Loading...
HomeMy WebLinkAboutExhibit 14 - Olympic Terrace 2 Phase 2 Plat Alteration review 10-17-2022 Olympic Terrace 2, Phase 2, Plat Alteration 10-17-2022 Page 1 of 6 Date: October 17, 2022 To: David Wayne Johnson, Department of Community Development (DCD) From: Department of Public Works Project: Olympic Terrace 2, Phase 2 Plat Alteration (MLA05-00013, SUB2018-00015, Assessor Parcel # 978802502, -3, -4, Public Works Project #95518015) Subject: Plat Alteration Stormwater Site Plan and Transportation Review and Recommendations Jefferson County Unified Development Code Requirements: The Jefferson County Unified Development Code (UDC), Sections 18.05.060 Dept. of Public Works- Duties and Responsibilities, 18.30.060 Grading and excavation standards, and 18.30.070 Stormwater Management Standards both set standards for erosion and sedimentation control and stormwater management. The code adopts the requirements set forth by the most current version of the Washington State Department of Ecology, Stormwater Management Manual for Western Washington (SWMMWW). The most current version is the 2019 SWMMWW. UDC Section 18.30.080 Roads sets standards for any road in a development. JCPW Findings: At the request of the Department of Community Development (DCD), Jefferson County Public Works (JCPW) reviewed the following plat alteration documents: 1) David Johnson of DCD requested from JCPW an initial review of a Plat Alteration Friday 1/28/2022 consisting of: -Stormwater Site Plan Report by ESM Consulting Engineers of Federal Way, WA signed 11/10/2021 by Trevor Stiff PE, that includes a Soils Report by GeoResources of Fife, WA signed 10/7/2021 by Seth Mattos LEG, Neil Ferguson PE, and Davis Carlsen GIT, with soils logged 9/15/2021. -Road and Utility Construction Plans by ESM of Federal Way, WA signed on 11/12/2021 by Trevor Stiff PE, 31 sheets. -Traffic Memorandum by Jake Traffic Engineering of Seattle, WA signed 10/20/2021 by Mark Jacobs PE, PTOE. Additional information was provided: -Emergency Access Road drawing (sheet EN-07) by ESM Consulting Engineers of Federal Way, dated 12/17/2021, drawn by “CG”. -“Minor Plan Modification” Permit Application from Port Ludlow Associates, signed 5/9/2018 by Cliff O’Brien and Diana Smeland, assigned to MLA18-00041 and SUB 2018-00015. Olympic Terrace 2, Phase 2, Plat Alteration 10-17-2022 Page 2 of 6 -“Wetlands located within the site appeared to have migrated” letter from Port Ludlow Associates, signed by Cliff O’Brien 4/28/2018 -Traffic Impact Assessment signed on 2/24/2005 by Geralyn Reinart PE. -Hearings Examiner Decision signed 6/28/2005 by Irv Berteig The Hearings Examiner Decision required an emergency access roadway, closed to the general public, that follows the Olympic Water and Sewer utility easement that comes off of Teal Lake Road and connects to Mount Constance Way at Lot 10 in the southeast corner of the plat. The Hearings Examiner found that the planned transportation volumes were within design parameters. Hearings Examiner Decision found that improvements to Teal Lake Road were needed as a result of increased traffic from Olympic Terrace 2. Those improvements to Teal Lake Road were subsequently constructed. All pending conditions within the Hearings Examiner Findings, Conclusions, and Decision for SUB05-00003 for Olympic Terrace 2 are still valid for Phase 2 Plat Alteration. New roads and stormwater facilities proposed in Plat Alteration shall not be owned or maintained by County due to lack of sustainable funding for maintenance in County budget. Maintenance shall be by developer or lot owners. JCPW provided review comments 3/16/2022 to DCD with copy to Cliff O’Brien. 2) David Johnson of DCD was provided the following responses to JCPW comments from 3/16/2022 on 5/9/2022 and were copied to JCPW: -Memorandum by ESM Consulting Engineers dated 5/4/2022. -Soil Report Addendum by GeoResources of Fife, WA signed 5/3/2022 by Seth Mattos LEG. -Road and Utility Construction Plans by ESM of Federal Way, WA signed on 5/5/2022 by Trevor Stiff PE, 31 sheets. -Stormwater Site Plan Report by ESM Consulting Engineers of Federal Way, WA signed 5/4/2022 by Trevor Stiff PE, that included a Soils Report by GeoResources of Fife, WA signed 10/7/2021 by Seth Mattos LEG, Neil Ferguson PE, and Davis Carlsen GIT, with soils logged 9/15/2021. JCPW spoke to Trevor Stiff PE of ESM Consulting Engineers, and emailed DCD of that conversation on 5/9/2022. 3) Cliff O’Brien requested a clearing and grading permit application on 5/31/2022, and DCD emailed it to him. 4) Cliff O’Brien forwarded to DCD and JCPW via email on 6/28/2022 the WA State Dept of Ecology Construction Stormwater General Permit he received, permit number WAR311419 for 14 acres of site disturbance. 5) Cliff O’Brien submitted via email 7/1/2022 a clearing and grading permit application. The Stormwater Pollution Prevention Plan specified implementation of the following BMPs: C101, C102, C103, C105, C120, C121, C123, C130, C140, C150, C153, C160, C162, C200, C202, C207, C209, C220, C233, C234, C235, C236, C240, C241. JCPW replied on the same day to DCD that JCPW took no exceptions to the application. 6) Final Plat Alteration documents received for review by JCPW included: Olympic Terrace 2, Phase 2, Plat Alteration 10-17-2022 Page 3 of 6 -a second Memorandum by ESM Consulting Engineers dated 8/22/2022 responding to Jefferson County Public Works comments from 3/16/2022. -Stormwater Site Plan Report by ESM Consulting Engineers of Federal Way, WA signed 8/16/2022 by Trevor Stiff PE, that included a Revised Soils Report by GeoResources of Fife, WA signed 8/17/2022 by Seth Mattos LEG, and Eric Heller PE, LG, with soils logged 7/1/2022. -Road and Utility Construction Plans by ESM of Federal Way, WA signed on 8/16/2022 by Trevor Stiff PE, 31 sheets. With 12.3 acres (8.4 acres along Mt. Wilder Way, and 3.8 acres along McCartney Peak Lane) of land area proposed for disturbance, and 5.5 acres of proposed new hard surfaces (of which 2.7 acres are Pollution Generating Impervious Surfaces), this plat alteration must meet all 9 minimum requirements of the 2019 SWMMWW. The Stormwater Site Plan calls for: A) Lots 16 to 41 of Phase 1 shall have their on-site stormwater managed on each lot as part of their building permit conditions (everything greater than 2,750 square feet of roof area). B) All lots in Phase 2 shall have their stormwater from their roof areas, driveway areas in excess of 500 square feet, and their lawns and landscape greater than 2,580 square feet managed on each lot as part of their building permit conditions. C) Implementation of the following BMPs: T5.13 Post Construction Soil Quality and Depth, soil amendment for all disturbed soils, T7.30 Bioretention Cell (“Rain garden”) with underdrain sized at 14,835 square feet bottom surface area, for Basic Treatment of road surfaces, up to 500 square feet of driveway per lot, and up to 2,580 square feet of lawn/ landscape per lot. Conveyance system employing: C209 Outlet Protection. D) Appendix C of the Plan requires retention of GeoResources for confirmation infiltration testing of all proposed stormwater facilities at the time of construction. 7) JCPW emailed DCD on 9/2/2022 with recommendation to have site’s soils under proposed bioretention cell evaluated between December 1 and April 1 to determine site suitability. JCPW emailed Seth Mattos LEG of GeoResources on 9/8/2022 for clarification on several soil and water characteristics that are documented at the site. -Seth Mattos LEG of GeoResources emailed a reply on 9/9/2022 to request for clarifications. Section V-5.6 Site Suitability Criteria on page 742 of the 2019 SWMMWW states: “When a site investigation reveals that any of the applicable site suitability criteria cannot be met, appropriate mitigation measures must be implemented so that the infiltration BMP will not pose a threat to safety, health, and the environment.” Within GeoResources 9/9/2022 reply to JCPW request for clarifications, Seth Mattos LEG stated “I observed the explorations personally for this submittal and completed the in- situ infiltration testing. The additional explorations within the bioretention facility allowed for very detailed description of the soil and groundwater conditions and the project civil engineer adjusted their design as a result. Given the level of detail associated with the characterization of the soil and groundwater conditions, the revision of the proposed facility, the incorporation of an overflow, and the proposed development’s location adjacent to State forest land, our office feels confident in the proposed Olympic Terrace 2, Phase 2, Plat Alteration 10-17-2022 Page 4 of 6 bioretention facility’s design and the associated on and off-site risk profile.” The licensed professional design team assessed the site and through their collective professional judgement and discretion determined that there are ample design safe guards in place to mitigate imperfections in the soil characteristics that were recognized and documented in the site suitability investigation. JCPW Recommendations: 1. At the time of building permit review, individual Lots 16 to 41 of Phase 1 shall have their on-site stormwater managed on each lot as part of their building permit conditions (everything greater than 2,750 square feet of roof area). 2. At the time of building permit review, all individual lots in Phase 2 shall have stormwater from the following managed on each lot as part of their building permit conditions: all of their roof areas, driveway areas in excess of 500 square feet, and their lawns and landscape greater than 2,580 square feet. 3. Section V-5.6 Site Suitability Criteria on page 742 of the 2019 Stormwater Management Manual for Western WA states: “When a site investigation reveals that any of the applicable site suitability criteria cannot be met, appropriate mitigation measures must be implemented so that the infiltration BMP will not pose a threat to safety, health, and the environment.” Within GeoResources 9/9/2022 reply to JCPW request for clarifications, Seth Mattos LEG stated “I observed the explorations personally for this submittal and completed the in-situ infiltration testing. The additional explorations within the bioretention facility allowed for very detailed description of the soil and groundwater conditions and the project civil engineer adjusted their design as a result. Given the level of detail associated with the characterization of the soil and groundwater conditions, the revision of the proposed facility, the incorporation of an overflow, and the proposed development’s location adjacent to State forest land, our office feels confident in the proposed bioretention facility’s design and the associated on and off-site risk profile.” The licensed professional design team assessed the site and through their collective professional judgement and discretion determined that there are ample design safe guards in place to mitigate imperfections in the soil characteristics that were recognized and documented in the site suitability investigation. As such, the proponent shall construct the stormwater management and transportation facilities as specified in: a) Stormwater Site Plan Report by ESM Consulting Engineers of Federal Way, WA signed 8/16/2022 by Trevor Stiff PE, that included a Revised Soils Report by GeoResources of Fife, WA signed 8/17/2022 by Seth Mattos LEG, and Eric Heller PE, LG, soils logged 7/1/2022. b) Road and Utility Construction Plans by ESM of Federal Way, WA signed on 8/16/2022 by Trevor Stiff PE, 31 sheets. 4. The Olympic Terrace 2, Phase 2 plat alteration shall meet all nine Minimum Requirements of the 2019 Stormwater Management Manual for Western WA through the implementation of the following Best Management Practices: T5.13 Post Construction Soil Quality and Depth, soil amendment for all disturbed soils, T7.30 Bioretention Cell (“Raingarden”) with underdrain sized at 14,835 square feet bottom surface area, for Basic Treatment of road surfaces, up to 500 Olympic Terrace 2, Phase 2, Plat Alteration 10-17-2022 Page 5 of 6 square feet of driveway per lot, and up to 2,580 square feet of lawn/ landscape per lot. Conveyance system employing: C209 Outlet Protection. To meet Minimum Requirement 2, a separate Construction Stormwater Pollution Prevention Plan was issued 7/7/2022 by the Department of Community Development for project clearing and grading under ZON2022- 00022. The Stormwater Pollution Prevention Plan specified implementation of the following BMPs: C101, C102, C103, C105, C120, C121, C123, C130, C140, C150, C153, C160, C162, C200, C202, C207, C209, C220, C233, C234, C235, C236, C240, C241. 5. Sites with greater than 1 acre of disturbance trigger the requirement to have a developer provided Certified Erosion and Sediment Control Lead (CESCL) inspector and site log book, as per Element #12 Manage the Project, of Minimum Requirement #2 Construction Stormwater Pollution Prevention. The CESCL inspector must be identified by the time of start of construction, and must be present on-site or on call at all times. 6. The proponent has acquired from WA State Department of Ecology an NPDES Construction Stormwater General Permit (CSWGP), permit number WAR311419. 7. As per Appendix C of ESM Consulting Engineers’ Stormwater Site Plan report, project proponent shall retain GeoResources or equal to complete confirmation infiltration testing of all proposed stormwater facilities at time of construction, and provide results with professional interpretation to JCPW for acceptance. 8. Plat Alteration shall be bound to the Hearings Examiner Findings, Conclusions, and Decision for SUB05-00003 for Olympic Terrace 2 of 6/28/2005. 9. New roads proposed within Phase 2 (McCartney Peak Lane and extension of Mt. Wilder Way) shall be privately owned and maintained by the developer or lot owners under a recorded road maintenance agreement. 10. All new stormwater management facilities including collection, conveyance and treatment shall be privately owned and maintained by the developer or lot owners under a recorded stormwater maintenance agreement. 11. In accordance with the Jefferson County Unified Development Code, Section 18.30.080 (1) (f): Clearing, grading, and construction of roads, bridges, utilities, and stormwater management facilities shall be inspected by JCPW. In order to enable the department to conduct inspections in a timely manner, the applicant shall notify the department in a timely manner regarding the project construction schedule. Typical Inspections: • Installation of temporary erosion and sediment control measures (Required) • Clearing (and Grading) and road subgrade preparation; • Placing roadway gravel base; • Placing roadway crushed surfacing top course; • Placing improved roadway surface (chip seal or asphalt concrete); • Construction of stormwater management facilities; (Required) • Final plat review. • (Additional inspections may be deemed necessary as project progresses.) 12. After construction is complete and prior to final DCD project approval, the proponent shall submit a letter to the Public Works Department, from the Engineer of Record (EOR), certifying that the stormwater management facilities have been constructed per the approved plans & Olympic Terrace 2, Phase 2, Plat Alteration 10-17-2022 Page 6 of 6 specifications. If the stormwater management facilities were constructed other than shown on the approved plans, the EOR shall submit record drawings showing the changes. It is the responsibility of the proponent to schedule inspections with the EOR, his designee &/or qualified inspection firm(s), approved by the EOR, to provide for said final certification. 13. To meet MR#9 Operation & Maintenance, and ensure that the approved stormwater management facilities are appropriately maintained for the life of the project, prior to final project approval, the proponent shall enter into a Stormwater Management Facility Maintenance Agreement with Jefferson County. The Public Works Department will send a copy of the Agreement to the proponent which has been signed by the Public Works Director. The proponent shall sign the Agreement before a notary, file it with the Jefferson County Auditor, and provide Public Works with a copy of the recorded document. County Auditor 2022 recording fees are $203.50 for the first page and $1 for each additional page. Public Works Department Fees Requirement: The Jefferson County Unified Development Code Chapter 18.30.080(1)(u) authorizes the Public Works Department to assess fees in accordance with the Jefferson County Fee Schedule Ordinance for development review activities including application and plan review, inspections, meetings, hearings, and final review. • Prior to DCD project approval, the proponent shall pay all costs related to the Department’s application review, plan review, inspections, and preparation of the Stormwater Management Facility Maintenance Agreement. In accordance with the Jefferson County Public Works Department Fee Schedule, the Department’s hourly development review fee is $95 for 2022 for greater than 8 hours of Department’s time. In the event that approval for the proposal is denied by Jefferson County or the proposal is not completed, the proponent shall still be responsible for paying the Department’s fee.