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HomeMy WebLinkAbout50- UPLAND RESTORATION MEMOWET.LAND, LLC 8201 164TH AVE NE, SUITE 200, PMB 141, REDMOND, WA, 98052 206-309-8100 Upland Restoration Memo To: Ann Burkhart From: Jennifer Marriott Date: 22 July 2022 Property: Pomona Woods The County approved a small driveway/access stub that was constructed prior to establishing the final driveway alignment. Since the driveway alignment has since been adjusted to avoid impacts to a wetland buffer, the portions of this driveway stub that are outside of the new driveway will be restored as native, upland forest. The upland restoration proposed will occur outside of all critical areas. This memo summarizes the proposed voluntary upland restoration actions. Agency Policies and Guidance The proposed restoration plan was designed in accordance with the policies and guidance provided in the following documents - Jefferson County Code (JCC) Chapter 18.22 Critical Areas. No other agencies have jurisdiction over the upland restoration area. Proposed Restoration Components The mitigation plan includes the restoration of 1,978 square feet of uplands located outside of any designated critical areas. A planting plan is provided in Figure 1. The project proposes to plant 80 shrubs. The plants will be sourced from onsite from within the proposed project area. Plants will be relocated onsite. Topsoil and mulch will also be sourced from onsite from within the proposed disturbance areas of the Project. Planting specifications for the voluntary upland restoration plan are provided as Figure 2. Proposed upland restoration measures include: 1.Removing gravel; 2.Decompacting soils, scarify and amend with topsoil or compost; 3.Adding soil amendments, as determined necessary; 4.Installing a minimum of 3 inches of bark mulch in all bare soil areas; and 5.Planting a variety of native deciduous shrub species (Table 1). Plantings will be watered by hand as needed to ensure successful establishment. Exhibit 50 Exhibit 50 Page 0737 PAGE 2 Table 1. Upland Restoration Plant Schedule Scientific Name Common Name WIS Quantity Spacing Size (Min) Notes Corylus cornuta Beaked hazelnut FACU 20 6' O.C. 24" Ht Full & bushy Oemleria cerasiformis Oso-berry FACU 30 6' O.C. 24" Ht Full & bushy Ribes sanguineum Red flowering currant FACU 30 6' O.C. 1 gal. Full & bushy Maintenance Plan and Contingency Measures A minimum of three (3) maintenance reviews will be performed within the first year following plant installation to identify any conditions that could jeopardize the successful establishment of the restoration plantings. The following list includes examples of maintenance (M) actions that may be implemented during the course of the maintenance period. This list is not intended to be exhaustive, and other actions may be implemented as deemed necessary. • Replace all dead woody plant material during Year One (M). • Remove/control weedy or exotic invasive plants in a manner consistent with current Agency guidelines and recommendations. Use of herbicides or pesticides within the restoration area would only be implemented if other measures failed or were considered unlikely to be successful. All non-native vegetation must be removed and disposed of off-site (M). • Weed all shrubs to the dripline and provide 3-inch deep mulch rings 24 inches in diameter for shrubs and 36 inches in diameter for trees (M). • Remove trash and other debris from the restoration area twice a year (M). • Selectively prune woody plants at the direction of Project Ecologist or Biologist to meet the restoration plan goal of successful establishment (e.g., thinning and removal of dead or diseased portions of trees/shrubs) (M). If, during the course of the one-year maintenance period post plant installation, there appears to be a significant problem with achieving the desired goal of successful establishment of all installed plants, the permittee shall develop a Contingency Plan in order to get the restoration area back into compliance with the desired goal. Contingency plans can include, but are not limited to, the following actions: additional plant installation, erosion control, bank stabilization, modifications to hydrology, and plant substitutions of type, size, quantity, and/or location. No coordination with the County will be completed for this voluntary restoration work as all work will be done outside of regulated critical areas. The following list includes examples of contingency (C) actions that may be implemented during the course of the monitoring period. This list is not intended to be exhaustive, and other actions may be implemented as deemed necessary. Exhibit 50 Page 0738 PAGE 3 • Replace dead plants with the same species or a substitute that meets restoration plan goals, subject to project Biologist/Ecologist and agency approval (C). • Re-plant area after reason for failure has been identified (e.g., moisture regime, poor plant stock, disease, shade/sun conditions, wildlife damage, etc.) (C). Summary Voluntary upland restoration is proposed for the County-approved access road along Oak Bay Road where this road occurs outside of the currently proposed driveway alignment. A total of 1,978 square feet will be planted with native deciduous species sourced from the proposed disturbance areas onsite. This will be a one-time planting that will be monitored to ensure plant survival past the one-year mark, consistent with nursery-purchased plant material. Attachments: Figure 1. Existing Conditions & Restoration Plan Figure 2. Restoration Planting Specifications Exhibit 50 Page 0739 Pomona WoodsVoluntary Upland Restoration PlanOak Bay Road, Jefferson County, WashingtonSOURCE: ESRI TOPOGRAPHY AND HILLSHADE EXISTING CONDITIONS & RESTORATION PLANREVISIONS DATE/DESCRIPTION (206) 309 - 8100FIGURE 1 JOB NUMBER: DESIGNED BY: DRAWN BY: CHECKED BY: DATE: #0084 JMM KAN JMM 07/18/2022 VOLUNTARY UPLAND RESTORATION PLAN SEE INSET MAP \\``\\```\\\\ ````\ `\\```` \\` \\\\ ` \` `\\ ``\\\``\`\\\\\````` ` \` UPLAND RESTORATION PLANT SCHEDULE Scientific Name Common Name WIS Quantity Spacing Size (Min) Notes Corylus cornuta Beaked hazelnut FACU 20 6' O.C. 24" Ht Full & bushy Gaultheria shallon Salal FACU 30 6' O.C. 1 gal. Full & bushy Oemleria cerasiformis Oso-berry FACU 30 6' O.C. 24" Ht Full & bushy 0 5 10 152.5 Feet SCALE: 1" = 5' Pomona Woods Proposed Project Gravel Access Road Upland Restoration ( 1,978 sf) Wetlands Off-site On-site Wetland Buffer High Impact Buffer Moderate Impact Buffer Low Impact Buffer Stream Buffer Stream LEGEND Exhibit 50 Page 0740 Pomona WoodsVoluntary Upland Restoration PlanOak Bay Road, Jefferson County, WashingtonRESTORATION SPECIFICATIONSREVISIONS DATE/DESCRIPTION (206) 309 - 8100FIGURE 2 JOB NUMBER: DESIGNED BY: DRAWN BY: CHECKED BY: DATE: #0084 JMM KAN JMM 07/18/2022 RESTORATION SPECIFICATIONS 1. GENERAL 1.1. Sequencing 1.1.1. General Construction 1.1.1.1. Contractor shall give the project biologist or ecologist a minimum of ten (10) days notice prior to beginning of construction. 1.1.1.2. No construction work shall commence until there is a meeting between the client; the project biologist or ecologist; general, clearing, and/or earthwork contractors; and the landscape contractor. The approved plans and specifications shall be reviewed to ensure that all parties involved understand the intent and the specific details related to the construction documents, specifications, and site constraints. 1.1.1.3. Locations of existing utilities have been established by field survey or obtained from available records and should be considered approximate only and not necessarily complete. It is the sole responsibility of the contractor to: (1) independently verify the accuracy of utility locations and (2) discover and avoid any utilities within the mitigation plan area(s) that are not shown, but which may be affected by implementation of the plan. Such area(s) are to be clearly marked in the field. The project biologist or ecologist shall review any conflicts with the approved grading plan prior to start of construction. 1.1.1.4. A copy of the approved plans must be on-site whenever construction is in progress, and shall remain on-site until project completion. 1.1.1.5. Construction must be performed in accordance with all agency standards, rules, codes, permit conditions, and/or other applicable ordinances and policies. 1.1.1.6. The project owner/applicant is responsible for obtaining any other related or required permits prior to the start of construction. 1.1.1.7. A qualified wetland consultant shall be on-site, as necessary, to monitor construction and approve minor revisions to the plan, to be included in as-built drawings. 1.1.1.8. During construction, the contractor must use materials and construction methods that prevent toxic substances and other pollutants from entering mitigation areas or other natural waters of the state. 1.1.1.9. Preventative measures shall be used to protect existing storm drainage systems, existing utilities, and roads. 1.1.1.10. The contractor shall provide sediment and erosion controls around the project area prior to soil disturbance from construction activity. 1.1.2. Restoration Construction: The following provides the general sequence of activities anticipated to be necessary to complete this restoration project. Some of these activities may be conducted concurrently as the project progresses. 1.1.2.1. Conduct a site meeting between the contractor; the project biologist or ecologist; and the owner’s representative to review the project plans, work areas, staging/stockpile areas, material disposal areas, and existing vegetation to be retained. 1.1.2.2. Remove gravel from upland restoration area. 1.1.2.3. Ensure a minimum of 12 inches of topsoil prior to plant installation. Topsoil to be sourced from disturbed areas onsite. 1.1.2.4. Plant shrubs and ferns as indicated on mitigation plans. Plant material to be sourced from disturbed areas onsite. 1.1.2.5. Install at least 3 inches of mulch. Mulch to be sourced from the disturbed areas onsite. 1.2. Quality Assurance 1.2.1. Plant Material: All plant materials shall be sourced from the Site and relocated from within the proposed disturbance areas and relocated into the restoration area. 1.3. Inspection, Storage and Handling 1.3.1. Protection: Plant material shall be protected during delivery to prevent desiccation and damage to the branches, trunk, root system, or earth ball. Branches shall be protected by tying-in. Exposed branches shall be covered during transport. 1.3.2. Fertilizer: Fertilizer shall be delivered in manufacturer’s standard sized bags showing weight, analysis, and manufacturer’s name. Store under a waterproof cover or in a dry place as designed by the owner’s representative. 1.3.3. Inspection: All plant materials shall be inspected upon arrival at the job site by the owner’s representative for conformity to type and quantity with regard to their respective specifications. 1.3.4. Mulch: A mulch sample shall be inspected by the project biologist or ecologist prior to the mulch being delivered to the site. 1.3.5. Storage: 1.3.5.1. Plant material not installed on the day of arrival at the site shall be stored and protected in designated areas. Plants stored on the project site shall be protected from extreme weather conditions by insulating the roots, root balls or contains with sawdust, soil, compost, bark or woodchips. Plant material shall be protected from direct exposure to wind and sun. Bare-root plant material shall be heeled-in. Cuttings and emergent plants must be protected from drying at all times and shall be heeled-in with moist soil or other insulating material. All plant material stored on-site shall be watered daily until installed. 1.3.5.2. Storage of other materials shall be in designated areas. 1.4. Scheduling 1.4.1. Planting Season: Install woody plants between October 1 and February 15 whenever the temperature is above 32 degrees F and the soil is in a workable condition, unless otherwise approved in writing. 1.4.2. Plant Installation: Except for container-grown plant material, the maximum time between the digging and installation of plant material shall be 21 days. The maximum time between plant installation and mulch placement shall be 72 hours. 1.5. Warranty 1.5.1. Plant material will not have a warranty as it will be sourced from the proposed disturbance areas onsite. If any plants die before the one-year period, they will be replaced either from relocation from onsite or purchased from a local nursery. 2. PRODUCTS AND MATERIALS 2.1. Plants 2.1.1. General: All plant material will conform to the varieties specified or shown in the plant list(s) indicated on the mitigation plants and be true to botanical name as listed in: Hitchcock, C.L., and A. Cronquist. 1973. Flora of the Pacific Northwest. University of Washington Press. 2.1.2. Shrubs: 2.1.2.1. Plant materials shall be locally grown (western Washington, western Oregon, or western BC), healthy, bushy, in vigorous growing condition, and guaranteed to be true to size, name, and variety. If replacement of plant material is necessary due to construction damage or plant failure within one year of installation, the sizes, species, and quantities shall be equal to specified plants, as indicated on the plans. 2.1.2.2. Plants shall be well-rooted, or normal growth and character, and free from disease or infestation. The project biologist or ecologist reserves the right to require replacement of substitution of any plants deemed unsuitable. 2.1.2.3. Shrubs shall have a minimum of three stems and shall be a minimum height of 18 inches. 2.1.2.4. Shrubs shall have developed root and branch systems. Do not prune branches before delivery. 2.1.2.5. Plants shall be free of splits and checks, bark abrasions, and disfiguring knots. 2.1.2.6. For deciduous plants, buds shall be intact and reasonably closed at time of planting, if dormant. 2.1.2.7. Plants shall conform to sizes indicated on the plant schedule. Plants may be larger than the minimum sizes specified. 2.1.3. Noxious Species: All plant stock and other re-vegetation materials shall be free from the seed or other plant components of any noxious or invasive species, as identified by the King County Noxious Weed Control Board. 2.1.4. Substitutions: Substitutions will not be permitted without a written request and approval from the owner’s representative, the project biologist or ecologist, and applicable agencies. 2.2. Planting Soil 2.2.1. Topsoil: If suitable stockpiled native topsoil is not available for mitigation plantings, topsoil shall be obtained from outside sources. Stockpiled or imported topsoil shall be fertile, friable, sandy loam surface soil, free of subsoil, clay lumps, brush, weeds, roots, stumps, stones larger than 1 inch in any direction, litter, or anyother extraneous or toxic matter harmful to plant growth. 2.2.2. Organic Content: Imported topsoil shall consist of organic materials amended as necessary to produce a bulk organic content of at least 10 percent and not greater than 20 percent, as determined by AASHTO-T-194. 2.2.3. Compost: Compost shall meet the definition for composted materials as defined by the Washington State Department of Ecology. 2.3. Mulch 2.3.1. Bark or woodchip mulch shall derived from Douglas fir, pine, or hemlock species. The mulch shall not contain resin, tannin, or other compounds in quantities that would be detrimental to animal, plant life, or water quality. Sawdust shall not be as mulch. 2.3.2. Mulch shall be medium-coarse ground with an approximately 3-inch minus particle size. Fine particles shall be minimized so that not more than 30 percent, by loose volume, will pass through a US No. 4 sieve. 3. EXECUTION 3.1. Soil Preparation 3.1.1. Planting Area Conditions: Contractor shall verify that plant installation conditions are suitable within the project area(s). Any unsatisfactory conditions shall be corrected prior to start of work. When conditions detrimental to plant growth are encountered, such as rubble fill, poor drainage, compacted soils, significant existing or invasive vegetation, or other obstructions, contractor shall notify the project biologist or ecologist prior to planting. The beginning of work by the contractor constitutes acceptance of conditions as satisfactory. 3.1.2. Planting in Graded Areas: In graded planting areas, plants shall be installed in newly placed topsoil. 3.1.3. Soil Decompaction/Scarification: Soils in graded/disturbed areas that are compacted and unsuitable for proper plant growth shall be decompacted and/or scarified to a minimum depth of 6 inches prior to topsoil installation. 3.2. Planting 3.2.1. Plant Layout: Proposed locations of shrubs shall be staked and identified within an approved coding system or by placement of the actual plant material. For large groupings of a single species of shrub, landscape contractor may stake the planting boundaries. 3.2.2. Obtain layout approved from the project biologist or ecologist prior to excavation of planting pits. 3.2.3. Plant Pit Dimensions: 3.2.3.1. Pit Depth: Not to exceed the root ball or container depth. 3.2.3.2. Pit Width: Measured at the ground surface, 2 times the width of the root ball or container, as indicated in typical planting details. For bare- root plants, diameter equal to the width of the root spread. 3.2.4. Setting Plants: 3.2.4.1. Shrub Planting: Shrub stock shall be planted in hand-dug holes according to planting details shown on the mitigation plans. Shrub root balls shall be set so that roots collars are 1 inch above adjacent grade. All backfill shall be gently tamped in place. 3.2.4.2. Surface Finish: Form a saucer as indicated on typical planting details, or as directed. Grade soil to form a basin on the lower side of slope plantings to catch and retain water. 3.2.4.3. Actual plant symbol quantities shown on the plants shall prevail over quantities shown on the plant schedule in the event of a discrepancy. 3.2.5. Mulching: 3.2.5.1. Non-Graded Buffer Areas: Provide a 36-inch diameter, 3-inch deep mulch ring around the base of each tree, and a 24-inch diameter, 3- inch deep mulch ring around the base of each shrub. 3.2.5.2. Water plants thoroughly after mulching. 3.2.6. Pruning: Prune immediately after planting only as directed by the project biologist or ecologist. 3.2.7. Restore Existing Natural or Landscaped Areas: 3.2.7.1. Existing natural or landscapes areas that are damaged during construction shall be restored to their original condition, unless improvements or modifications are specified for those areas. 3.2.7.2. Contractor shall exercise care to prevent injury to the trunk, roots, or branches of any trees or shrubs that are to remain. Any living woody plant that is damaged during construction shall be treated within 24 hours of occurrence, and the project biologist or ecologist shall be notified immediately of the incident. Damage treatment shall include evenly cutting broken branches, broken roots, and damaged tree bark. Injured plants shall be thoroughly watered and additional measures shall be taken, as appropriate, to aid in plant survival. 3.2.8. Final Inspection and Approval: The contractor shall notify the project biologist or ecologist in writing at least ten days prior to the requested date pf a project completion inspection. If items are to be corrected, a punch list shall be prepared by the project biologist or ecologist and submitted to the contractor for completion. After punch list items have been completed, the project biologist or ecologist shall review the project again for final acceptance of plan implementation. If punch list items require plant replacement, and the inspection occurs outside of a suitable planting season, plants shall be replaced during the next planting season. 3.2.9. As-Built Plan: Contractor is responsible for verifying plant locations and quantities on the plant schedule with those represented as symbols on the mitigation plans. Contractor shall keep a complete set of prints at the job site during construction for the purpose of recording in-the-field changes or modifications to the approved plans. This information shall be updated on a daily basis as necessary. Exhibit 50 Page 0741