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2024126_YelmLoop_OakMitigationPlan FINAL OREGON WHITE OAK MITIGATION REPORT Olympic Region SR 510 Yelm Loop- New Alignment Phase 2 December 2024 Prepared By: Robert Phipps, PLA, PWS, ISA-CA, CESCL, Principal Landscape Architect WSDOT Olympic Region Environmental & Hydraulic Services Office Project Engineer: Grace Amundsen Barnkow, Project Engineer (360) 357-2600 WSDOT Olympic Region Title VI Notice to Public It is the Washington State Department of Transportation’s (WSDOT) policy to assure that no person shall, on the grounds of race, color, national origin or sex, as provided by Title VI of the Civil Rights Act of 1964, be excluded from participation in, be denied the benefits of, or be otherwise discriminated against under any of its federally funded programs and activities. Any person who believes his/her Title VI protection has been violated, may file a complaint with WSDOT’s Office of Equal Opportunity (OEO). For additional information regarding Title VI complaint procedures and/or information regarding our non- discrimination obligations, please contact OEO’s Title VI Coordinator at (360) 705-7090. Americans with Disabilities Act (ADA) Information This material can be made available in an alternate format by emailing the Office of Equal Opportunity at wsdotada@wsdot.wa.gov or by calling toll free, 855-362-4ADA(4232). Persons who are deaf or hard of hearing may make a request by calling the Washington State Relay at 711. SR 510 Yelm Loop – New Alignment Phase 2 December 2024 Oregon White Oak Mitigation Report i Executive Summary This report was prepared for Washington State Department of Transportation (WSDOT) Olympic Region in preparation for the second phase of the Yelm Loop project, adding a new three-mile stretch of roadway, for completion of an alternate route around the business district of the City of Yelm. The proposed project would connect the already constructed alternate state route (SR) 510 Yelm Loop Stage 1 in north Yelm, to main line SR 510, south of the town center. The project is anticipated to provide congestion relief for the City of Yelm, regional travel alternatives to I-5 during heavy traffic periods, improved safety, and promote economic vitality of local businesses. A Vegetation, Fish, Wildlife Discipline Report (FWV) was prepared in 2019 (Parametrix 2019), which identified priority habitat species, Oregon White Oak (Quercus garryana) within the study area. Per the report, both individual oaks and oak woodlands (OWO) were identified. Oak trees and stands of oak trees provide an important source of food, cover, nest sites, and arboreal movement routes for more than 200 species of vertebrate wildlife, including several species that are protected by state or federal law, such as the western gray squirrel (Sciurus griseus). OWO are identified as priority habitat by WDFW and protected by Yelm Municipal Code 18.21.110 A.1.b. Oak woodlands were avoided where practicable, and unavoidable impacts were minimized wherever feasible, however tree impacts are to occur. The project proposes to permanently impact approximately 0.43 acres of OWO. To mitigate for the unavoidable oak woodland impacts, WSDOT will implement a mitigation strategy to compensate for the loss of oak habitat. Compensatory mitigation will be implemented in accordance with the guidance outlined in WDFW Best management practices for mitigating impact to Oregon white oak priority habitats and Yelm’s Critical Area Ordinance. Proposed impacts and compensatory mitigation are summarized in Table 1. SR 510 Yelm Loop – New Alignment Phase 2 December 2024 Oregon White Oak Mitigation Report ii Table 1. Summary of project oak impacts and compensatory mitigation. Region Olympic Region Township/Range/Section Township 1 North, Range 5 East, Sections 17, 19, and 20 Permanent Oregon White Oak Woodland Impact 0.43 acres (55 trees, See Table 2) Mitigation Location Thurston County. Section 17, Township 17 North, Range 2 East, Willamette Meridian Area & Type of Mitigation · 0.65 acres Oak Woodland Establishment/Enhancement (Site 1 - WSDOT owned ROW) · 1.06 acres Oak Woodland Establishment/Enhancement/Preservation (Site 2 – Covenant Agreement) Years of Monitoring 5 Years *Acreage rounded to nearest hundredth SR 510 Yelm Loop – New Alignment Phase 2 December 2024 Oregon White Oak Mitigation Report iii Table of Contents Executive Summary ................................................................................................... i Figures ...................................................................................................................... iii Tables .......................................................................................................................iv Appendices ...............................................................................................................iv 1. Introduction ............................................................................................................ 5 2. Proposed Project ................................................................................................... 5 2.1. Project Location ........................................................................................................ 5 2.2. Project Purpose and Description ........................................................................... 5 3. Existing Conditions ................................................................................................ 8 3.1. Landscape Setting ................................................................................................... 8 4. Oak Woodland Impact Assessment ...................................................................... 9 5. Mitigation Strategy ................................................................................................. 9 5.1. Oak Woodland Mitigation Sites ............................................................................ 10 6. Mitigation Goals, Objectives and Performance Criteria ....................................... 11 6.1 Goals ..................................................................... Error! Bookmark not defined. 6.2 Objectives .............................................................. Error! Bookmark not defined. 6.3 Performance Criteria ............................................. Error! Bookmark not defined. 6.4 Monitoring .............................................................. Error! Bookmark not defined. 6.5 Contingency Plan .................................................. Error! Bookmark not defined. 6.5.1 Vegetation ............................................................................................................... 16 6.5.2 Protection BMPs ...................................................... Error! Bookmark not defined. 6.6 Site Management and Establishment .................................................................. 16 7. References .......................................................................................................... 17 Figures Figure 1. Vicinity Map……………………………………………………..……………….3 Figure 2. Photo of Site 2 Oak Mitigation Site (from WSDOT 2024).Error! Bookmark not defined. SR 510 Yelm Loop – New Alignment Phase 2 December 2024 Oregon White Oak Mitigation Report iv Tables Table 1. Summary of project oak impacts and compensatory mitigation…..........…ii Table 2. Summary of Oregon White Oaks………………………………….............…4 Table 3. Monitoring Schedule…………….……………………………………...........10 Table 4. Monitoring report recipients..….…………………………………….............10 Appendices Appendix A. Mitigation Site 1& 2 – Existing Conditions Appendix B. Mitigation Site 1 & 2 – Site and Soil Preparation Appendix C. Mitigation Site 1 & 2 – Planting Plan SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan 1. Introduction The Washington State Department of Transportation (WSDOT) proposes to construct the remaining segment of State Route (SR) 510 Alternate Route in Yelm, Washington. Phase 1 of the Yelm Loop Project, extending from Mud Run Road to Cullens Road in northwestern Yelm, was completed in 2010. The Phase 2 project segment that is the subject of this review would extend the highway to meet SR 507 near the southeastern corner of the city. The full project (including Phase 2) underwent National Environmental Policy Act (NEPA) review in 2000, followed by a NEPA re-evaluation and Endangered Species Act (ESA) consultation in 2007 and 2008. The project design currently under review is largely identical to the design that was reviewed in 2008. The current design includes two modifications that influence the project’s potential impacts to the environment: · The shared-use paths previously planned for both sides of the roadway have been combined into a single shared use-path along the south/west side of SR 510 from Cullens Road to 103rd Avenue. · The stormwater concept employs linear infiltration facilities instead of relying on conveyance and ponds. Compared to the earlier design, both of these modifications reduce the amount of ground- disturbing work needed for project construction. This report identifies the proposed OWO impacts and mitigation strategy to offset the anticipated habitat loss. 2. Proposed Project 2.1. Project Location The proposed project occurs at the eastern edge of Thurston County, Washington, in the City of Yelm and in portions of unincorporated Thurston County (Figure 1). The project spans Sections 17, 18, 20, and 29, Township 17 North, Range 2 East, Willamette Meridian. 2.2. Project Purpose and Description Phase 2 of the Yelm Loop Project proposes to construct the remaining three miles of SR 510 Alternate Route through WSDOT ROW in the City of Yelm, Washington. Stage 1 of the Yelm Loop Project has already been completed. The proposed Phase 2 project will extend the configuration of Stage 1 design components, consisting of a two-lane highway with bicycle and pedestrian facilities, between Cullins Road and 170th Street Southeast, and will connect the Stage 1 portion of SR 510 Alternate Route, around downtown Yelm, back to the SR 510 mainline, southwest of the primary business district. Traffic volumes on existing SR 510/Yelm Avenue, the main street running through the City of Yelm, are heavy during commute times, build when I-5 becomes congested and travelers choose this route as an alternative, as well as heavier volumes experienced during summer travel. Providing this alternate route will address congestion and safety issues along SR 510/Yelm Avenue and will result in: · improved regional travel times · reduced traffic volume and congestion through the Yelm business district SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan · contributions to the economic vitality of local businesses · reduced potential collisions · a new route for bicyclists and pedestrians · improved emergency response times SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan Figure 1. Vicinity Map Oak Mitigation Site 1 and 2 SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan 3. Existing Conditions 3.1. Landscape Setting The project is located in the city of Yelm and City of Yelm urban growth area (UGA), within the Nisqually watershed, Water Resource Inventory Area (WRIA) 11. The area is known for unique historic prairie habitats formed on glacial outwash soils within the Nisqually river watershed. Mount Rainier and its western foothills lie to the east of the project and the Nisqually River delta lies to the west. Vegetation communities typical of the Yelm Prairie area include Oregon white oak (Quercus garryana) and Douglas-fir (Pseudotsuga menziesii) stands with grass and wildflower prairie habitat in between. Scattered native shrub communities are also established in some areas. Scotch broom (Cytisus scoparius) and Himalayan blackberry (Rubus armeniacus) are common invasive species established in the area. The project area is ten miles southeast of the Nisqually River estuary on the shore of South Puget Sound and is situated at 300 feet above sea-level (Appendix A-4). The project is in the lower Nisqually River – Frontal Puget Sound Watershed (5th hydrologic unit code - 1711001503) in Water Resource Inventory Area (WRIA) Nisqually 11. Land use immediately surrounding the project includes residential, commercial development, prairies, pasture, and hay-fields. The Centralia City Light, Yelm Hydroelectric Canal lies to the north of the project, between the WSDOT ROW and the Nisqually River. Figure 2. Photo of Site 2 Oak Mitigation Site (from WSDOT 2024). SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan 4. Oak Woodland Impact Assessment This chapter summarizes the existing conditions of the Oregon White Oak woodland proposed to be impacted, a general assessment of impacts to Oak woodlands and functions related to the proposed project, and minimization efforts used to reduce natural resource impacts. WSDOT has taken appropriate and practicable steps to avoid and minimize adverse impacts Oak Woodland habitat. Total avoidance was not possible due to constraints associated with safety and design-guidelines, the close proximity of resources to existing highway embankments, and the linear nature of transportation projects. Several phases of review and alternative analysis were conducted to identify the proposed project as the alternative that best meets the design objectives while minimizing environmental impacts. See reference document, Supplemental Biological Assessment – SR510, Yelm Loop – New Alignment Phase 2 –, (Parametrix 2020) for additional information on avoidance and minimization efforts through design alternatives. Additional information on the overall habitat impacts is also described within. The project proposes to permanently impact approximately 0.43 acres of OWO. Below describes impacts by each individual tree and sizes. Table 2. Summary of Oregon White Oak impacts. Quantity Size Location Yelm Creek Flume Road East of Flume Road 4” to 15” DBH 32 2 0 16” to 30” DBH 17 0 3 >30” DBH 1 0 0 Total 50 2 3 5. Mitigation Strategy To mitigate for unavoidable impacts to priority habitat areas (Oregon White Oaks), a comprehensive mitigation strategy will be implemented in accordance with the guidance outlined in WDFW Best management practices for mitigating impact to Oregon white oak priority habitats, USDA Planting Native Oak in the Pacific Northwest and Yelm’s Critical Area Ordinance. Proposed impacts and compensatory mitigation are summarized in Table 1. WSDOT proposes to use two sites (Site 1 and Site 2) to satisfy the mitigation requirement in SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan consultation with WDFW. Both sites are located approximately 1 mile west of the western project terminus and directly adjacent to SR510 ROW. Site 1 is a WSDOT owned parcel adjacent to the agency’s right of way originally acquired for mitigation opportunity. The 2.38 acres additional ROW area site is intermixed by a range of species including the tree species Douglas fir (Pseudotsuga menziesii), big-leaf maple (Acer macrophyllum), shore pine (Pinus contorta), and a single mature Oregon white oak (Quercus garryana). Understory varies from typical native species, such as serviceberry (Amelanchier alnifolia), sword fern (Polystichum munitum), and salal (Gaultheria shallon), snowberry (Symphoricarpos albus), Himalayan blackberry (Rubus armeniacus), osoberry (Oemleria cerasiformis), beaked hazelnut (Corylus cornuta), black hawthorn (Crataegus douglasii), tall Oregon grape (Mahonia aquifolium) to non-native shrubs, Himalayan blackberry (Rubus armeniacus), Scotch broom (Cytisus scoparius) and grasses and forbs. Grasses and forbs dominate the majority of the cover. 0.65 acres will be utilized in conjunction with the full parcel area of Site 2 for mitigation purposes to enhance and create new oak habitat. See Figure 1. Site 2 is a property that will be placed in a convenance through an agreement between the property owner and WSDOT. The agreement will place the property into perpetuity for establishment and management of the site as an OWO habitat for mitigation. The 1.06 acres area site is primarily dominated by tree species of Oregon white oak (Quercus garryana) and fringe shore pine (Pinus contorta) along the north and west property lines. Within the southern half of the triangle parcel and immediately adjacent to Alternate SR510 is dominated by Scotch broom (Cytisus scoparius) with non-native grasses intermixed with some volunteer sapling Oregon white oak (Quercus garryana). Along the northern half is mature Oregon white oak (Quercus garryana) in a mostly contiguous canopy with understory of snowberry (Symphoricarpos albus), serviceberry (Amelanchier alnifolia), black hawthorn (Crataegus douglasii) and native rose (Rosa spp.) with grasses and forbs. The entire area will be utilized for mitigation purposes for preservation, enhancement and establishment of new oak habitat. See Figure 2. 5.1. Oak Woodland Mitigation Sites WSDOT will establish and enhance existing oak habitat through development of a comprehensive mitigation strategy to restore and reduce competition through invasive weed removal and restoration of OWO woodland habitat through planting and long-term management. Specific mitigation components include: · Establish and enhance 0.65 acres of disturbed Oregon White Oak Woodland (invasive species removal, canopy and understory planting) at Site 1 · Establish and enhance 1.06 acres of disturbed Oregon White Oak Woodland (invasive species removal, canopy and understory planting) at Site 2. This area includes 0.32 acres of the total area for preservation of mature Oregon White Oak canopy. The mature Oregon White Oak area includes over 20 trees ranging from 10” DBH and larger extending a contiguous habitat corridor north off the mitigation parcel. With favorable native soil conditions, targeted weed removal, existing habitat presence (saplings and mature oaks), regular site management, WSDOT anticipates long term success at each of the sites. Both proposed sites contain similar soils to the impacted SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan OWO areas, provide direct access from SR510 for initial construction and on-going maintenance activities. Summer construction related work will identify desirable vegetation to be retained including native understory, mature oaks and oak saplings. Tree protection fencing and or flagging will clearly delineate the existing vegetation to be retained. Weed control will be conducted within invasive Scotch broom and nuisance grasses by hand methods only to reduce soil compaction and maintain favorable planting mediums. No herbicide treatment will be allowed for initial weed control activities. Though fringe conifer tree species are present of existing OWO habitat, none are within WSDOT owned property to alleviate competition and overshadowing by removal or stump cutting. Acorn harvesting from existing OWO trees on each site will be completed in September with dormant season planting of new oaks/acorns within the same year. Acorn use from within the same project footprint will retain site specific genetic ecosystem makeup of nearby well-established OWO habitat. Planting holes, 12 inches deep and 2 feet wide, will be amended with compost to increase organics, beneficial mycorrhizal fungi, water absorption/infiltration and nutrient cycling production. Up to three acorns will be installed within each amended soil pit in naturalized groupings at approximately 8’ o.c. spacing. The extra acorns per hole are in response to expected mortality. If establishment is good, the acorn growth will likely fuse together naturally. The acorns will be planted within the top 1-2 inches below the surface. Each planting hole will be covered in a 3-inch depth of organic mulch to reduce weed competition post planting. Weed mats, protection tubings, or other landscape fabrics may be employed if weed competition is excessive or animal browsing becomes problematic. A specific quantity and location of the planting holes will be determined based on success of acorn harvesting and existing oaks fully identified within the proposed planting areas. It is desired to WSDOT expects acorn harvesting to be successful to fulfill the needs for restoration, however, as a contingency, purchase of containerized or seedling material may be needed to complete first year planting. If additional acorns remain after planting, WSDOT will make consolidated efforts to properly store the acorns for replanting in follow up years. At year 3 post planting with successful oak establishment, woody shrub understory (snowberry, rose, hawthorn, others) may be planted at approximately 4’ o.c. spacing with concurrence by WDFW to extend the native understory footprint. This delayed understory approach will reduce resource competition of nutrients and water for greater success of new planting oak acorns in Years 1 and 2. 6. Mitigation Goals, Objectives and Performance Criteria The proposed OWO mitigation sites will be monitored for 5 years to demonstrate that the intended goals and objectives are met. Goals describe the overall intent of mitigation efforts, and objectives describe individual components of the mitigation site in detail. Performance measures and performance standards describe specific on-site characteristics that indicate a function is being provided. Performance measures are used to guide management of the mitigation site. Performance standards are used to evaluate compliance with regulatory permits in the final year of monitoring. Contingency plans describe what actions can be taken to correct site deficiencies. SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan WSDOT uses the adaptive management process to improve mitigation and restoration success. Adaptive management involves learning from monitoring and implementing management activities, such as implementing parts of the site management or contingency plans. Information from monitoring is used to direct subsequent site management activities. As part of the adaptive management process, mid-course corrections may necessitate a change in vision for the site if nature takes its course and things turn out differently than planned. A change in vision may require renegotiation with regulators for a new set of performance standards. 6.1. Goals The goal of the proposed compensatory mitigation is to ensure that no functional loss of priority habitat species, Oregon White Oak woodlands. The two off-site mitigation areas are expected to provide the following function: · Preserve significant Oregon White Oak woodland habitat · Restore and increase the aerial extent and associated function of Oregon White Oak woodland in the project vicinity 6.2. Objectives The following list of objectives describes the proposed mitigation at the various natural resource mitigation sites and within the project limits: · Establish and enhance 0.65 acres of disturbed Oregon White Oak Woodland (invasive species removal, canopy and understory planting) at Site 1. · Establish and enhance 1.06 acres of disturbed Oregon White Oak Woodland (invasive species removal, canopy and understory planting) at Site 2. · Promote the development of native oak woodland plant communities including understory by limiting the growth and spread of noxious and nuisance vegetation, including Himalayan Blackberry, Scotch Broom and other nuisance woody species. · Preserve and create habitat corridor connectivity in association with priority habitat species. 6.3. Performance Criteria The performance standards described below provide benchmarks for measuring achievement of the goals and objectives of the mitigation site. Mitigation activities are intended to meet these performance standards within a specified time frame. Monitoring of mitigation success standards begins immediately following initial planting with the collection of baseline data and initial (year 1) survival standards. Objective 1: Restore or establish at least 1.72 acres of OWO habitat at the mitigation sites. Restore Oregon White Oak woodland function and provide increased habitat by promoting the development of OWO associated native plant communities. Performance Standards Monitoring Methods 1A Success Standard The OWO woodland on Site 1 and 2 mitigation sites will be revegetated in accordance with the Soil As-built plans documenting that the restoration areas have been planted according to the planting plan will be submitted within year 1. SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan Preparation/Planting Plans, and final PS&E documents. 1B Success Standard At monitoring year 1, there will be a minimum survival rate of 100% in oaks at each site. Conduct plant assessment of contract- installed vegetation (plant counts based on as-built plans). 1C Success Standard At monitoring year 3, there will be a minimum density and/or survival of native woody trees and/or shrubs planting areas as follows: · minimum density of 100 living native trees (includes existing trees and volunteers) per acre or a minimum survival rate of 90%. · minimum density of 500 living native shrubs per acre when included in woody species understory planting areas in Year 3 only. Use current monitoring protocols (see Monitoring Plan) to determine density (number of living trees and shrubs per acre). 1D Success Standard At monitoring year 5, there will be a minimum density of native woody trees and/or shrubs planting areas as follows: · minimum density of 75 living native trees (includes existing trees and volunteers) per acre. · minimum density of 400 living native shrubs per acre when included in woody species planting areas by Year 5. Use current monitoring protocols (see Monitoring Plan) to determine density (number of living trees and shrubs per acre). Contingency: If the monitoring reports indicate insufficient establishment and/or plant survival, those areas not meeting current-year standard(s) will be replanted to bring them in compliance with the failing current-year standard(s). Objective 2: Promote the development of native Oregon White Oak woodland associated plant communities by limiting the growth and spread of noxious and nuisance vegetation. Performance Standards Monitoring Methods 2A. Performance Standard Conduct a pre-construction survey of the existing extent of invasive vegetation at the mitigation sites 1 and 2, to establish a baseline for invasive species monitoring and management at years 1, 3, and 5. Provide photographic and map (GPS or notations on plan sheets) documentation of existing stands of nuisance vegetation including Scotch Broom and Himalayan Blackberry. SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan 2B. Performance Standard At monitoring years 1, 3, and 5, Invasive Species will be managed as follows: The aerial extent of Class B and Class C noxious weeds will not exceed 15% in the planting areas, exclusive to each mitigation site (ie – invasive species totals at both sites shall not be added together to create a single % cover for reporting purposes). Class A Noxious weeds If/when detected, Class A Noxious Weeds, shall be treated so that the species do not exist on the site. These species shall not be included in the 15% cover allowed for invasive species. Observe and map (notations on plan sheets) locations of nuisance weeds (Class B and C) as part of annual vegetation surveys using current monitoring techniques. For larger stands, GPS measurements of stand perimeters will be provided to measure the extent of change over time. Observations will form the basis of on-going site management and integrated vegetation management activities. Use current monitoring protocols (see Monitoring Plan) to determine species composition as a basis for potential treatment options. Contingency: Implement a long-term integrated vegetation management plan to maintain the aerial extent of invasive species or non-native pasture grasses and forbs at or below the established thresholds. Weed management activities may be conducted in all monitoring years. 6.4. Monitoring WSDOT staff will monitor the mitigation sites for 5 years after initial installation. The monitoring objective for the mitigation areas is to achieve the prescribed standards unless WSDOT, in consultation with the regulatory agencies, establish replacement standards based on circumstances and conditions observed at the mitigation sites. If all performance standards are achieved in less than 5 years, WSDOT may terminate monitoring with approval of the review agencies. A quantitative monitoring plan will be developed and implemented (beginning in the first growing season following project acceptance -1 year following initial installation) that addresses the standards listed in this plan. The site will be monitored in years 1, 3, and 5 by the WSDOT Mitigation Monitoring Program to evaluate compliance with performance standards, formal monitoring. In formal monitoring years, years 1, 3, and 5 reports of the formal monitoring will be prepared and submitted to the WDFW and City of Yelm. Additional monitoring will occur in intervening non-report years in order to inform and guide site development activities, informal monitoring. Successful mitigation will be measured by attainment of the performance standards described in the mitigation plan. The Mitigation Monitoring Program uses objective-based monitoring to document the condition of WSDOT’s mitigation sites. Monitoring protocols are selected based on objectives specified in the mitigation plan, and evaluation of current site conditions. Quantitative data collection techniques presently in use are based on standard ecological and biostatistical methods described in Bonham (1989), Elzinga et al. (1998), Krebs (1999), Zar (1999), and other sources. The monitoring program’s current monitoring methods include the key concepts of objective-based monitoring, adaptive management, and SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan statistical rigor. Quantitative monitoring methods employed involve sample size analyses and may include the point-line, point-frame, quadrat, and line-intercept methods as defined by the works cited above. Formal and informal monitoring of the mitigation site will occur over the 5-year monitoring period. Table 3 lists the monitoring schedule for the mitigation sites. Successful mitigation will be measured by attainment of the performance standards described in this mitigation plan document. Monitoring and establishment/contingency activities will cease as soon as all success standards have been attained. Table 3. Monitoring Schedule. Monitoring Year Formal Informal 1 Yes quarterly site visits 2 No quarterly site visits 3 Yes quarterly site visits 4 No quarterly site visits 5 Yes quarterly site visits Table 4. Monitoring report recipients. Permitting Agency or Organization Contact Name and Email WDFW Portia Leigh Portia.Leigh@dfw.wa.gov City of Yelm Gary Cooper GaryC@Yelm.wa.gov WSDOT has established a comprehensive set of monitoring methods that are based primarily on Elzinga et al. (1998). The actual methods used to monitor each site are documented in annual monitoring reports prepared by WSDOT’s Wetland Assessment and Monitoring Program, which is based in the Environmental Services Office in Olympia, Washington. Some variation of the methods occurs as techniques are improved, or standards change. 6.5. Contingency Plan WSDOT anticipates the mitigation goals will be accomplished with the construction and installation of the mitigation design as shown on the grading and planting plans. Contingency actions, however, may be needed to correct unforeseen problems. Contingency revisions typically require coordination with the permitting agencies. Type of Monitoring SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan As necessary, contingency measures (such as adaptive management options or revisions to performance criteria with permitting agency agreement) will be implemented to meet performance measures and performance standards. The following describes potential situations that may occur and the potential contingencies that might be implemented to correct the problem. Because not all site conditions can be anticipated, the contingencies discussed below do not represent an exhaustive list of potential problems or remedies. 6.5.1 Vegetation Problems related to vegetation include plant mortality, and poor growth resulting in low plant cover. These problems could be the result of insufficient site management, particularly watering in the first few growing seasons, animal browse, competition from invasive species, incorrect plant selection, altered site conditions, and vandalism. Contingencies for plant mortality and poor plant cover may include:  Plant replacement – Additional planting may be required to meet plant survival and plant cover requirements. Plant species will be evaluated in relation to site conditions to determine if plant substitutions will be required.  Supplemental watering – Temporary watering or irrigation system may be necessary for initial and on-going establishment.  Weed control – Control of non-native invasive species may be required to meet survival and plant cover requirements. Weed control methods could include mechanical or hand control, mulching, or herbicide application.  Herbivore control – If plant survival or vegetation cover standards are not met because of animal browse, the wildlife responsible will be identified and appropriate control measures will be attempted. This could include plant protection, fence installation, or the use of repellents.  Vandalism – To prevent vegetation disturbance from vandalism, fence installation and sensitive area signage may be installed.  Review and revise performance criteria with permitting agency agreement. 6.6 Site Management and Establishment WSDOT will manage the mitigation sites annually for 5 years following initial project acceptance. Site management and establishment activities will include plant replacement, vegetation management (including noxious weed control) and may include mulching, fertilizing, supplemental watering, maintenance of access control (fences and gates), repairing damage from vandals, correcting erosion or sedimentation problems, or litter pickup. Suppression and control of these invasive plants will require careful site preparation and active site management. While complete elimination of Scotch Broom and Himalayan blackberry from the mitigation sites may not be possible, they should be managed sufficiently to ensure survival of the native planted species until they can effectively compete. SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan 7. References City of Yelm. (2024). City of Yelm Municipal Code. Chapter 18.21 Critical Areas and Resource Lands, Section 18.21.060 Wetlands, and Section 18.21.110 Fish and Wildlife Habitat Conservation Areas. https://www.codepublishing.com/WA/Yelm/html/Yelm18/Yelm1821.html#18. United States Department of Agriculture (USDA). Planting Native Oak in Pacific Northwest. February 2010. Washington State Department of Fish and Wildlife. (n.d.b). PHS on the Web. Retrieved April 24, 2024 from https://geodataservices.wdfw.wa.gov/hp/phs/ Washington State Department of Fish and Wildlife. Best management practices for mitigating impacts to Oregon White Oak priority habitat. January 2024. Washington State Department of Transportation. (2018). Wetland Assessment Report – SR 510/Yelm Loop – New Alignment Phase 2. December 2018. Washington State Department of Transportation (SCJ Alliance). Vegetation, Fish and Wildlife Discipline Report: SR 510/Yelm Loop – New Alignment Phase 2. December 2019. Washington State Department of Transportation (Parametrix). Supplemental Biological Assessment – SR510, Yelm Loop – New Alignment Phase 2. 2020. SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan Appendix A. Existing Conditions Appendix A includes the following sub-appendices: A-1 Existing Conditions – Site 1 A-2 Existing Conditions – Site 2 FILE NAME TIME DATE DESIGNED BY ENTERED BY CHECKED BY PROJ. ENGR. REGIONAL ADM.REVISION DATE BY SHEET OF SHEETS Washington State Department of Transportation P.E. STAMP BOX P.E. STAMP BOX DATE DATE LOCATION NO.CONTRACT NO. JOB NUMBER REGION NO. STATE FED.AID PROJ.NO. WASH PLOTTED BY PLAN REF NO PhippsRo 11/26/2024 7:18:18 AM c:\users\phippsro\pw_wsdot\d0777071\OakExhibitSite1.dgn 10 SCALE IN FEET 0 40 80 LEGEND WSDOT LIMITED ACCESS PARCEL BOUNDARY (NOT SURVEYED) EXISTING FENCE (10" DBH AND GREATER) EXISTING OAK TREE (TREES GREATER THAN 4" DBH) EXISTING OAK TREE DRIPLINE TREE ID SPECIES SIZE (DBH)NOTES STOR M POND EXISTING SR510 EXTENTS OF NUISANCE VEG (4x4 WOOD POSTS, 50' O.C.) MANAGEMENT AREA DELINEATED MARKER FOR FOR CONSTRUCTION ACCESS EXISTING GATE NEW ALIGNMENT PHASE 2 YELM LOOP EXISTING CONDITIONS - SITE 1 R. PHIPPS R. PHIPPS R. PHIPPS S. ROARK G. AMUNDSEN BARNKOW SR 510 1 LEGEND FILE NAME TIME DATE DESIGNED BY ENTERED BY CHECKED BY PROJ. ENGR. REGIONAL ADM.REVISION DATE BY SHEET OF SHEETS Washington State Department of Transportation P.E. STAMP BOX P.E. STAMP BOX DATE DATE LOCATION NO.CONTRACT NO. JOB NUMBER REGION NO. STATE FED.AID PROJ.NO. WASH PLOTTED BY PLAN REF NO PhippsRo 11/26/2024 7:36:28 AM c:\users\phippsro\pw_wsdot\d0777071\OakExhibitSite2.dgn 10 WSDOT LIMITED ACCESS PARCEL BOUNDARY (NOT SURVEYED) SR510 EXISTING ASPHALT TRAIL EXISTING FENCE TREE ID SPECIES SIZE (DBH) (10" DBH AND GREATER) EXISTING OAK TREE (6" - 10" DBH) EXISTING OAK TREE (4" DBH TO SAPLING) EXISTING OAK TREE (TREES GREATER THAN 4" DBH) EXISTING OAK TREE DRIPLINE (SCOTCH BROOM) EXTENTS OF NUISANCE VEG STORM PONDEXISTING SR 510 NEW ALIGNMENT PHASE 2 YELM LOOP LP8 EXISTING CONDITIONS - SITE 2 SCALE IN FEET 0 40 80 NOTES TREE ID SPECIES SIZE (DBH)NOTES R. PHIPPS R. PHIPPS R. PHIPPS S. ROARK G. AMUNDSEN BARNKOW CONSTRUCTION ACCESS X5502 X5503 X5505 X5506 X5507 X5508 X5509 X5600 X5601 X5603 X5604 X5605 X5607 X5608 X5609 X5511 X5512 X5513 X5514 X5515 X5516 X5517 X5518 X5519 X5610 X5611 X5612 X5613 X5616 X5617 X5618 X5520 X5521 X5522 X5523 X5524 X5525 X5526 X5528X5529 X5622 X5623 X5624 X5626 X5627 X5628 X5531 X5532 X5533 X5534 X5535 X5536 X5537 X5538 X5539 X5540 X5541 X5542 X5543 X5544 X5545 X5546 X5547 X5548 X5549 X5550 X5551 X5552 X5553 X5554 X5555 X5556 X5557X5558 X5559 X5560 X5562 X5563 X5564 X5565 X5566 X5567 X5568 X5569 X5570 X5572 X5573 X5575 X5576 X5577 X5579 X5485 X5486 X5487 X5488 X5489 X5580 X5581 X5582 X5583 X5584 X5585 X5586 X5587 X5589 X5490 X5493 X5494 X5496 X5497 X5498 X5590 X5591 X5592 X5593 X5594 X5596 X5597 X5598 X5599 SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan Appendix B. Site Preparation Appendix B includes the following sub-appendices: B-1 Site Preparation Plan – Site 1 B-2 Site Preparation Plan – Site 2 FILE NAME TIME DATE DESIGNED BY ENTERED BY CHECKED BY PROJ. ENGR. REGIONAL ADM.REVISION DATE BY SHEET OF SHEETS Washington State Department of Transportation P.E. STAMP BOX P.E. STAMP BOX DATE DATE LOCATION NO.CONTRACT NO. JOB NUMBER REGION NO. STATE FED.AID PROJ.NO. WASH PLOTTED BY PLAN REF NO PhippsRo 11/26/2024 11:35:52 AM c:\users\phippsro\pw_wsdot\d0152581\XL5607_PS_LS7.dgn 10 SCALE IN FEET 0 40 80 LEGEND WSDOT LIMITED ACCESS PARCEL BOUNDARY (NOT SURVEYED) EXISTING FENCE (10" DBH AND GREATER) EXISTING OAK TREE STOR M POND EXISTING SR510 NEW ALIGNMENT PHASE 2 YELM LOOP R. PHIPPS R. PHIPPS R. PHIPPS S. ROARK G. AMUNDSEN BARNKOW SR 510 CONSTRUCTION NOTES 1 2 3 4 3 1 2 1 2 3 LEGEND / SUMMARY OF QUANTITIES SYMBOL 1 EA 1EXISTING FENCE GATE (6' LENGTH, 2' BURIED) 4X4 WOOD POST EA 10 PER SPECIAL PROVISIONS SELECTIVE CLEARING 2 3 #UNIT TOTALITEM AC 0.53 EXISTING OAK TREE DRIPLINE POSTS AT 50' O.C. AND STAKED LOCATIONS INSTALL 4X4 WOOD (NON-TREATED) CEDAR OR DOUG FIR AND LOCKING THROUGHOUT LIFE OF CONTRACT EXISTING FENCE GATE - ENSURE PROPER OPERATION 4 5 AS DIRECTED BY ENIGNEER. ELIMINATE AREAS OF COMPACTION PER SECTION 8-02.3(5) 5 SITE PREPARATION - SITE 1 LP7 EXTEND TREATMENT TO R.O.W. FENCE OR AS DIRECTED. SEE SPECIAL PROVISIONS. NO MOTORIZED VEHICLE EQUIPMENT ALLOWED. SELECTIVE CLEARING AT THE DIRECTION OF ENGINEER. 5 ENGINEER PER STANDARD SPECIFICATIONS 1-07.16(2). PROTECT EXISTING NATIVE VEGETATION AS DIRECTED BY LEGEND FILE NAME TIME DATE DESIGNED BY ENTERED BY CHECKED BY PROJ. ENGR. REGIONAL ADM.REVISION DATE BY SHEET OF SHEETS Washington State Department of Transportation P.E. STAMP BOX P.E. STAMP BOX DATE DATE LOCATION NO.CONTRACT NO. JOB NUMBER REGION NO. STATE FED.AID PROJ.NO. WASH PLOTTED BY PLAN REF NO PhippsRo 11/26/2024 11:36:16 AM c:\users\phippsro\pw_wsdot\d0152581\XL5607_PS_LS8.dgn 10 WSDOT LIMITED ACCESS PARCEL BOUNDARY (NOT SURVEYED) SR510 EXISTING ASPHALT TRAIL EXISTING FENCE (10" DBH AND GREATER) EXISTING OAK TREE (6" - 10" DBH) EXISTING OAK TREE (4" DBH TO SAPLING) EXISTING OAK TREE (TREES GREATER THAN 4" DBH) EXISTING OAK TREE DRIPLINE STORM PONDEXISTING SR 510 NEW ALIGNMENT PHASE 2 YELM LOOP LP8 SCALE IN FEET 0 40 80 R. PHIPPS R. PHIPPS R. PHIPPS S. ROARK G. AMUNDSON BARNKOW CONSTRUCTION NOTES 1 2 3 4 1 2 3 LEGEND / SUMMARY OF QUANTITIES SYMBOL EA 1 LF 10 PER SPECIAL PROVISIONS SELECTIVE CLEARING #UNIT TOTALITEM AC 0.53 (MATCH EXTG FENCE) CHAIN LINK FENCE GATE EXISTING FENCING TYPE AND STYLE. INSTALL NEW CHAIN LINK FENCE GATE. MATCH 1 1 3 4 3 ENGINEER PER STANDARD SPECIFICATIONS 1-07.16(2). PROTECT EXISTING NATIVE VEGETATION AS DIRECTED BY SEE SPECIAL PROVISIONS. MOTORIZED VEHICLE EQUIPMENT ALLOWED. SELECTIVE CLEARING AT THE DIRECTION OF ENGINEER. NO EXTEND TREATMENT TO R.O.W. FENCE OR AS DIRECTED. 5 INSTALL HI-VIS CONSTRUCTION FENCING. 2 2 5 TYPICAL TYPICAL 5 FENCING HI-VIS CONSTRUCTION SITE PREPATION - SITE 2 SR 510 Yelm Loop – New Alignment Phase 2 December 6, 2024 Oregon White Oak Mitigation Plan Appendix C. Site Preparation Appendix C includes the following sub-appendices: C-1 Planting Plan – Site 1 C-2 Planting Plan – Site 2 FILE NAME TIME DATE DESIGNED BY ENTERED BY CHECKED BY PROJ. ENGR. REGIONAL ADM.REVISION DATE BY SHEET OF SHEETS Washington State Department of Transportation P.E. STAMP BOX P.E. STAMP BOX DATE DATE LOCATION NO.CONTRACT NO. JOB NUMBER REGION NO. STATE FED.AID PROJ.NO. WASH PLOTTED BY PLAN REF NO PhippsRo 11/26/2024 11:38:37 AM c:\users\phippsro\pw_wsdot\d0152581\XL5607_PS_LS9.dgn 10 SCALE IN FEET 0 40 80 STOR M POND EXISTING SR510 NEW ALIGNMENT PHASE 2 YELM LOOP R. PHIPPS R. PHIPPS R. PHIPPS S. ROARK G. AMUNDSEN BARNKOW SR 510 1 NOT TO SCALE PLACED WITHIN 2" OF SURFACE) OAK ACORNS (THREE PER HOLE OAK ACORN PLANTING HOLES 150 OAKS PLACE APPROX. 8' O.C. AND WHERE STAKED THIS SHEET. THREE ACORNS PER HOLE. TOTAL PLANTING HOLE QUANTITY PLANTING PLAN - SITE 1 D E P T H 12 I N C H COMPACT. BACKFILL MATERIAL. DO NOT ACORNS WITHIN 2" OF TOP OF COMPOST SOIL BLEND. PLACE CIRCLE. BACK FILL WITH AMENDED NATIVE SOIL IN A ONE FOOT WIDE EXCAVATE AND LOOSEN EXISTING ACORNS WIDE. PULL BARK MULCH AWAY FROM 2"-3" DEPTH OF BARK MULCH, 2 FEET 2 FEET BARK MULCH RING LEGEND WSDOT LIMITED ACCESS PARCEL BOUNDARY (NOT SURVEYED) EXISTING FENCE EXISTING OAK TREE FILE NAME TIME DATE DESIGNED BY ENTERED BY CHECKED BY PROJ. ENGR. REGIONAL ADM.REVISION DATE BY SHEET OF SHEETS Washington State Department of Transportation P.E. STAMP BOX P.E. STAMP BOX DATE DATE LOCATION NO.CONTRACT NO. JOB NUMBER REGION NO. STATE FED.AID PROJ.NO. WASH PLOTTED BY PLAN REF NO PhippsRo 11/26/2024 11:38:58 AM c:\users\phippsro\pw_wsdot\d0152581\XL5607_PS_LS10.dgn 10 SR510 EXISTING ASPHALT TRAILSTORM PONDEXISTING SR 510 NEW ALIGNMENT PHASE 2 YELM LOOP LP8 SCALE IN FEET 0 40 80 R. PHIPPS R. PHIPPS R. PHIPPS S. ROARK G. AMUNDSON BARNKOW NOT TO SCALE PLACED WITHIN 2" OF SURFACE) OAK ACORNS (THREE PER HOLE OAK ACORN PLANTING HOLES D E P T H 12 I N C H COMPACT. BACKFILL MATERIAL. DO NOT ACORNS WITHIN 2" OF TOP OF COMPOST SOIL BLEND. PLACE CIRCLE. BACK FILL WITH AMENDED NATIVE SOIL IN A ONE FOOT WIDE EXCAVATE AND LOOSEN EXISTING ACORNS WIDE. PULL BARK MULCH AWAY FROM 2"-3" DEPTH OF BARK MULCH, 2 FEET 2 FEET BARK MULCH RING 50 OAKS PLACE APPROX. 8' O.C. AND WHERE STAKED THIS SHEET. THREE ACORNS PER HOLE. TOTAL PLANTING HOLE QUANTITY 50 OAKS PLACE APPROX. 8' O.C. AND WHERE STAKED THIS SHEET. THREE ACORNS PER HOLE. TOTAL PLANTING HOLE QUANTITY LEGEND WSDOT LIMITED ACCESS PARCEL BOUNDARY (NOT SURVEYED) EXISTING FENCE EXISTING OAK TREE PLANTING PLAN - SITE 2