Design 1 III. Calculations 1 IV. Operations and Maintenance 2 V. Engineering Conclusion 2 Appendices Appendix A Existing Conditions Appendix B Site Plan Appendix C Storm Plan and Details Appendix D Stormwater Calculation Appendix E Operations and Maintenance Form Appendix F Geotechnical Report ---PAGE BREAK--- Woodburn ALF 1 I. Project Summary This report has been prepared to outline the existing and proposed on-site stormwater conditions for the Woodburn ALF Housing project. The report is based off topographic survey and field observation. The project is located at 2325 N Boones Ferry Rd in Woodburn, Oregon. The total pre-developed site is approximately 1.59 acres. The site currently consists of an open field and vegetation, and is relatively flat. See Appendix A – Existing Conditions The primary purpose of this project is to develop the site for a 2-story memory care facility with driveways, pedestrian connection and associated utilities. The site improvements will consist of 0.91 acres of impervious area. In addition to the site improvements, stormwater management will be provided, including conveyance and flow control. See Appendix B – Site Plan and Appendix C – Storm Plan and Details. II. Stormwater Design The proposed stormwater facilities are designed to capture all runoff from the proposed site improvements. No runoff from adjacent properties is anticipated to be captured by the proposed facilities. In addition, all site impervious runoff will be completely managed on site and will not drain onto adjacent properties. The runoff from the roofs will be directed into downspouts, runoff from AC will sheet flow into sumped and trapped catchbasins. A geotechnical report was conducted and very little infiltration was available on site. Per Table 7-1 of the City of Woodburn Stormwater Drainage Master Plan, a 10 acre site is allowed to have a maximum runoff from the 25 year design storm of 0.713csf and needs to provided a minimum of 18,883CF of storage. Our site is only 1.59 acres so by proportionally, our site may have a max outflow on the 25-year design storm of 0.113cfa and must provide 3002.4CF of storage. We are proposing the use of an underground chamber storage facility that will provide 3,024CF of storage and with the use of a flow control manhole we will limit the 25-year flows to 0.11. Both of these values meet those required by Table 7-1. See Appendix E – HydroCAD Report and Storm Calculations and Appendix F Geotech Report III. Calculations See Appendix D – Stormwater Calculations ---PAGE BREAK--- Woodburn ALF 2 IV. Operations and Maintenance See Appendix E – Operations and Maintenance Form for O&M requirements. V. Engineering Conclusion Based on the requirements of the City of Woodburn Management Manual, the proposed site facilities will be adequately designed to manage the proposed development. ---PAGE BREAK--- Woodburn ALF A Appendix A Existing Conditions ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- Woodburn ALF B Appendix B Site Plan ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- Woodburn ALF C Appendix C Storm Plan and Details ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS UNPAVED AREAS PAVED AREAS SECTION WYE PLUGGED CROSS TEE BEND PLUGGED CROSS TEE PLUG OR CAP BEARING AREA OF THRUST BLOCK IN SQUARE FOOT PLAN SIDE SECTION ELEVATION PLAN METER SIDE CUSTOMER SIDE PLAN SECTION SECTION A PLAN SHEAR GATE DETAILS 1 2 3 ---PAGE BREAK--- PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- Woodburn ALF D Appendix D Stormwater Calculation ---PAGE BREAK--- ---PAGE BREAK--- 1S Post Developed 1P SC-310 Chambers Routing Diagram for 21152 Woodburn ALF Prepared by AAI Engineering, Printed 11/20/2023 HydroCAD® 10.00-26 s/n 01638 © 2020 HydroCAD Software Solutions LLC Subcat Reach Pond Link ---PAGE BREAK--- Type IA 24-hr 25yr Rainfall=2.45" 21152 Woodburn ALF Printed 11/20/2023 Prepared by AAI Engineering Page 2 HydroCAD® 10.00-26 s/n 01638 © 2020 HydroCAD Software Solutions LLC Time span=0.00-50.00 hrs, dt=0.05 hrs, 1001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=69,261 sf 57.19% Impervious Runoff Depth=1.34" Subcatchment 1S: Post Developed Tc=5.0 min CN=88 Runoff=0.52 cfs 0.177 af Peak Elev=1.33' Storage=2,068 cf Inflow=0.52 cfs 0.177 af Pond 1P: SC-310 Chambers Outflow=0.11 cfs 0.177 af Total Runoff Area = 1.590 ac Runoff Volume = 0.177 af Average Runoff Depth = 1.34" 42.81% Pervious = 0.681 ac 57.19% Impervious = 0.909 ac ---PAGE BREAK--- Type IA 24-hr 25yr Rainfall=2.45" 21152 Woodburn ALF Printed 11/20/2023 Prepared by AAI Engineering Page 3 HydroCAD® 10.00-26 s/n 01638 © 2020 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: Post Developed Runoff = 0.52 cfs @ 7.95 hrs, Volume= 0.177 af, Depth= 1.34" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-50.00 hrs, dt= 0.05 hrs Type IA 24-hr 25yr Rainfall=2.45" Area (sf) CN Description * 39,611 98 Paved parking, Concrete, Roof 29,650 74 >75% Grass cover, Good, HSG C 69,261 88 Weighted Average 29,650 42.81% Pervious Area 39,611 57.19% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Subcatchment 1S: Post Developed Runoff Hydrograph Time (hours) 50 48 46 44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Flow (cfs) 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type IA 24-hr 25yr Rainfall=2.45" Runoff Area=69,261 sf Runoff Volume=0.177 af Runoff Depth=1.34" Tc=5.0 min CN=88 0.52 cfs ---PAGE BREAK--- Type IA 24-hr 25yr Rainfall=2.45" 21152 Woodburn ALF Printed 11/20/2023 Prepared by AAI Engineering Page 4 HydroCAD® 10.00-26 s/n 01638 © 2020 HydroCAD Software Solutions LLC Summary for Pond 1P: SC-310 Chambers Inflow Area = 1.590 ac, 57.19% Impervious, Inflow Depth = 1.34" for 25yr event Inflow = 0.52 cfs @ 7.95 hrs, Volume= 0.177 af Outflow = 0.11 cfs @ 12.63 hrs, Volume= 0.177 af, Atten= 79%, Lag= 281.0 min Primary = 0.11 cfs @ 12.63 hrs, Volume= 0.177 af Routing by Stor-Ind method, Time Span= 0.00-50.00 hrs, dt= 0.05 hrs Peak Elev= 1.33' @ 12.63 hrs Surf.Area= 2,400 sf Storage= 2,068 cf Plug-Flow detention time= 277.2 min calculated for 0.177 af (100% of inflow) Center-of-Mass det. time= 277.8 min ( 1,063.4 - 785.6 ) Volume Invert Avail.Storage Storage Description #1 0.00' 1,712 cf Custom Stage Data (Prismatic) Listed below (Recalc) 5,592 cf Overall - 1,312 cf Embedded = 4,280 cf x 40.0% Voids #2 0.00' 1,312 cf ADS_StormTech SC-310 +Cap x 89 Inside #1 Effective Size= 28.9"W x 16.0"H 2.07 sf x 7.12'L = 14.7 cf Overall Size= 34.0"W x 16.0"H x 7.56'L with 0.44' Overlap 89 Chambers in 10 Rows 3,024 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 0.00 2,400 0 0 2.33 2,400 5,592 5,592 Device Routing Invert Outlet Devices #1 Primary 0.00' 1.9" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.11 cfs @ 12.63 hrs HW=1.33' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.11 cfs @ 5.56 fps) ---PAGE BREAK--- Type IA 24-hr 25yr Rainfall=2.45" 21152 Woodburn ALF Printed 11/20/2023 Prepared by AAI Engineering Page 5 HydroCAD® 10.00-26 s/n 01638 © 2020 HydroCAD Software Solutions LLC Pond 1P: SC-310 Chambers Inflow Primary Hydrograph Time (hours) 50 48 46 44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Flow (cfs) 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=1.590 ac Peak Elev=1.33' Storage=2,068 cf 0.52 cfs 0.11 cfs ---PAGE BREAK--- 25yr KKA Date: NWS Upstream Structure Structure Area Area Runoff Coeff. Equiv. Area Total Drainage Area Time of Concent. Or Flow Time Total Time of Concent. Average Rainfall Intensity Design Discharge IE (in) IE (out) Pipe Length Min. Invert Slope Pipe Size Capacity Flowing Full Velocity Flowing Full Flow Time (cA) (cA) sqft acres acres acres min min in/hr cfs ft ft ft % in cfs fps min CB-08 109 2180 0.050 0.90 0.045 0.045 5.0 5.0 3.40 0.153 180.15 178.62 47.00 3.3% 6 1.01 5.17 0.2 AD-01 109 1043 0.024 0.90 0.022 0.022 5.0 5.0 3.40 0.073 178.73 178.62 23.00 0.5% 6 0.39 1.98 0.2 [PHONE REDACTED] 0.074 0.90 0.067 0.067 5.0 5.0 3.40 0.226 178.62 178.48 28.00 0.5% 6 0.40 2.02 0.2 CB-06 110 2384 0.055 0.90 0.049 0.049 5.0 5.0 3.40 0.167 180.69 178.48 6.00 36.8% 6 3.41 17.38 0.0 [PHONE REDACTED] 0.129 0.90 0.116 0.116 5.0 5.0 3.40 0.394 178.48 178.31 34.00 0.5% 6 0.40 2.02 0.3 AD-02 111 2672 0.061 0.90 0.055 0.055 5.0 5.0 3.40 0.188 178.50 178.31 22.00 0.9% 6 0.52 2.66 0.1 [PHONE REDACTED] 0.190 0.90 0.171 0.171 5.0 5.0 3.40 0.582 178.31 177.98 67.00 0.5% 8 0.85 2.43 0.5 CB-05 113 3666 0.084 0.90 0.076 0.076 5.0 5.0 3.40 0.258 181.06 177.98 34.00 9.1% 6 1.69 8.62 0.1 113 115 11945 0.274 0.90 0.247 0.247 5.0 5.0 3.40 0.839 178.98 177.69 56.00 2.3% 8 1.84 5.27 0.2 0.000 0.90 0.000 0.000 5.0 5.0 3.40 0.000 AD-05 131 1827 0.042 0.90 0.038 0.038 5.0 5.0 3.40 0.128 179.00 178.25 50.00 1.5% 6 0.69 3.51 0.2 AD-04 131 3130 0.072 0.90 0.065 0.065 5.0 5.0 3.40 0.220 178.50 178.25 12.00 2.1% 6 0.81 4.13 0.0 [PHONE REDACTED] 0.114 0.90 0.102 0.102 5.0 5.0 3.40 0.348 178.25 178.05 41.00 0.5% 6 0.39 2.00 0.3 AD-03 128 2147 0.049 0.90 0.044 0.044 5.0 5.0 3.40 0.151 179.00 178.05 9.23 10.3% 6 1.80 9.19 0.0 [PHONE REDACTED] 0.163 0.90 0.147 0.147 5.0 5.0 3.40 0.499 178.05 177.69 73.00 0.5% 8 0.85 2.44 0.5 115 116 19049 0.437 0.90 0.394 0.394 5.0 5.0 3.40 1.338 177.69 177.63 11.00 0.5% 10 1.62 2.97 0.1 0.000 0.90 0.000 0.000 5.0 5.0 3.40 0.000 CB-01 136 1749 0.040 0.90 0.036 0.036 5.0 5.0 3.40 0.123 178.67 177.82 41.00 2.1% 6 0.81 4.12 0.2 CB-02 136 9918 0.228 0.90 0.205 0.205 5.0 5.0 3.40 0.697 178.01 177.82 5.25 3.6% 8 2.30 6.60 0.0 136 116 11667 0.268 0.90 0.241 0.241 5.0 5.0 3.40 0.820 177.82 177.63 40.00 0.5% 8 0.83 2.39 0.3 116 117 30716 0.705 0.90 0.635 0.635 5.0 5.0 3.40 2.158 177.63 177.59 7.00 0.6% 12 2.70 3.44 0.0 CB-03 144 0.000 0.90 0.000 0.000 5.0 5.0 3.40 0.000 CB-03 144 772 0.018 0.90 0.016 0.016 5.0 5.0 3.40 0.054 180.00 177.78 25.00 8.9% 6 1.68 8.53 0.0 CB-04 144 958 0.022 0.90 0.020 0.020 5.0 5.0 3.40 0.067 180.71 177.78 36.00 8.1% 6 1.60 8.17 0.1 [PHONE REDACTED] 0.040 0.90 0.036 0.036 5.0 5.0 3.40 0.122 177.78 177.59 39.00 0.5% 6 0.39 2.00 0.3 11/20/2023 Designed By: Checked By: Project Name: Woodburn ALF Project A21152.10 Design Frequency: Page 1 ---PAGE BREAK--- 25yr KKA Date: NWS Upstream Structure Structure Area Area Runoff Coeff. Equiv. Area Total Drainage Area Time of Concent. Or Flow Time Total Time of Concent. Average Rainfall Intensity Design Discharge IE (in) IE (out) Pipe Length Min. Invert Slope Pipe Size Capacity Flowing Full Velocity Flowing Full Flow Time (cA) (cA) sqft acres acres acres min min in/hr cfs ft ft ft % in cfs fps min 11/20/2023 Designed By: Checked By: Project Name: Woodburn ALF Project A21152.10 Design Frequency: FALSE 0.90 0.000 0.036 5.0 5.0 3.40 0.122 117 WQMH-01 32446 0.745 0.90 0.670 0.670 5.0 5.0 3.40 2.279 177.59 177.57 4.73 0.4% 12 2.32 2.96 0.0 WQMH-01 DET 32446 0.745 0.90 0.670 0.670 5.0 5.0 3.40 2.279 177.57 177.54 6.87 0.4% 12 2.36 3.00 0.0 DET FCMH-01 32446 0.745 0.90 0.670 0.670 5.0 5.0 3.40 2.279 177.54 177.50 7.00 0.6% 12 2.70 3.44 0.0 FCMH-01 154 32446 0.745 0.90 0.670 0.670 5.0 5.0 3.40 2.279 177.50 177.00 121.00 0.4% 12 2.30 2.92 0.7 Page 2 ---PAGE BREAK--- PROPOSED TWO STORY ASSISTED LIVING FACILITY PROJECT NUMBER © ANKROM MOISAN ARCHITECTS, INC. 38 NORTHWEST DAVIS, SUITE 300 PORTLAND, OR 97209 [PHONE REDACTED] 1505 5TH AVE, SUITE 300 SEATTLE, WA 98101 [PHONE REDACTED] 1014 HOWARD STREET SAN FRANCISCO, CA 94103 [PHONE REDACTED] DATE SHEET NUMBER SHEET NUMBER 203170 PERMIT SET HEARTWOOD ASSISTED LIVING FACILITY WMC HOLDING COMPANY. LLC 2325 N BOONES FERRY RD, WOODBURN, OR 97071 11/21/2023 REVISION DATE REASON FOR ISSUE 4875 SW Griffith Drive I Suite 100 I Beaverton, OR I 97005 [PHONE REDACTED] tel. I [PHONE REDACTED] fax I www.aaieng.com Project No. A21152.10 B 11/21/23 PLAN CHECK COMMENTS ---PAGE BREAK--- Woodburn ALF E Appendix E Operations and Maintenance Form ---PAGE BREAK--- Isolator® Row O&M Manual ---PAGE BREAK--- 2 Looking down the Isolator Row from the manhole opening, woven geotextile Fabric is shown between the chamber and stone base. StormTech Isolator Row with Overflow Spillway (not to scale) The Isolator® Row Introduction An important component of any Stormwater Pollution Prevention Plan is inspection and maintenance. The StormTech Isolator Row is a technique to inexpensively enhance Total Suspended Solids (TSS) and Total Phosphorus (TP) removal with easy access for inspection and maintenance. The Isolator Row The Isolator Row is a row of StormTech chambers, either SC-160, SC- 310, SC-310-3, SC-740, DC-780, MC-3500 or MC-7200 models, that is surrounded with filter fabric and connected to a closely located manhole for easy access. The fabric-wrapped chambers provide for sediment settling and filtration as stormwater rises in the Isolator Row and passes through the filter fabric. The open bottom chambers and perforated sidewalls (SC-310, SC- 310-3 and SC-740 models) allow stormwater to flow both vertically and horizontally out of the chambers. Sediments are captured in the Isolator Row protecting the adjacent stone and chambers storage areas from sediment accumulation. ADS geotextile fabric is placed between the stone and the Isolator Row chambers. The woven geotextile provides a media for stormwater filtration, a durable surface for maintenance, prevents scour of the underlying stone and remains intact during high pressure jetting. A non-woven fabric is placed over the chambers to provide a filter media for flows passing through the chamber’s sidewall. The non-woven fabric is not required over the SC-160, DC-780, MC-3500 or MC-7200 models as these chambers do not have perforated side walls. The Isolator Row is designed to capture the “first flush” runoff and offers the versatility to be sized on a volume basis or a flow-rate basis. An upstream manhole provides access to the Isolator Row and includes a high/low concept such that stormwater flow rates or volumes that exceed the capacity of the Isolator Row bypass through a manifold to the other chambers. This is achieved with an elevated bypass manifold or a high-flow weir. This creates a differential between the Isolator Row row of chambers and the manifold to the rest of the system, thus allowing for settlement time in the Isolator Row. After Stormwater flows through the Isolator Row and into the rest of the chamber system it is either exfiltrated into the soils below or passed at a controlled rate through an outlet manifold and outlet control structure. The Isolator Row may be part of a treatment train system. The treatment train design and pretreatment device selection by the design engineer is often driven by regulatory requirements. Whether pretreatment is used or not, StormTech recommend using the Isolator Row to minimize maintenance requirements and maintenance costs. Note: See the StormTech Design Manual for detailed information on designing inlets for a StormTech system, including the Isolator Row. ECCENTRIC HEADER MANHOLE WITH OVERFLOW WEIR STORMTECH ISOLATOR ROW OPTIONAL PRE-TREATMENT OPTIONAL ACCESS STORMTECH CHAMBERS ---PAGE BREAK--- 3 Inspection The frequency of inspection and maintenance varies by location. A routine inspection schedule needs to be established for each individual location based upon site specific variables. The type of land use (i.e. industrial, commercial, residential), anticipated pollutant load, percent imperviousness, climate, etc. all play a critical role in determining the actual frequency of inspection and maintenance practices. At a minimum, StormTech recommends annual inspections. Initially, the Isolator Row should be inspected every 6 months for the first year of operation. For subsequent years, the inspection should be adjusted based upon previous observation of sediment deposition. The Isolator Row incorporates a combination of standard manhole(s) and strategically located inspection ports (as needed). The inspection ports allow for easy access to the system from the surface, eliminating the need to perform a confined space entry for inspection purposes. If upon visual inspection it is found that sediment has accumulated, a stadia rod should be inserted to determine the depth of sediment. When the average depth of sediment exceeds 3 inches throughout the length of the Isolator Row, clean-out should be performed. Maintenance The Isolator Row was designed to reduce the cost of periodic maintenance. By “isolating” sediments to just one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage bed. If inspection indicates the potential need for maintenance, access is provided via a manhole(s) located on the end(s) of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a confined space entries. Maintenance is accomplished with the JetVac process. The JetVac process utilizes a high pressure water nozzle to propel itself down the Isolator Row while scouring and suspending sediments. As the nozzle is retrieved, the captured pollutants are flushed back into the manhole for vacuuming. Most sewer and pipe maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle will improve maintenance efficiency. Fixed nozzles designed for culverts or large diameter pipe cleaning are preferable. Rear facing jets with an effective spread of at least 45” are best. JetVac reels can vary in length. For ease of maintenance, ADS recommends Isolator Row up to 200" (61 The JetVac process shall only be performed on StormTech Isolator Rows that have AASHTO class 1 woven geotextile (as specified by StormTech) over their angular base stone. Isolator Row Inspection/Maintenance StormTech Isolator Row (not to scale) Note: Non-woven fabric is only required over the inlet pipe connection into the end cap for SC-160LP, DC-780, MC- 3500 and MC-7200 chamber models and is not required over the entire Isolator Row. ---PAGE BREAK--- Isolator Row Step By Step Maintenance Procedures Step 1 Inspect Isolator Row for sediment. A) Inspection ports (if present) i. Remove lid from floor box frame ii. Remove cap from inspection riser iii. Using a flashlight and stadia rod,measure depth of sediment and record results on maintenance log. iv. If sediment is at or above 3 inch depth, proceed to Step 2. If not, proceed to Step 3. B) All Isolator Row i. Remove cover from manhole at upstream end of Isolator Row ii. Using a flashlight, inspect down Isolator Row through outlet pipe 1. Mirrors on poles or cameras may be used to avoid a confined space entry 2. Follow OSHA regulations for confined space entry if entering manhole iii. If sediment is at or above the lower row of sidewall holes (approximately 3 inches), proceed to Step 2. If not, proceed to Step 3. Step 2 Clean out Isolator Row using the JetVac process. A) A fixed floor cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable B) Apply multiple passes of JetVac until backflush water is clean C) Vacuum manhole sump as required Step 3 Replace all caps, lids and covers, record observations and actions. Step 4 Inspect & clean catch basins and manholes upstream of the StormTech system. ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com The ADS logo and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. Stormtech® and the Isolator® Row are registered trademarks of StormTech, Inc. © 2022 Advanced Drainage Systems, Inc. #11011 2/22 CS Sample Maintenance Log Date Stadia Rod Readings Sedi- ment Depth Observations/Actions Inspector Fixed point to chamber bottom Fixed point to top of sediment 3/15/11 6.3 ft none New installation. Fixed point is CI frame at grade DJM 9/24/11 6.2 0.1 ft Some grit felt SM 6/20/13 5.8 0.5 ft Mucky feel, debris visible in manhole and in Isolator Row, maintenance due NV 7/7/13 6.3 ft 0 System jetted and vacuumed DJM adspipe.com [PHONE REDACTED] ---PAGE BREAK--- Woodburn ALF F Appendix F Geotechnical Report ---PAGE BREAK--- Real-World Geotechnical Solutions Investigation • Design • Construction Support 14835 SW 72nd Avenue Tel (503) 598-8445 Portland, Oregon 97224 Fax (503) 941-9281 December 9, 2021 Project No. 21-5923 Ed Ziebart WCM Holding Company, LLC. 1900 Hines Street SE, Suite 190 Salem, Oregon 97302 Phone: (503)363-4677 Via email: [EMAIL REDACTED] Subject: GEOTECHNICAL ENGINEERING REPORT WOODBURN II ASSISTED LIVING FACILITY 2355 N BOONES FERRY ROAD WOODBURN, OREGON This report presents the results of a geotechnical engineering study conducted by GeoPacific Engineering, Inc. (GeoPacific) for the above-referenced project. The purpose of our investigation was to evaluate subsurface conditions at the site and to provide geotechnical recommendations for site development. This geotechnical study was performed in accordance with GeoPacific Proposal No. P-7879, dated October 21, 2021, and your subsequent authorization of our proposal and General Conditions for Geotechnical Services. SITE DESCRIPTION AND PROPOSED DEVELOPMENT The subject site is located on the west side of N. Boones Ferry Road and the south side of Country Club Road in the City of Woodburn, Marion County, Oregon (Figure The property is approximately 1.6 acres in size and topography is flat to very gently sloping. Vegetation consists primarily of short grasses. The site is currently unimproved. It is our understanding that the proposed development will consist of a two story assisted living facility approximately 40,200 square feet in size, parking areas, stormwater disposal facility, and associated underground utilities (Figure A grading plan has not been provided for our review; however, we anticipate maximum cuts and fills will be on the order of about 4 feet or less due to the relatively flat topography. ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 2 REGIONAL GEOLOGIC SETTING Regionally, the subject site lies within the Willamette Valley/Puget Sound lowland, a broad structural depression situated between the Coast Range on the west and the Cascade Range on the east. A series of discontinuous faults subdivide the Willamette Valley into a mosaic of fault- bounded, structural blocks (Yeats et al., 1996). Uplifted structural blocks form bedrock highlands, while down-warped structural blocks form sedimentary basins. The subject site is underlain by the Quaternary age (last 1.6 million years) Willamette Formation, a catastrophic flood deposit associated with repeated glacial outburst flooding of the Willamette Valley (Madin, 1990; Gannett and Caldwell, 1998). The last of these outburst floods occurred about 10,000 years ago These deposits typically consist of horizontally layered, micaceous, silt to coarse sand forming poorly-defined to distinct beds less than 3 feet thick. Underlying the Willamette Formation is basalt bedrock belonging to the Columbia River Basalt Formation (Gannett and Caldwell, 1998; O’Connor et al., 2001). The Miocene aged (about 14.5 to 16.5 million years ago) Columbia River Basalts are a thick sequence of lava flows which form the basement of the Willamette Valley (Beeson el al., 1989). The basalts are composed of dense, finely rock that is commonly fractured along blocky and columnar vertical joints. Individual basalt flow units typically range from 25 to 125 feet thick and interflow zones are typically vesicular, scoriaceous, brecciated, and sometimes include sedimentary rocks. REGIONAL SEISMIC SETTING At least three potential source zones capable of generating damaging earthquakes are thought to exist in the region. These include the Portland Hills Fault Zone, the Gales Creek-Newberg-Mt. Angel Structural Zone, and the Cascadia Subduction Zone, as discussed below. Portland Hills Fault Zone The Portland Hills Fault Zone is a series of NW-trending faults that include the central Portland Hills Fault, the western Oatfield Fault, and the eastern East Bank Fault. These faults occur in a northwest-trending zone that varies in width between 3.5 and 5.0 miles. The combined three faults vertically displace the Columbia River Basalt by 1,130 feet and appear to control thickness changes in late Pleistocene (approx. 780,000 years) sediment (Madin, 1990). The Portland Hills Fault occurs along the Willamette River at the base of the Portland Hills and is approximately 21.4 miles northeast of the site. The East Bank Fault is oriented roughly parallel to the Portland Hills Fault, on the east bank of the Willamette River, and is located approximately 27.2 miles northeast of the site. The Oatfield Fault occurs along the western side of the Portland Hills and is approximately 20 miles northeast of the site. The Oatfield Fault is considered to be potentially seismogenic (Wong, et al., 2000). Madin and Mabey (1996) indicate the Portland Hills Fault Zone has experienced Late Quaternary (last 780,000 years) fault movement; however, movement has not been detected in the last 20,000 years. The accuracy of the fault mapping is stated to be within 500 meters (Wong, et al., 2000). No historical seismicity is correlated with the mapped portion of the Portland Hills Fault Zone, but in 1991 a M3.5 earthquake occurred on a NW-trending shear plane located 1.3 miles east of the fault (Yelin, 1992). Although there is no definitive evidence of recent activity, the Portland Hills Fault Zone is assumed to be potentially active (Geomatrix Consultants, 1995). ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 3 Gales Creek-Newberg-Mt. Angel Structural Zone The Gales Creek-Newberg-Mt. Angel Structural Zone is a 50-mile-long zone of discontinuous, NW- trending faults that lies about 2.1 miles south of the subject site. These faults are recognized in the subsurface by vertical separation of the Columbia River Basalt and offset seismic reflectors in the overlying basin sediment (Yeats et al., 1996; Werner et al., 1992). A geologic reconnaissance and photogeologic analysis study conducted for the Scoggins Dam site in the Tualatin Basin revealed no evidence of deformed geomorphic surfaces along the structural zone (Unruh et al., 1994). No seismicity has been recorded on the Gales Creek Fault or Newberg Fault; however, these faults are considered to be potentially active because they may connect with the seismically active Mount Angel Fault and the rupture plane of the 1993 M5.6 Scotts Mills earthquake (Werner et al., 1992; Geomatrix Consultants, 1995). Cascadia Subduction Zone The Cascadia Subduction Zone is a 680-mile-long zone of active tectonic convergence where oceanic crust of the Juan de Fuca Plate is subducting beneath the North American continent at a rate of 4 cm per year (Goldfinger et al., 1996). A growing body of geologic evidence suggests that prehistoric subduction zone earthquakes have occurred (Atwater, 1992; Carver, 1992; Peterson et al., 1993; Geomatrix Consultants, 1995). This evidence includes: buried tidal marshes recording episodic, sudden subsidence along the coast of northern California, Oregon, and Washington, burial of subsided tidal marshes by tsunami wave deposits, paleoliquefaction features, and geodetic uplift patterns on the Oregon coast. Radiocarbon dates on buried tidal marshes indicate a recurrence interval for major subduction zone earthquakes of 250 to 650 years with the last event occurring 300 years ago (Atwater, 1992; Carver, 1992; Peterson et al., 1993; Geomatrix Consultants, 1995). The inferred seismogenic portion of the plate interface lies approximately 50 miles west of the Portland Basin at depths of between 20 and 40 kilometers below the surface. FIELD EXPLORATION Our site-specific exploration for this report was conducted on November 29, 2021. Four exploratory borings were drilled to depths of 11.5 to 21.5 feet and one exploratory test pit was excavated with a medium sized trackhoe to a depth of 20 inches at the approximate locations shown on Figure 2. It should be noted that exploration locations were located in the field by pacing or taping distances from apparent property corners and other site features shown on the plans provided. As such, the locations of the explorations should be considered approximate. The boreholes were drilled using a trailer-mounted drill rig and solid stem auger methods. At each boring location, SPT (Standard Penetration Test) sampling was performed in general accordance with ASTM D1586 using a 2-inch outside diameter split-spoon sampler and a 140-pound hammer equipped with a rope and cathead mechanism. During the test, a sample is obtained by driving the sampler 18 inches into the soil with the hammer free-falling 30 inches. The number of blows for each 6 inches of penetration is recorded. The Standard Penetration Resistance (“N-value”) of the soil is calculated as the number of blows required for the final 12 inches of penetration. If 50 or more blows are recorded within a single 6-inch interval, the test is terminated, and the blow count is recorded as 50 blows for the number of inches driven. This resistance, or N-value, provides a measure of the relative density of granular soils and the relative consistency of cohesive soils. At the completion of the borings, the holes were backfilled with bentonite. ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 4 Explorations were conducted under the full-time observation of a GeoPacific Engineering Geologist. Soil samples obtained from the explorations were classified in the field and representative portions were placed in relatively air-tight plastic bags. These soil samples were then returned to the laboratory for further examination and laboratory testing. Pertinent information including soil sample depths, stratigraphy, soil engineering characteristics, and groundwater occurrence was recorded. Soils were classified in general accordance with the Unified Soil Classification System (USCS). Summary exploration logs are attached. The stratigraphic contacts shown on the individual logs represent the approximate boundaries between soil types. The actual transitions may be more gradual. The soil and groundwater conditions depicted are only for the specific dates and locations reported, and therefore, are not necessarily representative of other locations and times. SUBSURFACE CONDITIONS The following discussion is a summary of subsurface conditions encountered in our explorations. For more detailed information regarding subsurface conditions at specific exploration locations, refer to the attached exploration logs. Also, please note that subsurface conditions can vary between exploration locations, as discussed in the Uncertainty and Limitations section at the conclusion of this report. Soils On-site soils consist of topsoil horizon, undocumented fill, and Willamette Formation materials as described below. Undocumented Fill: Undocumented fill was encountered in test pit TP-1. The fill generally consisted of medium dense, silty gravel (GM) with trace fine roots. Other areas or thicker areas of fill may be present in areas beyond the exploration locations, especially in the vicinity of the existing driveway. Topsoil Horizon: The ground surface in borings B-1 through B-4 was directly underlain by a topsoil horizon. The topsoil horizon generally consisting of moderately organic, brown silt (ML-OL) that contained fine roots throughout. The topsoil horizon was approximately 12 inches thick in borings. Approximately 6 inches of topsoil had developed on the undocumented fill in test pit TP-1. Willamette Formation: Underlying the topsoil horizon in boring B-1 through B-4 and the fill in test pit TP-1 were soils belonging to the Willamette Formation. These soils typically consisted of light brown silt (ML) with trace sand that displayed subtle to strong orange and gray mottling. The silt with trace sand typically had a medium stiff to stiff consistency that extended to a depth of 5 to 7.5 feet. The silt with trace sand was underlain by interbedded silty sand (SM) and sandy silt (ML) that had a medium stiff to stiff consistency or a loose to medium dense relative density. Below a depth of 7.5 to 15 feet, the interbedded sandy silt and silty sand transitioned to stiff to very stiff and medium dense to dense. Soils belonging to the Willamette Formation extended beyond the maximum depth of exploration in explorations (11.5 to 21.5 feet). Groundwater On November 29, 2021, static groundwater was encountered in borings at depths of 7.5 to 11 feet. Based on our review of available well logs, groundwater is commonly encountered at depths ranging from less than 10 to 40 feet below the ground surface within the site vicinity (Oregon Water ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 5 Resources Department, 2021). Experience has shown that temporary perched storm-related groundwater conditions often occur within the surface soils over fine-grained native deposits such as those beneath the site, particularly during the wet season. It is anticipated that groundwater conditions will vary depending on the season, local subsurface conditions, changes in site utilization, and other factors. INFILTRATION TESTING Soil infiltration testing was performed using the pushed pipe infiltration method in test pit TP-1 at a depth of 20 inches. The soil was pre-saturated for a period of over 2 hours. The water level was measured to the nearest tenth of an inch every fifteen minutes to half hour with reference to the ground surface. Table 1 presents the results of our falling head infiltration tests. Table 1. Summary of Infiltration Test Results Test Pit Depth (inches) Soil Type Ultimate Infiltration Rate (in/hr) Hydraulic Head Range (inches) TP-1 20 Silt (ML) 0 10-11 CONCLUSIONS AND RECOMMENDATIONS Results of this study indicate the proposed development is geotechnically feasible, provided the recommendations of this report are incorporated into the design and construction phases of the project. In our opinion, the primary geotechnical constraint to the project include: 1. The presence of low permeability soils. The results of our infiltration testing indicate the site is not suitable for stormwater disposal. 2. The presence of undocumented fill. Approximately 1 foot of fill was encountered in test pit TP-1. Other areas of fill may be present outside our exploration locations. 3. Shallow groundwater conditions. Static groundwater was encountered in explorations at depths of 7.5 to 11 feet. These shallow groundwater conditions may make deep excavations and utility trenching difficult in the winter and spring months. Adequate shoring should be maintained. Recommendations are presented below for site preparation and undocumented fill removal; engineered fill; excavating conditions and utility trench backfill; erosion control considerations; wet weather earthwork; pavement design; structural foundations; permanent below-grade walls; concrete slabs-on-grade; and seismic design. Site Preparation and Undocumented Fill Removal The proposed structure areas should be cleared of debris. If encountered, undocumented fill within the proposed building footprints, beneath pavements or other settlement-sensitive improvements, should be completely removed and replaced with engineered fill. Approximately 1 ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 6 foot of undocumented fill was encountered in test pit TP-1. Other or deeper areas of fill may exist elsewhere on the property. Following removal of surficial debris and any encountered undocumented fill, the exposed subgrade should be ripped or tilled to a depth of 12 inches, moisture conditioned, and compacted in-place prior to the placement of engineered fill or crushed aggregate base for pavement. Exposed subgrade soils should be evaluated by GeoPacific. For large areas, this evaluation is normally performed by proof-rolling the exposed subgrade with a fully loaded scraper or dump truck. For smaller areas where access is restricted, the subgrade should be evaluated by probing the soil with a steel probe. Soft/loose soils identified during subgrade preparation should be compacted to a firm and unyielding condition or over-excavated and replaced with engineered fill, as described below. The depth of overexcavation, if required, should be evaluated by GeoPacific at the time of construction. Following removal, portions of the undocumented fill soils that do not contain organic or other deleterious material may be re-used as engineered fill during dry-weather construction. GeoPacific should be on-site during fill removal and recompaction efforts, to verify the suitability of soils for recompaction and to monitor the fill placement and compaction efforts. During wet weather, the predominantly silt undocumented fill soils will likely not be usable as engineered fill due to their moisture-sensitive nature. Engineered Fill In general, we anticipate that soils from planned cuts and utility trench excavations will be suitable for use as engineered fill provided they are adequately moisture conditioned prior to compacting. Imported fill material should be reviewed by GeoPacific prior to being imported to the site. Oversize material greater than 6 inches in size should not be used within 3 feet of foundation footings, and material greater than 12 inches in diameter should not be used in engineered fill. Engineered fill should be compacted in horizontal lifts not exceeding 8 inches using standard compaction equipment. We recommend that engineered fill be compacted to at least 95 percent of the maximum dry density determined by ASTM D698 (Standard Proctor) or equivalent. On-site soils may be wet or dry of optimum; therefore, we anticipate that moisture conditioning of native soil will be necessary for compaction operations. Proper test frequency and earthwork documentation usually requires daily observation and testing during stripping, rough grading, and placement of engineered fill. Field density testing should generally conform to ASTM D2922 and D3017, or D1556. Engineered fill should be periodically observed and tested by the project geotechnical engineer or his representative. Typically, one density test is performed for at least every 2 vertical feet of fill placed or every 500 cubic yards, whichever requires more testing. Because testing is performed on an on-call basis, we recommend that the earthwork contractor be held contractually responsible for test scheduling and frequency. Excavating Conditions and Utility Trench Backfill We anticipate that on-site soils can be excavated using conventional heavy equipment to a depth of 21.5 feet. Static groundwater was encountered at depths of 7.5 to 11 feet which may make deep excavations or utility trenching difficult in the winter and spring months. Adequate shoring should be maintained. Maintenance of safe working conditions, including temporary excavation stability, is the responsibility of the contractor. Actual slope inclinations at the time of construction should be determined based on safety requirements and actual soil and groundwater conditions. ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 7 All temporary cuts in excess of 4 feet in height should be sloped in accordance with U.S. Occupational Safety and Health Administration (OSHA) regulations (29 CFR Part 1926), or be shored. The existing native near surface soils classify as Type B Soil and temporary excavation side slope inclinations as steep as 1H:1V may be assumed for planning purposes. This cut slope inclination is applicable to excavations above the water table only. Shallow, perched groundwater may be encountered during the wet weather season and should be anticipated in excavations and utility trenches. Vibrations created by traffic and construction equipment may cause some caving and raveling of excavation walls. In such an event, lateral support for the excavation walls should be provided by the contractor to prevent loss of ground support and possible distress to existing or previously constructed structural improvements. PVC pipe should be installed in accordance with the procedures specified in ASTM D2321. We recommend that structural trench backfill be compacted to at least 95% of the maximum dry density obtained by Standard Proctor (ASTM D698) or equivalent. Initial backfill lift thicknesses for a ¾”-0 crushed aggregate base may need to be as great as 4 feet to reduce the risk of flattening underlying flexible pipe. Subsequent lift thickness should not exceed 1 foot. If imported granular fill material is used, then the lifts for large vibrating plate-compaction equipment (e.g. hoe compactor attachments) may be up to 2 feet, provided that proper compaction is being achieved and each lift is tested. Use of large vibrating compaction equipment should be carefully monitored near existing structures and improvements due to the potential for vibration-induced damage. Adequate density testing should be performed during construction to verify that the recommended relative compaction is achieved. Typically, at least one density test is taken for every 4 vertical feet of backfill on each 200-lineal-foot section of trench. Erosion Control Considerations During our field exploration program, we did not observe soil types that would be considered highly susceptible to erosion. In our opinion, the primary concern regarding erosion potential will occur during construction, in areas that have been stripped of vegetation. Erosion at the site during construction can be minimized by implementing the project erosion control plan, which should include judicious use of silt fences, straw wattles, and fiber rolls. If used, these erosion control devices should be in place and remain in place throughout site preparation and construction. Erosion and sedimentation of exposed soils can also be minimized by quickly re-vegetating exposed areas of soil, and by staging construction such that large areas of the project site are not denuded and exposed at the same time. Areas of exposed soil requiring immediate and/or temporary protection against exposure should be covered with either mulch or erosion control netting/blankets. Areas of exposed soil requiring permanent stabilization should be seeded with an approved grass seed mixture, or hydroseeded with an approved seed-mulch-fertilizer mixture. Wet Weather Earthwork Soils underlying the site are likely to be moisture sensitive and may be difficult to handle or traverse with construction equipment during periods of wet weather. Earthwork is typically most economical when performed under dry weather conditions. Earthwork performed during the wet- weather season will probably require expensive measures such as cement treatment or imported granular material to compact fill to the recommended engineering specifications. If earthwork is to be performed or fill is to be placed in wet weather or under wet conditions when soil moisture ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 8 content is difficult to control, the following recommendations should be incorporated into the contract specifications. Earthwork should be performed in small areas to minimize exposure to wet weather. Excavation or the removal of unsuitable soils should be followed by the placement and compaction of clean engineered fill. The size and type of construction equipment used may have to be limited to prevent soil disturbance. Under some circumstances, it may be necessary to excavate soils with a backhoe to minimize subgrade disturbance caused by equipment traffic; The ground surface within the construction area should be graded to promote run-off of surface water and to prevent the ponding of water; Material used as engineered fill should consist of clean, granular soil containing less than 5 percent fines. The fines should be non-plastic. Alternatively, cement treatment of on-site soils may be performed to facilitate wet weather placement; The ground surface within the construction area should be sealed by a smooth drum vibratory roller, or equivalent, and under no circumstances should be left uncompacted and exposed to moisture. Soils which become too wet for compaction should be removed and replaced with clean granular materials; Excavation and placement of fill should be observed by the geotechnical engineer to verify that all unsuitable materials are removed and suitable compaction and site drainage is achieved; and Geotextile silt fences, straw wattles, and fiber rolls should be strategically located to control erosion. If cement or lime treatment is used to facilitate wet weather construction, GeoPacific should be contacted to provide additional recommendations and field monitoring. Pavement Design For design purposes, we used an estimated resilient modulus of 9,000 for compacted native soil. Table 2 presents our recommended minimum pavement section for dry weather construction for the proposed parking lot and access driveway. Table 2. Recommended Minimum Dry-Weather Pavement Section Material Layer Parking Lots and Access Driveways Compaction Standard Asphaltic Concrete (AC) 4 in. 92% of Rice Density AASHTO T-209 Crushed Aggregate Base ¾”-0 (leveling course) 2 in. 95% of Modified Proctor AASHTO T-180 Crushed Aggregate Base 1½”-0 8 in. 95% of Modified Proctor AASHTO T-180 Subgrade 12 in. 95% of Standard Proctor AASHTO T-99 or equivalent Subgrade in pavement areas should be ripped or tilled to a minimum depth of 12 inches, moisture conditioned, and recompacted in-place to at least 95 percent of ASTM D698 (Standard Proctor) or equivalent. Any pockets of organic debris or loose fill encountered during subgrade preparation ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 9 should be removed and replaced with engineered fill (see Site Preparation Section). In order to verify subgrade strength, we recommend proof-rolling directly on subgrade with a loaded dump truck during dry weather and on top of base course in wet weather. Soft areas that pump, rut, or weave should be stabilized prior to paving. The moisture sensitive subgrade soils make the site a difficult wet weather construction project. General recommendations for wet weather construction are provided in the following report section. However, the subgrade and construction plan should be evaluated at the time of construction so that condition-specific recommendations can be provided. During placement of pavement section materials, density testing should be performed to verify compliance with project specifications. Generally, one subgrade, one base course, and one asphalt compaction test is performed for every 100 to 200 linear feet of paving. Structural Foundations Based on our understanding of the proposed project and the results of our exploration program, and assuming our recommendations for site preparation are followed, native deposits and/or engineered fill soils should be encountered at or near the foundation level of the proposed structures. These soils are generally medium stiff to stiff and should provide adequate support of the structural loads. Shallow, conventional isolated or continuous spread footings may be used to support the proposed structures, provided they are founded on competent native soils, or compacted engineered fill placed directly upon the competent native soils. We recommend a maximum allowable bearing pressure of 1,500 pounds per square foot (psf). The recommended maximum allowable bearing pressures may be increased by 1/3 for short term transient conditions such as wind and seismic loading. All footings should be founded at least 18 inches below the lowest adjacent finished grade. Minimum footing widths should be determined by the project engineer/architect in accordance with applicable design codes. Assuming construction is accomplished as recommended herein, and for the foundation loads anticipated, we estimate total settlement of spread foundations of less than about 1 inch and differential settlement between two adjacent load-bearing components supported on competent soil of less than about ½ inch. We anticipate that the majority of the estimated settlement will occur during construction, as loads are applied. Wind, earthquakes, and unbalanced earth loads will subject the proposed structure to lateral forces. Lateral forces on a structure will be resisted by a combination of sliding resistance of its base or footing on the underlying soil and passive earth pressure against the buried portions of the structure. For use in design, a coefficient of friction of 0.42 may be assumed along the interface between the base of the footing and subgrade soils. Passive earth pressure for buried portions of structures may be calculated using an equivalent fluid weight of 320 pounds per cubic foot (pcf), assuming footings are cast against dense, natural soils or engineered fill. The recommended coefficient of friction and passive earth pressure values do not include a safety factor. The upper 12 inches of soil should be neglected in passive pressure computations unless it is protected by pavement or slabs on grade. Footing excavations should be trimmed neat and the bottom of the excavation should be carefully prepared. Loose, wet or otherwise softened soil should be removed from the footing excavation prior to placing reinforcing steel bars. ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 10 The above foundation recommendations are for dry weather conditions. Due to the high moisture sensitivity of on-site soils, construction during wet weather may require overexcavation of footings and backfill with compacted, crushed aggregate. GeoPacific should observe foundation excavations prior to placing formwork and reinforcing steel, to verify that adequate bearing soils have been reached. Permanent Below-Grade Walls Lateral earth pressures against below-grade retaining walls will depend upon the inclination of any adjacent slopes, type of backfill, degree of wall restraint, method of backfill placement, degree of backfill compaction, drainage provisions, and magnitude and location of any adjacent surcharge loads. At-rest soil pressure is exerted on a retaining wall when it is restrained against rotation. In contrast, active soil pressure will be exerted on a wall if its top is allowed to rotate or yield a distance of roughly 0.001 times its height or greater. If the subject retaining walls will be free to rotate at the top, they should be designed for an active earth pressure equivalent to that generated by a fluid weighing 35 pcf for level backfill against the wall. For restrained wall, an at-rest equivalent fluid pressure of 55 pcf should be used in design, again assuming level backfill against the wall. These values assume that the recommended drainage provisions are incorporated, and hydrostatic pressures are not allowed to develop against the wall. During a seismic event, lateral earth pressures acting on below-grade structural walls will increase by an incremental amount that corresponds to the earthquake loading. Based on the Mononobe- Okabe equation and peak horizontal accelerations appropriate for the site location, seismic loading should be modeled using the active or at-rest earth pressures recommended above, plus an incremental rectangular-shaped seismic load of magnitude 6.5H, where H is the total height of the wall. We assume relatively level ground surface below the base of the walls. As such, we recommend passive earth pressure of 390 pcf for use in design, assuming wall footings are cast against competent native soils or engineered fill. If the ground surface slopes down and away from the base of any of the walls, a lower passive earth pressure should be used and GeoPacific should be contacted for additional recommendations. A coefficient of friction of 0.42 may be assumed along the interface between the base of the wall footing and subgrade soils. The recommended coefficient of friction and passive earth pressure values do not include a safety factor, and an appropriate safety factor should be included in design. The upper 12 inches of soil should be neglected in passive pressure computations unless it is protected by pavement or slabs on grade. The above recommendations for lateral earth pressures assume that the backfill behind the subsurface walls will consist of properly compacted structural fill, and no adjacent surcharge loading. If the walls will be subjected to the influence of surcharge loading within a horizontal distance equal to or less than the height of the wall, the walls should be designed for the additional horizontal pressure. For uniform surcharge pressures, a uniformly distributed lateral pressure of 0.3 times the surcharge pressure should be added. Traffic surcharges may be estimated using an additional vertical load of 250 psf (2 feet of additional fill), in accordance with local practice. The recommended equivalent fluid densities assume a free-draining condition behind the walls so that hydrostatic pressures do not build-up. This can be accomplished by placing a 12- to 18-inch ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 11 wide zone of sand and gravel containing less than 5 percent fines against the walls. A 3-inch minimum diameter perforated, plastic drain pipe should be installed at the base of the walls and connected to a suitable discharge point to remove water in this zone of sand and gravel. The drain pipe should be wrapped in filter fabric (Mirafi 140N or other as approved by the geotechnical engineer) to minimize clogging. GeoPacific should be contacted during construction to verify subgrade strength in wall keyway excavations, to verify that backslope soils are in accordance with our assumptions, and to take density tests on the wall backfill materials. Structures should be located a horizontal distance of at least 1.5H away from the back of the retaining wall, where H is the total height of the wall. GeoPacific should be contacted for additional foundation recommendations where structures are located closer than 1.5H to the top of any wall. Concrete Slabs-on-Grade Preparation of areas beneath concrete slab-on-grade floors should be performed as recommended in the Site Preparation and Undocumented Fill Removal section. Care should be taken during excavation for foundations and floor slabs, to avoid disturbing subgrade soils. If subgrade soils have been adversely impacted by wet weather or otherwise disturbed, the surficial soils should be scarified to a minimum depth of 8 inches, moisture conditioned to within about 3 percent of optimum moisture content, and compacted to engineered fill specifications. Alternatively, disturbed soils may be removed and the removal zone backfilled with additional crushed rock. For evaluation of the concrete slab-on-grade floors using the beam on elastic foundation method, a modulus of subgrade reaction of 150 kcf (87 pci) should be assumed for the medium stiff native silt soils anticipated at subgrade depth. This value assumes the concrete slab system is designed and constructed as recommended herein, with a minimum thickness of crushed rock of 8 inches beneath the slab. Interior slab-on-grade floors should be provided with an adequate moisture break. The capillary break material should consist of ODOT open graded aggregate per ODOT Standard Specifications 02630-2. The minimum recommended thickness of capillary break materials on re-compacted soil subgrade is 8 inches. The total thickness of crushed aggregate will be dependent on the subgrade conditions at the time of construction, and should be verified visually by proof-rolling. Under-slab aggregate should be compacted to at least 90% of its maximum dry density as determined by ASTM D1557 or equivalent. In areas where moisture will be detrimental to floor coverings or equipment inside the proposed structure, appropriate vapor barrier and damp-proofing measures should be implemented. A commonly applied vapor barrier system consists of a 10-mil polyethylene vapor barrier placed directly over the capillary break material. Other damp/vapor barrier systems may also be feasible. Appropriate design professionals should be consulted regarding vapor barrier and damp proofing systems, ventilation, building material selection and mold prevention issues, which are outside GeoPacific’s area of expertise. Seismic Design The Oregon Department of Geology and Mineral Industries (DOGAMI), Oregon HazVu: 2021 Statewide GeoHazards Viewer indicates that the site is in an area where very strong ground shaking is anticipated during an earthquake (DOGAMI HazVu, 2021). Structures should be designed to resist earthquake loading in accordance with the methodology described in the 2018 ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 12 International Building Code (IBC) with applicable Oregon Structural Specialty Code (OSSC) revisions (current 2020). We recommend Site Class D be used for design as defined in ASCE 7, Chapter 20, Table 20.3-1. Design values determined for the site using the ATC (Applied Technology Council) ASCE7-16 Hazards by Location online Tool website are summarized in Table 3. Table 3. Recommended Earthquake Ground Motion Parameters (ATC 2021) Parameter Value Location (Lat, Long), degrees 45.155, -122.859 Mapped Spectral Acceleration Values (MCE): Peak Ground Acceleration PGAM 0.468 g Short Period, Ss 0.84 g 1.0 Sec Period, S1 0.399 g Soil Factors for Site Class D: Fa 1.164 Fv *1.901 SDs = 2/3 x Fa x Ss 0.652 g SD1 = 2/3 x Fv x S1 *0.506 g Seismic Design Category D * The Fv value reported in the above table is a straight-line interpolation of mapped spectral response acceleration at 1-second period, S1 per Table 1613.2.3(2) of OSSC 2019 with the assumption that Exception 2 of ASCE 7-16 Chapter 11.4.8 is met. SD1 is based on the Fv value. The structural engineer should evaluate exception 2 and determine whether or not the exception is met. If Exception 2 is not met, and the long- period site coefficient (Fv) is required for design, GeoPacific Engineering can be consulted to provide a site-specific procedure as per ASCE 7-16, Chapter 21. Soil liquefaction is a phenomenon wherein saturated soil deposits temporarily lose strength and behave as a liquid in response to earthquake shaking. Soil liquefaction is generally limited to loose, granular soils located below the water table. According to the Oregon HazVu: Statewide Geohazards Viewer, the subject site is regionally characterized as having a low risk of soil liquefaction (DOGAMI:HazVu, 2021). Based on our explorations, soils underlying the site are not prone to liquefaction. ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 13 UNCERTAINTIES AND LIMITATIONS We have prepared this report for the owner and their consultants for use in design of this project only. This report should be provided in its entirety to prospective contractors for bidding and estimating purposes; however, the conclusions and interpretations presented in this report should not be construed as a warranty of the subsurface conditions. Experience has shown that soil and groundwater conditions can vary significantly over small distances. Inconsistent conditions can occur between explorations that may not be detected by a geotechnical study. If, during future site operations, subsurface conditions are encountered which vary appreciably from those described herein, GeoPacific should be notified for review of the recommendations of this report, and revision of such if necessary. Sufficient geotechnical monitoring, testing and consultation should be provided during construction to confirm that the conditions encountered are consistent with those indicated by explorations. The checklist attached to this report outlines recommended geotechnical observations and testing for the project. Recommendations for design changes will be provided should conditions revealed during construction differ from those anticipated, and to verify that the geotechnical aspects of construction comply with the contract plans and specifications. Within the limitations of scope, schedule and budget, GeoPacific attempted to execute these services in accordance with generally accepted professional principles and practices in the fields of geotechnical engineering and engineering geology at the time the report was prepared. No warranty, expressed or implied, is made. The scope of our work did not include environmental assessments or evaluations regarding the presence or absence of wetlands or hazardous or toxic substances in the soil, surface water, or groundwater at this site. We appreciate this opportunity to be of service. Sincerely, GEOPACIFIC ENGINEERING, INC. Beth K. Rapp, C.E.G. James D. Imbrie, G.E., C.E.G. Senior Engineering Geologist Principal Geotechnical Engineer Attachments: References Figure 1 – Vicinity Map Figure 2 – Site and Exploration Plan Boring Logs (B-1 – B-4) Test Pit Log (TP-1) Results of Laboratory Testing ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 14 REFERENCES Applied Technology Council (ATC), 2021, Hazards by Location Online Tool, Atwater, B.F., 1992, Geologic evidence for earthquakes during the past 2,000 years along the Copalis River, southern coastal Washington: Journal of Geophysical Research, v. 97, p. 1901-1919. Beeson, M.H., Tolan, T.L., and Anderson, J.L., 1989, The Columbia River Basalt Group in western Oregon; Geologic structures and other factors that controlled flow emplacement patterns: Geological Society of America Special Paper 239, in Volcanism and tectonicism in the Columbia River flood-basalt province published by the Geological Society of America, p. 223-246. Carver, G.A., 1992, Late Cenozoic tectonics of coastal northern California: American Association of Petroleum Geologists-SEPM Field Trip Guidebook, May, 1992. Gannett, M.W. and Caldwell, R.R., 1998, Geologic framework of the Willamette Lowland aquifer system, Oregon and Washington: U.S. Geological Survey Professional Paper 1424-A, 32 8 plates, 1:250,000. Geomatrix Consultants, 1995, Seismic Design Mapping, State of Oregon: unpublished report prepared for Oregon Department of Transportation, Personal Services Contract 11688, January 1995. Goldfinger, Kulm, L.D., Yeats, R.S., Appelgate, B, MacKay, M.E., and Cochrane, G.R., 1996, Active strike-slip faulting and folding of the Cascadia Subduction-Zone plate boundary and forearc in central and northern Oregon: in Assessing earthquake hazards and reducing risk in the Pacific Northwest, v. 1: U.S. Geological Survey Professional Paper 1560, P. 223-256. Madin, I.P., 1990, Earthquake hazard geology maps of the Portland metropolitan area, Oregon: Oregon Department of Geology and Mineral Industries Open-File Report 0-90-2, scale 1:24,000, 22 p. Madin, I.P. and Mabey, M.A., 1996, Earthquake Hazard Maps for Oregon, Oregon: Oregon Department of Geology and Mineral Industries GMS-100. O’Connor, J.E., Sarna-Wojcicki, Wozniak, K.C., Polette, D.J., and Fleck, R.J., 2001, Origin, Extent, and Thickness of Quaternary Geologic Units in the Willamette Valley, Oregon: U.S. Geological Survey, Professional Paper 1620, 51 p, 1 plate, scale 1:250,000. Oregon Department of Geology and Mineral Industries, 2021, Oregon Hazvu: Statewide Geohazards Viewer: Oregon Water Resources Department, 2021, Well Report Query: Peterson, C.D., Darioenzo, M.E., Burns, S.F., and Burris, W.K., 1993, Field trip guide to Cascadia paleoseismic evidence along the northern California coast: evidence of subduction zone seismicity in the central Cascadia margin: Oregon Geology, v. 55, p. 99-144. Unruh, J.R., Wong, I.G., Bott, J.D., Silva, W.J., and Lettis, W.R., 1994, Seismotectonic evaluation: Scoggins Dam, Tualatin Project, Northwest Oregon: unpublished report by William Lettis and Associates and Woodward Clyde Federal Services, Oakland, CA, for U. S. Bureau of Reclamation, Denver CO (in Geomatrix Consultants, 1995). Werner, K.S., Nabelek, Yeats, R.S., Malone, 1992, The Mount Angel fault: implications of seismic- reflection data and the Woodburn, Oregon, earthquake sequence of August, 1990: Oregon Geology, v. 54, p. 112-117. ---PAGE BREAK--- Woodburn II Assisted Living Facility Project No. 21-5923 5923-Woodburn II Assisted Living Facility GR 15 Wong, I. Silva, Bott, Wright, Thomas, Gregor, Li., Mabey, Sojourner, and Wang, 2000, Earthquake Scenario and Probabilistic Ground Shaking Maps for the Portland, Oregon, Metropolitan Area; State of Oregon Department of Geology and Mineral Industries; Interpretative Map Series IMS-16. Yeats, R.S., Graven, E.P., Werner, K.S., Goldfinger, and Popowski, 1996, Tectonics of the Willamette Valley, Oregon: in Assessing earthquake hazards and reducing risk in the Pacific Northwest, v. 1: U.S. Geological Survey Professional Paper 1560, P. 183-222, 5 plates, scale 1:100,000. Yelin, T.S., 1992, An earthquake swarm in the north Portland Hills (Oregon): More speculations on the seismotectonics of the Portland Basin: Geological Society of America, Programs with Abstracts, v. 24, no. 5, p. 92. ---PAGE BREAK--- ---PAGE BREAK--- % ---PAGE BREAK--- 0 .343 &7 ' %7 &1777 % ' &7 1 1 ' ( 1 1 ---PAGE BREAK--- 0 .343 &7 ' %7 &1777 % ' 1 1 ' 1 1 ---PAGE BREAK--- 0 .343 &7 ' %7 &1777 % ' &7 1 1 ' ( 1 ---PAGE BREAK--- 0 .343 &7 ' %7 &1777 % ' 1 1 ? @ ' 1 1 1 ---PAGE BREAK--- # , ) 5$0 133 16333! $ & ( 1 & : 7 ; < = 2 13 11 1& 6 ' ---PAGE BREAK--- Particle Size Distribution Report PERCENT FINER 0 10 20 30 40 50 60 70 80 90 100 PERCENT COARSER 100 90 80 70 60 50 40 30 20 10 0 GRAIN SIZE - mm. 0.001 0.01 0.1 1 10 100 % Coarse % Gravel Fine Coarse Medium % Sand Fine Silt % Fines Clay 0.0 0.0 0.0 0.0 0.4 15.0 84.6 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 #10 #20 #30 #40 #60 #100 #140 #200 TEST RESULTS Opening Percent Spec.* Pass? Size Finer (Percent) (X=Fail) Material Description Atterberg Limits (ASTM D 4318) Classification Coefficients Date Received: Date Tested: Tested By: Checked By: Title: Date Sampled: Location: B-1 Sample Number: S21-317 Depth: 5' Client: Project: Project No: Figure Silt with Sand .75 .5 .375 .25 #4 #10 #20 #40 #100 #200 100.0 100.0 100.0 100.0 100.0 100.0 99.9 99.6 97.1 84.6 26.9 37.0 10.1 ML A-4(9) 0.0971 0.0764 Moisture 33.4% 11/30/2021 SJC 11/29/2021 WCM Holding Company LLC Woodburn Assisted Living Facility Phase 2 21-5923 PL= LL= PI= USCS (D 2487)= AASHTO (M 145)= D90= D85= D60= D50= D30= D15= D10= Cu= Cc= Remarks * (no specification provided) GEOPACIFIC ENGINEERING, INC. ---PAGE BREAK--- Tested By: SJC LIQUID AND PLASTIC LIMITS TEST REPORT PLASTICITY INDEX 0 10 20 30 40 50 60 LIQUID LIMIT 0 10 20 30 40 50 60 70 80 90 100 110 CL-ML CL or OL CH or OH ML or OL MH or OH Dashed line indicates the approximate upper limit boundary for natural soils 4 7 WATER CONTENT 35.6 36 36.4 36.8 37.2 37.6 38 38.4 38.8 39.2 39.6 NUMBER OF BLOWS 5 6 7 8 9 10 20 25 30 40 MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS Project No. Client: Remarks: Project: Location: B-1 Sample Number: S21-317 Depth: 5' GEOPACIFIC ENGINEERING, INC. Figure Silt with Sand 37.0 26.9 10.1 99.6 84.6 ML 21-5923 WCM Holding Company LLC Woodburn Assisted Living Facility Phase 2 ---PAGE BREAK--- Particle Size Distribution Report PERCENT FINER 0 10 20 30 40 50 60 70 80 90 100 PERCENT COARSER 100 90 80 70 60 50 40 30 20 10 0 GRAIN SIZE - mm. 0.001 0.01 0.1 1 10 100 % Coarse % Gravel Fine Coarse Medium % Sand Fine Silt % Fines Clay 0.0 0.0 0.0 0.0 0.2 18.4 81.4 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 #10 #20 #30 #40 #60 #100 #140 #200 TEST RESULTS Opening Percent Spec.* Pass? Size Finer (Percent) (X=Fail) Material Description Atterberg Limits (ASTM D 4318) Classification Coefficients Date Received: Date Tested: Tested By: Checked By: Title: Date Sampled: Location: B-1 Sample Number: S21-318 Depth: 15' Client: Project: Project No: Figure Silt with Sand .75 .5 .375 .25 #4 #10 #20 #40 #100 #200 100.0 100.0 100.0 100.0 100.0 100.0 100.0 99.8 98.2 81.4 25.5 28.4 2.9 ML A-4(1) 0.1017 0.0849 Moisture 33.0% 118/30/2021 SJC 11/29/2021 WCM Holding Company LLC Woodburn Assisted Living Facility Phase 2 21-5923 PL= LL= PI= USCS (D 2487)= AASHTO (M 145)= D90= D85= D60= D50= D30= D15= D10= Cu= Cc= Remarks * (no specification provided) GEOPACIFIC ENGINEERING, INC. ---PAGE BREAK--- Tested By: SJC LIQUID AND PLASTIC LIMITS TEST REPORT PLASTICITY INDEX 0 10 20 30 40 50 60 LIQUID LIMIT 0 10 20 30 40 50 60 70 80 90 100 110 CL-ML CL or OL CH or OH ML or OL MH or OH Dashed line indicates the approximate upper limit boundary for natural soils 4 7 WATER CONTENT 27 27.4 27.8 28.2 28.6 29 29.4 29.8 30.2 30.6 31 NUMBER OF BLOWS 5 6 7 8 9 10 20 25 30 40 MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS Project No. Client: Remarks: Project: Location: B-1 Sample Number: S21-318 Depth: 15' GEOPACIFIC ENGINEERING, INC. Figure Silt with Sand 28.4 25.5 2.9 99.8 81.4 ML 21-5923 WCM Holding Company LLC Woodburn Assisted Living Facility Phase 2