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DNS Planting Plan from applicant resub 7Pichner Deck and Wall Installation Critical Area and Fabitat Management Plan LANDSERVICES NIJ 120 STATE AVE NE #190QLYMPIA, IJA 98501 zt�r;E F1171--, -- — 16 Land Services Northwest December 15, 2020 Picnner Deck and Wall Installation Critical Area and Habitat Management Plan FIGURE 6 SITE PLAN IJITH PLANTINGZONES <NOT A SURVEY) Land Services Northwest 17 December 15, 2020 Pichner Deck and Wall Installation Critical Area and Habitat Management Plan nstalled downslope from any disturbed earth and all earth disturbance will be limited to the minimum necessary to achieve the purpose. No equipment or debris will be stored in the buffer. Stormwater from the home and nearby impervious surfaces will be directed away from the area until the vegetation has established. The bare slope will be mulched with 4 inches of mulch as soon as possible to prevent erosion. The work will be done when the danger of turbid discharge to the stream is minimized in the late spring. The slopes will be watered as needed to promote vegetation growth, but not so much that it will cause erosion. All plant installations will be done by hand to minimize the potential for erosion. Mulch will be applied four inches thick in order to improve moisture retention and reduce erosion. The planting plan was conducted by hand with hand tools (shovels, trowles, rakes, ect... ) with minimal foot traffic to minimize the impact on the stabilization of the critical area. Additionally, an extra 30 kinnikinick plants were integrated into the planting plan to cover the areas of the vacated retaining walls to bolster the stability of the slope above zone 3 of the planting plan Fig 6. 8.0 MITIGATION PLAN 8.1 Impacts The project will mitigate for the unavoidable impacts to 1,452 square feet of r parian habitat through the removal of invasive species such as English ivy and Himalayan frlackberry and replanting of 3,812 square feet with a robust combination of groundcover, shrubs and trees. These plants will lead to an improvement of functions and diversity ove- the existing conditions. A net gain or positive impact is expected in landscape roughness, habitat screening, food source, nutrient uptake and aesthetics and overall habitat resilience (Figure 5). See olanting plan 8.2 Mitigation Objectives We will mitigate for the removal of vegetation and the installation of lawn, steps and walls by providing a revegetation plan that will meet the projects objectives to: a. Improve habitat as a food source and screening for wildlife b. Prevent erosion c. Discourage intrusion/degradation of the buffer d. Provide aesthetic benefits for the residents in the viewshed of the projec_ e. Stem the intrusion of invasive species a 8.3 Buffer Mitigation Functions If the buffer enhancement performs as expected, we canexpect the following lift in functions. The semi quantitative method used in the Wetland Rating System (ECY, 2014) was adapted as the resolution of performance lift is only valid to the semi quantitative Low, Medium, and High Table 1 - Buffer Functions Comparison Before and After Mitigation Land Semites Northwest 18 December 15, 2020 lluiicA rcu criteria acreenmg'-""grient Snags Other Structure uptake and Habitat Los FeaturesBefore 7Medium mitigatingmeasures LOW Meidum Low Medium Medium 7allenualin f1er mitigating High High Low Medium HighHigh measures Land Services Northwest 19 December 15, 2020 Pichrer Deck and Wall Installation Critical Area and Habitat Management Plan 8.4 Planting plan The planting plan is provided. Trees will be planted at grade in holes 1-2 =imes the width of the container or root ball. The mulch will be applied around each tree 2-4 inches deep in a two -foot diameter around the tree with an edge to retain water. Rootbound trees will be cut with sharp shears on the bottom in an x pattern to promote root growth. Four cuts will be madte vertically to allow roots to spread. Trees will be thoroughly watered in after installation. Shrl-bs will be installed in a similar manner. The species selected are typical native northwest species that usually survive our summers; however, it may be necessary to irrigate during the first two years to ensure survival. The watering will be the minimal necessary to avoid creating erosion. All retaining walls will be planted with kinnikinic to provide screening from the walls. The first 15 feet along the creek will be planted with shrubs like Red osier dogwood, Pacific ninebark and Twinberry to provide erosion protection and structure over the creek which will provide allochthonous inputs like macroinvertebrates for the fish below. The second thirty feet will be primarily trees like Sitka spruce, Western hem ock and Western red cedar and Red flowering currant to provide shade that will attenuate temperatures and eventually shade out the invasive species that have become prevalent in the area. The remaining area near the wails will be planted with groundcover (Salal and Roses) for erosion protection. Land Services (Northwest 20 December 15, 2020 Pichrer Deck and Wall Installation Critical Area and Habitat Management Plan Table 2 Tree/Shrub Species Quantity and Spacing (3,812 sq ft) on rn EHemlock Scientific Name Tsuga heterophyfla Spacing 15 ft Zone 2 Quantity 5 Cost per unit $5.04 Total $25.00 Western reef cedar Thuja plicata 15 ft 2 5 $5.00 $25.00 Sitka spruce sicea sitchensis 15 ft 2 5 $20 40 $140 00 Clustered rose Nootka rose Red flowering Rosa pisocarpa Rosa nutkana Ribes sanguineum 5 ft 5 ft loft 3 3 2 5 5 10 $5.00 $5 04 $10.00 $25.00 $25 00 $100.00 current Red osier dogrrvood Cornus alba 5 ft 20 5 $5.00 $100. 00 Pacific Nine bark Physocarpa capitatus 5 ft 10 5 $5.00 $25.00 Twinoerry Lonicera involucrata 5 ft 1 5 $5.00 $25.00 kinnikinnick Arctostaphylos uva-ursi 2 ft Walls+ 20 $4.00 $80 40 Sal al Goutheria shallon 2 ft 3 20 $2.00 $40.40 Table 3 Total Costs 8.4 Performance Standards and Monitoring The site will be monitored for five years with the as -built as Year 0. Photo points will be established in 2 points that capture the overall condition of the planting area. Monitoring will begin in the spring following the installation of the plants. Year 1 will requi-e 100 percent survival. Year 2 must have 100 percent survival of planted native plants Years 3-5 will have Land Services Northwest 19 December 15, 2020 Pichrer Deck and wall Installation Critical Area and Habitat Management Plan an 80% survival rate, if the survival rate is not met in the final year, the deficit will be replanted, and the site will be monitored for 1 more year. The survival percentage will include 10 percent of a-iy native non-invasive volunteers. Monitoring will occur each spring after the plants have sprouted leaves. Management will require prior removal of any blackberries, scotch broom or holly or other invasive plants in the planting area and replacement of any dead plants as reg4ired to meet the performance standards. A report of management actions and photos of the area will go to the City of Edmonds Development Center within a month following each site monitoring event. The invasive removal area will be monitored as well. The invasive removal area will have any non-native blackberries grubbed out. Holly will be cut down and any other invasives encountered will be removed by hand. A bond will be put in place to account for 15% of the cost of plant installation which with the added 30 kinnikinnick plants come to a total of $700.00. Making the cost of the 15% bond at $ 10 .00 9.0 CONTINGENCIES The City will be consulted on any contingency measures that are developed. The report willbe in an email by the applicant and will include pictures that illustrate the condition of the mitigation site. Contingency/maintenance activities may include, but are not limited to. 1. Replacing plants lost to vandalism, drought, or disease, as necessary; 2. Irrigating the enhancement areas only as necessary during dry weather if plants appearto be too dry, with a minimal quantity of water; 3. Remulching areas to protect from dry weather 4. Providing protection from rodents 10.0 CONCLUSIONS Development activities accidently occurred in the riparian buffer when the applicant installedhis steps, retaining walls and other landscape amenities. A geotechnical report has shown that these structures can safely remain without destabilizing the slopes and causing damage to the property. The applicant has carefully considered the best options forrevegetaling the slopes with vegetation that is appropriate for limiting erosion and adding stability to the slope. This restoration will provide benefits to the area in many different ways but most importantly, it will maintain the functions and values of the stream for the citizens of Edmond. Land Services Northwest 20 December 15, 2020